Case report: Delayed outflow obstruction of a DVA: A rare complication of brainstem cavernoma surgery

Introduction

Developmental venous anomalies (DVAs) are considered variants of normal transmedullary veins. Their association with cavernous malformations is reported to increase the risk of hemorrhage. Expert consensus recommends meticulous planning with MR imaging, use of anatomical “safe zones”, intraoperative monitoring of long tracts and cranial nerve nuclei, and preservation of the DVA as key to avoiding complications in brainstem cavernoma microsurgery. Symptomatic outflow restriction of DVA is rare, with the few reported cases in the literature restricted to DVAs in the supratentorial compartment.

Case

We present a case report of the resection of a pontine cavernoma complicated by delayed outflow obstruction of the associated DVA. A female patient in her 20's presented with progressive left-sided hemisensory disturbance and mild hemiparesis. MRI revealed two pontine cavernomas associated with interconnected DVA and hematoma. The symptomatic cavernoma was resected via the infrafacial corridor. Despite the preservation of the DVA, the patient developed delayed deterioration secondary to venous hemorrhagic infarction. We discuss the imaging and surgical anatomy pertinent to brainstem cavernoma surgery, as well as the literature exploring the management of symptomatic infratentorial DVA occlusion.

Conclusion

Delayed symptomatic pontine venous congestive edema is extremely rare following cavernoma surgery. DVA outflow restriction from a post-operative cavity, intraoperative manipulation, and intrinsic hypercoagulability from COVID-10 infection are potential pathophysiological factors. Improved knowledge of DVAs, brainstem venous anatomy, and “safe entry zones” will further elucidate the etiology of and the efficacious treatment for this complication.

Cerebral arteriovenous malformation and foreign accent syndrome: a case report

OBJECTIVE

This case study aims to present the Foreign Accent Syndrome (FAS) in a patient with Cerebral Arteriovenous Malformation (cAVM), considering neuropsychological, radiological and microsurgical aspects.

METHODS

The patient underwent preoperative neuropsychological assessment and MRI and Tractography were performed to identify fibers close to the lesion site. In the surgical procedure, a craniotomy was performed for excision of the cAVM. After surgery and 6 months after the surgical procedure, the patient underwent further and neuropsychological evaluations.

RESULTS

The presence of AVM located in the posterior part of the medial surface of the left superior frontal gyrus was identified and the neuropsychological evaluation found cognitive deficits and symptoms characteristic of FAS, which disappeared after resection.

CONCLUSION

This report presented a case of cAVM in which symptoms were found even without rupture, which was no longer observed after the surgical procedure, demonstrating the relationship of cAVM with the symptoms and neuroanatomical bases of FAS.

Awake Microsurgical Resection for a Precentral Gyrus Arteriovenous Malformation-Three-Dimensional Video and Anatomic Landmarks

Arteriovenous malformations (AVMs) are complex, heterogeneous, and uncommon neurovascular disorders that frequently manifest in young adults. Parenchymal AVMs are thought to be congenital, but this has been recently questioned in the literature.^1,2 AVMs can change over time and cause focal neurological signs or neurocognitive deficits.³ The clinical presentation of an AVM is variable and depends mainly on the occurrence of bleeding as well as its location, size, and ability to take flow from adjacent areas.⁴ AVMs can be treated by a single modality or a combination of different modalities. According to the Expert Consensus on the Management of Brain Arteriovenous Malformations, neurosurgery may be the best option for Spetzler-Martin grade 2 AVMs.⁵ However, the treatment of these lesions when located in eloquent areas, especially in the central lobe, is controversial. Awake craniotomy allows identification of eloquent gyrus and can potentially facilitate resection with functional preservation. An alternative is stereotactic radiosurgery, but a qualitative comparative analysis revealed higher obliteration rate with awake AVM excision compared with stereotactic radiosurgery.⁶ Awake craniotomy was the earliest surgical procedure known, and it has become fashionable again. It was used in the past for surgical management of intractable epilepsy, but its indications are increasing, and it is a widely recognized technique for resection of mass lesions involving the eloquent cortex and for deep brain stimulation.⁷ Its application for resection of vascular lesions, including AVMs, is still limited. In the Video, we present a case of a cerebral AVM of the precentral gyrus in which we achieved complete resection with awake microsurgical treatment without any neurological sequelae for the patient.

