Colorectal Quiz Episode 1 - Low Bulbar Fistua

VACTERL workup for anorectal malformation includes vertebral abnormalities (plain X-ray), cardiac defects (exam and echo), esophageal atresia (NG tube passage), renal abnormalities (kidney ultrasound), and limb abnormalities (physical exam).

True sacral ratio measurements should wait until the child is 3 months of age, though early imaging gives a sense of pelvic development.

Spinal ultrasound should include evaluation of the presacral space to look for presacral masses.

In anal stenosis or rectal atresia defects, presacral masses are found almost half the time, and those patients require MRI.

Cross-table lateral X-ray should be obtained at approximately 24 hours of life to assess the air column position relative to the perineal skin.

Cross-table lateral is performed with the baby prone, positioning the buttock at the highest point where air will rise.

Cross-table lateral can be obtained at bedside in the neonatal unit by placing the baby on a bump under the buttocks.

A marker should be placed where the anus is thought to be appropriate on the cross-table lateral to allow measurements and inform operative approach.

A sacral ratio greater than 0.7 connotes very good prognosis for bowel control.

Well-formed buttocks, visible sphincter mechanism location, and well-developed sacrum together indicate likely good prognosis for continence.

The key to deciding whether to perform posterior sagittal anorectoplasty is knowing where the rectum is located.

The danger of blind posterior sagittal approach is finding a midline white structure like the urethra, bladder neck, or bladder itself instead of the rectum.

Colostomies and distal colostograms are performed to know exactly where the rectum is and whether to approach it perineally or laparoscopically.

Colostomy is the safe choice for anorectal malformation repair, though it carries risks of complications from both the colostomy creation and the subsequent closure.

If primary anorectoplasty is performed without recognizing a fistula, the child may later urinate through the anus.

During primary posterior sagittal repair, the posterior wall of the rectum should be opened and the anterior wall inspected to rule out fistula.

When a fistula is very close to the rectum, it is important to identify the proper dissection plane between the two structures.

A bulbar fistula is located at the elbow of the urethra, using anatomic nomenclature.

Distal colostogram should still be performed in Down syndrome patients with imperforate anus because some may have a fistula despite the lower prevalence.

95% of patients with Down syndrome and imperforate anus have no fistula, but 5% do have a fistula.