Cavernous Venous Malformation Research Articles

Comparative characteristics of ophthalmological symptoms of orbitocranial and orbital cavernous venous malformation

BACKGROUND: Cavernous venous malformation of the orbit, formerly known as cavernous hemangioma of the orbit, refers to vascular malformations with slow blood flow, and is a frequent lesion of the orbit in adults. The spread of cavernous venous malformation of the orbit into the cranial cavity is extremely rare.
 AIM: The aim of this study is a comparative analysis of ophthalmological manifestations of orbitocranial and orbital cavernous venous malformation.
 MATERIALS AND METHODS: The analysis was performed on 50 patients operated in N.N. Burdenko National Scientific and Practical Center for Neurosurgery from 2004 till 2023. Two groups of patients with сavernous venous malformation of the orbit were identified: group 1 — with malformation spreading into the cranial cavity, group 2 —with malformation localized in the orbit only.
 RESULTS: In 29 patients, cavernous venous malformation of the orbit spread into the cranial cavity through superior orbital fissure, inferior orbital fissure, optic canal and/or through combinations thereof; in 21 patients, the malformation was located in the orbit only. Females prevailed in both groups; the average age was 44 years. The first group included patients with the following features: visual impairments were more frequent and more prominent, oculomotor disorders caused mainly by the involvement of oculomotor and abducens nerves; optic nerve atrophy, slight proptosis. The second group was identified by more prominent proptosis, more mild visual impairments, oculomotor disorders caused by the presence of the malformation in the orbit, at the eye fundus, optic nerve head edema prevailed.
 CONCLUSIONS: Ophthalmic symptoms due to topographic and anatomical variants of a cavernous malformation.

Emerging Trends & Techniques Related to Treatment in Patients with intra – Conal Cavernous Hemangioma of the Orbit(OCH)/orbital Cavernous Malformation (OCVM) and Treatment related Complications, A Systematic Review

Orbital Cavernous venous malformation (OCVM), formerly known as cavernous hemangioma of the orbit (OCH) is a frequent benign, slow-growing, non distensible venous malformation with ISSVA classification which classifies it into different types. This research has employed randomized controlled trials (RCTs), case reports, retrospective case studies, systematic reviews, and cohort studies to evaluate the treatment choices for OCVM and its consequences. The goal of this review is to analyze the comprehensive therapies used for OCVM. For our literature search, we looked at PubMed/MEDLINE, PubMed Central and Cochrane across six years (from 2016 to 2021). Using the Cochrane risk of bias quality assessment tool, the found studies underwent a quality check (modified Cochrane RoB 2). For the reporting of this systematic review, we adopted preferred reporting items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 criteria and included a total of 10 papers. The majority of research confirmed the accuracy of OCVM detection using MRI and CT. To evaluate the effects of the intervention on OCVM more precisely, more trials with a longer follow-up time are needed. This study will explore recommendations and guide orbital surgeons, regardless. It will aid in the development of future strategies involving both invasive and noninvasive procedures to close the surgical and complication gap.

Orbital Cavernous Venous Malformation in a 35-Year-Old Man: A Case Report

In this article we present a case of a 35-year-old patient with a massive 43 × 35 × 34 mm cavernous venous malformation of the left orbit. The orbital lesion was initially observed in 2008 and remained untreated to 2021 due to the patient’s refusal to consent to the surgical procedure; which caused the tumor to grow to monstrous dimensions.

A signature of structural MRI features at 3 Tesla allows an accurate characterization of orbital cavernous venous malformation.

To differentiate OCVM from other orbital lesions using structural MRI. This IRB-approved a historical-prospective cohort single-center analysis of a prospective cohort that included consecutive adult patients presenting with an orbital lesion undergoing a 3T MRI before surgery from December 2015 to May 2021. Two readers blinded to all data read all MRIs assessing structural MRI characteristics. A univariate analysis followed by a stepwise multivariate analysis identified structural MRI features showing the highest sensitivity and specificity when diagnosing OCVM. One hundred ninety-one patients with 30/191 (16%) OCVM and 161/191 (84%) other orbital lesions were included. OCVM were significantly more likely to present with a higher signal intensity than that of the cortex on T2WI: 26/29 (89.7%) versus 28/160 (17.5%), p < 0.001, or with a chemical shift artifact (CSA): 26/29 (89.7%) versus 16/155 (10.3%), p < 0.001, or to present with a single starting point of enhancement, as compared to other orbital lesions: 18/29 (62.1%) versus 4/159 (2.5%), p = 0.001. The step-wise analysis identified 2 signatures increasing performances. Signature 1 combined a higher signal intensity than that of the cortex on T2WI and a CSA. Signature 2 included these two features and the presence of a single starting point of enhancement. Sensitivity, specificity, and accuracy were 0.83, 0.94, and 0.92 for signature 1 and 0.97, 0.93, and 0.93 for signature 2, respectively. Structural MRI yields high sensitivity and specificity when diagnosing OCVM. • Structural MRI shows high sensitivity and specificity when diagnosing orbital cavernous venous malformation. • We identified two signatures combining structural MRI features which might be used easily in routine clinical practice. • The combination of higher signal intensity of the lesion as compared to the cortex on T2WI and of a chemical shift artifact yields a sensitivity and specificity of 0.83 and 0.94 for the diagnosis of orbital cavernous venous malformation, respectively.

