Brainstem cavernous hemangioma with improvement of Holmes tremor on excision.

An 8-year-old boy presenting with left-angle paralysis, tremor in upper and lower extremities, and diplopia was diagnosed with hemorrhage from a mesencephalic cavernous hemangioma. He underwent hemangiomectomy through the occipital transtentorial approach 4 weeks post-hemorrhage, after which Holmes tremor (HT) markedly reduced. A year later, hemangioma has not recurred; he is now independent in his daily activities. Early intervention in the subacute stage allows for the complete removal of brainstem cavernomas (BSCs), with minimal risk of complications or sequelae. Proper timing and surgical approach for BSCs can prevent re-bleeding and improve HT after an initial hemorrhage, without any lasting negative consequences.

Thoracic root-related intradural extramedullary cavernoma presenting with subarachnoid hemorrhage: illustrative case.

BACKGROUND: Just 5% of all cavernomas are located in the spine. Thoracic root-related subtypes are the rarest, with a total of 14 cases reported in the literature to date. Among them, only 4 presented with subarachnoid hemorrhage (SAH). OBSERVATIONS: A 65-year-old female presented after an ictus of headache with no neurological deficits. Computed tomography (CT) demonstrated sulcal SAH, with the remainder of the workup nondiagnostic for etiology. Three weeks later, she re-presented with acute thoracic back pain and thoracic myelopathy. CT and magnetic resonance imaging suggested dubiously a T9-10 disc herniation with spinal cord compression. Surgical decompression and resection were then planned. Intraoperative ultrasound (IUS) demonstrated an intradural extramedullary lesion, confirmed to be cavernoma. Complete resection was achieved, and the patient was discharged a few days postoperatively to inpatient rehabilitation. LESSONS: Although spine imaging is deemed to be low yield in the evaluation of cryptogenic SAH, algorithms can be revisited even in the absence of spine-related symptoms. Surgeons can be prepared to change the initial surgical plan, especially when preoperative imaging is unclear. IUS is a powerful tool to assess the thecal sac after its exposure and to help guide this decision, as in this rare entity.

Clinical course of patients with conservatively managed cerebral cavernous malformations.

INTRODUCTION: There is uncertainty whether patients with a cerebral cavernous malformation (CCM) should undergo conservative or surgical treatment, resulting in practice variation among hospitals. Our objective was to report clinical outcomes of patients with primarily conservatively managed CCMs. PATIENTS AND METHODS: This single-center cohort study included consecutive adult CCM patients, diagnosed in 2000-2023, who underwent conservative management as primary treatment strategy. Data were extracted from medical records, and we systematically conducted telephone and questionnaire follow-up. Functional status was assessed on the modified Rankin Scale (mRS). RESULTS: Of 345 patients, we included 265 patients with a CCM (median age 46 years; 45% male). At baseline, 131 (49%) patients presented with symptomatic hemorrhage (SH), and 134 (51%) with other symptoms or asymptomatically. During 58 months (IQR 35-94) median follow-up, 51 (19%) patients experienced a SH, 33 (12%) a seizure, and 13 (5%) focal neurological deficits. Fourteen (5%) patients underwent intervention (surgery n = 11, radiosurgery n = 4). Presentation with SH was associated with higher annual bleeding rates (6.0% vs 1.5%, p < 0.001), and higher cumulative 5-/10-year bleeding risks (31%/41% vs 7%, p < 0.001). Brainstem CCM was associated with higher cumulative 5-/10-year bleeding risks (27%/38% vs 17%/21%, p = 0.038). Nineteen (7%) patients died; two (0.8%) directly attributable to CCM. Of 246 surviving patients, 205 (83%) completed the questionnaire. At follow-up, 172/224 (77%) patients were functionally independent (mRS score ⩽2). DISCUSSION AND CONCLUSION: The majority of conservatively managed CCM patients remained free of a SH during follow-up. Few patients required intervention, and death attributable to the CCM was rare. These data may help patient counseling and treatment decisions.

