Can cerebrovascular reactivity be assessed by dynamic susceptibility contrast-enhanced MRI?Berthezene, Y.; Nighoghossian, N.; Meyer, R.; Damien, J.; Cinotti, L.; Adeleine, P.; Trouillas, P.; Froment, J. C.
doi: 10.1007/s002340050527pmid: 9493178
The acetazolamide (ACZ) test is performed to evaluate the decrease in cerebral perfusion pressure (CPP) by investigation of vasomotor reactivity (VMR). Our aim was to study cerebral blood flow and blood volume changes induced by the ACZ test in healthy control subjects using dynamic susceptibility contrast-enhanced gradient-echo MRI (DSC-MRI). A FLASH sequence was used to produce susceptibility-weighted images during an intravenous injection of 0.1 mmol/kg gadopentetate dimeglumine (Gd-DTPA). After the first dynamic study, 1 g acetazolamide was given intravenously and 10 min later a second bolus of Gd-DTPA was injected. Using the indicator-dilution theory, relative cerebral blood volume and relative cerebral blood flow were estimated. In healthy subjects the ACZ test induced a significant increase in relative blood volume (from 80.5 ± 10.7 to 113.4 ± 11.9) and relative blood flow (from 5.73 ± 0.96 to 7.5 ± 0.97), symmetrically in the cerebral hemispheres. This approach might be promising in the understanding of cerebral haemodynamics in patients with vascular disorders.
The need for repeat angiography in subarachnoid haemorrhageUrbach, H.; Zentner, J.; Solymosi, L.
doi: 10.1007/s002340050528pmid: 9493179
This study was designed to assess the necessity for a second angiogram study in patients in whom initial angiography after primary subarachnoid haemorrhage (SAH) was negative. During a 12-year period, 122 of 694 patients (17.5 %) had negative initial angiograms. CT, available for 98 patients, showed a preponderance of subarachnoid blood in the perimesencephalic cisterns in 50 of 73 patients (68.5 %) in whom blood was visible on CT. Angiography, repeated in 67 patients, revealed an aneurysm in 4 (6 %): 2 had an aneurysm of the anterior communicating artery, 1 of the posterior inferior cerebellar artery, and 1 of the P2 segment of the posterior cerebral artery. CT showed subarachnoid blood in the interpeduncular and ambient cisterns in this last case, and a preponderance of subarachnoid blood outside the perimesencephalic cisterns in the remaining 3 patients.
Stroke due to a fusiform aneurysm of the cervical vertebral artery: case reportSuzuki, S.; Inoue, T.; Haga, S.; Nishio, S.; Kono, S.; Mizushima, A.; Fukui, M.
doi: 10.1007/s002340050531pmid: 9493182
Aneurysms of the cervical vertebral artery (VA) are uncommon; they are often caused by trauma or spontaneous dissection. A fusiform aneurysm without evidence of atherosclerosis or dissection has not been reported previously. A 46-year-old man presented with a pontine infarct. Imaging revealed a fusiform aneurysm of the left VA at the C5–6 level, with occlusion of the basilar artery. Associated minor anomalies included fusion of the vertebral bodies of C5 and C6, cervical rib and platybasia. The left VA arose directly from the aortic arch and entered the transverse foramen at the C4 level. Hyperextension and left lateral flexion of the neck caused kinking of the VA proximal to the aneurysm. Turbulent flow in the aneurysm lumen was noted on angiography.
High-dose gadolinium-enhanced MRI for diagnosis of meningeal metastasesKallmes, D. F.; Gray, Linda; Glass, J. P.
doi: 10.1007/s002340050532pmid: 9493183
We compared high-dose (0.3 mmol/kg) and standard-dose (0.1 mmol/kg) gadolinium-enhanced MRI for diagnosis of meningeal metastases in 12 patients with suspected meningeal metastases. They were imaged with both standard-dose and high-dose gadolinium. All patients with abnormal meningeal enhancement underwent at least one lumbar puncture for cerebrospinal fluid (CSF) cytology, while patients with normal meningeal enhancement were followed clinically. All patients with negative CSF cytology also were followed clinically. A single observer reviewed all the images, with specific attention to the enhancement pattern of the meninges. Abnormal leptomeningeal enhancement was present in three cases, and abnormal pachymeningeal enhancement in three other patients. All of these patients had abnormal CSF analyses. In two of the three cases of abnormal leptomeningeal enhancement the disease was more evident on high-dose than on standard-dose imaging; in one case the abnormal enhancement was visible only on high-dose imaging. In one of the three cases with abnormal pachymeningeal enhancement, the disease was evident prospectively only with high-dose imaging.
Dilated Virchow-Robin spaces: MRI pathological studyAdachi, M.; Hosoya, T.; Haku, T.; Yamaguchi, K.
doi: 10.1007/s002340050533pmid: 9493184
We performed a histopathological study of two human brains to look at dilated Virchow-Robin (V-R) spaces in the anterior perforated substance and putamen. We measured the diameter of 74 arteries in 54 dilated V-R spaces. In 28 patients without neurological deficits we ascertained the characteristic location of dilated V-R spaces in the anterior perforated substance and basal ganglia on MRI, measuring the distance from 64 foci of cerebrospinal fluid signal intensity to the centre of the mamillary body on 1 mm thick images. In the histopathological study, the mean diameter of the arteries was 39.0 ± 36.0 μm. Dilatation of the V-R space was observed from the end of the indentation of the pial membrane towards the brain surface along the perforating artery. In the MR images, the mean distance from the dilated V-R space to the mamillary body was 10.0 ± 4.5 mm. The V-R space was confined to a fixed level in the lower part of the basal ganglia, and not found near the brain surface.
Differences on intraoperative ultrasonography between meningioma and neurilemmomaMatsuzaki, H.; Tokuhashi, Y.; Wakabayashi, K.; Ishihara, K.; Iwahashi, M.
doi: 10.1007/s002340050536pmid: 9493187
We examined the differences on intraoperative ultrasonography between 17 cases of meningioma and 29 of neurilemmoma, the common intradural extramedullary tumors. In meningiomas, cysts were rarely seen (in 12.5 %, P < 0.01 %) and echogenicity was high (in 82.3 %, P < 0.01 %). In neurilemmoma, many cysts were seen (72.5 %) and low echoes tended to be more common (72.4 %, P < 0.01 %). In the neurilemmomas with high or isoechogenicity, Antoni A types, histologically rich in collagen fibres, predominanted.