The key role of magnetic resonance sialography in the differential diagnosis between sialolith and phlebolith of the floor of the mouth

The key role of magnetic resonance sialography in the differential diagnosis between sialolith and phlebolith of the floor of the mouth | 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 Case Report The key role of magnetic resonance sialography in the differential diagnosis between sialolith and phlebolith of the floor of the mouth Alvaro Sánchez Barrueco, Gonzalo Díaz Tapia, Félix Guerra Gutiérrez, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6330727/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Oct, 2025 Read the published version in BMC Oral Health → Version 1 posted 13 You are reading this latest preprint version Abstract Background: The confusion between a phlebolith and a sialolith in the floor of the mouth can pose serious surgical risks, making it essential to define appropriate complementary imaging studies. Case presentation: We present the case of a patient with right submandibular sialolithiasis suspected by computed tomography. A previous attempt at extraction in another centre, under local anesthesia, was interrupted due to profuse bleeding, preventing the localization and removal of the calculi. Due to our pre-surgical study protocol using magnetic resonance sialography (MR-Si), a low-flow vascular malformation with internal phleboliths was revealed, without involvement of the salivary duct. As a result, the planned sialendoscopy was cancelled, and a follow-up approach was chosen given the asymptomatic nature of the condition. Conclusions: This case underscores the importance of standardizing radiological studies for salivary gland and floor-of-mouth pathology, highlighting MR-Si for its high sensitivity and specificity. Therefore, MR-Si enables more precise surgical planning and helps prevent unnecessary intraoperative complications. Sialolith Sialolithiasis Phlebolith floor of the mouth magnetic resonance sialography low-flow vascular malformation sialendoscopy sialadenitis Figures Figure 1 Figure 2 Background Sialolithiasis is one of the most common causes of chronic obstructive sialadenitis (COS)( 1 ), which may present as recurrent inflammation of the salivary gland or be an incidental finding in imaging studies. Its prevalence in postmortem studies is estimated at 0.115%( 2 ). The presence of phleboliths in the head and neck region is well-documented in the literature( 3 , 5 – 7 ), predominantly in pediatric patients( 8 , 9 ). Previous reports have described head and neck lesions that may contain internal phleboliths, mimicking sialolithiasis, such as submandibular hemangioma( 3 ) or low-flow vascular malformations (LFVM). LFVMs typically present as soft masses with a tendency toward inflammation or thrombosis( 4 ), with the potential to develop phleboliths. The inflammatory nature of LFVMs, sometimes exacerbated by meals, combined with imaging findings suggestive of sialolithiasis, often leads to a misdiagnosis of COS. The diagnosis of phleboliths is primarily radiological, based on their intrinsic characteristics and their relationship with the vascular lesion. Generally, phleboliths appear as circular radiopacities, whereas sialoliths tend to have an elongated shape due to their location within the salivary duct( 10 ). Magnetic resonance (MR) imaging allows visualization of the dilated vessels characteristic of vascular malformations, enabling the assessment of LFVMs. Computed tomography (CT) excels in identifying calcified concretions, though it may not always clearly distinguish between vascular and salivary tissue. Doppler ultrasound is useful for detecting increased blood flow in vascular lesions, while sialography remains the most precise method for differentiating between these entities. Sialoliths appear as filling defects within the duct, whereas phleboliths are located outside the ductal system. However, conventional sialography is becoming obsolete, being replaced by MR sialography (MR-Si), which is a highly sensitive and specific imaging technique for assessing salivary duct pathology( 1 ). Therefore, for an accurate diagnosis, it is crucial to combine appropriate radiological evaluation with clinical findings. Based on this case, which involved two phleboliths within a submandibular LFVM, we aim to highlight the risk of misdiagnosis and the importance of MR-Si in the differential diagnosis between phlebolith and sialolith. Case presentation A 64-year-old female patient was referred for suspected right submandibular sialolithiasis, based on a prior non-contrast CT scan that revealed two calculi located in the ductal and hilar regions, with no associated lesions (Figs. 1 a and 1 b). The patient had