Stereotactic radiosurgery for intracranial cavernous malformations of the deep-seated locations: systematic review and meta-analysis.

OBJECTIVE: To determine the outcomes of stereotactic radiosurgery (SRS) for deep-seated (brainstem, basal ganglia, thalamus, cerebellar peduncle) intracranial cavernous malformations (ICMs). METHODS: A systematic review and meta-analysis was performed according to PRISMA and MOOSE guidelines. The main outcomes were comparing pre- and post-SRS hemorrhage rates, using the pooled risk ratios (RR) as the measure of effect. Additionally, the study assessed lesion volume changes and radiation-injury incidence. RESULTS: Data of 850 patients across 14 studies were included in the meta-analysis. The pooled RR of all deep-seated ICMs show a decrease in hemorrhage rate after SRS compared to pre-SRS over the total follow-up period (RR =0.13), initial 2 years (RR =0.22), and after 2 years (RR =0.07). For 9 studies that reported hemorrhage rate of the brainstem only, the pooled RR shows a decrease of hemorrhage rate after SRS compared to pre-SRS over the total follow-up period (RR =0.13), initial 2 years (RR =0.19), and after 2 years (RR =0.07). Volumetric regression was achieved in 44.25% and stability in 56.1%. The pooled incidence of symptomatic and permanent radiation injury was 9% (95% CI, 7-11) and 3% (95% CI, 0-1.9%), respectively. CONCLUSION: SRS appears effective in reducing hemorrhage rates for deep-seated ICMs. The risk of symptomatic radiation injury is low. Given the high risk of surgical morbidity, SRS is a reasonable treatment option for patients with deep-seated ICMs with at least one prior hemorrhage.

Transjugular Intrahepatic Portosystemic Shunt in Nonmalignant Noncirrhotic Portal Vein Thrombosis and Portosinusoidal Vascular Disorder.

Transjugular intrahepatic portosystemic shunt (TIPS) emerges as a key treatment for portal hypertension (PH) complications. While international guidelines provide clear indications for its use in cirrhosis, empirical knowledge is notably scarcer in non-cirrhotic PH, particularly in nonmalignant noncirrhotic portal vein thrombosis (NNPVT) and in patients with portosinusoidal vascular disorder (PSVD). Patients afflicted by these rare diseases exhibit distinct clinical profiles compared to their cirrhotic counterparts, often characterized by a younger age, predominantly preserved hepatic functionality even in cases of severe PH, and a higher propensity for extensive splanchnic thrombosis, which intricately complicates TIPS placement, posing unique challenges for its creation. The objective of this review is to synthesize existing literature on the effectiveness, safety, specific indications, and clinical outcomes of TIPS in adult patients with NNPVT or PSVD, focusing also on the technical challenges of TIPS insertion in the presence of portal cavernoma.

Endoscopic Endonasal Approach to the Orbit: A Case Series and Clinical Experience Emphasizing the Advantages of the Ipsilateral Mononostril Technique.

BACKGROUND: Lesions situated within the orbit pose significant challenges in management due to the confined space they occupy and their proximity to critical anatomical structures. The objective of our study is to assess the feasibility of the ipsilateral endoscopic endonasal approach for orbital cavernous hemangiomas and to comprehend the surgical anatomy of the orbital apex and inferomedial orbital structures. METHODS: Thirteen patients (8 women, 5 men), with ages ranging from 25 to 54 years (mean 35.2 ± 8.3 years), with orbital cavernous hemangioma who underwent surgery via the ipsilateral mononostril endoscopic endonasal approach between August 2018 and August 2023 were retrospectively evaluated. Demographic characteristics, clinical data, radiographic images, and clinical outcomes of the patients were collected from digital medical records. RESULTS: The left orbit was more commonly affected (9 left, 4 right). The average postoperative follow-up duration was 22.2 months (range: 6-50 months). Among the 13 cases of orbital cavernous hemangioma, 1 (7.7%) was located in the extraconal compartment, and 12 (92.3%) were situated in the intraconal compartment. Complete surgical resection of the tumor was successfully achieved in all patients. CONCLUSIONS: Our study highlights the potential advantages of employing a purely ipsilateral mononostril endoscopic endonasal approach for orbital surgery, particularly for accessing the orbital apex and managing medial and inferomedial orbital lesions. This technique holds promise for reducing morbidity and enhancing outcomes, especially when combined with careful patient selection, preoperative planning, and advanced endoscopic skills.

