Surgical Management of Trigeminal Neuralgia Induced by Brainstem Infarct: A Systematic Review of the Literature.

BACKGROUND: Although cases of trigeminal neuralgia (TN) induced by brainstem infarct have been reported, the neurosurgical literature lacks a comprehensive review for this subpopulation of patients. We present the first systematic review of the literature to discuss pathology, surgical management, and future directions for therapeutic innovation in this population. METHODS: Our systematic review was conducted according to PRISMA guidelines. Resulting articles were screened for those that presented cases of TN associated with brainstem infarct. RESULTS: A review of the literature identified 18 case reports of 21 patients with TN induced by brainstem infarct: 14 pontine infarcts and 7 medullary infarcts. Although many cases of ischemic brainstem lesions are caused by acute stroke, cerebral small vessel disease also plays a role in certain cases, and the relationship between these chronic lesions and TN is more likely to be overlooked. Furthermore, we found that reports of self-resolving TN pain after brainstem infarct is disproportionately biased, as most case reports published their data within the first few months after initial presentation. Reports with follow-up periods >13 months reported eventual pain recurrence that necessitated surgical intervention. Microvascular decompression was not sufficient to treat TN pain associated with concurrent neurovascular compression and brainstem infarct. CONCLUSIONS: Brainstem infarcts affecting the trigeminal pathway represent an understudied pathologic cause of TN. Although the neurosurgical literature lacks a clear picture of the most efficacious interventions in this population, we are optimistic that this review will encourage further investigation into the best treatment for these patients.

Association of pretreatment pontine infarction with extremely poor outcome after endovascular thrombectomy in acute basilar artery occlusion.

BACKGROUND: The association between pretreatment brain stem infarction and thrombectomy outcomes remains to be elucidated in patients with acute basilar artery occlusion (BAO). We aimed to assess the association between pretreatment pontine infarction and extremely poor outcome in patients who underwent endovascular thrombectomy due to acute BAO. METHODS: We retrospectively reviewed data from a stroke database to identify patients with acute BAO who underwent thrombectomy between January 2011 and August 2019. Patient characteristics, pretreatment diffusion-weighted imaging (DWI) data, and outcomes were evaluated. The largest infarct core was expressed as the percentage of infarct core area in each brain stem region on the DWI slice displaying the largest lesion. Extremely poor outcome was defined as a 90-day modified Rankin Scale score of 5 or 6. RESULTS: A total of 113 patients were included, 37 of whom had extremely poor outcome. Among the 15 patients with extensive pontine infarction (largest pontine infarct core of ≥70%), 93.3% had extremely poor outcome. Multivariate logistic regression analysis revealed that the following variables were independent predictors of extremely poor outcome: extensive pontine infarction (adjusted OR 22.494; 95% CI 2.335 to 216.689; p=0.007), posterior circulation ASPECTS on DWI (adjusted OR per 1-point decrease 1.744; 95% CI 1.197 to 2.541; p=0.004), age (adjusted OR per 1-year increase 1.067; 95% CI 1.009 to 1.128; p=0.023), and baseline NIHSS (adjusted OR per 1-point increase 1.105; 95% CI 1.004 to 1.216; p=0.040). CONCLUSION: Our results showed that a large pontine infarct core of ≥70% on pretreatment DWI was strongly associated with extremely poor outcome among patients treated with endovascular thrombectomy for acute BAO.

What is the risk of venous cerebellar infarction in the supracerebellar infratentorial approach?

