La radiologia medica

, Volume 117, Issue 5, pp 759–771 | Cite as

Three-dimensional anal endosonography in depicting anal-canal anatomy

  • A. Reginelli
  • Y. Mandato
  • C. Cavaliere
  • N. L. Pizza
  • A. Russo
  • S. Cappabianca
  • L. Brunese
  • A. Rotondo
  • R. Grassi
Abdominal Radiology / Radiologia Addominale



This report describes the advantages of 3D anal endosonography in depicting the normal anatomy of the anal canal in relation to sex and age.

Materials and methods

A retrospective study was performed of 85 patients, 33 men and 52 women, previously examined with 3D anal ultrasound (US) for clinically suspected anorectal disease but found to be negative. The examinations were performed with a Bruel and Kjaer US system with a 2050 transducer, scanning from the anorectal junction to the subcutaneous portion of the external anal sphincter (EAS). The 3D reconstructions provided an estimation of sphincter length in the anterior and posterior planes, and axial 2D images enabled calculation of the thickness of the internal anal sphincter (IAS) and EAS in the anterior, posterior and lateral transverse planes.


Distribution of the sphincter complex is asymmetric in both sexes: the EAS and IAS are significantly shorter in females, especially in the anterior longitudinal plane (p=0.005 and p<0.001, respectively). EAS and IAS thickness increases with age, especially the lateral IAS (R2=0.37, p<0.001) and the posterior EAS (R2=0.29, p=0.01).


A good knowledge of anal-canal anatomy is essential to detect sphincter abnormalities when assessing pelvic floor dysfunction.


3D anal endosonography Anal sphincter Anal canal anatomy 

Rappresentazione anatomica del canale anale con ultrasonografia (US) endoanale 3D



Scopo del presente lavoro è stato documentare la rappresentazione anatomica normale del canale anale attraverso l’ultrasonografia (US) endoanale 3D, in relazione al sesso e all’età.

Materiali e metodi

In uno studio retrospettivo sono stati selezionati 85 soggetti, di cui 33 maschi e 52 femmine, sottoposti precedentemente ad US endoanale 3D per sospetto clinico di patologia dell’ano-retto distale ma risultati essere tutti negativi all’esame ultrasonografico. Gli esami sono stati eseguiti con apparecchio dedicato Bruel e Kjaer, con trasduttore tipo 2050 e scansioni dalla giunzione ano-rettale alla porzione più superficiale dello sfintere anale esterno (SAE). Nell’immediato postprocessing sono stati stimati la lunghezza degli sfinteri nei piani anteriore e posteriore e lo spessore anteriore, laterale e posteriore dello sfintere anale interno (SAI) e del SAE.


La distribuzione della muscolatura del canale anale risulta asimmetrica in entrambi i sessi: la lunghezza di SAI e SAE è significativamente più breve nelle donne, specie lungo il piano longitudinale mediano anteriore (p=0,005 e p<0,001, rispettivamente). Inoltre, lo spessore di entrambi gli sfinteri presenta una tendenza all’accrescimento proporzionale all’età del paziente, soprattutto nella porzione laterale per il SAI (R2=0,37, p<0,001) e posteriore per il SAE (R2=0,29, p=0,01).


La conoscenza precisa delle componenti anatomiche muscolo-legamentose del canale anale è alla base della identificazione delle alterazioni sfinteriali utili alla comprensione dei disturbi del pavimento pelvico.

