Clinical factors for the development of posttraumatic hydrocephalus after decompressive craniectomy.

OBJECTIVE: Earlier reports have revealed that the incidence of posttraumatic hydrocephalus (PTH) is higher among patients who underwent decompressive craniectomy (DC). The aim of this study was to determine the influencing factors for the development of PTH after DC. METHODS: A total of 693 head trauma patients admitted in our hospital between March 2004 and May 2007 were reviewed. Among thee, we analyzed 55 patients with severe traumatic brain injury who underwent DC. We excluded patients who had confounding variables. The 33 patients were finally enrolled in the study and data were collected retrospectively for these patients. The patients were divided into two groups: non-hydrocephalus group (Group I) and hydrocephalus group (Group II). Related factors assessed were individual Glasgow Coma Score (GCS), age, sex, radiological findings, type of operation, re-operation and outcome. RESULTS: Of the 693 patients with head trauma, 28 (4.0%) developed PTH. Fifty-five patients underwent DC and 13 (23.6%) developed PTH. Eleven of the 33 study patients (30.3%) who had no confounding factors were diagnosed with PTH. Significant differences in the type of craniectomy and re-operation were found between Group I and II. CONCLUSION: It is suggested that the size of DC and repeated operation may promote posttraumatic hydrocephalus in severe head trauma patients who underwent DC.

Morphological study of sinus flow in the confluence of sinuses.

The confluence of sinuses (CS; torcular herophili) is represented by the junction of the superior sagittal (SSS), straight (SS), occipital (OS), and two transverse sinuses (TS). The objective of this study was to interpret sinus flow around the CS by morphological investigation of the sinuses. This study is based on visual examination of dural venous sinuses in the region of the CS in 31 adult cadavers. In the inflow zone, we examined the direction of SSS and SS flow. In the communication zone, we examined the extent to which outflow sinuses communicate with other sinuses. In the outflow zone, we used the diameters of outflow sinuses to determine anatomical dominance. The SSS entered the CS via the right TS in 16 cases (51.6%) and via the center of the CS in 14 cases (45.2%). The SS entered via the center of the CS in 18 cases (58.1%) and via the left TS in 11 cases (35.5%). Outflow sinuses communicated freely in 26 cases (83.8%) and communicated partially in five cases (16.2%). Partial communication was the result of a septate CS. In terms of outflow, the right TS was dominant in 11 cases (35.5%), and in 18 cases (58.1%), outflow was symmetrical. The direction of SSS inflow was different from that of SS inflow, and partial communication was observed in five cases (16.1%). Therefore, the presence of a septum may be considered an anatomical factor, with implications in diagnosis or in the sacrifice of the outflow sinus of the CS.

Neurenteric cyst in the cerebellopontine angle with xanthogranulomatous changes: serial MR findings with pathologic correlation.

We report serial MR findings in a middle-aged woman with a neurenteric cyst involving the cerebellopontine angle cistern with xanthogranulomatous changes. On the initial gadolinium-enhanced T1-weighted MR images, the solid portion of the lesion had homogeneously strong enhancement. Follow-up MR images obtained 6 months later showed that the mass had increased in size; however, the solid portion decreased in size. The enhancing solid portion corresponded to the xanthogranulomatous changes on pathologic correlation.

Spontaneous partial regression of cerebral arteriovenous malformation.

Arteriovenous malformation (AVM) of the brain is one of the important pathologic conditions which cause intracerebral or subarachnoid hemorrhage, epilepsy, or chronic cerebral ischemia. The spontaneous regression of cerebral AVM is reported to be very rare and more likely to occur when the AVM is small, is accompanied by hemorrhage, and has fewer arterial feeders. We report a case of right occipital AVM which at follow-up angiography performed four years later showed near-complete spontaneous regression.