The supracerebellar infratentorial approach (SCITA) is a standard approach used in a neurosurgical practice. It carries some risk of associated complications including cerebellar venous infarction with possible serious sequelae. The objective of this study is to address the incidence of cerebellar venous infarction in SCITA. A search through the currently available literature was performed in September 2019 from the year 2000 until September 2019 dealing with 'supracerebellar infratentorial approach'. Out of the 578 patients found in thirteen case series, two venous infarctions were present; the remaining four patients were published as case reports. By analysing the case series, we calculated the risk of such a complication to be 0.345% (95% CI [0.061%, 1.248%]). Case reports were not included. The real risk is estimated to be higher. The risk of cerebellar venous infarction is an unpredictable, infrequent but real complication with potentially dreadful sequelae. Each neurosurgeon using this approach should be aware of this event when employing this approach. The avoidance of cerebellar venous infarction can be lowered by leaving as many bridging veins intact as possible.

Predicting Surgical Intervention in Cerebellar Stroke: A Quantitative Retrospective Analysis.

BACKGROUND: Debate still exists regarding whether preventive surgical decompression should be offered to high-risk patients experiencing cerebellar stroke. This study aimed to predict neurologic decline based on risk factors, volumetric analysis, and imaging characteristics. METHODS: This retrospective cohort study comprised patients ≥18 years who presented with acute cerebellar ischemic stroke (CIS) between January 2011 and December 2016. Diagnostic imaging was used to calculate metrics based on individual stroke, cerebellar, and posterior fossa volumes. Head computed tomography scans on presentation and day of peak swelling were used to tabulate a CIS score. RESULTS: The study included 86 patients; most were male and African American. Posterior inferior communicating artery stroke was most common (50%). On initial presentation imaging, 18.6% had documented hydrocephalus, 20.9% had brainstem compression, 22.1% had brainstem stroke, and 39.5% had stroke in another vascular territory. Cardioembolic stroke was the most common etiology, followed by cryptogenic stroke. Overall, patients who underwent surgical intervention had larger stroke volumes on presentation. Patients undergoing surgical intervention also experienced faster cerebellar swelling compared with patients without intervention. Total CIS scores were statistically significant and remained significant on the peak day of swelling. CIS score was independently associated with neurosurgical intervention; patients in this group with delayed interventions (median CIS score, 6; range, 4-8) later deteriorated and required emergent surgical decompression. Eleven patients without intervention had CIS score >6; 4 patients died of stroke complications. CONCLUSIONS: Volumetric studies and CIS score are objective measures that may help predict decline on imaging before clinical deterioration.

Superficial Temporal Artery-Superior Cerebellar Artery Bypass with Anterior Petrosectomy.

BACKGROUND: Superficial temporal artery (STA) to superior cerebellar artery (SCA) bypass is associated with a relatively high risk of surgical complications, such as hematoma and/or edema caused by temporal lobe retraction. Therefore, the right side is typically used to avoid retraction of the left temporal lobe. In this report, we present a case of left STA-SCA bypass with anterior petrosectomy to avoid retraction of dominant-side temporal lobe and describe the surgical technique in detail. CASE DESCRIPTION: A 69-year-old man presented with gradual worsening of dysarthria and gait disturbance. Magnetic resonance imaging showed no signs of acute infarction, but digital subtraction angiography showed severe stenosis of basilar artery and faint flow in the distal basilar artery. On 3-dimensional computed tomography angiography, posterior communicating arteries were not visualized; we could identify the left SCA, but not the right SCA. Despite dual antiplatelet therapy, a small fresh brainstem infarct was detected 10 days after admission. To avert fatal brainstem infarction and further enlargement of the infarct, we performed left STA-SCA bypass with anterior petrosectomy to avoid retraction of the dominant-side temporal lobe. Postoperative imaging revealed no new lesions, such as infarction or temporal lobe contusional hematoma, and confirmed the patency of the bypass. Postoperative single-photon emission computed tomography demonstrated improved cerebral blood flow in the posterior circulation. The patient was transferred to another hospital for rehabilitation. CONCLUSIONS: This method helps minimize the risk of injury to the temporal lobe, especially that of the dominant side.

Posterior circulation hyperperfusion syndrome after superficial temporal artery-superior cerebellar artery bypass for vertebral artery dissection.

