A new clinical classification of congenital biliary dilatation  HUAXI CBD classification

A new clinical classification of congenital biliary dilatation HUAXI CBD classification | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A new clinical classification of congenital biliary dilatation HUAXI CBD classification Zhenyu Xie, Siyu Pu, Shuguang Jin, Bo Xiang, Jiayin Yang, Lvnan Yan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4425208/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 19 Nov, 2024 Read the published version in BMC Pediatrics → Version 1 posted 4 You are reading this latest preprint version Abstract Objective To propose a more concise and more suitable classification of congenital biliary dilatation (CBD), and exploring the feasibility and effectiveness of this classification in diagnosis and treatment. Methods Based on the preoperative imaging data of patients with CBD admitted to the Department of Pediatric Surgery of West China Hospital of Sichuan University, from January 2015 to December 2018, a new classification of CBD was accomplished according to the site of bile duct dilatation lesions, which was named HUAXI CBD classification. The CBD was classified into 4 types: type Ⅰ (distal extra-hepatic bile duct dilatation), type Ⅱ (distal extra-hepatic combined with right and left primary hepatic bile duct dilatation), type Ⅲ (extra-hepatic combined with secondary and above hepatic bile duct dilatation), and type Ⅳ (intra-hepatic bile duct dilatation). Meanwhile, the feasibility and reliability of the HUAXI CBD classification were analyzed by analyzing the clinical treatment strategies, perioperative complications and long-term follow-up results of different subtypes. Results A total of 300 patients with CBD were included in this study. According to the HUAXI CBD classification method, 240 cases were type Ⅰ, 48 cases were type Ⅱ, 10 cases were type Ⅲ, and 2 cases were type Ⅳ. For type Ⅰ, 236 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy and 4 cases were treated non-operatively; For type Ⅱ, 48 patients underwent cholecystectomy, central hepatic duct reconstruction and Roux-en-Y hepaticojejunostomy; For type Ⅲ, 9 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy, 5 of which had intrahepatic dilatation confined to part of the liver lobe and underwent partial hepatectomy with intra-hepaticojejunostomy. One case was treated with percutaneous transhepatic cholangial drainage (PTCD) only; two type Ⅳ patients were treated with PTCD only. Patients with type Ⅰ had a normal hepatobiliary function after surgery and a good prognosis; patients with type Ⅱ had good recovery of liver function in 37 cases (77.1%), but 11 cases (22.9%) had postoperative complications during follow-up; patients with type Ⅲ and Ⅳ had high incidence of cholangitis (6/10, 2/2, respectively) and choledocholithiasis (5/10, 2/2, respectively) after surgery, especially those with diffuse intrahepatic dilatation having a poor prognosis, eventually developing cirrhosis and necessitating liver transplantation. Conclusions The HUAXI CBD classification is consistent with treatment principles, concise and easy to remember, and more suitable for CBD clinical application. congenitial biliary dilation classification imaging diagnosis prognosis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1. Introduction Congenital biliary dilatation (CBD) was formerly known as congenital choledochal cyst. This rare congenital biliary lesion manifests as one or more dilatations of the intrahepatic and/or extrahepatic bile ducts, but does not include secondary BD related to biliary obstruction caused by bile duct stones, strictures, or tumors [ 1 ]. In Western countries, the prevalence of BD is approximately 1/13,500–1/200,000 population, although the prevalence in Asia reaches 1/1,000 population and BD is approximately 3–4 times more common among females than males[ 1 – 4 ]. The incidence has increased slightly during recent years, which may be related to the development of prenatal ultrasonography, magnetic resonance cholangiopancreatography (MRCP), and other examination modalities [ 5 ]. Most cases are detected prior to puberty, and only a few cases are diagnosed in adulthood [ 3 ]. There are multiple classifications of CBD, including intrahepatic, extrahepatic, and mixed types based on the anatomical involvement; single and multiple types or limited and diffuse types based on the number of dilated bile ducts; and infantile and adult types based on the age of the patient. The most commonly used classification was proposed by Alonso-Lej et al. in 1959 and was supplemented and refined by Todani et al. in 1977[ 1 , 6 ]. Many researchers have proposed improvements or new classifications [ 7 – 9 ], but these revised classifications are still vague, complicated, and difficult to remember and apply. Moreover, these classifications are generally based on adults, and a large proportion of adult patients have secondary BD, while almost all underage patients have CBD. There are significant differences in the etiology, symptoms, and prognosis between congenital and secondary. Therefore, we aimed to propose a new classification system, CBD HUAXI classification, which is simple, easy to apply, and consistent with the principles of diagnosing and treating CBD patients. 2. Patients and Methods 2.1 Patients This retrospective study evaluated patients with CBD admitted to the Department of Pediatric Surgery (West China Hospital of Sichuan University) between January 2015 and December 2018. The inclusion criteria were age of 0–18 years, a definite diagnosis of CBD, and complete imaging data available. The exclusion criteria were communication disorders, and loss to follow-up. The study’s retrospective protocol was approved by the ethics committees of West China Hospital of Sichuan University, which waived the requirement for informed consent. 2.2 CBD HUAXI classification Patients' imaging data, perioperative information, and long-term outcomes were collected retrospectively. Preoperative preliminary classification had been performed using findings from abdominal ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and MRCP, while the final type had been determined using findings from intraoperative cholangiography. CBD was classified into 4 types based on the location of lesions in the biliary tree as revealed by the imaging data (Fig. 1 ). Type I (Fig. 2 ), only the extrahepatic bile duct dilatation, which included the common bile and common hepatic ducts, with normal or secondary intrahepatic dilatation (marked reduction or disappearance of the intrahepatic dilatation after extrahepatic choledochotomy). These lesions could be localized or diffuse, solitary or multiple, and cystic dilatation or diverticula, which correspond to Todani types I, II, III, and IVb. Type II (Fig. 3 ), the extrahepatic combined with the right or left primary hepatic ducts dilatation. Definite stenosis was present in the primary hepatic ducts (not secondary dilatation), with no significant abnormalities in the secondary and higher hepatic ducts, corresponding to the subtype of Todani type IVa. Type III (Fig. 4 ), the extrahepatic combined with secondary and higher hepatic ducts dilatation. The Intrahepatic bile duct dilatation could be confined to a single lobe or part of the liver, or could be diffusely distributed throughout the liver. Type III together with type II corresponds to Todani type IVa. Type IV (Fig. 5 ), only the intrahepatic bile duct dilatation, does not involve dilatation of the extrahepatic biliary tree which corresponds to Todani type V. 2.3 Treatment for each type of CBD HUAXI classification type I, patients underwent cholecystectomy followed by Roux-en-Y hepaticojejunostomy. This type is the most common, and although there are various forms of dilation, the surgical approach and treatment are not very difficult. type II, the extrahepatic dilatation was resected directly, and the right and left primary dilated hepatic ducts were incised and re-shaped (attention should be paid to the excision of the stenosis, in order to eliminate obstruction and drain bile adequately), followed by Roux-en-Y hepaticojejunostomy. If the lesion involved only the beginning of the primary bile duct, the prognosis was favorable with smooth postoperative drainage; however, in some cases, the stenosis segment was long and difficult to touch through the hilar, making the operation difficult, but this was rarely observed in pediatric patients. type III, the management of the extrahepatic and primary hepatic ducts dilatation was the same as type II. There was secondary or higher hepatic ducts dilatation in type III, which cannot be reached extrahepatically, so the management is tailored by the intrahepatic lesion. When the distal intrahepatic dilatation was limited to part of the hepatic segment or lobe, partial hepatectomy combined with hepaticojejunostomy should be performed (Fig. 6 ). type IV, the management of the intrahepatic hepatic duct dilatation was the same as type III, and partial hepatectomy and hepaticojejunostomy could be performed when the intrahepatic dilatation was limited. If diffuse intrahepatic bile duct dilatation was present in types III and IV, that cannot be partially resected, percutaneous transhepatic cholangial drainage (PTCD) was used to relieve the obstructive symptoms first, and liver fibrosis was closely followed up for timely liver transplantation. 2.4 Statistical analysis Continuous data were expressed as mean ± standard deviation, and categorical data were expressed as frequency (percentage). The statistical analysis was performed using SPSS software (version 22.0). 