Adhesive arachnoiditis, subarachnoid hemorrhage, and intradural extramedullary thoracic cavernoma: illustrative case.

BACKGROUND: Spinal arachnoiditis can result from various factors, including spinal subarachnoid hemorrhage (sSAH). In this paper, the authors describe a case of intradural extramedullary cavernoma with an initial presentation of subarachnoid hemorrhage leading to multilevel spinal arachnoiditis to discuss the pathophysiology and optimal treatment strategy. OBSERVATIONS: Spinal intradural extramedullary cavernoma manifesting with sSAH is a rare clinical presentation; therefore, there is no clear strategy for the management of sSAH. Spinal arachnoiditis is a result of chronic inflammation of the pia arachnoid layer due to hematomyelia. No effective treatment that interrupts this inflammatory cascade and would also prevent the development of spinal arachnoiditis has been described to date. LESSONS: Lumbar drainage could aid in sSAH management, relieve spinal cord compression, and restore the normal spinal cerebrospinal fluid circulation gradient. It could help to clear the blood degradation products rapidly and prevent early inflammatory arachnoiditis development. Mini-invasive intrathecal endoscopic adhesiolysis appears to be a reasonable approach for reducing the risk of aggravating spinal arachnoiditis with a mechanical-surgical stimulus. Whether a conservative approach should be applied in these patients with mild myelopathy symptoms is still debatable.

Microsurgical Resection for Cavernous Malformation of the Uncus: 3D-Operative Video.

Cavernous malformations (CMs) are rare and often oligosymptomatic vascular lesions. The main symptoms include seizure and focal neurologic deficits.1-3 Depending on the symptomatology, location, size, and risk factors for bleeding, like the presence of a developmental venous anomaly, CMs can be highly morbid. Thus surgical resection may be considered. Deep-seated and eloquent CMs, like those in the uncus, can be challenging.4,5 In Video 1, we present a 23-year-old male adult who developed focal seizures (i.e., oral automatisms) after an episode of sudden intense headache 1 year ago. His neurologic examination was unremarkable. The patient consented to the procedure and publication of his image. Nevertheless, his magnetic resonance images showed an uncal 2-cm Zabramski type I CM. We exposed the insula and its limen through a right pterional craniotomy and transsylvian corridor. During the video, we discuss the surgical nuances to access and resect this CM lesion en bloc while preserving important vascular structures and white matter tracts. Postoperative neuroimaging demonstrated total resection. In postoperative day 1, the patient had 1 episode of generalized seizure and evolved with contralateral hemiparesis. The patient had a good recovery and was discharged on postoperative day 21. At the 6-month follow-up, the patient had no new epileptic events and presented complete weakness improvement. Through this minimally invasive and well-known surgical corridor, we preserve the mesial and lateral portion of the temporal lobe, reducing the risk of lesions to the Meyer loop and limbic association area.

Giant brainstem cavernoma in pediatrics: diagnosis and treatment-case report.

INTRODUCTION: Brain cavernomas or cavernous angiomas are a rare vascular malformation in the general population, even more so in pediatric patients. Their incidence in this group is less than 5% of all vascular malformations. They are typically found in the cerebral hemispheres in cortico-subcortical locations and, more rarely, in the brainstem. OBJECTIVE: To describe the diagnosis, treatment, and follow-up of a case involving a pediatric patient with a giant cavernoma in the brainstem at J.P. Garrahan Hospital. MATERIALS AND METHODS: The clinical history of the case was retrieved from the database of J.P. Garrahan Pediatric Hospital. Additionally, a literature search was conducted in high-impact factor journals using the PubMed database. CONCLUSION: Both the authors of this study and experts consulted through the literature agree that, given the eloquence of the affected area and its challenging accessibility, close monitoring and an expectant approach are advisable for such patients. Nevertheless, when the onset of the case warrants it, surgical intervention is deemed necessary in emergency situations and following the acute phase for complete resolution of the pathology.