A 68-year-old man was diagnosed with infarction of the cerebellum and medulla oblongata caused by vertebral artery dissection manifesting as severe stenosis with poor collateral flow. He underwent superficial temporal artery (STA)-superior cerebellar artery (SCA) bypass for the prevention of fatal brain stem infarction. He had consciousness disturbance 2 days postoperatively. Single-photon emission computed tomography revealed hyperperfusion in the posterior circulation. His consciousness improved as hyperperfusion improved. We report the first case of posterior circulation hyperperfusion syndrome after STA-SCA bypass and provide a review of the relevant literature.

Surgical management of vertebral and basilar artery aneurysms: a single center experience in 41 patients.

OBJECTIVE: To study an effective method for surgical management of vertebral and basilar artery aneurysms. METHODS: Forty-one patients with 43 aneurysms of the vertebral and basilar arteries were managed by microsurgical clipping. Cerebral angiography revealed basilar apex aneurysms in 17 patients, basilar trunk in six patients, vertebrobasilar (VB) junction aneurysms in three patients and vertebral aneurysms in 15 patients. One patient had two basilar aneurysms, and another had bilateral vertebral artery aneurysm. SURGICAL TECHNIQUE: We used a pterional approach in basilar apex aneurysms (n = 17 patients), orbitozygomatic and its variants in upper basilar trunk aneurysms (n = 2 patients), combined petrosal and far-lateral approach in mid basilar trunk aneurysms (n = 4 patients), far-lateral and transcondylar approach for the aneurysms at VB junction (n = 3 patients) and transcondylar approach for the vertebral aneurysms (n = 15 patients). Bypass graft was performed in 14 patients with fusiform and wide neck aneurysms, to prevent potential cerebral ischemia due to prolonged temporary occlusion or possibility of intraoperative parent artery sacrifice. RESULTS: Neurological outcomes were measured on the basis of Glasgow Outcome Score (GOS). The rate of back-to-normal life after surgery in basilar tip aneurysm, basilar trunk aneurysms, VB junction aneurysms and vertebral artery aneurysms was 15/17 (82.5 %), 5/6 (83 %), 3/3 (100 %) and 14/15 (93.3 %), respectively. Thirty-six (87.8 %) patients had uneventful postoperative courses. Two patient with basilar apex aneurysm suffered severe neurological deficits related to midbrain ischemia, two patient with occipital artery (OA) graft bypass had postoperative partial lower cranial nerve palsy, and one death with basilar trunk aneurysm occurred after the 20th day of surgery. Thirty-nine patients accepted postoperative digital subtraction angiography (DSA) and eight patients accepted computed tomography (CT) angiogram, whereas two patient denied either one. All the images demonstrated afferent and efferent vessels without aneurysm in situ. Out of 14 patients with graft bypass, 11 patients on cerebral angiographies disclosed the aneurysm clip and the graft bypass patency, one patient on angiography had unidentified graft bypass patency but no symptom related to the graft bypass patency, and two patients denied the postoperative cerebral angiographies. In 40 patients with a mean follow-up of 3.4 years, 37 patients had good outcome, two patients needed assistance for daily living, and one death occurred due to brainstem infarction related to surgery. CONCLUSION: Selection of proper cranial base approach with adequate exposure is effective in clipping VB aneurysms, minimizing the postoperative complications. Graft bypass may avoid parent artery sacrifice and its branches occlusion in patients with fusiform and wide neck aneurysms.

Brainstem cavernous malformations: 1390 surgical cases from the literature.