experienced two episodes of floor-of-mouth inflammation over the past 10 years, initiating the diagnostic process after the most recent episode two years ago. Additionally, she reported a previous attempt at stone removal at another centre, under local anesthesia, which was discontinued due to profuse bleeding, preventing the identification and extraction of the calculi. On physical examination, the floor of the mouth was soft, and both calculi were easily palpable. The glandular parenchyma was not swollen, and the ductal papilla was patent and permeable. Following the protocol of our salivary gland unit, an MR-Si was requested prior to performing a scheduled sialendoscopy. The MR-Si showed that the major salivary glands maintained their normal morphology and signal, with no evidence of dilation of the excretory ducts or any relationship or impact of the calcified concretions on the salivary system (Fig. 2 a). Additionally, a T2-hyperintense lesion with small (< 5 mm) hypointense foci was identified, suggestive of phleboliths within a LFVM (Fig. 2 b). Given these findings, the scheduled sialendoscopy was cancelled, and a conservative approach was adopted. The patient remains asymptomatic to date. Discussion The confusion between phlebolith and sialolith is possible, frequent, and may lead to erroneous and potentially harmful decisions for patients. Therefore, diagnostic protocols must be established to enable their differential diagnosis. The literature has demonstrated that specific radiological features, such as the presence of hypointense areas within the lesion on T2-weighted MR sequences, are highly suggestive of a venous malformation( 11 ). In contrast, CT imaging can be misleading, failing to detect the presence of an LFVM and mistaking a phlebolith for a sialolith. This is particularly significant given that CT remains the standard diagnostic tool for salivary gland pathology in most centres. Additionally, sialendoscopy may serve as the gold standard for differential diagnosis by confirming, in situ , the absence of lithiasis in the ductal salivary system. However, with the advancement of MR, combining MR sequences with sialography protocol, the need for a minimally invasive procedure such as sialendoscopy may be reduced. MR-Si is now considered the optimal imaging modality before performing sialendoscopy, given its high sensitivity and specificity for detecting lithiasis, as well as its accuracy in identifying strictures( 1 ), which are the primary obstructive factors causing COS. MR-Si allows visualization of the ductal system, including its tertiary branches, and assessment of parenchymal tissue( 12 ), without requiring radiation or intravenous contrast. Consequently, it enables simultaneous evaluation of both the glandular parenchyma and the ductal system. Due to these advantages, MR-Si is a highly reliable diagnostic tool and should be implemented in dedicated salivary gland pathology units. The treatment of LFVMs depends on their size, location, and clinical manifestations. In cases of small and asymptomatic malformations, observation may be sufficient, whereas in cases of significant symptoms or progressive growth, sclerotherapy has shown favourable outcomes( 4 ). This case underscores the importance of a thorough patient history, a comprehensive physical examination, and the appropriate selection of complementary imaging tests. These steps enable the differentiation between sialolithiasis and other conditions affecting the salivary glands, the submandibular space, or the floor of the mouth. Although ductal obstruction was initially suspected, MR-Si facilitated the diagnosis of a vascular malformation, thereby avoiding an unnecessary invasive procedure—which had already been attempted at another centre under local anesthesia without success, posing significant haemorrhagic and life-threatening risks. Conclusion LFVMs can occur in the floor of the mouth and may contain phleboliths, mimicking sialoliths. The confusion between these entities can lead to erroneous and potentially harmful clinical decisions for patients. MR-Si is confirmed as the most appropriate imaging modality to distinguish between these two conditions and prevent unnecessary surgical procedures. Therefore, the implementation of MR-Si in salivary gland pathology units is essential. Abbreviations COS Chronic Obstructive Sialadenitis CT Computed Tomography LFVM Low-Flow Vascular Malformation MR Magnetic Resonance MR-Si MR Sialography Declarations Consent for publication : The patient provided explicit written consent for the publication of her clinical details and radiological images in this study. Funding: None Conflicts of interest : None Author Contribution All authors have made substantial contributions