Microvascular decompression of the posterior cerebral artery for treatment of oculomotor nerve palsy

Oculomotor nerve palsy resulting from non-aneurysmal vascular compression is extremely rare. Microvascular decompression (MVD) has been previously shown to improve oculomotor nerve palsy (ONP) secondary to arterial compression. A 71-year-old female, with a history of Cushing’s disease previously treated with two transsphenoidal resections and Gamma Knife radiosurgery, presented with one year of progressive left eye diplopia and was diagnosed with a partial left oculomotor nerve palsy. We performed an orbitozygomatic craniotomy for MVD of the left posterior cerebral artery, which was found to be compressing the oculomotor nerve against the tentorium. Unfortunately, the patient’s partial ONP remained unchanged at one year follow-up. The present case suggests inconsistent outcomes of MVD for ONP. Patients with prior sellar or parasellar irradiation may be less likely to benefit from this treatment approach.

Surgical Approaches for Symptomatic Cerebral Cavernous Malformations of the Thalamus and Brainstem

OBJECTIVE: Surgical resection of thalamic and brainstem cerebral cavernous malformations (CCMs) is associated with significant operative morbidity, but it may be outweighed, in some cases, by the neurological damage from recurrent hemorrhage in these eloquent areas. The goals of this retrospective cohort study are to describe the technical nuances of surgical approaches and determine the postoperative outcomes for CCMs of the thalamus and brainstem. MATERIALS AND METHODS: We reviewed an institutional database of patients harboring thalamic or brainstem CCMs, who underwent surgical resection from 2010 to 2014. The baseline and follow-up neuroimaging and clinical findings of each patient and the operative details of each case were evaluated. RESULTS: A total of eight patients, including two with thalamic and six with brainstem CCMs, were included in the study cohort. All patients had progressive neurological deterioration from recurrent CCM hemorrhage, and the median modified Rankin Scale (mRS) at presentation was 3. The median CCM maximum diameter and volume were 1.7 cm and 1.8 cm³, respectively. The thalamic CCMs were resected using the anterior transcallosal transchoroidal and supracerebellar infratentorial approaches each in one case (13%). The brainstem CCMs were resected using the retrosigmoid and suboccipital trans-cerebellomedullary fissure approaches each in three cases (38%). After a median follow-up of 11.5 months, all patients were neurologically stable or improved, with a median mRS of 2. The rate of functional independence (mRS 0-2) was 63%. CONCLUSION: Microneurosurgical techniques and approaches can be safely and effectively employed for the management of thalamic and brainstem CCMs in appropriately selected patients.

Eyebrow Incision for Surgical Evacuation of a Lobar Intracerebral Hematoma with a Novel Endoport System

Large lobar intracerebral hemorrhages (ICHs) can cause rapid neurological deterioration, and affected patients have low rates of survival and functional independence. Currently, the role of surgical intervention in the management patients with lobar ICHs is controversial. Minimally invasive technologies have been developed which may potentially decrease the operative morbidity of ICH surgery. The aim of this case report is to describe the technical aspects of the use of a novel minimally invasive endoport system, the BrainPath (NICO, Indianapolis, IN, USA), through an eyebrow incision for evacuation of a large lobar hematoma. An 84-year-old female presented with a left frontal ICH, measuring 7.5 cm in maximal diameter and 81 cm³ in volume, secondary to cerebral amyloid angiopathy. Through a left eyebrow incision, a miniature modified orbitozygomatic craniotomy was performed, which allowed endoport cannulation of the hematoma from a lateral subfrontal cortical entry point. Endoport-assisted hematoma evacuation resulted in nearly 90% volume reduction and improvement of the patient's functional status at clinical follow-up. We found that minimally invasive endoport technology can be employed in conjunction with conventional neurosurgical skull base principles to achieve safe and effective evacuation of large lobar hematomas in carefully selected patients.

Preoperative Embolization of Cerebral Arteriovenous Malformations with Silk Suture and Particles: Technical Considerations and Outcomes

