Full thickness section from a resection specimen showing the absence of ganglion cells in both submucosal and myenteric plexuses in a case of short segment Hirschsprung disease. The presence of hypertrophic submucosal nerve fibers (seen on the left in this image) are an additional helpful feature in making the diagnosis. The presence of acetylcholinesterase positive cholinergic nerve fibers within the lamina propria (a feature not present in normal individuals) is additional supportive evidence for the diagnosis of Hirschsprung disease. Treatment of Hirschsprung Disease: The treatment is surgical and consists of resection of the aganglionic segment followed by anastomosis of normal proximal colon to the rectum. Intraoperative frozen sections are performed to confirm the presence of ganglion cells at the anastomosis.