OBJECTIVE: Although surgical resection of brainstem cavernous malformations (CM) has been reviewed, numerous large surgical series have been recently reported. METHODS: Eighteen new surgical series with 710 patients were found via a PubMed search, in addition to our previous meta-analysis. Complete excision, complications, and long-term outcome results were compiled across these series. They were then compared and subsequently combined with those of our previous report. RESULTS: We combined results of 68 surgical series with 1390 patients, incorporating results from our previous meta-analysis. Across 61 series, 1178 of 1291 (91%) CMs were completely excised. Of 105 partially resected CMs with ample follow-up, 65 rebled (62%). Across 46 series providing information on early neurologic morbidity, the overall rate was 45%. Specifically, 12% of patients required tracheostomy and/or gastrostomy procedures. Overall long-term condition was improved in 62% of patients across 51 series. Across 60 series, overall long-term condition was improved or the same in 84% of patients, with worsening in the remaining 16%. The overall surgical and/or cavernoma related mortality rate for all 1390 patients was 1.5%. Notably, these results did not differ significantly between our initial review and the combined data from the subsequent 18 surgical series recently reported in the literature. CONCLUSION: Surgical resection of brainstem CM continues to present a considerable challenge with resultant morbidity akin to another CM hemorrhage. We therefore prefer to offer surgery only to patients with at least one previous hemorrhage with CM pial representation. Appropriate patient counseling about expected early morbidity and the potential for long-term worsening is crucial.

Simultaneous unilateral internal carotid artery and occlusive basilar artery dissections.

We report a case of brain stem infarction. The case is interesting for simultaneous occurrence of basilar artery (BA) occlusion caused by BA dissection and left internal carotid artery (ICA) dissection after a minor cervical trauma. Stents were implanted at the ICA dissection, and BA occlusion was treated conservatively.

Long-term outcome after suboccipital decompressive craniectomy for malignant cerebellar infarction.

BACKGROUND AND PURPOSE: Suboccipital decompressive craniectomy (SDC) is a life-saving intervention for patients with malignant cerebellar infarction. However, long-term outcome has not been systematically analyzed. METHODS: In this monocentric retrospective study we analyzed mortality, long-term functional outcome, and quality of life of all consecutive patients that were treated by SDC for malignant cerebellar infarction in our institution between 1995 and 2006. RESULTS: A total of 57 patients were identified. All of them were treated by bilateral SDC. An external ventricular drainage was inserted in 82%, necrotic tissue was evacuated in 56% of patients. There were no fatal procedural complications. Five patients were lost for follow-up. In the remaining 52 patients, the mean follow-up interval was 4.7 years (1 to 11 years). Within the first 6 months after surgery 16 of 57 patients (28%) had died. At follow-up, 21 of 52 patients (40%) had died and 4 patients (8%) lived with major disability (mRS 4 or 5). Twenty-one patients (40%) lived functionally independent (mRS 0 to 2). The presence of additional brain stem infarction was associated with poor outcome (mRS > or =4; hazard ratio: 9.1; P=0.001). Quality of life in survivors was moderately lower than in healthy controls. CONCLUSIONS: SDC is a safe procedure in patients with malignant cerebellar infarction. Infarct- but not procedure-related early mortality is substantial. Long-term outcome in survivors is acceptable, particularly in the absence of brain stem infarction.

Staged escalation therapy in acute basilar artery occlusion: intravenous thrombolysis and on-demand consecutive endovascular mechanical thrombectomy: preliminary experience in 16 patients.

BACKGROUND AND PURPOSE: The prognosis of acute basilar artery occlusion (BAO) is poor if early recanalization is not achieved. Recanalization strategies include intravenous thrombolysis (IVT) and intra-arterial thrombolysis, as well as endovascular mechanical thrombectomy (EMT). The combination of IVT with consecutive on-demand EMT may allow for early treatment initiation with high recanalization rates but has never been systematically tested in patients with BAO. METHODS: Starting in January 2006, we treated all eligible patients with acute BAO admitted to our academic stroke center or one of our cooperating community hospitals after a standardized protocol combining IVT with consecutive on-demand EMT. Inclusion criteria were: (1) presence of predefined symptoms clearly suggestive of BAO; (2) exclusion of intracerebral hemorrhage on CT scan; (3) evidence of BAO on CT angiography; (4) start of therapy within 6 hours after symptom onset; and (5) no contraindications for IVT. If CT angiography showed persistent BAO after IVT, EMT was performed. RESULTS: Since January 2006, 16 patients have been treated. All patients received IVT; in 7 of them, EMT became necessary because of persistent BAO. Final recanalization was achieved in 15 patients. Three months after therapy, 12 of 16 patients were still alive; 7 of them had a good outcome (modified Rankin score

Endoscopic third ventriculostomy for occlusive hydrocephalus caused by cerebellar infarction.

