Postoperative abdominopelvic adhesion and umbilical wound validation after single-port laparoscopy or two-port laparoscopy for gynecological surgery: a comparison with conventional laparoscopy.

Because the incidence of postoperative intraperitoneal umbilical adhesion increases as the size of the umbilical wound increases, surgical umbilical wounds after single-port laparoscopic surgery should be repaired with caution. A second laparoscopic surgery should be carefully performed after a previous single-port laparoscopic surgery to avoid causing organ damage due to contact with adhesions when entering the umbilical port.

A total of 134 patients were separated into three groups, and their clinical data were analyzed. Ninety-two patients (68.7%) had no operation history, 22 patients (16.4%) had a history or one or more cesarean section, 9 patients (6.7%) had a history of gynecological laparoscopy, 5 patients (3.7%) had a history of gynecological laparotomy, 6 patients (4.5%) had a history of appendectomy, and 1 patient (0.7%) had a history of bowel surgery. One patient had a history of appendectomy and left salping-oophorectomy. Thirteen patients underwent single-port laparoscopic surgery, 53 patients underwent two-port laparoscopic surgery, and 68 patients underwent three-port or four-port laparoscopic surgery. One hundred twenty-eight patients (95.5%) underwent laparoscopic adnexal surgery, 4 patients (3.0%) underwent total laparoscopic hysterectomy (TLH), and 2 patients (1.5%) underwent laparoscopy-assisted vaginal hysterectomy (LAVH). The indications for surgery were adnexal mass in 52 patients (38.8%), endometriosis in 33 patients (24.6%), ectopic pregnancy in 23 patients (17.2%), tubo-ovarian abscess or inflammation in 8 patients (6.0%), hydrosalpinx in 6 patients (4.5%), myoma or adenomyosis in 4 patients (1.3%), ovarian or tubal cancer in 3 patients (2.2%), carcinoma in situ of the cervix in 2 patients (1.5%), and ovarian hyperstimulation syndrome (OHSS) in 1 patient (0.7%). Patients who underwent single-port laparoscopy were included in Group 1 ( n  = 13), patients who underwent two-port laparoscopy were included in Group 2 ( n  = 53), and patients who underwent three-port laparoscopy or four-port laparoscopy were included in Group 3 ( n  = 68). The patients’ age, parity, height, weight, and body mass index (BMI) were not significantly different (Table  1 ). Moreover, there were no significant differences among the study groups in terms of preoperative pelvic adhesion scores, postoperative pelvic adhesion scores, hemoglobin changes, or the occurrence of an umbilical hernia. Table 1 Clinical characteristics of the study groups (means ± SDs) Group Age (yrs.) Parity Height (cm) Weight (kg) BMI (kg/m 2 ) 1 30.4 ± 11.0 0.6 ± 1.0 159.7 ± 6.3 60.7 ± 12.0 23.7 ± 4.0 2 32.4 ± 7.4 0.6 ± 0.9 160.6 ± 5.4 59.7 ± 12.8 23.2 ± 5.1 3 33.6 ± 9.3 0.9 ± 1.1 160.1 ± 5.0 58.4 ± 10.0 22.8 ± 3.7 Clinical characteristics of the study groups (means ± SDs) The differences in the preoperative white blood cell (WBC) count, postoperative white blood cell (WBC) count, need for surgical drainage tube insertion, postoperative hospital stay, operative interval, and intraperitoneal umbilical adhesion score were significantly different among the study groups (Table  2 ). Table 2 Perioperative and postoperative outcomes of the study groups (means ± SDs) Group Op time (min) Adhesion score (preop) Adhesion score (postop) Hb change (g/dl)* Preop WBC (/ul) Postop WBC (ul) Postop hospital stay (days) Umbilical adhesion score Umbilical hernia 1 77.5 ± 30.3 1.2 ± 1.2 1.0 ± 1.4 1.7 ± 0.8 6553.8 ± 2269.2 7115.4 ± 2096.0 3.3 ± 0.8 0.5 ± 0.9 None 2 75.2 ± 28.6 1.9 ± 2.2 2.2 ± 2.7 1.8 ± 1.1 9943.4 ± 5114.6 7222.6 ± 2983.8 4.6 ± 1.8 0.2 ± 0.6 1 case 3 83.3 ± 34.6 2.0 ± 2.2 2.4 ± 2.2 1.9 ± 0.8 6575.0 ± 2397.5 6041.8 ± 1965.9 4.2 ± 1.3 0.1 ± 0.3 1 case *Changes in hemoglobin (Hb) levels were calculated as the difference between the preoperative hemoglobin level and the postoperative 2-day hemoglobin level Perioperative and postoperative outcomes of the study groups (means ± SDs) *Changes in hemoglobin (Hb) levels were calculated as the difference between the preoperative hemoglobin level and the postoperative 2-day hemoglobin level A comparison of Group 1 and Group 3 revealed that the differences in postoperative white blood cell count, length of surgical drainage tube insertion, length of postoperative hospital stay, intraperitoneal umbilical adhesion score, and postoperative pelvic adhesion score were statistically significant. Among the enrolled patients, single-port laparoscopy was not performed for patients with intraperitoneal inflammatory diseases such as tubo-ovarian abscess. The postoperative hospital stay of Group 3 was longer than that of Group 1 because of antibiotic therapy, and the postoperative white blood cell count of Group 3 was greater than that of Group 1 because of inflammatory conditions. A comparison of Group 2 and Group 3 revealed that the differences in the preoperative white blood cell count, postoperative white cell count, and reoperation interval were statistically significant. Moreover, there were no significant differences between Group 2 and Group 3 in terms of the preoperative pelvic adhesion score, postoperative pelvic adhesion score, hemoglobin changes, intraperitoneal umbilical adhesion score, or occurrence of umbilical hernia. The correlations between the number of ports used during surgery, the white blood cell (WBC) count before and after surgery, the reoperation interval, and the intraperitoneal umbilical adhesion score were also analyzed (Table  2 ). The length of postoperative hospital stay, incidence of umbilical hernia, and the difference between the preoperative and postoperative pelvic adhesion scores were not correlated with the number of ports used during surgery. The correlations between preoperative and postoperative pelvic adhesion scores and the intraperitoneal umbilical adhesion score, number of ports used during surgery, white blood cell (WBC) count after surgery, and incidence of umbilical hernia were also evaluated (Table  3 ). Hemoglobin changes, white blood cell (WBC) counts before surgery, postoperative hospital stays, and reoperation intervals were not correlated with the number of ports used during surgery. Table 3 Correlation with postoperative umbilical adhesion sores Surgical factors Pearson’s correlation coefficient p value Port number − 0.22 0.01* Adhesion score (AS) difference (Postop. AS—Preop. AS) 0.22 0.10* Umbilical hernia 0.34 0.00* *Statistically significant Correlation with postoperative umbilical adhesion sores *Statistically significant In the logistic regression analysis for risk factor analysis, the preoperative WBC count (odds ratio = 1.0, p value = 0.043) was analyzed as a risk factor for umbilical adhesion. On this basis, to exclude adhesion formation risk factors such as inflammation, 102 patients and 32 cases that were excluded from the study group due to inflammatory diseases such as abscesses or preoperative elevated white blood cell counts (> 10,000/µl) were analyzed. The correlation analysis between the number of ports used during operative procedures and umbilical wound adhesion, postoperative white blood cell count, preoperative pelvic adhesion score, postoperative adhesion score, and difference between preoperative and postoperative adhesion scores, only umbilical adhesion (Pearson's correlation coefficient = − 0.22, p value = 0.024) was significant. Because single-port laparoscopic surgery tends not to be performed in patients with inflammatory diseases such as pelvic abscess, correlation analysis revealed that the port number was positively correlated with the WBC count before and after surgery. However, even in an analysis excluding inflammatory risk factors, there was a negative correlation between umbilical adhesions and the number of ports used during laparoscopic surgery. The incidence of intraperitoneal umbilical adhesions increased as the number of ports used during laparoscopy decreased, and the size of the umbilical incision was greater than that used for conventional laparoscopy.

