Hiromu Hadeishi

Glasgow Coma Scale in the prediction of outcome after early aneurysm surgery.

OBJECTIVE A prospective study was performed to analyze whether the Glasgow Coma Scale (GCS) was useful in predicting the outcome after early surgical intervention for aneurysmal subarachnoid hemorrhage (SAH). METHODS In a consecutive series of 765 patients who underwent surgery for aneurysms within 7 days after SAH, the level of consciousness was assessed by the GCS just before surgery and the outcome was graded by the Glasgow Outcome Scale 6 months after surgery. RESULTS The patient distribution in accordance with the GCS sum scores in descending order from 15 to 3 was as follows: 334, 140, 58, 27, 20, 26, 27, 19, 26, 17, 20, 27, and 24 patients, respectively. In general, the higher the preoperative GCS score was, the better the surgical outcome was. The overall surgical result was significantly correlated with the preoperative GCS score (rs = 0.615, P < 0.001). With respect to the levels that distinguish the outcome along the GCS axis, a significant difference in the outcome was observed only between the GCS scores of 15 and 14 (P < 0.001, Wilcoxon test). CONCLUSION The GCS proved useful in the preoperative evaluation of patients with SAH, in terms of outcome prediction. It is suggested that the SAH scale proposed by the World Federation of Neurosurgical Societies be reexamined, because differences in outcomes were not clear between the GCS scores of 13 and 12 or between those of 7 and 6, in which Grades III and IV and Grades IV and V are differentiated in the scale, respectively.

Diffusion-weighted magnetic resonance imaging in patients with subarachnoid hemorrhage.

OBJECTIVE To evaluate the occurrence and distribution of direct brain injury caused by acute subarachnoid hemorrhage (SAH) by the use of magnetic resonance imaging. METHODS Computed tomography and magnetic resonance imaging, including diffusion-weighted imaging (DWI), were performed in 32 patients with SAH by use of a 1.5-T whole-body superconductive scanner equipped with an echo planar imaging system. In all cases, computed tomographic and magnetic resonance imaging scans were obtained at the time of admission, before angiography and surgical intervention. RESULTS No abnormalities were revealed by DWI in any of the low-grade SAH patients. However, five (71%) of seven patients diagnosed as having poor-grade SAH (World Federation of Neurosurgical Societies Grades 4 and 5) displayed multiple, patchy focal abnormalities on DWI. Computed tomographic scans obtained at admission failed to clearly demonstrate all of the damaged areas of the brain that were visualized by DWI. These lesions were located in supratentorial cerebral parenchyma, but not in the thalamus, basal ganglia, or cerebellar hemisphere. These multiple widespread lesions exhibiting laminar involvement of the cerebral cortex were not associated with the site of the ruptured aneurysm. CONCLUSION DWI revealed widespread multifocal lesions in the cerebral cortex of acute poor-grade SAH patients. DWI provides accurate images of all areas of brain damage directly attributable to SAH.

Morbidity and mortality from surgical treatment of unruptured cerebral aneurysms at Research Institute for Brain and Blood Vessels-Akita.

OBJECTIVE:Although the necessity of craniotomy for an unruptured cerebral aneurysm (UCA) is controversial, surgery is warranted if surgical risks are less than the risks of natural history. In this study, we investigated the need for craniotomy for UCAs on the basis of surgical risk. METHODS:History of cerebrovascular disorders, aneurysm site and size, surgical complications, and clinical outcome were investigated in 368 patients (134 men, 234 women; ages 31–79 yr) who underwent craniotomy for treatment of UCA at our institute between 1993 and 2000. RESULTS:We investigated 549 aneurysms. The mean size was 6.0 mm. Sites affected were the anterior cerebral artery (101 aneurysms), internal carotid artery (224 aneurysms), middle cerebral artery (201 aneurysms), and vertebrobasilar artery (23 aneurysms). The most common previous cerebrovascular disorders were subarachnoid hemorrhage (58 patients, 15.8%) and cerebral infarction (41 patients, 11.1%). Eight patients experienced permanent neurological deficits, for a total morbidity of 2.2%. One patient died, for a total mortality of 0.3%. For UCAs less than 10 mm in size, the morbidity was 0.6% and the mortality was 0%. For UCAs greater than 10 mm in size, the morbidity was 6.1% and the mortality was 1.2%. For UCAs in the anterior cerebral artery or middle cerebral artery, the morbidity was 0.3%. Temporary deficits were more frequently observed in patients older than 70 years of age than in patients 70 years of age or less. CONCLUSION:Surgical treatment is a viable alternative for patients 70 years of age or less with UCAs less than 10 mm in size or UCAs located in the anterior cerebral artery or middle cerebral artery, because the surgical risk of treating such UCAs is sufficiently lower than the annual rupture rate of UCAs (2.3%) and the mental stress suffered by patients with untreated UCAs.