Subarachnoid Hemorrhage Caused by Supratentorial Cerebral Cavernous Malformation: A Case Report.

Cavernous malformations (CMs) are acquired vascular abnormalities of the central nervous system that are typically asymptomatic. Clinically symptomatic lesions may present with seizures, intracerebral hemorrhage, or focal neurological deficits. Very rarely, CMs have been described as the cause of subarachnoid hemorrhage. We report a case of a previously healthy 58-year-old man who presented with acute onset of severe headache associated with vomiting. Head computed tomography (CT) scan showed subarachnoid hemorrhage with intraventricular extension. Subsequent CT angiography (CTA) and digital subtraction angiography (DSA) studies showed no evidence of vascular abnormalities. The patient was initially managed conservatively but later required neurosurgical and radiological interventions due to a complicated hospital course and worsening clinical condition. During surgery, an incidental mass was found in the temporal lobe, and subsequent histopathological examination confirmed the diagnosis of cavernoma, which was likely the underlying cause of the subarachnoid hemorrhage. This report highlights the importance of considering CMs in the differential diagnoses of subarachnoid hemorrhage, especially in the absence of informative results from CTA and DSA studies. Timely detection and management of CMs may positively impact the clinical outcome, leading to reduced morbidity and mortality rates.

Occipital Lobe Cavernoma Presenting With Headaches and Visual Hallucinations: A Case Report.

Cavernomas, also known as cavernous angiomas or cavernous malformations, are rare vascular lesions characterized by abnormal clusters of dilated capillaries without intervening brain tissue. While often asymptomatic, they can manifest with neurological symptoms such as headaches, seizures, and focal deficits. We present a case of a 45-year-old male who presented with persistent headaches and visual hallucinations. Thorough clinical assessment revealed intermittent throbbing headaches localized to the left occipital region, accompanied by brief episodes of vivid visual hallucinations. Extensive work-up, including laboratory tests and neuroimaging, identified a subependymal cavernoma in the left occipital lobe. A surgical excision was performed, resulting in sustained relief from headaches and the absence of visual hallucinations during follow-up examinations. This case contributes to the understanding of cavernomas by detailing the clinical presentation, diagnostic process, and successful surgical intervention for a subependymal cavernoma in the left occipital lobe. The resolution of symptoms postoperatively underscores the importance of individualized treatment approaches, considering factors such as lesion location, patient age, and associated risks. The case highlights the evolving knowledge in cavernoma management and emphasizes the need for tailored therapeutic decisions in addressing neurovascular disorders.

Axial Sections of Brainstem Safe Entry Zones and Clinical Importance of Intrinsic Structures: A Review.

Brainstem surgery is more difficult and riskier than surgeries in other parts of the brain due to the high density of critical tracts and cranial nerves nuclei in this region. For this reason, some safe entry zones into the brainstem have been described. The main purpose of this article is to bring on the agenda the significance of the intrinsic structures of the safe entry zones to the brainstem. Having detailed information about anatomic localization of these sensitive structures is important to predict and avoid possible surgical complications. In order to better understand this complex anatomy, we schematically drew the axial sections of the brainstem showing the intrinsic structures at the level of 9 safe entry zones that we used, taking into account basic neuroanatomy books and atlases. Some illustrations are also supported with intraoperative pictures to provide better surgical orientation. The second purpose is to remind surgeons of clinical syndromes that may occur in case of surgical injury to these delicate structures. Advanced techniques such as tractography, neuronavigation, and neuromonitorization should be used in brainstem surgery, but detailed neuroanatomic knowledge about safe entry zones and a meticulous surgery are more important. The axial brainstem sections we have drawn can help young neurosurgeons better understand this complex anatomy.

A small frontal lobe cavernoma presenting with headache mimicking migraine and complex focal seizure: A case report.

