Intramuscular cavernous haemangioma of the temporal muscle presenting with bone erosion and atypical radiological features

Intramuscular cavernous haemangioma of the temporal muscle presenting with bone erosion and atypical radiological features | 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 Intramuscular cavernous haemangioma of the temporal muscle presenting with bone erosion and atypical radiological features Mohamed Chehbouni, Mohammed Rami, Ismail El Boussouni, Omar Oulghoul, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8928137/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Background Intramuscular cavernous haemangiomas are rare benign vascular tumours, particularly when arising in the temporalis muscle or infratemporal fossa. Radiological diagnosis is challenging because imaging features often overlap with those of other benign soft-tissue lesions, and bone involvement is considered unusual. To our knowledge, bone erosion associated with temporalis intramuscular cavernous haemangioma has been rarely described in the literature. Case presentation : We report the case of a 37-year-old woman with a slowly progressive left temporo-infratemporal mass evolving over 12 years and repeatedly diagnosed as a lipoma. Cross-sectional imaging revealed a deeply located, highly vascularised intramuscular lesion with atypical radiological features, notably erosion of the adjacent temporal bone and the greater wing of the sphenoid. Magnetic resonance imaging demonstrated a heterogeneous mass, hypointense on T1-weighted sequences and markedly hyperintense on T2-weighted sequences, with intense heterogeneous enhancement following gadolinium administration. Because of the apparent aggressive imaging behaviour, malignant or invasive lipomatous tumours were initially suspected. Surgical management consisted of maximal safe excision via an infratemporal approach, leaving a small deep residual component due to excessive vascularity. Histopathological examination confirmed a cavernous intramuscular haemangioma. Post-operative follow-up MRI demonstrated a small, stable residual lesion without progression. Conclusion This case emphasises the importance of radiological evaluation in intramuscular haemangiomas occurring at rare locations. Although cavernous haemangiomas are classically non-invasive, associated bone erosion may occur and represent a diagnostic pitfall, potentially mimicking aggressive neoplastic processes. Awareness of this atypical imaging presentation can help avoid misdiagnosis and guide appropriate surgical management. Intramuscular haemangioma Cavernous haemangioma Temporalis muscle Bone erosion Magnetic resonance imaging Diagnostic pitfall Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Introduction Haemangiomas are benign vascular lesions that may arise in various tissues, most commonly involving the skin and subcutaneous planes of the head and neck region [ 1 ]. Intramuscular haemangiomas (IMHs) are uncommon, accounting for less than 1% of all haemangiomas, and are rarely encountered in the head and neck [ 2 ]. Among the different histological subtypes, cavernous haemangiomas—characterised by large, dilated vascular channels—represent the most frequently reported variant [ 3 ]. These lesions predominantly involve the masseter and trapezius muscles, whereas localisation within the temporalis muscle or extension into the infratemporal fossa remains exceptional [ 4 , 5 ]. The clinical and radiological presentation of cavernous haemangiomas in these deep locations is often non-specific, contributing to frequent diagnostic errors. Patients typically present with a slowly enlarging, painless mass, without associated cutaneous discolouration, bruit, or pulsatility [ 2 ]. As a result, these lesions are frequently misinterpreted as more common soft-tissue tumours, including lipomas, schwannomas, neurofibromas, or other vascular malformations [ 6 , 7 ]. Imaging plays a central role in the diagnostic work-up, with magnetic resonance imaging (MRI) considered the modality of choice. Classically, cavernous haemangiomas demonstrate hypointense signal on T1-weighted sequences and marked hyperintensity on T2-weighted images, with heterogeneous enhancement following gadolinium administration [ 8 ]. However, these radiological features are not pathognomonic and may overlap with other benign or locally aggressive entities. Moreover, fine-needle aspiration or biopsy frequently yields inconclusive results because of the vascular nature of the lesion [ 9 ]. Given their rarity, deep location, and diagnostic ambiguity, cavernous haemangiomas of the temporalis muscle and infratemporal fossa represent a particular challenge for both radiologists and surgeons. Complete surgical excision remains the treatment of choice, allowing definitive histological diagnosis and reducing the risk of recurrence [10,11]. We report a rare case of a cavernous haemangioma involving the temporo-infratemporal region, initially misdiagnosed as a lipoma, in which imaging revealed atypical features that complicated the pre-operative diagnosis and significantly influenced surgical decision-making. Case Presentation We report the case of a 37-year-old woman with no relevant medical history who presented with a progressively enlarging left temporo-infratemporal mass. The swelling had been slowly evolving over approximately twelve years. She underwent surgical excision of the lesion in 2019 in a plastic surgery department, with histopathological analysis at that time consistent with a lipoma. However, the mass recurred within one year. Head and neck examination revealed a firm, non-pulsatile, non-tender left temporofacial swelling, fixed to both superficial and deep planes, without inflammatory changes or fistulisation of the overlying skin (Fig. 1 ). No cervical lymphadenopathy was detected. Cranial nerve examination was normal; in particular, there was no peripheral facial palsy and no sensory or motor deficits were observed. Otoscopic, nasal, oral cavity, and laryngoscopic examinations were unremarkable. Radiological evaluation over time demonstrated persistence of the left temporo-infratemporal lesion. The initial CT scan performed in 2017 showed a heterogeneous enlargement of the left temporalis muscle with adjacent fat infiltration, without evidence of bone involvement, initially suggesting an inflammatory process. In 2019, a follow-up CT scan revealed a well-defined infratemporal mass measuring 48 × 33 × 23 mm, extending towards the zygomatic arch and abutting the lateral pterygoid and masseter muscles, with associated bone lysis of the greater wing of the sphenoid. Following surgical excision in the same year, a CT scan performed in May 2024 demonstrated recurrence of the lesion, measuring 33 × 25 × 26 mm, with extension into the adjacent soft tissues, yet without overtly aggressive radiological features (Fig. 2 ). Magnetic resonance imaging performed in December 2024 demonstrated a soft-tissue mass in the left temporo-infratemporal region measuring 60 × 47 × 22 mm, hypointense on T1-weighted sequences and hyperintense on T2-weighted sequences, with heterogeneous gadolinium enhancement. The lesion infiltrated the muscular plane, displaced the overlying cutaneous plane, and extended medially into the masticator space and laterally towards the masseter muscle, without evidence of cerebral or skull base invasion. Follow-up MRI in May 2025 showed further enlargement of the lesion, measuring 63 × 49 × 59 mm, now associated with bone lysis of the temporal bone and extension into the temporal fossa. These imaging features raised concern for an aggressive lipomatous tumour, such as an angiolipoma (Fig. 3 ) Histopathological findings were consistent across multiple samplings. In February 2019, analysis revealed a lobulated adipose proliferation composed of mature adipocytes separated by thin fibromuscular septa, without evidence of malignancy, consistent with a benign lipoma. A subsequent biopsy