to the conception and design of the work, acquisition, analysis, and interpretation of data. All authors reviewed the final versión of manuscript. Acknowledgements: This case was presented as a poster communication at the 76th National Congress of the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC), held in Madrid, Spain, in October 2025. Data availability: Data sharing is not applicable to this article as no datasets were generated or analysed during the current study References Sánchez Barrueco Á, Santillán Coello JM, González Galán F, Alcalá Rueda I, Aly SO, Sobrino Guijarro B, et al. Epidemiologic, radiologic, and sialendoscopic aspects in chronic obstructive sialadenitis. Eur Arch Otorhinolaryngol. 2022;279(12):5813–20. de Temiño PR. Villar y Pérez de los Ríos F. Cálculos salivales [Salivary calculi]. Esp Odontoestomatol. 1948;7(8):661–73. Aynalı G, Unal F, Yarıktaş M, Yasan H, Ciriş M, Yılmaz O. Submandibular hemangioma with multiple phleboliths mimicking sialolithiasis: the first pediatric case. Kulak Burun Bogaz Ihtis Derg KBB J Ear Nose Throat. 2014;24(3):168–71. Moussa RM, Oseni AO, Patel S, Mailli L, Morgan R, Ratnam LA. Outcome evaluation for the treatment of low flow venous and lymphatic malformations. CVIR Endovasc. 2024;7(1):84. Bar T, Zagury A, London D, Shacham R, Nahlieli O. Calcifications simulating sialolithiasis of the major salivary glands. Dentomaxillofac Radiol. 2007;36(1):59–62. Ho C, Judson BL, Prasad ML. Vascular malformation with phleboliths involving the parotid gland: A case report with a review of the literature. Ear Nose Throat J. 2015;94(10–11):E1–5. Groppo ER, Glastonbury CM, Orloff LA, Kraus PE, Eisele DW. Vascular malformation masquerading as sialolithiasis and parotid obstruction: a case report and review of the literature. Laryngoscope. 2010;120(Suppl 4):S130. Chrysouli K, Karamagkiolas S. Venous malformation phleboliths mimicking submandibular sialadenitis in children. BMJ Case Rep. 2023;16(12):e257971. 10.1136/bcr-2023-257971 . Gooi Z, Mydlarz WK, Tunkel DE, Eisele DW. Submandibular venous malformation phleboliths mimicking sialolithiasis in children. Laryngoscope. 2014;124(12):2826–8. Su YX, Liao GQ, Wang L, Liang YJ, Chu M, Zheng GS. Sialoliths or phleboliths? Laryngoscope. 2009;119(7):1344–7. Eivazi B, Fasunla AJ, Güldner C, Masberg P, Werner JA, Teymoortash A. Phleboliths from venous malformations of the head and neck. Phlebology. 2013;28(2):86–92. Sobrino-Guijarro B, Cascarini L, Lingam RK. Advances in imaging of obstructed salivary glands can improve diagnostic outcomes. Oral Maxillofac Surg. 2013;17(1):11–9. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 14 Oct, 2025 Read the published version in BMC Oral Health → Version 1 posted Editorial decision: Revision requested 08 Aug, 2025 Reviews received at journal 28 Jul, 2025 Reviewers agreed at journal 28 Jul, 2025 Reviews received at journal 20 Jun, 2025 Reviewers agreed at journal 19 Jun, 2025 Reviews received at journal 27 May, 2025 Reviewers agreed at journal 13 May, 2025 Reviewers agreed at journal 11 May, 2025 Reviewers invited by journal 29 Apr, 2025 Editor assigned by journal 28 Apr, 2025 Editor invited by journal 28 Apr, 2025 Submission checks completed at journal 25 Apr, 2025 First submitted to journal 25 Apr, 2025 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6330727","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":449568919,"identity":"99232ddd-8863-41f4-ac78-287a58b08148","order_by":0,"name":"Alvaro Sánchez Barrueco","email":"data:image/png;base64,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","orcid":"","institution":"Alfonso X El Sabio University, Spain","correspondingAuthor":true,"prefix":"","firstName":"Alvaro","middleName":"Sánchez","lastName":"Barrueco","suffix":""},{"id":449568920,"identity":"e0b896f9-b32d-42e0-bef3-cc3e7ff17df3","order_by":1,"name":"Gonzalo Díaz Tapia","email":"","orcid":"","institution":"Alfonso X El Sabio University, Spain","correspondingAuthor":false,"prefix":"","firstName":"Gonzalo","middleName":"Díaz","lastName":"Tapia","suffix":""},{"id":449568925,"identity":"3f5653fe-3cc1-4376-9a40-692e85bd9b2b","order_by":2,"name":"Félix Guerra Gutiérrez","email":"","orcid":"","institution":"Hospital Universitario General de Villalba","correspondingAuthor":false,"prefix":"","firstName":"Félix","middleName":"Guerra","lastName":"Gutiérrez","suffix":""},{"id":449568926,"identity":"95dc85fe-bbff-4c5a-8c55-20561004f805","order_by":3,"name":"Elena Salvador Álvarez","email":"","orcid":"","institution":"Hospital Universitario 12 de Octubre","correspondingAuthor":false,"prefix":"","firstName":"Elena","middleName":"Salvador","lastName":"Álvarez","suffix":""},{"id":449568927,"identity":"5993e2f2-e6dd-44a7-99dd-cc2409f02fe7","order_by":4,"name":"José