Cavernoma, or cerebral cavernous angioma, are hamartomatous lesions formed by sinusoidal vascular spaces without cerebral parenchyma in between. Cavernoma is a rare disorder that is diagnosed infrequently and incidentally, so it is called incidentaloma. However, cavernoma can present with seizures, headaches, and other focal neurological deficits, with seizures being the most frequent presentation. Cavernoma is angiographically concealed, and it's diagnosis is challenging. So, the cavernoma is diagnosed based on an MRI. We present the rare case of a patient who presented with a complex focal seizure and migraine-like headache caused by a small frontal lobe cavernoma.

Acute management of ruptured cavernous malformation of the optic nerve: illustrative case.

BACKGROUND: A cavernous malformation of the optic nerve (CMON) is a rare condition that often presents with an abrupt decline in vision. Acute management of ruptured optic nerve cavernous malformations is generally surgical, although the timing of surgery is controversial. OBSERVATIONS: A 47-year-old female experienced the sudden loss of vision in her left eye. Examination showed that this eye was nearly blind, and her right eye had a temporal field defect. Neuroimaging showed hemorrhage in her left optic nerve and optic chiasm. She was taken to the operating room on an emergent basis where the optic canal was decompressed, the hemorrhage was evacuated, and a vascular malformation with features of a cavernoma was removed from the optic nerve. Over the next 2 days, the vision in her right eye significantly recovered. LESSONS: CMONs remain rare, and it is unlikely that enough cases can be gathered to form a larger trial to compare the role and timing of surgery. On the basis of our experience with this case, the authors recommend that acute CMON-related hematomas should be treated as a surgical emergency and managed with acute optic nerve decompression, hematoma evacuation, and cavernoma resection to improve chances of vision recovery and prevent further vision loss.

Spinal intradural extramedullary cavernoma: A case report.

INTRODUCTION: Cavernomas are rare vascular lesions that can occur anywhere along the neuraxis. However, they are most commonly found in the cerebral hemispheres. Spinal cavernomas are more uncommon and intradural extramedullary cavernomas are the most uncommon as they constitute only 3 % of spinal cavernomas. PRESENTATION: A 36-year-old female presented to our neurosurgical clinic with a history of back pain radiating to the left side of the chest with left lower extremity paresthesia and ataxia without urinary disturbance. Neurological exam showed left-sided hypoesthesia below the T9 dermatome in addition to increased patellar and Achilles reflexes on the left side. MRI showed a homogeneous intradural extramedullary mass which was hyperintense on T1 and hypointense on T2 and it was surgically resected. Pathological examination confirmed the diagnosis of intradural extramedullary cavernoma. DISCUSSION: Intradural extramedullary cavernomas are extremely rare lesions that arise within the area located between the inner surface of the dura and the pial surface of the spinal cord. Up until 2022 only 40 cases of intradural extramedullary cavernomas were reported in the literature. MRI is the preferred imaging modality and pathology is the golden standard for diagnosis. Surgical resection showed very promising results and it is considered the golden standard for treating this condition. However, surgery should be performed urgently to give an optimal outcome. CONCLUSION: Clinicians should consider this condition in their differential diagnoses when faced with progressive spinal root compression symptoms, sudden onset myelopathy, or progressive subarachnoid hemorrhage.

Optochiasmatic Cavernomas: Updated systematic review and proposal of a novel classification with surgical approaches.