Cerebellar hemorrhage in a healthy young adult: a case report

BackgroundCavernous venous malformation is an uncommon entity that occurs in around 0.5% of the general population. Cerebellar cavernous venous malformation accounts for 1.2–11.8% of intracranial cavernous venous malformation cases. Patients are commonly asymptomatic until a hemorrhage occurs. In approximately 20% of the cases, cavernous venous malformation and developmental venous anomalies occur together, called mixed vascular malformation. Our case report reveals the imaging features of the mixed vascular malformation and highlights the appropriate imaging modality and sequence to detect the abnormalities.Case presentationWe report the case of a 15-year-old Malay male, a healthy young male who presented with dizziness, vomiting, and mild headache for 1 month. Computed tomography brain imaging at presentation revealed cerebellar hemorrhage with multiple cavernous venous malformation and coexisting developmental venous anomalies, which was then confirmed by magnetic resonance imaging. The patient was started on dexamethasone 4 mg four times a day, observed in the ward, and discharged well without neurological sequelae.ConclusionA cavernous malformation with concurrent developmental venous anomalies requires accurate diagnosis. Our case report contributes to the literature on the imaging diagnosis of this disease, which is beneficial for current and future reference.

A clinicopathological reappraisal of orbital vascular malformations and distinctive GJA4 mutation in cavernous venous malformations

Vascular anomalies are common orbital lesions, while variations in previous nomenclature might hamper robust characterization of their clinicopathological and genetic features. We reviewed and reclassified 92 orbital vascular lesions by the modified International Society for the Study of Vascular Anomalies (ISSVA) classification with reappraising clinicopathological parameters of 4 main types of vascular malformations, including orbital venous malformation 1 (OVM1, cavernous venous malformation), OVM2 (varix), OVM3 (infiltrating venous malformation), and arteriovenous malformation (AVM). GJA4, BRAF, and KRAS mutations were assessed by Sanger sequencing. There were 90 cases of vascular malformations, consisting of 60 OVM1 (67%), 13 AVM (14%), 8 OVM2 (9%), 8 OVM3 (9%), and 1 lymphatic-venous malformation (1%). The prevailing OVM1, histologically characterized by well-delineated borders and a uniform cavernous growth pattern, predominantly occurred in intraconal space (57%, P=.019) with an older median age (49 years) and female predilection (73%). OVM2, OVM3, and AVM exhibited differences in the distributions of patients' ages and lesion locations. Sizes of lesions were significantly correlated with periorbital and intraconal/extraconal locations (P<.001). OVM1 had the lowest rate of residual and recurrent diseases (3%). GJA4 mutations were identified in 75% (44/59) of OVM1 but not in OVM2/3 and AVM. No BRAF or KRAS mutations were detected. In conclusion, the modified ISSVA scheme enables meaningful classification of orbital vascular malformations by highlighting the molecular correlation between the distinct clinicopathological features and specific GJA4 mutation in OVM1, which implies OVM1 as a unique variant of venous malformation genetically akin to cutaneous and hepatic counterparts.

