Yoshiaki Ikai

Germinoma in siblings: Case reports

We present the first reported cases of germinoma occurring in siblings of different genders. One tumor occurred in the left basal ganglia of a 7-year-old boy and the other in the suprasellar region of his 9-year-old sister. Both tumors were diagnosed as germinoma of two-cell pattern based on light and electron microscopic studies. Possible genetic factors responsible for this phenomenon are discussed.

Mechanical Thrombectomy for Acute Basilar Artery Occlusion in Early Therapeutic Time Window

Background: The natural history of basilar artery occlusion (BAO) is devastating, with morbidity rates increasing up to 80%. However, the efficacy of recanalization therapy for BAO has not been established as yet. Objective: We analyzed consecutive cases of BAO treated with mechanical thrombectomy (MT) to evaluate its safety and efficacy and to determine factors associated with the prognosis. Methods: Between October 2011 and September 2016, MT was performed in 34 patients with BAO. MT was performed using the Penumbra system and stent retriever. CT perfusion was used for evaluating patients. Cerebral blood flow (CBF) maps and cerebral blood volume (CBV) maps were evaluated. CBF/CBV mismatch was defined as ≥50% penumbra. Clinical outcomes were correlated with demographic, clinical, and radiographic findings. Results: The median baseline National Institutes of Health Stroke Scale score was 29 (14-33). The recanalization rate (≥thrombolysis in cerebral infarction grades 2b) was 100%. The median onset to recanalization time (OTR) was 197 (160-256) min. Favorable outcomes (modified Rankin Scale ≤2) at 90 days occurred in 56% (n = 19 of 34). The mortality rate at 90 days was 12% (n = 4 of 34). In univariate analysis, intravenous (IV) recombinant tissue-type plasminogen activator (rt-PA) use, and OTR were significantly associated with favorable outcomes. In a multivariate logistic regression model, IV rt-PA use and lower National Institute of Health Stroke Scale score were significantly related to favorable outcomes. Conclusion and Relevance: Multimodal endovascular therapy using the Penumbra system and stent retriever demonstrated a high recanalization rate and favorable outcomes for BAO. Both devices were feasible and effective in the treatment of BAO. An approach combining MT with IV thrombolysis provided a better recanalization rate and more favorable clinical outcomes.

Sensory aphasia after closed head injury.

A 51-year-old, right-handed male injured his head when drunk. After an initial mute state lasting for several hours, he exhibited fluent aphasia, impaired word finding, some verbal paraphasia and impaired verbal comprehension. A CT scan revealed a contusion in the left anterior temporal lobe. He was treated conservatively, and at the follow-up 6 months later, his sensory aphasia had recovered well. The relationship between closed head trauma and aphasia is reviewed with special attention to its nature and clinical course.

Mechanical Thrombectomy for Acute Anterior Cerebral Artery Occlusion

BACKGROUND We sought to examine the presentation, treatment, and outcomes of anterior cerebral artery (ACA) occlusions in patients undergoing mechanical thrombectomy (MT). METHODS Two-hundred ninety-eight consecutive patients with large-vessel occlusion treated with MT were analyzed to identify all patients with acute ACA occlusion who underwent MT. The primary end point was defined as achieving a thrombolysis in cerebral infarction score ≥2b. The secondary end point included the 90-day modified Rankin Scale (mRS) score and symptomatic intracranial hemorrhage. RESULTS Nine patients with a median National Institutes of Health Stroke Scale score of 24 presented with acute ACA occlusion. The median time from onset to recanalization was 229 minutes. The ACA occlusion was a primary embolic occlusion in 5 patients, secondary to an interventional maneuver in 4 patients. Recanalization (thrombolysis in cerebral infarction ≥2b) was achieved in 9 of 9 patients (100%) without procedural complications. All patients had a 90-day mRS score ≥3, and 2 patients had an mRS score of 6. Two patients developed hemorrhagic infarction, and 1 patient had subarachnoid hemorrhage. CONCLUSIONS Although MT can be considered in patients with ACA occlusions, our data suggest that future clinical trials are needed to determine the efficacy of MT for ACA occlusions. Unfavorable outcomes in our study were considered to occur because of a larger infarct volume due to internal carotid artery, middle cerebral artery, and anterior cerebral artery territory infarction. The time from onset to recanalization was longer because MT was performed for occlusions of multiple arteries.

