Congenital absence of anal opening can happen both in male and female babies. Since they can't pass stool, this is a neonatal emergency surgical problem. Exact type of anomaly should be ascertained and appropriate surgical correction should be done precisely.

1. ANORECTAL AANNOOMMAALLIIEESS
((IIMMPPEERRFFOORRAATTEE AANNUUSS))

2. ANORECTAL ANOMALIES
Dr.B.SELVARAJ MS;Mch; FICS;
ASSOCIATE PROFESSOR IN PEDIATRIC SURGERY
MELAKA MANIPAL MEDICAL COLLEGE
MELAKA 75150 MALAYSIA
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3. ANORECTAL ANOMALIES
Able to identify associated anomalies
Appropriate workup to confirm the type of anomaly
Objectives
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Identify anomalies in male && ffeemmaallee bbaabbiieess
PPllaannnniinngg ooff ssuurrggiiccaall ttrreeaattmmeenntt ffoorr ddiiffffeerreenntt ttyyppeess
PPrrooppeerr ppoossttoopp ccaarree && ffoolllloowwuupp
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4. ANORECTAL ANOMALIES-Embryology
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•Cloaca formed at 21 days with
Allantois joining anteriorly & hindgut
joining posteriorly
•Urorectal septum divides cloaca into
anterior urogenital cavity & posterior
rectoanal cavity
•Urorectal septum touches cloacal
membrane & divides it into anterior
urogenital membrane & posterior anal
membrane
• Ultimately these membranes breakdown
producing anterior urogenital& posterior
anal openings

5. ANORECTAL ANOMALIES-Embryology
Rectoanal atresias & fistulas occur 1/5000 livebirths due to
defective cloacal formation
Decrease in size of posterior portion of cloaca & shortening of
cloacal membrane results in ectopic anal opening into urogenital
sinus
Depending on the size of posterior portion of cloaca the
rectourethral fistula may be high or low
Defect is due to ectopic positioning of anal opening & not in any
defect in urorectal septum
Imperforate anus: The anal canal fails to recanalise, leaving a
diaphragm between the upper & lower portions of the anal canal
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6. Classification of Anorectal Anomalies
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7. Classification of Anorectal Anomalies
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8. ANORECTAL ANOMALIES
Develop during first 2 months of life- but cause is unclear
Agents causing the anomaly have general noxious effects on
the developing fetus- hence associated anomalies are common
Males are more affected with severe malformation
Incidence 1 in 5000 livebirths
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9. ANORECTAL ANOMALIES
Present as absence of anus in it’s normal position
In mild forms bowel outlet opens in perineum outside the well
developed muscle sphincter complex
In severe forms bowel outlet opens in urogenital tract in males
& genital tract in females
Neonatal recoginition of type of anomaly is essential for
planning the surgical management
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10. MALE ANORECTAL ANOMALIES
Perineal Fistula
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C Associated with a median bar
Opens also on either side of
median bar(covered anus)
Opens along or tip of median
bar/ stenotic opening
Opens in midline perineal
raphae, scrotum or base of
penis

11. MALE ANORECTAL ANOMALIES
Rectobulbar fistula
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Rectum opens into the bulbar
urethra
Presence of anal pit in
perineum
Long common wall of rectum
and urethra
Voluntary sphincter muscle
complex is well developed

12. MALE ANORECTAL ANOMALIES
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Rectoprostatic urethral fistula
C Rectum opens into prostatic
urethra
Passing meconium through
urethra
Sacral deformity is more
severe than in bulbar fistula
Flat perineum with hypoplastic
voluntary sphincter muscles

13. MALE ANORECTAL ANOMALIES
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Recto vesical fistula
Rectum opens into urinary bladder
Relatively uncommon; no common wall
between rectum and bladder
Flat perineum with hypoplastic voluntary
sphincter muscles
S evere Sacral deformity

14. MALE ANORECTAL ANOMALIES
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Anorectal Anomaly with no fistula
Rectum ends blindly behind the urethra
Blind end usually extends to a well
formed anal pit
Presence of well developed voluntary
sphincter muscle complex
T ypical presentation in a Down’s
syndrome

