Introduction: This study retrospectively reviewed the value of alcohol injection of sacral nerve roots after a lidocaine test in two indications: detrusor instability-detrusor hyperactivity syndrome and cystalgia.
Material and methods: Single-centre retrospective study from January 1992 to March 2003. Twenty-eight patients (1 man, 27 women) were admitted to the urology department for lidocaine test injection because of detrusor hyperactivity 24 cases (idiopathic = 13, neurological = 11), and cystalgia in another 4 cases.
Results: After the lidocaine test, infiltration of the sacral nerve roots (bilateral S3) by 70% alcohol was performed in 24/28 cases. The therapeutic effect was assessed at 1 month: 14 out of 24 patients reported that they were globally improved by the alcohol injection. The mean duration of the therapeutic effect was 3.8 months. In the longer term, only one of the 14 patients initially improved did not subsequently experience deterioration of the clinical features (with a follow-up of 8 months). A second alcohol injection was performed in 5/28 patients, with a positive result in only one case (4%).
Complications: 6/24 (25%) patients developed lower limb pain that resolved over 2 to 3 months; 3/24 (12%) presented immediate postoperative urinary retention (that persisted in the long term in 1 case); 1/24 (4%) presented cicatricial anal incontinence.
Conclusion: Alcohol injection of sacral nerve roots is a simple and inexpensive technique, but is associated with morbidity, and has inconstant and only transient effects. It can only be considered exceptionally in highly selected cases when no more effective treatments are available, such as botulinum toxin injection or sacral nerve root neuromodulation.