Trisomy 21

Etiology: Congenital
Imaging:
DDX:
Complications:
— Moya Moya syndrome
— Occiput-C1, C1-C2 instability
— Peripheral lung cysts
— Atrioventricular canal defect, atrial septal defect, ventricular septal defect
— Duodenal atresia
— Annular pancreas
— Hirschprung disease
— Trident hand
— Increased risk of leukemia
Treatment:
Clinical:

Radiology Cases of Atlanto Axial Instability in Trisomy 21

Radiograph of atlanto axial instability — Lateral radiographs of the cervical spine show a mildly enlarged atlanto dens interval in neutral position (left), that increases significantly on flexion (center) and reduces on extension (right).

Radiology Cases of Atlanto Occipital Instability in Trisomy 21

Radiograph of atlanto occipital instability — Lateral radiograph of the cervical spine in flexion (left) shows a normal atlanto dens interval and normal relationship of the occipital condyles to the lateral masses of C1 while on extension (right) there is posterior translation of the occipital condyles in relation to the lateral masses of C1.

Radiograph of atlanto occipital instability — Lateral flexion view of the cervical spine (left) shows a normal relationship of the occipital condyles to the articular facets of the atlas. The atlanto dental interval is also normal. Lateral extension view of the cervical spine (right) shows posterior displacement of the occipital condyles in relation to the articular facets of the atlas. There is posterior positioning of Wackenheim line and retrolisthesis of the C3 on C4 vertebral body. The atlanto dental interval remains normal.

Radiology Cases of Duodenal Atresia in Trisomy 21

UGI of duodenal atresia — AP (above) and lateral (below) images from an UGI exam show a dilated stomach and first part of the duodenum. On a delayed image obtained 15 minutes later, no contrast was seen to have passed out of the duodenum into the remainder of the bowel.

Radiology Cases of Duodenal Stenosis in Trisomy 21

AXR and UGI of duodenal stenosis — AXR (above) shows the tip of the nasogastric tube within a very dilated duodenal bulb. There is extensive distal bowel gas. Spot image from an upper GI (below) shows a fixed area of narrowing between the first and second portions of the duodenum through which contrast passed slowly.

Surgical Cases of Trisomy 21 with Duodenal Atresia

Surgical image of duodenal atresia — Surgical image shows the dilated first part of the duodenum in the center of the image and the normal caliber second part of the duodenum being held between the forceps. There was a 5 cm gap between the first and second parts of the duodenum.