Flexible endoscopy is enough diagnostic prior to loop ileostomy reversal

PURPOSE

This study investigates whether contrast enema (CE) and flexible endoscopy (FE) should be performed routinely after low anterior resection (LAR) before ileostomy reversal. Additionally, the impact of previous anastomotic leakage (AL) on diagnostic test accuracy (DTA) was assessed.

METHODS

This is a retrospective analysis of prospectively collected tertiary care data of two centers. Consecutive rectal cancer patients undergoing LAR with loop ileostomy formation were included. Before ileostomy reversal, all patients were assessed by CE and FE. DTA of FE and CE for asymptomatic AL in patients who had previously suffered from clinically relevant AL (group 1) compared with those without apparent AL after LAR (group 0) were assessed separately.

RESULTS

Two hundred ninety-three patients were included in the analysis, 86 in group 1 and 207 in group 0. Overall sensitivity for detection of asymptomatic AL was 76% (FE) and 60% (CE). Specificity was 100% for both tests. DTA of FE was equal or superior to CE in all subgroups. Prevalence of asymptomatic AL at the time of testing was 1.4% in group 0 and 25.6% in group 1.

CONCLUSION

Flexible endoscopy is the more accurate diagnostic test for the detection of asymptomatic anastomotic leaks prior to ileostomy reversal. Contrast enema showed no gain of information. In the group without complications after the initial rectal resection, 104 must be tested to find one leak prior to reversal. In those patients, routine diagnostic testing additional to digital rectal examination may be questioned.

Comparison of organ-specific-radiation dose levels between 70 kVp perfusion CT and standard tri-phasic liver CT in patients with hepatocellular carcinoma using a Monte-Carlo-Simulation-based analysis platform

Purpose

The aim of this study was to systematically compare organ-specific-radiation dose levels between a radiation dose optimized perfusion CT (dVPCT) protocol of the liver and a tri-phasic standard CT protocol of the liver using a Monte-Carlo-Simulation-based analysis platform.

Methods and materials

The complete CT data of 52 patients (41 males; mean age 65 ± 12) with suspected HCC that underwent dVPCT examinations on a 3rd generation dual-source CT (Somatom Force, Siemens) with a dose optimized tube voltage of 70 kVp or 80 kVp were exported to an analysis platform (Radimetrics, Bayer). The dVPCT studies were matched with a reference group of 50 patients (35 males; mean age 65 ± 14) that underwent standard tri-phasic CT (sCT) examinations of the liver with 130 kVp using the calculated water-equivalent-diameter of the patients. The analysis platform was used for the calculation of the organ-specific effective dose (ED) as well as global radiation-dose parameters (ICRP103).

Results

The organ-specific ED of the dVPCT protocol was statistically significantly lower when compared to the sCT in 14 of 21, and noninferior in a total of 18 of 21 examined items (all p < 0.05). The EDs of the dVPCT examinations were especially in the dose sensitive organs such as the red marrow (17.3 mSv vs 24.6 mSv, p = < 0.0001) and the liver (33.3 mSv vs 46.9 mSv, p = 0.0003) lower when compared to the sCT.

Conclusion

Our results suggest that dVPCT performed at 70 or 80 kVp compares favorably to sCT performed with 130 kVp with regard to effective organ dose levels, especially in dose sensitive organs, while providing additional functional information which is of paramount importance in patients undergoing novel targeted therapies.