Preoperative detection of hepatic metastases: comparison of diffusion-weighted, T2-weighted fast spin echo and gadolinium-enhanced MR imaging using surgical and histopathologic findings as standard of reference.

PURPOSE: The purpose of this study was to retrospectively compare the respective sensitivities of diffusion-weighted (DW), T2-weighted fast spin-echo (T2WFSE) and gadolinium chelate-enhanced MR imaging in the preoperative detection of hepatic metastases using intraoperative ultrasonographic and histopathologic findings as the standard of reference. MATERIALS AND METHODS: Twenty-seven patients with 64 surgically and histopathologically proven hepatic metastases had MR imaging of the liver, including DW, T2WFSE and dynamic gadolinium chelate-enhanced MR imaging. Images from each MR sequence were separately analyzed by two readers with disagreements resolved by consensus readings. The findings on MR images were compared with intraoperative ultrasonographic and histopathologic findings on a lesion-by-lesion basis to determine the sensitivity of each MR sequence. Statistical review of the lesion-by-lesion analysis was performed with the McNemar test. RESULTS: DW, T2WFSE and gadolinium chelate-enhanced MR imaging allowed the depiction of 54/64 (84.4%; 95% CI: 73.1-92.2%), 44/64 (68.8%; 95% CI: 55.9-79.8%), and 51/64 (79.7%; 95% CI: 67.8-88.7%) hepatic metastases respectively. DW MR images allowed depiction of significantly more hepatic metastases than did T2WFSE and was equivalent to gadolinium chelate-enhanced MR imaging (P=.002 and P=.375, respectively). CONCLUSION: DW MR imaging is superior to T2WFSE imaging and equivalent to gadolinium chelate-enhanced MR imaging for the preoperative detection of hepatic metastases. Further studies however are needed to determine at what extent DW MR imaging can be used as an alternative to gadolinium chelate-enhanced MR imaging for the preoperative depiction of hepatic metastases.

Crohn's disease: multi-detector row CT-enteroclysis appearance of the appendix.

The objective of our retrospective study was to determine the MDCT-enteroclysis appearance of the appendix in patients with Crohn's disease and to correlate this appearance with the status of the disease. We reviewed the MDCT-enteroclysis examinations of 76 patients with Crohn's disease. Images were analyzed for visualization of the appendix, largest axial diameter of the appendix and degrees of enhancement. Findings were correlated with the status of the disease (active vs. nonactive) and compared with those observed in a control group. Among the various variables, hyperenhancement of the appendiceal wall was found in 18.9% of patients with active disease and in no patients with inactive disease nor in the control group (P = 0.0023). This sign had a specificity of 100% for differentiating between active and inactive Crohn's disease. We conclude that increased appendiceal wall enhancement is, at a statistically significant level, more frequently observed in patients with active Crohn's disease by comparison with patients with inactive disease and control subjects. This result suggests that this finding may be used as an additional MDCT-enteroclysis finding to determine the activity of the disease.

Abdominopelvic extra-enteric findings at computed tomography enteroclysis: a retrospective evaluation of 430 consecutive patients.

BACKGROUND: Our objective was to retrospectively determine the frequency with which CT enteroclysis (CTE) shows abdominopelvic extra-enteric abnormalities and to analyze how such findings had actually and prospectively affected patient's care. METHODS: The CTE examinations of 430 consecutive patients were retrospectively and blindly reviewed for the presence of possible pathologic conditions that might have affected abdominopelvic organs other than the small bowel. Extra-enteric abnormalities were categorized as negligible or important and correlated with patient's outcome and thus classified as having or not influenced patient's care. RESULTS: Abdominopelvic extra-enteric abnormalities were present on CTE in 258 (60%) of 430 patients. Retrospective analysis of CTE images revealed negligible abnormalities in 217 patients (217/430, 50.5%) and important ones in 41 patients (41/430, 9.5%). Among the 41 patients with important abnormalities, CTE demonstrated already documented abnormalities in 22 patients (22/41, 53.7%) and unknown abnormalities in 19 patients (19/41, 46.3%). In the latter 19 patients, the detection of unknown abnormalities altered patient's care in 18 (94.7%) of them. In one patient (1/19, 5.3%), important abnormality was detected during retrospective evaluation but not prospectively, resulting in a delayed treatment, yielding missed important abnormality rate of 2.4% (1/41). CONCLUSIONS: Abdominopelvic extra-enteric abnormalities are frequent on CTE, but their depictions rarely alter patient's care. However, in a few patients (19/430; 4.4%), CTE may reveal unknown extra-enteric abnormalities that require further evaluation and have substantial impact on patient's management.

Capsule endoscopy or push enteroscopy for first-line exploration of obscure gastrointestinal bleeding?

BACKGROUND AND AIMS: The position of capsule endoscopy (CE) relative to push enteroscopy (PE) in the diagnostic algorithm of obscure gastrointestinal bleeding is unclear, as previous studies involved the use of both techniques in all patients. We therefore conducted a trial in which patients were randomized to undergo one or other exploration. METHODS: All consecutive patients referred for obscure gastrointestinal bleeding were randomized between CE and PE as the first-line exploration. The alternative method was only used if the first-line method revealed no definite bleeding source, or if required for clinical reasons during follow-up. RESULTS: CE and PE, used as the first-line exploration, identified a bleeding source in 20 of 40 patients and 9 of 38 patients, respectively (50% vs 24%; P = .02). CE missed lesions in 8% of patients, and all these lesions were located in sites accessible to standard endoscopy. PE missed lesions in 26% of patients. At the end of the 12-month follow-up period, the strategy based on CE as first-line exploration followed by PE if necessary only was similar to PE followed by CE in terms of diagnostic yield, clinical outcome, and therapeutic impact, but reduced the percentage of patients needing the alternative exploration (25% vs 79%; P < .001). CONCLUSIONS: CE has a higher diagnostic yield than PE in obscure gastrointestinal bleeding, and a strategy based on CE as first-line exploration avoids unnecessary explorations.