Miguel Villacampa Aubá","email":"","orcid":"","institution":"Hospital Universitario Fundación Jiménez Díaz","correspondingAuthor":false,"prefix":"","firstName":"José","middleName":"Miguel Villacampa","lastName":"Aubá","suffix":""}],"badges":[],"createdAt":"2025-03-28 20:53:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6330727/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6330727/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12903-025-06795-5","type":"published","date":"2025-10-14T15:57:05+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":82153966,"identity":"4430f758-115d-485c-8e57-247260663b2c","added_by":"auto","created_at":"2025-05-07 07:28:59","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":448777,"visible":true,"origin":"","legend":"\u003cp\u003eFigure 1. Non-contrast axial CT images reveal a sialolith (arrow) in the hilum of the submandibular gland (a) and another suspected lithiasis on the right side of the floor of the mouth, following the presumed course of Wharton’s duct (b). No retrograde dilatation of Wharton’s duct is observed.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6330727/v1/1ecf340f005bfa18b28eaf70.png"},{"id":82151507,"identity":"bddb19da-626d-45fe-b2e2-48655e02d1be","added_by":"auto","created_at":"2025-05-07 07:20:59","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":759369,"visible":true,"origin":"","legend":"\u003cp\u003eMR sialography image (a) and T2-weighted MR image (b) show an increased signal intensity lesion on the right side of the floor of the mouth (*), suggestive of a low-flow vascular malformation, containing two phleboliths (yellow arrows). The right submandibular gland is posteriorly displaced by the lesion (^). Note the normal appearance of Wharton’s duct on the left side (green arrow) and the absence of visualization of the duct on the right side.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6330727/v1/f82a3afb87859a969f0ec39b.png"},{"id":93955918,"identity":"9eff876a-1cb9-400b-8bbc-37ecde63be57","added_by":"auto","created_at":"2025-10-20 16:06:39","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2171920,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6330727/v1/190eb1a8-57dc-4833-8714-726173d932f4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The key role of magnetic resonance sialography in the differential diagnosis between sialolith and phlebolith of the floor of the mouth","fulltext":[{"header":"Background","content":"\u003cp\u003eSialolithiasis is one of the most common causes of chronic obstructive sialadenitis (COS)(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), which may present as recurrent inflammation of the salivary gland or be an incidental finding in imaging studies. Its prevalence in postmortem studies is estimated at 0.115%(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe presence of phleboliths in the head and neck region is well-documented in the literature(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e), predominantly in pediatric patients(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Previous reports have described head and neck lesions that may contain internal phleboliths, mimicking sialolithiasis, such as submandibular hemangioma(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) or low-flow vascular malformations (LFVM). LFVMs typically present as soft masses with a tendency toward inflammation or thrombosis(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e), with the potential to develop phleboliths. The inflammatory nature of LFVMs, sometimes exacerbated by meals, combined with imaging findings suggestive of sialolithiasis, often leads to a misdiagnosis of COS.\u003c/p\u003e \u003cp\u003eThe diagnosis of phleboliths is primarily radiological, based on their intrinsic characteristics and their relationship with the vascular lesion. Generally, phleboliths appear as circular radiopacities, whereas sialoliths tend to have an elongated shape due to their location within the salivary duct(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Magnetic resonance (MR) imaging allows visualization of the dilated vessels characteristic of vascular malformations, enabling the assessment of LFVMs. Computed tomography (CT) excels in identifying calcified concretions, though it may not always clearly distinguish between vascular and salivary tissue. Doppler ultrasound is useful for detecting increased blood flow in vascular lesions, while sialography remains the most precise method for differentiating between these entities. Sialoliths appear as filling defects within the duct, whereas phleboliths are located outside the ductal system. However, conventional sialography is becoming obsolete, being replaced by MR sialography (MR-Si), which is a highly sensitive and specific imaging technique for assessing salivary duct pathology(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Therefore, for an accurate diagnosis, it is crucial to combine appropriate radiological evaluation with clinical findings.