MDCT finds cause of acute abdomen more often with MPR By Eric Barnes AuntMinnie.com staff writer November 29, 2006
CHICAGO - The use of multiplanar reconstructions (MPRs) can help identify the site, level, and cause of acute abdominal diseases when transverse multidetector-row (MDCT) findings are indeterminate, according to researchers from Beijing, China.
Dr. Degui Zu from Metian General Hospital presented a study of 128 acute abdominal patients on Tuesday at the 2006 RSNA meeting. The group sought to "determine the benefit of multiplanar reformatted images of the abdomen and pelvis … by comparing the use of MPR images and single transverse images," Zu said.
The radiologists examined 128 consecutive patients with clinically suspected acute abdomen who underwent CT of the entire abdomen and pelvis on a LightSpeed VCT 64-slice scanner (GE Healthcare, Chalfont St. Giles, U.K.).
Axial, sagittal, coronal, and oblique MPR images were created on an Advantage 3D workstation (GE). Two experienced abdominal radiologists reviewed images together. Statistical analysis was performed by using the paired t-test and the Spearman correlation coefficient, Zu said.
In all, the two readers diagnosed 59 of the 128 patients (46.1%) with acute abdominal diseases, including acute appendicitis (n = 16), bowel obstruction (n = 21), acute pancreatitis (n = 5), epiploic appendagitis and adnexal tumor (n = 3), colon diverticulitis (n = 2), aortic aneurysm (n = 2), cholecystolithiasis (n = 6), and stone of urinary system (n = 4).
Using transverse images alone, the two readers diagnosed acute abdominal diseases with 85.3% sensitivity and 92.4% specificity. With the aid of MPR, sensitivity was 89.6% and specificity was 97.8%.
"For six of 59 patients, 10.7%, the disease can only be detected with MPR, while single transverse findings were indeterminate," Zu said.
Isotropic scanning provides excellent image quality in any plane, and the use of MPR images provides excellent anatomic delineation. The use of MPRs "may help identify the site, level, and cause of various kinds of acute abdomen diseases when transverse CT findings are indeterminate," Zu said. "It may improve the ability to make an early and accurate diagnosis for abdominal patients, and provide optimal treatment planning."
In one example, coronal and sagittal contrast-enhanced CT showed three sections (inner intestine, middle vaginal bowel wall, and outer colonic wall) in the locus of intussusception, and a small intestinal mesentary tucked into the colonic lumen was seen corresponding to invaginated ileac bowel, Zu explained. The proximal bowels of the obstruction were distended. Maximum intensity projection (MIP) image showed a mesenteric ileocolic vessel and middle colic vessels tucked into the ascending colon.
By Eric Barnes
AuntMinnie.com staff writer
November 29, 2006