経肛門的ヒルシュスプルング病根治術後の便失禁に対する肛門管形成手術 Anal Canal Plastic Surgery for Fecal Incontinence After Transanal Endorectal Pull-Through for Hirschsprung Disease

【目的】経肛門的ヒルシュスプルング病根治術後に溢流性以外の便失禁を認める症例に対し肛門管形成手術を行い，その排便機能における効果を検討した．<br>【方法】手術は大見らが報告した成人の内肛門括約筋後方形成手術に準じて行った．乳児期までに経肛門的Soave 法を行い，術後5 年以上経過して重度の溢流性以外の便失禁を認める症例を手術適応とした．術前後の排便機能を直腸肛門奇形研究会による臨床スコア（試案），注腸造影そして肛門内圧検査により評価した．<br>【結果】教室で経肛門的Soave 法施行後の31 例中7 例（22.5％）が対象となった．男児6 例，女児1 例で年齢は10.5±2.4 歳，3 例がlong segment aganglionosis，2 例がrectosigmoid aganglionosis，2 例がshort segment aganglionosis であった．排便スコアは，術前1.42±0.4（全例Poor）であったが，術後4.7±2.3（Good 2 例，Fair 4 例，Poor 1 例）と有意に上昇した（<i>p</i>＜0.05）．なかでも便意に異常がなかった症例では極めて良好な効果が得られた．術前に注腸造影を行った5 例で全例造影剤の直腸内保持が不可能であったが，術後いずれも造影剤の直腸内保持が可能となった．術前の肛門管最大静止圧は26.8±10.7 mmHg であったが，術直後は有意に上昇した（84.9±27.9 mmHg，<i>p</i>＜0.05）が，術後2 か月以後に再度測定した6 例では徐々に低下し，術前と有意差はなかった（37.3±14.6 mmHg，<i>p</i>＝0.08）．<br>【結論】経肛門的ヒルシュスプルング病術後の溢流性以外の便失禁に対し，本術式が有用であると考えられた．今後も長期的な排便機能のフォローアップを行う必要がある．

<i>Purpose</i>: We performed anal canal plastic surgery on patients with fecal incontinence other than overflow incontinence after a transanal endorectal Soave procedure and evaluated its efficacy in restoring anorectal function.<br><i>Methods</i>: The procedure was performed on adult patients and reported by Ohmi et al. We applied the technique to patients with severe fecal incontinence other than overflow incontinence more than 5 years after a Soave procedure and evaluated anorectal function using the Japanese Study Group of Anorectal Anomalies (SGAA) clinical assessment of defecation function score, contrast enema, and anorectal manometry.<br><i>Results</i>: Seven (22.5%) of 31 patients (6 males, 1 female) were indicated for the procedure. The patients included three with long-segment aganglionosis, two with rectosigmoid aganglionosis, and two with short-segment aganglionosis. The mean preoperative SGAA score was 1.42 ± 0.4. Postoperatively, the mean SGAA score significantly improved to 4.7 ± 2.3 (<i>p</i> < 0.05). In particular, patients with normal anorectal sensation showed marked improvement. Five patients who were unable to retain the contrast material in their rectum preoperatively were able to do so after the operation. The mean maximum rest pressure of the anal canal preoperatively was 26.8 ± 10.7 mmHg. Postoperatively, this increased significantly to 84.9 ± 27.9 mmHg (<i>p</i> < 0.05). However, by 2 months after the operation, it decreased close to preoperative levels (37.3 ± 14.6 mmHg) or showed no significant difference from preoperative levels (<i>p</i> = 0.08).<br><i>Conclusions</i>: This procedure is an effective treatment for fecal incontinence other than overflow incontinence after a transanal endorectal Soave procedure. Evaluation of long-term outcomes is required.