15. MALE ANORECTAL ANOMALIES
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Rectal Atresia(same in male & female)
Normal looking anal opening ending
just above dentate line
Proximal blind ending rectum is very
much dilated
Voluntary sphincter muscle complex is
well developed
L ocal vascular abnormality is the cause

16. FEMALE ANORECTAL ANOMALIES
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Perineal Fistula(Anterior Ectopic Anus)
Moderately stenotic anus situated
anteriorly right behind vestibule
Fistula opening more anterior than in
males
Voluntary sphincter muscle complex is
well developed except anteriorly
Perineal groove between fistula and
v estibule

17. FEMALE ANORECTAL ANOMALIES
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Rectovestibular Fistula
Fistula in posterior fourchette of
vestibule behind hymenal ring
Anterior rectum and posterior vagina join
& forms common wall for 2-4 cms
Voluntary sphincter muscle complex is
well developed
Vaginal anomalies are common

18. FEMALE ANORECTAL ANOMALIES
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Cloacal Anomaly with < 3 cms common channel
Urinary tract, vagina and rectum join in
a common channel
The orientation and anatomy of cloaca
are extremely variable
Urinary tract abnormalities like obstructive
uropathy is common
Vaginal & uterine duplications with
Neonatal Hydrocolpos occur in 50%

19. FEMALE ANORECTAL ANOMALIES
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Cloacal Anomaly with > 3 cms common channel
Babies with long channel tend to have
poor sphincter
Agenesis of Mullerian structures is not
uncommon
Severe sacral anomalies

20. FEMALE ANORECTAL ANOMALIES
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Anorectal Anomaly with no fistula
Uncommon in females
Most babies have Down’s syndrome
Short distance between blind ending rectum and well
formed anal pit
Well-developed sphincters

21. ANORECTAL ANOMALIES
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Associated Anomalies

22. ANORECTAL ANOMALIES- Preop workup
Clinical examination discloses the type of anomaly in majority
of cases
Cross-table lateral plain xray in doubtful cases to be done
after 18-24 hrs
Early perineal USG to confirm type of anomaly
Abdominal USG& Echo to R/O associated anomalies
CT & MRI to reveal integrity of sphincter muscles
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23. ANORECTAL ANOMALIES- Preop workup
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Cross-table lateral radiograph

24. ANORECTAL ANOMALIES- Preop workup
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Cross-table lateral radiograph
Low anomaly
Intermediate Anomaly
High anomaly

25. ANORECTAL ANOMALIES- Surgeries
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26. Newborn male with anorectal malformation
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27. Newborn Female with anorectal malformation
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28. Anoplasty for low anomaly in Male
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29. Anterior Ectopic Anus- Posterior
Transposition
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30. Proximal Sigmoid Colostomy
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Split Colostomy in proximal
s ig m oid colon
Washout of distal blind ending
bowel is easier
Risk for prolapse is less

31. Distal Colostogram
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Pressure distal colostogram
revealing the fistula
Dye fillsup both bladder and
urethra

32. Posterior Saggital Anorectoplasty
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Baby in prone position
Midline Saggital incision

33. Posterior Saggital Anorectoplasty
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O p e ning Rectum
Identifying Fistula
Separating Fistula

34. Posterior Saggital Anorectoplasty
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Mobilising rectum
away from fistula
Closing Fistula
Mobilising rectum
for tappering

35. Posterior Saggital Anorectoplasty
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Closing muscle
complex
Closing Sphincter
Closing skin

36. Posterior Saggital
Anorectovaginourethroplasty
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Posterior midline
incision
Opening common
channel
Identifying vagina
rectum & urethra

37. Posterior Saggital
Anorectovaginourethroplasty
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Separating rectum
from vagina
Separating vagina
from urethra
Tubularising
common channel

38. Posterior Saggital
Anorectovaginourethroplasty
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39. Total Urogenital Mobilisation
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Cloacal anomaly
Separating rectum from
vagina & urethra
Separating urogenital
sinus

40. Total Urogenital Mobilisation
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Total urogenital
mobilisation
Mobilising rectum from
urogenital sinus
Skin closure

41. Total Urogenital Mobilisation
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42. Assessment of functional outcome
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43. Assessment of functional outcome
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