Level of highest mean resting pressure segment in the anal canal. A quantitative assessment of anal sphincter function.
OBJECTIVE
Even with the development of new technologies, the mechanism of fecal continence is still not completely understood. This study evaluates the relative position of the highest mean resting pressure (HMRP) in the anal canal and its correlation with function in incontinent patients and in controls.


METHODS
Sixteen incontinent patients (mean age, 47.1 +/- 13.9 (range, 18-63) years; 12 female) and 16 controls (mean age, 35.4 +/- 8.7 (range, 24-58) years; 12 female) were studied using a water-perfused eight-port radial catheter computer-assisted vectromanometry. Position of the HMRP was analyzed in relation to the anal verge (D1) and to the proximal functional border of the anal canal (D2).


RESULTS
Controls had HMRP located more distally in the anal canal, because D2 was significantly higher than D1 (mean, 3.45 +/- 0.75 vs. 1.81 +/- 0.63 cm; p + 0.001). For incontinent patients, D1 and D2 were similar (mean, 1.86 +/- 0.75 vs. 2.08 +/- 1.11 cm; not significant). Comparison of the relative position of the HMRP between patients and controls showed a more proximal location for incontinent patients than controls (mean, 49.1 +/- 12.1 percent vs. 35.4 +/- 10.2 percent; p = 0.002).


CONCLUSIONS
Position of the HMRP is significantly more proximal for incontinent patients than for controls, and measurement of the distance from the anal verge to the HMRP in relation to the full length of the anal canal may represent another way to quantitatively assess anal sphincter function.
Goes
R N
RN
Department of Surgery, Division of Colon and Rectal Surgery, University of Southern California, Los Angeles, California, 90033-4612, USA
Simons
A J
AJ
Beart
R W
RW
D000293:Adolescent; D000328:Adult; D001003:Anal Canal / Q000502:physiology / Q000503:physiopathology*; D016022:Case-Control Studies; D003936:Diagnosis, Computer-Assisted; D005242:Fecal Incontinence / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D011312:Pressure