Pari V. Pandharipande

Pregnant Patients Suspected of Having Acute Appendicitis: Effect of MR Imaging on Negative Laparotomy Rate and Appendiceal Perforation Rate

PURPOSE To investigate the effect of magnetic resonance (MR) imaging on the negative laparotomy rate (NLR) and the perforation rate (PR) in pregnant patients suspected of having acute appendicitis (AA) and to assess the need for computed tomography (CT) in this setting. MATERIALS AND METHODS The data of 148 consecutive pregnant patients (mean age, 29 years; age range, 15-42 years; mean gestational age, 20 weeks; gestational age range, 4-37 weeks) who were clinically suspected of having AA and examined with MR imaging between March 2002 and August 2007 were retrospectively analyzed in an institutional review board-approved HIPAA-compliant protocol. One hundred forty patients underwent ultrasonography (US) before MR imaging. The clinical and laboratory data and the findings of the initial US and MR image interpretations were recorded and analyzed at Student t and Fisher exact testing. The NLR and PR were calculated. RESULTS Fourteen (10%) patients had AA, and perforation occurred in three (21%) of them. US results were positive for AA in five (36%) patients with proved AA. MR results were positive in all 14 patients with AA. MR results were negative in 125 of the 134 patients without AA; there were nine false-positive cases (two positive, seven inconclusive). Among the patients without AA, the normal appendix could be visualized on US images in less than 2% (two of 126) of cases and on MR images in 87% (116 of 134) of cases (P < .0001). Twenty-seven (18%) patients underwent surgical exploration, and eight of them had negative laparotomy results, yielding an NLR of 30% and a PR of 21% (three of 14 patients). Only four (3%) patients underwent CT. CONCLUSION For pregnant patients clinically suspected of having AA, use of MR imaging yields favorable combinations of NLR and PR compared with previously reported values. The radiation exposure associated with CT examination can be avoided in most cases.

Renal Mass Biopsy to Guide Treatment Decisions for Small Incidental Renal Tumors: A Cost-effectiveness Analysis

PURPOSE To evaluate the effectiveness, cost, and cost-effectiveness of using renal mass biopsy to guide treatment decisions for small incidentally detected renal tumors. MATERIALS AND METHODS A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for patients with small (< or = 4-cm) renal tumors. Two strategies were compared: renal mass biopsy to triage patients to surgery or imaging surveillance and empiric nephron-sparing surgery. The model incorporated biopsy performance, the probability of track seeding with malignant cells, the prevalence and growth of benign and malignant tumors, treatment effectiveness and costs, and patient outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference under a willingness-to-pay threshold of

Radiofrequency ablation versus nephron-sparing surgery for small unilateral renal cell carcinoma: cost-effectiveness analysis.

75,000 per quality-adjusted life-year (QALY). Effects of changes in key parameters on strategy preference were evaluated in sensitivity analysis. RESULTS Under base-case assumptions, the biopsy strategy yielded a minimally greater quality-adjusted life expectancy (4 days) than did empiric surgery at a lower lifetime cost (

The Economic Burden of Incidentally Detected Findings

3466), dominating surgery from a cost-effectiveness perspective. Over the majority of parameter ranges tested in one-way sensitivity analysis, the biopsy strategy dominated surgery or was cost-effective relative to surgery based on a

Comparative effectiveness research: what it means for radiology.

75,000-per-QALY willingness-to-pay threshold. In two-way sensitivity analysis, surgery yielded greater life expectancy when the prevalence of malignancy and propensity for biopsy-negative cancers to metastasize were both higher than expected or when the sensitivity and specificity of biopsy were both lower than expected. CONCLUSION The use of biopsy to guide treatment decisions for small incidentally detected renal tumors is cost-effective and can prevent unnecessary surgery in many cases.

ACR Appropriateness Criteria Staging and Follow-up of Ovarian Cancer

PURPOSE To evaluate the relative cost-effectiveness of percutaneous radiofrequency (RF) ablation versus nephron-sparing surgery (NSS) in patients with small (<or=4-cm) renal cell carcinoma (RCC), given a commonly accepted level of societal willingness to pay. MATERIALS AND METHODS A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for 65-year-old patients with a small RCC treated with RF ablation or NSS. The model incorporated RCC presence, treatment effectiveness and costs, and short- and long-term outcomes. An incremental cost-effectiveness analysis was performed to identify treatment preference under an assumed

Solid Renal Masses: What the Numbers Tell Us

75,000 per quality-adjusted life-year (QALY) societal willingness-to-pay threshold level, within proposed ranges for guiding implementation of new health care interventions. The effect of changes in key parameters on strategy preference was addressed in sensitivity analysis. RESULTS By using base-case assumptions, NSS yielded a minimally greater average quality-adjusted life expectancy than did RF ablation (2.5 days) but was more expensive. NSS had an incremental cost-effectiveness ratio of

Improving diversity, inclusion, and representation in radiology and radiation oncology part 2: Challenges and recommendations

1,152,529 per QALY relative to RF ablation, greatly exceeding

Improving Diversity, Inclusion, and Representation in Radiology and Radiation Oncology Part 1: Why These Matter

75,000 per QALY. Therefore, RF ablation was considered preferred and remained so if the annual probability of post-RF ablation local recurrence was up to 48% higher relative to that post-NSS. NSS preference required an estimated NSS cost reduction of

DWI for Renal Mass Characterization: Systematic Review and Meta-Analysis of Diagnostic Test Performance

7500 or RF ablation cost increase of