A retrospective cohort study of data obtained from the medical records and radiological studies of patients who underwent laparoscopic surgery at a teaching hospital in Korea between January 1996 and July 2022 was conducted. This study was approved by the institutional review board of our hospital (GNAH 2022-08-019). From January 1996 to July 2022, 4510 patients underwent gynecological laparoscopic surgery. Among these patients, 154 underwent laparoscopic surgery or laparotomy after laparoscopic surgery. Twenty of the 154 patients were excluded because their intraperitoneal outcomes could not be analyzed because the operation records or operation images were not preserved. A total of 134 patients were enrolled in this retrospective cohort study to analyze their intraperitoneal outcomes (Fig.  1 ). Fig. 1 The flow diagram of this study The flow diagram of this study In this retrospective clinical study, the postoperative states of the pelvic and abdominal cavities of patients who underwent consecutive laparotomy or laparoscopic surgery were evaluated for separate reasons after laparoscopic surgery. The patients were divided into groups, which were compared and analyzed on the basis of the number of ports used intraoperatively. The patients were divided into three groups: Group 1 (single-port laparoscopy), Group 2 (two-port laparoscopy), and Group 3 (laparoscopy with three or more ports). We used a custom-made glove port at the umbilical incision site for single-port laparoscopic surgery. An approximately 2 cm skin incision was made in the umbilical area, penetrating the abdominal cavity. An extra small Alexis® wound retractor (Applied Medical, Rancho Santa Margarita, CA, USA) was placed in the umbilical incision. Three trocars (two 12-mm trocars and one 5-mm trocar) were inserted into separate fingers of a surgical glove and secured with rubber bands. The wrist portion of the glove covered the wound retractor, and three Babcock clamps were placed on the edges of the retractor to prevent carbon dioxide leakage. A 10-mm laparoscope and atraumatic forceps were inserted through the umbilical multichannel port. In two-port laparoscopic surgeries, the umbilical skin incision was extended to approximately 1.5 cm, which was sufficiently wide to allow the passage of an index finger. An extra small Alexis® wound retractor (Applied Medical, Rancho Santa Margarita, CA, USA) was placed in the umbilical incision. Two 12-mm trocars were inserted into separate fingers of a No. 6 surgical glove and secured with rubber bands, and the other three fingers of the glove were tied together. An ancillary 5-mm trocar was placed low in the left abdomen under laparoscopy. An umbilical incision was made, and a trocar was inserted through the incision site with or without pneumoperitoneum via a Veress needle. Ancillary 12-mm, 10-mm, or 5-mm trocars were inserted low in the right and left abdomens under laparoscopic observation through the umbilical port. In the conventional laparoscopy group, the ancillary port site low in the abdomen was extended to remove surgical specimens if necessary. A wound retractor was not used in the three-port laparoscopic procedure. Following a review of the medical records and radiological studies, the clinicopathological characteristics of the patients, such as age, parity, previous medical and surgical history, and operative outcomes, such as the operative time, pre- and postoperative white blood cell (WBC) counts, change in the hemoglobin (Hb) level, and postoperative hospitalization duration, were investigated. The operative outcomes of the patients were obtained from their medical records, and the operation records, including those of consecutive operations, were analyzed. The adhesion score and umbilical outcome scale were used to assess the degree of pelvic adhesion and intraperitoneal umbilical adhesion or hernia before and after laparoscopy. Ichikawa et al. investigated the accuracy and clinical value of the adhesion scoring system using transvaginal ultrasonography of endometriotic adhesions and concluded that the adhesion scoring system accurately predicted the status of pelvic adhesions as well as the occurrence of postoperative adhesions and infertility [ 10 ]. With this information, we used the adhesion scoring system to validate the status of pelvic adhesions preoperatively and postoperatively. The degree of intraperitoneal adhesion under the umbilical area was graded using the revised scoring system shown in Fig.  2 . Fig. 2 Pelvic cavity adhesion score and umbilical outcome scale score Pelvic cavity adhesion score and umbilical outcome scale score The results were analyzed via IBM SPSS® version 28 statistical software (IBM, Armonk, NY, USA). Continuous variables were compared via Student’s t test. Categorical variables were compared via the chi-square test or the Kruskal‒Wallis test. All tests were two-sided, and p values ≤ 0.05 were considered significant.

