Management of Perianal Crohn's Disease.
Journal
The American journal of gastroenterology
ISSN: 1572-0241
Titre abrégé: Am J Gastroenterol
Pays: United States
ID NLM: 0421030
Informations de publication
Date de publication:
01 08 2023
01 08 2023
Historique:
received:
13
03
2023
accepted:
10
05
2023
medline:
4
8
2023
pubmed:
19
5
2023
entrez:
19
5
2023
Statut:
ppublish
Résumé
Perianal Crohn's disease affects 25%-35% of patients with Crohn's disease and has proven to be one of the most difficult complications of the disease to treat. Patients with perianal Crohn's disease have lower health-related quality of life scores typically related to pain and fecal incontinence. In addition, patients with perianal Crohn's disease have higher rates of hospitalizations, surgeries, and overall healthcare costs. A multidisciplinary approach is necessary for the successful management of Crohn's disease with perianal fistula. Medical management is required to treat the underlying immune dysregulation to heal the luminal inflammation and the inflammation within the fistula tracts. Current options for medical therapy include biologics, dual therapy with thiopurines, therapeutic drug monitoring, and a close follow-up. Surgical management is critical to drain abscesses before immunosuppressive therapy and place setons when appropriate. Once the patient's inflammatory burden is well managed, definitive surgical therapies including fistulotomies, advancement flaps, and ligation of intersphincteric fistula tract procedures can be considered. Most recently, the use of stem cell therapy in the treatment of perianal fistula has given new hope to the cure of perianal fistula in Crohn's disease. This review will outline the most current data in the medical and surgical management of perianal Crohn's disease.
Identifiants
pubmed: 37207318
doi: 10.14309/ajg.0000000000002326
pii: 00000434-990000000-00753
doi:
Types de publication
Review
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1323-1331Informations de copyright
Copyright © 2023 by The American College of Gastroenterology.
Références
Schwartz DA, Loftus EV Jr., Tremaine WJ, et al. The natural history of fistulizing Crohn's disease in Olmsted County, Minnesota. Gastroenterology. 2002;122(4):875–80.
Park SH, Aniwan S, Scott Harmsen W, et al. Update on the natural course of fistulizing perianal Crohn's disease in a population-based cohort. Inflamm Bowel Dis. 2019;25(6):1054–60.
Brochard C, Rabilloud ML, Hamonic S, et al. Natural history of perianal Crohn's disease: Long-term follow-up of a population-based cohort. Clin Gastroenterol Hepatol<i>.</i> 2022;20(2):e102–e110.
Tsai L, McCurdy JD, Ma C, et al. Epidemiology and natural history of perianal Crohn's disease: A systematic review and meta-analysis of population-based Cohorts. Inflamm Bowel Dis. 2022;28(10):1477–84.
Adegbola SO, Dibley L, Sahnan K, et al. Burden of disease and adaptation to life in patients with Crohn's perianal fistula: A qualitative exploration. Health Qual Life Outcomes. 2020;18(1):370.
Vollebregt PF, van Bodegraven AA, Markus-de Kwaadsteniet TML, et al. Impacts of perianal disease and faecal incontinence on quality of life and employment in 1092 patients with inflammatory bowel disease. Aliment Pharmacol Ther. 2018;47(9):1253–60.
Panes J, Reinisch W, Rupniewska E, et al. Burden and outcomes for complex perianal fistulas in Crohn's disease: Systematic review. World J Gastroenterol. 2018;24(42):4821–34.
Palmieri C, Muller G, Kroesen AJ, et al. Perianal fistula-associated carcinoma in Crohn's disease: A multicentre retrospective case control study. J Crohn's Colitis. 2021;15(10):1686–93.
Parks AG, Gordon PH, Hardcastle JD. A classification of fistula-in-ano. Br J Surg. 1976;63(1):1–12.
American Gastroenterological Association Clinical Practice. American Gastroenterological Association medical position statement: Perianal Crohn's disease. Gastroenterology. 2003;125(5):1503–7.
Sandborn WJ, Fazio VW, Feagan BG, et al. AGA technical review on perianal Crohn's disease. Gastroenterology. 2003;125(5):1508–30.
Geldof J, Iqbal N, LeBlanc JF, et al. Classifying perianal fistulising Crohn's disease: An expert consensus to guide decision-making in daily practice and clinical trials. Lancet Gastroenterol Hepatol. 2022;7(6):576–84.