Somatic GJA4 gain-of-function mutation in orbital cavernous venous malformations

Orbital cavernous venous malformation (OCVM) is a sporadic vascular anomaly of uncertain etiology characterized by abnormally dilated vascular channels. Here, we identify a somatic missense mutation, c.121G > T (p.Gly41Cys) in GJA4, which encodes a transmembrane protein that is a component of gap junctions and hemichannels in the vascular system, in OCVM tissues from 25/26 (96.2%) individuals with OCVM. GJA4 expression was detected in OCVM tissue including endothelial cells and the stroma, through immunohistochemistry. Within OCVM tissue, the mutation allele frequency was higher in endothelial cell-enriched fractions obtained using magnetic-activated cell sorting. Whole-cell voltage clamp analysis in Xenopus oocytes revealed that GJA4 c.121G > T (p.Gly41Cys) is a gain-of-function mutation that leads to the formation of a hyperactive hemichannel. Overexpression of the mutant protein in human umbilical vein endothelial cells led to a loss of cellular integrity, which was rescued by carbenoxolone, a non-specific gap junction/hemichannel inhibitor. Our data suggest that GJA4 c.121G > T (p.Gly41Cys) is a potential driver gene mutation for OCVM. We propose that hyperactive hemichannel plays a role in the development of this vascular phenotype.

Giant Cavernous Venous Vascular Malformation of Glans and Distal Penis in a Toddler Successfully Treated by Steroids and Subsequent Circumcision

We wish to report a very rare and interesting case of a 3-year-old toddler boy who presented with request for cultural circumcision.

Disorders of the Angular Vein.

The angular vein extends between the supraorbital and supratrochlear veins superiorly and the facial vein inferiorly. Rarely, this vessel can be involved by infections, vascular malformations, or benign tumors. In this study, we report both our experience and the published literature on angular vein disorders. A retrospective study was performed on patients seen between 2008 and 2022. The medical literature was searched for reports of conditions affecting the angular vein. During the study period, we encountered 5 patients with angular vein disorders. Information from these patients was combined with 18 published cases. Among the 23 patients, the diagnosis was confused with lacrimal drainage abnormalities in 52%, and 57% underwent imaging. "Swelling" or a palpable, moveable mass were frequent findings. Pain or tenderness was experienced by 43.5% of patients. Five patients were observed, and 2 infections were treated with antibiotics. The remaining 16 lesions were successfully treated with excision (n = 15) or cauterization (n = 1), without complications. Final diagnosis included 14 vascular malformations (isolated varix: 7, thrombosis: 6, cavernous venous malformation: 1), 7 vascular tumors (intravenous pyogenic granulomas: 6, intravascular papillary endothelial hyperplasia: 1) and thrombophlebitis (n = 2). Disorders of the angular vein are uncommon and frequently misdiagnosed as lacrimal abnormalities. While these lesions can frequently be identified on clinical findings, imaging can be helpful in some cases. Patients with suspected thrombophlebitis require urgent antibiotic therapy. Minimally symptomatic angular vein lesions can be observed. Surgical excision is effective in treating the different vascular malformations and tumors affecting this structure.

Combined Endonasal and Orbital Approach for Resection of Orbital Apical Tumors.

Tumors of the medial orbital apex can be challenging to resect. Primary endonasal resection can be limited by requirements for fat retraction and poor angulation for lateral orbital dissection. Orbital resection alone can have space limitations and a limited view for dissection of the posterior aspect of the tumor. The combined transorbital transnasal approach integrates the retraction and instrumentation advantages of the transorbital approach with the optical and space advantages of the transnasal approach. In this cross-sectional cohort study, patients who underwent surgical resection of an apical orbital tumor via a combined endoscopic and orbital approach from 2014 to 2019 were identified. Clinical history, examination findings, imaging, surgical technique, histopathology, and complications were reviewed. Six patients were included. Patients presented with proptosis (5), optic neuropathy (3), and motility restriction (2). Surgery involved a medial orbitotomy and endoscopic ethmoidectomy ± sphenoidotomy, medial wall removal, and periosteum opening. The lesion was prolapsed into the sinus, dissected at the apex via the orbital approach, and removed through the nasal cavity. Pathologic diagnoses were cavernous venous malformation (4), venolymphatic malformation (1), and metastatic carcinoid (1). Improvement in pain (2/2), optic neuropathy (2/3), and proptosis (5/5) were noted. Complications included ethmoid mucocele and nasal polyps. The combined endonasal and orbital approach involves prolapsing the lesion into the nasal cavity to aid in dissection on the lateral and posterior aspects, maximizing visibility of the tight intraconal space. This technique can be performed by a team of orbital surgeons experienced in both orbital and endonasal surgery.

Prognosis Analysis and Clinical Features of Orbital Cavernous Venous Malformations With Refractory Insidious Onset.

