Intraoperative Ultrasound Imaging Features in High-grade Metastatic Spinal Cord Compression Treated with Separation Surgery

Researchers at the University of Texas MD Anderson Cancer Center have identified key intraoperative ultrasound (iUS) findings that correlate with adequate decompression and prognostication of functional status in patients undergoing separation surgery for high-grade malignant epidural spinal cord compression. The study, published in Neurosurgical Focus, analyzed 24 iUS images and videos obtained from 8 patients (age range 48-68 years) who underwent surgery. The researchers assessed various iUS parameters, including subarachnoid compartment distances, spinal cord deformation, and hyperechoic signal presence. The findings suggest that intraoperative US is a practical and effective tool for assessing the extent of separation achieved during surgery.

Key Takeaways:

• The minimum distance between the residual tumor and the spinal cord was 5 mm (mean 6.9, range 5-10 mm).
• The mean spinal cord sagittal deformation angle after decompression was 172 degrees.
• The mean widths of the dorsal and ventral subarachnoid compartments were 1.5 mm and 3.3 mm, respectively.
• The mean anteroposterior and transverse diameters of the spinal cord were 5.6 mm and 9.2 mm, respectively.
• All patients with hyperechoic punctate areas in the white matter of the spinal cord experienced new or persistent neurological deficits, which improved during hospitalization.
• The ultrasonographic features described in this study are easily reproducible and could be used to develop a standardized approach for evaluating spinal cord decompression in cases of separation surgery.
• Future longitudinal studies are needed to validate if intramedullary hyperechoic signal has prognostic value for neurological recovery and if the distance from the spinal cord to residual disease serves as a predictor of local control.

Statistics:

• 24 iUS images and videos were analyzed from 8 patients (age range 48-68 years) who underwent separation surgery.
• The minimum distance between the residual tumor and the spinal cord was 5 mm (mean 6.9, range 5-10 mm).
• The mean spinal cord sagittal deformation angle after decompression was 172 degrees.
• The mean widths of the dorsal and ventral subarachnoid compartments were 1.5 mm and 3.3 mm, respectively.
• The mean anteroposterior and transverse diameters of the spinal cord were 5.6 mm and 9.2 mm, respectively.

Sources:

• Intraoperative Ultrasound Imaging Features In High-grade Metastatic Spinal Cord Compression Treated With Separation Surgery. Neurosurgical Focus, 2024;58(5).
• Neurosurgical Focus. Amer Assoc Neurological Surgeons, 5550 Meadowbrook Drive, Rolling Meadows, IL 60008, USA.
• University of Texas MD Anderson Cancer Center. Department of Neurosurgery, Houston, TX, United States.