Brochard C, Rabilloud ML, Hamonic S, et al. Natural history of perianal Crohn's disease: Long-term follow-up of a population-based cohort. Clin Gastroenterol Hepatol. 2022;20(2):E102–E110.
Danielou M, Sarter H, Pariente B, et al. Natural history of perianal fistulising lesions in patients with elderly-onset Crohn's disease: A population-based study. J Crohn's Colitis. 2020;14(4):501–7.
Bruckner A, Werkstetter KJ, de Laffolie J, et al. Incidence and risk factors for perianal disease in pediatric Crohn disease patients followed in CEDATA-GPGE registry. J Pediatr Gastroenterol Nutr. 2018;66(1):73–8.
Adler J, Lin CC, Gadepalli SK, et al. Association between steroid-sparing therapy and the risk of perianal fistulizing complications among young patients with Crohn disease. Jama Netw Open. 2020;3(6).
Schwartz DA, Wiersema MJ, Dudiak KM, et al. A comparison of endoscopic ultrasound, magnetic resonance imaging, and exam under anesthesia for evaluation of Crohn's perianal fistulas. Gastroenterology. 2001;121(5):1064–72.
Brandt LJ, Bernstein LH, Boley SJ, et al. Metronidazole therapy for perineal Crohn's disease: A follow-up study. Gastroenterology. 1982;83(2):383–7.
Dejaco C, Harrer M, Waldhoer T, et al. Antibiotics and azathioprine for the treatment of perianal fistulas in Crohn's disease. Aliment Pharmacol Ther. 2003;18(11-12):1113–20.
West RL, van der Woude CJ, Hansen BE, et al. Clinical and endosonographic effect of ciprofloxacin on the treatment of perianal fistulae in Crohn's disease with infliximab: A double-blind placebo-controlled study. Aliment Pharmacol Ther. 2004;20(11-12):1329–36.
Dewint P, Hansen BE, Verhey E, et al. Adalimumab combined with ciprofloxacin is superior to adalimumab monotherapy in perianal fistula closure in Crohn's disease: A randomised, double-blind, placebo controlled trial (ADAFI). Gut. 2014;63(2):292–9.
Feuerstein JD, Ho EY, Shmidt E, et al. AGA clinical practice guidelines on the medical management of moderate to severe luminal and perianal fistulizing Crohn's disease. Gastroenterology. 2021;160(7):2496–508.
Pearson DC, May GR, Fick GH, et al. Azathioprine and 6-mercaptopurine in Crohn disease. A meta-analysis. Ann Intern Med. 1995;123(2):132–42.
Mahadevan U, Marion JF, Present DH. Fistula response to methotrexate in Crohn's disease: A case series. Aliment Pharmacol Ther. 2003;18(10):1003–8.
Present DH, Lichtiger S. Efficacy of cyclosporine in treatment of fistula of Crohn's disease. Dig Dis Sci. 1994;39(2):374–80.
Egan LJ, Sandborn WJ, Tremaine WJ. Clinical outcome following treatment of refractory inflammatory and fistulizing Crohn's disease with intravenous cyclosporine. Am J Gastroenterol. 1998;93(3):442–8.
Hanauer SB, Smith MB. Rapid closure of Crohn's disease fistulas with continuous intravenous cyclosporin A. Am J Gastroenterol. 1993;88(5):646–9.
Present DH, Lichtiger S. Efficacy of cyclosporine in treatment of fistula of Crohns-disease. Dig Dis Sci. 1994;39(2):374–80.
Petritsch W, Aichbichler B, Hinterleitner T, et al. Combination of cyclosporin, azathioprine and prednisolone for the treatment of fistulas in Crohn's disease. Gastroenterology. 1996;110(4):A990.
ONeill J, Pathmakanthan S, Goh J, et al. Cyclosporine A induces remission in fistulous Crohn's disease but relapse occurs upon cessation of treatment. Gastroenterology. 1997;112(4):A1056.
Sandborn WJ, Present DH, Isaacs KL, et al. Tacrolimus for the treatment of fistulas in patients with Crohn's disease: A randomized, placebo-controlled trial. Gastroenterology. 2003;125(2):380–8.
Gonzalez-Lama Y, Abreu L, Vera MI, et al. Long-term oral tacrolimus therapy in refractory to infliximab fistulizing Crohn's disease: A pilot study. Inflamm Bowel Dis. 2005;11(1):8–15.
Hart AL, Plamondon S, Kamm MA. Topical tacrolimus in the treatment of perianal Crohn's disease: Exploratory randomized controlled trial. Inflamm Bowel Dis. 2007;13(3):245–53.
