Hidenori Miyake

Direct Revascularization to the Anterior Cerebral Artery Territory in Patients with Moyamoya Disease: Report of Five Cases

OBJECTIVE In some patients with moyamoya disease, the development of spontaneous leptomeningeal collateral channels between the anterior cerebral artery (ACA) and other major arteries is poor. These patients require revascularization not only to the territory of the middle cerebral artery (MCA) but also to that of the ACA. For reliable revascularization to the ACA territory, we performed superficial temporal artery (STA)-ACA direct anastomosis in 5 of 58 patients with moyamoya disease who underwent cerebral revascularization at our institute during the last 8 years. METHODS Because two patients presented with ischemic symptoms corresponding to the ACA territory after the ipsilateral STA-MCA anastomosis, we subsequently performed STA-ACA anastomosis. In three patients in whom hypoperfusion in the ACA territory was suspected based on preoperative angiograms and/or stimulated cerebral blood flow studies, we performed STA-ACA and STA-MCA anastomoses during a single operative procedure. After paramedian frontal craniotomy (diameter, approximately 5 cm), STA-ACA anastomosis was performed at the convexity, using a cortical branch of the ACA as a recipient. An interposed STA graft was used in four patients; all of the grafts were shorter than 4 cm. RESULTS Bypass flow was satisfactory in four patients. One patient who underwent simultaneous STA-ACA and STA-MCA anastomoses had poor bypass flow, probably caused by spontaneous leptomeningeal collateral channels between the ACA and MCA. No patient had an ischemic attack after surgery. CONCLUSION Our method using a cortical branch of the ACA as a recipient and a branch of the STA for the interposed graft can be performed at the convexity and much more easily than in a deep operative field. Our experience with STA-ACA anastomosis indicates that this procedure is effective for revascularization of the ACA territory in patients with moyamoya disease.

Dural arteriovenous malformation in the anterior cranial fossa: Report of a case

We present an unusual case involving intracranial arteriovenous malformations in the anterior cranial fossa located symmetrically on both sides. A mixed pial and dural arteriovenous malformation, the nidus of which was localized in the brain parenchyma, was found on the right side and a pure dural arteriovenous malformation on the left side. Our case is felt to support the hypothesis of a congenital origin for dural arteriovenous malformation in the anterior cranial fossa, because the dural arteriovenous malformation coexisted with the mixed pial and dural arteriovenous malformation, which can be attributed to a disturbance of normal embryonic development.

Clinical Predictors of Transient Ischemic Attack, Stroke, or Death within 30 Days of Carotid Artery Stent Placement with Distal Balloon Protection

PURPOSE Carotid artery stent placement has been accepted as an effective alternative to carotid endarterectomy (CEA), especially in patients at high risk in the setting of CEA. The purpose of this study was to determine potential clinical risk factors for the development of postprocedural neurologic deficits after carotid artery stent placement. MATERIALS AND METHODS The clinical characteristics of 58 patients (49 men, nine women; 41 at high risk with CEA, 17 at low risk; median age, 70 years) who underwent carotid artery stent placement with distal balloon protection for 65 hemispheres/arteries (31 asymptomatic lesions and 34 symptomatic lesions) and the combined 30-day complication rates (transient ischemic attack [TIA], minor stroke, major stroke, or death) were analyzed. RESULTS Six patients (9.0%) experienced a TIA and one patient (1.5%) had a major stroke (1.5%) within 30 days of the procedure. There were no deaths, so the overall 30-day combined stroke and death rate was 1.5%. The chi(2) test revealed that advanced age (>75 years) was a significant clinical predictor of 30-day combined neurologic complications and major adverse effects (P < .01). In addition, a symptomatic lesion was marginally associated with the 30-day incidence of neurologic ischemia on the ipsilateral side (P = .049). CONCLUSIONS Our data suggest that carotid artery stent placement with distal balloon protection can be performed with similar periprocedural complication rates as CEA. CEA should be the first-line treatment in the management of patients older than 75 years of age.

Intraoperative monitoring during carotid cross-clamping with near-infrared spectroscopy: a preliminary study.