3. Results 3.1 Basic data of patients As 18 patients fulfilled the exclusion criteria, the study evaluated data from 300 patients, including 75 male and 225 female (Table 1 ). The mean age at surgery was 43 months (range: 0.5–200 months). Refer to the Todani classification system [ 1 ], there were 240 patients with type I cysts ( the common type), 58 with type IVa cysts (multiple cysts at the intra- and extrahepatic ducts), and two with type V cysts (intrahepatic bile duct cyst: single or multiple). Refer to the HUAXI classification system: 240 patients of type I (age at diagnosis ranged from 1 to 200 months), 48 patients of type II (age at diagnosis ranged from 0.5 to 154 months), ten patients of type III (age at diagnosis ranged from 17 to 94 months), two patients of type IV (age at diagnosis was 4 and 23 months). Table 1 Postoperative complications in patients with four types of biliary dilatation (n, %) Type n Short-term complication Long-term complication bile leakage pancreatic leakage traumatic bleeding severe infection cholangitis Biliary stenosis with stones complete intestinal obstruction pancreatitis pancreatic pseudocysts hepatic cirrhosis I 240 16 (6.7) 3 (1.3) 1 (0.4) 9 (3.8) 15 (6.3) 8 (3.3) 6 (2.5) 5 (2.1) 0 (0.0) 0 (0.0) II 48 4 (8.3) 2 (4.2) 1 (2.1) 3 (6.3) 6 (12.5) 4 (8.3) 0 (0.0) 2 (4.2) 1 (2.1) 0 (0.0) III 10 0 (0.0) 0 (0.0) 1 (10.0) 3 (30.0) 6 (60.0) 5 (50.0) 0 (0.0) 0 (0.0) 0 (0.0) 5 (55.0) IV 2 0 (0.0) 0 (0.0) 0 (0.0) 1 (50.0) 2 (100.0) 2 (100.0) 0 (0.0) 0 (0.0) 0 (0.0) 2 (100.0) Total 300 20(6.7) 5(1.7) 3 (1.0) 16 (5.3) 29 (9.7) 19 (6.3) 6 (2.0) 7 (2.3) 1 (0.3) 7 (2.3) 3.2 Treatment and follow-up of each type Among the 240 patients in our type I group, 236 were treated surgically and 195 (82.6%) had favorable postoperative after surgery. 41 patients (17.4%) had postoperative complications, yet all maintained a basically normal liver function after treatment. The other four patients were requested conservative treatment due to insignificant bile duct dilatation and normal liver function. At present, all four of these non-operated patients have no further deterioration of liver function. All 48 patients in our type II group were treated surgically, and 14 patients (29.2%) developed postoperative complications. Nine of these patients improved after symptomatic conservative treatment, and the liver function was basically normal at now. Another four patients with bile duct stenosis with cholelithiasis were reoperated, to remove the stricture and stones, and liver function was stable at follow-up. The last one with pancreatic pseudocyst is under continuous observation. Nine patients with type III were treated surgically (five had partial hepatectomy with hepaticojejunostomy because the dilatation was limited to one liver lobe (LL), and four had only extrahepatic dilatation resected for diffuse intrahepatic lesions), while the other patient could not tolerate surgery as well as diffuse lesions, only PTCD was performed. Seven patients had postoperative complications, of which 2 were able to maintain stable liver function after treatment, the other 5 had liver transplantation. Both patients in our type IV group had diffuse intrahepatic bile duct dilatation that could not be locally resected, so PTCD was performed first to relieve the obstructive symptoms. However, both patients subsequently underwent liver transplantation after experiencing liver failure. Five type III and two type IV patients with diffuse intrahepatic dilatation developed recurrent severe cholangitis, significant liver fibrosis and hypohepatia during follow-up, and all eventually underwent liver transplantation. 3.3 Follow-up Complete follow-up data were available for all 300 patients (mean follow-up: 43.7 months, range: 0–68 months), of which 229 (76.3%) patients were free from long-term complications, and had relatively normal hepatobiliary function; 31 (10.3%) patients developed early complications and 46 patients (15.3%) developed long-term complications, as shown in Table 1 . Early postoperative complications included bile leakage, pancreatic leakage, bleeding, and infection. Bile leakage occurred in 20 patients (6.7%), and improved after treatment via re-anastomosis (five patients) or continuous abdominal drainage (15 patients). Pancreatic leakage occurred in five patients (1.7%), and improved after treatment via ultrasound-guided pancreatic head puncture and drainage in two patient and continuous abdominal drainage in the others. Traumatic bleeding occurred in three patients (1.0%), and improved after treatment via re-operation in two patients and conservative treatment in the other. Sixteen cases (5.3%) had severe postoperative infections, including incisional infections (five cases, 1.7%), abdominal infections (six cases, 2.0%) and bloodstream infections (five cases, 1.7%), which were cured with anti-infective treatment. Biliary stenosis with stones occurred in 19 patients (6.3%), of which two patients of type II were resolved after endoscopic retrograde cholangiopancreatography followed by papillosphincterotomy or choledochoscopy for stone extraction; another two type II and eight type I patients were reoperated to remove the stone and reshape the anastomosis; Five type III and two type IV patients with diffuse intrahepatic dilatation had severe cirrhosis, and were treated or awaiting liver transplantation. Complete intestinal obstruction was relieved by enterolysis in 6 cases (2.0%). Seven cases (2.3%) with pancreatitis were treated conservatively and improved. One case (0.3%) of pancreatic pseudocyst was treated with internal drainage of the cystic jejunostomy. 4. Discussion 4.1 Current CBD classification Vater et al. first described BD in 1723, which was divided into 3 types by Alonso-Lej et al. in 1959, and Todani et al. added types IV and V to their classification system in 1976 [ 1 , 6 ], which is still widely used in clinical practice. The Todani classification system was based on the anatomical knowledge and surgical procedures of that time, as well as the concept that biliary cystic dilatation could occur in the common bile ducts as well as any part of the intrahepatic and extrahepatic bile ducts [ 1 ]. The Todani system was effective for guiding the surgical treatment strategies of that time, however, the small sample size and relatively early examinations and surgical techniques led to a system that is now considered confusing and misleading. First, dilatation of the intrahepatic bile duct is often secondary to dilatation of the extrahepatic duct, which can obscure the distinction between types I and IV [ 8 ]. Second, types I and IVa account for > 95% of cases, and the relative rarity of the other types makes the Todani classification impractical[ 10 ]. Third, each type can have different etiologies, postoperative complications, risks of malignancy, and long-term outcomes. For example, Caroli disease has a clear genetic background and is usually combined with liver fibrosis and extrahepatobiliary lesions[ 11 – 13 ]. Therefore, several individuals and institutions have questioned the continued clinical use of the Todani classification system and have proposed new ways of classifying the disease. Subsequently, Todani provided an update that included the concept of pancreaticobiliary maljunction and indicated that types Ia, Ic, and IVa are usually associated with pancreaticobiliary maljunction [ 14 ], however, this update is no practical guide to the operation. Lenriot et al. argued that the Todani classification emphasizes the association of extrahepatic and intrahepatic bile duct dilatation without considering their distinct nature, especially regarding the treatment and long-term prognosis of intrahepatic bile duct dilatation [ 9 ]. Therefore, in 1998, they suggested combining Todani type IVb with multiple extrahepatic dilatations into type Id, and regrouping Todani type IVa with multiple extrahepatic and intrahepatic dilatations into a type IV based on the morphology of intrahepatic bile duct dilatation (cystic, segmental, or fusiform dilatations). This modification differentiates extrahepatic bile duct dilatation in cases associated with intrahepatic duct dilatation and improves their classification. Visser et al. have suggested that the Todani classification system actually encompasses four different diseases in terms of their pathogenesis, risk of malignancy, natural history, and treatment, and thus proposed describing these entities as congenital choledochal cyst, choledochocele, choledochal diverticulum, and Caroli's disease [ 8 ]. Many researchers have subsequently supported this approach [ 15 ]. However, these four diseases have similar clinical features and generally similar treatments (with the exception of Caroli's disease), so they can be differentiated but not necessarily be completely independent, which seems to over-exaggerate the differences of each type [ 7 , 8 ]. Dong et al. also concluded that the Todani classification was cumbersome, did not consider pathological results, and was confusing regarding the classification of extrahepatic bile duct dilatation, which led them to propose a new system based on anatomical and clinicopathological features from analysis of plenty of data and clinical practices [ 7 ]. Their system combines cases that only involve the extrahepatic bile ducts, subdivides Todani type IVa, and classifies intrahepatic dilatation as involving the peripheral or central hepatic ducts, with further classification according to the extent of liver involvement. Thus, the Biliary Surgery Group of the Chinese Society of Medical Surgery acknowledged in 2017 that this classification system was useful for guiding the surgical strategy. However, Dong's exhaustive classification system is complicated to remember and apply, which is a challenge in primary hospitals, and this system includes some overlap in terms of treatment strategy, with unclear boundaries. Moreover, Dong's classification system does not cover cases with extrahepatic dilatation plus intrahepatic distal dilatation 4.2 HUAXI CBD classification Although each of these classifications has its own rationale and innovations, and has more or less improved the CBD classification, problems remain. Firstly, these classifications are not comprehensive, especially given that underage CBD patients account for 75% of all BD cases, but almost all