\u003c/p\u003e \u003cp\u003eBased on this case, which involved two phleboliths within a submandibular LFVM, we aim to highlight the risk of misdiagnosis and the importance of MR-Si in the differential diagnosis between phlebolith and sialolith.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA 64-year-old female patient was referred for suspected right submandibular sialolithiasis, based on a prior non-contrast CT scan that revealed two calculi located in the ductal and hilar regions, with no associated lesions (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ea and \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eb). The patient had experienced two episodes of floor-of-mouth inflammation over the past 10 years, initiating the diagnostic process after the most recent episode two years ago. Additionally, she reported a previous attempt at stone removal at another centre, under local anesthesia, which was discontinued due to profuse bleeding, preventing the identification and extraction of the calculi.\u003c/p\u003e\n\u003cp\u003eOn physical examination, the floor of the mouth was soft, and both calculi were easily palpable. The glandular parenchyma was not swollen, and the ductal papilla was patent and permeable. Following the protocol of our salivary gland unit, an MR-Si was requested prior to performing a scheduled sialendoscopy. The MR-Si showed that the major salivary glands maintained their normal morphology and signal, with no evidence of dilation of the excretory ducts or any relationship or impact of the calcified concretions on the salivary system (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ea). Additionally, a T2-hyperintense lesion with small (\u0026lt;\u0026thinsp;5 mm) hypointense foci was identified, suggestive of phleboliths within a LFVM (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb).\u003c/p\u003e\n\u003cp\u003eGiven these findings, the scheduled sialendoscopy was cancelled, and a conservative approach was adopted. The patient remains asymptomatic to date.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe confusion between phlebolith and sialolith is possible, frequent, and may lead to erroneous and potentially harmful decisions for patients. Therefore, diagnostic protocols must be established to enable their differential diagnosis.\u003c/p\u003e \u003cp\u003eThe literature has demonstrated that specific radiological features, such as the presence of hypointense areas within the lesion on T2-weighted MR sequences, are highly suggestive of a venous malformation(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). In contrast, CT imaging can be misleading, failing to detect the presence of an LFVM and mistaking a phlebolith for a sialolith. This is particularly significant given that CT remains the standard diagnostic tool for salivary gland pathology in most centres.\u003c/p\u003e \u003cp\u003eAdditionally, sialendoscopy may serve as the gold standard for differential diagnosis by confirming, \u003cem\u003ein situ\u003c/em\u003e, the absence of lithiasis in the ductal salivary system. However, with the advancement of MR, combining MR sequences with sialography protocol, the need for a minimally invasive procedure such as sialendoscopy may be reduced. MR-Si is now considered the optimal imaging modality before performing sialendoscopy, given its high sensitivity and specificity for detecting lithiasis, as well as its accuracy in identifying strictures(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), which are the primary obstructive factors causing COS. MR-Si allows visualization of the ductal system, including its tertiary branches, and assessment of parenchymal tissue(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e), without requiring radiation or intravenous contrast. Consequently, it enables simultaneous evaluation of both the glandular parenchyma and the ductal system. Due to these advantages, MR-Si is a highly reliable diagnostic tool and should be implemented in dedicated salivary gland pathology units.