Does a full bladder aid upper tract visualization in magnetic resonance urography?

The aim of this study was to evaluate whether a full bladder improved the visualization of the upper renal tract during magnetic resonance urography (MRU). Twenty volunteers were recruited into the study. The MRU imaging was carried out on a 1.5-T MR system. Imaging was carried out in the coronal plane using a half-Fourier acquired single-shot turbo-spin-echo technique. All volunteers were examined in two separate MRU studies to visualize the urinary tract. The first study was carried out with a 'full' bladder followed by a study with an 'empty' bladder, leading to a total of 40 examinations. Two radiologists then reviewed maximum intensity projection images from both 'full' and 'empty' studies independently. Both left and right upper tracts were divided into five segments. A three-point grading system was used to evaluate visualization. Excellent visualization = 3, good visualization = 2 and poor visualization = 1. Maximum score per patient was 30. Results were tabulated and analysed using an Excel database. The average score for visualization for the 'full' bladder group was 22.1/30 (73.8%) and the average score for the empty bladder was 16.2/30 (54%). Overall improvement in visualization was 5.9/30 (19.8%). There was strong interobserver agreement, with a concordance value of 92.5%. The MRU carried out in healthy young adult volunteers with a full bladder allows improved visualization of the upper tracts.

Measuring tumor response and shape change on CT: esophageal cancer as a paradigm.

BACKGROUND: Accurate response assessment is essential for evaluating new cancer treatments. We evaluated the impact of Response Evaluation Criteria in Solid Tumors (RECIST), World Health Organization (WHO) criteria and tumor shape on response assessment in patients with metastatic esophageal cancer. PATIENTS AND METHODS: In 19 patients with metastatic esophageal cancer in a phase II trial of bryostatin-1 and paclitaxel, response was retrospectively assessed for 89 lesions with RECIST and WHO criteria on baseline and serial follow-up CT scans. The eccentricity factor (EF) was introduced for measuring the degree to which tumor shape diverges from a perfect sphere [EF = radical1-(LPD/MD)(2), where LPD is the largest perpendicular diameter and MD is the maximal diameter]. RESULTS: The disagreement rate in best overall response categorization between RECIST (unidimensional) and WHO (bidimensional) criteria was 26.3%. Change in eccentricity was significantly greater (P < 0.01) for patients with disagreement (mean 0.31, range 0-0.91). When the short axis was used for unidimensional lymph node measurement, disagreement between WHO and RECIST lessened. CONCLUSIONS: Response assessment by WHO and RECIST differs substantially. Greater change in eccentricity is associated with greater discordance between WHO and RECIST. The discordance between WHO and RECIST may impact on how effective a therapy is judged to be.