of these classifications are based on adult patients, of which secondary BD accounts for a large proportion, and the morbidity, imaging features, risk of malignancy and prognosis of secondary BD are significantly different compared to CBD [ 8 , 16 – 18 ]. In addition, with the development of imaging methods, currently commonly used imaging techniques such as abdominal ultrasonography, CT, MRI, MRCP, intraoperative cholangiography, and cholangioscopy have greatly assisted clinical diagnosis and treatment, and demand a more modern classification. Among these options, although MRCP is susceptible to interference and has a high false positive rate in cases with bile duct stones, it is considered the best modality for diagnosing and evaluating CBD at present, due to its noninvasive, highly sensitive and specific, allows clear visualization of hepato-pancreato-biliary structures, which can guide the procedure and reduce the number of invasive operations[ 19 – 22 ]. Cholangiography is highly sensitive and can directly identify dilatation inside and outside the liver, which aid in classification and can help identify intrahepatic bile duct stenosis to guide surgery. Intraoperative cholangioscopy can assist in determining secondary or primary intrahepatic BD, and directly visualizing and measuring the caliber of its stenotic segment with a microscope [ 22 ]. It can also be supplemented with endoscopic ultrasound to detect the intrahepatic ducts more clearly, with sensitivity and specificity up to 90% and 93%, and in cases of combined stone formation, lithotripsy, stone extraction and flushing can be performed simultaneously (Fig. 7 ) [ 23 – 25 ]. Based on the shortcomings of the above classification and the advantages of the current imaging techniques, as well as the clinical experience of our team in treating minor CBD cases, we proposed the HUAXI CBD classification. Inspired by the concept of "central hepatic duct" in Dong's classification, CBD is divided into four types, each with distinctive treatment characteristics. The basic principles for treating BD involve resection of the dilated bile duct(s), relief of secondary symptoms, and restoration of bile flow [ 7 ]. Thus, in this research, patients with HUAXI type I, II and III CBD underwent complete resection of the dilated extrahepatic bile duct and a high Roux-en-Y hepaticojejunostomy, with the anastomosis made as large as possible to reduce the incidence of postoperative stenosis. Types II, III, and IV, because they involve hilar or intrahepatic bile duct dilatation, should be resected or shaped for stenoses that can be explored in the portal region, while for intrahepatic intrahepatic stenosis, close long-term postoperative follow-up is needed to pay attention to cholelithiasis and possible development of cholangiocarcinoma [ 26 ]. Type III and IV intrahepatic dilatation may be confined to a single LL, but more often the dilatations are widely distributed throughout the liver. For children with lesions mainly confined to a single lobe, complicated by recurrent intrahepatic stones and cholangitis, lobectomy can be considered. In cases where the lesion involves the whole liver, especially in Caroli's disease, which is often associated with genetic abnormalities and rapid progression of liver fibrosis, there is no curative surgical option and liver transplantation is usually considered. Overall, our experience showed that for HUAXI type I CBD, where the lesion involves only the extrahepatic ducts, the surgery is not difficult, with few complications and favorable recovery of liver function, especially in recent years with the popular use of laparoscopic and robot-assisted technology, the surgery is less traumatic and faster recovery. In HUAXI CBD type II, there is definite stenosis at the porta hepatis, requiring hilar cholangioplasty, which may be caused by the independent development of the intrahepatic and extrahepatic bile ducts during the embryonic period [ 27 ]. Nevertheless, most immature patients with type II experience have symptomatic relief and better prognosis than those in adults, after complete resection of the hilar stenosis. In type III and IV cases with limited resectable intrahepatic lesions, a better prognosis can be obtained. However, Caroli's disease is often associated with genetic disorder and can progress rapidly to hepatic fibrosis, and in about 50% of cases is combined with renal cystic lesions or medullary spongy kidneys. In these cases, hepaticojejunostomy or puncture and drainage of the intrahepatic lesion can only delay disease progression, which is inevitably followed by liver failure, and the only effective option is liver transplantation [ 28 , 29 ]. The rate of post-treatment complications varied among patients with different types of HUAXI CBD classification. The most common early complication was bile leak (6.7%), mainly seen in type I and type II patients, which may be related to the early lack of experience in laparoscopic surgery, resulting in poor suturing and excessive anastomotic tension, but gradually decreased with the accumulation of surgical techniques and experience. Cholangitis was the most common long-term complication (9.7%), with 6/10 and 2/2 in type III and IV cases, respectively. Biliary stenosis with stones Biliary stenosis with stones was also a highly prevalent long-term complication (6.3%), and can occured in all types of patients, with a higher incidence in types III and IV cases. Stones are often removed by surgical incision or choledochoscopy. Literature has also reported good results in pediatric patients using small-sized ureteroscopes to remove the stones [ 30 ]. The occurrence of cholelithiasis and cholangitis is considered closely related to intrahepatic bile duct stenosis, and alternating stenosis and dilatation are morphological features underlying the occurrence of cholangitis and cholelithiasis, which is consistent with our clinical experience [ 31 ]. However, the feature of single-center retrospective study and small number of type III and IV cases may have biased the data and affected the authenticity of the results. We are currently conducting a multicenter collaboration with three hospitals to conduct prospective trials to test the use of this classification. In summary, the CBD classification current commonly used in clinical practice is not suitable to CBD patients who are mainly minors, and suffers from the problems of complicated classification, unfavorable to memory and clinical application. Therefore, our team proposed the HUAXI CBD classification based on preoperative imaging features and treatment strategies. The classification is consistent with the treatment principles of CBD, with clear and concise demarcation of each type, and easy to remember. Moreover, the type of each patient can be determined by preoperative imaging data, which helps to guide the operation. The classification can then be further determined by intraoperative imaging data, which helps in subsequent treatment. In conclusion, HUAXI CBD classification is more suitable for the clinical application of CBD patients. Abbreviations CBD Congenital biliary dilatation MRCP Magnetic resonance cholangiopancreatography CT Computed tomography MRI magnetic resonance imaging PTCD percutaneous transhepatic cholangial drainage LL Liver lobe Declarations Ethics approval and consent to participate This study was approved by the ethics committee of West China hospital of Sichuan university (approval no.202411). We certify that the study was performed in accordance with the 1964 declaration of HELSINKI and later amendments. Consent for publication Written informed consent was obtained from the patient for publication of this study and any accompanying images. Competing interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Funding This work was supported by the National Natural Science Foundation of China (81571473). Author Contribution First author: Zhenyu Xie, drafting the work and substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work.Co-first author: Siyu Pu, drafting the work and substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work.Corresponding author: Shuguang Jin, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved, and Final approval of the version to be published.Author: Bo Xiang, reviewing the work critically for important intellectual content.Author: Jiayin Yang, reviewing the work critically for important intellectual content.Author: Lvnan Yan, reviewing the work critically for important intellectual content. 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Contemporary ‘Urologic’ intervention in the pancreaticobiliary tree. Urology. 2001;57:21–5. Todani T, Narusue M, Watanabe Y, Tabuchi K, Okajima K. Management of Congenital Choledochal Cyst with Intrahepatic Involvement. Ann Surg. 1978;187:272–80. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 19 Nov, 2024 Read the published version in BMC Pediatrics → Version 1 posted Editorial decision: Revision requested 19 Jun, 2024 Editor assigned by journal 19 Jun, 2024 Submission checks completed at journal 19 Jun, 2024 First submitted to journal 15 May, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4425208","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":316348339,"identity":"399b5d6d-e864-486f-936e-c9662b127847","order_by":0,"name":"Zhenyu Xie","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Zhenyu","middleName":"","lastName":"Xie","suffix":""},{"id":316348341,"identity":"9e61fb82-723d-47b6-8541-eb9af4f8ebc9","order_by":1,"name":"Siyu Pu","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Siyu","middleName":"","lastName":"Pu","suffix":""},{"id":316348342,"identity":"d2d5e9b2-44d8-429b-aa2c-1bb0525db638","order_by":2,"name":"Shuguang Jin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6UlEQVRIiWNgGAWjYDACCQYGgwQGGx42/uYDDA8MiNeSJscvcSyBIYFYLUBw2FiyIceAIYEYHfKz2y8UPNzBnLjhwJmPHxIKDiduZ2B++OgGHi0Gd84UGCSeYUvccLh3s0SCweHEnQ1sxsY5+LRI5CQYJLbxAG05uwGsZcMBHjZpfFrkZ4C1SABV5jz+QZQWhhvpB4BaDEDeZyPOFoMbOQxALQmgQDazSDBIN95wmIBf5GekPzP82fYfFJWPb3z4Yy274Xjzw8d4HcbAY4Ycf80MDMx4lYMA++MHSLw6gupHwSgYBaNg5AEAiI1WWEUUTkwAAAAASUVORK5CYII=","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":true,"prefix":"","firstName":"Shuguang","middleName":"","lastName":"Jin","suffix":""},{"id":316348343,"identity":"b97946bb-5bc3-4a37-bb35-18be4deb2034","order_by":3,"name":"Bo Xiang","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Bo","middleName":"","lastName":"Xiang","suffix":""},{"id":316348344,"identity":"a4c76b19-2cb0-488b-8919-580c9ea1ca06","order_by":4,"name":"Jiayin Yang","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Jiayin","middleName":"","lastName":"Yang","suffix":""},{"id":316348346,"identity":"cf74aac9-aad3-4877-9da8-7e55b8c1d2c4","order_by":5,"name":"Lvnan Yan","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Lvnan","middleName":"","lastName":"Yan","suffix":""}],"badges":[],"createdAt":"2024-05-15 12:40:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4425208/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4425208/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12887-024-05220-0","type":"published","date":"2024-11-19T15:57:36+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":60595080,"identity":"357ec67d-1929-423e-a0b7-b6f24c2a0c5c","added_by":"auto","created_at":"2024-07-18 15:26:42","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2431320,"visible":true,"origin":"","legend":"\u003cp\u003eHUAXI CBD classification system: Type I dilatation involved only extrahepatic bile duct dilatation; type II dilatation involved extrahepatic and the right or left primary hepatic bile dilatation; type III dilatation involved extrahepatic combined with secondary and higher hepatic ducts dilatation; type IV dilatation involved only intrahepatic bile duct dilatation.\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/b01c64a8a46be55333f1c105.png"},{"id":60595769,"identity":"2c780952-5d6c-4ec5-ab06-99f0e098da7c","added_by":"auto","created_at":"2024-07-18 15:34:42","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":2104327,"visible":true,"origin":"","legend":"\u003cp\u003eImaging features of HUAXI CBD type I\u003cstrong\u003e.\u003c/strong\u003e MRCP revealed pure cystic-like \u003cstrong\u003e(2a) \u003c/strong\u003eand shuttle-like \u003cstrong\u003e(2b)\u003c/strong\u003e dilatation of extrahepatic bile ducts; intraoperative cholangiography revealed pure cystic-like dilatation of extrahepatic bile ducts \u003cstrong\u003e2(c)\u003c/strong\u003e; after incision, the left hepatic duct was found to be narrow at the beginning and the right hepatic duct was normal \u003cstrong\u003e2(d)\u003c/strong\u003e. The white arrows point to dilatations and the red arrows point to strictures.\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/b9015acb5392be8188d3640f.png"},{"id":60595768,"identity":"73829711-215a-43a5-96d3-12047e0041c2","added_by":"auto","created_at":"2024-07-18 15:34:42","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":855248,"visible":true,"origin":"","legend":"\u003cp\u003eImaging features of HUAXI CBD type II. MRI revealed extrahepatic bile ducts with right hepatic duct dilation\u003cstrong\u003e(3a)\u003c/strong\u003e or with left hepatic duct dilatation \u003cstrong\u003e(3b)\u003c/strong\u003e, and MRCP\u003cstrong\u003e (3c)\u003c/strong\u003eand intraoperative cholangiography\u003cstrong\u003e (3d)\u003c/strong\u003e revealed extrahepatic combine with right and left hepatic duct dilatation. The white arrows point to dilatations and the red arrows point to strictures.\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/b15f2fbca6011cb163f1de81.png"},{"id":60595078,"identity":"614c52d3-84a6-4f3f-8fb9-d3ed6991864f","added_by":"auto","created_at":"2024-07-18 15:26:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":761646,"visible":true,"origin":"","legend":"\u003cp\u003eImaging features of HUAXI CBD type III. Enhanced CT \u003cstrong\u003e(4a)\u003c/strong\u003e, MRI \u003cstrong\u003e(4b)\u003c/strong\u003e, MRCP \u003cstrong\u003e(4c) \u003c/strong\u003eand intraoperative cholangiography \u003cstrong\u003e(4d)\u003c/strong\u003e revealed extrahepatic bile ducts and left high grade hepatic duct dilatation. The white arrows point to dilatations and the red arrows point to strictures.\u003c/p\u003e","description":"","filename":"Fig4.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/df6362b36e5671c6f707c477.png"},{"id":60595082,"identity":"3a171342-2a05-451a-b0f9-31364323c3f6","added_by":"auto","created_at":"2024-07-18 15:26:43","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":918596,"visible":true,"origin":"","legend":"\u003cp\u003eImaging features of HUAXI CBD type IV \u003cstrong\u003e5(A).\u003c/strong\u003e A patient's MRI coronal \u003cstrong\u003e(5a)\u003c/strong\u003eand cross-sectional \u003cstrong\u003e(5b)\u003c/strong\u003e views of the right intrahepatic bile duct with multiple dilatations; MRCP\u003cstrong\u003e (5c)\u003c/strong\u003e and intraoperative cholangiogram \u003cstrong\u003e(5d)\u003c/strong\u003eof the other patient revealed only significant dilatation of the left intrahepatic duct. The white arrows point to the dilatations and the red arrows point to stomach.\u003c/p\u003e","description":"","filename":"Fig5.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/0e15ddd5653d001ce2d0734e.png"},{"id":60595077,"identity":"39ca8f92-83b3-4716-9639-9f9bd343c7a2","added_by":"auto","created_at":"2024-07-18 15:26:42","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":15034805,"visible":true,"origin":"","legend":"\u003cp\u003eTwo patient with HUAXI CBD type III underwent left hepaticojejunostomy when the left hepatic duct was found to be significantly dilated during the left hemihepatectomy (the white arrow points to the Roux-en-Y hepaticojejunostomy and the black arrow points to the common hepatic duct and jejunal anastomosis).\u003c/p\u003e","description":"","filename":"Fig6.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/e775296ab78426112158263d.png"},{"id":60595767,"identity":"fcb30b48-7754-49d8-b8af-7d910fc65898","added_by":"auto","created_at":"2024-07-18 15:34:42","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":3097122,"visible":true,"origin":"","legend":"\u003cp\u003eLeft: a stone is seen after the choledochoscope passed through the stenotic segment. Right: intracholedochal stricture was seen with the choledochoscope (the white arrow points to the stone and the red arrow points to the biliary stricture).\u003c/p\u003e","description":"","filename":"Fig7.png","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/45231e8e2878d7c1d1bdbd1e.png"},{"id":69834913,"identity":"5fd43961-fc1c-4a7d-a203-b29affb9f5b7","added_by":"auto","created_at":"2024-11-25 16:10:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":48081391,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4425208/v1/6f77fdd7-2279-48ee-92f7-d5d1f6ec1719.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A new clinical classification of congenital biliary dilatation HUAXI CBD classification","fulltext":[{"header":"1. Introduction","content":" \u003cp\u003eCongenital biliary dilatation (CBD) was formerly known as congenital choledochal cyst. This rare congenital biliary lesion manifests as one or more dilatations of the intrahepatic and/or extrahepatic bile ducts, but does not include secondary BD related to biliary obstruction caused by bile duct stones, strictures, or tumors [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. In Western countries, the prevalence of BD is approximately 1/13,500\u0026ndash;1/200,000 population, although the prevalence in Asia reaches 1/1,000 population and BD is approximately 3\u0026ndash;4 times more common among females than males[\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The incidence has increased slightly during recent years, which may be related to the development of prenatal ultrasonography, magnetic resonance cholangiopancreatography (MRCP), and other examination modalities [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Most cases are detected prior to puberty, and only a few cases are diagnosed in adulthood [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThere are multiple classifications of CBD, including intrahepatic, extrahepatic, and mixed types based on the anatomical involvement; single and multiple types or limited and diffuse types based on the number of dilated bile ducts; and infantile and adult types based on the age of the patient. The most commonly used classification was proposed by Alonso-Lej et al. in 1959 and was supplemented and refined by Todani et al. in 1977[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Many researchers have proposed improvements or new classifications [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], but these revised classifications are still vague, complicated, and difficult to remember and apply. Moreover, these classifications are generally based on adults, and a large proportion of adult patients have secondary BD, while almost all underage patients have CBD. There are significant differences in the etiology, symptoms, and prognosis between congenital and secondary. Therefore, we aimed to propose a new classification system, CBD HUAXI classification, which is simple, easy to apply, and consistent with the principles of diagnosing and treating CBD patients.\u003c/p\u003e"},{"header":"2. Patients and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Patients\u003c/h2\u003e \u003cp\u003eThis retrospective study evaluated patients with CBD admitted to the Department of Pediatric Surgery (West China Hospital of Sichuan University) between January 2015 and December 2018. The inclusion criteria were age of 0\u0026ndash;18 years, a definite diagnosis of CBD, and complete imaging data available. The exclusion criteria were communication disorders, and loss to follow-up. The study\u0026rsquo;s retrospective protocol was approved by the ethics committees of West China Hospital of Sichuan University, which waived the requirement for informed consent.