Naoki Akioka

Changes in cognitive function during the 1-year period following endarterectomy and stenting of patients with high-grade carotid artery stenosis

BackgroundIn patients with severe carotid artery stenosis, cognitive decline and changes in cognitive function before to after treatment have been noted, though the true effects of treatment in such patients remain unclear. A convenient and repeatable neuropsychological test battery is needed for such patients.MethodsIn 26 patients with severe carotid artery stenosis treated by carotid endarterectomy (CEA) and stenting (CAS), cognitive function was examined before and 1 week, 3 months, 6 months, and 1 year after treatment. RBANS and MMSE were selected as a test battery, and changes in test scores and long-term results of revascularization were evaluated.ResultsRBANS was useful and suitable for neuropsychological testing in such patients, and yielded the following results: (1) Patients before treatment had, on average, RBANS scores rated low average, with mild but relatively diffuse cognitive impairment; (2) RBANS scores were increased significantly at 3 months after CEA and CAS, and cognitive improvement was maintained over 1 year; and (3) scores were decreased temporarily at 1 week after CEA, but not after CAS.ConclusionsPatients with severe carotid artery stenosis exhibited mild decline in cognitive function, which was improved after CEA and CAS. RBANS is a suitable test battery for this type of patient.

Specific Shrinkage of Carotid Forks in Moyamoya Disease: A Novel Key Finding for Diagnosis

This study was aimed to analyze the outer diameter of the involved arteries in moyamoya disease, using three-dimensional (3D) constructive interference in steady state (CISS) and direct surgical inspection. Radiological evaluation was performed in 64 patients with moyamoya disease. As the controls, six patients with severe middle cerebral artery (MCA) stenosis and 17 healthy subjects were also recruited. On 3D-CISS, the outer diameter was quantified in the supraclinoid portion of internal carotid artery (C1), the horizontal portions of MCA (M1) and anterior cerebral artery (A1), and basilar artery. The involved carotid fork was directly observed during surgery in another series of three adult patients with moyamoya disease. In 53 adult patients with moyamoya disease, the outer diameters of C1, M1, and A1 segments were 2.3 ± 0.7 mm, 1.3 ± 0.5 mm, and 1.0 ± 0.4 mm in the involved side (n = 91), being significantly smaller than the control (n = 17), severe M1 stenosis (n = 6), and non-involved side in moyamoya disease (n = 15, P < 0.01). There were significant correlations between Suzuki’s angiographical stage and the outer diameters of C1, M1, and A1 (P < 0.001). The laterality ratio of C1 and M1 was significantly smaller in unilateral moyamoya disease (n = 20) than the controls and severe MCA stenosis (P < 0.01). Direct observations revealed a marked decrease in the outer diameter of the carotid fork (n = 3). These findings strongly suggest specific shrinkage of the involved arteries in moyamoya disease, which may provide essential information to distinguish moyamoya disease from other intracranial arterial stenosis and shed light on the etiology and novel diagnosis cue of moyamoya disease.

Reversal of Cognitive Dysfunction by Total Removal of a Large Lateral Ventricle Meningioma: A Case Report with Neuropsychological Assessments

Although cognitive impairment is one of the major symptoms of ventricular tumors, few studies have reported the details of cognitive impairment before and after their surgical removal. The expected effects on cognitive function should also be considered when choosing a surgical approach. We report the case of a large lateral ventricle meningioma in which cognitive impairment was detected on detailed neuropsychological examinations. The tumor was totally removed through the right superior temporal gyrus. Postoperative neuropsychological assessment revealed the reversal of cognitive impairment. As cognitive impairment is complex and easily overlooked, it is important to precisely assess neuropsychological function in patients with large brain tumors.

Clear cell meningioma with histologically aggressive appearance and clinically aggressive behavior: A case report

Clear cell meningioma (CCM) is an uncommon variant of meningioma, corresponding to WHO grade II. We present a case of CCM with histologically aggressive appearance and clinically aggressive behavior. The tumor demonstrated rapid regrowth and brain metastasis. The histological progression from the ordinal CCM to the atypical area and higher MIB‐1 index was observed. We assume that the short time of recurrence and metastasis may result from atypical histological features in our case. If the CCM has a histologically aggressive appearance as in our case, we suggest that postoperative adjuvant radiotherapy should be performed despite total resection of the tumor.

