The value of acetazolamide challenge test in the evaluation of acute stroke.

The acetazolamide (ACZ) challenge test provides a useful information about compromised hemodynamic state in chronic stroke. However, there is no consensus whether this test is of any value in the evaluation of acute ischemic stroke. The purpose of this study is to examine the value of ACZ challenge test in the management of acute ischemic stroke. Study 1: Nineteen patients with acute embolic stroke were subjected to the Xe CT with and without ACZ (17 mg/kg, i.v.) within 6 hours from the onset. The cases included 12 middle cerebral artery (MCA) occlusions and 7 internal carotid artery (ICA) occlusions. The baseline cerebral blood flow (CBF) values and cerebrovascular reserve (CVR) (% increase in CBF after ACZ) were analyzed in 53 affected regions of interest (ROI). The study indicated that the CBF threshold of subsequent permanent infarction was 15 ml/100 g/min and the ROI with negative CVR had a higher incidence of hemorrhagic infarction. Study 2: Xe-CT with and without ACZ was performed in 32 patients with acute occlusion of the main trunks of cerebral arteries within 6 hours after the onset. Occluded arteries were MCA in 20 patients, ICA in 7, both ICA and MCA in 4 and anterior cerebral artery (ACA) in one. The abnormal hemispheric CBF (< 20 ml/100 g/min) and CVR (< 10%) were correlated with the Glasgow outcome scales of the patients. The predictability of Good Recovery, Moderately Disabled, Severely Disabled, Vegetative Survival and Dead were 80%, 50%, 50%, 100% and 100% by CBF criteria, and 80%, 60%, 80%, 100% and 100% by CVR criteria, respectively. There was no significant increase in the predictability of final outcome of the patients by adding the CVR information of the acute stage. The ACZ challenge test has a potential value in the prediction of hemorrhagic transformation of the ischemic regions. It does not increase the predictability of the long-term outcome. We do not recommend performing ACZ challenge test on routine basis in the evaluation of acute ischemic stroke.

The regional cerebral blood flow amelioration of argatroban in the acute stage of cerebral thrombosis.

Cerebral blood flow changes by argatroban in the acute stage of cerebral thrombosis have been investigated with the use of stable xenon computed tomography (Xe/CT). The study group consisted of 14 cases (7 males, 7 females) with the average age of 59 years old (ranging from 21 to 79 years of age). We evaluated the cerebral blood flow change after an intravenous drip infusion of 10 mg of argatroban. After the administration of argatroban, we recognized a significant increase in the blood flow (24.4 +/- 5.0 ml/100 g/min to 28.4 +/- 2.7 ml/100 g/min, p < 0.05) in the blood flow area of lower than 30 ml/100 g/min in the affected vascular territory. As a conclusion, we found that argatroban improves ischemic symptoms through the amelioration of blood flow in the penumbra area.

Use of a split dura for revascularization of ischemic hemispheres in moyamoya disease.

A new technique of indirect revascularization using the dural arterial supply to provide donor vessels is presented together with the results of an assay performed to determine the angiogenic activity of the dura. At surgery, a portion of the dura near the branches of the middle meningeal artery was split into outer and inner layers, and the split surface of the outer layer was attached to the cortical surface. This procedure, combined a with standard encephaloduroarteriosynangiosis, was applied to 25 hemispheres in 18 patients with pediatric moyamoya disease (mean age 6 years). All of the patients were symptom free by 1.5 years after surgery. The follow-up period ranged from 1 to 12 years (mean 6.5 years). Thirteen (81%) of 16 patients were able to lead normal lives and three were mildly handicapped due to mental retardation that existed preoperatively. Postoperative superselective angiograms demonstrated effective cortical revascularization through the dural arteries as well as from the scalp arteries. A histological study of the dura in cases of moyamoya disease showed an increased number of blood vessels in the outer layer. Angiogenic activity determined by chorioallantoic membrane assay was higher in the split surface of the dura than in the internal surface of the dura (the natural interface between the dura and cortex). The split duroencephalosynangiosis described in this report is a useful addition to indirect revascularization techniques, allowing extension of the area of revascularization in the ischemic hemispheres of patients with moyamoya disease.

Comparison of Xe-CT/CBF and quantitative ECD-SPECT.

We compared stable xenon enhanced X-ray computed tomography (Xe-CT) with Technetium-99m ethylsteinate dimer single-photon emission computed tomography (ECD-SPECT) in 12 patients. We evaluated the cerebral blood flow (CBF) values in the territory of the anterior, middle and posterior cerebral artery, and in the thalamus. The CBF values were higher in ECD-SPECT than in Xe-CT except for the values of the thalamus. The posterior cerebral artery territory showed a lower correlation and the thalamus had no correlation between two methods. We discussed causes of these differences.

Surgical modulation of the natural course of collateral circulation in chronic ischemic patients.

