Abstract
PURPOSE: To obtain high resolution images of the anal sphincter and adjacent anorectum using an endoanal coil in patients with sepsis, trauma, and low rectal tumors and to compare imaging appearances with findings at time of surgery. PATIENTS AND METHODS: A cylindrical saddle geometry coil (diameter, 9 mm; length, 75 mm) was used to examine 30 patients (mean age, 53.6 years). Pathologies included perianal sepsis (10 patients), obstetric trauma (7 patients), and low rectal tumors (13 patients). Imaging was performed on an 0.5-T Picker Asset or 1.0-T Picker HPQ Vista (Picker International, Highland Heights, OH). T 1 and T 2 weighted and short inversion time inversion recovery transverse images and T 1 weighted coronal images were obtained. Intravenous gadopentetate dimeglumine (0.1 mmol/kg) was given to all patients with suspected infection and neoplasms. RESULTS: Abscesses and fistulas identified using magnetic resonance imaging (MRI) in patients with perianal sepsis were confirmed at surgery in all cases; site of fistulous internal opening into the anal canal was correctly identified in 80 percent of cases. Extent of sphincter tear was correctly assessed on endoanal MRI in all patients with obstetric trauma when compared with surgical findings. Tumor invasion of anal sphincter was seen in 38.5 percent of low rectal carcinomas. CONCLUSIONS: MRI with an endoanal coil provides detailed images of the site and extent of anal fistulas, sphincter tears, and local tumors and is of considerable value in preoperative assessment.
Article PDF
Similar content being viewed by others
References
Sultan AH, Kamm MA, Hudson CN, Thomas JM, Bartram CI. Anal sphincter disruption during vaginal delivery. N Engl J Med 1993;329:1905–11.
Sultan AH, Nicholas 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.
Sultan AH, Kamm MA, Hudson CN, Nicholas JR, Bertram CI. Endosonography of the anal sphincters: normal anatomy and comparison with manometry. Clin Radiol 1994;49:368–74.
Nielson MB, Pedersen JF, Hauge C, Rasmussen OO, Christiansen JC. Endosonography of the anal sphincter: findings in healthy volunteers. AJR Am J Roentgenol 1991;157:1199–202.
Schafer A, Enck P, Fürst G, Kahn T, Frieling T, Lubke HJ. Anatomy of the anal sphincters: comparison of anal endosonography to magnetic resonance imaging. Dis Colon Rectum 1994;37:777–81.
deSouza 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.
Puni R, Hall AS, Courts GA, deSouza NM. Development of an insertable surface coil for MRI of the anal sphincter [abstract]. Br J Radiol 1994;68:679.
Hussain SM, Stoker J, Kulper JW, Schouten WR, den Hollander JC, Lameris JC. MR imaging of anal sphincter complex with an endoanal coil: normal anatomy and pathology [abstract]. Radiology 1994;193:445.
deSouza NM, Puni R, Kmiot WA, Bartram CI, Hall AS, Bydder GM. MRI of the anal sphincter. J Comput Assist Tomogr 1995;19:745–51.
Parks AG, Gordon PH, Hardcastle JD. A classification of fistula-in-ano. Br J Surg 1976;63:1–12.
Lunniss PJ, Barker PG, Sultan AH,et al. Magnetic resonance imaging of fistula-in-ano. Dis Colon Rectum 1994;37:708–18.
Myhr GE, Myrvold HE, Nilsen G, Thoresen JE, Rinck PA. Perianal fistulas: use of MR imaging for diagnosis. Radiology 1994;191:545–9.
Tjandra JJ, Sissons GR. Magnetic resonance imaging facilitates assessment of perianal Crohns disease. Aust N Z J Surg 1994;64:470–4.
Marks CG, Ritchie JK. Anal fistulas at St. Marks Hospital. Br J Surg 1977;64:84–9.
Ani AN, Lagundoye SB. Radiological evaluation of anal fistulae: a prospective study of fistulagrams. Clin Radiol 1979;30:21–4.
Sainio P, Husa A. Fistula-in-ano: clinical features and long-term results of surgery in 199 adults. Acta Chir Scand 1985;151:169–76.
Kuijpers HC, Schulpen T. Fistulography for fistula-in-ano: is it useful? Dis Colon Rectum 1985;28:103–4.
Weisman RI, Orsay CP, Pearl RK, Abcarian H. The role of fistulography in fistula-in-ano: report of five cases. Dis Colon Rectum 1991;34:181–4.
Law PJ, Talbot RW, Bartram CI, Northover JM. Anal endosonography in the evaluation of peri-anal sepsis and fistula-in-ano. Br J Surg 1989;76:752–5.
Choen S, Burnett S, Bertram CI, Nicholls RJ. Comparison between anal endosonography and digital examination in the evaluation of anal fistulae. Br J Surg 1991;78:445–7.
Mulder CJ, Tio TL, Tytgat GN. Transrectal ultrasonography in the assessment of periano-rectal fistula and/or abscess in Crohn's disease [abstract]. Gastroenterology 1988;94:313A.
Schratter-Sehn AU, Lochs H, Vogelsang H, Schurawitzki H, Herold CH, Schratter M. Comparison of transrectal ultrasonography and computed tomography in the diagnosis of periano-rectal fistulae in patients with Crohn's disease [abstract], Gastroenterology 1992:102:691A.
Guillaumin E, Jeffery RB, Shea WJ, Willett-Asling C, Goldberg HI. Perirectal inflammatory disease: CT findings. Radiology 1986;161:1:53–7.
Yousem DM, Fishman EK, Jones B. Crohn's disease: perirectal and perianal findings at CT. Radiology 1988;167:331–4.
Barker PG, Luniss PJ, Armstrong P, Reznek RH, Cottam K, Phillips RK. Magnetic resonance imaging of fistula-in-ano: technique, interpretation and accuracy. Clin Radiol 1994;49:7–13.
Tio TL, Mulder CJ, Wijers OB, Sars PR, Tytgat GN. Endosonography of peri-anal and peri-colorectal fistula and/or abscess in Crohns disease. Gastrointest Endosc 1990;36:331–6.
Aronson MP, Lee RA, Berquist TH. Anatomy of anal sphincters and related structures in continent women studied with magnetic resonance imaging. Obstet Gynecol 1990;76:846–51.
Author information
Authors and Affiliations
Additional information
Supported by the Medical Research Council, United Kingdom.
Read at the meeting of the Radiological Society of North America, Chicago, Illinois, November 25 to December 1, 1995.
About this article
Cite this article
deSouza, N.M., Hall, A.S., Puni, R. et al. High resolution magnetic resonance imaging of the anal sphincter using a dedicated endoanal coil. Dis Colon Rectum 39, 926–934 (1996). https://doi.org/10.1007/BF02053993
Issue Date:
DOI: https://doi.org/10.1007/BF02053993