Present DH, Rutgeerts P, Targan S, et al. Infliximab for the treatment of fistulas in patients with Crohn's disease. The New Engl J Med. 1999;340(18):1398–405.
Sands BE, Anderson FH, Bernstein CN, et al. Infliximab maintenance therapy for fistulizing Crohn's disease. New Engl J Med. 2004;350(9):876–85.
Gu B, Venkatesh K, Williams AJ, et al. Higher infliximab and adalimumab trough levels are associated with fistula healing in patients with fistulising perianal Crohn's disease. World J Gastroenterol. 2022;28(23):2597–608.
Papamichael K, Vande Casteele N, Jeyarajah J, et al. Higher postinduction infliximab concentrations are associated with improved clinical outcomes in fistulizing Crohn's disease: An ACCENT-II post hoc analysis. Am J Gastroenterol. 2021;116(5):1007–14.
Plevris N, Jenkinson PW, Arnott ID, et al. Higher anti-tumor necrosis factor levels are associated with perianal fistula healing and fistula closure in Crohn's disease. Eur J Gastroenterol Hepatol. 2020;32(1):32–7.
Strik AS, Lowenberg M, Buskens CJ, et al. Higher anti-TNF serum levels are associated with perianal fistula closure in Crohn's disease patients. Scand J Gastroenterol. 2019;54(4):453–8.
Yarur AJ, Kanagala V, Stein DJ, et al. Higher infliximab trough levels are associated with perianal fistula healing in patients with Crohn's disease. Aliment Pharmacol Ther. 2017;45(7):933–40.
Van Assche G, Vanbeckevoort D, Bielen D, et al. Magnetic resonance imaging of the effects of infliximab on perianal fistulizing Crohn's disease. Am J Gastroenterol. 2003;98(2):332–9.
Ardizzone S, Maconi G, Colombo E, et al. Perianal fistulae following infliximab treatment: Clinical and endosonographic outcome. Inflamm Bowel Dis. 2004;10(2):91–6.
Colombel JF, Sandborn WJ, Rutgeerts P, et al. Adalimumab for maintenance of clinical response and remission in patients with Crohn's disease: The CHARM trial. Gastroenterology. 2007;132(1):52–65.
Colombel JF, Schwartz DA, Sandborn WJ, et al. Adalimumab for the treatment of fistulas in patients with Crohn's disease. Gut. 2009;58(7):940–8.
Fu YM, Chen M, Liao AJ. A meta-analysis of adalimumab for fistula in Crohn's disease. Gastroenterol Res Pract. 2017;2017:1745692.
Lichtiger S, Binion DG, Wolf DC, et al. The CHOICE trial: Adalimumab demonstrates safety, fistula healing, improved quality of life and increased work productivity in patients with Crohn's disease who failed prior infliximab therapy. Alimentary Pharm Ther. 2010;32(10):1228–39.
Sirmai L, Pelletier AL, Gault N, et al. Relationship between clinical remission of perianal fistulas in Crohn's disease and serum adalimumab concentrations: A multi-center cross-sectional study. World J Gastroenterol . 2022;28(9):961–72.
Sandborn WJ, Feagan BG, Stoinov S, et al. Certolizumab pegol for the treatment of Crohn's disease. New Engl J Med. 2007;357(3):228–38.
Schreiber S, Khaliq-Kareemi M, Lawrance IC, et al. Maintenance therapy with certolizumab pegol for Crohn's disease. New Engl J Med. 2007;357(3):239–50.
Schreiber S, Lawrance IC, Thomsen OO, et al. Randomised clinical trial: Certolizumab pegol for fistulas in Crohn's disease - subgroup results from a placebo-controlled study. Aliment Pharmacol Ther. 2011;33(2):185–93.
Sandborn WJ, Gasink C, Gao LL, et al. Ustekinumab induction and maintenance therapy in refractory Crohn's disease. New Engl J Med. 2012;367(16):1519–28.
Feagan BG, Sandborn WJ, Gasink C, et al. Ustekinumab as induction and maintenance therapy for Crohn's disease. New Engl J Med. 2016;375(20):1946–60.
Godoy Brewer GM, Salem G, Afzal MA, et al. Ustekinumab is effective for perianal fistulising Crohn's disease: A real-world experience and systematic review with meta-analysis. BMJ Open Gastroenterol. 2021;8(1):e000702.
Attauabi M, Burisch J, Seidelin JB. Efficacy of ustekinumab for active perianal fistulizing Crohn's disease: A systematic review and meta-analysis of the current literature. Scand J Gastroenterol. 2021;56(1):53–8.