ObjectiveThe present study aims to analyse the clinical presentation, treatment and prognosis of a group of patients with orbital cavernous venous malformation (OCVM) with an insidious onset.MethodThe clinical data of 35 patients with OCVM treated at our centre between 2003 and 2020 were retrospectively analysed. The OCVMs were classified as one of six types (I–VI) according to the orbital position of the tumour. The clinical characteristics, treatment methods and follow-up results were recorded.ResultsA total of 35 patients with OCVM under the optic nerve sheath in the orbital apex area or the common tendon ring (Types I and II) were included in the present study. In 20 cases (57.1%), patients were misdiagnosed with optic neuritis, and in 20 cases (57.1%), the tumour was not identified based on imaging. The presentation was acute or subacute in 23 cases (65.7%). All patients underwent surgery: transnasal surgery in 22 cases (62.9%) and craniotomy in 13 cases (37.1%). A total of 9 patients (25.7%) experienced postoperative complications, and 17 patients (48.6%) experienced vision improvement. The average patient age at first diagnosis was 43.3 ± 10.3 years, and the median follow-up period was 64.5 months. Overall, 14 patients (40%) experienced postoperative complications: postoperative blindness in 6 cases, postoperative vision loss in 8 cases and orbital apex syndrome in 7 cases.ConclusionPatients with Type I and Type II OCVMs are the most complex cases. They have an insidious onset and are associated with a high rate of misdiagnosis and missed diagnosis. Acute and subacute decreases in visual acuity are mainly caused by OCVM haemorrhage. The difficulty of surgical treatment and the poor prognosis of postoperative vision are characteristics of this tumour. Transnasal surgery and craniotomy can be used to remove OCVMs located in the common tendon ring or optic canal as well as those involving the intracranial area through the supraorbital fissure. Meanwhile, the orbital approach (orbitotomy) has proven to be an effective method of treating OCVMs not involving the deep orbital apex and intracranial area.

Cellular heterogeneity and immune microenvironment revealed by single-cell transcriptome in venous malformation and cavernous venous malformation

Venous malformation (VM) and cavernous venous malformation (CVM) are two types of vascular malformations. Even if the two diseases are similar in appearance and imaging, the distinct cellular components and signaling pathways between them might help distinguish the two from a molecular perspective. Here, we performed single-cell profiling of 35,245 cells from two VM samples and three CVM samples, with a focus on endothelial cells (ECs), smooth muscle cells (SMCs) and immune microenvironment (IME). Clustering analysis based on differential gene expression unveiled 11 specific cell types, and determined CVM had more SMCs. Re-clustering of ECs and SMCs indicated CVM was dominated by arterial components, while VM is dominated by venous components. Gene set variation analysis suggested the activation of inflammation-related pathways in VM ECs, and upregulation of myogenesis pathway in CVM SMCs. In IME analysis, immune cells were identified to accounted for nearly 30% of the total cell number, including macrophages, monocytes, NK cells, T cells and B cells. Notably, more macrophages and monocytes were discovered in VM, indicating innate immune responses might be more closely related to VM pathogenesis. In addition, angiogenesis pathway was highlighted among the significant pathways of macrophages & monocytes between CVM and VM. In VM, VEGFA was highly expressed in macrophages & monocytes, while its receptors were all abundantly present in ECs. The close interaction of VEGFA on macrophages with its receptors on ECs was also predicted by CellPhoneDB analysis. Our results document cellular composition, significant pathways, and critical IME in CVM and VM development.

Clinico-epidemiological analysis of 1000 cases of orbital tumors.

To clarify the incidence, demography and clinical features of orbital tumors diagnosed in a single institute in Japan. Retrospective, observational case series. Patients with primary orbital tumors including tumor-like lesions diagnosed clinically or histopathologically at Tokyo Medical University Hospital between 1995 and 2019 were analyzed. Incidence of all orbital tumors, demographic profile and clinical features of major benign and malignant tumors were reviewed retrospectively. Totally 1000 cases of primary orbital tumor were diagnosed clinically or histopathologically during the study period. Benign tumors accounted for 72% and malignant tumors 28%. 55% of benign tumors and 99% of malignant tumors were proven histopathologically. The most common benign orbital tumor was idiopathic orbital inflammation (27%), followed by IgG4-related ophthalmic disease (17%), cavernous venous malformation (13%) and pleomorphic adenoma (9%). The most common malignant tumor was lymphoma (70%), followed by adenoid cystic carcinoma (7%) and solitary fibrous tumor (5%). Epidemiology of orbital tumors has changed by the improvement of imaging techniques, establishment of novel clinical and histopathological criteria, and changes in population age structure associated with the aging society. Currently, lymphoproliferative diseases including lymphoma and IgG4-related ophthalmic diseases form the major orbital tumors in Japan.