Owing to the increasing interest in minimally invasive surgery, single-port laparoscopic surgery has been used in gynecologic surgeries in many hospitals. Single-port laparoscopic surgery has several limitations in terms of efficacy because surgical instruments must be inserted into the same umbilical port at the same time. Thus, surgeons need time to learn how to adequately perform single-port laparoscopic surgery. In many studies, single-port laparoscopic surgery is suggested to be a safe surgical procedure that yields better cosmetic effects than conventional laparoscopic surgery using multiple ports. Single-port laparoscopic surgery is difficult to perform, and little is known about its learning curve and the factors associated with its operative outcomes during the learning period [ 11 ]. Single-port laparoscopic surgery has become well-known as a minimally invasive surgery among both operators and patients because there is only one postoperative wound. In a review, the authors concluded that single-port surgery has many potential benefits, but comparative trials have shown no differences between single-port surgery and conventional laparoscopy in terms of postoperative complications, postoperative pain, hospital stay, or cosmetic results [ 12 ]. However, several studies have reported that single-port laparoscopic surgery is superior to conventional laparoscopic surgery in terms of surgical prognosis. It is considered to have better cosmetic outcomes because of the presence of one postoperative wound, which is hidden within the umbilicus, but there are few objective studies on this topic. We found that when laparoscopic surgery was performed on patients who had previously undergone single-port laparoscopic surgery, there were more empirical findings of intraperitoneal adhesions under the umbilicus than in patients who underwent conventional laparoscopic surgery. Therefore, this study was designed to compare the incidence of intraperitoneal adhesions, including those around the umbilicus, after single-port laparoscopy surgery with that after two-port laparoscopy and conventional laparoscopic surgery. Postoperative adhesions, such as the band of connective tissue that joins two normally separate anatomical structures, occur in 75% to 93% of patients who undergo gynecological surgeries and are the most common sequelae. These findings may lead to chronic pain, infertility, or bowel obstruction [ 1 , 13 ]. Therefore, the development of postoperative adhesions between the pelvis and the abdominal cavity is a concern among surgeons. Adhesions are the result of surgical tissue trauma and healing. Therefore, adhering to the principles of microsurgery and minimally invasive surgery may help decrease the incidence of postoperative adhesions [ 6 ]. In one observational study, the use of an adhesion barrier around the port site prior to fascia closure prevented postoperative adhesion in benign single-port laparoscopic surgery. However, the study had some limitations in terms of adhesion evaluation and postoperative intervals because adhesions were evaluated using visceral sliding techniques during transabdominal sonography after three months [ 14 ]. Several studies have evaluated the occurrence of pelvic adhesions after surgery, and most have used imaging tests. Gerner-Rasmussen et al. reviewed the literature to investigate the usefulness of noninvasive diagnostic methods for detecting intraabdominal adhesions [ 15 ]. This approach has limitations in reflecting the actual condition of the pelvis and abdominal cavity, and visual confirmation through surgery is the most accurate way to determine the degree of adhesion. However, this approach is not feasible in most clinical settings unless patients need to undergo additional laparoscopy for therapeutic purposes. Therefore, we retrospectively evaluated the occurrence of adhesions in patients who underwent laparotomy or laparoscopy following laparoscopy. The tool currently available for evaluating the degree of adhesion is a visual adhesion scoring system. Ichikawa et al. investigated the accuracy and clinical value of the adhesion scoring system using transvaginal ultrasonography for endometriotic adhesion [ 10 ]. The authors concluded that the adhesion scoring system accurately predicts the pelvic adhesion status and can predict the occurrence of postoperative adhesions and infertility. With this information, we used the adhesion scoring system to validate the pelvic adhesion status preoperatively and postoperatively. The degree of intraperitoneal adhesion under the umbilical area was graded via the revised scoring system shown in Fig.  2 . Many large-scale meta-analyses on single-port laparoscopic surgery have been conducted and published. Many studies have compared conventional laparoscopic surgery and single-port laparoscopic surgery for cholecystectomy and inguinal herniorrhaphy. In conclusion, most studies have shown that single-port laparoscopic surgery has no problem in terms of surgical efficacy and that the surgical prognosis is similar to that of conventional laparoscopic surgery. Several systemic reviews and randomized clinical trials of gynecological surgeries have been performed. Bonollo et al. reported a systemic review of randomized clinical trials for laparoendoscopic single-site surgery (LESS) in gynecology [ 16 ]. In their review, they showed that although cosmetic results are intuitively the main advantage of the LESS technique, current evidence does not seem to demonstrate that LESS is clearly superior to conventional multiport laparoscopy for benign gynecological conditions. Gasparri