Abstract
PURPOSE: The aim of this study was to test the hypothesis that a delay in pudendal nerve conduction as measured by pudendal nerve terminal motor latency should be associated with atrophy of the external anal sphincter as measured using endoanal ultrasound. METHODS: Sixty-two adult females (median age, 58.9 (range, 22–88) years) presenting for evaluation of fecal incontinence with no evidence of an external anal sphincter tear on ultrasound were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Four measurements were made in the transverse plane—the external anal sphincter thickness in the midanal canal at the 6 o'clock and 9 o'clock positions, the internal sphincter at the 9 o'clock position, and the external anal sphincter in the low canal at the 9 o'clock position. Pudendal nerve terminal motor latency was measured using a transrectal nerve stimulation technique with measurement of the evoked muscle response. RESULTS: Although there was a trend toward thinner external sphincter muscles in those with bilateral prolonged pudendal nerve terminal motor latency, independent sample t-tests and Pearson correlation coefficients showed no statistically significant relationship (right pudendal nerve terminal motor latency:P=0.083, 0.184, 0.128, 0.910;r=0.228, 0.175, −0.201, −0.015; left pudendal nerve terminal motor latency:P=0.946, 0.276, 0.510, 0.123;r=−0.009, −0.143, −0.087, −0.201). CONCLUSIONS: No statistically significant relationship between ultrasound-measured anal sphincter muscle thickness and pudendal nerve terminal motor latency was identified. Although a trend was suggested that could be further evaluated by a study with a larger sample size and a control group with asymptomatic patients, the small differences in muscle thickness involved and the difficulties in measurement suggest that the establishment of clinically useful ultrasound criteria for the detection of the neuropathic anal sphincter complex is unlikely.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Parks AG, Swash M, Urick H. Sphincter denervation in anorectal incontinence and rectal prolapse. Gut 1977;18:656–65.
Roig JV, Villoslada C, Lledo S,et al. Prevalence of pudendal neuropathy in fecal incontinence: results of a prospective study. Dis Colon Rectum 1995;38:952–8.
Vaccaro CA, Cheong DM, Wexner SD,et al. Pudendal neuropathy in evacuatory disorders. Dis Colon Rectum 1995;38:166–71.
Vernava AM III, Longo WE, Daniel GL. Pudendal neuropathy and the importance of EMG evaluation of fecal incontinence. Dis Colon Rectum 1993;36:23–7.
Rieger NA, Sarre RG, Saccone GT, Schloithe AC, Wattchow DA. Correlation of pudendal nerve terminal motor latency with the results of anal manometry. Int J Colorectal Dis 1997;12:303–7.
Cheong DM, Vaccaro CA, Salanga VD, Wexner SD, Phillips RC, Hanson MR. Electrodiagnostic evaluation of fecal incontinence. Muscle Nerve 1995;18:612–9.
Sangwan YP, Coller JA, Barrett RC, Murray JJ, Roberts PL, Schoetz DJ Jr. Prospective comparative study of abnormal distal rectoanal excitatory reflex, pudendal nerve terminal motor latency, and single fiber density as markers of pudendal neuropathy. Dis Colon Rectum 1996;39:794–8.
Wexner SD, Marchetti F, Salanga VD, Corredor CR, Jagelman DG. Neurophysiologic assessment of the anal sphincters. Dis Colon Rectum 1991;34:606–12.
Tjandra JJ, Milsom JW, Schroeder T, Fazio VW. Endoluminal ultrasound is preferable to electromyography in mapping anal sphincteric defects. Dis Colon Rectum 1993;36:689–92.
Meyenberger C, Bertschinger P, Zala GF, Buchmann P. Anal sphincter defects in fecal incontinence: correlation between endosonography and surgery. Endoscopy 1996;28:217–24.
Deen KI, Kumar D, Williams JG, Olliff J, Keighley MR. Anal sphincter defects. Correlation between endoanal ultrasound and surgery. Ann Surg 1993;218:201–5.
Sentovich SM, Wong WD, Blatchford GJ. Accuracy and reliability of transanal ultrasound for anterior anal sphincter injury. Dis Colon Rectum 1998;41:1000–4.
Personius KE, Arbas EA. Muscle degeneration following remote injury. J Neurobiol 1998;36:497–508.
Sultan AH, Kamm MA, Hudson CN, Nicholls JR, Bartram CI. Endosonography of the anal sphincters: normal anatomy and comparison with manometry. Clin Radiol 1994;49:368–74.
Kiff ES, Swash M. Slowed conduction in the pudendal nerves in idiopathic (neurogenic) faecal incontinence. Br J Surg 1984;71:614–6.
De Souza NM, Kmiot Wa, Puni R,et al. High resolution magnetic resonance imaging of the anal sphincter using an internal coil. Gut 1995;37:284–7.
Nielsen MB, Hauge C, Rasmussen OO, Sorensen M, Pedersen JF, Christiansen J. Anal sphincter size measured by endosonography in healthy volunteers. Effect of age, sex and parity. Acta Radiol 1992;33:453–6.
Hussain SM, Stoker J, Lameris JS. Anal sphincter complex: endoanal MR imaging of normal anatomy. Radiology 1995;197:671–7.
De Souza NM, Puni R, Zbar A, Gilderdale DJ, Coutts GA, Krausz T. MR imaging of the anal sphincter in multiparous women using an endoanal coil: correlation with in vitro. AJR Am J Roentgenol 1996;167:1465–71.
Schafer A, Enck P, Furst G, Kahn Th, Frieling T, Lubke HJ. Anatomy of the anal sphincters: comparison of anal endosonography to magnetic resonance imaging. Dis Colon Rectum 1994;37:777–81.
Alexander AA, Miller LS, Liu J-B, Feld RI, Goldberg BB. High-resolution endoluminal sonography of the anal sphincter complex. J Ultrasound Med 1994;13:281–4.
Sultan AH, Nicholls RJ, Kamm MA, Hudson CN, Beynon J, Bartram CI. Anal endosonography and correlation within vitro andin vivo anatomy. Br J Surg 1993;80:508–11.
Felt-Bersma RJ, Cuesta MA, Koorevaar M,et al. Anal endosonography: relation with anal manometry and neurophysiologic tests. Dis Colon Rectum 1992;35:944–9.
Lubowski DZ, Jones PN, Swash M, Henry MM. Asymmetrical pudendal nerve damage in pelvic floor disorders. Int J Colorectal Dis 1988;3:59–63.
Wunderlich M, Swash M. The overlapping innervation of the two sides of the external anal sphincter by the pudendal nerve. J Neurol Sci 1983;59:97–109.
Burnett SJ, Spence-Jones C, Speakman CT, Kamm MA, Hudson CH, Bartram CI. Unsuspected sphincter damage following childbirth revealed by anal endosonography. Br J Radiol 1991;64:225–7.
Snooks SJ, Henry MM, Swash M. Anorectal incontinence and rectal prolapse: differential assessment of the innervation to puborectalis and external anal sphincter muscles. Gut 1985;26:470–6.
Author information
Authors and Affiliations
About this article
Cite this article
Voyvodic, F., Schloithe, A.C., Wattchow, D.A. et al. Delayed pudendal nerve conduction and endosonographic appearance of the anal sphincter complex. Dis Colon Rectum 43, 1689–1694 (2000). https://doi.org/10.1007/BF02236851
Issue Date:
DOI: https://doi.org/10.1007/BF02236851