Treatment of intradural paraclinoidal aneurysms.

Intradural paraclinoidal aneurysm still presents conceptual confusion and technical surgical problems. The clinical features of 68 consecutive patients with paraclinoidal aneurysms were analyzed. The pterional approach was used in all patients. Subarachnoid hemorrhage (SAH) occurred in 37 patients from the paraclinoidal aneurysm and in 10 patients from another associated aneurysm. Thirty-four of the 37 ruptured paraclinoidal aneurysms were clipped, two blister-like aneurysms required trapping, and one blister-like aneurysm was coated. Thirteen of the 31 unruptured paraclinoidal aneurysms, consisting of 10 with ruptured associated aneurysm, four symptomatic, and 17 incidental, were clipped and 18 were coated. Favorable outcomes were obtained in 38 of 47 patients with SAH and 17 of 21 patients without SAH. Nine unfavorable outcomes in SAH patients were caused by primary brain damage (5), vasospasm (2), cerebral infarction after trapping (1), and pneumonia (1). All four unfavorable outcomes in non-SAH patients were due to surgical procedures for giant aneurysms or associated basilar artery aneurysm. Removal of the anterior clinoid process was performed to secure the proximal neck in 15 patients with large or giant aneurysms. Multiple clips with or without fenestrated clips were required in all giant aneurysms, and exposure of the cervical internal carotid artery (ICA) in 17 giant or large aneurysms. Fenestrated clips were also useful for one small aneurysm projecting posteriorly. A favorable outcome was achieved in 17 of 19 patients undergoing coating. Coating without clipping might be better for some blister-like ICA aneurysms, even if ruptured. Paraclinoidal aneurysms can be clipped with favorable results using these techniques except for giant aneurysms and associated basilar artery aneurysm.

Clinical features of relative focal hyperfusion in patients with intracerebral hemorrhage detected by contrast-enhanced xenon CT.

BACKGROUND AND PURPOSE: The prevalence and clinical features of relative focal hyperperfusion were investigated in 165 consecutive patients with intracerebral hemorrhage. METHODS: Contrast-enhanced xenon CT was used to observe regional cerebral blood flow in all patients (86 men and 79 women ranging in age from 25 to 89 years; mean age, 66 years). The clinical data of patients with and without relative focal hyperperfusion were compared to define distinguishing characteristics. RESULTS: Relative focal hyperperfusion was observed in 24 (23.5%) of 102 patients in the acute stage but in no patient in the subacute or chronic stages. Relative focal hyperperfusion was associated significantly more often with putaminal and subcortical hemorrhage than with thalamic and cerebellar hemorrhage. We found that patients with relative focal hyperperfusion had a lower mean age than those without it; a male dominance; and a more common history of intracerebral hemorrhage. CONCLUSION: Relative focal hyperperfusion occurs in the acute stage after intracerebral hemorrhage and does not persist for more than 30 days. The most common locations are the putamen and subcortical areas. Risk factors include male sex and previous bleeding in the same area.

Discrepancies in brain perfusion SPECT findings between Tc-99m HMPAO and Tc-99m ECD: evaluation using dynamic SPECT in patients with hyperemia.

Discrepancies have been reported between the findings of Tc-99m HMPAO and Tc-99m ECD brain perfusion SPECT imaging. This study investigated the discrepancies in the accumulation of these tracers using dynamic SPECT to detect the super early phase of distribution. Thirteen patients with luxury perfusion or high flow states were studied with both dynamic and standard SPECT using Tc-99m HMPAO and Tc-99m ECD within 1-3 days. Standard SPECT showed discrepancies in 6 of 13 patients. Patients with meningioma and cerebral thrombosis had increased accumulation of Tc-99m HMPAO and decreased uptake of Tc-99m ECD. Patients with arteriovenous malformation, subarachnoid hemorrhage, and cavernous angioma had decreased accumulation of both tracers, but to different degrees. Dynamic SPECT showed increased or normal accumulation (i.e., essentially no discrepancy) in the first few minutes. However, Tc-99m HMPAO had a longer retention time than Tc-99m ECD in the ensuing 5-10 minutes. Dynamic SPECT revealed a similar accumulation pattern but different washout rates for the two tracers. Tc-99m HMPAO might be a more suitable tracer to detect high flow states or luxury perfusion because the findings on standard SPECT were more in agreement with those of dynamic SPECT using this tracer.