\u003c/p\u003e \u003cp\u003eThe treatment of LFVMs depends on their size, location, and clinical manifestations. In cases of small and asymptomatic malformations, observation may be sufficient, whereas in cases of significant symptoms or progressive growth, sclerotherapy has shown favourable outcomes(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis case underscores the importance of a thorough patient history, a comprehensive physical examination, and the appropriate selection of complementary imaging tests. These steps enable the differentiation between sialolithiasis and other conditions affecting the salivary glands, the submandibular space, or the floor of the mouth. Although ductal obstruction was initially suspected, MR-Si facilitated the diagnosis of a vascular malformation, thereby avoiding an unnecessary invasive procedure\u0026mdash;which had already been attempted at another centre under local anesthesia without success, posing significant haemorrhagic and life-threatening risks.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eLFVMs can occur in the floor of the mouth and may contain phleboliths, mimicking sialoliths. The confusion between these entities can lead to erroneous and potentially harmful clinical decisions for patients.\u003c/p\u003e \u003cp\u003eMR-Si is confirmed as the most appropriate imaging modality to distinguish between these two conditions and prevent unnecessary surgical procedures. Therefore, the implementation of MR-Si in salivary gland pathology units is essential.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCOS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eChronic Obstructive Sialadenitis\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\"\u003eLFVM\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLow-Flow Vascular Malformation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic Resonance\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMR-Si\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMR Sialography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003e \u003cb\u003eConsent for publication\u003c/b\u003e:\u003c/strong\u003e \u003cp\u003eThe patient provided explicit written consent for the publication of her clinical details and radiological images in this study.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eNone\u003c/p\u003e \u003cp\u003e \u003cb\u003eConflicts of interest\u003c/b\u003e: None\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAll authors have made substantial contributions to the conception and design of the work, acquisition, analysis, and interpretation of data. All authors reviewed the final versi\u0026oacute;n of manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements:\u003c/h2\u003e \u003cp\u003eThis case was presented as a poster communication at the 76th National Congress of the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC), held in Madrid, Spain, in October 2025.\u003c/p\u003e\u003ch2\u003eData availability:\u003c/h2\u003e \u003cp\u003eData sharing is not applicable to this article as no datasets were generated or analysed during the current study\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eS\u0026aacute;nchez Barrueco \u0026Aacute;, Santill\u0026aacute;n Coello JM, Gonz\u0026aacute;lez Gal\u0026aacute;n F, Alcal\u0026aacute; Rueda I, Aly SO, Sobrino Guijarro B, et al. Epidemiologic, radiologic, and sialendoscopic aspects in chronic obstructive sialadenitis. Eur Arch Otorhinolaryngol. 2022;279(12):5813\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ede Temi\u0026ntilde;o PR. Villar y P\u0026eacute;rez de los R\u0026iacute;os F. C\u0026aacute;lculos salivales [Salivary calculi]. Esp Odontoestomatol. 1948;7(8):661\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAynalı G, Unal F, Yarıktaş M, Yasan H, Ciriş M, Yılmaz O. Submandibular hemangioma with multiple phleboliths mimicking sialolithiasis: the first pediatric case. Kulak Burun Bogaz Ihtis Derg KBB J Ear Nose Throat. 2014;24(3):168\u0026ndash;71.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoussa RM, Oseni AO, Patel S, Mailli L, Morgan R, Ratnam LA. Outcome evaluation for the treatment of low flow venous and lymphatic malformations. CVIR Endovasc. 2024;7(1):84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBar T, Zagury A, London D, Shacham R, Nahlieli O. Calcifications simulating sialolithiasis of the major salivary glands. Dentomaxillofac Radiol. 2007;36(1):59\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHo C, Judson BL, Prasad ML. Vascular malformation with phleboliths involving the parotid gland: A case report with a review of the literature. Ear Nose Throat J. 2015;94(10\u0026ndash;11):E1\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGroppo ER, Glastonbury CM, Orloff LA, Kraus PE, Eisele DW. Vascular malformation masquerading as sialolithiasis and parotid obstruction: a case report and review of the literature. Laryngoscope. 2010;120(Suppl 4):S130.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChrysouli K, Karamagkiolas S. Venous malformation phleboliths mimicking submandibular sialadenitis in children. BMJ Case Rep. 2023;16(12):e257971. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1136/bcr-2023-257971\u003c/span\u003e\u003cspan address=\"10.1136/bcr-2023-257971\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGooi Z, Mydlarz WK, Tunkel DE, Eisele DW. Submandibular venous malformation phleboliths mimicking sialolithiasis in children. Laryngoscope. 2014;124(12):2826\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSu YX, Liao GQ, Wang L, Liang YJ, Chu M, Zheng GS. Sialoliths or phleboliths? Laryngoscope. 2009;119(7):1344\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEivazi B, Fasunla AJ, G\u0026uuml;ldner C, Masberg P, Werner JA, Teymoortash A. Phleboliths from venous malformations of the head and neck. Phlebology. 2013;28(2):86\u0026ndash;92.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSobrino-Guijarro B, Cascarini L, Lingam RK. Advances in imaging of obstructed salivary glands can improve diagnostic outcomes. Oral Maxillofac Surg. 2013;17(1):11\u0026ndash;9.\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-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Sialolith, Sialolithiasis, Phlebolith, floor of the mouth, magnetic resonance sialography, low-flow vascular malformation, sialendoscopy, sialadenitis","lastPublishedDoi":"10.21203/rs.3.rs-6330727/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6330727/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e The confusion between a phlebolith and a sialolith in the floor of the mouth can pose serious surgical risks, making it essential to define appropriate complementary imaging studies.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase presentation:\u003c/strong\u003e We present the case of a patient with right submandibular sialolithiasis suspected by computed tomography. A previous attempt at extraction in another centre, under local anesthesia, was interrupted due to profuse bleeding, preventing the localization and removal of the calculi. Due to our pre-surgical study protocol using magnetic resonance sialography (MR-Si), a low-flow vascular malformation with internal phleboliths was revealed, without involvement of the salivary duct. As a result, the planned sialendoscopy was cancelled, and a follow-up approach was chosen given the asymptomatic nature of the condition.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e This case underscores the importance of standardizing radiological studies for salivary gland and floor-of-mouth pathology, highlighting MR-Si for its high sensitivity and specificity. Therefore, MR-Si enables more precise surgical planning and helps prevent unnecessary intraoperative complications.\u003c/p\u003e","manuscriptTitle":"The key role of magnetic resonance sialography in the differential diagnosis between sialolith and phlebolith of the floor of the mouth","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-07 07:20:54","doi":"10.21203/rs.3.rs-6330727/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-08T06:06:20+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-28T06:21:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"282843473628458266271509258326224863468","date":"2025-07-28T06:12:56+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-20T16:43:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"335418704492166910084736376743997143471","date":"2025-06-19T12:04:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-27T07:33:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"256819365227535718481819376317961711143","date":"2025-05-13T05:21:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"298266887283022100326369286169369670084","date":"2025-05-12T01:35:39+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-29T08:46:02+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-28T18:33:37+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-04-28T17:55:14+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-25T14:04:05+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2025-04-25T14:02:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"efa226c3-3c92-47ef-928a-5f3adfcebad5","owner":[],"postedDate":"May 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-10-20T15:59:45+00:00","versionOfRecord":{"articleIdentity":"rs-6330727","link":"https://doi.org/10.1186/s12903-025-06795-5","journal":{"identity":"bmc-oral-health","isVorOnly":false,"title":"BMC Oral Health"},"publishedOn":"2025-10-14 15:57:05","publishedOnDateReadable":"October 14th, 2025"},"versionCreatedAt":"2025-05-07 07:20:54","video":"","vorDoi":"10.1186/s12903-025-06795-5","vorDoiUrl":"https://doi.org/10.1186/s12903-025-06795-5","workflowStages":[]},"version":"v1","identity":"rs-6330727","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6330727","identity":"rs-6330727","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}