Masaaki Shibukawa

Primary intracerebral hemorrhage in Izumo City, Japan: incidence rates and outcome in relation to the site of hemorrhage.

OBJECTIVEThe aim of this community-based study was to investigate the incidence rates and outcome of primary intracerebral hemorrhage (ICH) in relation to the site of hemorrhage. METHODSThe subjects were 350 patients with primary first-ever ICH who were treated during the 8-year period 1991 to 1998 in Izumo City, Japan. RESULTSThe crude and age- and sex-adjusted incidence rates for all types of ICH were 52 and 47 per 100,000 population, respectively, for all ages. The most common site of ICH was the putamen (120 patients, 34%), followed by the thalamus (115, 33%), lobar areas (53, 15%), brainstem (30, 9%), cerebellum (25, 7%), and caudate nucleus (7, 2%). The crude and age- and sex-adjusted annual incidence rates per 100,000 population were 18 and 16 for putaminal, 17 and 15 for thalamic, 8 and 7 for lobar, 4 and 3 for cerebellar, 4 and 4 for brainstem, and 1 and 1 for caudate hemorrhages, respectively. The Glasgow Coma Scale scores on admission were best in patients with cerebellar hemorrhage and worst in those with brainstem hemorrhage. Surgery was performed for 34% of putaminal, 9% of thalamic, 14% of caudate, 21% of lobar, and 32% of cerebellar hemorrhages but not for brainstem hemorrhages. The 30-day case fatality rate was 11% for putaminal, 9% for thalamic, 14% for caudate, 11% for lobar, 0% for cerebellar, and 53% for brainstem hemorrhages. When patients with ICH were analyzed as a whole, the overall survival rates at 30 days, 3 months, and 3 years were 87, 83, and 73%, respectively. Both the short-term and long-term outcomes after ICH were directly related to the site of hemorrhage and the severity of bleeding, which was assessed by the hematoma volume and Glasgow Coma Scale score. Overall, 190 (54%) of 350 patients had a favorable outcome, and 55 (16%) had died at discharge. CONCLUSIONMarked differences were observed in the incidence rates and outcome of primary ICH in relation to the site of hemorrhage. The differences in outcome were primarily a result of differences in the severity of bleeding for each ICH subtype.

Expression of vascular endothelial growth factor in dura mater of patients with moyamoya disease

Vascular endothelial growth factor (VEGF) has been found to be involved in vasculogenesis in different intracranial lesions. We investigated meningeal cellularity and VEGF expression in dura mater of patients with and without moyamoya disease. Nine dural specimens from nine cerebral hemispheres of seven patients with moyamoya disease and four control dural specimens from four non-moyamoya patients were collected during surgery and investigated. Dural specimens were immunohistochemically stained with VEGF antibody, and then meningeal cellularity and VEGF expression in dural tissue were analyzed. The mean ± standard error (SE) of total number of meningeal cells (meningeal cellularity) in dural tissue was 21.5 ± 3.0 in the moyamoya disease patients, whereas it was 2.7 ± 0.7 in control patients. The mean ± SE of VEGF expression was 51.1 ± 4.9% in the moyamoya disease patients, whereas it was 13.8 ± 5.9% in control patients. The meningeal cellularity and VEGF expression were statistically significantly higher in the moyamoya group in comparison to control group (p < 0.0001). Meningeal cellularity and VEGF expression are significantly increased in dura mater of the patients with moyamoya disease.

CT perfusion imaging for childhood moyamoya disease before and after surgical revascularization

SummaryMoyamoya disease is a progressive occlusive disease of the circle of Willis with prominent collateral arterial formation. We report on a 12-year-old girl with moyamoya disease presenting with transient ischemic attacks (TIAs). Surgical indirect revascularization was performed. The patient did not suffer further TIAs at 12 month follow-up. Pre and postoperative cerebral perfusion were studied in quantitative single photon emission computerized tomography (SPECT) and CT perfusion imaging. CT perfusion imaging demonstrated postoperatively increased cerebral blood flow as well as SPECT before and after revascularization. Furthermore, the area of decreased vascular reserve in SPECT with acetazolamide corresponded to areas of increased cerebral blood volume in CT perfusion imaging. CT perfusion imaging was equivalent to SPECT in accuracy, and superior in spatial resolution. CT perfusion imaging is likely to become more widely available as an easy-to-perform technique for assessing cerebral perfusion in a patients with moyamoya disease.