Cavernomas are histologically benign vascular malformations found at different sites in the brain. A rare site for such cavernomas, however, is the anterior optic pathway, comprising the optic nerve, chiasma, and optic tract-called optochiasmatic cavernomas (OCC). These lesions usually present with sudden onset or progressive vision loss, headache, and features mimicking pituitary apoplexy. In this paper, we describe a case of OCC operated at our center. We carry out an updated review of literature depicting cases of OCC, their clinical presentation, management, and postoperative complications. We also propose a novel classification system based on lesion location and further analyze these cavernoma types with respect to the surgical approach used and visual outcome. A 30-year-old lady had presented with a 3-week history of progressive bilateral vision loss and headache. Based on imaging, she was suspected to have a cavernous angioma of the chiasma and left optic tract. Due to progressive vision deterioration, the lesion was surgically excised using pterional craniotomy. Postoperatively, her visual symptoms improved, but she developed diabetes insipidus. Clinical and radiological follow-up has been done for 18 months after surgery. A total of 81 cases have been described in the literature, including the present case. Chiasmal apoplexy is the most common presentation. Surgical excision is the standard of care. Our analysis based on lesion location shows the most appropriate surgical approach to be used for each cavernoma type. Visual outcome correlates with the preoperative visual status. Visual outcome is good in patients presenting with acute chiasmal apoplexy, and when complete surgical excision is performed. The endonasal endoscopic approach was found to provide the best visual outcome. In addition to preoperative visual status, complete surgical excision predicts favorable visual outcomes in OCC. Our proposed classification system guides the appropriate surgical approach required for a particular location of the cavernoma.

Hyperintense Perilesional Edema on T1-Weighted Imaging in Cavernoma: A Case Report.

Cavernoma, also called a cavernous malformation, is a vascular malformation that happens during development. It tends to look like a berry-shaped lesion. In cerebral hemorrhagic cavernous malformations (cavernoma), T1-weighted imaging that shows hyperintense perilesional edema in brain masses is an unusual radiological finding. This sign's association with cavernoma is gaining prominence. We present the case of a 35-year-old female patient without significant medical history who reported a seven-day history of left-side weakness that began in the upper limb, progressed to the lower limb, and was associated with nausea. The non-contrast T1- T1-weighted images displayed a gradient of hyperintense content of the lesion with surrounding relatively hyperintense perilesional edema. The patient consequently underwent surgery to evacuate the hematoma and excise the lesion, which went uneventfully.

A taxonomy for superficial cerebral cavernous malformations: subtypes of cortical and subcortical lesions.

OBJECTIVE: A taxonomy for superficial cerebral cavernous malformations (CMs), those based cortically in gyral gray matter or subcortically in underlying white matter, is proposed to build on the comprehensive, systematic characterization of CMs in the entire brain. METHODS: Patients with superficial cerebral CMs were retrospectively analyzed from a consecutive surgical series between November 2008 and June 2021 at the authors' center. Superficial cerebral CMs were categorized into 4 subtypes based on their cortical location or, if subcortical, proximity to the nearest cerebral surface: convexity, medial, basal, and sylvian. Lobar location was also included for subtyping: frontal, temporal, parietal, and occipital. RESULTS: A total of 362 CMs were resected in 346 patients. CM subtypes were as follows: 132 (36.5%) convexity, 78 (21.5%) medial, 72 (19.9%) basal, and 80 (22.1%) sylvian. Frontal CMs were most common (155 [42.8%]), followed by parietal (89 [24.6%]), temporal (87 [24.0%]), and occipital (31 [8.6%]). Of all CMs, 302 (83.4%) were cortical and 60 (16.6%) were subcortical. The mean subcortical depth of deep lesions was 2.97 cm, and the mean lesion volume was 4.68 cm3. Overall, 228 lesions (63.0%) were resected through a transgyral approach, and 134 (37.0%) were resected through a transsulcal approach. Good outcomes (modified Rankin Scale [mRS] score ≤ 2) were observed in 314 patients (86.7%) and poor outcomes (mRS score > 2) in 25 patients (6.9%), and 23 patients (6.4%) were lost to late follow-up (mean follow-up duration 11.5 months). Relative outcomes were good (unchanged or improved mRS score) in 327 patients (90.3%) and poor (worse or died) in 35 patients (9.7%). CONCLUSIONS: Superficial cerebral CMs were resected through a gyrus or sulcus to open the subarachnoid dissection corridors, traversing the full extent of sulci to deepen the approach and minimize tissue transgression. Transgyral dissection avoids associated arteries but is inherently transgressive, whereas transsulcal dissection preserves cortical tissue and may reduce morbidity. Superficial cerebral CMs occupy the largest territory of the 7 types, and the size and surface complexity of the cerebrum make taxonomic subtyping valuable for clear anatomical description.