et al. performed a meta-analysis of conventional versus single-port laparoscopy for the surgical treatment of ectopic pregnancy [ 17 ]. They concluded that LESS does not seem to be superior to conventional laparoscopy in terms of the management of ectopic pregnancies. In a report on the long-term application of single-port and multiport total laparoscopic hysterectomy (TLH) in a single center, the authors concluded that some surgical outcomes of single-port TLH significantly improved after long-term observation, as laparoscopic surgical instruments and surgeon skill improved [ 18 ]. In their study, although the uterine weight of the single-port TLH group was lower than that of the multiport TLH group, single-port TLH was associated with a significantly shorter hospital stay and operative time, a lower Hb change, and a lower complication rate after correction for biases. In another meta-analysis of single-port TLH versus multiport TLH, the authors revealed that single-port TLH is a feasible, safe and effective technique for benign gynecologic conditions, although the operative time may be longer than that of multiport TLH [ 19 , 20 ]. No clinically relevant advantages were identified, and as no data on cost effectiveness are available, there are currently not enough valid arguments to broadly implement LESS for hysterectomy. Regarding the wound complications in 1145 consecutive transumbilical single-incision laparoscopic procedures published by Weiss et al., the authors stated that the incidence of wound complications in transumbilical single-incision surgery is relatively acceptable and that this rate further decreases as surgeons become proficient [ 21 ]. In a study on the incidence of and risk factors for incisional hernia after single-incision endoscopic surgery, Guzmán et al. reported that single-incision laparoscopic cholecystectomy was significantly associated with postoperative incisional hernia [ 22 ]. Casaccia et al. also conducted a comparative study between single-port laparoscopic surgery and conventional laparoscopic surgery for gallbladder removal and reported that single-port laparoscopic surgery is a safe and effective surgical method when performed by an operator who is familiar with the procedure. In a recent review of laparoscopic appendectomy with single-port vs. conventional access, twenty-one randomized controlled trials were reviewed [ 23 ]. Although single-port laparoscopic appendectomy is associated with fewer postoperative wound infections, it is associated with a significantly longer operation time. The risk of postoperative general complications is still present. Meta-analyses of cosmetic outcomes, scar formation, or postoperative pain were not performed because different scales were used in each study. Single-port laparoscopic surgery is recognized for its cosmetic superiority over conventional laparoscopic surgery, but the operator must pay attention to fascial suturing because of the increased potential for hernia development [ 24 ]. Owing to the correlation between wound size and the degree of adhesion, even if there are a small number of wounds, the risk of adhesion and wound complications may increase if the wound size is large. From a cosmetic perspective, having fewer wounds may be an advantage, but minimal wounds are a true advantage of minimally invasive surgery. Our study has several limitations. First, the number of patients who underwent single-port laparoscopic surgery was the lowest among the three study groups, which limits the comparative nature of the study. Because single-port laparoscopic surgery has only recently been performed, there is a limitation in that there are only a few cases in which intraperitoneal evaluation was performed through subsequent reoperations. Second, because the sizes of the umbilical ports used in single-port laparoscopic surgery and two-port laparoscopic surgery are similar and because the incision size is not accurately measured, comparisons of the differences between single-port laparoscopic surgery and two-port laparoscopic surgery are limited. Third, the degree of intrapelvic adhesion and intraperitoneal umbilical adhesion after surgery was evaluated on the basis of the adhesion score obtained during reoperation, which has several limitations because it is difficult to exclude adhesion factors other than surgical variables such as inflammation. There are several strengths of our study. First, an objective evaluation tool, such as the adhesion scoring system, was used to evaluate wound prognosis after single-port or two-port laparoscopic surgery through visual confirmation following reoperation. Second, although the prognosis of laparoscopic surgery was not compared in a prospective study, surgical prognosis after single-port, two-port or conventional laparoscopic surgery was compared retrospectively by setting up appropriate comparison groups. The incidence of postoperative intraperitoneal umbilical adhesion increases as the size of the umbilical wound increases, such as after a single-port laparoscopy. Therefore, surgical umbilical wounds after single-port laparoscopic surgery should be repaired with caution. A second laparoscopic surgery should be carefully performed after a previous single-port laparoscopic surgery to avoid causing organ damage due to contact with adhesions when entering the umbilical port. Because the number of study patients who underwent single-port laparoscopic surgery was too small in this study, the analysis of the results was limited, and additional studies with more patients and standardized research methods are needed in the future.

