Incidental optochiasmatic cavernoma: Case report of an unusual finding on 3 Tesla MRI

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.

Magnetic Resonance Imaging of Multiple Cerebral and Spinal Cavernous Malformations of a Patient with Dementia and Tetraparesis

Cavernomas are rare cerebrovascular malformations that usually occur in sporadic forms with solitary lesions located most often in the hemispheric white matter, but also in the infratentorial or spinal region. Multiple lesions at different CNS levels are considered a hallmark for the familial form of the disease. The diagnostic modality of choice for cerebral cavernous malformations (CCMs) is magnetic resonance imaging (MRI). We present an intriguing case of a 65-year-old male admitted to our hospital with tetraparesis and cognitive impairment where highly sensitive MRI sequences identified many cerebral cavernous lesions at the supra-, infratentorial and cervical–thoracic spine levels, some of them with recent signs of bleeding in a patient with oral anticoagulant therapy due to atrial fibrillation. The mechanism of cognitive impairment in this patient is most probably the interruption of strategic white matter tracts, as it is known to happen in other subcortical vascular pathologies. MRI can be helpful not only in mapping the anatomical distribution of lesions, but also in weighing the risks and making decisions regarding whether or not to continue oral anticoagulant therapy.

Cavernous Malformation of the Optic Nerve and Chiasm: Prompt Suspicion and Surgery Matter

BACKGROUND

Cavernous malformations (CMs) of the optic nerve and chiasm are extremely rare, accounting for less than 1% of all intracranial CMs. Acute, subacute, or progressive visual loss from CM may occur with or without hemorrhage. Prompt surgical excision of the CM offers the best hope to improve or stabilize vision. Given its rarity, optic nerve and chiasm CMs may not be readily suspected. We provide 3 cases of optic nerve and chiasm CM, highlighting key neuroimaging features and the importance of expedited intervention.

METHODS

Case records of the neuro-ophthalmology clinics of the Bascom Palmer Eye Institute and the University of Colorado, and literature review of reported cases of optic CM.

RESULTS

A 49-year-old woman reported acute progressive painless vision loss in the right eye. MRI showed a suprasellar mass with heterogeneity in signal involving the right prechiasmatic optic nerve. Surgical excision of the CM 5 days after onset of visual loss improved vision from 20/300 to 20/30. A 29-year-old woman with acute painless blurred vision in the right eye had anterior chiasmal junctional visual field defects corresponding to a heterogeneously minimally enhancing mass with blood products enlarging the optic chiasm and proximal right optic nerve. Surgical excision of the CM 8 weeks after onset of visual loss improved vision from 20/40 to 20/15 with improved visual fields. A 33-year-old woman with a history of familial multiple CMs, diagnosed at age 18, reported new-onset severe headache followed by blurred vision. MRI showed a hemorrhagic lesion of the optic chiasm and right optic tract. She was 20/20 in each eye with a reported left superior homonymous hemianopia. No intervention was recommended. Vision of the right eye worsened to 20/400 2 months later. The patient was followed over 13 years, and the MRI and visual function remained unchanged. Literature review yielded 87 optic CM cases occurring across gender and nearly all ages with visual loss and headache as the most common presenting symptoms. Optic chiasm is the most common site of involvement (79%). Nearly 95% of reported CM cases were treated with surgery with 81% with improved vision and 1% with worsened vision.

CONCLUSION

MRI features are critical to the diagnosis of optic nerve and chiasm CM and may mimic other lesions. A high index of suspicion by the neuro-ophthalmologist and neuroradiologist leads to early recognition and intervention. Given optic CM displaces and does not infiltrate neural tissue, expedited surgical resection by a neurosurgeon after consideration of other diagnostic possibilities improves visual function in most cases.

An isolated cavernous malformation of the sixth cranial nerve: A case report and review of literature

Background

Isolated cavernous malformation (CM) of the abducens nerve has not been reported in the literature. Herein, the authors address the clinical importance of these lesions and review the reported cases of CM from 2014 to 2020.

Case Description

A 21-year-old man presented with binocular diplopia and headache from 2 months before his admission. The neurological examination revealed right-sided abducens nerve palsy. The brain MRI revealed an extra-axial pontomedullary lesion suggestive of a CM. The lesion was surgically removed. During the operation, the abducens nerve was resected considering the lesion could not be separated from the nerve and an anastomosis was performed using an interposition nerve graft and fibrin glue. Pathological examination of the resected lesion revealed that it was originated from within the nerve. The patient's condition improved in postoperative follow-ups.