OBJECTIVE: Embolization of cerebral arteriovenous malformations (AVMs) is commonly performed prior to surgical resection in order to reduce intraoperative bleeding and improve the safety of resection. Although most modern embolization procedures utilize permanent embolic agents, silk suture and polyvinyl alcohol (PVA) particles may offer unique advantages for preoperative devascularization. The aims of this retrospective cohort study are to describe the technical considerations and determine the outcomes for preoperative silk suture and PVA particle embolization (SPE) of AVMs. MATERIALS AND METHODS: We performed a retrospective review of our AVM embolization database. AVM patients who underwent preoperative SPE and subsequent surgical resection were included for analysis. Baseline patient demographics, AVM characteristics, embolization and operative records, and post-treatment outcomes were reviewed. RESULTS: A total of 11 patients who underwent 12 preoperative SPE procedures were included for analysis. Five AVMs were ruptured (45%), and the median nidus volume was 3.0 cm3 (range: 1.3-42.9 cm³). The Spetzler-Martin grade was I-II in seven patients (64%) and III-IV in four patients (36%). The degree of nidal obliteration was less than 25% in two procedures (17%), 25-50% in one procedure (8%), 50-75% in eight procedures (67%), and greater than 75% in one procedure (8%). The rates of post-embolization AVM hemorrhage and mortality were 8% and 0%, respectively. The postoperative angiographic obliteration rate was 100%, and the modified Rankin Scale score improved or stable in 91% of patients (median follow-up duration 2 months). CONCLUSION: Preoperative AVM SPE affords a reasonable risk to benefit profile for appropriately selected patients.

Preoperative Embolization of Cerebral Arteriovenous Malformations with Silk Suture and Particles: Technical Considerations and Outcomes

OBJECTIVE: Embolization of cerebral arteriovenous malformations (AVMs) is commonly performed prior to surgical resection in order to reduce intraoperative bleeding and improve the safety of resection. Although most modern embolization procedures utilize permanent embolic agents, silk suture and polyvinyl alcohol (PVA) particles may offer unique advantages for preoperative devascularization. The aims of this retrospective cohort study are to describe the technical considerations and determine the outcomes for preoperative silk suture and PVA particle embolization (SPE) of AVMs. MATERIALS AND METHODS: We performed a retrospective review of our AVM embolization database. AVM patients who underwent preoperative SPE and subsequent surgical resection were included for analysis. Baseline patient demographics, AVM characteristics, embolization and operative records, and post-treatment outcomes were reviewed. RESULTS: A total of 11 patients who underwent 12 preoperative SPE procedures were included for analysis. Five AVMs were ruptured (45%), and the median nidus volume was 3.0 cm3 (range: 1.3-42.9 cm³). The Spetzler-Martin grade was I-II in seven patients (64%) and III-IV in four patients (36%). The degree of nidal obliteration was less than 25% in two procedures (17%), 25-50% in one procedure (8%), 50-75% in eight procedures (67%), and greater than 75% in one procedure (8%). The rates of post-embolization AVM hemorrhage and mortality were 8% and 0%, respectively. The postoperative angiographic obliteration rate was 100%, and the modified Rankin Scale score improved or stable in 91% of patients (median follow-up duration 2 months). CONCLUSION: Preoperative AVM SPE affords a reasonable risk to benefit profile for appropriately selected patients.

Endovascular Mechanical Thrombectomy for Acute Ischemic Stroke: A New Standard of Care / 대한뇌졸중학회지

The treatment of acute ischemic stroke (AIS) in the setting of intracranial large artery occlusion (LAO) with intravenous tissue plasminogen activator (IV-tPA) is associated with low rates of recanalization and high rates of neurological morbidity and functional dependence. Endovascular intervention, particularly mechanical thrombectomy, is a promising therapeutic adjunct to IV-tPA for the treatment of acute LAO. However, until recently, its efficacy has been controversial. In this brief review, we analyze the criticisms of three negative randomized controlled trials (RCT) of endovascular stroke treatment and evaluate the results from seven positive endovascular stroke RCTs that have recently been presented or published. IMS III, MR RESCUE, and SYTHESIS Expansion were three RCTs that failed to show a benefit from endovascular stroke therapy. Major criticisms of these studies included a lack of routine screening for LAO, resulting in the selection of AIS patients without LAO for endovascular intervention, and a low utilization rate of modern endovascular thrombectomy devices, leading to substandard rates of successful recanalization. MR CLEAN was the first phase III RCT to show a significant clinical benefit from endovascular stroke therapy. The dissemination of its findings elicited a cascade of positive results from, to date, six additional endovascular stroke RCTs, ESCAPE, EXTEND-IA, SWIFT PRIME, REVASCAT, THERAPY, and THRACE, which were halted prematurely for efficacy. The cumulative evidence from these studies shows an overwhelming benefit from the endovascular treatment of acute LAO, therefore effectively establishing a new standard of care for the management of AIS.

Endovascular Management of Intracranial Aneurysms: Advances in Stenting Techniques and Technology

No abstract available.

