Postoperative Expansion of Dural Sac Cross-Sectional Area after Unilateral Laminotomy for Bilateral Decompression: Correlation with Clinical Symptoms

OBJECTIVE: Dural sac cross-sectional area (DSCSA) is a way to measure the degree of central spinal canal compression. The objective was to investigate the correlation between the expansion ratio of DSCSA after unilateral laminotomy for bilateral decompression (ULBD) and the clinical results for lumbar spinal stenosis. METHODS: We retrospectively reviewed the clinical data and radiographs of 103 patients who underwent ULBD for symptomatic spinal stenosis in one year. We compared preoperative and postoperative clinical data and DSCSA and evaluated the correlation between clinical and radiographic measurements. RESULTS: There was a significant increase of DSCSA after ULBD (p=0.000) and mean expansion ratio of DSCSA was 203.7+/-147.2%(range -32.9-826.1%). Clinical outcomes, measured by VAS and ODI were improved significantly not only in early postoperative period, but also in the last follow-up. However, there were no statistically significant correlations between the preoperative DSCSA and clinical symptoms, Perioperative expansion ratio of DSCSA and clinical parameters were also not correlated to the improvement of clinical symptoms significantly in both early postoperative phase and last follow-up. CONCLUSION: Our result indicates that the DSCSA itself has a definite limitation to be correlated to the clinical symptoms, and thus meticulous correlation between the clinical presentation and MRI imaging is essential in determination of surgical treatment.

A Case of The Surgically Treated Intraspinal Extradural Meningeal Cyst Demonstrating 'Ball-Valve' Mechanism of Formation

The intraspinal extradural meningeal cyst is a rare cause of compression of spinal cord. The most common clinical presentation is a slowly progressive myelopathy, but our case was presented with polyradiculopathy at admission. The authors believe that our case is particularly attributable to a ball-valve mechanism involving an idiopathic dural rent and a herniated segment of an underlying dorsal rootlet in the operative finding. As in our case, magnetic resonance imaging provides accurate diagnosis to identify an intraspinal extradural meningeal cyst. Closure of dural rent with marsupialization of the meningeal cyst through minimal laminectomy can be successfully managed with favorable clinical outcome as in our case.

Cellular Schwannoma of the Cervical Spine in an Infant: A Case Report

Cellular schwannoma is a very rare benign tumor involving peripheral nerves, mimicking malignant nerve sheath tumor in histological appearance. It is a clinico-pathological variant of benign schwannoma characterized by a high cellularity, increased mitotic figures and occasional presence of bone destruction. A 6-month-old female patient was admitted with progressive quadriparesis. Magnetic resonance imaging of the cervical spine showed a well-enhancing extramedullary mass on the C4 to C6 area. Total laminectomy was performed on C4-7, and intradural extramedullary tumor was removed. Histologically, the tumor was composed of proliferated spindle cells. Most of the tumor was composed of Antoni A area with hypercellular spindle cells arranged in fascicular pattern. The tumor cells showed mild atypism with mitotic figure upto 4/10HPF and diffuse, strong S-100 protein immunostaining. The patient was improved postoperatively.