Conclusion

Surgical resection of the cranial nerves CMs is appropriate when progressive neurological deficits are present. If the lesion is originated from within the nerve, we suggest resection of the involved nerve and performing anastomosis. Novel MRI sequences might help surgeons to be prepared for such cases and fibrin glue can serve as an appropriate tool to perform anastomosis when end-to-end sutures are impossible to perform.

Cavernous Malformations of the Optic Nerve and Optic Pathway: A Case Series and Systematic Review of the Literature

BACKGROUND

Although rare, cavernous malformations (CMs) of the optic nerve and anterior optic pathway (optic pathway cavernous malformations [OPCMs]) can occur, as described in several single case reports in the literature.

OBJECTIVE

To describe the technical aspects of microsurgical management of CMs of the optic pathway on the basis of an extensive single-center experience and review of the literature.

METHODS

A systematic literature review was performed to augment an earlier review, using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In addition, an institutional database was searched for all patients undergoing surgical resection of OPCMs. Patient information, surgical technique, and clinical and radiographic outcomes were assessed.

RESULTS

Since the previous report, 14 CMs were resected at this institution or by the senior author at another institution. In addition, 34 cases were identified in the literature since the systematic review in 2015, including some earlier cases that were not discussed in the previous report. Most OPCMs were resected via pterional, orbital-pterional, and orbitozygomatic craniotomies. Visual outcomes were similar to those in earlier reports, with 70% of patients reporting stable to normal vision postoperatively.

CONCLUSION

OPCMs can occur throughout the anterior visual pathway and may cause significant symptoms. Surgery is feasible and should be considered for OPCMs presenting to a surface of the nerve. Favorable results can be obtained with resection, although optimal results are obtained with patients who present with milder symptoms without longstanding damage to the optic apparatus.

Opto-chiasmatic apoplexy as a compartment syndrome? Anatomical and surgical considerations on two bleeding cavernous malformations

OBJECTIVE

Opto-chiasmatic (OC) cavernous malformations are sporadic lesions that are often misdiagnosed clinically and radiologically. Presenting symptoms range from incidental findings to the more frequent and dramatic "chiasmal apoplexy." The present study aims to evaluate the potential role of arachnoidal membranes of the basal cisterns in the onset of OC apoplexy. A possible mechanism resembling a compartment syndrome is discussed through the description of two cases of bleeding cavernomas.

METHODS

We describe clinical, radiological, intraoperative findings in two cases of young patients presenting with OC apoplexy from bleeding cavernoma. The first was a 38-year-old man diagnosed with optic neuritis at the first episode of visual acuity deterioration. The second patient was a 22 -year-old woman who suffered two OC apoplexy episodes from a recurrence, which also presented with bleeding.

RESULTS

Both patients were operated on via pterional craniotomy and presented a postoperative improvement of visual symptoms. The second patient experienced deterioration 30 months after surgical resection due to rebleeding from a recurrence and required a second operation. Follow-up revealed a good recovery of visual disturbances; MRI at 6 and 3 years showed in both patients an apparent complete removal of the cavernous malformations.

CONCLUSION

The cisternal environment where OC cavernous malformations develop and the paradigm of a compartment syndrome could explain the clinical presentation variability. This very rare subset of cavernomas would benefit from a classification system using ad hoc neuroimaging protocols and consistent indications.

Postoperative Management of Anterior Visual Pathway Cavernoma, a Unique Perspective: Case Report

Cavernous malformations (CMs) are low-flow vascular lesions with an incidence of 0.1% to 0.7% in the general population. Less than 1% are found in the anterior visual pathway. The most common presenting symptoms are visual disturbances due to hemorrhage and the current standard of treatment is gross total resection.

The authors report a case of a 42-year-old male with visual disturbance and findings on T1-weighted magnetic resonance imaging (MRI) suggesting CM of the right optic nerve and right optic chiasm. The patient underwent right pterional craniotomy for gross total resection of the lesion. One year postoperatively, the patient demonstrated improvement in visual deficits with no signs of recurrence on MRI. Thirty-two months postresection, MRI showed a small slightly lobulated area of T1 hyperintense material within the postoperative cavity along the right aspect of the optic chiasm. MRI at 39 months postresection showed previously seen small amounts of T1 hyperintensity in the central and right aspect of the optic chiasm, with significantly decreased conspicuity. These findings suggest a trace amount of recurrence in the 32-month postoperative imaging despite overall stable visual field testing.

There is a paucity of literature concerning the retreatment of resected CM in the anterior visual pathway. The authors suggest serial imaging as an integral component of CM management. Although repeated visual field testing and clinical follow-up are important aspects of CM management, they are no substitute for the gold standard of MRI.