Minor changes in regional cerebral blood flow revealed by the early distribution of I-123 IMP in brain.

To evaluate the early distribution of I-123 IMP in the brain, 10 dynamic images were obtained in the first 10 minutes after injection using a ring-type SPECT system with a high-sensitivity collimator. In cases of chronic carotid occlusion without brain CT abnormalities, areas of low perfusion were more clearly demonstrated in dynamic images than in static images obtained beginning 20 minutes after injection and continuing for 15 minutes using a high-resolution collimator. In cases of hyperperfusion following infarct or surgery, there was a difference between dynamic and static images in the visualization of hyperemic lesions. The distribution of I-123 IMP in the brain changes gradually, even in the early period after injection, and evaluation of early accumulation is useful for the detection of minor changes in regional cerebral blood flow.     

An unusual course of progressive multifocal leukoencephalopathy in a patient with idiopathic CD4+ T lymphocytopenia

A case is reported of idiopathic CD4+T lymphocytopenia withprogressive multifocal leukoencephalopathy and cervical lymph nodetuberculosis. A 57 year old Japanese man presented with cervical lymphadenopathy and progressive neurological deficits, and six monthslater he developed akinetic mutism. He had a persistent severelydepressed number of circulating CD4+T lymphocytes in the absence ofhuman immunodeficiency virus infection. T1 weighted MRI showed adiffuse decreased signal intensity limited to the white matter withoutmass effect. A brain biopsy specimen had a morphology similar to thatof progressive multifocal leukoencephalopathy. Polyomavirus antigen was detected in the brain lesion, and viral DNAwas identified in nucleated blood cells and urine. Unusually thisserious medical condition has lasted for more than three years withoutremission. To our knowledge this is the first patient withCD4+T lymphocytopenia with progressive multifocalleukoencephalopathy, suggesting that similar opportunistic infectionsshould be considered even in previously normal people.

     

Effects of calcium antagonists on the erythrocyte membrane.

The effects of dihydropyridine compounds nimodipine, nicardipine and NB818 (isopropyl methyl-6-carbamoyloxymethyl-4-(2,3-dichlorophenyl)-1,4-dihydro-2-methyl- 3,5- pyridine-dicarboxylate) on erythrocyte membranes have been studied. These compounds showed protective effects against hypotonic haemolysis, but not against heat-induced haemolysis. An increase in deformability of erythrocytes by these calcium antagonists was observed using a capillary tube centrifugal method. The erythrocytes showed slight stomatocytosis after 30 min of incubation with calcium antagonists, but did not show significant changes in mean corpuscular volume and ATP levels.     

Estimation of oxygen metabolism in a rat model of permanent ischemia using positron emission tomography with injectable15O-O2.

The threshold of cerebral blood flow (CBF) into infarction in rats has been indicated to be similar to that in patients. However, CBF does not reflect metabolic function, and so estimations of oxygen metabolism have been required. Here, we estimated changes in oxygen metabolism after occluding the right middle cerebral artery (MCA) in rats using an injectable (15)O-O(2) we developed. A decrease in CBF (left: 0.67+/-0.22 mL/min/g, right: 0.44+/-0.17 mL/min/g, P<0.05) and compensatory increase in the oxygen extraction fraction (OEF) (left: 0.42+/-0.13, right: 0.50+/-0.19, P<0.05) were observed at 1-h after occlusion. In contrast, a marked decrease in CBF and the cerebral metabolic rate for oxygen and a collapse of the compensatory OEF mechanism were found at 24 h after occlusion. Injectable (15)O-O(2) could be used to reliably estimate oxygen metabolism in an infarction rat model with positron emission tomography.     

Evaluation of probable or possible dementia with lewy bodies using 123I-IMP brain perfusion SPECT, 123I-MIBG, and 99mTc-MIBI myocardial SPECT.