Postoperative adhesions, such as a band of connective tissue that joins two normally separate anatomical structures, occur in 75% to 93% of patients who undergo gynecological surgeries and are among the most common sequelae of gynecological surgeries. These findings may lead to chronic pain, infertility, or bowel obstruction [ 1 , 2 ]. The triggers of adhesion include inflammation, endometriosis, chemical peritonitis, radiotherapy, foreign body reactions and continuous ambulatory peritoneal dialysis, but most adhesions form as a result of surgery [ 3 ]. Studies on the pathogenesis of adhesion formation in animals and humans published over a 50-year span were assessed, leading to the development of a unified concept. Peritoneal damage caused by surgical trauma or other insults evokes an inflammatory response, thereby promoting procoagulatory and antifibrinolytic reactions and a subsequent significant increase in fibrin formation. Importantly, the peritoneal inflammatory status seems to be a crucial factor for determining the duration and extent of the imbalance between fibrin formation and fibrin dissolution and therefore in the persistence of fibrin deposits, determining whether or not adhesions develop [ 4 ]. Depending on their severity and position, postoperative adhesions may be asymptomatic or cause significant morbidity, including bowel obstruction, chronic abdominal pain, female infertility, and increased the difficulty of subsequent surgeries, resulting in notable consequences for patients and surgeons [ 5 ]. Therefore, the development of postoperative adhesions between the pelvis and the abdominal cavity is a concern among surgeons. Adhesions are the result of tissue trauma during surgery and postoperative healing. Therefore, adhering to the principles of microsurgery and minimally invasive surgery may help decrease the incidence of postoperative adhesions [ 6 ]. Laparoscopy is a minimally invasive surgical technique that results in a short recovery time and a quick return to daily life activities. Generally, laparoscopy is a less invasive technique than laparotomy because there is less postoperative scarring, and the recovery time is shorter. Because the abdominal wound scars that develop after laparoscopy are smaller than those that develop after laparotomy are, laparoscopy has been proven to have cosmetic advantages. Recently, with the emergence of minimally invasive surgery, laparoscopic surgery has been developed to reduce the number of ports. Owing to its ability to reduce tissue trauma and improve cosmetic outcomes, single-port laparoscopic surgery is becoming increasingly common [ 7 ]. Single-port laparoscopic surgery has not yet completely replaced conventional laparoscopic surgery because of the difficulties and limitations of the procedure, and the incidence of postoperative wound hernia is higher because the umbilical wound incision used during single-port laparoscopic surgery is larger than that used for conventional laparoscopic surgery. Although single-port laparoscopy has more cosmetic benefits than conventional laparoscopic surgery because of the single incision made in the umbilicus, umbilical hernias are potentially life-threatening and may require emergency surgery due to bowel obstruction or bowel ischemia [ 8 ]. Recently, the vaginal approach has also been shown to have advantages over laparoscopy since it provides a better cosmetic effect and reduces the risks of port-site hernia and pain [ 9 ]. Because the incision used for single-port laparoscopic surgery is larger than that used for conventional laparoscopic surgery, complications such as umbilical hernia may occur, and it is also estimated that the incidence of complications such as port site adhesions and hemorrhage, which are wound complications, is high. Thus, we analyzed postoperative intraperitoneal outcomes after laparoscopy via patient operation records and photographs of consecutive surgeries. A comparative study of single-port laparoscopy, two-port laparoscopy, and laparoscopy with three or more ports was also conducted.