Orbital Vascular Anomalies: A Nomenclatorial, Etiological, and Nosologic Conundrum.

Vascular anomalies are a heterogeneous group of disorders that frequently present in the periorbital region. They encompass 2 broad entities: vascular tumors, which possess a proliferative endothelium, and vascular malformations, which are basically localized defects of vascular morphogenesis. The primary goal of this review was to address inaccurate or controversial terminology in the oculoplastic literature concerning orbital and periorbital vascular anomalies and to categorize these lesions in an abridged and simplified hierarchical list that adheres as much as possible to the most recent (2018) iteration for the classification of vascular lesions proposed by the International Society for the Study of Vascular Anomalies (ISSVA). The secondary goal of this review was to review and update information regarding the genetic underpinnings of vascular anomalies and the downstream signaling pathways that are subsequently affected as a result of these genetic errors. A literature review was conducted in PubMed, MEDLINE, PubMed Central, National Center for Biotechnology Information Bookshelf, and Embase for several related keywords including "vascular anomalies, vascular malformations, vascular tumors, and cavernous venous malformation," both with and without adding the keywords "eyelid," "orbital," and "periorbital." In addition, a detailed search was conducted for controversial or obsolete keywords like "cavernous hemangioma," "lymphangioma," and "varices," again in their systemic and orbital/periorbital context. Crucial issues in the 2018 ISSVA classification regarding the proper categorization of orbital vascular anomalies, particularly venous lesions, were critically evaluated and revised, and a regional, simplified, and abridged modification of the ISSVA 2018 classification was proposed. Interdisciplinary and intradisciplinary dialogue concerning orbital vascular anomalies is seriously compromised due to the lack of a unanimous agreement on terminology and the absence of a unified classification concept system. The authors recommend that oculoplastic surgeons adopt ISSVA terminology whenever technically possible and scientifically sound. However, they also propose modifying the ISSVA 2018 classification specifically to adapt to the peculiarities of vascular anomalies in the periorbital region. At present, the simplified classification proposed here is a preliminary first step towards managing patients with orbital vascular anomalies with greater diagnostic and therapeutic precision, until such time in the future when the entire genetic makeup of orbital vascular anomalies is more completely elucidated. Optimistically, this could pave the way for a more robust classification and the ultimate therapeutic cure.

Navigation-Guided Nasal Endoscopy to Remove the Cavernous Venous Malformation of the Orbital Apex Through the Sphenoid Approach.

To explore the feasibility of navigation-guided sinus endoscopy to remove the cavernous vascular malformation of the orbital apex through the sphenoid approach. A retrospective series of non-control cases were collected. From May 2012 to December 2019, patients with imaging findings of cavernous venous malformation in the orbital apex were collected at the Eye Hospital Affiliated to Nanchang University. All patients underwent navigation guided sinusoscopy through the sphenoid approach to remove the cavernous venous malformation of the orbital apex. Analyze the changes of visual function and postoperative complications before and after operation. Twelve patients were collected, including 3 males and 9 females aged between 32 and 59. In 3 patients without visual impairment, the postoperative visual function was still normal. The remaining 9 patients all had visual impairment. Among them, 3 patients had fully recovered normal visual function after operation, 2 patients had improved visual function compared with preoperative, and 4 patients had no change in postoperative visual acuity. There were no complications in 3 of the 12 patients, and 9 patients had transient limited intraocular rotation with mild limitation of diplopia after operation, and all returned to normal within 1 month after surgery. Navigation-guided sinus endoscopy through the sphenoid approach to remove the cavernous venous malformation of the orbital apex is an effective and feasible surgical method.

Cavernous venous malformation of the lacrimal gland

Cavernous venous malformation (CVM) is a common benign vascular lesion of the orbit. It was previously known as "orbital cavernous hemangioma". Localization within the lacrimal gland is extremely rare. We describe the case of a 76-year-old man with an asymptomatic CVM of the left lacrimal gland incidentally discovered on a routine MRI. A curative and diagnostic en bloc surgical resection was performed, allowing for histological diagnosis. CVM of the lacrimal gland is extremely rare and usually asymptomatic. Proptosis is the main symptom. On MRI, the lesion appears hypointense with heterogeneous enhancement after Gadolinium injection on T1-weighted imaging and hyperintense on T2 STIR-weighted imaging. Histological examination is mandatory for the diagnosis. Surgical resection is usually performed.