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 CBD HUAXI classification\u003c/h2\u003e \u003cp\u003ePatients' imaging data, perioperative information, and long-term outcomes were collected retrospectively. Preoperative preliminary classification had been performed using findings from abdominal ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and MRCP, while the final type had been determined using findings from intraoperative cholangiography. CBD was classified into 4 types based on the location of lesions in the biliary tree as revealed by the imaging data (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eType I (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), only the extrahepatic bile duct dilatation, which included the common bile and common hepatic ducts, with normal or secondary intrahepatic dilatation (marked reduction or disappearance of the intrahepatic dilatation after extrahepatic choledochotomy). These lesions could be localized or diffuse, solitary or multiple, and cystic dilatation or diverticula, which correspond to Todani types I, II, III, and IVb.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eType II (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), the extrahepatic combined with the right or left primary hepatic ducts dilatation. Definite stenosis was present in the primary hepatic ducts (not secondary dilatation), with no significant abnormalities in the secondary and higher hepatic ducts, corresponding to the subtype of Todani type IVa.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eType III (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), the extrahepatic combined with secondary and higher hepatic ducts dilatation. The Intrahepatic bile duct dilatation could be confined to a single lobe or part of the liver, or could be diffusely distributed throughout the liver. Type III together with type II corresponds to Todani type IVa.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eType IV (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), only the intrahepatic bile duct dilatation, does not involve dilatation of the extrahepatic biliary tree which corresponds to Todani type V.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Treatment for each type of CBD HUAXI classification\u003c/h2\u003e \u003cp\u003etype I, patients underwent cholecystectomy followed by Roux-en-Y hepaticojejunostomy. This type is the most common, and although there are various forms of dilation, the surgical approach and treatment are not very difficult.\u003c/p\u003e \u003cp\u003etype II, the extrahepatic dilatation was resected directly, and the right and left primary dilated hepatic ducts were incised and re-shaped (attention should be paid to the excision of the stenosis, in order to eliminate obstruction and drain bile adequately), followed by Roux-en-Y hepaticojejunostomy. If the lesion involved only the beginning of the primary bile duct, the prognosis was favorable with smooth postoperative drainage; however, in some cases, the stenosis segment was long and difficult to touch through the hilar, making the operation difficult, but this was rarely observed in pediatric patients.\u003c/p\u003e \u003cp\u003etype III, the management of the extrahepatic and primary hepatic ducts dilatation was the same as type II. There was secondary or higher hepatic ducts dilatation in type III, which cannot be reached extrahepatically, so the management is tailored by the intrahepatic lesion. When the distal intrahepatic dilatation was limited to part of the hepatic segment or lobe, partial hepatectomy combined with hepaticojejunostomy should be performed (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003etype IV, the management of the intrahepatic hepatic duct dilatation was the same as type III, and partial hepatectomy and hepaticojejunostomy could be performed when the intrahepatic dilatation was limited.\u003c/p\u003e \u003cp\u003eIf diffuse intrahepatic bile duct dilatation was present in types III and IV, that cannot be partially resected, percutaneous transhepatic cholangial drainage (PTCD) was used to relieve the obstructive symptoms first, and liver fibrosis was closely followed up for timely liver transplantation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.4 Statistical analysis\u003c/em\u003e\u003c/h2\u003e \u003cp\u003eContinuous data were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and categorical data were expressed as frequency (percentage). The statistical analysis was performed using SPSS software (version 22.0).\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Basic data of patients\u003c/h2\u003e \u003cp\u003eAs 18 patients fulfilled the exclusion criteria, the study evaluated data from 300 patients, including 75 male and 225 female (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The mean age at surgery was 43 months (range: 0.5\u0026ndash;200 months). Refer to the Todani classification system [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], there were 240 patients with type I cysts ( the common type), 58 with type IVa cysts (multiple cysts at the intra- and extrahepatic ducts), and two with type V cysts (intrahepatic bile duct cyst: single or multiple). Refer to the HUAXI classification system: 240 patients of type I (age at diagnosis ranged from 1 to 200 months), 48 patients of type II (age at diagnosis ranged from 0.5 to 154 months), ten patients of type III (age at diagnosis ranged from 17 to 94 months), two patients of type IV (age at diagnosis was 4 and 23 months).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cb\u003ePostoperative complications in patients with four types of biliary dilatation (n, %)\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"13\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eType\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003en\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c6\" namest=\"c3\"\u003e \u003cp\u003eShort-term complication\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c13\" namest=\"c7\"\u003e \u003cp\u003eLong-term complication\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ebile leakage\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003epancreatic leakage\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003etraumatic bleeding\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003esevere infection\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003echolangitis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eBiliary stenosis with stones\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003ecomplete intestinal obstruction\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003epancreatitis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003epancreatic pseudocysts\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c13\"\u003e \u003cp\u003ehepatic cirrhosis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e240\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16 (6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3 (1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1 (0.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e9 (3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e15 (6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e8 (3.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e6 (2.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e5 (2.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2 (4.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1 (2.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3 (6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e6 (12.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e4 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e2 (4.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e1 (2.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1 (10.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3 (30.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e6 (60.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e5 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e5 (55.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e2 (100.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e2 (100.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e2 (100.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e20(6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5(1.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3 (1.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e16 (5.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e29 (9.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e19 (6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e6 (2.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e7 (2.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e1 (0.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e7 (2.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Treatment and follow-up of each type\u003c/h2\u003e \u003cp\u003eAmong the 240 patients in our type I group, 236 were treated surgically and 195 (82.6%) had favorable postoperative after surgery. 41 patients (17.4%) had postoperative complications, yet all maintained a basically normal liver function after treatment. The other four patients were requested conservative treatment due to insignificant bile duct dilatation and normal liver function. At present, all four of these non-operated patients have no further deterioration of liver function.\u003c/p\u003e \u003cp\u003eAll 48 patients in our type II group were treated surgically, and 14 patients (29.2%) developed postoperative complications. Nine of these patients improved after symptomatic conservative treatment, and the liver function was basically normal at now. Another four patients with bile duct stenosis with cholelithiasis were reoperated, to remove the stricture and stones, and liver function was stable at follow-up. The last one with pancreatic pseudocyst is under continuous observation.