ANORECTAL MALFORMATIONS.pdf PEDIATRIC CONGENITAL MALFORMATIONS

This presentation is about Anorectal Malformation.
No specific cause of anorectal malformation has been described.
The average incidence worldwide is 1 in 5000 live births.
Families have a genetic predisposition, with anorectal malformations being diagnosed in succeeding generations.
A slight male preponderance exists
Imperforate anus without fistula occurs in 5% of patients.
Interestingly, 50% of them also have Down syndrome
Patients with Down syndrome and anorectal malformations have this type of defect 95% of the time
Cardiovascular anomalies are present in approximately one third of patients but only 10% of these require treatment.
The most common lesions are: Atrial septal defect and patent ductus arteriosus followed by tetralogy of Fallot and ventricular septal defect

1. ANORECTAL MALFORMATIONS
DR SETH JOTHAM
LECTURER –DEPARTMENT OF SURGERY

2. OUTLINE
•Intro & embryo
•Epidemiology
•Classifications
•Associated anomalies
•Investigations & Findings
•Emergency rx
•Definitive rx

3. Introduction
Thecloacaintheembryoisacavityintowhichopensthehindgut,and
later,themesonephricducts.
Thecloacaisfirstformedataround21days’gestation
Inthis6-weekprocess,aurogenitalcavityanteriorlyandananorectal
cavityposteriorlyarecreated.

4. …
Thecloacalmembranebreaksdownat7weeks’gestation,thereby
creatingtwoopenings:
I.Theurogenitalopening
II.Theanalopenings.
Themusclesthatsurroundtherectumdevelopatthesametimeand
areseeninthesixthandseventhweeksofgestation,andbytheninth
week,allrelevantstructuresareinplace.
Atthisstage,differentiationintomaleorfemaleexternal
genitaliahasnotyetoccurred

5. From embryonic disc

6. Epidemiology
•Nospecificcauseofanorectalmalformationhasbeen
described.
•Theaverageincidenceworldwideis1in5000livebirths.
•Familieshaveageneticpredisposition,withanorectal
malformationsbeingdiagnosedinsucceedinggenerations.
•Aslightmalepreponderanceexists

7. Epidem Cont.…
•Themostcommondefectin
femalesisrectovestibular
fistula
•Themostcommondefectin
malesisrecto-urethral

8. Perineal fistula Vestibular fistula

9. Cloaca

10. NB:
•Imperforateanuswithoutfistulaoccursin5%ofpatients.
•Interestingly,50%ofthemalsohaveDownsyndrome
•PatientswithDownsyndromeandanorectalmalformations
havethistypeofdefect95%ofthetime.

11. Classification: Anatomically descriptive with therapeutic and prognostic implications.

12. Is it high or low?

13. .
ASSOCIATED ANOMALIES

14. 1. SPINAL, SACRAL, AND VERTEBRAL ANOMALIES
•Lumbosacralanomaliessuchas
lumber hemi-vertebrae,
scoliosis,hemi-sacrum/bifida
arecommon
.

15. .. The most frequent spinal problem is tethered
cord

16. 2. CARDIOVASCULAR ANOMALIES
•Cardiovascularanomaliesarepresentinapproximatelyone
thirdofpatientsbutonly10%oftheserequiretreatment.
•Themostcommonlesionsare:Atrialseptaldefectand
patentductusarteriosusfollowedbytetralogyofFallotand
ventricularseptaldefect.

17. 3. TRACHEOESOPHAGEAL ABNORMALITIES
(ATRESIA +/-FISTULLA)

18. .

19. .

20. .

21. .

22. I.E

23. 4. GENITOURINARY ANOMALIES
•Vesicouretericrefluxisthemostcommonanomalyfound.ButIn
othersetting;renalagenesisanddysplasiaarethemostfrequent
findings.
•Cryptorchidismisreportedinupto20%ofmaleswithimperforate
anushypospadiasoccursinapproximately5%.

24. 5. LIMB ANOMALIES
•Commonly lower limb and mostly presenting with clubbed foot.

25. Note: sacral ratio
•It’savaluableprognostictoolasitqualifiesthedegreeofsacralhypo-
development
•Patientswithratio<0.4areuniversallyincontinent
•Ratiosthatapproaches1usuallypredictsagoodprognosis

26. SR = AP view

27. SR= Lateral view

28. NB:
•Asacraldefect,particularlyhemisacrum,inassociationwith
imperforateanusandapresacralmassisknownastheCurrarino
triad.

29. I.E

30. Presentation
•Symptoms : Early sx of IO
•P/A : Signs of intestinal obstruction
PERINEALY: +/-Fistula and what is coming out , +/-bucket handle
deformity always indicating low malformation (see image below)

31. Bucket handle deformity

32. .

33. lateral cross table x-ray

34. Low or high? Consider <2cm or >2cm

35. .

36. .

37. What is the common definitive repair?
P-SARP

38. Which radiological investigation is essential
before P-SARP?
HIGHER DISTAL PRESSURE COLOSTOGRAM

39. .

40. RECTAL-VESSICAL

41. Which fistula?

42. What about this?

43. P-SARP

44. What follows after P-SARP?
SERIAL DILATATION

45. Which instrument is best used in dilatation?

46. ANS
HEGAR DILATOR

47. .

48. When to begin dilatation?

49. ANS

50. When should you go for colostomy closure?

51. ANS

52. After colostomy closure, should you stop dilatation?

53. ANS

54. QUESTION
As a surgical procedure, P-SARP is not without complications. Give a
brief account of the complications and their ideal management.
How to avoid those complications?

55. Note;
THE LOWER THE MALFORMATION, THE LOWER THE
COMPLICATIONS

56. .