Berlin Grading System Can Stratify the Onset and Predict Perioperative Complications in Adult Moyamoya Disease.

BACKGROUND The grading system for moyamoya disease is not established. OBJECTIVE To assess the usefulness of a recently proposed grading system for stratifying the clinical severity and predicting postoperative morbidity in adult moyamoya disease. METHODS We investigated 176 hemispheres from 89 adult patients who were diagnosed with moyamoya disease in Japan. Their data were analyzed using the Berlin grading system with minor modifications. After summarizing the numerical values for digital subtraction angiography (1-3 points), magnetic resonance imaging (0-1 points), and single-photon emission computed tomography (0-2 points), 3 grades of moyamoya disease were defined: mild (grade I) = 1 to 2 points, moderate (grade II) = 3 to 4 points, and severe (grade III) = 5 to 6 points. In total, 82 of 161 hemispheres underwent superficial temporal artery to middle cerebral artery anastomosis and indirect synangiosis. Postoperative neurological morbidity was included within 30 d after surgery. RESULTS Preoperative examinations categorized 87 hemispheres as grade I, 39 as grade II, and 50 as grade III. There was a significant correlation between the Berlin grading system and clinical severity (P < .001). Perioperative complications occurred in 12 of 82 (14.6%) hemispheres, including transient ischemic attack in 3 hemispheres, ischemic stroke in 4 hemispheres, symptomatic hyperperfusion in 4 hemispheres, and intracerebral hemorrhage in 1 hemisphere. The Berlin grading system was related to their occurrence (P < .001). CONCLUSION The Berlin grading system facilitates the stratification of clinical severity and predicting postoperative neurological morbidity in adult moyamoya disease, thereby suggesting its general usage in clinical practice.

Pathophysiology of acute cerebrovascular syndrome in patients with carotid artery stenosis: a magnetic resonance imaging/single-photon emission computed tomography study.

BACKGROUND The mechanisms underlying acute cerebrovascular syndrome in patients with carotid artery stenosis remain unclear. OBJECTIVE To assess the relationships among infarct localization, hemodynamics, and plaque components. METHODS This prospective study included 38 patients with acute cerebrovascular syndrome resulting from ipsilateral carotid artery stenosis. Cerebral infarct localization was categorized into 3 patterns (cortical, border zone, and mixed pattern). Carotid plaque components were evaluated with T1-weighted magnetic resonance imaging and time-of-flight imaging. Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were also quantified. RESULTS Infarcts were identified in 38 patients with the use of diffusion-weighted magnetic resonance imaging. On the basis of the assessment of hemodynamics, the cortical pattern was seen in 18 of 21 patients with type 1 ischemia (normal CBF, normal CVR), whereas the mixed pattern was seen in 2 patients with type 2 ischemia (normal CBF, impaired CVR) and 12 of 15 patients with type 3 ischemia (impaired CBF, impaired CVR). The plaque components were categorized into fibrous (4 patients), lipid-rich (14 patients), and intraplaque hemorrhage (IPH; 20 patients). Of the patients with fibrous plaque, 2 had border-zone and 2 had mixed-pattern infarcts. Of the patients with lipid-rich plaque, 7 had cortical and 6 had mixed-pattern infarcts. Of patients with intraplaque hemorrhage, 11 had cortical and 9 had mixed-pattern infarcts. CONCLUSION Cortical infarction occurs as a result of vulnerable plaque. Reduced cerebral perfusion induces border-zone infarction. Both factors are implicated in mixed-pattern infarction. Developments in noninvasive diagnostic modalities allow us to explore the mechanisms behind acute cerebrovascular syndrome in carotid artery stenosis and to determine the ideal therapies.

Headache attack followed by rapid disease progression in pediatric moyamoya disease—how should we manage it?