\u003c/p\u003e \u003cp\u003eNine patients with type III were treated surgically (five had partial hepatectomy with hepaticojejunostomy because the dilatation was limited to one liver lobe (LL), and four had only extrahepatic dilatation resected for diffuse intrahepatic lesions), while the other patient could not tolerate surgery as well as diffuse lesions, only PTCD was performed. Seven patients had postoperative complications, of which 2 were able to maintain stable liver function after treatment, the other 5 had liver transplantation.\u003c/p\u003e \u003cp\u003eBoth patients in our type IV group had diffuse intrahepatic bile duct dilatation that could not be locally resected, so PTCD was performed first to relieve the obstructive symptoms. However, both patients subsequently underwent liver transplantation after experiencing liver failure.\u003c/p\u003e \u003cp\u003eFive type III and two type IV patients with diffuse intrahepatic dilatation developed recurrent severe cholangitis, significant liver fibrosis and hypohepatia during follow-up, and all eventually underwent liver transplantation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Follow-up\u003c/h2\u003e \u003cp\u003eComplete follow-up data were available for all 300 patients (mean follow-up: 43.7 months, range: 0\u0026ndash;68 months), of which 229 (76.3%) patients were free from long-term complications, and had relatively normal hepatobiliary function; 31 (10.3%) patients developed early complications and 46 patients (15.3%) developed long-term complications, as shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eEarly postoperative complications included bile leakage, pancreatic leakage, bleeding, and infection. Bile leakage occurred in 20 patients (6.7%), and improved after treatment via re-anastomosis (five patients) or continuous abdominal drainage (15 patients). Pancreatic leakage occurred in five patients (1.7%), and improved after treatment via ultrasound-guided pancreatic head puncture and drainage in two patient and continuous abdominal drainage in the others. Traumatic bleeding occurred in three patients (1.0%), and improved after treatment via re-operation in two patients and conservative treatment in the other. Sixteen cases (5.3%) had severe postoperative infections, including incisional infections (five cases, 1.7%), abdominal infections (six cases, 2.0%) and bloodstream infections (five cases, 1.7%), which were cured with anti-infective treatment.\u003c/p\u003e \u003cp\u003eBiliary stenosis with stones occurred in 19 patients (6.3%), of which two patients of type II were resolved after endoscopic retrograde cholangiopancreatography followed by papillosphincterotomy or choledochoscopy for stone extraction; another two type II and eight type I patients were reoperated to remove the stone and reshape the anastomosis; Five type III and two type IV patients with diffuse intrahepatic dilatation had severe cirrhosis, and were treated or awaiting liver transplantation. Complete intestinal obstruction was relieved by enterolysis in 6 cases (2.0%). Seven cases (2.3%) with pancreatitis were treated conservatively and improved. One case (0.3%) of pancreatic pseudocyst was treated with internal drainage of the cystic jejunostomy.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e4.1 Current CBD classification\u003c/h2\u003e \u003cp\u003eVater et al. first described BD in 1723, which was divided into 3 types by Alonso-Lej et al. in 1959, and Todani et al. added types IV and V to their classification system in 1976 [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], which is still widely used in clinical practice. The Todani classification system was based on the anatomical knowledge and surgical procedures of that time, as well as the concept that biliary cystic dilatation could occur in the common bile ducts as well as any part of the intrahepatic and extrahepatic bile ducts [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The Todani system was effective for guiding the surgical treatment strategies of that time, however, the small sample size and relatively early examinations and surgical techniques led to a system that is now considered confusing and misleading. First, dilatation of the intrahepatic bile duct is often secondary to dilatation of the extrahepatic duct, which can obscure the distinction between types I and IV [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Second, types I and IVa account for \u0026gt;\u0026thinsp;95% of cases, and the relative rarity of the other types makes the Todani classification impractical[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Third, each type can have different etiologies, postoperative complications, risks of malignancy, and long-term outcomes. For example, Caroli disease has a clear genetic background and is usually combined with liver fibrosis and extrahepatobiliary lesions[\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Therefore, several individuals and institutions have questioned the continued clinical use of the Todani classification system and have proposed new ways of classifying the disease. Subsequently, Todani provided an update that included the concept of pancreaticobiliary maljunction and indicated that types Ia, Ic, and IVa are usually associated with pancreaticobiliary maljunction [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], however, this update is no practical guide to the operation.\u003c/p\u003e \u003cp\u003eLenriot et al. argued that the Todani classification emphasizes the association of extrahepatic and intrahepatic bile duct dilatation without considering their distinct nature, especially regarding the treatment and long-term prognosis of intrahepatic bile duct dilatation [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Therefore, in 1998, they suggested combining Todani type IVb with multiple extrahepatic dilatations into type Id, and regrouping Todani type IVa with multiple extrahepatic and intrahepatic dilatations into a type IV based on the morphology of intrahepatic bile duct dilatation (cystic, segmental, or fusiform dilatations). This modification differentiates extrahepatic bile duct dilatation in cases associated with intrahepatic duct dilatation and improves their classification.\u003c/p\u003e \u003cp\u003eVisser et al. have suggested that the Todani classification system actually encompasses four different diseases in terms of their pathogenesis, risk of malignancy, natural history, and treatment, and thus proposed describing these entities as congenital choledochal cyst, choledochocele, choledochal diverticulum, and Caroli's disease [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Many researchers have subsequently supported this approach [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. However, these four diseases have similar clinical features and generally similar treatments (with the exception of Caroli's disease), so they can be differentiated but not necessarily be completely independent, which seems to over-exaggerate the differences of each type [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDong et al. also concluded that the Todani classification was cumbersome, did not consider pathological results, and was confusing regarding the classification of extrahepatic bile duct dilatation, which led them to propose a new system based on anatomical and clinicopathological features from analysis of plenty of data and clinical practices [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Their system combines cases that only involve the extrahepatic bile ducts, subdivides Todani type IVa, and classifies intrahepatic dilatation as involving the peripheral or central hepatic ducts, with further classification according to the extent of liver involvement. Thus, the Biliary Surgery Group of the Chinese Society of Medical Surgery acknowledged in 2017 that this classification system was useful for guiding the surgical strategy. However, Dong's exhaustive classification system is complicated to remember and apply, which is a challenge in primary hospitals, and this system includes some overlap in terms of treatment strategy, with unclear boundaries. Moreover, Dong's classification system does not cover cases with extrahepatic dilatation plus intrahepatic distal dilatation\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e4.2 HUAXI CBD classification\u003c/h2\u003e \u003cp\u003eAlthough each of these classifications has its own rationale and innovations, and has more or less improved the CBD classification, problems remain. Firstly, these classifications are not comprehensive, especially given that underage CBD patients account for 75% of all BD cases, but almost all of these classifications are based on adult patients, of which secondary BD accounts for a\u003c/p\u003e \u003cp\u003elarge proportion, and the morbidity, imaging features, risk of malignancy and prognosis of secondary BD are significantly different compared to CBD [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In addition, with the development of imaging methods, currently commonly used imaging techniques such as abdominal ultrasonography, CT, MRI, MRCP, intraoperative cholangiography, and cholangioscopy have greatly assisted clinical diagnosis and treatment, and demand a more modern classification. Among these options, although MRCP is susceptible to interference and has a high false positive rate in cases with bile duct stones, it is considered the best modality for diagnosing and evaluating CBD at present, due to its noninvasive, highly sensitive and specific, allows clear visualization of hepato-pancreato-biliary structures, which can guide the procedure and reduce the number of invasive operations[\u003cspan additionalcitationids=\"CR20 CR21\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Cholangiography is highly sensitive and can directly identify dilatation inside and outside the liver, which aid in classification and can help identify intrahepatic bile duct stenosis to guide surgery. Intraoperative cholangioscopy can assist in determining secondary or primary intrahepatic BD, and directly visualizing and measuring the caliber of its stenotic segment with a microscope [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. It can also be supplemented with endoscopic ultrasound to detect the intrahepatic ducts more clearly, with sensitivity and specificity up to 90% and 93%, and in cases of combined stone formation, lithotripsy, stone extraction and flushing can be performed simultaneously (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e) [\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Based on the shortcomings of the above classification and the advantages of the current imaging techniques, as well as the clinical experience of our team in treating minor CBD cases, we proposed the HUAXI CBD classification. Inspired by the concept of \"central hepatic duct\" in Dong's classification, CBD is divided into four types, each with distinctive treatment characteristics.