in April 2019 confirmed an intramuscular lipoma, characterised by mature adipose tissue with thickened fibrous septa and regular striated muscle fibres, again without features of malignancy. In May 2025, the patient underwent a further biopsy under general anaesthesia through a direct incision over the left temporal region. Following subcutaneous and muscular dissection with elevation of the flaps, a reddish submuscular mass was identified beneath the temporalis muscle. Multiple biopsies were obtained for histopathological analysis, which again confirmed a benign lipomatous lesion without evidence of malignancy A second intervention was performed in July 2025 for definitive management (Figs. 4 and 5 ). The procedure began with a Redon incision, allowing identification of the main trunk of the facial nerve within the parotid gland, followed by meticulous dissection and preservation of its branches, particularly the frontal and superior palpebral branches, to avoid injury during the temporal stage of the approach. The incision was then extended superiorly, curving around the insertions of the temporalis muscle at the temporal fossa and into the scalp. After elevation of the skin flap and dissection of the temporalis muscle, a venous-appearing vascular tumour was identified within the muscle fibres. The lesion retracted on compression and was confined to the thickness of the temporalis muscle. Inspection of the infratemporal fossa revealed no additional lesions The tumour was surgically approached and excised to the maximal safe extent. Intraoperatively, it appeared as a highly vascularised intramuscular mass involving the temporalis muscle, without extension to adjacent neurovascular structures. Owing to its marked vascular nature and the risk of excessive bleeding, complete macroscopic excision was not pursued, and a small residual component was deliberately left in situ to ensure surgical safety. Adequate haemostasis was achieved, and the temporal muscle was reconstructed by intramuscular suturing of the resected portion and reattachment to its original insertion. A suction drain was placed and subsequently removed without complication. The postoperative course was uneventful. Histopathological examination of the excised specimen demonstrated features consistent with a cavernous haemangioma, characterised by dilated vascular channels lined by flattened endothelium, without cytological atypia or evidence of malignant transformation. The analysed surgical margins were free of tumour (Fig. 8 ). Early postoperative follow-up showed satisfactory wound healing with no immediate complications. At two months, clinical examination revealed a well-healed surgical site and no clinically detectable residual mass or recurrence (Fig. 6 ). Follow-up magnetic resonance imaging performed at the same interval demonstrated a small, stable residual lesion within the temporalis muscle, without interval growth or pathological enhancement. These findings indicate effective surgical debulking with radiological stabilisation of the residual component and confirm a favourable short-term outcome (Fig. 7 ) . A summary of the chronological clinical course, diagnostic evaluations, and therapeutic interventions is presented in Table 1 . Table 1 Chronological timeline of clinical presentation, diagnostic investigations, surgical interventions, and follow-up Year Event 2017 Initial CT scan 2019 Surgical excision (lipoma diagnosis) 2024 Recurrence on imaging July 2025 Definitive surgery September 2025 Stable residual lesion Discussion Intramuscular haemangiomas (IMHs) are uncommon benign vascular tumours arising from skeletal muscle, accounting for less than 1% of all haemangiomas [ 1 ]. They predominantly affect the trunk and extremities, whereas involvement of the head and neck region is rare, representing approximately 10–15% of reported cases [ 2 , 4 ]. Within this anatomical area, the masseter and trapezius muscles are most frequently involved, while localisation within the temporalis muscle remains exceptional, with only a limited number of cases documented in the literature [ 2 , 4 , 10 ]. From a histopathological standpoint, intramuscular haemangiomas are classically classified into capillary, cavernous, and mixed subtypes [ 1 ]. Capillary haemangiomas consist of densely packed small-calibre vascular channels and represent the most common subtype overall. In contrast, cavernous haemangiomas are characterised by large, dilated blood-filled vascular spaces separated by fibrous septa [ 4 , 10 ]. Mixed lesions exhibit features of both patterns. Notably, although capillary haemangiomas predominate among IMHs in general, cavernous haemangiomas appear to be disproportionately represented in reported cases involving the temporalis muscle [ 2 , 10 ]. The histopathological findings in our case were consistent with a cavernous intramuscular haemangioma. Clinically, intramuscular cavernous haemangiomas typically present as a slowly enlarging, well-circumscribed intramuscular mass with indolent growth. Lesions may remain asymptomatic for prolonged periods [ 1 , 4 ]. Pain has been reported in approximately 30–60% of cases and is often related to muscle contraction or physical activity, whereas many patients present with a painless swelling [ 2 , 5 ]. Cutaneous changes, pulsation, or audible bruit are usually absent, which helps distinguish these lesions from high-flow vascular malformations [ 5 ]. The mass is generally mobile relative to the overlying skin and does not demonstrate overt invasion of adjacent structures on clinical examination. Because of this nonspecific clinical presentation, intramuscular haemangiomas are frequently misdiagnosed prior to surgery. Lipoma represents the most common initial diagnosis, followed by other benign soft-tissue tumours, cystic lesions, inflammatory processes, or, less commonly, malignant neoplasms [ 4 , 10 ]. In the temporal region, the differential diagnosis also includes dermoid cysts, sebaceous cysts, temporal arteritis, and soft-tissue sarcomas. Owing to the absence of pathognomonic clinical signs, accurate preoperative diagnosis has been reported in fewer than 10% of cases [ 2 , 5 ]. In our patient, the lesion was initially interpreted as an intramuscular lipoma on biopsy, further illustrating the diagnostic challenge associated with these tumours. Imaging therefore plays a pivotal role in the evaluation of intramuscular haemangiomas. Magnetic resonance imaging (MRI) is considered the modality of choice, typically demonstrating a lesion that is isointense or hypointense relative to muscle on T1-weighted sequences and markedly hyperintense on T2-weighted images, reflecting high fluid content and slow venous flow [ 7 , 9 ]. Following gadolinium administration, strong and often heterogeneous enhancement is commonly observed. Computed tomography (CT) may reveal internal calcifications corresponding to phleboliths, which are present in approximately 15–25% of intramuscular haemangiomas and are regarded as a suggestive imaging feature [ 6 , 7 ]. Importantly, most reported cases of temporalis muscle haemangiomas do not demonstrate adjacent bone involvement [ 4 , 10 ]. In contrast, our patient exhibited apparent erosion of the adjacent temporal bone, an atypical radiological finding that significantly complicated the diagnostic process and initially raised concern for a more aggressive or infiltrative lesion. This unusual imaging feature represents the principal radiological interest of the present case and highlights the potential for cavernous haemangiomas to mimic malignant soft-tissue tumours on cross-sectional imaging. Although angiography is not routinely required, it may be useful in selected cases to delineate feeding vessels or exclude high-flow vascular malformations [ 5 ]. However, many intramuscular cavernous haemangiomas exhibit slow-flow characteristics and lack a distinct arterial blush, thereby limiting the diagnostic yield of conventional