The purpose of this study was to evaluate hemodynamic compromise in terms of baseline CBF and CRC in patients with chronic cerebral occlusive lesions and its modulation by a superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The study subjects were 10 healthy volunteers and 49 chronic ischemic patients with stenosis or occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA). The hemodynamics were measured using stable xenon enhanced computed tomographic CBF measurement with the acetazolamide challenge. The compromised hemodynamics in patients with chronic steno-occlusive lesions did not improve during their natural course after two months. STA-MCA bypass modulated hemodynamic compromise in the ischemic patients. We recommend STA-MCA bypass for patients with reduced CRC, regardless of whether baseline CBF is reduced or normal. Hemodynamic classification using a combination of baseline CBF values and CRC values is useful for evaluating cerebral hemodynamics and for choosing the best treatment for cerebral ischemia with occlusive lesions.

Effects of acute percutaneous transluminal recanalization on cerebral embolism.

The effects of percutaneous transluminal recanalization (PTR) on critical hemodynamics of cerebral embolism were studied using stable xenon-enhanced computed tomography in patients within 6 hours after onset. PTR was conducted in 10 cases (PTR group) and not conducted 8 cases (non-PTR group). The development of infarction was followed by CT scan. In the cortical arterial regions, the lowest cerebral blood flow (CBF) value in regions of interests (ROIs) without development of infarction was 12.9 ml/100 g/min in the PTR group and 17.0 ml/100 g/min in the non-PTR group. In ROIs with a cerebrovascular reserve capacity (CRC) less than 0 ml/100 g/min, even with a CBF greater than 12.9 ml/100 g/min, 3 of 4 ROIs underwent cerebral infarction. PTR conducted within 6 hours after onset of cerebral embolism would prevent the cortical regions with a CBF greater than 12.9 ml/100 g/min and with a CRC greater than 0 ml/100 g/min from undergoing cerebral infarction.

Brain metastasis of testicular tumor with massive hemorrhage--report of two cases.

The authors report two cases of brain metastasis from testicular tumor with massive, sudden intratumoral hemorrhage. In both cases, the hemorrhage occurred during the 1st admission day and carried a high risk of fatality. Early, aggressive surgical removal is advisable before general deterioration. Postoperative chemotherapy with an agent different from the one applied to primary lesion is also recommended because of drug tolerance.

[One pedigree of "moyamoya" disease].

One familial case of "moyamoya" disease affecting three patients is reported. The patient in Case 1 was a 28-year-old female. She had suffered from motor weakness of the right limbs in her infantile period. She visited our hospital because of sudden headache and left motor weakness associated with nausea and vomiting. On admission, CT scan revealed cerebral hemorrhage in the right caudate nucleus with intraventricular clots and infarction in the left parietal lobe. Angiography showed stenosis of the left ICA terminal portion and occlusion of the right side, with moyamoya vessels in the basal area. The patient in Case 2 was a 54-year-old female, who was the mother of Case 1. After an operation for acute upper intestinal bleeding, she suffered from cerebral infarction. CT scan revealed large low density areas in the territory of the bilateral MCA. Angiography showed stenosis of the bilateral ICA terminal portions, occlusion of the right MCA, stenosis of the left MCA, and moyamoya vessels in the basal area. The patient in Case 3 was a 40-year-old female, who was a younger sister of Case 2. She had a convulsive attack in her infantile period. She visited our hospital because of gradually worsening headache. CT scan revealed multiple infarctions in the left paraventricle, the right parieto-occipital and occipital lobe. Angiography showed occlusion of the bilateral ICA terminals with moyamoya vessels in the basal and the ethmoidal areas. The patient in Case 2 died immediately. Surgery for reconstruction of hemodynamics was performed in Case 1 and 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Limitation of CT in diagnosis of pancreatic cancer.

The differentiation of pancreatic abnormalities remains a problem. We analyzed the sensitivity and specificity of computed tomography (CT) in the diagnosis of pancreatic disease, using six radiologists who had less than six months' training in CT (resident level: inexperienced) and six who had more than 12 months' training (staff level: experienced) in order to clarify the difficulty with CT in the qualitative diagnosis of pancreatic cancer. We reviewed retrospectively 100 cases: 28 cases of pancreatic cancer, 15 of chronic pancreatitis, three of acute pancreatitis, 12 of neoplastic disease that involved the pancreas, and 42 normal subjects. The average sensitivity and specificity of CT in the diagnosis of pancreatic disease were 81.3% and 84.4%, respectively, for the experienced radiologists and 64.0% and 82.1%, respectively, for the inexperienced radiologists. The averages for pancreatic cancer were 65.3% and 87.8% for the experienced radiologists and 60.7% and 87.3% for the inexperienced radiologists. We conclude that the ability to detect pancreatic abnormalities improves with training and experience, but diagnosis of pancreatic cancer does not improve after a certain level of expertise.