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe basic principles for treating BD involve resection of the dilated bile duct(s), relief of secondary symptoms, and restoration of bile flow [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Thus, in this research, patients with HUAXI type I, II and III CBD underwent complete resection of the dilated extrahepatic bile duct and a high Roux-en-Y hepaticojejunostomy, with the anastomosis made as large as possible to reduce the incidence of postoperative stenosis. Types II, III, and IV, because they involve hilar or intrahepatic bile duct dilatation, should be resected or shaped for stenoses that can be explored in the portal region, while for intrahepatic intrahepatic stenosis, close long-term postoperative follow-up is needed to pay attention to cholelithiasis and possible development of cholangiocarcinoma [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Type III and IV intrahepatic dilatation may be confined to a single LL, but more often the dilatations are widely distributed throughout the liver. For children with lesions mainly confined to a single lobe, complicated by recurrent intrahepatic stones and cholangitis, lobectomy can be considered. In cases where the lesion involves the whole liver, especially in Caroli's disease, which is often associated with genetic abnormalities and rapid progression of liver fibrosis, there is no curative surgical option and liver transplantation is usually considered.\u003c/p\u003e \u003cp\u003eOverall, our experience showed that for HUAXI type I CBD, where the lesion involves only the extrahepatic ducts, the surgery is not difficult, with few complications and favorable recovery of liver function, especially in recent years with the popular use of laparoscopic and robot-assisted technology, the surgery is less traumatic and faster recovery. In HUAXI CBD type II, there is definite stenosis at the porta hepatis, requiring hilar cholangioplasty, which may be caused by the independent development of the intrahepatic and extrahepatic bile ducts during the embryonic period [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Nevertheless, most immature patients with type II experience have symptomatic relief and better prognosis than those in adults, after complete resection of the hilar stenosis. In type III and IV cases with limited resectable intrahepatic lesions, a better prognosis can be obtained. However, Caroli's disease is often associated with genetic disorder and can progress rapidly to hepatic fibrosis, and in about 50% of cases is combined with renal cystic lesions or medullary spongy kidneys. In these cases, hepaticojejunostomy or puncture and drainage of the intrahepatic lesion can only delay disease progression, which is inevitably followed by liver failure, and the only effective option is liver transplantation [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe rate of post-treatment complications varied among patients with different types of HUAXI CBD classification. The most common early complication was bile leak (6.7%), mainly seen in type I and type II patients, which may be related to the early lack of experience in laparoscopic surgery, resulting in poor suturing and excessive anastomotic tension, but gradually decreased with the accumulation of surgical techniques and experience. Cholangitis was the most common long-term complication (9.7%), with 6/10 and 2/2 in type III and IV cases, respectively. Biliary stenosis with stones Biliary stenosis with stones was also a highly prevalent long-term complication (6.3%), and can occured in all types of patients, with a higher incidence in types III and IV cases. Stones are often removed by surgical incision or choledochoscopy. Literature has also reported good results in pediatric patients using small-sized ureteroscopes to remove the stones [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. The occurrence of cholelithiasis and cholangitis is considered closely related to intrahepatic bile duct stenosis, and alternating stenosis and dilatation are morphological features underlying the occurrence of cholangitis and cholelithiasis, which is consistent with our clinical experience [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, the feature of single-center retrospective study and small number of type III and IV cases may have biased the data and affected the authenticity of the results. We are currently conducting a multicenter collaboration with three hospitals to conduct prospective trials to test the use of this classification.\u003c/p\u003e \u003cp\u003eIn summary, the CBD classification current commonly used in clinical practice is not suitable to CBD patients who are mainly minors, and suffers from the problems of complicated classification, unfavorable to memory and clinical application. Therefore, our team proposed the HUAXI CBD classification based on preoperative imaging features and treatment strategies. The classification is consistent with the treatment principles of CBD, with clear and concise demarcation of each type, and easy to remember. Moreover, the type of each patient can be determined by preoperative imaging data, which helps to guide the operation. The classification can then be further determined by intraoperative imaging data, which helps in subsequent treatment. In conclusion, HUAXI CBD classification is more suitable for the clinical application of CBD patients.\u003c/p\u003e \u003c/div\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCBD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eCongenital biliary dilatation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRCP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic resonance cholangiopancreatography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eComputed tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emagnetic resonance imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePTCD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003epercutaneous transhepatic cholangial drainage\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLL\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLiver lobe\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e \u003cp\u003e This study was approved by the ethics committee of West China hospital of Sichuan university (approval no.202411). We certify that the study was performed in accordance with the 1964 declaration of HELSINKI and later amendments.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent for publication\u003c/strong\u003e \u003cp\u003e Written informed consent was obtained from the patient for publication of this study and any accompanying images.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis work was supported by the National Natural Science Foundation of China (81571473).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eFirst author: Zhenyu Xie, drafting the work and substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work.Co-first author: Siyu Pu, drafting the work and substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work.Corresponding author: Shuguang Jin, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved, and Final approval of the version to be published.Author: Bo Xiang, reviewing the work critically for important intellectual content.Author: Jiayin Yang, reviewing the work critically for important intellectual content.Author: Lvnan Yan, reviewing the work critically for important intellectual content.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets [ANALYZED] analyzed for this study can be found in the Chinese Clinical Trial Registry. ( ChiCTR1900026446 )\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eTodani T, Watanabe Y, Narusue M, Tabuchi K, Okajima K. Congenital Bile Duct Cysts: Classification, Operative Procedures, and Review of Thirty-Seven Cases Including Cancer Arising from Choledochal Cyst. Am J Surg - AMER J SURG. 1977;134:263\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYamaguchi M. Congenital choledochal cyst. Analysis of 1,433 patients in the Japanese literature. Am J Surg. 1980;140:653\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKhan S, Nagorney D. Bile duct cysts in adults. Volume. 2012;1:707\u0026ndash;e718702.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eO'Neill JA. Choledochal cyst. Curr Probl Surg. 1992;29(6):361\u0026ndash;410.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYoon J-H. Magnetic resonance cholangiopancreatography diagnosis of choledochal cyst involving the cystic duct: Report of three cases. Br J Radiol. 2011;84:e18\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlonso-Lej F, Rever W, Pessagno D. A study of the congenital choledochal cyst with a report of two patients and an analysis of 94 cases. Surg Gynec Obstet 1959, 1.