Microsurgery for a medial left giant lesser sphenoid wing meningioma complicated by postoperative vasospasm of the ipsilateral supraclinoid carotid artery

Background:

Sphenoid wing meningiomas present close contact with intracranial arteries and have great potential for vascular complications. Here, we describe the case of a patient who presented a medial left giant lesser sphenoid wing meningioma involving the supraclinoid carotid artery. One week after surgery, she developed vasospasm whose treatment using milrinone achieved excellent results.

Case Description:

This is the case of a 23-year-old female with a large meningioma of the middle third of the lesser wing of the left sphenoid. Furthermore, the patient had symptoms of headache, diplopia, and left amaurosis (Video 1). The lesion involved the supraclinoid left carotid artery, causing significant stenosis of the vessel. The patient underwent surgical treatment without complications. One week after the procedure, she evolved with lowered level of consciousness, complete, and proportionate right hemiparesis and right Babinski’s sign. Angiographic study demonstrated significant stenosis of the left supraclinoid artery. After endovascular treatment with milrinone, the patient evolved with immediate improvement of signs and symptoms.

Conclusion:

Giant meningiomas with vascular involvement involve a higher risk of postoperative vascular complications. Other studies should be carried out to predict these complications and thus develop preventive measures.

Awake Microsurgical Resection for Optochiasmatic Cavernous Malformation

Cavernous malformations (CM) affect approximately 0.5% of the population, with only a limited portion being located in the optic nerve and chiasma. The clinical presentation is determined by their locations. In the optochiasmatic CM, the acute visual disturbance is the most common presentation. Chronically, many show a progressive visual loss, chronic headache, and pituitary disturbances. The differential diagnosis includes optic glioma, arteriovenous malformations, aneurysm, craniopharyngioma, pituitary apoplexy, and inflammatory conditions. In Video 1, we present the case of a 39-year-old woman with a history of a hemorrhagic optochiasmatic cavernoma in 2016, who started using propranolol to reduce the lesion and symptoms of visual loss. Moreover, the first microsurgical resection of the cavernoma and evacuation of the hematoma were performed in the same year. Owing to evolvement from a partial to a total vision loss in the left eye and presentation of new symptoms in the right eye, the patient underwent microsurgical resection. The surgery was performed sequentially. An awake craniotomy was performed to monitor the chiasma and right optic nerve. The postoperative magnetic resonance imaging showed complete resection of the CM, and the patient fully recovered. The patient signed the institutional consent form, stating that he or she accepts the procedure and allows the use of his or her images and videos for any type of medical publications in conferences and/or scientific articles.

Microsurgical Treatment for Posthemorrhagic Cavernoma of Frontal Lobe Coexisting with Unruptured Ipsilateral Middle Cerebral Artery Aneurysm

Cerebral cavernous malformations, also known as cavernomas, are vascular abnormalities of the brain that are clinically associated with a variety of neurologic symptoms that may include hemorrhagic strokes. They are the most common vascular abnormality, representing 10%-25% of all vascular malformations.¹ Lesions associated with cavernomas include developmental venous anomalies, capillary telangiectasias, and other vascular malformations² but not intracranial aneurysms. The latter association is extremely rare; in fact, there is only 1 case reported in the literature, in which the cavernoma was obscured by the presence of a cerebral hemorrhage and an unruptured aneurysm, which was presumed to be the primary cause of the bleeding, thereby misleading the surgeons to treat only the aneurysm.² There are different alternatives for the management of different types of lesions.^3-5 In this 3-dimensional operative video (Video 1), we present a case of a cavernoma associated with hemorrhage coexisting with an unruptured aneurysm in which we achieved complete resolution of both with microsurgical treatment through a pterional approach.⁶ The patient consented to publication of images.

Transtentorial Approach for Parahippocampal Gyrus Arteriovenous Malformation Resection: 3-Dimensional Operative Video