Feagan BG, Schwartz D, Danese S, et al. Efficacy of vedolizumab in fistulising Crohn's disease: Exploratory analyses of data from GEMINI 2. J Crohn's Colitis. 2018;12(5):621–6.
Schwartz DA, Peyrin-Biroulet L, Lasch K, et al. Efficacy and safety of 2 vedolizumab intravenous regimens for perianal fistulizing Crohn's disease: ENTERPRISE study. Clin Gastroenterol Hepatol. 2022;20(5):1059–67 e9.
Lansdorp CA, Buskens CJ, Gecse KB, et al. Hyperbaric oxygen therapy for the treatment of perianal fistulas in 20 patients with Crohn's disease: Results of the HOT-TOPIC trial after 1-year follow-up. United Eur Gastroenterol J. 2022;10(2):160–8.
Dulai PS, Gleeson MW, Taylor D, et al. Systematic review: The safety and efficacy of hyperbaric oxygen therapy for inflammatory bowel disease. Aliment Pharmacol Ther. 2014;39(11):1266–75.
Agrawal G, Borody T, Turner R, et al. Combining infliximab, anti-MAP and hyperbaric oxygen therapy for resistant fistulizing Crohn's disease. Futur Sci OA. 2015;1(4):FSO77.
Feitosa MR, Parra RS, Feres O, et al. Adjunctive hyperbaric oxygen therapy promotes successful healing in patients with refractory Crohn disease. Gastroenterology. 2016;150(4):S567–S568.
Camporesi EM, Bosco G. Mechanisms of action of hyperbaric oxygen therapy. Undersea Hyperb Med. 2014;41(3):247–52.
Fosen KM, Thom SR. Hyperbaric oxygen, vasculogenic stem cells, and wound healing. Antioxid Redox Signal. 2014;21(11):1634–47.
Hill GB, Osterhout S. Experimental effects of hyperbaric-oxygen on selected Clostridial species. 1. In-vitro studies. J Infect Dis. 1972;125(1):17.
Mader JT, Brown GI, Guckian JC, et al. A mechanism for the amelioration by hyperbaric-oxygen of experimental staphylococcal osteomyelitis in rabbits. J Infect Dis. 1980;142(6):915–22.
McCurdy J, Siw KCK, Kandel R, et al. The effectiveness and safety of hyperbaric oxygen therapy in various phenotypes of inflammatory bowel disease: Systematic review with meta-analysis. Inflamm Bowel Dis. 2022;28(4):611–21.
Abushamma S, Ballard DH, Smith RK, et al. Multidisciplinary management of perianal Crohn's disease. Curr Opin Gastroenterol. 2021;37(4):295–305.
Yang BL, Chen YG, Gu YF, et al. Long-term outcome of infliximab combined with surgery for perianal fistulizing Crohn's disease. World J Gastroenterol. 2015;21(8):2475–82.
Ferrante M, Siproudhis L, Poggioli G, et al. P801 treatment patterns of complex perianal fistula in Crohn's disease in five European countries: The PREFACE study, a retrospective chart review. J Crohn's Colitis. 2020;14(Suppl_1):S628.
Fichera A, Michelassi F. Surgical treatment of Crohn's disease. J Gastrointest Surg. 2007;11(6):791–803.
Feroz SH, Ahmed A, Muralidharan A, et al. Comparison of the efficacy of the various treatment modalities in the management of perianal Crohn's fistula: A review. Cureus. 2020;12(12):e11882.
Tanaka S, Matsuo K, Sasaki T, et al. Clinical advantages of combined seton placement and infliximab maintenance therapy for perianal fistulizing Crohn's disease: When and how were the seton drains removed? Hepatogastroenterology. 2010;57(97):3–7.
Gecse KB, Bemelman W, Kamm MA, et al. A global consensus on the classification, diagnosis and multidisciplinary treatment of perianal fistulising Crohn's disease. Gut. 2014;63(9):1381–92.
Williams JL, Shaffer VO. Modern management of perianal Crohn's disease: A review. Am Surg. 2021;87(9):1361–7.
Sangwan YP, Schoetz DJ Jr., Murray JJ, et al. Perianal Crohn's disease. Results of local surgical treatment. Dis Colon Rectum. 1996;39(5):529–35.
Farag AFA, Elbarmelgi MY, Mostafa M, et al. One stage fistulectomy for high anal fistula with reconstruction of anal sphincter without fecal diversion. Asian J Surg. 2019;42(8):792–6.