Near infrared spectroscopy (NIRS) is a noninvasive and real-time method for monitoring oxy-[HbO2] and deoxyhemoglobin [Hb] in tissue, and is suitable for intraoperative monitoring. In this study, NIRS monitoring was performed on 10 patients during carotid cross-clamping. The data were analyzed with a theoretical cerebral hemoglobin model developed to identify an ischemic pattern using NIRS parameters. Temporal profiles of changes in [HbO2] and [Hb] were divided into three phases: initial (immediately after clamping), second (during clamping), and last phase (immediately after clamp release). In the initial phase, [HbO2] decreased and [Hb] increased in all the cases. In the second phase, recovery patterns of [HbO2] were classified into three groups: complete (3 patients), incomplete (3 patients), and no recovery (2 patients). In the last phase, the [HbO2] increased and [Hb] decreased. Relative changes in [HbO2] and [Hb] measured by NIRS were correlated with changes in blood flow of the internal carotid artery (ICA) measured by a magnetic flowmeter and stump pressure of the internal carotid arteries. The degree of [HbO2] decrease in the initial phase was significantly correlated with ICA blood flow before clamping (r=0.90, p<0.05). Three of the 4 patients with ICA stump pressure over 50 mmHg showed a complete recovery pattern in the second phase, while all 4 patients with ICA stump pressure under 50 mmHg showed an incomplete recovery or no recovery pattern with NIRS. These results suggest that NIRS is useful in evaluating changes in cerebral blood flow and the extent of hemodynamic reserve during carotid cross-clamping.

Clinical predictors of delayed cerebral ischemia after subarachnoid hemorrhage: first experience with coil embolization in the management of ruptured cerebral aneurysms.

Objective The purpose of this study was to clarify the clinical predictors of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Methods 102 patients with ruptured cerebral aneurysms were treated (77 by clipping and 25 by coiling). 40 patients were male and 62 were female. Median age was 59 years (range 31–88). The modified Rankin Scale was used to assess functional outcomes 3 months after treatment or at discharge. The associations between potential clinical risk factors and DCI after SAH were assessed using the χ2 test. Results 52 patients (51.0%) had a good outcome and 13 patients (12.7%) died despite treatment. DCI was observed in 26 patients and hydrocephalus was observed in 37 patients. There were marginal differences in clinical outcomes between the treatment groups (p=0.053), mainly because functional outcomes were significantly superior in the coiling group (p=0.04) in patients with severe SAH. DCI was seen less frequently in the coiling group than in the clipping group (4.0% vs 32.4%, p=0.001). The presence of hydrocephalus was significantly associated with the occurrence of DCI (p<0.001). Multivariate logistic regression analysis also showed that the treatment modality and the presence of hydrocephalus were independent risk factors for DCI. Conclusion DCI was less frequently observed in the coiling group, and clinical outcomes were also superior in the coiling group, especially for patients with severe SAH. The results showed a significant correlation between DCI and hydrocephalus.

Repeated short-term recurrence of a chronic subdural hematoma associated with metastasis to hematoma capsule originating from extracranial malignant tumor

BACKGROUND The recurrence rate of chronic subdural hematoma (CSDH) after trepanation is relatively high and involves various factors. We encountered an extremely rare case in which metastasis of an extracranial malignant tumor to the hematoma capsule was thought to be causing short-term repeated recurrences of CSDH. CASE DESCRIPTION The patient was a 74-year-old man who had undergone bur hole evacuation of left CSDH 7 months earlier and had been receiving chemotherapy for stage IV gastric cancer for the preceding 6 months. He presented with symptoms of right hemiparesis and was diagnosed with left CSDH. Bur hole evacuation was performed twice, but the hematoma enlarged again both times within a short period. A third bur hole evacuation was performed after middle meningeal artery embolization, but the hematoma again enlarged shortly thereafter. Hematoma enlargement was finally suppressed by extracting the hematoma capsule under craniotomy. In histopathologic examinations, hematoxylin-eosin staining showed poorly differentiated adenocarcinoma primarily along the luminal side of the hematoma capsule and immunohistochemical staining showed results identical to findings from the existing gastric cancer. Pathologic results confirmed metastasis of the gastric cancer to the hematoma capsule, and this was considered to be the cause of short-term repeated recurrence of CSDH. CONCLUSIONS To the best of our knowledge, this is the first report of metastasis to a hematoma capsule originating from an extracranial malignant tumor. The clinical course in the present case suggests metastasis of extracranial malignant tumor to the CSDH capsule as an extremely rare cause of recurrence.