Idiopathic myointimal hyperplasia of
mesenteric vein

CT shows severe edematous wall thickening
of rectosigmoid colon, obliterated pericolic and IMV with venous collaterals.

REVIEW

Very rare cause of sigmoid and rectal
colitis

First report in 1991

Average age : 52( 22-81), Male predominance

Rectosigmoid colon in most commonly
affected.

Often misdiagnosed as IBD initially.

Only diagnosed after pathologic review

-      
Nonthrombotic , noninflammatory
occlusion of mesenteric veins secondary to intimal smooth muscle hyperplasia

Pathogenesis

-      
acquired segmental AV fistula

-      
Increased pressure in venules,
arteriolization, and hyperplasia of the vessel wall

-      
Luminal narrowing of mesenteric
veins

-      
Varable recanalization followed
by ischemia and bowel necrosis

Clinical manifestation

-      
Segmental involvement of
rectosigmoid colon

-      
Abdominal pain, rectal
bleeding, diarrhea

Treatment  : complete surgical
resection

         -No known medical
treatment, but uneventful follow-up without recurrence after surgery

Radiological findings

-      
Involvement of distal rectum

-      
No visualization of IMF at the
left renal vein level

-      
Complete occlusion of IMV
without thrombosis and vasculitis

-      
Venous stasis and aneurysmal
change

-      
Patent IMA

Reference