Technical points to improve surgical results in cases with basilar tip aneurysms.

Surgical results in 82 cases with aneurysm (61 ruptured and 21 unruptured) of the bifurcation of the basilar artery were analyzed and the causes of unfavorable outcome and its measures were discussed. Operation was performed in grade I, II, III, or IV of the Hunt and Kosnik's classification for the patients with ruptured aneurysm. Both in ruptured and unruptured cases, patient's age was not considered. As it turned out, 10 elderly (70 years old or older) cases (8 ruptured and 2 unruptured) were included in this study. Unilateral pterional approach was adopted for all but one case, and temporary clip and/or division of the hypoplastic posterior communicating artery was actively used. Surgery was completed with clipping of the aneurysm in all but six cases and overall surgical result consists of 70% of favorable outcomes. The main causes of unfavorable outcome were surgical procedures and primary brain damage due to subarachnoid hemorrhage. And the factors influenced to increase surgical technical damage to the brain were the patient's age, size of the aneurysm, and/or height of the neck from biclinoids line. The outcome of the higher grade (grade III or IV) in elderly cases was miserable, whereas it was not different from anterior circulation aneurysms in younger cases. From the result we concluded that the surgical indication for elderly cases should be limited in cases with lower grade (grade I or II) without large and/or high-positioned aneurysm. To obtain further improvement of the surgical result in younger cases, additional surgical techniques have to be considered to avoid the injury of perforating arteries from P1 and to reduce the pressure of the brain retraction which are the most important hazards for aneurysm surgery in this area.

Granulomatous angiitis of the central nervous system--case report.

A 22-year-old male presented with granulomatous angiitis manifesting as headache. Computed tomography (CT) demonstrated a low-density area and ring-like enhancement in the right frontoparietal region. Steroid therapy caused rapid improvement in the signs and symptoms. Withdrawal of steroid was followed by recurrence of the headache and low-density area. The steroid treatment was resumed until he became asymptomatic 3 months after admission. He was followed up as an outpatient once every 2 weeks. One month after discharge, he complained of mild headache, and CT again demonstrated a mild increase in the low-density area. He was followed up continuously without steroid treatment. Two months after discharge, he suddenly lost consciousness, and CT demonstrated multiple intracerebral hematomas in the bilateral parietal regions. Removal of an intracerebral hematoma in the right parietal region and external decompression were carried out, but he died 3 days later. Histological examination of tissues from the right parietal cortex and leptomeninges demonstrated granulomatous inflammation with several giant cells in the vessels of the cerebral cortex and leptomeninges.

Autoradiographic study of peripheral benzodiazepine receptors in animal brain tumor models and human gliomas.

In vitro binding of [3H]PK-11195 (1-(2-chlorophenyl)-N-methyl-(1- methylpropyl)-3-isoquinoline carboxamide) in rodent AA ascites and C6 glioma as well as in human gliomas was investigated. The Bmax (mean +/- S.D.) of AA ascites tumor and C6 glioma is 1.39 +/- 0.15 pmol/mg tissue and 4.50 +/- 0.76 pmol/mg tissue, respectively. This Bmax is 9 and 30 times, respectively, higher than the one found in the rat cortex (0.15 +/- 0.03 pmol/mg tissue). A Bmax of 1.26 +/- 0.24 pmol/mg tissue and 0.64 +/- 0.08 pmol/mg tissue was found in human malignant and low grade gliomas respectively. This Bmax value should be compared to 0.35 +/- 0.04 pmol/mg tissue found in the normal human cortex. There are significant (P less than 0.05) differences between Bmax in tumors and normal cortex. There was no significant difference in KD between the malignant and low grade gliomas. C6 glioma has a KD significantly greater than rat cortex. In some cases of human low grade gliomas, kinetic measurements suggested the presence of two affinity receptor sites. However, at this time, heterogeneity of the tissue cannot be excluded as being at least in part a source of this.

Influence of the tumor mass on the valine rate constants and on valine incorporation into proteins in an experimental brain tumor model.

