Evaluation of juxtapapillary duodenal diverticula using multiplanar reformation in MDCT: correlation with ERCP findings.

OBJECTIVE: To determine the ability of multidetector computed tomography (MPR-MDCT) to identify and classify the juxtapapillary duodenal diverticulum (JPDD), with ERCP findings as the gold standard. METHODS: We retrospectively reviewed all ERCP examinations (n: 455) performed between January 2010 to December 2018 and selected 105 patients with JPDD as the inclusion criteria. Of those, 28 patients were excluded because of advanced pancreatic carcinoma, incomplete MDCT examinations and biliary catheter insertion. Finally, MDCT examinations of 77 patients with JPDD were assessed for the presence and type of JPDD. RESULTS: MPR-MDCT was able to identify 71 (92.2%) JPDD in 77 cases with 88.9% accuracy, 83.3% sensitivity, and 91.6% specificity in classifying the type of JPDD. MPR-MDCT performed best in determining type 1 JPDD, with accuracy of 95.4% compared with type 2 (83.3%) and type 3 (87.8%). There was no significant difference between age, gender, incidence of biliary stones and pancreatitis between each type of JPDD. No correlation of sizes with types of JPDD was found. CONCLUSIONS: MPR-MDCT can accurately identify and classify JPDD. This information will be useful in determining the difficulty of ERCP.

Physiological 18F-FDG uptake in the normal adult anal canal: evaluation by PET/CT.

OBJECTIVE: Despite their benefit for detecting primary tumors, data for normal 18F-fluoro-2-deoxy-D-glucose (FDG) uptake in the anal canal are insufficient. Here we used positron emission tomography-computed tomography (PET/CT) to determine the uptake of FDG in the normal adult anal canal (AC) and to evaluate its clinical significance compared with that of anal cancer. METHODS: We conducted a retrospective study of-PET/CT images in the anal region, of 201 consecutive patients without symptoms or pathology taken from January 2015 to August 2019, after excluding two patients (one each with Crohn's disease and hemorrhoid). These patients were included in the normal group, and data of eight patients with anal cancer were collected from January 2011 to August 2019 for comparison. FDG uptake was quantitatively evaluated (compared with the maximum standardized uptake value [SUVmax] to the SUVmax values of liver and distal rectum) and qualitatively (compared with background) in early and delayed phases. Normal grade 3 uptake was qualitatively defined as FDG uptake higher than the surrounding muscles. RESULTS: In the normal group, mean anal canal SUVmax of early phase was: 2.26 (range 1.00-6.30), and delayed phase: 2.52 (range 1.00-8.80). Their ratios to liver SUVmax were early: 0.74 (range 0.24-2.25), and delayed: 0.81 (range 0.23-2.32); ratios to rectal SUVmax were early: 0.87 (range 0.30-1.89), and delayed: 0.90 (range 0.30-1.27). Qualitatively, 25 patients (15.4%) had normal grade 3 uptake during the early and delayed phases. In contrast, qualitative data showed that all patients with anal cancer exhibited high FDG uptake in the anal canal. The mean early- and delayed-phase values of SUVmax of the anal canal and anal cancer group were 11.09 (range 5.40-17.73) and 14.23 (range 6.70-22.85), respectively. There was a significant difference between the mean-early and -delayed anal SUVmax values of the normal grade 3 and anal cancer groups. Furthermore, the ratios to liver SUVmax were significantly different between the two groups. CONCLUSIONS: PET/CT scans occasionally showed high FDG uptake in the anal canal of healthy adults. Comparing the SUVmax values of liver FDG uptake may help differentiate between normal tissue and anal cancer.