A 79-year-old man
was referred for CT colonoscopy (CTC) following optical
colonoscopy. Unusually, the request was not due to an incomplete
optical colonoscopy. The patient was referred because the
gastroenterologist had identified a large polyp for resection but
was unable to identify its exact location and secure it for
resection during the optical procedure.
Findings
The first CT colonoscopy image shows a
1.66-cm polyp (2b) in the ascending colon, approximately 203 cm
from the rectum. Note also intestinal malrotation, with the small
bowel occupying the right abdomen and the colon occupying the left
abdomen. As a result, the cecum has a midline position.
The second CT colonoscopy image shows an
additional 0.5 cm-polyp in the sigmoid colon.
Discussion
The patient was
scanned using low-dose protocol on a 64-slice CT in both the prone
and supine positions. The CT images immediately revealed the reason
behind the difficulties experienced by the gastroenterologist. The
patient exhibited intestinal malrotation, with the small bowel
located in the right abdomen and the colon located in the left
abdomen. If this condition has not been previously identified in a
patient, it is impossible for the gastroenterologist to recognize
it during an optical procedure.
Using CTC, we
were able to demonstrate the exact size and location of the polyp
(Figure 1) to the gastroenterological surgeon. The global view
together with the 3D virtual endoscopy, with automatic size
measurement, proved convincing tools for communication with our
surgical colleagues. Additionally, we were able to identify another
smaller lesion in the sigmoid colon which had not been identified
in the optical examination (Figure 2).
This case clearly
demonstrates the clinical benefit of "X-ray vision" for difficult
anatomical cases. CTC gave us a clear picture of the entire anatomy
and, using CT colonography, we were able to
confidently guide the surgeons to a successful clinical
outcome.