Quantitative autoradiography was used to estimate regional transfer coefficients for valine incorporation and the rate of valine (exogenous and total) incorporation into proteins in an implanted brain-tumor model (AA ascites tumor). Special attention was paid to the evaluation of the tumor mass influence on the transfer coefficients and the rate of incorporation. The size of the tumors used in this study ranged from 2 to 5 mm in diameter. Nine groups of two to three animals each were used to determine the transfer coefficient. The transfer coefficients for movement of the label between different compartments were significantly greater in the tumor than in the normal brain. There is no tumor mass effect on the transfer coefficients or the rate of valine incorporation into proteins in surrounding or remote brain structures. The ratio between specific radioactivities of the free value in tissue and plasma was also measured. Results indicate that approximately the same fraction of the total valine is recycled in cortex as in the tumor tissue. The mean rates of exogenous valine incorporation into proteins (nmol g-1 min-1) is about one order of magnitude greater in the tumor than in the contralateral parietal cortex.

Partial resection of the gyrus rectus in pterional approach to anterior communicating artery aneurysms.

The effect of partial resection of the gyrus rectus during the unilateral pterional approach on surgical outcome was evaluated in 194 consecutive patients with ruptured anterior communicating artery aneurysms. Resection was performed more frequently in cases with poor clinical grade, in the acute stage, with superiorly directed aneurysms, and with high-positioned aneurysms. The surgical results were graded into three stages, and the follow-up results into five stages using the Glasgow Outcome Scale. Outcomes for 52 patients receiving gyrus rectus resection were compared with those for 142 patients without resection. There were no apparent effects caused by gyrus rectus resection on outcome.

Neurotoxicity after intracarotid 1,3-bis(2-chloroethyl)-1-nitrosourea administration in the rat: hemodynamic changes studied by double-tracer autoradiography.

Changes in blood-brain (BBB) permeability and local cerebral blood flow after intracarotid administration of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) were examined quantitatively in rats with double-tracer autoradiography using [14C]alpha-amino-isobutyric acid and [18F]fluoroantipyrine. Forty-eight female Wistar rats were divided into four groups. The control group (Group 1) received 1 ml of 5% dextrose. The other three groups received three different doses of BCNU dissolved in 5% dextrose: Group II rats received 1 mg, Group III 3 mg, and Group IV 10 mg. The tracer study was performed on Day 1 or Days 4 to 12 after intracarotid administration of BCNU. In 11 rats in Group II, there were no changes of BBB permeability. Transient BBB permeability changes were seen in the striatum or hippocampus in 3 of the 5 rats (60%) in Group III within 24 hours. In 8 of 9 rats (89%) in the same group, late BBB permeability changes were observed in the hypothalamus with or without histological changes. BBB permeability changes were seen in all rats of Group IV. Focal increase of local cerebral blood flow on the infused side compared with the non-infused side of the brain was observed, although not at a significant level, in 5 of 25 rats examined with [18F]fluoroantipyrine. The results of BBB permeability and histological examinations and study of heterogenous distribution by [18F]fluorodeoxyglucose indicated that the ipsilateral subcortical structures such as the hypothalamus, amygdala, internal capsule, and caudate putamen have the highest incidence of neurotoxicity, which are closely related to histopathological damage seen in human BCNU leucoencephalopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term observations in cases with spontaneous carotid-cavernous fistulas.

Twenty-six cases with spontaneous carotid-cavernous fistulas were followed up for periods ranging between 4 months and 9 years 8 months. A complete regression of symptoms without reappearance for more than 6 months was noted in 19 cases, a marked improvement in 2 cases, and a moderate regression in 3 cases. In 2 cases, symptoms have continued for 9 years 8 months and for 1 year. The regression of symptoms was usually delayed in patients less than 60 years old, in cases in which the symptoms developed slowly, and in cases with multiple draining veins. According to our observations a regression of symptoms may occur after very slight changes of haemodynamics. Compression of the cervical carotid artery for a short time or a temporary occlusion of the carotid artery by a balloon catheter should be considered as the treatment of choice in the first instance in cases with spontaneous carotid-cavernous fistulas showing relatively low pressure and low flow shunt.

Long-term observations in cases with spontaneous carotid-cavernous fistulas.

Twenty cases with spontaneous carotid-cavernous fistulas were followed up for periods ranging between 9 months and 9 years 8 months. In five cases, a temporary reappearance of symptoms was noted within 6 months after their regression. A complete regression of symptoms without reappearance for more than 6 months (between 6 months and 6 years 10 months) was noted in 18 cases, and a marked improvement was noted in one case. The regression of symptoms was usually delayed in patients less than 60 years old, in cases in which the symptoms developed slowly, and cases with three draining veins. According to these observations, noninvasive treatment is basically recommended in cases with spontaneous carotid-cavernous fistulas.