Olivary body exposure through far lateral and lower retrosigmoid approaches. Comparative analysis of the exposed surface and angle of attack.

OBJECTIVES: Throughout neurosurgical history, the treatment of intrinsic lesions located in the brainstem has been subject of much controversy. The brainstem is the anatomical structure of the central nervous system (CNS) that presents the highest concentration of nuclei and fibers, and its simple manipulation can lead to significant morbidity and mortality. Once one of the safe entry points at the medulla oblongata has been established, we wanted to evaluate the safest approach to the olivary body (the most used safe entry zone on the anterolateral surface of the medulla oblongata). The proposed objective was to evaluate the working channel from the surface of each of the far lateral and retrosigmoid approaches to the olivary body: distances, angles of attack and channel content. MATERIAL AND METHODS: To complete this work, a total of 10 heads injected with red/blue silicone were used. A total of 40 approaches were made in the 10 heads used (20 retrosigmoid and 20 far lateral). After completing the anatomical study and obtaining the data referring to all the approaches performed, it was decided to expand the sample of this research study by using 30 high-definition magnetic resonance imaging of anonymous patients without cranial or cerebral pathology. The reference points used were the same ones defined in the anatomical study. After defining the working channels in each of the approaches, the working distances, angle of attack, exposed surface, and the number of neurovascular structures present in the central trajectory were analyzed. RESULTS: The distances to the cranial and medial region of the olivary body were 52.71 mm (SD 3.59) from the retrosigmoid approach and 27.94 mm (SD 3.99) from the far lateral; to the most basal region of the olivary body, the distances were 49.93 (SD 3.72) from the retrosigmoid approach and 18.1 mm (SD 2.5) from the far lateral. The angle of attack to the caudal region was 19.44° (SD 1.3) for the retrosigmoid approach and 50.97° (SD 8.01) for the far lateral approach; the angle of attack to the cranial region was 20.3° (SD 1.22) for the retrosigmoid and 39.9° (SD 5.12) for the far lateral. Regarding neurovascular structures, the probability of finding an arterial structure is higher for the lateral far, whereas a neural structure will be more likely from a retrosigmoid approach. CONCLUSIONS: As conclusions of this work, we can say that far lateral approach presents more favorable conditions for the microsurgical treatment of intrinsic bulbar and bulbomedullary lesions approached through the caudal half of the olivary body. In those cases of bulbar and pontine-bulbar lesions approached through the cranial half of the olivary body, the retrosigmoid approach can be considered for selected cases.

Extra-Axial Cavernous Angioma: A Case Report and Review of the Literature.

Cavernous angiomas (CAs) are benign vascular malformations predominantly seen in the brain parenchyma and therefore referred to as intra-axial. Extra-axial dural-based cavernous angiomas, on the other hand, are rare vascular lesions found outside of the brain parenchyma. They occur in the middle fossa and may be easily misdiagnosed as meningiomas due to their extra-axial location. In addition, CAs that are located outside the middle fossa, such as in the convexity, have a better prognosis since they are more surgically accessible. Surgical resection is the main treatment of choice in CAs. However, other options, such as embolization and radiotherapy, may also be considered therapeutic choices or additive treatment options. The pathogenesis of CA and the involvement of other factors (genetics or environmental factors) are still unknown and require further investigation. We are presenting a young man who presented for evaluation of seizure-like events without any family history of neurologic conditions. The physical examination was unremarkable except for a slightly antalgic gait. Imaging studies showed an extra-axial left tentorial mass suggestive of a meningioma, hemangiopericytoma, or other extra-axial lesions. The lesion was resected where its vascular nature was mentioned initially, and the histology proved the diagnosis of cavernous angioma. Here we give an overview of the known pathogenesis, causes, clinical features, and diagnostic and therapeutic options in CA. Better knowledge about CA, its causes, clinical features, and treatment options would help clinicians in early diagnosis and patient management.