Marta E. Heilbrun

Correlation between levator ani muscle injuries on magnetic resonance imaging and fecal incontinence, pelvic organ prolapse, and urinary incontinence in primiparous women

OBJECTIVE The objective of the study was to correlate the presence of major levator ani muscle (LAM) injuries on magnetic resonance imaging (MRI) with fecal incontinence (FI), pelvic organ prolapse (POP), and urinary incontinence (UI) in primiparous women 6-12 months postpartum. STUDY DESIGN A published scoring system was used to characterize LAM injuries on MRI dichotomously (MRI negative, no/mild vs MRI positive, major). RESULTS Major LAM injuries were observed in 17 of 89 (19.1%) women who delivered vaginally with external anal sphincter (EAS) injuries, 3 of 88 (3.5%) who delivered vaginally without EAS injury, and 0 of 29 (0%) who delivered by cesarean section before labor (P=.0005). Among women with EAS injuries, those with major LAM injuries trended toward more FI, 35.3% vs 16.7% (P=.10) and POP, 35.3% vs 15.5% (P=.09), but not UI (P=1.0). CONCLUSION These data support the growing body of literature suggesting that both EAS and LAM are important for fecal continence and that multiple injuries contribute to pelvic floor dysfunction.

Radiation and Chest CT Scan Examinations: What Do We Know?

In the past 3 decades, the total number of CT scans performed has grown exponentially. In 2007, > 70 million CT scans were performed in the United States. CT scan studies of the chest comprise a large portion of the CT scans performed today because the technology has transformed the management of common chest diseases, including pulmonary embolism and coronary artery disease. As the number of studies performed yearly increases, a growing fraction of the population is exposed to low-dose ionizing radiation from CT scan. Data extrapolated from atomic bomb survivors and other populations exposed to low-dose ionizing radiation suggest that CT scan-associated radiation may increase an individuals lifetime risk of developing cancer. This finding, however, is not incontrovertible. Because this topic has recently attracted the attention of both the scientific community and the general public, it has become increasingly important for physicians to understand the cancer risk associated with CT scan and be capable of engaging in productive dialogue with patients. This article reviews the current literature on the public health debate surrounding CT scan and cancer risk, quantifies radiation doses associated with specific studies, and describes efforts to reduce population-wide CT scan-associated radiation exposure. CT scan examinations of the chest, including CT scan pulmonary and coronary angiography, high-resolution CT scan, low-dose lung cancer screening, and triple rule-out CT scan, are specifically considered.

Comparison of Whole-Body PET/CT, Dedicated High-Resolution Head and Neck PET/CT, and Contrast-Enhanced CT in Preoperative Staging of Clinically M0 Squamous Cell Carcinoma of the Head and Neck

The purpose of this study was to compare optimized whole-body (WB) and dedicated high-resolution contrast-enhanced PET/CT protocols and contrast enhanced CT in the preoperative staging of primary squamous cell carcinoma of the head and neck. Methods: A total of 44 patients with clinically M0 squamous cell carcinoma of the head and neck underwent primary tumor resection and neck dissection within 6 wk of diagnostic imaging. Imaging consisted of a standard WB PET/CT protocol without intravenous contrast enhancement, followed by a high-resolution dedicated head and neck (HN) PET/CT protocol, which included diagnostic-quality contrast-enhanced CT (CECT). Imaging results were compared with histopathology. A 5-point scale was used to designate primary tumor localization and the presence of lymph node metastasis on a per-patient and per-level basis. For cervical nodes, receiver-operating-characteristic curves were generated to determine the differences in performance between the WB and HN PET/CT protocols and CECT. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated for primary tumor and cervical nodes. Results: No statistical difference was observed between WB and HN PET/CT protocols, both of which significantly outperformed CECT, in the evaluation of the primary tumor. The performance of the HN PET/CT protocol was superior to that of the WB PET/CT in the detection of cervical node metastases, achieving statistical significance on a per-level basis and approaching significance on a per-patient basis, with the greatest advantage in the detection of small positive lymph nodes (<15 mm). No significant difference was observed between the WB PET/CT protocol and CECT in nodal staging, either on a per-patient or on a per-level basis. Conclusion: The primary advantage of the dedicated HN PET/CT protocol over the WB protocol or CECT in the staging of head and neck cancer is in the detection of small lymph node metastases.

