What Is Anal Atresia?

Anal atresia is also known as anal lock, no anus. The disease is a common congenital gastrointestinal malformation, accounting for 1/1500 to 1/5000 of newborns, more men than women. Often combined with other deformities, accounting for about 41.6%. The etiology of this disease is unclear. After the baby is born, the anus, anal canal, and lower end of the rectum are closed. The appearance of the anus cannot be seen. Clinically, it is mainly surgical treatment.

Basic Information

nickname

Anal lock, no anus

English name

imperforate anus,

Visiting department

Pediatric Surgery, General Surgery

Multiple groups

Newborn

Common locations

anus

Common causes

unknown

Common symptoms

No meconium excretion, vomiting, abdominal distension and other symptoms of gastrointestinal obstruction

Contagious

no

Causes of anal atresia

Due to the primary anal developmental disorder, the anal canal was not recessed inward. Rectal development is basically normal, with its blind end at the edge of the urethral bulb sponge muscle, or near the lower end of the vagina, and the pubic rectum muscles surrounding the distal rectum. The perineum is often stunted and flat, and the anal area is covered by intact skin. Can be combined with urethral bulb, lower vagina or vestibular fistula.

Clinical manifestations of anal atresia

The patient had no meconium excretion after birth, and symptoms of gastrointestinal obstruction such as vomiting and bloating soon appeared. After a local examination, the center of the perineum was flat and the anal area was covered with skin. In some cases, there is a small depression with obvious pigmentation and radiation wrinkles, which can stimulate the contraction of the ring muscles. When the baby is crying or holding his breath, there is a protrusion in the center of the perineum. Fingers placed in this area can have a sense of shock. The baby is placed on the hips with the head down and the anus in the anus as a drum sound.

Diagnosis of anal atresia

There was no meconium excretion after birth, the anal area was covered with skin, and the anal area felt a shock when crying. On the inverted X-ray lateral film, the end of the rectum is located at or slightly below the pubic tail line, and the blind end of the rectum was measured about 1.5 cm from the skin of the anal area by ultrasound and puncture.

Anal atresia treatment

Surgical treatment should be performed as soon as possible after diagnosis. Perineoplasty is generally performed, and perineoplasty can also be used.

Incision

Make an X-shaped incision in the center of the perineum or in the middle of the ring-shaped contractile area, which is about 1.5 cm long. The skin was incised, and 4 flaps were opened, with circular external sphincter fibers visible below it.

2. Look for free rectal blind ends

Use ant-type vascular forceps to bluntly separate the soft tissue through the middle of the sphincter to find the blue rectal blind end. Two thick silk threads are threaded through the blind end muscular layer for traction. The blind rectum is located inside the puborectalis muscle ring, so it should be separated close to the intestinal wall. The free blind end is about 3cm, so that the rectum can be pulled loosely to the anus. The free rectum must have sufficient length. If the rectum is not sufficiently free and the suture is reluctantly pulled, the intestinal wall retracts very easily after operation, causing scar stenosis. Damage to the urethra, vagina and rectum should also be avoided during separation.

3. Cut the rectum

Make a cross-shaped incision at the blind end of the rectum, and suck up the meconium with an aspirator, or let it flow out and wipe. Pay attention to protect the wound and avoid pollution as much as possible. If contamination occurs, it should be carefully rinsed with normal saline.

4. Anastomosis and fixation

The blind end of the rectum and the surrounding soft tissue were fixed with a few needles, and the intestinal wall and the perianal skin were intermittently sutured with a filament or intestine. Note that the intestinal wall and the skin flap should cross and align, so that the scar is not on a flat surface after healing. Anal expansion began around 10 days after surgery to prevent anal stenosis.