Chronic anal fissure: morphometric analysis of the anal canal at 3.0 Tesla MR imaging.
OBJECTıVE: To compare the morphometric data relating to the muscular structures of the anal canal, in patients with chronic anal fissure and in control group, examined at a 3.0 Tesla MR system.



Forty-seven consecutive patients with chronic anal fissure and randomly selected 40 patients who had no claims for perianal disease during their life time were included in the study. T2-weighted sagittal, high-resolution (HR) T2-weighted, and contrast-enhanced fat-suppressed T1-weighted oblique axial and oblique coronal images were retrospectively analyzed by two observers in consensus. Thickness of sphincteric muscles, anal canal length, anorectal angle, thickness of anococcygeal ligament, depth of Minor triangle, width between subcutaneous sphincters, vascularity of posterior commissure, visibility of posterosuperior projection of external sphincter, and angle between the distal anal canal and posterosuperior projection of external sphincter (H angle) in patients and in controls were compared and analyzed using t test, Mann-Whitney U test, and Spearman correlation.



The patients with chronic anal fissure had longer anal canal (51.50 mm ± 0.91 vs. 44.11 mm ± 0.71; p = 0.000), thicker internal anal sphincter muscle at mid-anal level (4.18 ± 0.15 vs. 3.39 ± 0.07; p = 0.007), and wider space between subcutaneous external sphincters (11.39 ± 0.50 vs. 6.89 ± 0.22; p = 0.000). In patients, there was a positive correlation between H angle and external sphincter thickness at proximal (r = 0.347; p = 0.021), middle (r = 0427; p = 0.000), and distal (r = 0.518; p = 0.000)) levels of the anal canal. CONCLUSıON: 3.0 Tesla MR imaging provides detailed information about the morphometric changes in the anal sphincter muscles in patients with chronic anal fissure.
Department of Radiology, School of Medicine, Ankara University, Talatpaşa Bulvarı, Sıhhiye, 06100, Ankara, Turkey. ayse.erden@medicine.ankara.edu.tr.
Ayşe
A
Erden
Department of Radiology, School of Medicine, Ankara University, Talatpaşa Bulvarı, Sıhhiye, 06100, Ankara, Turkey.
Elif
E
Peker
Department of Biostatistics, School of Medicine, Ankara University, Ankara, Turkey.
Zeynep Bıyıklı
ZB
Gençtürk
D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D005401:Fissure in Ano / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
D003287:Contrast Media
Anal canal; Anal fissure; Anatomy; MR imaging