CT-Guided Biopsy for the Diagnosis of Renal Tumors Before Treatment with Percutaneous Ablation

OBJECTIVE Percutaneous thermal ablation is an emerging technique in the management of renal cell carcinoma (RCC), with greatest efficacy in tumors < or = 3 cm. The purpose of this retrospective study was to evaluate the role and utility of pretreatment CT-guided biopsy in patients referred for percutaneous thermal ablation of renal tumors. CONCLUSION Less than 5% of samples in our study were benign, and 11.8% were nondiagnostic. Biopsy in smaller lesions was less accurate; therefore biopsy is less useful for these renal lesions. Because fine-needle aspiration (FNA) has higher sensitivity than core biopsy, an appropriate algorithm may be to begin with FNA and reserve core biopsy for cases in which an onsite cytotechnologist is unavailable or deems the sample of inadequate cellularity.

Imaging of Müllerian duct anomalies.

Müllerian duct anomalies (MDAs) are relatively common disorders that are particularly relevant in patients with infertility, recurrent pregnancy loss, or a history of preterm labor. Accurate characterization of MDAs is crucial to the implementation of appropriate treatment. Various imaging modalities have been used in the evaluation of MDAs, including hysterosalpingography, ultrasound, and magnetic resonance imaging (MRI). Although hysterosalpingography and ultrasound may suggest a Müllerian duct anomaly, further evaluation by MRI is often required. MRI is the best imaging method available because of its superior ability to reliably visualize complex uterovaginal anatomy.

Adipose Tissue Density, a Novel Biomarker Predicting Mortality Risk in Older Adults

BACKGROUND Knowledge of adipose composition in relation to mortality may help delineate inconsistent relationships between obesity and mortality in old age. We evaluated relationships between abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) density, mortality, biomarkers, and characteristics. METHODS VAT and SAT density were determined from computed tomography scans in persons aged 65 and older, Health ABC (n = 2,735) and AGES-Reykjavik (n = 5,131), and 24 nonhuman primates (NHPs). Associations between adipose density and mortality (4-13 years follow-up) were assessed with Cox proportional hazards models. In NHPs, adipose density was related to serum markers and tissue characteristics. RESULTS Higher density adipose tissue was associated with mortality in both studies with adjustment for risk factors including adipose area, total fat, and body mass index. In women, hazard ratio and 95% CI for the densest quintile (Q5) versus least dense (Q1) for VAT density were 1.95 (1.36-2.80; Health ABC) and 1.88 (1.31-2.69; AGES-Reykjavik) and for SAT density, 1.76 (1.35-2.28; Health ABC) and 1.56 (1.15-2.11; AGES-Reykjavik). In men, VAT density was associated with mortality in Health ABC, 1.52 (1.12-2.08), whereas SAT density was associated with mortality in both Health ABC, 1.58 (1.21-2.07), and AGES-Reykjavik, 1.43 (1.07-1.91). Higher density adipose tissue was associated with smaller adipocytes in NHPs. There were no consistent associations with inflammation in any group. Higher density adipose tissue was associated with lower serum leptin in Health ABC and NHPs, lower leptin mRNA expression in NHPs, and higher serum adiponectin in Health ABC and NHPs. CONCLUSION VAT and SAT density provide a unique marker of mortality risk that does not appear to be inflammation related.

