Annular Pancreas

00:01 Welcome. In this lecture, we're going to discuss the annular pancreas.

00:07 So, just what it sounds like, it's a ring of pancreatic tissue encasing the first part of the intestine.

00:12 That is to say at the duodenum.

00:15 The epidemiology of this is that it is relatively uncommon, about 5-15 per 100,000 adults and it is a developmental anomaly.

00:25 It's commonly associated with a variety of other GI tract anomalies such as a Meckel's diverticulum or an imperforate anus.

00:33 It can be causal for duodenal atresia or secondary as a primary aspect of duodenal atresia.

00:40 It can be due to esophageal atresia. It's also associated with Down syndrome.

00:46 And because we do not have normal movement of ingested material from esophagus to rectum, there may be an excess accumulation of fluid within the amniotic sac so there may be polyhydramnios, so a number of concomitant abnormalities.

01:04 In terms of the pathophysiology, we have to understand how the normal pancreas forms, it sits there with the head at the loop of the duodenum.

01:14 And instead of forming a nice organ that leads off into the left lateral space behind the stomach, it encircles the duodenum.

01:25 So in normal development, we have a ventral bud of the pancreas that sits anterior, a dorsal bud that sits posterior, and normally that ventral bud will either migrate posteriorly or anteriorly to fuse and make the final pancreatic body.

01:46 If that doesn't happen, if we don't get the normal migration of the ventral bud, it can actually end up encircling completely around the duodenum and then fuse with the dorsal bud leaving a circle of tissue.

02:02 That annular pancreas then is going to present in neonatal life with abdominal distention and pain with vomiting because we cannot empty the stomach due to the encircling amount of tissue.

02:17 How do we make the diagnosis? Ultrasound can do it but an upper GI series such as is shown here is probably going to be the best and you can see that the stomach it fills quite nicely, and then we get down to the pylorus and we have this very narrowed segment of the duodenum and that's narrowed by having that encircling annular pancreas.

02:39 CT can also demonstrate this.

02:43 For management, there is really only one thing to do and that is to open up and dilate the duodenum so that you get normal flow.

02:52 So duodenoduodenostomy and say that 3 times really fast if you can. With that, annular pancreas.