Parole chiave

Ultrasonografia endoanale 3D Sfintere anale Anatomia del canale anale 


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  1. 1.
    Bogduk N (1996) Issues in anatomy: the external anal sphincter revisited. Aust NZJ Surg 66:626–629CrossRefGoogle Scholar
  2. 2.
    Nielsen MB, Pedersen JF, Hauge C et al (1991) Endosonography of the anal sphincter: findings in healthy volunteers. AJR Am J Roentgenol 157:1199–1202PubMedGoogle Scholar
  3. 3.
    Brunese L, Amitrano M, Gargano V et al (1996) Anal endosonography: the study technique and the correlations between the normal and echographic anatomy. Radiol Med 91:253–257PubMedGoogle Scholar
  4. 4.
    Brunese L, Amitrano M, Gargano V et al (1996) Role of anal endosonography in inflammation and trauma of the anal canal. Radiol Med 92:742–747PubMedGoogle Scholar
  5. 5.
    Bartram CI, Frudinger A (1997) Handbook of anal sonography, 1st edn. Wrightsone Biomedical, PetersfieldGoogle Scholar
  6. 6.
    Frudinger A, Bartram CI, Halligan S et al (1998) Examination techniques for endosonography of the anal canal. Abdom Imaging 23:301–303PubMedCrossRefGoogle Scholar
  7. 7.
    Frudinger A, Halligan S, Bartram CI et al (2002) Female anal sphincter: age-related differences in asymptomatic volunteers with high-frequency endoanal US. Radiology 224:417–423PubMedCrossRefGoogle Scholar
  8. 8.
    Pomerri F, Dodi G, Pintacuda G et al (2010) Anal endosonography and fistulography for fistula in ano. Radiol Med 115:771–783PubMedCrossRefGoogle Scholar
  9. 9.
    Williams AB, Bartram CI, Halligan S et al (2001) Anal sphincter damage after vaginal delivery using three-dimensional endosonography. Obstet Gynecol 97:770–775PubMedCrossRefGoogle Scholar
  10. 10.
    Williams AB, Cheetham MJ, Bartram CI et al (2000) Gender differences in the longitudinal pressure profile of the anal canal related to anatomical structure as demonstrated on three-dimensional anal endosonography. Br J Surg 87:1674–1679PubMedCrossRefGoogle Scholar
  11. 11.
    Gold DM, Bartram CI, Halligan S et al (1999) Three-dimensional endoanal sonography in assessing anal canal injury. Br J Surg 86:365–370PubMedCrossRefGoogle Scholar
  12. 12.
    Thakar R and Fenner DE (2007) Anatomy of the perineum and the anal sphincter. In: Sultan AH, Thakar R, Fenner D (eds) Perineal and anal sphincter trauma. Springer, London, pp 1–12CrossRefGoogle Scholar
  13. 13.
    Damon H, Henry L, Roman S et al (2003) Influence of rectal prolapse on the asymmetry of the anal sphincter in patients with anal incontinence. BMC Gastroenterology 3:23–30PubMedCrossRefGoogle Scholar
  14. 14.
    Santoro GA, Wieczorek AP, Dietz HP et al (2011) State of the art: an integrated approach to pelvic floor ultrasonography. Ultrasound Obstet Gyneco 37:381–396CrossRefGoogle Scholar
  15. 15.
    Bartram CI (2008) Endoanal ultrasound. In: Stoker J, Taylor SA, De Lancey JOL (eds) Pelvic floor disorders. Springer, Berlin, pp 101–113CrossRefGoogle Scholar
  16. 16.
    Santoro GA, Di Falco G (2006) Endosonographic anatomy of the normal anal canal. In: Santoro GA, Di Falco G (eds) Benign anorectal diseases. Diagnosis with endoanal and endorectal ultrasonography and new treatment options. Springer-Verlag, Milan, pp 35–52Google Scholar
  17. 17.
    Santoro GA, Di Falco G (2010) Endoanal and endorectal ultrasonography: methodology and normal pelvic floor anatomy. In: Santoro GA, Wieczorek AP, Bartram CI (eds) Pelvic floor disorders. Springer, London, pp 91–102CrossRefGoogle Scholar
  18. 18.
    Stoker J, Bartram CI, Halligan S (2002) Imaging of the posterior pelvic floor. Eur Radiol 12:779–788PubMedCrossRefGoogle Scholar
  19. 19.
    BK Medical Group (2008) 3D Anorectal ultrasound. Anorectal endosonography. Application NoteGoogle Scholar
  20. 20.
    Starck M, Bohe M, Fortling B et al (2005) Endosonography of the anal sphincter in women of different ages and parity. Ultrasound Obstet Gynecol 25:169–176PubMedCrossRefGoogle Scholar
  21. 21.
    West RL, Felt-Bersma RJF, Hansen BE et al (2005) Volume measurements of the anal sphincter complex in healthy controls and fecal-incontinent patients with a three-dimensional reconstruction of endoanal ultrasonography images. Dis Colon Rectum 48:540–548PubMedCrossRefGoogle Scholar
  22. 22.
    Regadas FSP, Regadas SMM, Lima DMR et al (2007) Anal canal anatomy showed by three-dimensional anorectal ultrasonography. Surg Endosc 21:2207–2211PubMedCrossRefGoogle Scholar