Comparison of 18F-fluorodeoxyglucose and 18F- fluorothymidine PET in differentiating radiation necrosis from recurrent glioma

Purpose The objective was to compare 18F-fluorodeoxyglucose (FDG) and 18F-fluorothymidine (FLT) PET in differentiating radiation necrosis from recurrent glioma. Materials and Methods Visual and quantitative analyses were derived from static FDG PET and static and dynamic FLT PET in 15 patients with suspected recurrence of treated grade 2 glioma or worse with a new focus of Gd contrast enhancement on MRI. For FDG PET, SUVmax and the ratio of lesion SUVmax to the SUVmean of contralateral white matter were measured. For FLT PET, SUVmax and Patlak-derived metabolic flux parameter Kimax were measured for the same locus. A 5-point visual confidence scale was applied to FDG PET and FLT PET. Receiver operating curve analysis was applied to visual and quantitative results. Differences between recurrent tumor and radiation necrosis were tested by Kruskal-Wallis analysis. On the basis of follow-up Gd-enhanced MRI, lesion-specific recurrent tumor was defined as a definitive increase in size of the lesion, and radiation necrosis was defined as stability or regression. Results For FDG SUVmax, the FDG ratio of lesion–white matter, and FLT Kimax, there was a significant difference between mean values for recurrent tumor and radiation necrosis. Recurrent tumor was best identified by the FDG ratio of lesion–contralateral normal white matter (area under the curve of 0.98, confidence interval of 0.91 to 1.00, sensitivity of 100%, and specificity of 75% for an optimized cutoff value of 1.82). Conclusions Both quantitative and visual determinations allow accurate differentiation between recurrent glioma and radiation necrosis by both FDG and FLT PET. In this small series, FLT PET offers no advantage over FDG PET.

Assessing the role of magnetic resonance imaging in the management of gravid patients at risk for placenta accreta.

RATIONALE AND OBJECTIVES The role of magnetic resonance imaging (MRI) in the diagnosis of placenta accreta remains uncertain. The purpose of this study was to evaluate the incremental benefit of MRI after ultrasound (US) for a large cohort of gravid patients at risk for a placenta accreta. MATERIALS AND METHODS A retrospective review of outcomes in women with risk factors for a placenta accreta between November 1995 and February 2008 was performed. Inclusion criteria were high-risk women with abnormal placenta implantation on US or operative diagnosis of placenta accreta, with or without a prenatal MRI. Delivery mode, diagnosis, and transfusion requirements were compared. RESULTS Ranging in age from 19 to 43 years, with zero to five prior cesarean sections, 139 women met inclusion criteria. The MRI was performed in 28.7% (40/139). US, MRI, and operative diagnoses were highly correlated (P < .001). Women who underwent both US and MRI were more likely to deliver by cesarean hysterectomy (P < .001). When the cohort is stratified by outcome diagnosis (normal, previa, accreta), no difference in delivery mode is found; regardless of whether subjects were imaged by US alone or US and MRI. Transfusion requirements were highest in the US and MRI group (mean of 3.9 units vs. 0.9 units in the US only group, P < .001). CONCLUSION This study fails to demonstrate that the incremental use of MRI for placenta accreta changes delivery mode in stratified analysis. Patients who underwent both US and MRI were most likely to have a cesarean hysterectomy delivery, and required more blood products, suggesting that undergoing tests may be indicative of an abnormal and at risk patient population.

The Cost-Effectiveness of Immediate Treatment, Percutaneous Biopsy and Active Surveillance for the Diagnosis of the Small Solid Renal Mass: Evidence From a Markov Model

PURPOSE The most effective diagnostic strategy for the very small, incidentally detected solid renal mass is uncertain. We assessed the cost-effectiveness of adding percutaneous biopsy or active surveillance to the diagnosis of a 2 cm or less solid renal mass. MATERIALS AND METHODS A Markov state transition model was developed to observe a hypothetical cohort of healthy 60-year-old men with an incidentally detected, 2 or less cm solid renal mass, comparing percutaneous biopsy, immediate treatment and active surveillance. The primary outcomes assessed were the incremental cost-effectiveness ratio measured by cost per life-year gained at a willingness to pay threshold of

Tripalmitoyl-S-Glyceryl-Cysteine-Dependent OspA Vaccination of Toll-Like Receptor 2-Deficient Mice Results in Effective Protection from Borrelia burgdorferi Challenge

50,000. Model results were assessed by sensitivity analysis. RESULTS Immediate treatment was the highest cost, most effective diagnostic strategy, providing the longest overall survival of 18.53 life-years. Active surveillance was the lowest cost, least effective diagnostic strategy. On cost-effectiveness analysis using a societal willingness to pay threshold of