angiography. Definitive diagnosis relies on histopathological examination. Cavernous haemangiomas are composed of large, blood-filled vascular spaces lined by flattened endothelium and separated by fibrous stroma, with surrounding skeletal muscle fibres typically displaced rather than infiltrated [ 1 , 10 ]. These features were clearly identified in our specimen, confirming the benign nature of the lesion. Malignant transformation has not been reported in temporalis muscle haemangiomas, and no cases in the literature have demonstrated cytological atypia or invasive behaviour [ 2 , 4 ]. Management strategies depend on symptomatology, lesion size, anatomical location, growth behaviour, and cosmetic considerations. Observation may be appropriate for small, asymptomatic, and stable lesions, particularly when cosmetic impact is minimal [ 5 , 8 ]. Nevertheless, most reported temporalis muscle haemangiomas have been managed surgically, often because of diagnostic uncertainty or progressive enlargement [ 7 , 10 ]. Complete surgical excision with a margin of normal muscle is generally advocated when feasible, as it provides definitive diagnosis and excellent local control. However, several authors have emphasised that in deeply seated or highly vascular lesions, particularly those located near critical structures, subtotal excision may represent a reasonable therapeutic compromise in order to minimise operative morbidity, provided that residual disease remains stable and is closely monitored [ 5 , 7 , 6 ]. In such cases, maximal safe resection rather than radical excision is considered acceptable. In our patient, complete excision was limited by the deep location and pronounced vascularity of the tumour, necessitating intentional preservation of a small residual component within the deeper temporal fossa. Postoperative MRI confirmed the presence of a small, stable residual lesion without clinical correlate. Similar conservative surgical approaches have been reported, with favourable outcomes and no evidence of progression during follow-up [ 6 , 8 ]. Surgical complications are uncommon but may include injury to the temporal branch of the facial nerve. Transient postoperative eyebrow weakness has been described, typically resolving spontaneously within weeks to months [ 3 ]. Careful surgical technique and detailed anatomical knowledge are therefore essential. Overall, the prognosis of temporalis muscle cavernous haemangiomas is excellent. Recurrence is primarily associated with incomplete excision and appears to be more frequent in capillary subtypes, whereas cavernous haemangiomas demonstrate lower recurrence rates [ 1 , 6 ]. Importantly, even in cases of subtotal excision, stable residual disease without progression has been reported, supporting the role of long-term clinical and radiological surveillance as an acceptable management strategy when complete resection is not feasible [ 6 , 7 ]. Conclusion Cavernous haemangiomas of the temporalis muscle and infratemporal fossa remain exceedingly rare entities that pose significant diagnostic challenges. Their nonspecific clinical presentation and overlapping radiological features frequently lead to misdiagnosis, as exemplified in our case where bone erosion suggested an angiolipoma or more aggressive lesion. Careful interpretation of imaging studies, combined with a high index of suspicion, is therefore essential when evaluating atypical temporal or infratemporal masses. Histopathological examination remains the gold standard for definitive diagnosis, while complete surgical excision continues to be the treatment of choice, both for diagnostic confirmation and for curative intent. With meticulous surgical planning, including preservation of critical neurovascular structures, outcomes are excellent and recurrence is rare when resection is complete. This case highlights the importance of considering vascular tumors, including cavernous haemangiomas, in the differential diagnosis of temporalis and infratemporal lesions, even when unusual features such as apparent bone erosion are present. Reporting such rare cases adds valuable insight to the limited body of literature and contributes to improved awareness, diagnosis, and management strategies for future patients. Declarations Ethics approval and consent to participate The requirement of ethical approval for this study was waived by the Ethics Committee of the Faculty of Medicine and Pharmacy of Marrakech affiliated with Mohammed VI University Hospital in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained from the patient for participation in the study and for publication of clinical data and images. Consent for publication Written informed consent was obtained from the patient for publication of the clinical details and accompanying images. Availability of data and materials All data generated or analysed during this study are included in this published article. Additional information is available from the corresponding author upon reasonable request. Competing interests The authors declare that they have no competing interests. Funding The authors received no specific financial support for the research, authorship, or publication of this article. Clinical trial number not applicable. Authors’ contributions MR: Conceptualisation, surgical management, manuscript drafting. MC: Data collection and literature review. SY: Radiological analysis and interpretation. OO: Intraoperative assistance and data acquisition. YL: Postoperative follow-up and manuscript revision. YR: Supervision and critical revision of the manuscript. AR: Senior supervision, validation of surgical strategy, and final approval of the manuscript. All authors read and approved the final manuscript. Acknowledgements The authors and the Department of Otolaryngology – Head and Neck Surgery would like to thank Dr. Mohammed Rami for the hand-drawn illustration presented in Fig. 4, depicting the key surgical steps of the infratemporal approach. 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Ocular adnexal intramuscular haemangioma arising from the eyelid: case report and literature review. Orbit . 2023;42(3):290–294. Liu D, Bao Y, Wang Y, Lu X, Shen J, Huang S, et al. Case report: intercostal intramuscular haemangioma with sternal invasion. Front Oncol . 2024;14:1360626. https://doi.org/10.3389/fonc.2024.1360626 Orly J, Bisdorff A, Joly A, Edee AE, Tavernier E, Herbreteau D, et al. Characteristics, natural course and treatment of intramuscular capillary-type haemangioma: a systematic literature review. Acta Derm Venereol . 2023;103:adv00893. https://doi.org/10.2340/actadv.v103.4432 Feger J, Ranchod A, Campos A, et al. Intramuscular haemangiomas. Radiopaedia.org [Internet]. 2024 [cited 2026 Feb 20]. Available from: https://radiopaedia.org/articles/intramuscular-haemangiomas Joud B, Beqqali B, Loubaris S, El Beyeg M, Zamani O, Kaoutar Z, et al. Exceptional localization of intramuscular haemangioma: insights from a case report. Radiol Case Rep . 2025. Epub ahead of print. Murakami K, Shinohara T, Saito K, Hoshino T. Intramuscular haemangioma of the temporalis muscle. J Oral Maxillofac Surg . 1991;49(9):1008–1012. Allen PW, Enzinger FM. Haemangioma of skeletal muscle. Cancer . 1972;29(1):8–22. Additional Declarations No competing interests reported. 