Tadaki Kusunoki

Dynamics of cerebrospinal fluid circulation evaluated by metrizamide CT cisternography.

Cerebrospinal fluid (CSF) circulation has been analyzed by metrizamide computed tomography (CT) cisternography in 46 patients. Included were 7 patients without any clinical evidence of impaired CSF circulation, and 39 with hydrocephalus due to various causes. CT cisternography delineated the anatomical structures of the CSF pathways clearly and accurately and enabled us to analyze ventricular filling in a quantitative manner. As a result, a new, more precise CT cisternographic classification of the CSF flow patterns has been established. On the basis of the presence of ventricular reflux and stasis, extent of ventricular filling, and convexity flow of metrizamide, seven groups of flow patterns have been defined.

Comparison of Cerebrospinal Fluid Dynamics Studied by Computed Tomography (CT) and Radioisotope (RI) Cisternography

CT and RI cisternography were done on 55 cases with normal and abnormal CSF circulation. Of 19 cases in which both studies were done, 14 cases disclosed a good correspondence. The remaining five cases showed no correspondence because of technical failure. Analyzing the results, CT cisternography demonstrates pathology of the CSF dynamics in a more precise and quantitative manner than RI cisternography does. Metrizamide CT cisternography will soon be the most reliable method of investigation for the evaluation of the CSF kinetics.

Hydrodynamics in Normal Pressure Hydrocephalus — Correlation Between the Incidence of B-Waves, Dynamics of Cerebrospinal Fluid Circulation, and Cerebral Blood Flow

The purpose of this paper is to investigate the pathophysiology of the hydrodynamics in normal pressure hydrocephalus (NPH) and to suggest prognostic criteria by which patients with NPH who may benefit from a shunt can be selected.

CEREBRAL HEMODYNAMICS IN NORMAL-PRESSURE HYDROCEPHALUS: EVALUATION BY 133 Xe INHALATION METHOD AND DYNAMIC CT STUDY

Cerebral hemodynamics in 31 patients with suspected normal-pressure hydrocephalus were studied by means of the xenon-133 (133Xe) inhalation method and on dynamic computerized tomography (CT) scanning. Cerebral blood flow (CBF) is reduced in all patients with dementia. Hypoperfusion was noted in a frontal distribution in these patients compared with normal individuals. There was no difference in CBF patterns between patients with good and those with poor outcome. The CBF was increased following cerebrospinal fluid (CSF) shunting in patients who responded to that procedure: increase in flow correlated with clinical improvement, frontal and temporal lobe CBF was most markedly increased, and the CBF pattern became normal. In contrast, CBF was decreased after shunt placement in patients who were considered to have suffered from degenerative dementia, as evidenced by non-response to shunting. Dynamic computerized tomography studies demonstrated that patients with a good outcome showed a postoperative reduction in mean transit time of contrast material, most prominent in the frontal and temporal gray matter, and slight in the deep frontal structures, but not in the major cerebral vessels. Patients with poor outcome after shunting, however, had an increase in transit time in all regions. This corresponded well with the results as determined by the 133Xe inhalation method.