Anatomical characteristics of anal fistula evaluated by three-dimensional anorectal ultrasonography: is there a correlation with Goodsall's theory?

Abstract

Purpose We aimed to correlate the course of the anal fistula tract (T), location of the external opening (EO) and internal opening (IO) in anterior (A) and posterior (P) circumference using 3D-US according to Goodsall's rule.

Methods 151 patients with primary cryptoglandular Transsphincteric fistulas were examined with 3D-US and compared with surgical finding. The type of the T (straight or curved), EO and IO were identified and divided into 3 Groups: GI: EO and IO are located in a position; GII: EO and IO are located in P position and GIII: OE and OI are located in the opposite position. The findings were correlated with Goodsall's rule.

Results 74/151(49%) were included in GI, of them, 41 (55%) were male (33/44% had straight tract and 8/11% curved) and 33 (45%) female (15/20%-straight and 18/25%-curved). GII included 68 (45%), of them, 50 (74%) were male (39/57%-straight and 11/15%-curved) and 18 (26%) female (14/20%-straight and 04/8%-curved). GIII = 9 (6%) and all of them had curved tract. The overall concordance between 3D-US and surgical finding was 98% for tract and 96% for IO.

Conclusion The 3D-US findings correlate with the Goodsall's rule in transsphincteric fistulas located in the anterior circumference straight type, in male, while in females the distribution of curved and straight paths is similar. In the posterior circumference no correlation was observed in both the sexes.

Resumo

Objetivo Correlacionar o trajeto (T) da fístula anal, localização do orifício externo (OE) e orifício interno (OI) na hemicircunferência anterior (HCA) e posterior (HCP), utilizando 3D-US, com a lei de Goodsall.

Método 151 pacientes com fístulas transesfinctéricas criptoglangulares foram examinados com US-3D correlacionando com os achados cirúrgicos. Identificou-se o tipo de T (retilíneo ou curvo), OE e OI e distribuiu-se os pacientes em 3 grupos: GI:OE e OI localizados em HCA; GII:OE e OI localizados em HCP e GIII:OE e OI em posições opostas. Os achados foram correlacionados com a lei de Goodsall.

Resultados 74/151(49%) incluídos no GI, destes, 41(55%) homens(33/44% com trajeto retilíneo e 8/11% curvo) e 33(45%) mulheres(15/20%-retilíneo e 18/25%-curvo). No GII incluídos 68(45%), destes, 50(74%) homens(39/57%-retilíneo e 11/15%-curvo) e 18(26%) mulheres(14/20%-retilíneo e 04/8%-curvo). GIII = 9(6%) todos os trajetos curvos. A concordância entre o US-3D e os achados cirúrgicos foi de 98% para trajetos e 96% para o OI.

Conclusão Os achados ultrassonográficos permitiram correlacionar fístulas transesfinctéricas com trajetos retilíneos localizadas na hemicircunferência anterior, em homens, enquanto em mulheres a distribuição dos trajetos em curvo e retilíneo foram similares. Na hemicircunferência posterior não houve correlação em ambos os sexos.

Keywords

Transsphincteric fistula - Goodsall's rule - Three-dimensional anorectal ultrasonography

Palavras-chave

Fístula transesfinctérica - Teoria de Goodsall - Ultrassonografia anorretal tridimensional

Publication History

Received: 29 December 2014

Accepted: 20 February 2015

Article published online:
17 February 2021