Under pressure: Syringo-subarachnoid shunting and syrinx cyst videoscopy

Background: Syringomyelia is a well-known spinal cord pathology characterized by an intramedullary cyst that is often chronic and can be progressive. The earliest techniques of syrinx decompression began with simple aspiration after laminectomy and predated anatomic imaging. This was followed by early attempts at keeping communication open between the syrinx and the subarachnoid space using various materials as conduits, essentially creating the first attempts at syringo-subarachnoid shunting (SSS). Even in the modern era of high-quality anatomic imaging with MRI and use of modern materials as implants, novel ways to maintain communication between a syrinx cavity and the subarachnoid space continue to be reported. Methods: A total of 212 patients with imaging-proven syringomyelia presented to our center between 2014 and 2019 and were retrospectively reviewed. The majority of these patients (197) had an identifiable primary cause and surgical treatment was directed at the underlying condition. A total of 18 patients had a T-tube style SSS placed at our center using a K-tube shunt. The mean follow-up was 31.5 months, mean age was 38 years (2–59). The European Myelopathy Score (EMS) and Chicago Chiari Outcome Scale (CCOS) were used to categorize outcomes and progress in these 18 patients. Also we report clinical case to demonstrate technique of K-tube use for syringo-subarachnoid shunting and potential abilities of inner syrinx cyst videoscopy for treatment of syringomyelia in 2-year-old patient with multiple congenital vertebral and spinal cord abnormality. Results: Among 16 patients available for follow-up 4 patients (25%) had neurological improvement, 12 patients (75%) remained clinically stable, and no patient had a neurological deterioration based on EMS. Using the CCOS 8 patients (50%) improved, 7 patients (44%) remained stable, and 1 patient (6%) worsened during in the follow-up period. Complications occurred in six patients (33%). Two patients had gait ataxia. Two patients developed postoperative meningitis treated successfully with antibiotics leaving the shunt in place. One patient had a CSF leak successfully treated with a lumbar drain. One patient developed a new pain syndrome. There was no mortality, shunt migration/malposition or reoperation. Conclusions: Syringo-subarachnoid shunting is a well-known and well-described procedure used as “second-line” treatment of syringomyelia worldwide. Our results are consistent with others and make this another surgical option if treatment of a primary source fails or no primary source of the syrinx is found. Our series of 18 patients using a T-tube style SSS adds another good option to those already in use. Recurrence or deterioration following syringomyelia shunting remains a problem and further refinement of technique remains an ongoing process. Syrinx inner videoscopy seems to be safe procedure with possible application to simplify the anatomy of cyst and liquid flow relief.