Mastoid canal and migrated bone wax in the sigmoid sinus : Technical report

A study of the migration of bone wax into the sigmoid sinus through the mastoid canal is reported here. In 7 of 161 patients who underwent retromastoid craniectomy, the postoperative soft tissue window image computed tomographic scans demonstrated a hypodense mass in the ipsilateral sigmoid sinus. The density value of the hypodense mass ranged from -34 to -79 Hounsfield units, which was neither as low as that of air nor as high as that of cerebrospinal fluid, but was comparable to that of fat tissue or bone wax. The continued presence of all of these masses in the sigmoid sinus was confirmed 1 month to 2 years after surgery. These computed tomographic findings suggested that this abnormal hypodense mass might be a migrated fragment of the bone wax that had been used for the control of venous bleeding from the mastoid emissary vein, because each of the seven affected patients had a large mastoid foramen and a large quantity of bone wax had been needed to control the bleeding during retromastoid craniectomy. No other material with the potential to migrate into the sigmoid sinus had been applied as a packing material. In two of the seven patients, venous magnetic resonance angiography after surgery demonstrated that the ipsilateral sigmoid sinus was not patent and the computed tomographic scans also revealed that the hypodense masses occupied the sigmoid sinus. It is concluded that the intrasurgical application of a large quantity of bone wax to control the bleeding from the large emissary veins carries a risk of the migration of bone wax into the sigmoid sinus.(ABSTRACT TRUNCATED AT 250 WORDS)

Local application of calcium antagonists inhibits intimal hyperplasia after arterial injury.

The local effect of the calcium channel antagonist diltiazem and the protein kinase inhibitor 1-5-(isoquinoline sulfonyl)-5-homopiperazine HCL (HA1077) on neointimal formation after arterial injury were investigated by the use of a perivascular drug-delivery system. Bilateral carotid artery balloon injury was produced in 130 rats. In six groups of 10 rats each, diltiazem or HA1077 at three doses (low, 0.2 mg; medium, 1 mg; high, 5 mg) was mixed with the drug-delivery polymer poly(vinyl) alcohol and applied to the adventitial surface of the injured right carotid artery enclosed by a Silastic cuff; 10 control animals received polyvinyl alcohol only in the silastic cuff. In all animals, the contralateral injured artery without the cuff served as a control. At 10 and 20 days after the injury, the intimal cross-sectional area was determined from light microscopic sections for the injured segment of both carotid arteries. In six additional groups of 10 rats each, treated as above, levels of diltiazem and HA1077 in plasma were measured at periods from 1 hour to 5 days after perivascular application. At 10 days after endothelial injury, animals receiving high-dose diltiazem or HA 1077 (5 mg) demonstrated significant reductions in neointimal area compared with polyvinyl alcohol controls for both treated and contralateral untreated vessels. At 20 days after injury, neointimal hyperplasia was inhibited only on the treated side in both high-dose groups. Perivascular diltiazem and HA1077 at lower doses (1 or 0.2 mg) did not affect neointimal area at 10 or 20 days in either treated or untreated arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Carotid artery resection: preoperative temporary occlusion is not always an accurate predictor of collateral blood flow.

Conclusion The morbidity predicted by means of preoperative PET studies does not always correlate with the morbidity experienced after permanent carotid artery occlusion. A pre-resection extracranial–intracranial bypass may be necessary to reduce the risk of neurologic morbidity, in particular when carotid artery resection is planned for tumors involving the skull base. Objectives Carotid artery resection is generally considered the only curative treatment for patients with advanced head and neck carcinoma involving the carotid artery. PET can be used during temporary occlusion of the internal carotid artery to assess the safety of the procedure. The aims of this paper were to clarify the risk of carotid artery resection and the benefit of extracranial–intracranial bypass. Material and methods Twelve patients diagnosed with head and neck cancer adherent to the carotid artery and in proximity to the skull base who had shown good hemispheric collateral blood flow by means of PET underwent carotid artery resection without preoperative bypass. Results Of the 12 patients who underwent carotid artery resection without reconstruction, 10 suffered no serious neurologic complications; however, 2 suffered cerebral infarctions intraoperatively.