OBJECTIVE: The surgical management of occlusive hydrocephalus caused by massive cerebellar infarction remains controversial. The procedures that are more commonly used to avoid progressive neurological deterioration are based on transient external ventricular drainage or the placement of permanent shunt systems. To our knowledge, this is the first report regarding using endoscopic third ventriculostomy (ETV) in patients with an occlusive hydrocephalus caused by cerebellar ischemic stroke. We report our experience of 10 reviewed cases. METHODS: Between 1997 and 2004, 10 patients with a resulting hydrocephalus caused by a space-occupying cerebellar infarction were managed with ETV. Glasgow Coma Scale score on admission, cause of stroke, and computed tomographic signs, including the ischemic vascular territory involved and brain edema, were noted. Clinical outcome was evaluated using the Glasgow Outcome Scale. RESULTS: In all patients, there was a mean interval of 4 days from the onset of deterioration of consciousness to operation. Mean Glasgow Coma Scale score on admission was 11.2. In nine patients, ETV was the initial procedure of ventricular drainage. One patient was primarily treated with an external ventricular drainage, but the device dislocated and ETV was performed. In one patient, an external ventricular drainage became necessary 7 days after the initial ETV because of a malfunction of the stoma. One patient showed a progressive brain edema 2 days after ETV, and suboccipital decompression was performed. Eight successfully treated patients demonstrated an improvement in the level of consciousness after ETV. Mean Glasgow Outcome Scale score on discharge of all patients was 3.4. CONCLUSION: Occlusive hydrocephalus caused by cerebellar infarction is infrequent. When occlusive hydrocephalus is observed, ETV can be used successfully with minimal risks, especially with avoidance of a higher rate of infectious complications caused by external drainage systems.

Halo traction in basilar invagination: technical case report.

BACKGROUND: In the management of basilar invagination, traction therapy may help by pulling down the odontoid process away from the brain stem that may result in clinical and radiological improvement. We aimed to discuss the role of the halo vest apparatus traction on the reduction of severe anterior compression pathologies in basilar invagination. CASE DESCRIPTION: We describe a simple and safe cervical traction method by the halo vest apparatus that is followed by rigid posterior occipitocervical fixation and foramen magnum decompression in a patient who presented with basilar invagination and symptoms of severe brain stem compression. An MR-suitable halo vest apparatus was used for reduction of the deformity. The reduction of the basilar invagination was achieved gradually by distracting the halo crown in stages. CONCLUSION: The halo vest apparatus can be safely used in complex craniocervical junction anomalies. An effective cervical traction can be performed in basilar invagination, and reduction of the deformity may be achieved without the risk of overdistraction. In some cases, even partial reduction of the deformity may facilitate brain stem and spinal cord relief without any need of posterior decompression. Patients may benefit from ambulatory functions because bed rest is eliminated in this procedure. Neurovascular structures and the degree of the reduction can be observed on MRIs when an MR-suitable device is used.

Spontaneous relapsing and recurring large multiloculated posterior fossa enteric cyst.

Intracranial enterogenous cyst is an uncommon entity. We report a case of enterogenous cyst of the posterior fossa situated posterolateral to the brain stem and extending into the left CP angle cistern. Patient had spontaneous regression and recurrence of the cyst. Clinical features and radiological findings are described. Near total excision of the cyst was carried out through the retro mastoid route. Patient made a good postoperative recovery.

[A case of intracranial dural arteriovenous fistula presenting with brainstem infarction].

