Dilated pericerebellar fluid space in patients with chronic subdural hematoma
Tsuiki, H.; Yoshida, S.; Matsumoto, S.; Shingu, T.; Sato, S.; Motozaki, T.; Ban, S.; Yamamoto, T.
No Shinkei Geka. Neurological Surgery 22(3): 231-233
1994
ISSN/ISBN: 0301-2603 PMID: 8133963 Document Number: 426230
It is not uncommon to observe the dilatation of the pericerebellar fluid space (PCFS) on CT in patients with chronic subdural hematoma (CSDH). CT scans of 92 patients with CSDH proven by surgery were reviewed with respect to the dilatation of PCFS and we evaluated the incidence of dilated PCFS and the relationship between PCFS and other factors. There were 68 males and 24 females. Patients ranged in age from 20 to 90 years (mean 65.2 years) . Another 50 patients without CSDH were also reviewed as a control group. A new PCFS grading based on the CT findings was proposed, divided into 3 grades as follows. In grade 0, no PCFS could be seen on CT scans. In grade 1, PCFS could be detected along the posterior aspect of the perrous pyramid, and in grade 2, PCFS could be seen not only along the posterior aspect of the petrous pyramid but also under the tentorium cerebelli. The dilatation of PCFS was seen in 78 patients (84.8%) out of the 92 cases. In 50 patients without CSDH (control group), the dilatation of PCFS was noted only in 6 (12%). The dilatation of PCFS was almost always seen on the same side as the CSDH. Among many factors, the significant factor was the degree of the midline shift, the bigger the midline shift caused by CSDH, the larger was the dilated PCFS. Although the mechanism of the dilated PCFS in patients with CSDH is not clear, it is postulated that the mechanism is caused by CSF flow disturbance, compression or adhesion of the subarachnoid space due to CSDH. It should be emphasized that recognition of the dilated PCFS is a clue to make early diagnosis of CSDH, and is useful for better understanding of the pathogenesis of CSDH and CSF circulation.