Medial temporal basal arteriovenous malformations (AVMs) have complex anatomy. They usually drain to the basal vein of Rosenthal, and arterial feeders can arise from the anterior choroidal artery and its branches, or from the posterior cerebral artery. If the AVM is more posterior in the parahippocampal gyrus, there is a predominance of arterial feeders arising from P2P or P3 segments of the posterior cerebral artery. As posterior AVMs are difficult to reach using anterior approaches, the supracerebellar transtentorial approach provides a direct pathway to the malformation, allowing better visualization and exposure of the vascular anatomy.  In this video, we present a 29-yr-old woman with a left parahippocampal AVM with P2P arterial feeders and Rosenthal basal vein drainage. The patient had three months of moderate headache and two abrupt seizures before admission. Emergency computed tomography showed intraventricular hemorrhage. Magnetic resonance imaging and cerebral angiography revealed an AVM located in the parahippocampal gyrus, posterior to pulvinar thalamus. The patient underwent microsurgical treatment in semi-sitting position using a supracerebellar and infratentorial approach with transtentorial resection. The AVM was completely removed, and the patient recovered without neurological deficits. The authors present a 3-dimensional video of the microsurgical steps required to perform a transtentorial approach for AVM resection in the parahippocampal gyrus.  The patient signed the Institutional Consent Form, which allows the use of his/her images and videos for any type of medical publications in conferences and/or scientific articles.

Awake Craniotomy for Removal of Left Insular Cavernous Malformation

The insula plays a crucial role in speech planning due to its connections with cortical and subcortical areas. Surgical management of cavernous malformation (CM) of the insula consists of total resection of the lesion and the surrounding gliosis to avoid or reduce seizures. When located in the dominant hemisphere, an awake craniotomy with intraoperative mapping reduces the risk of functional damage. The insula is covered by the operculum and has a relationship with the middle cerebral artery and its branches that run along its lateral surface. Therefore high expertise is required to manage the exposure of the insula and its complex anatomy. This video demonstrates the surgical management of a large left insular CM. A 29-year-old female with multiple CM and 7 years of partial seizures and recent onset of short memory loss. Neuroimaging showed a large left insular and planum polare CM with important mass effect and hemorrhage signs. The patient consented to surgery, and an awake pretemporal craniotomy was carried out with continuous motor evoked potential monitoring. No language function was localized in the superior temporal gyrus; therefore corticectomy of the middle portion was performed to expand the operative corridor. The vessel manipulation during wide opening of the sylvian fissure increased the risk of postoperative vasospasm and blood drain into the surgical field. The CM was exposed and completely removed without functional damage. The patient recovered from surgery without complications, and no seizures occurred at 2 months' follow-up. Postoperative imaging showed complete removal of the CM.

Orbitozygomatic craniotomy in three pieces: tips and tricks

OBJECTIVE

Didactically describe the orbitozygomatic craniotomy made in three pieces.

METHOD

This approach was performed, from 2002 to 2011, in 49 patients admitted at Beneficência Portuguesa of São Paulo Hospital.

RESULTS

Twenty-seven patients had vascular lesions and twenty-two suffered for intracranial skull base tumors. The vascular lesions varied from cavernous angiomas inside the mesencephalum, high bifurcation basilar tip aneurysms, superior cerebellar arteries aneurysms and arteriovenous malformations in the interpeduncular cistern. Skull base tumors as meningiomas, interpeduncular hamartomas and third ventricle floor gliomas were among the neoplastic lesions approached. We had no permanent injuries and minimal transient complications had occurred.

CONCLUSION

It is a descriptive text, organized in the sequence of the main stages in which such a craniotomy is performed, describing in details the technique in which this group of evolutionarily authors came to accomplish the task.

Pretemporal craniotomy

This paper aims to describe the performance of the pretemporal craniotomy performed didactically from 2002 to 2012 in eighty patients. It is therefore a fundamentally descriptive text, organized in the sequence of the main stages in which such a craniotomy is performed, and describing in detail the technique with which this group of evolutionarily authors came to accomplish the task.

The pterional craniotomy: tips and tricks

This review intended to describe in a didactic and practical manner the frontotemporosphenoidal craniotomy, which is usually known as pterional craniotomy and constitute the cranial approach mostly utilized in the modern neurosurgery. This is, then, basically a descriptive text, divided according to the main stages involved in this procedure, and describes with details how the authors currently perform this craniotomy.

Giant cavernoma of the orbit: clinical and surgical considerations

Cavernous hemangiomas of the orbit are benign, hamartomatous, vascular lesions, more frequent in middle-aged women, representing the most common benign primitive neoplasm of the orbit. Several therapeutic modalities and surgical approaches have been described, in order to preserve the normal orbital structures. We describe the case of a patient with a volumous orbital cavernoma, approached by a fronto-orbito-zigotomy. A review on diagnostic modalities and surgical approaches is also presented.