CT-guided indirect percutaneous facet synovial cyst rupture combined with direct fenestration: 10-year review at a single institution.

Background: Facet synovial cysts (FSCs) are benign, extradural outpouchings arising from the facet joint that can cause radiculopathy. Effectiveness of CT-guided indirect percutaneous cyst rupture (IPCR) alone and direct fenestration (DF) treatment alone have previously been reported in large cohorts. We performed a retrospective review of all FSCs treated under CT-guidance at a single institution where patients underwent IPCR, and IPCR followed by DF if necessary. We hypothesized that CT-guided FSC rupture would demonstrate similar effectiveness to previously reported fluoroscopic-guided methods, with potential improvement due to the opportunity to employ the DF technique in cases of IPCR failure. Methods: A search was conducted of all CT-guided FSC rupture procedures over 10 years. Data included demographics, needle gauge used for IPCR and DF, rupture success, cyst size and T2 intensity, presence of spinal hardware, and cyst location. Subsequent surgery at the level of the cyst was documented. Results: 90 FSC rupture attempts were performed on 75 patients (28 M/47 F). FSC rupture using IPCR had a 70.0% success rate. In 22 FSC rupture attempts, IPCR failed and was followed by DF, with a success rate of combined IPCR + DF of 90.6 %. Subsequent surgery was required for 36.0% of patients involving the same level as the cyst or cysts. Conclusion: Rates of successful FSC rupture under CT-guidance increased when the indirect rupture technique could be followed by direct fenestration in cases of failure. Our findings emphasize the benefits of flexibility afforded to the operator with CT-guidance.