Abstract WP12: Mechanical Thrombectomy for Basilar Artery Occlusion

Background and Purpose: Basilar artery occlusion (BAO) is an infrequent cause of stroke, accounting for 1.1% of acute ischemic stroke cases. The natural history of patients with BAO is devastating, with morbidity rates of up to 80%. No previous randomized controlled studies on the efficacy of recanalization therapy have been reported. Methods: In the present single-center study, consecutive BAO patients were treated with mechanical thrombectomy (MT) using the stent retriever and the Penumbra system. Computed tomography perfusion was used for patient evaluation. Clinical outcomes were correlated with demographic, clinical, and radiographic findings. Results: Between October 2011 and March 2017, MT was performed in 37 patients with BAO (mean age 70.1±10.9). Mean baseline National Institutes of Health Stroke Scale was 23±11. Recanalization rate (≧thrombolysis in cerebral infarction 2b) was 100%. Mean onset to recanalization time (OTR) was 226.3±117.8minutes. Favorable outcome at 90 days (modified Rankin scale≦2) was 60.6%. Mortality rate at 90 days was 10.8%. In an univariate analysis, IV rt-PA use, and OTR were significantly associated with favorable outcomes. In a multivariate logistic regression model, IV rt-PA use and lower NIHSS score were significantly related to favorable outcomes. Conclusions: Multimodal endovascular therapy using the Penumbra system and/or stent retriever demonstrated high recanalization rates and improved outcomes in BAO. Both devices were feasible and effective in the treatment of BAO. An approach combining MT with IV thrombolysis provided better recanalization rates and improved clinical outcomes.

A case of delayed distal coil migration after coil embolization of an unruptured distal azygos anterior cerebral artery aneurysm: A case report and literature review

Intraprocedural coil migration during endovascular treatment for an aneurysm that might carry serious ischemic complications is well known. On the other hand, delayed coil migration after endovascular treatment for an aneurysm is very rare. A 77-year-old woman was incidentally diagnosed with unruptured aneurysm associated with distal azygos anterior cerebral artery (ACA). The aneurysm was located at the distal bifurcation of the azygos ACA and was wide necked (approximately 7 mm in diameter). Endovascular coil embolization was selected and the aneurysm was occluded successfully, but 29 days after endovascular therapy, follow-up computed tomography (CT) and magnetic resonance (MR) angiography revealed distal coil migration in the peripheral portion of the ACA. In addition, CT on day 57 after therapy revealed the migrated coil had moved more distally. Fortunately, in the course of these events, the patient remained asymptomatic. To the best of our knowledge, this represents the first case of delayed distal coil migration associated with relatively rare azygos ACA aneurysm, and also the first report confirming more distal coil movement over time. In the future, a large number of patients could develop this complication as more aneurysms are aggressively treated with endovascular treatment. Knowledge regarding the possibility of delayed coil migration is thus important.

Optimal thresholds for ischemic penumbra predicted by computed tomography perfusion in patients with acute ischemic stroke treated with mechanical thrombectomy

Background and purpose Optimal thresholds for ischemic penumbra detected by CT perfusion (CTP) in patients with acute ischemic stroke (AIS) have not been elucidated. In this study we investigated optimal thresholds for salvageable ischemic penumbra and the risk of hemorrhagic transformation (HT). Methods A total of 156 consecutive patients with AIS treated with mechanical thrombectomy (MT) at our hospital were enrolled. Absolute (a) and relative (r) CTP parameters including cerebral blood flow (aCBF and rCBF), cerebral blood volume (aCBV and rCBV), and mean transit time (aMTT and rMTT) were evaluated for their value in detecting ischemic penumbra in each of seven arbitrary regions of interest defined by the major supplying blood vessel. Optimal thresholds were calculated by performing receiver operating characteristic curve analysis in 47 patients who achieved Thrombolysis In Cerebral Infarction (TICI) grade 3 recanalization. The risk of HT after MT was evaluated in 101 patients who achieved TICI grade 2b–3 recanalization. Results Absolute CTP parameters for distinguishing ischemic penumbra from ischemic core were as follows: aCBF, 27.8 mL/100 g/min (area under the curve 0.82); aCBV, 2.1 mL/100 g (0.75); and aMTT, 7.30 s (0.70). Relative CTP parameters were as follows: rCBF, 0.62 (0.81); rCBV, 0.83 (0.87); and rMTT, 1.61 (0.73). CBF was significantly lower in areas of HT than in areas of infarction (aCBF, p<0.01; rCBF, p<0.001). Conclusions CTP may be able to predict treatable ischemic penumbra and the risk of HT after MT in patients with AIS.

A case with coil embolization for ruptured aneurysm associated with fenestration of the posterior inferior cerebellar artery

An 87-year-old man hospitalized for subarachnoid hemorrhage showed a ruptured aneurysm arising from fenestration of the posterior inferior cerebellar artery. Endovascular treatment was selected and the aneurysm and superior limb were embolized completely using three coils. Fenestration of the posterior cerebellar artery is exceedingly rare. In addition, we present a first case of aneurysm as fenestration of the posterior inferior cerebellar artery that was definitively identified as a cause of bleeding.