gms | German Medical Science

Objective: As intraspinal cavernomas are increasingly detected with modern imaging techniques surgical treatment can be an option to prevent deficits following hemorrhage or to reduce symptoms. Neuronavigation provides a helpful tool in intracranial procedures and spinal instrumentation but is of limited use for surgery inside the spinal cord. Especially in deeply located small cavernomas with no or only minor bleeding an exact localization can be difficult.

Methods: Modern ultrasound devices provide high resolution and small ultrasound probes that can be used for intraoperative intraspinal localization of small intramedullary lesions. The technique has been used in eight patients with small cavernomas beneath the surface with difficulty to localize the most direct and minimally invasive access.

Results: Preoperative symptoms of the patients varied from arm or leg pain to dysesthesia, numbness and spastic or atactic gait. The age of the patients was between 23 and 71 years (mean 44 years). Location of the cavernomas was the cervical (n=4) and the thoracic spine (n=4). The intraoperative ultrasound was used transdurally in all patients to confirm the extent of laminectomy, wich was enlarged in two cases. In three patients additionally an intradural localization with an echogenic marker was successfully applied leading to a direct access to the lesion. Postoperatively the symptoms of the patients improved in 5 patients, 2 patients remained unchanged, one patient suffers from persisting neuropathy. The follow-up MRI scans showed no recurrent cavernoma in any patient.

Conclusions: Intraoperative ultrasound is a reliable method for localization of deeply seated cavernous lesions inside the spinal cord without signs on the pial surface. Transdural imaging confirms the correct level, intradural sonography together with echogenic markers provides exact determination of the least harmful intramedullary access and helps to minimize postoperative deficits.