1. 2007;10;661-666Transsacrococcygeal Approach to Ganglion Impar Block for Management of Chronic Perineal Pain: A Prospective Observational Study
   Prospective Evaluation
   G.P. Dureja, MD, Gokul R. Toshniwal, MD, and S.M. Prashanth, MD.

Background: The ganglion impar or ganglion of Walther is a solitary retroperitoneal structure at the level of sacrococcygeal junction. It provides the nociceptive and sympathetic supply to the perineal structures. Chronic Perineal Pain (CPP) has been effectively managed by ganglion impar block. In this study we analyze the feasibility, safety, and efficacy of ganglion impar block by transsacrococcygeal approach.

Design: An observational report.

Methods:  In this prospective study, 16 consecutive patients who required ganglion impar block for CPP were followed for two months. After informed and written consent, the ganglion impar was blocked under aseptic precautions, using a transsacrococcygeal approach. The Visual Analogue Scale for pain (VAS) at presentation time required for the pain to reduce by 50% to be considered effective and VAS was recorded at different time points during 2-month follow-up, and time required to perform the procedure, number of attempts, and any complications were also noted.

Results: All the blocks were effective with a mean duration of 12±3 minutes for 50% reduction in VAS. The mean duration required to perform the procedure in neurolytic block patients was 7.8±2 minutes and 5.7±1minutes in therapeutic block patients. There were no adverse events. All the patients had significant pain relief during 2 month follow-up (P <0.05 compared to baseline). The mean VAS at 2 months was about 2. Statistical analysis was done by using paired “t”/Wilcoxon signed rank test.

Conclusion: A transsacrococcygeal approach for a ganglion impar block is a technically feasible and safe technique. We recommend this technique for neurolysis or radiofrequency ablation of the ganglion impar and for diagnostic blocks, especially when the diagnosis and further plan of management is dependent on the response of the diagnostic block.