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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-8928137","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":617329507,"identity":"6b4038aa-5130-4d00-a011-e97ee6d80167","order_by":0,"name":"Mohamed Chehbouni","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"","lastName":"Chehbouni","suffix":""},{"id":617329509,"identity":"89d6ac16-74b5-4194-8539-1818f304f6b7","order_by":1,"name":"Mohammed Rami","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYDCCA2BSAoiZGx8ASR4+ErQwNhuAtLARqQUEGNtAGhkIauG7fYDtw88cCwZ+6YNtlV9z7GTYGJgfPrqBR4vkuQTmmb3bJBgk+xLbbstuSwY6jM3YOAePFoMzDMwMvEAtBmcY225LbmMGauFhkyakhfEvVEux5LZ64rQww2xh/LjtMGEtkmcYm5llt0nwSPYwNkszbjvOw8ZMwC98Z5gPM77dVifHz8N88OPPbdX2/OzNDx/j0wKMjgYQyQMimCEkXuXoun+QonoUjIJRMApGDAAAs9w9FzneiVUAAAAASUVORK5CYII=","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":true,"prefix":"","firstName":"Mohammed","middleName":"","lastName":"Rami","suffix":""},{"id":617329510,"identity":"69b49c3e-04e7-47e4-8363-eaf779d80bb2","order_by":2,"name":"Ismail El Boussouni","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Ismail","middleName":"El","lastName":"Boussouni","suffix":""},{"id":617329512,"identity":"b1c12cee-0ee7-495f-a3fd-6d56ea1f8bed","order_by":3,"name":"Omar Oulghoul","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Omar","middleName":"","lastName":"Oulghoul","suffix":""},{"id":617329513,"identity":"91a0ce0a-e76e-4947-9e99-264d38ef1d7d","order_by":4,"name":"Youssef Lakhdar","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Youssef","middleName":"","lastName":"Lakhdar","suffix":""},{"id":617329515,"identity":"76adc056-8973-4913-bdb0-b56b4fe3245d","order_by":5,"name":"Youssef Rochdi","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Youssef","middleName":"","lastName":"Rochdi","suffix":""},{"id":617329518,"identity":"5a3e5a06-2d9a-43fb-92ea-d6fcd2b3cce5","order_by":6,"name":"Abdelaziz Raji","email":"","orcid":"","institution":"Mohammed VI University Hospital Center","correspondingAuthor":false,"prefix":"","firstName":"Abdelaziz","middleName":"","lastName":"Raji","suffix":""}],"badges":[],"createdAt":"2026-02-20 17:38:30","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8928137/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8928137/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106402522,"identity":"e0056a29-0cdc-46fb-a9e1-8a36d5cf6fbc","added_by":"auto","created_at":"2026-04-08 09:12:13","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":50146,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePreoperative clinical photograph of the patient showing a visible swelling in the left temporal and infratemporal regions, producing a noticeable facial asymmetry. The mass appears as a firm, rounded contour beneath intact skin without discoloration or inflammatory changes\u003c/em\u003e\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/59e6f55c23969604eb4f035a.jpg"},{"id":106214753,"identity":"5a569ef3-c8b4-4d45-b2ab-4664a2ebaa0b","added_by":"auto","created_at":"2026-04-06 08:16:49","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":81097,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eCT scan of the head and face demonstrating the left temporo-infratemporal lesion (white arrows).\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(A)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Axial section at the level of the infratemporal fossa showing a well-defined soft-tissue mass within the left temporal region, extending inferiorly towards the infratemporal fossa. No intravenous contrast was administered. Associated bone lysis of the greater wing of the sphenoid is observed.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(B)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Coronal section through the same region following intravenous contrast administration, demonstrating marked enhancement of the lesion, consistent with a vascularised tumour, and delineating its extension towards the deep facial planes\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/8ecd379b75085294ef6cc7f5.jpg"},{"id":106214746,"identity":"530f37ff-2978-4de0-b959-b0c6a5f2711c","added_by":"auto","created_at":"2026-04-06 08:16:48","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":96218,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eMagnetic resonance imaging of the head demonstrating the left temporo-infratemporal lesion (white arrows).\u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(A)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003eAxial T1-weighted sequence showing a well-defined, heterogeneous isointense mass within the left temporalis muscle, with intralesional flow voids indicating prominent vascular structures. \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(B)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Axial T1-weighted post-gadolinium sequence at the same level, demonstrating intense heterogeneous enhancement consistent with a vascular lesion; note the suspected erosion of the temporal bone (black arrow).\u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(C)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Axial T2-weighted \u0026nbsp;sequence showing a hyperintense mass infiltrating the temporalis muscle, displacing the overlying cutaneous plane, and extending medially into the masticator space and laterally towards the masseter muscle. \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(D)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Coronal T2-weighted sequence confirming a hyperintense lesion with superior extension into the temporal fossa and inferior extension into the infratemporal region, without evidence of intracranial or skull base invasion\u003c/em\u003e\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/3962de956cc79f747cf19990.jpg"},{"id":106403310,"identity":"910c7dc9-269d-4f22-bba2-111bffdcf250","added_by":"auto","created_at":"2026-04-08 09:14:03","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":108296,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eSteps of the infratemporal approach used during the second intervention (Authors’ creation).\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003eA:\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Marking of the Redon incision, extended superiorly into the scalp (dotted line). The patient is positioned supine with the head turned towards the contralateral side.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003eB:\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Identification of the main trunk of the facial nerve and its frontal and palpebral branches, followed by elevation of the flap over the temporal region, exposing the temporalis muscle.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003eC:\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Incision and detachment of the temporalis muscle with subperiosteal dissection from the temporal squama, allowing access to the infratemporal fossa beneath the temporalis muscle (black arrow)\u003c/em\u003e\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/a810c1744dcce52623e20130.jpg"},{"id":106403327,"identity":"6b79f443-bfbc-4987-91ef-b4b1b015beeb","added_by":"auto","created_at":"2026-04-08 09:14:05","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":174989,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eIntraoperative views illustrating the main surgical steps.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(A)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Elevation of the cutaneous flap (CF) with exposure of the temporal muscle (TM) following parotid dissection (P) and identification of the frontal and palpebral branches of the facial nerve.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(B)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Dissection and elevation of the temporal muscle (TM), exposing the underlying temporal fossa (TF).\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(C)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Resection of the temporalis fascia overlying the tumor mass, preparing the field for excision.