Stereotactic radiosurgery for orbital cavernous venous malformation: a single center's experience for 15 years.

Stereotactic radiosurgery such as Gamma Knife radiosurgery (GKRS) has been shown to have a good treatment effect for orbital cavernous venous malformation (CVM). However, radiation-induced retinopathy or optic neuropathy is a vision-threatening complication of orbital irradiation. Predicting the post-treatment visual outcome is critical. Clinical and radiological outcomes were investigated in 30 patients who underwent GKRS for orbital CVM between July 2005 and February 2020. Measurement of peripapillary retinal nerve fiber layer (pRNFL) thickness using optical coherence tomography (OCT) was obtained in 14 patients. The median clinical and radiological follow-up periods were 46.6 months (range, 15.9-105.8) and 27.5 months (range, 15.4-105.8), respectively. Twenty-eight patients underwent multisession (4 fractions) GKRS. The median cumulative marginal dose was 20 Gy (range, 16-24). Two patients underwent single-session GKRS. Marginal doses were 15 Gy and 10.5 Gy in each patient. The volume of CVM decreased in 29 (97%) patients. Visual acuity was improved in 6 (20%) patients and was stable in 22 (73%) patients. Visual field defect and exophthalmos were improved in all patients. Serial investigation of OCT showed no statistically significant difference in pRNFL thickness after GKRS. Patients with normal average pRNFL thickness showed better visual recovery than patients with thin average pRNFL thickness. GKRS is an effective and safe treatment option for orbital CVM. The pRNFL thickness before GKRS can be a prognostic indicator for visual recovery in orbital CVM after GKRS.

Risks and Benefits of Surgical Excision of Orbital Cavernous Venous Malformations (So-Called Cavernous Hemangioma): Factors Influencing the Outcome

To assess risks and benefits associated with surgical excision of orbital cavernous venous malformation and analyze factors influencing the outcome. Design: cohort study. Participants: 164 consecutive patients undergoing surgical removal of orbital cavernous venous malformation. Intervention: lateral or anterior orbitotomy. Outcome measures: visual acuity, visual field, pupillary function, ocular motility, and fundus examination. Influence of the mass volume and tumor location on the outcome was evaluated. The threshold value and risk group for the volume were evaluated using the receiver operating characteristic analysis; 8 orbital different quadrants, extraconal/intraconal position, and orbital apex extension were considered as variables to evaluate the location. Postoperatively overall visual acuity (p = 0.0084), visual field (p < 0.0001), diplopia (p < 0.0001), proptosis (p < 0.0001), ocular motility (p = 0.02), ptosis (p = 0.033), choroidal fold (p < 0.0001), disk edema (p = 0.0004) were significantly improved. The commonest location was the lateral quadrant (28%). Choroidal folds were associated with tumor greater than 1100 mm3 (p = 0.001). Visual loss occurred in 2 patients (1.2%) and tonic pupil in 5 (3%,) Visual deterioration was associated with the apical extension (p = 0.001). Pupil efferent defect was associated with lateral quadrant location (p = 0.011) and apical extension (p = 0.05). Surgical removal of orbital cavernous venous malformation is a useful treatment modality, particularly for large size tumors. Removal of cavernous venous malformations located at the lateral aspect of the orbit carries an increased risk of permanent tonic pupil. Postoperative blindness is rarely seen and is often associated with the apical extension. Tailoring the surgical approach, depending on the relative position to the optic nerve, may have an important bearing on outcome.

Near fatal haemorrhage in neurofibromatosis type 1 associated with occult giant cavernous venous malformation.

Near fatal haemorrhage in neurofibromatosis type 1 associated with occult giant cavernous venous malformation.

Intramuscular cavernous venous malformation of extraocular muscles. Fractionated stereotactic radiotherapy as a therapeutic alternative

Intramuscular cavernous venous malformations affecting extraocular muscles are extremely uncommon. Due to their location, complete resection could be difficult. A clinical case is presented of an inferior rectus muscle orbital cavernous malformation treated with fractionated stereotactic radiotherapy after post-surgical excision recurrence. The malformation responded to radiotherapy with a reduction in size and symptoms. Fractionated stereotactic radiotherapy is an alternative and effective treatment for cavernous venous malformations that are surgically challenging due to their radiotherapy sensitivity.