Murtaza G, Shaikh FA, Chawla T, et al. Fistulotomy versus fistulectomy for simple fistula in ano: A retrospective cohort study. J Pak Med Assoc. 2017;67(3):339–42.
Rojanasakul A, Pattanaarun J, Sahakitrungruang C, et al. Total anal sphincter saving technique for fistula-in-ano; the ligation of intersphincteric fistula tract. J Med Assoc Thai. 2007;90(3):581–6.
Wood T, Truong A, Mujukian A, et al. Increasing experience with the LIFT procedure in Crohn's disease patients with complex anal fistula. Tech Coloproctol. 2022;26(3):205–12.
Gingold DS, Murrell ZA, Fleshner PR. A prospective evaluation of the ligation of the intersphincteric tract procedure for complex anal fistula in patients with Crohn's disease. Ann Surg. 2014;260(6):1057–61.
Stellingwerf ME, van Praag EM, Tozer PJ, et al. Systematic review and meta-analysis of endorectal advancement flap and ligation of the intersphincteric fistula tract for cryptoglandular and Crohn's high perianal fistulas. BJS Open. 2019;3(3):231–41.
Soltani A, Kaiser AM. Endorectal advancement flap for cryptoglandular or Crohn's fistula-in-ano. Dis Colon Rectum. 2010;53(4):486–95.
Moy J, Bodzin J. Carbon dioxide laser ablation of perianal fistulas in patients with Crohn's disease: Experience with 27 patients. Am J Surg. 2006;191(3):424–7.
Wilhelm A, Fiebig A, Krawczak M. Five years of experience with the FiLaC™ laser for fistula-in-ano management: Long-term follow-up from a single institution. Tech Coloproctol. 2017;21(4):269–76.
Meinero P, Mori L. Video-assisted anal fistula treatment (VAAFT): A novel sphincter-saving procedure for treating complex anal fistulas. Tech Coloproctol. 2011;15(4):417–22.
Adegbola SO, Sahnan K, Tozer PJ, et al. Symptom amelioration in Crohn's perianal fistulas using video-assisted anal fistula treatment (VAAFT). J Crohn's Colitis. 2018;12(9):1067–72.
Zabot GP, Cassol O, Saad-Hossne R, et al. Modern surgical strategies for perianal Crohn's disease. World J Gastroenterol. 2020;26(42):6572–81.
Kotze PG, Shen B, Lightner A, et al. Modern management of perianal fistulas in Crohn's disease: Future directions. Gut. 2018;67(6):1181–94.
Garcia-Olmo D, Garcia-Arranz M, Garcia LG, et al. Autologous stem cell transplantation for treatment of rectovaginal fistula in perianal Crohn's disease: A new cell-based therapy. Int J Colorectal Dis. 2003;18(5):451–4.
Herreros MD, Garcia-Arranz M, Guadalajara H, et al. Autologous expanded adipose-derived stem cells for the treatment of complex cryptoglandular perianal fistulas: A phase III randomized clinical trial (FATT 1: Fistula advanced therapy trial 1) and long-term evaluation. Dis Colon Rectum. 2012;55(7):762–72.
Panés J, García-Olmo D, Van Assche G, et al. Expanded allogeneic adipose-derived mesenchymal stem cells (Cx601) for complex perianal fistulas in Crohn's disease: A phase 3 randomised, double-blind controlled trial. Lancet. 2016;388(10051):1281–90.
Panés J, García-Olmo D, Van Assche G, et al. Long-term efficacy and safety of stem cell therapy (Cx601) for complex perianal fistulas in patients with Crohn's disease. Gastroenterology. 2018;154(5):1334–42.e4.
Ciccocioppo R, Bernardo ME, Sgarella A, et al. Autologous bone marrow-derived mesenchymal stromal cells in the treatment of fistulising Crohn's disease. Gut. 2011;60(6):788–98.
Dietz AB, Dozois EJ, Fletcher JG, et al. Autologous mesenchymal stem cells, applied in a bioabsorbable matrix, for treatment of perianal fistulas in patients with Crohn's disease. Gastroenterology. 2017;153(1):59–62.e2.
Pogacnik JS, Salgado G. Perianal Crohn's disease. Clin Colon Rectal Surg. 2019;32(5):377–85.
Lightner AL, Regueiro M. Anorectal strictures in complex perianal CD: How to approach? Clin Colon Rectal Surg. 2022;35(1):44–50.