\u003cbr\u003e\n \u003c/em\u003e\u003cem\u003e\u003cstrong\u003e(D)\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e Complete excision of the tumor with preservation of a cuff of healthy surrounding tissue\u003c/em\u003e\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/118b280ee11344607e1c9454.jpg"},{"id":106214749,"identity":"ccda935e-58ae-4b56-91f4-59dc4a49e0c1","added_by":"auto","created_at":"2026-04-06 08:16:48","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":69643,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePostoperative follow-up photograph at 2 months, showing a well-healed surgical wound with no evidence of recurrence of the temporal–infratemporal mass\u003c/em\u003e\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/0407aad39fb55ceb730d95cb.jpg"},{"id":106214750,"identity":"2237c0bd-c214-406e-9d29-825fac5210fc","added_by":"auto","created_at":"2026-04-06 08:16:48","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":87160,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePostoperative magnetic resonance imaging demonstrating a small, stable residual lesion in the deep temporal region (white arrows).\u003cbr\u003e\n(A) T2-weighted sequence showing a persistent hyperintense focus.\u003cbr\u003e\n(B) T1-weighted sequence showing the corresponding hypointense area, with no interval progression\u003c/em\u003e\u003c/p\u003e","description":"","filename":"7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/35635bb2c85451850e4099d1.jpg"},{"id":106214751,"identity":"43e84ad1-68ca-41c8-8e8e-f710645094f9","added_by":"auto","created_at":"2026-04-06 08:16:48","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":132567,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eHistological examination showing dilated cavernous vascular spaces lined by flattened endothelial cells and separated by fibrous septa within skeletal muscle tissue consistent with intramuscular cavernous haemangioma (haematoxylin and eosin stain)\u003c/em\u003e\u003c/p\u003e","description":"","filename":"8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/4b7d4911aa4643ab651ba70d.jpg"},{"id":106723711,"identity":"7c9eb9a7-cacb-459b-8fc5-50370e45301f","added_by":"auto","created_at":"2026-04-12 18:12:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1368189,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8928137/v1/948d0de0-0272-43ec-a5cf-3d60cfc99260.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Intramuscular cavernous haemangioma of the temporal muscle presenting with bone erosion and atypical radiological features","fulltext":[{"header":"Introduction","content":"\u003cp\u003eHaemangiomas are benign vascular lesions that may arise in various tissues, most commonly involving the skin and subcutaneous planes of the head and neck region [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Intramuscular haemangiomas (IMHs) are uncommon, accounting for less than 1% of all haemangiomas, and are rarely encountered in the head and neck [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Among the different histological subtypes, cavernous haemangiomas\u0026mdash;characterised by large, dilated vascular channels\u0026mdash;represent the most frequently reported variant [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. These lesions predominantly involve the masseter and trapezius muscles, whereas localisation within the temporalis muscle or extension into the infratemporal fossa remains exceptional [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe clinical and radiological presentation of cavernous haemangiomas in these deep locations is often non-specific, contributing to frequent diagnostic errors. Patients typically present with a slowly enlarging, painless mass, without associated cutaneous discolouration, bruit, or pulsatility [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. As a result, these lesions are frequently misinterpreted as more common soft-tissue tumours, including lipomas, schwannomas, neurofibromas, or other vascular malformations [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Imaging plays a central role in the diagnostic work-up, with magnetic resonance imaging (MRI) considered the modality of choice. Classically, cavernous haemangiomas demonstrate hypointense signal on T1-weighted sequences and marked hyperintensity on T2-weighted images, with heterogeneous enhancement following gadolinium administration [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. However, these radiological features are not pathognomonic and may overlap with other benign or locally aggressive entities. Moreover, fine-needle aspiration or biopsy frequently yields inconclusive results because of the vascular nature of the lesion [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eGiven their rarity, deep location, and diagnostic ambiguity, cavernous haemangiomas of the temporalis muscle and infratemporal fossa represent a particular challenge for both radiologists and surgeons. Complete surgical excision remains the treatment of choice, allowing definitive histological diagnosis and reducing the risk of recurrence [10,11]. We report a rare case of a cavernous haemangioma involving the temporo-infratemporal region, initially misdiagnosed as a lipoma, in which imaging revealed atypical features that complicated the pre-operative diagnosis and significantly influenced surgical decision-making.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eWe report the case of a 37-year-old woman with no relevant medical history who presented with a progressively enlarging left temporo-infratemporal mass. The swelling had been slowly evolving over approximately twelve years. She underwent surgical excision of the lesion in 2019 in a plastic surgery department, with histopathological analysis at that time consistent with a lipoma. However, the mass recurred within one year.\u003c/p\u003e\n\u003cp\u003eHead and neck examination revealed a firm, non-pulsatile, non-tender left temporofacial swelling, fixed to both superficial and deep planes, without inflammatory changes or fistulisation of the overlying skin (Fig. \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). No cervical lymphadenopathy was detected. Cranial nerve examination was normal; in particular, there was no peripheral facial palsy and no sensory or motor deficits were observed. Otoscopic, nasal, oral cavity, and laryngoscopic examinations were unremarkable.\u003c/p\u003e\n\u003cp\u003eRadiological evaluation over time demonstrated persistence of the left temporo-infratemporal lesion. The initial CT scan performed in 2017 showed a heterogeneous enlargement of the left temporalis muscle with adjacent fat infiltration, without evidence of bone involvement, initially suggesting an inflammatory process. In 2019, a follow-up CT scan revealed a well-defined infratemporal mass measuring 48 \u0026times; 33 \u0026times; 23 mm, extending towards the zygomatic arch and abutting the lateral pterygoid and masseter muscles, with associated bone lysis of the greater wing of the sphenoid.\u003c/p\u003e\n\u003cp\u003eFollowing surgical excision in the same year, a CT scan performed in May 2024 demonstrated recurrence of the lesion, measuring 33 \u0026times; 25 \u0026times; 26 mm, with extension into the adjacent soft tissues, yet without overtly aggressive radiological features (Fig. \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eMagnetic resonance imaging performed in December 2024 demonstrated a soft-tissue mass in the left temporo-infratemporal region measuring 60 \u0026times; 47 \u0026times; 22 mm, hypointense on T1-weighted sequences and hyperintense on T2-weighted sequences, with heterogeneous gadolinium enhancement. The lesion infiltrated the muscular plane, displaced the overlying cutaneous plane, and extended medially into the masticator space and laterally towards the masseter muscle, without evidence of cerebral or skull base invasion.\u003c/p\u003e\n\u003cp\u003eFollow-up MRI in May 2025 showed further enlargement of the lesion, measuring 63 \u0026times; 49 \u0026times; 59 mm, now associated with bone lysis of the temporal bone and extension into the temporal fossa. These imaging features raised concern for an aggressive lipomatous tumour, such as an angiolipoma (Fig. \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\n\u003cp\u003eHistopathological findings were consistent across multiple samplings. In February 2019, analysis revealed a lobulated adipose proliferation composed of mature adipocytes separated by thin fibromuscular septa, without evidence of malignancy, consistent with a benign lipoma. A subsequent biopsy in April 2019 confirmed an intramuscular lipoma, characterised by mature adipose tissue with thickened fibrous septa and regular striated muscle fibres, again without features of malignancy.