A 68-year-old female presented with the disturbance of brainstem function. Brain T2 weighted and FLAIR (fluid-attenuated inversion recovery) magnetic resonance imaging revealed the hyperintensity signal of the medulla oblongata, which led to diagnosis of brainstem infarction. Diagnostic cerebral angiography showed the dural arteriovenous fistula (DAVF) developed on the left transverse sinus (TS). Venous drainage route was consisted of retrograde leptomeningieal venous reflux of the cerebrum and spinal perimedullary vein via superior petrosal sinus. Venous hypertension of the brainstem was relieved by transvenous platinum coil selective embolization of superior petrosal sinus. The correct analysis of venous drainage pattern is essential for the curative endovascular surgery.

Brain stem ischemia from intracranial dural arteriovenous fistula: case report.

BACKGROUND: Intracranial dural arteriovenous fistulas (AVFs) with spinal perimedullary venous drainage are rarely reported, but most of the patients initially have presented with myelopathy or subarachnoid hemorrhage. This is the first report of the intracranial dural AVF patient who presented with brain stem infarction. CASE DESCRIPTION: A 38-year-old woman experienced nausea and vomiting with an acute onset, followed by vertigo. Magnetic resonance imaging showed ischemic lesion in the medulla oblongata, and she was then sent to our hospital. On admission, she had nystagmus, swallowing difficulties, Homer syndrome, and right hemiparesis and hemisensory disturbance. Cerebral angiography revealed dural AVF draining into spinal perimedullary veins at the left transverse-sigmoid sinus. The patient was treated by transvenous embolization under local anesthesia. A microcatheter proceeded to the left sigmoid sinus via the internal jugular vein, and embolization of the sinus was performed using coils without complications. The patient's swallowing difficulties improved over a few days after the embolization, and one month later, there remained only a slight mild hemiparesis and hemisensory disturbance. Six months after the onset, there was no ischemic lesion in the brain stem on magnetic resonance imaging. CONCLUSIONS: In this case, we showed the possibility of brain stem infarction, caused by the intracranial dural AVF.

Endovascular management of exsanguinating vertebral artery transection.

BACKGROUND: Vertebral artery (VA) transection is a rarely described entity that may present dramatically with a life-threatening external hemorrhage. CASE DESCRIPTION: A 25-year-old man that was victim of a terrorist attack presented a gunshot wound to the mouth with massive bleeding. The bullet perforated the oropharynx and injured the right VA. Combined antegrade and retrograde endovascular embolization by means of detachable coils allowed rapid control of the bleeding. CONCLUSION: Bleeding related to VA transection can be managed safely by means of endovascular combined approaches.

Transarterial coil embolization of a high-flow vertebrojugular fistula due to penetrating craniocervical trauma: case report.

BACKGROUND: Vertebrojugular fistulas after penetrating cervical trauma (gunshot or stab wounds) are rarely reported. Successful endovascular coil embolization of an acute fistulizing vertebral artery pseudoaneurysm involving an obstructed internal jugular vein is presented and the various treatment strategies for such a lesion are described. CASE DESCRIPTION: A 23-year-old man presented from an outside institution after sustaining 2 gunshot wounds in a civilian conflict. Neuroimaging revealed a right vertebral artery pseudoaneurysm, which formed a fistulous connection with the internal jugular vein. Because venous outflow obstruction was present just below the fistula, a high-flow shunt was directed intracranially. Both the pseudoaneurysm and arteriovenous fistula were accessed percutaneously via a transfemoral route and coil embolization was performed. Perfusion of the basilar artery circulation was assumed by the contralateral vertebral artery. The ipsilateral posteroinferior cerebellar artery filled through retrograde flow down the vertebral confluence. CONCLUSIONS: Coil embolization is a safe and reliable strategy by which to obliterate an acute traumatic vertebrojugular fistula as well as pseudoaneurysm. Serial angiographic follow-up is mandatory to document a persistent cure.