Cerebral blood flow and oxygen metabolism in hemiparetic patients with chronic subdural hematoma: Quantitative evaluation using positron emission tomography

BACKGROUND It remains unclear why chronic subdural hematoma (CSH) can cause hemiparesis, although the contribution of impaired cerebral blood flow and metabolism has been suggested. METHODS We studied six hemiparetic patients (five men, one woman; mean age 60.5 +/- 7.5 years) with unilateral CSH using positron emission tomography. The 15O2 steady state technique was used to measure regional cerebral blood flow (rCBF), regional oxygen extraction fraction (rOEF), and regional cerebral metabolic rate of oxygen (rCMRO2), followed by the 1-minute inhalation of C15O to measure regional cerebral blood volume (rCBV). RESULTS On the hematoma side, rCBF and rCMRO2 were significantly reduced in the caudate nucleus and the cingulate gyrus. We observed a tendency toward reduced levels of rCBF and rCMRO2 in the lentiform nucleus. rCBV was not elevated. rOEF was significantly elevated in the lentiform nucleus, the cingulate gyrus, the frontal gray matters under the hematoma and the semioval center. On the nonhematoma side, rCBF and rCMRO2 were normal except for the significant reduction in the cingulate gyrus. rCBV was elevated in the lentiform nucleus, the middle temporal gyrus and the inferior frontal gyrus. rOEF was elevated significantly in the cingulate gyrus, the precentral gyrus and the semioval center. CONCLUSIONS Our hemiparetic patients with CSH were observed to have a circulatory disturbance of blood; it was manifested by an elevation of rOEF, specifically in the hemisphere adjacent to the hematoma. This circulatory disturbance was highly pronounced and resulted in a consistent reduction in rCBF and rCMRO2 in the anterior central cerebral area such as the caudate nucleus, the lentiform nucleus and the cingulate gyrus.

Multiple medullary venous malformations decreasing cerebral blood flow: Case report

A rare case of multiple medullary venous malformations in the right cerebral hemisphere is reported. The literature review yielded only one case of multiple medullary venous malformations. Computed tomography scan showed multiple calcified lesions with linear contrast enhancement representing abnormal dilated vessels and mild atrophic change of the right cerebral hemisphere. Single-photon emission computed tomography using N-isopropyl-p-(123I) iodoamphetamine demonstrated decreased cerebral blood flow in the right cerebral hemisphere.

Fatal Hemorrhage in Cerebral Proliferative Angiopathy

Cerebral proliferative angiopathy (CPA) is a rare vascular abnormality with several angiomorphological features that are distinct from brain arteriovenous malformations (AVMs). The natural history of CPAs indicates a lower risk for hemorrhage compared to brain AVMs. A 62-year-old woman presented with gait instability and dysarthria. MRI and angiography revealed a diffuse vascular network involving the tectum and cerebellar vermis with intermingled brain parenchyma. This lesion had no dominant feeder, high-flow arteriovenous shunt, flow-related aneurysm or highly dilated veins on angiogram. These findings were consistent with a diagnosis of CPA. During follow-up, she developed progressive gait instability and eye movement abnormalities, but no remarkable change was detected on the repeated MRI and angiography. Nine years later, she died of mesencephalic hemorrhage originating from the CPA. To the best of our knowledge, this is the first description of a patient with CPA who died as a result of the initial hemorrhage. It is important to recognize that a part of CPAs is aggressive and can be more vulnerable to critical hemorrhage.

Post-operative changes of cerebral circulation and metabolism in the acute stage of low-grade aneurysmal subarachnoid hemorrhage

Abstract Objective: Pre- and post-operative cerebral circulation and metabolism were evaluated in patients with low-grade acute aneurysmal subarachnoid hemorrhage (SAH) who underwent early surgery to investigate the effects on brain dysfunction. Methods: Positron emission tomography (PET) was performed to measure the regional cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF) and cerebral blood volume in four patients (one male and three females, mean age: 60.3 years) with low-grade SAH within 30 hours of onset. Post-operative PET was performed on the seventh post-operative day. No patient suffered clinical deterioration during the study. Pre-operative PET scans demonstrated significant global reduction of CBF and CMRO2, compared to 16 normal control subjects, and no significant change in OEF. CBF and CMRO2 reduction post-operatively improved to the normal control values. Post-operative OEF was significantly increased compared to the normal control value. Conclusions: Patients with low-grade SAH have impairment of cerebral circulation and metabolism in the acute period, which improves after surgery. Early surgery for low-grade SAH, necessary to avoid rerupture of the aneurysm, did not worsen the impairment of cerebral circulation and metabolism. However, measures to protect the brain from perioperative damage are necessary to achieve the optimum outcome.