Case reportA 4-year-old female was presented at our hospital with frequent right frontal headache attack. She was diagnosed with moyamoya disease and was conservatively followed up. One year later, the frequency of headache gradually decreased. However, follow-up MR imaging revealed that the disease stage markedly progressed in the right side and cerebral infarction occurred in the temporal lobe with atrophy of the right frontal lobe. She underwent direct and indirect revascularization on the right side.ConclusionAware of this case, we would like to emphasize that headache may be one subtype of ischemic attacks and require frequent MR follow-up to see the disease course. If there is any sign of disease progression, immediate surgical intervention should be indicated to avoid irreversible brain damage.

Superficial temporal artery to middle cerebral artery anastomosis for neovascular glaucoma due to common carotid artery occlusion.

Background: Common carotid artery (CCA) occlusion sometimes requires surgical revascularization to resolve persistent cerebral/ocular ischemia. High-flow bypass is often indicated in these cases, using the interposed graft such as saphenous vein and radial artery. However, high-flow bypass surgery is invasive and may provide excessive blood flow to ischemic brain. In this report, we present a case that developed neovascular glaucoma due to CCA occlusion and was successfully treated with superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. Case Description: A 61-year-old male complained of left visual disturbance and was admitted to our hospital. He underwent carotid endarterectomy for left internal carotid artery stenosis in previous hospital 1-year before, but he experienced left visual disturbance after surgery. Postoperative examinations revealed that the CCA was occluded. His visual disturbance gradually progressed, and he was diagnosed as neovascular glaucoma. None of ophthalmological therapy could improve his symptoms. Blood flow measurement showed an impaired reactivity to acetazolamide in the left cerebral hemisphere. Cerebral angiography demonstrated that the left STA was opacified through the muscular branches from the left deep cervical artery. Therefore, he successfully underwent left STA-MCA double anastomosis. His visual acuity improved and new blood vessels around the iris markedly decreased 3 months after surgery. Conclusions: Precise radiological examination may enable standard STA-MCA anastomosis even in patients with CCA occlusion.

Chronic Subdural Hematoma Infected by Propionibacterium Acnes: A Case Report

We present a very rare case of a patient with an infected subdural hematoma due to Propionibacterium acnes. A 63-year-old male complained of dizziness and was admitted to our hospital. He had a history of left chronic subdural hematoma due to a traffic accident, which had been conservatively treated. Physical, neurological and laboratory examinations revealed no definite abnormality. Plain CT scan demonstrated a hypodense crescentic fluid collection over the surface of the left cerebral hemisphere. The patient was diagnosed with chronic subdural hematoma and underwent burr hole surgery three times and selective embolization of the middle meningeal artery, but the lesion easily recurred. Repeated culture examinations of white sedimentation detected P. acnes. Therefore, he underwent craniotomy surgery followed by intravenous administration of antibiotics. The infected subdural hematoma was covered with a thick, yellowish outer membrane, and the large volume of pus and hematoma was removed. However, the lesion recurred again and a low-density area developed in the left frontal lobe. Craniotomy surgery was performed a second time, and two Penrose drainages were put in both the epidural and subdural spaces. Subsequently, the lesions completely resolved and he was discharged without any neurological deficits. Infected subdural hematoma may be refractory to burr hole surgery or craniotomy alone, in which case aggressive treatment with craniotomy and continuous drainage should be indicated before the brain parenchyma suffers irreversible damage.

Sporadic hemangioblastoma of the film terminale with peritumoral cyst

Background: Spinal hemangioblastoma originating from the film terminale are rare tumors. Here, we present a film terminale hemangioblastoma and review the appropriate literature. Case Description: A 37-year-old female presented with bilateral lower extremity pain without a focal neurological deficit. The magnetic resonance (MR) image demonstrated an intradural spinal tumor at the L1 level, which was accompanied by peritumoral cysts. In addition, there were multiple surpentine flow voids (e.g., consistent with torturous and convoluted vessels), which is typical for hemangioblastoma. At surgery, a spinal hemangioblastoma originating from the film terminale with peritumoral cysts at the L1 level was fully excised without producing a focal postoperative neurological deficit. Histological examination revealed stromal cells with vacuolated cytoplasm and small nuclei in a rich capillary network accompanied by several enlarged vessels. These finding were compatible with a hemangioblastoma. Conclusions: We reported a rare case of a hemangioblastoma originating from the conus presenting at the L1 level. Complete surgical resection was accomplished without any motor deficit.