Usefulness of doppler techniques in the diagnosis of peripheral iatrogenic pseudoaneurysms secondary to minimally invasive interventional and surgical procedures: imaging findings and diagnostic performance study.

The pseudoaneurysm (PA) is a perfused sac directly connecting with the arterial lumen by an interruption of the vessel wall continuity, more commonly secondary to trauma or iatrogenic causes. Aim of our study was to determine the accuracy and usefulness of Doppler techniques in the diagnosis of peripheral iatrogenic PAs secondary to minimally invasive procedures. From a three year prospective research, 20 Duplex Ultrasound (DUS) studies in as many patients presenting with periarterial pulsating mass clinically suspected for PA secondary to minimally invasive procedures were selected. The PA final diagnosis was confirmed by angiography in 12 patients (60% cases), by computed tomography angiography in 5 patients (25%), by surgery in 2 patients (10%), and by magnetic resonance angiography in 1 patient (5%). The vessels involved by PA formation were: common femoral artery in 8 cases (40%); superficial femoral artery in 4 cases (20%); brachial artery in 3 cases (15%); popliteal artery in 2 cases (10%); superficial temporal artery (STA) in 2 cases (10%); dorsal medial digital artery of the foot in 1 case (5%). Our study confirmed the usefulness of doppler techniques in the diagnosis of peripheral iatrogenic PAs. Specifically, a sensitivity of 90-95%, a specificity of 100% and predictive values of 100% (VPP) and 83-90% (VPN) were reported. The radiologist must always suspect a PA in the differential diagnosis of lesions contiguous to an artery vessel. This is to prevent potential complications such as e.g. massive haemorrhage. In this order, DUS allows a careful selection of patients who require to undergo in-depth imaging methods or surgical therapy, thus contributing to a significant reduction of contrast medium and exposure to ionizing radiation.

Post-treatment fistulas in patients with rectal cancer: MRI with rectal superparamagnetic contrast agent.

MRI is the standard modality in the pre- and post-treatment evaluation of patients with rectal cancer, particularly in those cases with locally advanced disease. We routinely employ a superparamagnetic iron oxide (SPIO) contrast enema to distend the rectal lumen and achieve maximal tumor-to-lumen contrast gradient. This practice also allowed the identification of a fistula in 24% of patients treated for rectal cancer. Contrast agent-related low intensity signal could be seen filling the tract and eventually opacifying surrounding organs (i.e., vagina) or collections (i.e., presacral abscess). Fistula formation after radiochemotherapy and surgery for rectal cancer is not uncommon. MRI with dark lumen contrast enema allows an effective demonstration of this complication in a high number of patients.

Capsule endoscopy versus enteroclysis in the detection of small-bowel involvement in Crohn's disease: a prospective trial.

BACKGROUND & AIMS: The aim of this study was to prospectively compare the diagnostic yield of wireless capsule endoscopy (WCE) and enteroclysis in evaluating the extent of small-bowel involvement in Crohn's disease (CD). METHODS: Thirty-one patients (20 men; mean age, 43 y) with endoscopically and histologically proven CD underwent enteroclysis as their initial examination, followed by WCE. The radiologist who performed the small-bowel enema was blinded to the results of standard index endoscopy, which included retrograde ileoscopy. Gastroenterologists were blinded to the results of enteroclysis at the time of interpretation of the WCE video. RESULTS: Abnormal findings were documented in 8 of 31 patients by using enteroclysis and in 22 of 31 patients by using WCE (25.8% vs. 71%, P < .001). In 16 patients with known involvement of the terminal ileum, the diagnostic yield of WCE vs enteroclysis was significantly superior (89% vs 37%, P < .001). In 15 patients without lesions in the terminal ileum, abnormal findings in the proximal small bowel were detected in 7 (46%) patients by WCE and only in 2 (13%) patients by enteroclysis (P < .001). The capsule detected all but 2 lesions diagnosed by enteroclysis. WCE detected additional lesions that were not detected by enteroclysis in 45% of cases. CONCLUSIONS: WCE is superior to enteroclysis in estimating the presence and extent of small-bowel CD. WCE may be a new gold standard for diagnosing ileal involvement in patients with CD without strictures and fistulae.