Balloon Anchor Technique for Pipeline Embolization Device Deployment Across the Neck of a Giant Intracranial Aneurysm

Treatment of giant intracranial aneurysms, via either surgical or endovascular approaches, is associated with a high level of technical difficulty as well as a high rate of treatment-related morbidity and mortality. Flow-diverting stents, such as the Pipeline embolization device (PED), have drastically altered the therapeutic strategies for the treatment of giant aneurysms. Gaining endovascular access using a microcatheter to the portion of the parent artery distal to the aneurysm neck is requisite for safe and effective stent deployment. Giant aneurysms are often associated with vascular tortuosity, which necessitates significant catheter support systems to enable maneuvering of PEDs across the aneurysm neck. This is also required in order to reduce the probability of stent herniation within giant aneurysms. We report on a case of a giant supraclinoid internal carotid artery (ICA) aneurysm which was treated successfully with a PED utilizing a balloon anchor technique to facilitate direct microcatheter access across the aneurysm neck.

Microsurgical Strategies Following Failed Endovascular Treatment with the Pipeline Embolization Device: Case of a Giant Posterior Cerebral Artery Aneurysm

Treatment of giant posterior circulation aneurysms, via endovascular or microsurgical approaches, carries a high risk of morbidity and mortality. While flow-diverting stents (FDSs) represent a potent therapy for endovascular reconstruction of complex aneurysms, they are also associated with novel complications for which effective salvage techniques are lacking. We present a unique complication from failed treatment with a FDS. A 51 year-old male presented with increasing headaches secondary to a giant, fusiform aneurysm of the left posterior cerebral artery, which was largely thrombosed. Due to progressive enlargement of the aneurysm corresponding to worsening clinical symptoms, the lesion was treated with two Pipeline embolization devices (ev3, Plymouth, MN, United States). Three months after Pipeline embolization device treatment, complete posterior cerebral artery occlusion was observed at the origin of the proximal stent. Despite the lack of arterial inflow, the aneurysm dome continued to grow, resulting in obstructive hydrocephalus. Therefore microsurgical intervention was undertaken to trap and excise the aneurysm. The patient's postoperative course was complicated by multiple venous infarcts, ultimately resulting in death. Successful microsurgical obliteration of aneurysms previously treated with FDSs is extremely difficult. A combination of judicious preoperative planning and meticulous intraoperative surgical technique are requisite for effective management of these complicated cases.

Intravenous Versus Intra-arterial Thrombolysis for Acute Ischemic Stroke Secondary to Basilar Artery Occlusion

No abstract available.

Predictive Capability of the Spetzler-Martin versus Supplementary Grading Scale for Microsurgical Outcomes of Cerebellar Arteriovenous Malformations

The recently described supplementary grading scale may be superior to the widely used Spetzler-Martin grading scale in the prediction of microsurgical outcomes for cerebellar arteriovenous malformations (AVM). We report two cases of ruptured cerebellar AVMs with the same Spetzler-Martin grade but different supplementary grades treated with microsurgical resection. Both patients had symptomatic brainstem compression from cerebellar hematomas and subsequently underwent uncomplicated surgeries; however, their outcomes were significantly different. It has previously been proposed that AVMs distort cerebellar anatomy in a different manner than supratentorial cerebral anatomy thereby potentially resulting in misrepresentation when utilizing the Spetzler-Martin grading scale. However, the components of the supplementary grading scale are independent of cerebellar anatomy, which may explain why it has been shown to be better than the Spetzler-Martin grading scale for prediction of surgical outcomes. In addition, due to the smaller volume of the posterior fossa compared to the supratentorial compartment, rupture of cerebellar AVMs may result in rapid and catastrophic neurological compromise. Therefore, the role of microsurgery may be more critical for AVMs of the cerebellar than for those located elsewhere. Simple and effective grading systems are invaluable tools for clinical and surgical decision-making, although the decisions rendered should always be made in conjunction with the patient's presentation and the physician's experience.

Microsurgical Extraction of a Malfunctioned Pipeline Embolization Device Following Complete Deployment

The Pipeline Embolization Device (PED) is an effective treatment approach for complex intracranial aneurysms. Intraprocedural complications during PED deployment are seldom reported. We report a rare complication of a PED malfunction identified immediately following complete deployment during endovascular treatment of a giant middle cerebral artery (MCA) bifurcation aneurysm. After multiple failed attempts at endovascular retrieval of the malfunctioned PED, the patient was taken for microsurgical extraction due to accumulation of thrombus on the proximal unopened portion of the stent and widespread distal dissemination of emboli. After removing the PED from the vessel lumen and resecting the giant aneurysm, we could not reanastamose the proximal MCA to the distal segment. The management of PED malfunction is poorly understood. While removal of an incompletely deployed PED may be undertaken with limited adverse effects, retrieval of a fully deployed PED is associated with a much higher risk of morbidity. Until larger case series of such complications better define the risks and benefits of endovascular or microsurgical retrieval of malfunctioned PEDs, the management of these rare intraprocedural complications will be based on the unique aspects of each individual case and the expertise of the treating neurointerventionalist.