Characteristics of aneurysms of the internal carotid artery bifurcation.

SummaryBackground. Arterial bifurcations are sites of maximal hemodynamic stress, where cerebral aneurysms commonly develop. However, in our experience with endovascular treatment for aneurysms of the internal carotid artery (ICA) bifurcation, we often experienced that the aneurysmal neck did not necessarily exist only at the ICA bifurcation (ICBi). In this study, we have retrospectively evaluated characteristics of aneurysms at the ICBi.Methods. Ten ICBi aneurysms in 10 consecutive patients were studied retrospectively. The size of the aneurysms, the angles formed between the ICA and the anterior cerebral artery (ACA) and middle cerebral artery (MCA), and the diameter of the ICA, ACA and MCA were measured. Furthermore, to study the relationship between the location of the aneurysmal neck and the bifurcation of the ICA, the distance between the midline of the aneurysmal neck and of the ICA was measured.Results. The average aneurysm size was 6.3 ± 3.2 mm and the average neck was 3.1 ± 1.2 mm. The average ICA-ACA angle was 57.3 ± 16.5 degrees, and the average ICA-MCA angle was 128.9 ± 24.1 degrees. The average diameters of the ICA, ACA and MCA were 2.9 ± 0.5 mm, 1.9 ± 0.4 mm and 2.5 ± 0.4 mm, respectively. The average distance between the midline of the aneurysmal neck and the ICA was 1.6 ± 0.6 mm, and all aneurysmal necks of the ICBi arose from the side of the ACA.Conclusion. ICBi aneurysms were deviated to the side of the A1 segment of the ACA, where the artery might suffer higher hemodynamic stress.

Churg-Strauss syndrome presenting with subarachnoid hemorrhage from ruptured dissecting aneurysm of the intracranial vertebral artery

Churg-Strauss syndrome (CSS) represents a rare systemic vasculitis that is almost invariably accompanied by bronchial asthma and eosinophilia. We report a case of a 36-year-old woman with previously diagnosed CSS presented with subarachnoid hemorrhage (SAH) from dissecting aneurysm in a vertebral artery (VA). Two months before onset of SAH, the patient had presented with numbness on her right lower leg due to peripheral neuropathy. On admission, angiography revealed dissecting aneurysm of the right intracranial VA and stenosis of the basilar artery. Hematological examination revealed an increased percentage of eosinophils. Ruptured dissecting aneurysm of the intracranial VA was diagnosed. Emergent coil embolization of the dissecting aneurysm and occlusion of the parent artery was performed to prevent repeated hemorrhage from the dissecting aneurysm. Then pharmacotherapy with prednisone was initiated for CSS. The patient recovered well and was discharged without any neurological deficit. As far as we know, this is the first reported case of CSS presented with SAH from dissecting aneurysm on posterior circulation.

The Pharmacokinetics and Pharmacodynamics of Meropenem in the Cerebrospinal Fluid of Neurosurgical Patients

Abstract This study examined the pharmacokinetics and pharmacodynamics of meropenem in cerebrospinal fluid (CSF). Meropenem (0.5 g every 8 h) was administered by 0.5-h infusion to six neurosurgical patients. Lumbar CSF and venous blood samples were obtained at 0.5-16 h after the start of the first infusion. Drug concentrations in the CSF and plasma were analyzed pharmacokinetically and used for a Monte Carlo simulation with the minimum inhibitory concentration (MIC) data of clinical isolates in Japan. Meropenem penetrated into the CSF with the area under the drug concentration-time curve ratio of 0.10 ± 0.03 (mean ± SD) and the repeated infusions caused the drug concentration in the CSF to accumulate slightly. Against Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, and Escherichia coli isolates, 0.5 g q8h achieved a >90% probability of pharmacodynamic target (50% of the time above MIC) attainment, and 1 g q8h was needed for a >90% probability of target (100% of the time above MIC) attainment. However, against Pseudomonas aeruginosa, 2 g q8h achieved a lower probability of target attainment. These results should help us to better elucidate the pharmacokinetics of meropenem in the cerebrospinal space while also helping us to choose the appropriate drug dosages for the management of bacterial meningitis.