\u003c/p\u003e\n\u003cp\u003eIn May 2025, the patient underwent a further biopsy under general anaesthesia through a direct incision over the left temporal region. Following subcutaneous and muscular dissection with elevation of the flaps, a reddish submuscular mass was identified beneath the temporalis muscle. Multiple biopsies were obtained for histopathological analysis, which again confirmed a benign lipomatous lesion without evidence of malignancy\u003c/p\u003e\n\u003cp\u003eA second intervention was performed in July 2025 for definitive management (Figs. \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). The procedure began with a Redon incision, allowing identification of the main trunk of the facial nerve within the parotid gland, followed by meticulous dissection and preservation of its branches, particularly the frontal and superior palpebral branches, to avoid injury during the temporal stage of the approach. The incision was then extended superiorly, curving around the insertions of the temporalis muscle at the temporal fossa and into the scalp. After elevation of the skin flap and dissection of the temporalis muscle, a venous-appearing vascular tumour was identified within the muscle fibres. The lesion retracted on compression and was confined to the thickness of the temporalis muscle. Inspection of the infratemporal fossa revealed no additional lesions\u003c/p\u003e\n\u003cp\u003eThe tumour was surgically approached and excised to the maximal safe extent. Intraoperatively, it appeared as a highly vascularised intramuscular mass involving the temporalis muscle, without extension to adjacent neurovascular structures. Owing to its marked vascular nature and the risk of excessive bleeding, complete macroscopic excision was not pursued, and a small residual component was deliberately left in situ to ensure surgical safety. Adequate haemostasis was achieved, and the temporal muscle was reconstructed by intramuscular suturing of the resected portion and reattachment to its original insertion. A suction drain was placed and subsequently removed without complication. The postoperative course was uneventful.\u003c/p\u003e\n\u003cp\u003eHistopathological examination of the excised specimen demonstrated features consistent with a cavernous haemangioma, characterised by dilated vascular channels lined by flattened endothelium, without cytological atypia or evidence of malignant transformation. The analysed surgical margins were free of tumour (Fig. \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eEarly postoperative follow-up showed satisfactory wound healing with no immediate complications. At two months, clinical examination revealed a well-healed surgical site and no clinically detectable residual mass or recurrence (Fig. \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). Follow-up magnetic resonance imaging performed at the same interval demonstrated a small, stable residual lesion within the temporalis muscle, without interval growth or pathological enhancement. These findings indicate effective surgical debulking with radiological stabilisation of the residual component and confirm a favourable short-term outcome (Fig. \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e) .\u003c/p\u003e\n\u003cp\u003eA summary of the chronological clinical course, diagnostic evaluations, and therapeutic interventions is presented in Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\" class=\"fr-table-selection-hover\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eChronological timeline of clinical presentation, diagnostic investigations, surgical interventions, and follow-up\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"2\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eYear\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eEvent\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e2017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eInitial CT scan\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eSurgical excision (lipoma diagnosis)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eRecurrence on imaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eJuly 2025\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eDefinitive surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSeptember 2025\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eStable residual lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIntramuscular haemangiomas (IMHs) are uncommon benign vascular tumours arising from skeletal muscle, accounting for less than 1% of all haemangiomas [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. They predominantly affect the trunk and extremities, whereas involvement of the head and neck region is rare, representing approximately 10\u0026ndash;15% of reported cases [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Within this anatomical area, the masseter and trapezius muscles are most frequently involved, while localisation within the temporalis muscle remains exceptional, with only a limited number of cases documented in the literature [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFrom a histopathological standpoint, intramuscular haemangiomas are classically classified into capillary, cavernous, and mixed subtypes [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Capillary haemangiomas consist of densely packed small-calibre vascular channels and represent the most common subtype overall. In contrast, cavernous haemangiomas are characterised by large, dilated blood-filled vascular spaces separated by fibrous septa [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Mixed lesions exhibit features of both patterns. Notably, although capillary haemangiomas predominate among IMHs in general, cavernous haemangiomas appear to be disproportionately represented in reported cases involving the temporalis muscle [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The histopathological findings in our case were consistent with a cavernous intramuscular haemangioma.\u003c/p\u003e \u003cp\u003eClinically, intramuscular cavernous haemangiomas typically present as a slowly enlarging, well-circumscribed intramuscular mass with indolent growth. Lesions may remain asymptomatic for prolonged periods [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Pain has been reported in approximately 30\u0026ndash;60% of cases and is often related to muscle contraction or physical activity, whereas many patients present with a painless swelling [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Cutaneous changes, pulsation, or audible bruit are usually absent, which helps distinguish these lesions from high-flow vascular malformations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The mass is generally mobile relative to the overlying skin and does not demonstrate overt invasion of adjacent structures on clinical examination.\u003c/p\u003e \u003cp\u003eBecause of this nonspecific clinical presentation, intramuscular haemangiomas are frequently misdiagnosed prior to surgery. Lipoma represents the most common initial diagnosis, followed by other benign soft-tissue tumours, cystic lesions, inflammatory processes, or, less commonly, malignant neoplasms [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. In the temporal region, the differential diagnosis also includes dermoid cysts, sebaceous cysts, temporal arteritis, and soft-tissue sarcomas. Owing to the absence of pathognomonic clinical signs, accurate preoperative diagnosis has been reported in fewer than 10% of cases [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In our patient, the lesion was initially interpreted as an intramuscular lipoma on biopsy, further illustrating the diagnostic challenge associated with these tumours.