Cerebral sparganosis mansoni. Report of two cases.

Among diseases due to cerebral parasitism, that caused by Sparganum mansoni, the larva of Spirometra mansoni, is very rare. We have encountered two such cases. A computed tomography scan in both revealed a nodular high density contrast enhanced area against an extensive low density background area. Neither calcification nor cyst formation was recognized. These computed tomography scan findings were thought to be characteristic for cerebral sparganosis mansoni and were difficult to differentiate from those of a cerebral tumor. In both cases, definitive diagnosis was achieved by identification of the worm after excision of the lesion. The best treatment for cerebral sparganosis mansoni is surgical excision of the lesion, and in the two cases presented the postoperative outcome was good.

Multiple meningiomas of the spinal canal and posterior fossa--case report.

The majority of multiple meningiomas are associated with von Recklinghausen's disease, and those that are not, i.e., true multiple meningiomas, particularly with simultaneous development in the posterior fossa and spinal canal, are very rare. We recently encountered a case of true multiple meningiomas in which the lesions were found simultaneously in the left posterior fossa and the upper thoracic spinal canal. The spinal meningioma consisted mainly of meningotheliomatous components, and that in the posterior fossa of fibroblastic components. Both tumors were surgically removed. The cause of the multiplicity in cases of true multiple meningiomas is unknown. Incidental multiplicity is a consideration when the number of tumors is relatively small. Spinal meningiomas are often undetected in the absence of neurological symptoms. However, even if von Recklinghausen's disease is not present, and particularly when more than two meningiomas have been discovered, the patient must be carefully examined for other tumors.

[Cerebral sparganosis mansoni--report of two cases].

Cerebral Sparganosis Mansoni is a very rare disease caused by a larva of Diphyllobothrium and so far, only two cases have been reported. Another two cases are presented in this paper. Case 1: A 64-year-old man was admitted presenting with hypovolition. He has eaten thunder fishes several years before. CT scan revealed an extensive low density area with an enhanced nodular mass around the right basal ganglia. An operation was carried out on the preoperative diagnosis of brain tumor and a granuloma was completely removed. His postoperative course was excellent. The histological examination confirmed the diagnosis of cerebral sparganosis. Case 2: The patients was 60-year-old male showing hypesthesia in the left half of his face. He has often been to South Korea where patients of Sparganosis Mansoni are often reported. Enhanced CT scan demonstrated a small nodular region in the tip of the left temporal lobe. Sparganum Mansoni was identified during surgery and a granuloma was also extirpated. His postoperative course was also excellent. In cases with cerebral parasitism by Sparganum Mansoni, CT scan shows an extensive low density area with a nodular enhancement, but no calcification nor cyst formation. It is quite difficult to differentiate sparganosis from cerebral tumors on CT and laboratory data preoperatively. The diagnosis is usually confirmed by postoperative histological examination. As for the treatment of this disease, no effective chemotherapy is now available and surgical excision is recommended. Actually, four cases with cerebral sparganosis including two of our own demonstrated a satisfactory prognosis by surgical treatments.

[A case of iatrogenic traumatic intracranial aneurysm].

A case of traumatic aneurysm due to an arterial injury during removal of a tuberculum sellae meningioma is reported. A 43-year-old man had undergone craniotomy for removal of the tumor. It was very hard with many feeders from bilateral anterior cerebral arteries (ACA), so the resection between the left ACA and the tumor was difficult. A small artery was accidentally pulled out from the left ACA and bleeding occurred from the small artery in the artery. The ACA was trapped temporarily with two clips and was coated using Oxycell and Biobond. The bleeding was stopped by this procedure and the blood reflowed. This tumor was removed totally, but postoperative CT scan showed an enhancing small lesion in the anterior part of the left basal ganglia 10 days after operation. The angiograms performed next day revealed a fusiform aneurysm of the left proximal ACA near the anterior communicating artery. The skull was reopened to treat the aneurysm. The aneurysm arising from just a bleeding point in the previous operation was oval in shape without neck, so it was trapped by two small aneurysm clips and resected. The patient's condition was uneventful after the second operation. Pathological diagnosis of the aneurysm was confirmed a false aneurysm. Iatrogenic traumatic aneurysms caused by neurosurgical procedure has been reported in 29 cases. Eighteen cases showed bleeding from injured artery during surgery and a half of them showed rupture from the aneurysm within one month after operation. Such doubtful cases of traumatic aneurysm should be diagnosed by angiography and operated as early as possible.

Computed tomography and angiography in MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes); report of 3 cases.

Among mitochondrial encephalomyopathies, MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes, Pavlakis et al. 1983) is recognized as a distinct syndrome characterized by generalized convulsions and recurrent stroke-like episodes. The neuroradiological findings of three patients with MELAS are reported here. Retrospective review shows that MELAS should be included in the differential diagnosis of infarct-like lesions of the cerebrum.