CT air-contrast enema as a preoperative examination for colorectal cancer.
OBJECTIVE
We conducted a study on three-dimensional computed tomography (CT) images, in particular CT air-contrast enema (CT enema), using multidetector-row CT (MDCT), to see whether CT enema is useful as a preoperative examination for colorectal cancer. We aimed to evaluate the detectability of lesions and the depth of cancer invasion using CT enema.


METHODS
292 patients (328 lesions) with colorectal cancer were enrolled. After an adequate insufflation of the large intestine, MDCT scans were performed. With the data obtained by MDCT, we reconstructed CT enema images. CT enema images were assessed for the detectability of lesions. The depth of invasion was evaluated by the deformity of the lesion on profile images. The deformities were divided into five groups: no deformity, slight deformity, mild deformity, moderate deformity and severe deformity.


RESULTS
The detectability of lesions was 97.3%. The reasons for undetectability were due to residual fluid in 8 cases and insufficient colonic distention in 1 case. As the depth of invasion increased, the grade of the deformity became severer (p < 0.0001).


CONCLUSIONS
CT enema proved to be an excellent examination tool to detect lesions. The deformity demonstrated by CT enema could be an additional source of information to predict the depth of invasion.
Nagata
Koichi
K
Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Japan. Nagata7@aol.com
Endo
Shungo
S
Kudo
Shin-ei
SE
Kitanosono
Takashi
T
Kushihashi
Tamio
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000388:Air; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003287:Contrast Media; D004733:Enema / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D014057:Tomography, X-Ray Computed
D003287:Contrast Media