CT-guided Intramuscular Injection of Botulinum Toxin a for Treatment of Myofascial Pelvic Pain: Single Center Evaluation of Safety and Early Efficacy

Monday, Nov. 28 3:10PM - 3:20PM Room: N226

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Anna Moreland, MD, Baltimore, MD (Presenter) Consultant, NeuWave Medical, Inc
Greg Minwell, MD, Baltimore, MD (Abstract Co-Author) Nothing to Disclose
Alexander J. Kieger, MD, Baltimore, MD (Abstract Co-Author) Nothing to Disclose
Douglas B. Yim, MD, San Diego, CA (Abstract Co-Author) Nothing to Disclose
Kelvin K. Hong, MD, Baltimore, MD (Abstract Co-Author) Scientific Advisory Board, Boston Scientific Corporation

Myofascial pelvic pain and spasm are a significant source of morbidity among affected patients, and may be treated with botulinum toxin A (Botox) injection into pelvic floor muscles. Conventional injections are performed by a gynecologist using physical exam landmarks without imaging guidance. CT-guidance of injections may offer benefits due to ability for definitive localization of injections to target. The present study aims to evaluate the safety and efficacy of CT-guided intramuscular injection of Botox for treatment of myofascial pelvic pain.


Between 07/2013 and 03/2016, n = 57 patients with myofascial pelvic pain and spasm were treated with CT-guided pelvic floor muscle Botox injections in 76 treatment sessions.  Referrals were made by gynecologists specializing in chronic pelvic pain, who requested injection of specific pelvic floor muscles in each patient according to point tenderness on pelvic exam. Following scout CT, A 22 gauge needle was placed into each target muscle under CT fluoroscopic guidance. Botox suspended in saline was injected into the piriformis, obturator internus, and/or levator ani (n = 53, 6, and 12 treatments, respectively). Visual analog scale pain scores (on a 10-point scale) were compared immediately pre- and post-procedure, and at follow-up clinic appointments.


Successful injection of the full dose of Botox to the target muscle was accomplished in all cases, conferring a technical success rate of 100%. There were no major or minor complications by SIR criteria as assessed immediately post procedure or at follow up clinic appointments, including no patient report of urinary or fecal incontinence in any case. Lower visual analog pain scores were reported post procedure following 68% of treatments, with the difference in scores demonstrating statistical significance (p = 0.03).


CT-guided Botox injection of pelvic floor muscles is a technically feasible, safe, and frequently efficacious option for treatment of myofascial pelvic pain. Further evaluation of the durability of response, predictors of efficacy to guide patient selection, and comparison to conventional injections without CT guidance may be warranted.


CT-guided percutaneous injection of Botox into pelvic floor muscles for treatment of myofascial pelvic pain demonstrates similar efficacy and lower complication rates as compared to those published for non-CT-guided injections.