Colorectal Quiz: Episode 44 - HD Frozen Section

Late-onset Hirschsprung patients tend to present with more subtle symptoms, more constipation, and fewer issues with enterocolitis compared to neonatal presentations.

Frozen section pathology for Hirschsprung can be misleading; marking biopsy sites with prolene stitches and obtaining permanent pathology before pull-through is preferable.

If biopsy sites are not marked, it is very hard to find them in the future.

The laparoscopic approach allows preservation of the colonic arcade and the inferior mesenteric artery without overstretching the anus, resulting in a well-perfused, tension-free pull-through.

The laparoscopic portion of Hirschsprung pull-through minimizes the amount of anal stretch required and is very precise and elegant.

In older children with Hirschsprung where the transition zone level is confirmed, transanal-only approach may be considered because you know exactly where the transition zone is and can reach it.

A disadvantage of taking biopsies at the time of ileostomy creation is that adhesions often form between former biopsy sites and the lateral abdominal wall.

The anastomotic donut should be divided into four quadrants to ensure ganglion cells are present circumferentially, because the transition zone is sometimes like a lip and not circumferential.

The commonly stated rule to go 5 centimeters above the transition zone is actually not true; there is often a longer transition zone in many cases.

There are advantages to having the ultimate pull-through nice and straight (usually upper sigmoid) if you ever need to irrigate.

It is very important to send a full-thickness biopsy cube, not a diamond; the seromuscular layer square needs to be the same size as the mucosa square to prevent errors from tangential cutting if the specimen is not oriented correctly.

Ganglion cell distribution should be visualized like a paint can with ganglion cells dripping down the sides, not as concentric circles; you could theoretically biopsy in a transition zone where there is only a drip of paint, not where the paint is absent.

Pathologists doing Hirschsprung biopsies correctly will refuse to do analysis unless you give them submucosa, because checking seromuscular layer only is a cardinal sin.

The pathologist must confirm that not only is the seromuscular layer good, but the submucosal layer is also good, because seromuscular could have ganglion cells while submucosal layer could have hypertrophic nerves.

The results of reoperative transanal Hirschsprung pull-throughs are not great, with a high number of anastomotic dehiscences, partly because you can never enter the anal canal in the same plane during a redo.

If you go back early after initial pull-through, you can release the stitches and arrive in the same plane again, allowing re-anastomosis to the anal canal exactly in the same plane as the initial surgery, which is why early re-operation avoids dehiscence.

Reoperative transanal Hirschsprung surgery is not as complicated if you go back early.