\u003c/p\u003e \u003cp\u003eImaging therefore plays a pivotal role in the evaluation of intramuscular haemangiomas. Magnetic resonance imaging (MRI) is considered the modality of choice, typically demonstrating a lesion that is isointense or hypointense relative to muscle on T1-weighted sequences and markedly hyperintense on T2-weighted images, reflecting high fluid content and slow venous flow [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Following gadolinium administration, strong and often heterogeneous enhancement is commonly observed. Computed tomography (CT) may reveal internal calcifications corresponding to phleboliths, which are present in approximately 15\u0026ndash;25% of intramuscular haemangiomas and are regarded as a suggestive imaging feature [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eImportantly, most reported cases of temporalis muscle haemangiomas do not demonstrate adjacent bone involvement [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. In contrast, our patient exhibited apparent erosion of the adjacent temporal bone, an atypical radiological finding that significantly complicated the diagnostic process and initially raised concern for a more aggressive or infiltrative lesion. This unusual imaging feature represents the principal radiological interest of the present case and highlights the potential for cavernous haemangiomas to mimic malignant soft-tissue tumours on cross-sectional imaging.\u003c/p\u003e \u003cp\u003eAlthough angiography is not routinely required, it may be useful in selected cases to delineate feeding vessels or exclude high-flow vascular malformations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, many intramuscular cavernous haemangiomas exhibit slow-flow characteristics and lack a distinct arterial blush, thereby limiting the diagnostic yield of conventional angiography.\u003c/p\u003e \u003cp\u003eDefinitive diagnosis relies on histopathological examination. Cavernous haemangiomas are composed of large, blood-filled vascular spaces lined by flattened endothelium and separated by fibrous stroma, with surrounding skeletal muscle fibres typically displaced rather than infiltrated [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These features were clearly identified in our specimen, confirming the benign nature of the lesion. Malignant transformation has not been reported in temporalis muscle haemangiomas, and no cases in the literature have demonstrated cytological atypia or invasive behaviour [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eManagement strategies depend on symptomatology, lesion size, anatomical location, growth behaviour, and cosmetic considerations. Observation may be appropriate for small, asymptomatic, and stable lesions, particularly when cosmetic impact is minimal [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Nevertheless, most reported temporalis muscle haemangiomas have been managed surgically, often because of diagnostic uncertainty or progressive enlargement [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eComplete surgical excision with a margin of normal muscle is generally advocated when feasible, as it provides definitive diagnosis and excellent local control. However, several authors have emphasised that in deeply seated or highly vascular lesions, particularly those located near critical structures, subtotal excision may represent a reasonable therapeutic compromise in order to minimise operative morbidity, provided that residual disease remains stable and is closely monitored [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. In such cases, maximal safe resection rather than radical excision is considered acceptable.\u003c/p\u003e \u003cp\u003eIn our patient, complete excision was limited by the deep location and pronounced vascularity of the tumour, necessitating intentional preservation of a small residual component within the deeper temporal fossa. Postoperative MRI confirmed the presence of a small, stable residual lesion without clinical correlate. Similar conservative surgical approaches have been reported, with favourable outcomes and no evidence of progression during follow-up [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSurgical complications are uncommon but may include injury to the temporal branch of the facial nerve. Transient postoperative eyebrow weakness has been described, typically resolving spontaneously within weeks to months [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Careful surgical technique and detailed anatomical knowledge are therefore essential.\u003c/p\u003e \u003cp\u003eOverall, the prognosis of temporalis muscle cavernous haemangiomas is excellent. Recurrence is primarily associated with incomplete excision and appears to be more frequent in capillary subtypes, whereas cavernous haemangiomas demonstrate lower recurrence rates [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Importantly, even in cases of subtotal excision, stable residual disease without progression has been reported, supporting the role of long-term clinical and radiological surveillance as an acceptable management strategy when complete resection is not feasible [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eCavernous haemangiomas of the temporalis muscle and infratemporal fossa remain exceedingly rare entities that pose significant diagnostic challenges. Their nonspecific clinical presentation and overlapping radiological features frequently lead to misdiagnosis, as exemplified in our case where bone erosion suggested an angiolipoma or more aggressive lesion. Careful interpretation of imaging studies, combined with a high index of suspicion, is therefore essential when evaluating atypical temporal or infratemporal masses.\u003c/p\u003e \u003cp\u003eHistopathological examination remains the gold standard for definitive diagnosis, while complete surgical excision continues to be the treatment of choice, both for diagnostic confirmation and for curative intent. With meticulous surgical planning, including preservation of critical neurovascular structures, outcomes are excellent and recurrence is rare when resection is complete.\u003c/p\u003e \u003cp\u003eThis case highlights the importance of considering vascular tumors, including cavernous haemangiomas, in the differential diagnosis of temporalis and infratemporal lesions, even when unusual features such as apparent bone erosion are present. Reporting such rare cases adds valuable insight to the limited body of literature and contributes to improved awareness, diagnosis, and management strategies for future patients.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch3\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThe requirement of ethical approval for this study was waived by the Ethics Committee of the Faculty of Medicine and Pharmacy of Marrakech affiliated with Mohammed VI University Hospital in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained from the patient for participation in the study and for publication of clinical data and images.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication of the clinical details and accompanying images.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article. Additional information is available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThe authors received no specific financial support for the research, authorship, or publication of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eAuthors’ contributions\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eMR: Conceptualisation, surgical management, manuscript drafting.\u003cbr\u003e\u0026nbsp;MC: Data collection and literature review.\u003cbr\u003e\u0026nbsp;SY: Radiological analysis and interpretation.\u003cbr\u003e\u0026nbsp;OO: Intraoperative assistance and data acquisition.