Carotid artery stenting in a patient with right-sided aortic arch with an aberrant left subclavian artery

A right-sided aortic arch with an aberrant left subclavian artery is a rare anatomical variation. We report a case treated with carotid artery stenting (CAS) for a patient with a right-sided aortic arch with an aberrant left subclavian artery. A 72-year-old man presented right hemiparesis due to acute brain infarction. Neck CT angiography showed 70% stenosis in the left internal carotid artery (ICA). We diagnosed acute brain infarction as artery-to-artery embolism due to ICA stenosis and decided to perform carotid artery stenting (CAS) for symptomatic ICA stenosis. CT angiography to evaluate an access route to the lesion incidentally showed the right-sided aortic arch with an aberrant left subclavian artery. An intraoperative aortogram showed a right-sided aortic arch. The guiding catheter was carefully introduced up to the left common carotid artery. CAS was performed with a proximal balloon and distal filter protection. The stenotic area was restored, and the patient was discharged without suffering recurrent attacks. Although a right-sided aortic arch with an aberrant left subclavian artery is a very rare anatomical variation, it can be encountered in neuroendovascular treatment, and therefore knowledge of this anatomical variation is important.

Course of apparent diffusion coefficient values in cerebral edema of dural arteriovenous fistula before and after treatment.

Apparent diffusion coefficient (ADC) values at magnetic resonance imaging (MRI) are useful to distinguish vasogenic and cytotoxic edema due to cerebovascular diseases. Dural arteriovenous fistulas (DAVFs) with retrograde leptomeningeal venous drainage may cause cerebral edema by venous congestion. We report herein the course of ADC values of cerebral edema before and after endovascular treatment in DAVFs. A 65-year-old woman with transverse-sigmoid (T-S) sinus DAVFs with retrograde leptomeningeal venous drainage presented with severe edema in cerebellar hemisphere and brainstem. In preoperative MRI, increased ADC values were observed in the edema area. The isolated sinus was obliterated completely by transvenous embolization. On the following day after treatment, the ADC values in cerebral edema area increased slightly without any new neurological deficits and improved at 1 week later. Rapid resolution of venous congestion due to DAVFs may cause a slight, transient progression of vasogenic edema.

Single-stage operation for a giant haemangiopericytoma following intracranial feeder embolization

Meningeal haemangiopericytomas (HPC) are malignant intracranial neoplasms that commonly recur and metastasize. Large size at diagnosis, abundant intracranial feeders and the risk of intraoperative bleeding can make them difficult to completely remove in one operation. We report here a rare case of a giant HPC which was treated successfully using a one-stage operation following superselective intracranial feeder occlusion. A 30-year-old man presented with a left middle cranial fossa tumour extending to the left temporal lobe and cerebellar tentorium. Angiography revealed supply from a dilated left posterior temporal artery branching from the posterior cerebral artery. The tumour was totally removed in a single-stage excision after embolization of the intracranial major feeding artery. The present case suggests the usefulness of preoperative embolization for HPC, particularly of intracranial feeders, to achieve total resection safely in a single operation.

Evaluation of dural arteriovenous fistulas of cavernous sinus before and after endovascular treatment using time-resolved MR angiography

Digital subtraction angiography (DSA) is the preferred method for confirming dural arteriovenous fistulas (DAVFs), but it has the disadvantage of being invasive. In contrast, time-resolved magnetic resonance angiography (TR-MRA) is a useful, noninvasive imaging technique. The aim of this study was to compare the evaluation of DAVFs of the cavernous sinus (CS) using TR-MRA and DSA. TR-MRA and DSA were obtained in six patients with CS-DAVFs treated with endovascular surgery. TR-MRA and DSA before and after treatment were reviewed by one neuroradiologist without previous knowledge of the existence of CS-DAVFs for the detection and characterization (feeding artery and venous drainage) of CS-DAVFs. DSA showed six CS-DAVFs in the six patients. TR-MRA demonstrated a hyperintensity area in the CS at the arterial phase in six patients. DSA revealed feeding arteries and a drainage vein in all CS-DAVFs. In contrast, the feeding arteries could not be identified with TR-MRA. The details regarding venous drainage could only be speculated upon with TR-MRA as it was only partly visible on the TR-MRA images. DSA after embolization showed no CS-DAVFs in any of the six patients. TR-MRA showed no hyperintensity areas in the CS at the arterial phase in any of the six patients, and with no coil artifacts. In summary, TR-MRA could detect and diagnose CS-DAVF. However, the detail regarding anatomical feeders and draining veins remains poorly visualized by TR-MRA. In this small number of cases, TR-MRA can be a useful screening tool to detect CS-DAVF and possibly also to confirm persistent obliteration following definitive treatment.