Sandborn WJ, Fazio VW, Feagan BG, et al. AGA technical review on perianal Crohn's disease. Gastroenterology. 2003;125(5):1508–30.
Shen B, Kochhar G, Navaneethan U, et al. Practical guidelines on endoscopic treatment for Crohn's disease strictures: A consensus statement from the global interventional inflammatory bowel disease group. Lancet Gastroenterol Hepatol. 2020;5(4):393–405.
Fleshner PR, Schoetz DJ Jr, Roberts PL, et al. Anal fissure in Crohn's disease: A plea for aggressive management. Dis Colon Rectum. 1995;38(11):1137-43.
Wolkomir AF, Luchtefeld MA. Surgery for symptomatic hemorrhoids and anal fissures in Crohn's disease. Dis Colon Rectum. 1993;36(6):545.
D'Ugo S, Franceschilli L, Cadeddu F, et al. Medical and surgical treatment of haemorrhoids and anal fissure in Crohn's disease: A critical appraisal. BMC Gastroenterol. 2013;13:47.
Eglinton TW, Barclay ML, Gearry RB, et al. The spectrum of perianal Crohn's disease in a population-based cohort. Dis Colon Rectum. 2012;55(7):773–7.
Lightner AL, Kearney D, Giugliano D, et al. Excisional hemorrhoidectomy: Safe in patients with Crohn's disease?. Inflamm Bowel Dis. 2020;26(9):1390–3.
Yamamoto T, Allan RN, Keighley MR. Effect of fecal diversion alone on perianal Crohn's disease. World J Surg 2000;24(10):1258–62; discussion 1262-3.
Singh S, Ding NS, Mathis KL, et al. Systematic review with meta-analysis: Faecal diversion for management of perianal Crohn's disease. Aliment Pharmacol Ther. 2015;42(7):783–92.
Lightner AL. Perianal Crohn's disease. Dis Colon Rectum. 2020;63(8):1023–6.
Singh B, McC Mortensen NJ, Jewell DP, et al. Perianal Crohn's disease. Br J Surg. 2004;91(7):801–14.
Maeda Y, Heyckendorff-Diebold T, Tei TM, et al. Gracilis muscle transposition for complex fistula and persistent nonhealing sinus in perianal Crohn's disease. Inflamm Bowel Dis. 2011;17(2):583–9.
Beckingham IJ, Spencer JA, Ward J, et al. Prospective evaluation of dynamic contrast enhanced magnetic resonance imaging in the evaluation of fistula in ano. Br J Surg. 1996;83(10):1396–8.
Koelbel G, Schmiedl U, Majer MC, et al. Diagnosis of fistulae and sinus tracts in patients with Crohn disease: Value of MR imaging. AJR Am J Roentgenol. 1989;152(5):999–1003.
Makowiec F, Laniado M, Jehle EC, et al. Magnetic resonance imaging in perianal Crohn's disease. Inflamm Bowel Dis. 1995;1(4):256–65.
Ng SC, Plamondon S, Gupta A, et al. Prospective evaluation of anti-tumor necrosis factor therapy guided by magnetic resonance imaging for Crohn's perineal fistulas. Am J Gastroenterol. 2009;104(12):2973–86.
Spencer JA, Chapple K, Wilson D, et al. Outcome after surgery for perianal fistula: Predictive value of MR imaging. AJR Am J roentgenol. 1998;171(2):403–6.
Orsoni P, Barthet M, Portier F, et al. Prospective comparison of endosonography, magnetic resonance imaging and surgical findings in anorectal fistula and abscess complicating Crohn's disease. Br J Surg. 1999;86(3):360–4.
Schwartz DA, White CM, Wise PE, et al. Use of endoscopic ultrasound to guide combination medical and surgical therapy for patients with Crohn's perianal fistulas. Inflamm Bowel Dis. 2005;11(8):727–32.
Spradlin NM, Wise PE, Herline AJ, et al. A randomized prospective trial of endoscopic ultrasound to guide combination medical and surgical treatment for Crohn's perianal fistulas. Am J Gastroenterol. 2008;103(10):2527–35.
Tio TL, Mulder CJ, Wijers OB, et al. Endosonography of peri-anal and peri-colorectal fistula and/or abscess in Crohn's disease. Gastrointest Endosc. 1990;36(4):331–6.
Shen B. Chapter 7—endoscopic evaluation of perianal Crohn's disease. In: Shen B (ed). Atlas of Endoscopy Imaging in Inflammatory Bowel Disease. Academic Press, 2020, pp 77–95.