Cerebral Hemodynamic Analysis in Pediatric Moyamoya Patients using Perfusion Weighted MRI

OBJECTIVE: Classically, single photon emission tomography is known to be the reference standard for evaluating the hemodynamic status of patients with moyamoya disease. Recently, T2-weighted perfusion magnetic resonance(MR) imaging has been found to be effective in estimating cerebral hemodynamics in moyamoya disease. We aim to assess the utility of perfusion-weighted MR imaging for evaluating hemodynamic status of moyamoya disease. METHODS: The subjects were fourteen moyamoya patients(mean age: 7.21yrs) who were admitted at our hospital between Sep. 2001 to Sep 2003. Four normal children were used for control group. Perfusion MR imaging was performed before any treatment by using a T2-weighted contrast material-enhanced technique. Relative cerebral blood volume(rCBV) and time to peak enhancement(TTP) maps were calculated. Relative ratios of rCBV and TTP in the anterior cerebral artery(ACA), middle cerebral artery(MCA) and basal ganglia were measured and compared with those of the posterior cerebral artery(PCA) in each cerebral hemispheres. Using this data, we analysed the hemodynamic aspect of pediatric moyamoya disease patients in regarding to the age, Suzuki stage, signal change in FLAIR MR imaging, and hemispheres inducing symptoms. RESULTS: The mean rCBV ratio of ACA, MCA did not differ between normal children and moyamoya patients. However the significant TTP delay was observed at ACA, MCA territories (mean = 2.3071 sec, 1.2089 sec, respectively, p < 0.0001). As the Suzuki stage of patients is advanced, rCBV ratio is decreased and TTP differences increased. CONCLUSION: Perfusion MR can be applied for evaluating preoperative cerebral hemodynamic status of moyamoya patients. Furthermore, perfusion MR imaging can be used for determine which hemisphere should be treated, first.

Primary Central Nervous System Lymphoma(PCNSL): Treatment Result of 23 Cases

The authors report below a clinical study of 23 patients bearing 31 primary central nervous system lymphomas diagnosed between January 1985 and December 1994. The cohort included 13 men and 10 women whose mean age was 46 years, ranging from 28 to 61 years. No patient had antecedent of human immunodeficiency virus positivity but one had a past history of rheumatoid arthritis. The duration of symptom was less than 8 weeks in 52% of the patients. Symptom groups included increased intracranial pressure(78%), focal neurological decificit(52%), neuropsychiatric symptoms(43%), and seizures(13%). The histopathologcal diagnosies were done in 19 cases(10 cases by resective surgery, 9 cases by open or stereotactic biopsy). The others were diagnosed by the typical clinical course such as rapid disappearance of lesions after steroid therapy, and/or radiological findings. Histological subtypes(National Cancer Institute Working Formulation) was confirmed in 8 patients including 3 cases of diffuse larger cell type. Phenotype was determined in 7 patients: 4 were B-cell type and 3 were T-cell type. One patient committed suicide during the radiation therapy and was therefore excluded from the survival analysis. All but two patients received radiation therapy. Five patients received chemotherapy. The over-all Kaplan-Meier survival rate was 46% at 2 years and 15.5% at 5 years. On univariate analysis, statistically significant prognostic factor associated with survival was not found but the higher Karnofsky score and single lesion were found to be favorable to the long-term survival. In the statistical analysis of the patients who received radiation therapy, surgical resection did not significantly influence the survival.

The Effect of Naloxone for the C.N.S. Lesion

Naloxone, specific opiate antagonist, selectively elevates plasma dopamine level, with the dopamine changes significantly correlated with improved cardiovascular function and reduces the release of endorphin in the endorphin stress system. As the results, naloxone increases both, systemic blood pressure and regional blood flow, limiting secondary ischemic changes and improving neurological function in the C.N.S. lesion by the experimental studies. We have studied the clinical effects of naloxone on the 40 cases of C.N.S. lesions from April to October, 1983. We have discussed our results and reviewed literatures.