We evaluated the diagnostic usefulness of combination studies with a statistical mapping method in N-isopropyl-p-(123)I-iodoamphetamine ((123)I-IMP) brain perfusion SPECT, cardiac sympathetic nerve function by (123)I-metaiodobenzylguanidine ((123)I-MIBG), and myocardial function by electrocardiographically gated (99m)Tc-sestamibi ((99m)Tc-MIBI) SPECT for patients with probable or possible dementia with Lewy bodies (DLB). METHODS: Twelve patients with probable DLB (7 male, 5 female; mean age +/- SD, 72.3 +/- 5.63 y; range, 65-82 y) and 9 patients with possible DLB (3 male, 6 female; mean age +/- SD, 73.1 +/- 9.23 y; range, 59-88 y) were enrolled in this study. (123)I-IMP SPECT images were analyzed with 3-dimensional stereotactic surface projections (3D-SSP) and the severity of ischemia was classified objectively using quantitatively analytic and display software; stereotactic extraction estimation (SEE) methods were compared with a normal database. In addition, we evaluated (123)I-MIBG heart-to-mediastinum (H/M) uptake ratios. Moreover, we performed (99m)Tc-MIBI SPECT to evaluate myocardial perfusion and the left ventricular ejection fraction (LVEF) compared with a normal database. RESULTS: 3D-SSP images of group comparison with healthy control subjects showed significantly decreased perfusion in the parietotemporal, occipital cortex, posterior cingulated, and precuneus regions in the probable DLB group but no significant reduction in the possible DLB group. Mean H/M ratios in the probable DLB group were significantly lower than those of the possible DLB group and the control group, respectively. Ten of 12 patients (83.3%) with probable DLB and 1 of 9 patients (11.1%) with possible DLB showed severe reduction in the bilateral occipital lobe and also a low (123)I-MIBG uptake. One patient (8.3%) with probable DLB and 2 patients (22.2%) with possible DLB showed no bilateral occipital hypoperfusion but showed low (123)I-MIBG uptake. One patient (8.3%) with probable DLB and 6 patients (66.7%) with possible DLB showed no occipital hypoperfusion and normal (123)I-MIBG uptake. (99m)Tc-MIBI gated SPECT did not indicate any wall motion abnormality in any subjects. CONCLUSION: These results suggest that combined examination of cerebral blood flow with 3D-SSP and SEE analysis, and cardiac sympathetic nerve function with (123)I-MIBG, would be a useful supporting diagnostic method in patients with DLB-particularly, in possible DLB and when cerebral blood flow does not indicate occipital hypoperfusion.     

Squamous cell carcinoma of the lung metastasized solitary cystic formation in the cerebellum

A 54-year-old male previously diagnosed as having a lung squamous cell carcinoma T2N2M0 in stage III A was readmitted to our hospital, as he was complaining of a gait disturbance. A brain CT, an MRCT scan, and vertebral arteriography revealed that the lung carcinoma had metastasized as a solitary cystic formation in the right cerebellum. Thus, a craniotomy, a cyst fluid aspiration, and tumoral resection was performed. Histopathological findings of the cyst wall indicated a squamous cell carcinoma, and the protogram of the cyst fluid found it similar to that of the serum. These findings suggest that destruction of the blood-brain-barrier by the invasion of the carcinoma caused an exudation of serum, resulting in the accumulation of cyst fluid.     

Floating knee fracture (ipsilateral fracture of the femur and tibia)--treatment by closed Ender nailing

Fourteen cases of ipsilateral fractures of the femur and tibia (floating knee fracture) were reviewed and patients were graded according to the type of fracture and the method of treatment. Using the criteria for assessment described by Karlstr?m and Olerud, patients were graded as excellent, good, fair and poor. Excellent results were achieved in five patients, good in three and fair in six. When the fracture extended into the knee, it caused knee problem in three out of five. In ten cases the femoral shaft fractures were nailed and in five both bones were nailed. Nailing of both femur and tibia gave good or excellent result in all five cases. As the comminution is often severe in the cases of floating knee fracture, intramedullary nailing by Küntscher may be difficult. We have introduced a closed Ender nailing for femoral and tibial shaft fractures and we have found that this method is also useful for the floating knee fracture. It is advantageous for this type of fracture, because it is technically simple, it has wide indications and it results in rapid bone union without knee disturbance.