Three Dimensional Ultra-short Echo Time MRI Can Depict Cholesterol Components of Gallstones Bright.

PURPOSE: Non-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO3 (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline. METHODS: Fourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared. RESULTS: BC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, -10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, -11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = -0.885, (P < 0.0001), UTE MRI first echo r = -0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016). CONCLUSION: UTE MRI and UTE subtraction can depict CC bright.

Delay by patients and doctors in treatment of Pancoast tumor.

PURPOSE: Long delays in diagnosis and treatment of Pancoast tumor have been reported but the reasons for these delays have yet to be fully considered. The aim of this study was to assess recent delays in diagnosis and treatment of Pancoast tumor and to determine the reasons for the delays. PATIENTS AND METHODS: We identified Pancoast tumors in patients with lung cancer referred to the radiation department of a city hospital between September 1999 and August 2004. From interviews conducted by a radiation oncologist and review of the medical records, delay due to a patient was calculated as the interval between the onset of symptoms and presentation to a physician, and delay due to a doctor as the interval between the presentation and the definitive treatment. The overall treatment delay was calculated as the sum of those delays. Radiological workups were also reviewed for errors, and the effect of any errors on the delays was estimated. RESULTS: The study population included 42 men and six women with a median age of 65.5 years at presentation. Treatment delay ranged widely from 38 to 400 days (mean 164.0): delay due to patients ranged from 0 to 371 days (mean 55.8), accounting for 34% of the mean treatment delay; delay due to doctors ranged from 14 to 349 days (mean 108.2), and accounted for the remaining (66%) mean treatment delay. In 166 radiological studies reviewed, 98 radiological errors (59%) were identified in 28 patients (58%). These patients waited an additional mean of 88.4 days for correct radiological interpretation, accounting for 48% of the mean doctors' delay. Thus, the mean doctors' delay with radiological errors was significantly longer than that without radiological errors (p < 0.05). CONCLUSIONS: Treatment delay for Pancoast tumor was relatively long, and approximately two-thirds of the delay was due to doctors, mainly because of errors in radiology.