  23. 23.
    Knowles AM, Knowles CH, Scott SM et al (2008) Effect of age and gender on three-dimensional endoanal ultrasonography measurements: development of normal ranges. Tech Coloproctol 12:323–329PubMedCrossRefGoogle Scholar
  24. 24.
    Esclapez-Valero JP and Garcia-Botello S (2005) Current utility of endoanal ultrasound in the diagnosis of benign proctological disease. Cir Esp 78:8–14PubMedCrossRefGoogle Scholar
  25. 25.
    Regadas SM, Regadas FS, Rodrigues LV et al (2005) Importance of the three-dimensional ultrasound in the anorectal evaluation. Arq Gastroenterol 42:226–232PubMedCrossRefGoogle Scholar
  26. 26.
    Rotondo A, Romano S, D’Andrea A et al (2006) Patologia del perineo posteriore. In: Gugliemi G, Schiavon F, Cammarota T (eds) Radiologia geriatrica. Springer-Verlag Italia, Milano, pp 425–436CrossRefGoogle Scholar
  27. 27.
    Norderval S, Dehli T, Vonen B (2009) Three-dimensional endoanal ultrasonography: intraobserver and interobserver agreement using scoring systems for classification of anal sphincter defects. Ultrasound Obstet Gynecol 33:337–343PubMedCrossRefGoogle Scholar
  28. 28.
    Granata V, Mandato Y, Russo A et al (2010) Imaging delle disfunzioni del pavimento pelvico. In: Blandino A, Rotondo A, Danza F, Menchi I, Pozzi Mucelli R (eds) Imaging dell’apparato uro-genitale: patologia non oncologica, Springer-Verlag Italia, Milano, pp 175–191Google Scholar
  29. 29.
    Reginelli A, Pezzullo MG, Scaglione M et al (2008) Gastrointestinal disorders in elderly patients. Radiol Clin North Am 46:755–771PubMedCrossRefGoogle Scholar
  30. 30.
    Regadas FSP, Murad-Regadas SM, Wexner SD et al (2007) Anorectal three-dimensional endononography and anal manometry in assessing anterior rectocele in women a new pathogenesis concept and the basic surgical principle. Colorectal Dis 9:80–85PubMedCrossRefGoogle Scholar
  31. 31.
    Bollard RC, Gardiner A, Lindow S et al (2002) Normal female anal sphincter: difficulties in interpretation explained. Dis Colon Rectum 45:171–175PubMedCrossRefGoogle Scholar
  32. 32.
    Engin G (2006) Endosonographic imaging of anorectal disease. J Ultrasound Med 25:57–73PubMedGoogle Scholar
  33. 33.
    Berton F, Gola G, Wilson RS (2007) Sonography of benign conditions of the anal canal: an update. AJR Am J Roentgenol 189:765–773PubMedCrossRefGoogle Scholar
  34. 34.
    Gregory WT, Boyles SH, Simmons K et al (2006) External anal sphincter volume measurements using three-dimensional endoanal ultrasound. Am J Obstet Gynecol 194:1243–1248PubMedCrossRefGoogle Scholar
  35. 35.
    Santoro GA, Fortling BEE (2006) The advantages of volume rendering in three-dimensional endosonography of the anorectum. Dis Colon Rectum 50:359–368CrossRefGoogle Scholar
  36. 36.
    Saranovic D, Barisic G, Krivokapic Z et al (2007) Endoanal ultrasound evaluation of anorectal diseases and disorders: technique, indications, results and limitations. Eur J Radiol 61:480–489PubMedCrossRefGoogle Scholar
  37. 37.
    Savoy-Collet C, Konig E, Dacher JN (2008) Radiologic evaluation of pelvic floor disorders. Gastroenterol Clin N Am 37:553–567CrossRefGoogle Scholar
  38. 38.
    De la Portilla F, Lopez-Alonso M (2009) Endosonography of the anal canal: findings in children. Dis Colon Rectum 52:711–714PubMedCrossRefGoogle Scholar
  39. 39.
    Bartram CI and Sultan AH (2007) Imaging of the anal sphincter. In: Sultan AH, Thakar R, Fenner D (eds) Perineal and anal sphincter trauma, diagnosis and clinical management, Springer, London, pp 123–132CrossRefGoogle Scholar
  40. 40.
    Bader FG, Bouchard R, Keller R et al (2008) Progress in diagnostics of anorectal disorders. Part I: anatomic background and clinical and neurologic procedures. Chirurg 79:401–409PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Italia 2012

Authors and Affiliations

  • A. Reginelli
    • 1
  • Y. Mandato
    • 1
  • C. Cavaliere
    • 1
  • N. L. Pizza
    • 1
  • A. Russo
    • 1
  • S. Cappabianca
    • 1
  • L. Brunese
    • 2
  • A. Rotondo
    • 1
  • R. Grassi
    • 1
  1. 1.Dipartimento di Internistica Clinica e Sperimentale “F. Magrassi e A. Lanzara”, Sezione di RadiodiagnosticaSeconda Università degli Studi di NapoliNapoliItaly
  2. 2.Dipartimento di Scienze della SaluteUniversità degli Studi del MoliseCampobassoItaly

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