This document discusses anorectal malformation (ARM), a birth defect where the anus is abnormally formed or missing. It begins by defining ARM and describing associated fistula tracts. It then covers the embryological theories of development. The document details symptoms, examination findings, and classification systems. Treatment options like surgical correction through primary repair or staged repair are outlined. Post-operative complications are also addressed. The goal of surgery is to create a functional anus and avoid issues like incontinence.

1. ANORECTAL MALFORMATION
Dr Reshma Chandrasekaran
DNB General Surgery Resident

2. INTRODUCTION
• Anorectal malformation is the general term for a variety of diagnoses
often referred to as imperforate anus.
• Patients with this diagnosis do not have a normal anal opening, but
instead, a fistulous tract opens onto the perineum anterior to the anal
muscle complex or into adjacent anatomical structures.
• In the male, the fistulous tract can connect to the urinary system and in
a female, to the gynecologic structures.

3. EMBRYOLOGY
• THEORY 1: Embryonically the urinary tract, reproductive tract, and
gastrointestinal tract form a common channel called a cloaca, which is
followed by separation of these structures and the migration of the
anorectal septum around the seventh week of gestation.
• THEORY 2: The rectum migrates towards the perineum during
development, and this is abnormal in the formation of anorectal
malformations.

4. ANATOMY OF RECTUM AND ANALCANAL

8. SYMPTOMS / SIGNS
• No visible anus or an anal opening that is not in the normal location
• Inability to pass stool or constipation
• Stool that leaks from the vagina or is visible in the urine
• Urine that comes from the anus
• An anus that is tighter or more narrow than normal

10. EXAMINATION
• For an anus to be normal, it should be in the correct location and the proper size, based on
age.
• The normal size anus of a full-term infant is a 10 to 12 Hegar dilator (an instrument used to
size the anus), and the size of a 12-month-old should be about a 15 Hegar dilator.
• The basis of the correct location is on the anal opening being in the center of the anal muscle
complex.
• The perineum should be thoroughly evaluated taking care to pay attention to features such as
the development of the buttocks, the presence of a gluteal fold, and the examination for any
type of opening or orifice on the perineum.
• In female patients with an anorectal malformation, a thorough vaginal exam should also take
place, taking care to note the number of openings on the perineum.

21. Less than 0.5 indicates poor continence post
op.

30. TREATMENT OF LOW LYING ARM
OperOperative procedure for the surgical treatment of anal stenosis. A: Martin’s anoplasty; B: Y-V
advancement flap;
C: V-Y advancement flap; D: Diamond-shaped flap; E: House-shaped flap; F: U-shaped flap; G: Rotational S-
flap.

31. GOALS OF SURGERY
• The most important aim of the surgical correction is
to create a normal anus with anatomic
reconstruction.
• Surgery should help the child to achieve a socially
acceptable bowel function and should ensure
avoiding fecal incontinence, urinary incontinence or
sexual dysfunction.
• The choices of surgical correction are as follows:
• a. Primary repair – both boys and girls (3-6)
• b. Staged repair – usually 3 stages:

32. STAGED REPAIR
• i. Colostomy – most probably high sigmoid loop in left iliac fossa.
• ii. Pull through – Posterior sagittal approach, abdomino-perineal
approach, abdominal posterior sagittal approach, laparoscopic
approach – in boys; anterior sagittal approach, anal transposition,
posterior sagittal, abdomino-perineal, abdominal posterior sagital
approach – in girls.
( regular dilatation of new anus after 3 weeks)
• iii. Colostomy closure. (after 3 months)

34. INDICATION FOR COLOSTOMY

37. DISTAL COLOSTOGRAM
• Water-soluble contrast is used and continued pressure is applied during
injection of dye to ensure that the fistula is opacified.
• Images are obtained under fluoroscopy.
• The colostogram is obtained in the lateral position, with the femora
overlapping as perfectly as possible, to determine the level of the blind
end of the rectum and identify the type of ARM.

41. STEPS
• Step 1: Placing sutures around fistula
• Step 2: Sagittal opening in midline
• Step 3: Dissection fistula/ rectum
• Step 4: Reconstruction of sphincter complex
• Step 5: Anoplasty

45. LAARP
• Laparoscopically assisted anorectal pull-through (LAARP) for high
anorectal malformations (ARMs) reduces the amount of posterior
dissection and avoids dividing and weakening external sphincters
required for accurate placement of the bowel into the muscle complex
and diminishes perirectal scarring.
• Repair of associated defects at operation (i.e., hernia, identification and
repair of cryptorchid testes) is possible.

46. (a) Slingshot appearance of puborectalis. (b) Laparoscopic backlight
as a guide for perineal incision.
(c) 10 mm trocar inserted into the peritoneal cavity.
(d) Rectal pull-through through 10 mm trocar
(a) Port placement. (b) Visualization of anatomy. (c)
Subserosal dissection. (d) Creation of tunnel through the
puborectalis

47. POST OP COMPLICATION
• Post-operative complications can include:
1. Superficial and deep wound infection,
2. Dehiscence of the anastomosis,
3. Prolapse of the anoplasty, or stricture of the anoplasty.
• Recurrent fistulas between the urinary system in males or
gynecologic system in females can also occur.
• These usually occur if the surgical repair is on excessive tension
or there is inadequate blood supply to the rectum.

49. Peristeen empties the bowel by introducing water into the bowel using a rectal catheter.

50. Following MACE surgery, the bowel is “flushed” , usually daily, with body
temperature water through a catheter inserted into the bowel through the stoma.
Each irrigation generally takes 30-60 minutes

51. CONCLUSION
• Multidisciplinary approach: paediatrician, paediatric surgeon,
radiologists, nursing team, physiotherapist, and stoma care nurse etc.
• Pre operative workup
• Meticulous surgical technique
• Post op follow-up

52. THANK YOU