The Sir Alan Parks Physiology Unit, St Mark's Hospital and Academic Institute, Middlesex, UK.
Colorectal Dis. 2013 Sep;15(9):1140-4. doi: 10.1111/codi.12277.
Chronic idiopathic anal pain is a common condition of unknown aetiology. Patients may have co-existing psychiatric disorders and existing treatments are often ineffective. A small number of published case reports suggest that sacral nerve stimulation (SNS) could treat this condition. This pilot study aimed to investigate the efficacy of SNS for the treatment of chronic anal pain.
Ten patients with chronic idiopathic anal pain were recruited. All had failed to respond to conservative treatments. Clinical and psychological evaluation was performed in all patients prior to SNS. Temporary stimulation of the S3 foramina was performed for 3 weeks and outcome assessed by comparison of a pain score diary and visual analogue score obtained during stimulation and at baseline. Primary outcome was defined as a > 50% reduction in pain score.
Of the 10 patients recruited, five were found to have clinical depression. Four patients withdrew from the study prior to testing and six underwent peripheral nerve evaluation (PNE). Three patients had > 50% reduction in pain score and progressed to permanent SNS. Of these, only one had good pain control at latest follow-up of 5 years; the remaining two patients obtained no benefit and had their devices removed or deactivated. These two patients both had depression that was also not improved by SNS.
This study would suggest that SNS is not an effective treatment for chronic anal pain in the majority of patients. PNE is not an effective means of identifying which of these patients are likely to respond to permanent SNS.
慢性特发性肛门疼痛是一种病因不明的常见病症。患者可能同时存在精神疾病，且现有治疗方法往往无效。少数已发表的病例报告表明，骶神经刺激（SNS）可能对此种病症有效。本初步研究旨在探讨 SNS 治疗慢性肛门疼痛的疗效。
共招募了 10 名患有慢性特发性肛门疼痛的患者。所有患者均对保守治疗无反应。所有患者在接受 SNS 治疗前均进行了临床和心理评估。对 S3 神经孔进行了 3 周的临时刺激，并通过对比刺激期间和基线时的疼痛评分日记和视觉模拟评分来评估结果。主要结局定义为疼痛评分降低>50%。
在招募的 10 名患者中，有 5 名患者被发现患有临床抑郁症。4 名患者在测试前退出了研究，6 名患者接受了周围神经评估（PNE）。3 名患者的疼痛评分降低>50%，并进展为永久性 SNS。其中，只有 1 名患者在 5 年的最新随访中获得了良好的疼痛控制；其余 2 名患者没有获益，他们的设备被移除或停用。这两名患者的抑郁症也没有通过 SNS 得到改善。
本研究表明，SNS 不是大多数慢性肛门疼痛患者的有效治疗方法。PNE 并不能有效确定哪些患者可能对永久性 SNS 有反应。