\u003cbr\u003e\u0026nbsp;YL: Postoperative follow-up and manuscript revision.\u003cbr\u003e\u0026nbsp;YR: Supervision and critical revision of the manuscript.\u003cbr\u003e\u0026nbsp;AR: Senior supervision, validation of surgical strategy, and final approval of the manuscript.\u003cbr\u003e\u0026nbsp;All authors read and approved the final manuscript.\u003c/p\u003e\n\u003ch3\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThe authors and the Department of Otolaryngology – Head and Neck Surgery would like to thank Dr. Mohammed Rami for the hand-drawn illustration presented in Fig. 4, depicting the key surgical steps of the infratemporal approach.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eOrly J, Bisdorff A, Fraissenon A, Joly A, Boulouis G, Guibaud L, Tavernier E, Mallet S, Marcelin C, Miquel J, Martin L, Droitcourt C, Gusdorf L, Abasq C, Dadban A, Chiaverini C, Vabres P, Herbreteau D, Boccara O, Wassef M, Maruani A. Intramuscular capillary-type hemangioma: diagnosis, treatment, and outcomes: a French multicentric retrospective study of 66 cases. \u003cstrong\u003eEur J Radiol\u003c/strong\u003e. 2023;165:110962. https://doi.org/10.1016/j.ejrad.2023.110962\u003c/li\u003e\n\u003cli\u003eAlmousa HM, Albesher MB, Alsolami AL, Al Mutairy AS. Intramuscular haemangioma of the sternocleidomastoid: a rare tumour in an unusual location. \u003cstrong\u003eEar Nose Throat J\u003c/strong\u003e. 2023. Epub ahead of print. https://doi.org/10.1177/01455613231189148\u003c/li\u003e\n\u003cli\u003eDu J, Li K, Wang W, Jhonatan FY, Zhang W, Yang H, et al. Qualitative and quantitative diagnosis of intramuscular haemangioma subtypes: comparison of ESWAN and conventional MRI. \u003cstrong\u003eActa Radiol\u003c/strong\u003e. 2023;64(1):208\u0026ndash;216.\u003c/li\u003e\n\u003cli\u003eLai KKH, Li CK, Tsang A, Wong SYS, Ko CKL. Ocular adnexal intramuscular haemangioma arising from the eyelid: case report and literature review. \u003cstrong\u003eOrbit\u003c/strong\u003e. 2023;42(3):290\u0026ndash;294.\u003c/li\u003e\n\u003cli\u003eLiu D, Bao Y, Wang Y, Lu X, Shen J, Huang S, et al. Case report: intercostal intramuscular haemangioma with sternal invasion. \u003cstrong\u003eFront Oncol\u003c/strong\u003e. 2024;14:1360626. https://doi.org/10.3389/fonc.2024.1360626\u003c/li\u003e\n\u003cli\u003eOrly J, Bisdorff A, Joly A, Edee AE, Tavernier E, Herbreteau D, et al. Characteristics, natural course and treatment of intramuscular capillary-type haemangioma: a systematic literature review. \u003cstrong\u003eActa Derm Venereol\u003c/strong\u003e. 2023;103:adv00893. https://doi.org/10.2340/actadv.v103.4432\u003c/li\u003e\n\u003cli\u003eFeger J, Ranchod A, Campos A, et al. Intramuscular haemangiomas. \u003cstrong\u003eRadiopaedia.org\u003c/strong\u003e [Internet]. 2024 [cited 2026 Feb 20]. Available from: https://radiopaedia.org/articles/intramuscular-haemangiomas\u003c/li\u003e\n\u003cli\u003eJoud B, Beqqali B, Loubaris S, El Beyeg M, Zamani O, Kaoutar Z, et al. Exceptional localization of intramuscular haemangioma: insights from a case report. \u003cstrong\u003eRadiol Case Rep\u003c/strong\u003e. 2025. Epub ahead of print.\u003c/li\u003e\n\u003cli\u003eMurakami K, Shinohara T, Saito K, Hoshino T. Intramuscular haemangioma of the temporalis muscle. \u003cstrong\u003eJ Oral Maxillofac Surg\u003c/strong\u003e. 1991;49(9):1008\u0026ndash;1012.\u003c/li\u003e\n\u003cli\u003eAllen PW, Enzinger FM. Haemangioma of skeletal muscle. \u003cstrong\u003eCancer\u003c/strong\u003e. 1972;29(1):8\u0026ndash;22.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Medicine](https://link.springer.com/journal/44337)","snPcode":"44337","submissionUrl":"https://submission.springernature.com/new-submission/44337/3","title":"Discover Medicine","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Intramuscular haemangioma, Cavernous haemangioma, Temporalis muscle, Bone erosion, Magnetic resonance imaging, Diagnostic pitfall","lastPublishedDoi":"10.21203/rs.3.rs-8928137/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8928137/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eIntramuscular cavernous haemangiomas are rare benign vascular tumours, particularly when arising in the temporalis muscle or infratemporal fossa. Radiological diagnosis is challenging because imaging features often overlap with those of other benign soft-tissue lesions, and bone involvement is considered unusual. To our knowledge, bone erosion associated with temporalis intramuscular cavernous haemangioma has been rarely described in the literature.\u003c/p\u003e\u003ch2\u003eCase presentation :\u003c/h2\u003e \u003cp\u003eWe report the case of a 37-year-old woman with a slowly progressive left temporo-infratemporal mass evolving over 12 years and repeatedly diagnosed as a lipoma. Cross-sectional imaging revealed a deeply located, highly vascularised intramuscular lesion with atypical radiological features, notably erosion of the adjacent temporal bone and the greater wing of the sphenoid. Magnetic resonance imaging demonstrated a heterogeneous mass, hypointense on T1-weighted sequences and markedly hyperintense on T2-weighted sequences, with intense heterogeneous enhancement following gadolinium administration. Because of the apparent aggressive imaging behaviour, malignant or invasive lipomatous tumours were initially suspected. Surgical management consisted of maximal safe excision via an infratemporal approach, leaving a small deep residual component due to excessive vascularity. Histopathological examination confirmed a cavernous intramuscular haemangioma. Post-operative follow-up MRI demonstrated a small, stable residual lesion without progression.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis case emphasises the importance of radiological evaluation in intramuscular haemangiomas occurring at rare locations. Although cavernous haemangiomas are classically non-invasive, associated bone erosion may occur and represent a diagnostic pitfall, potentially mimicking aggressive neoplastic processes. Awareness of this atypical imaging presentation can help avoid misdiagnosis and guide appropriate surgical management.\u003c/p\u003e","manuscriptTitle":"Intramuscular cavernous haemangioma of the temporal muscle presenting with bone erosion and atypical radiological features","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-06 08:16:43","doi":"10.21203/rs.3.rs-8928137/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-04-16T16:25:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"225836765476672519691940313120228376847","date":"2026-04-07T06:24:58+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-03T20:55:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"293885325422509744908405649277426769560","date":"2026-04-02T11:25:29+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-01T16:26:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"137192361032696460394026117837564363225","date":"2026-04-01T16:13:42+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-01T08:51:16+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-03T06:59:56+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-28T07:28:17+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-28T00:11:46+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Medicine","date":"2026-02-27T20:51:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Medicine](https://link.springer.com/journal/44337)","snPcode":"44337","submissionUrl":"https://submission.springernature.com/new-submission/44337/3","title":"Discover Medicine","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b9345df1-f726-4efa-b77e-ebe5ae4e5508","owner":[],"postedDate":"April 6th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-06T08:16:44+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-06 08:16:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8928137","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8928137","identity":"rs-8928137","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}