Three-dimensional ultrasonography, virtual coloscopy and endorectal magnetic resonance imaging in the diagnosis of complicated inflammatory bowel disease

Three-dimensional endoanal ultrasonography in daily proctological practice

Three-dimensional endoanal ultrasonography (3D-EAUS) provides unequalled quality in terms of the anatomical image of the anal canal and sphincter complex. In less than one minute it produces a three-dimensional "cube" that can be manipulated in all spatial dimensions, then archived. In just a few years it has become a new gold standard exploration in proctology. In addition to image quality, 3D-EAUS has the advantage of being easily and rapidly performed, well-tolerated and moderate in cost. For anal incontinence, 3D-EAUS contributes to the identification of sphincter defects. The anatomy of the sphincters can be evaluated spatially. Simple scoring systems with good reproducibility and readily applicable in routine practice can be used to evaluate the "damaged" sphincter volume. For the management of anoperineal suppurations, 3D-EAUS provides information on the fistulous track(s) and on potential collections. These data are crucial as the choice of treatment and its efficacy depend on accurate topographic assessment of the suppuration and the state of the sphincter apparatus.

Three-dimensional linear endoscopic ultrasound-feasibility of a novel technique applied for the detection of vessel involvement of pancreatic masses

BACKGROUND

Endoscopic ultrasound (EUS) can reliably diagnose and stage pancreatic cancer but is less competent for the differentiation between vascular compression (VC) and invasion (VI).

AIM

Prospective comparison of linear EUS with/without three-dimensional (3D) EUS for vessel involvement in pancreatic cancer to evaluate the feasibility of linear 3D ultrasound.

MATERIAL AND METHODS

Linear echoendoscopy was used to identify the pancreatic tumor, the tumor-vessel relation and for EUS-FNA to obtain tissue diagnosis. Immediately afterwards, 3D image acquisition was performed using a magnetic tracked 3D sensor. The acquisition time was 10-20 s.

RESULTS

EUS results of 22 patients with solid pancreatic lesions were compared to surgical histology. This proved adenocarcinoma in 17 patients and chronic pancreatitis in 5. EUS showed VI in 10 patients, VC in 6, and no vascular involvement (NVI) in 6. Additional 3D evaluation showed VI in 6 patients, VC in 10, and NVI in 6. Surgery proved VI in 7 patients, VC in 9, and NVI in 6. EUS showed VI in 3/5 patients with chronic pancreatitis, 3D showed VC only, while surgery found two patients to have VC and with NVI. In two patients with pancreatic cancer, VI was diagnosed on two dimensional (2D), but VC on 3D evaluation. Surgery showed VC and VI in one each. In the 2D, one patient with NVI had VI on surgery; and on 3D one VC proved to have NVI at surgery. In 1/22 patients the result of 3D was false negative, while 4/22 were false positives and one false negative in conventional EUS.

CONCLUSION

Linear 3D EUS seems feasible for pancreatic evaluation. In addition, linear EUS enhanced the evaluation of vascular involvement of pancreatic lesions, especially in chronic pancreatitis.

Virtual colonoscopy compared with conventional colonoscopy for stricturing postoperative recurrence in Crohn's disease

BACKGROUND

The place of virtual colonoscopy (VC) in patients with Crohn's disease (CD) requiring endoscopic follow-up after surgery is unknown. The authors compared findings from VC versus conventional colonoscopy (CC) for assessing the postoperative recurrence of CD.

METHODS

Sixteen patients with ileocolonic anastomosis for CD were prospectively enrolled from January 2001 to January 2002. Recurrence was assessed by CC according to Rutgeerts et al. VC was performed with a computed tomography scanner, with images examined by three radiologists who were unaware of the endoscopic findings.

RESULTS

CC showed perianastomotic recurrence in 15 of 16 patients. Perianastomotic narrowing or stenosis was detected by VC in 11 of these 15 patients. There were 11 true positive, 1 true negative, 0 false-positive, and 4 false-negative findings (73% sensitivity, 100% specificity, 100% positive predictive value, 20% negative predictive value, 75% accuracy). Among the eight patients showing a rigid stenosis of the anastomosis not allowing passage of the colonoscope, VC detected narrowing or stenosis in seven patients.

CONCLUSIONS

The current findings suggest that although the widespread use of VC in CD is currently not indicated because of possible false-negative findings, this technique may represent an alternative to CC in noncompliant postsurgical patients with a rigid stenosis not allowing passage of the endoscope.