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDong J, Zheng X, Xia H, Zhao X, Liang B, Yang T, Zeng J, Huang Z. Cystic dilation of bile duct: new clinical classification and treatment strategy. Chin J Dig Surg 2013(5):370\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVisser BC, Suh I, Way LW, Kang S-M. Congenital Choledochal Cysts in Adults. Arch Surg. 2004;139(8):855\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLenriot JP, Gigot JF, S\u0026eacute;gol P, Fagniez PL, Fingerhut A, Adloff M. Bile duct cysts in adults: a multi-institutional retrospective study. French Associations for Surgical Research. Ann Surg. 1998;228(2):159\u0026ndash;66.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGadelhak N, Shehta A, Hamed H. Diagnosis and management of choledochal cyst: 20 years of single center experience. World J gastroenterology: WJG. 2014;20:7061\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDesmet VJ. Ludwig symposium on biliary disorders\u0026ndash;part I. Pathogenesis of ductal plate abnormalities. \u003cem\u003eMayo Clinic proceedings\u003c/em\u003e 1998, 73(1):80\u0026ndash;89.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParada LA, Hallen M, Hagerstrand I, Tranberg KG, Johansson B. Clonal chromosomal abnormalities in congenital bile duct dilatation (Caroli's disease). Gut. 1999;45(5):780\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu KL, Changchien CS, Kuo CM, Chuah SK, Chiu YC, Kuo CH. Caroli's disease - a report of two siblings. Eur J Gastroenterol Hepatol. 2002;14(12):1397\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTodani T. Congenital choledochal dilatation: Classification, clinical features, and long-term results. J Hepato-biliary-Pancreat Surg. 1997;4(3):276\u0026ndash;82.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWiseman K, Buczkowski AK, Chung SW, Francoeur J, Schaeffer D, Scudamore CH. Epidemiology, presentation, diagnosis, and outcomes of choledochal cysts in adults in an urban environment. Am J Surg. 2005;189(5):527\u0026ndash;31. discussion 531.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHuang CS, Huang CC, Chen DF. Choledochal Cysts: Differences Between Pediatric and Adult Patients. J Gastrointest Surg. 2010;14(7):1105\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStain S, Guthrie C, Yellin A, Donovan A. Choledochal Cyst in the Adult. Ann Surg. 1995;222:128\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu C-L, Fan S-T, Lo C-M, Lam C-M, Poon R, Wong J. Choledochal cysts in adults. Archives Surg (Chicago Ill: 1960). 2002;137:465\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eThe group of Biliary SoS. Chinese Medical Association Guideline for the diagnosis and treatment for biliary dilatation (2017 edition). Chin J Dig Surg. 2017;16(8):767\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSacher V, Davis J, Sleeman D, Casillas J. Role of magnetic resonance cholangiopancreatography in diagnosing choledochal cysts: Case series and review. World J Radiol. 2013;5:304\u0026ndash;12.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKamisawa T, Tu Y, Egawa N, Tsuruta K, Okamoto A, Kamata N. MRCP of congenital pancreaticobiliary malformation. Abdom Imaging. 2007;32(1):129\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen Y, Pleskow D. SpyGlass single-operator peroral cholangiopancreatoscopy system for the diagnosis and therapy of bile-duct disorders: A clinical feasibility study (with video). Gastrointest Endosc. 2007;65:832\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYoo K-S, Lehman G. Endoscopic Management of Biliary Ductal Stones. \u003cem\u003eGastroenterology clinics of North America\u003c/em\u003e 2010, 39:209\u0026ndash;227, viii.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStavropoulos S, Larghi A, Verna E, Battezzati P, Stevens P. Intraductal Ultrasound for the Evaluation of Patients with Biliary Strictures and No Abdominal Mass on Computed Tomography. Endoscopy. 2005;37:715\u0026ndash;21.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarrell R, Agarwal B, Brandwein S, Underhill J, Chuttani R, Pleskow D. Intraductal US is a useful adjunct to ERCP for distinguishing malignant from benign biliary strictures. Gastrointest Endosc. 2002;56:681\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJan Y-Y, Chen H-M, Chen M-F. Malignancy in choledochal cysts. Hepatogastroenterology. 2000;49:100\u0026ndash;3.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoskams T, Desmet V. Embryology of Extra- and Intrahepatic Bile Ducts, the Ductal plate. \u003cem\u003eAnatomical record (Hoboken, NJ\u003c/em\u003e: 2007) 2008, 291:628\u0026ndash;635.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSato Y, Ren X, Nakanuma Y. Caroli's Disease: Current Knowledge of Its Biliary Pathogenesis Obtained from an Orthologous Rat Model. \u003cem\u003eInternational journal of hepatology\u003c/em\u003e 2012, 2012:107945.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDrenth J, Chrispijn M, Bergmann C. Congenital fibrocystic liver diseases. Best Pract Res Clin Gastroenterol. 2010;24:573\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePonsky L, Geisinger M, Ponsky J, Streem S. Contemporary \u0026lsquo;Urologic\u0026rsquo; intervention in the pancreaticobiliary tree. Urology. 2001;57:21\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTodani T, Narusue M, Watanabe Y, Tabuchi K, Okajima K. Management of Congenital Choledochal Cyst with Intrahepatic Involvement. Ann Surg. 1978;187:272\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bped","sideBox":"Learn more about [BMC Pediatrics](http://bmcpediatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bped/default.aspx","title":"BMC Pediatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"congenitial biliary dilation, classification, imaging, diagnosis, prognosis","lastPublishedDoi":"10.21203/rs.3.rs-4425208/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4425208/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eTo propose a more concise and more suitable classification of congenital biliary dilatation (CBD), and exploring the feasibility and effectiveness of this classification in diagnosis and treatment.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e Based on the preoperative imaging data of patients with CBD admitted to the Department of Pediatric Surgery of West China Hospital of Sichuan University, from January 2015 to December 2018, a new classification of CBD was accomplished according to the site of bile duct dilatation lesions, which was named HUAXI CBD classification. The CBD was classified into 4 types: type Ⅰ (distal extra-hepatic bile duct dilatation), type Ⅱ (distal extra-hepatic combined with right and left primary hepatic bile duct dilatation), type Ⅲ (extra-hepatic combined with secondary and above hepatic bile duct dilatation), and type Ⅳ (intra-hepatic bile duct dilatation). Meanwhile, the feasibility and reliability of the HUAXI CBD classification were analyzed by analyzing the clinical treatment strategies, perioperative complications and long-term follow-up results of different subtypes.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eA total of 300 patients with CBD were included in this study. According to the HUAXI CBD classification method, 240 cases were type Ⅰ, 48 cases were type Ⅱ, 10 cases were type Ⅲ, and 2 cases were type Ⅳ. For type Ⅰ, 236 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy and 4 cases were treated non-operatively; For type Ⅱ, 48 patients underwent cholecystectomy, central hepatic duct reconstruction and Roux-en-Y hepaticojejunostomy; For type Ⅲ, 9 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy, 5 of which had intrahepatic dilatation confined to part of the liver lobe and underwent partial hepatectomy with intra-hepaticojejunostomy. One case was treated with percutaneous transhepatic cholangial drainage (PTCD) only; two type Ⅳ patients were treated with PTCD only. Patients with type Ⅰ had a normal hepatobiliary function after surgery and a good prognosis; patients with type Ⅱ had good recovery of liver function in 37 cases (77.1%), but 11 cases (22.9%) had postoperative complications during follow-up; patients with type Ⅲ and Ⅳ had high incidence of cholangitis (6/10, 2/2, respectively) and choledocholithiasis (5/10, 2/2, respectively) after surgery, especially those with diffuse intrahepatic dilatation having a poor prognosis, eventually developing cirrhosis and necessitating liver transplantation.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThe HUAXI CBD classification is consistent with treatment principles, concise and easy to remember, and more suitable for CBD clinical application.\u003c/p\u003e","manuscriptTitle":"A new clinical classification of congenital biliary dilatation HUAXI CBD classification","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-18 15:26:36","doi":"10.21203/rs.3.rs-4425208/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-06-19T10:32:58+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-19T08:59:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-06-19T08:58:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pediatrics","date":"2024-05-15T12:39:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bped","sideBox":"Learn more about [BMC Pediatrics](http://bmcpediatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bped/default.aspx","title":"BMC Pediatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1f77f85b-8279-4f91-a288-587c086e8e9a","owner":[],"postedDate":"July 18th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-11-25T16:01:57+00:00","versionOfRecord":{"articleIdentity":"rs-4425208","link":"https://doi.org/10.1186/s12887-024-05220-0","journal":{"identity":"bmc-pediatrics","isVorOnly":false,"title":"BMC Pediatrics"},"publishedOn":"2024-11-19 15:57:36","publishedOnDateReadable":"November 19th, 2024"},"versionCreatedAt":"2024-07-18 15:26:36","video":"","vorDoi":"10.1186/s12887-024-05220-0","vorDoiUrl":"https://doi.org/10.1186/s12887-024-05220-0","workflowStages":[]},"version":"v1","identity":"rs-4425208","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4425208","identity":"rs-4425208","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}