Suitability of T(1Gd) as the dGEMRIC index at 1.5T and 3.0T.

Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is based on the theory that Gd-DTPA(2-) will distribute in inverse relation to cartilage glycosaminoglycan (GAG). T(1Gd) (T(1) after penetration of a 0.2 mmol/kg dose of Gd-DTPA(2-)) has been used as the dGEMRIC index, although (1/T(1Gd)-1/T(1o)) should be more representative of Gd-DTPA(2-) concentration (where T(1o) = T(1) before contrast). T(1o) and T(1Gd) were measured in 20 volunteers at both 1.5T and 3T and the correlation between the metrics of T(1Gd) and (1/T(1Gd)-1/T(1o)) was calculated. There was a high correlation coefficient between the two metrics at both field strengths, with R = 0.94, 0.93, and 0.90 for central medial femur, posterior medial femur, and medial tibia, respectively, at 1.5T and 0.87, 0.94, 0.96 at 3T. In all cases P < 0.0001. Therefore, these data suggest that, for native cartilage, the current practice of measuring T(1Gd) (but not also T(1o)) is adequate at both 1.5T and 3T.     

99mTc-IMMU-4 monoclonal antibody scan in colorectal cancer. A prospective study.

A blinded prospective study of 34 patients with colorectal adenocarcinoma using the Fab' fragment of the anticarcinoembryonic antigen monoclonal antibody type IMMU-4 labeled with technetium 99m was conducted to compare, on a lesion-by-lesion basis, the findings of radioimmunoscintigraphy, preoperative computed tomography, and exploratory celiotomy. Of 115 lesions detected at surgery, 113 were adenocarcinoma. Radioimmunoscintigraphy detected 59 lesions and computed tomography detected 62; both studies combined detected 72. Twenty-nine (54%) lesions missed by radioimmunoscintigraphy and 24 (45%) missed by computed tomography were 1 cm or smaller. When both studies were combined, the sensitivities were 90%, 24%, and 42%, and the specificities were 52%, 86%, and 61% for hepatic, extrahepatic intra-abdominal, and pelvic lesions, respectively. In 10 patients, additional information obtained with the radioimmunoscintigram could have altered the treatment of these patients. In this study, radioimmunodetection scan was complementary to computed tomographic scan in the examination of patients with colorectal carcinoma.     

Psychological Characteristics and Pain Frequency Are Associated With Experimental Pain Sensitivity in Pediatric Patients With Sickle Cell Disease

Sickle cell disease (SCD) is associated with episodes of severe vaso-occlusive pain beginning in infancy with a subset of patients with SCD transitioning to chronic pain. Response to experimental pain using quantitative sensory testing in these patients suggests altered pain processing. The objectives of this study were to characterize sensitivity to multiple modalities of experimental pain stimuli and to interrogate the relationship of psychological covariates, clinical pain burden, and pain-related outcomes to experimental pain sensitivity in children with SCD compared with healthy individuals of similar age and sex. Cross-sectional assessments of psychological characteristics were performed, and quantitative sensory testing methods were used to measure experimental pain sensitivity in children age 8 to 21 years. Anxiety, depressive symptoms, catastrophizing, and somatization were found to be associated with increased sensitivity to experimental pain stimuli. Increased frequency of painful episodes in SCD was associated with decreased sensitivity to heat pain and decreased mechanical temporal summation. These data suggest that careful consideration be given to psychological factors, age, sex, and clinical burden of pain when studying response to experimental pain in SCD.

Appropriate and inappropriate imaging rates for prostate cancer go hand in hand by region, as if set by thermostat

Policy makers interested in containing health care costs are targeting regional variation in utilization, including the use of advanced imaging. However, bluntly decreasing utilization among the highest-utilization regions may have negative consequences. In a cross-sectional study of prostate cancer patients from 2004 to 2005, we found that regions with lower rates of inappropriate imaging also had lower rates of appropriate imaging. Similarly, regions with higher overall imaging rates tended to have not only higher rates of inappropriate imaging, but also higher rates of appropriate imaging. In fact, men with high-risk prostate cancer were more likely to receive appropriate imaging if they resided in areas with higher rates of inappropriate imaging. This "thermostat model" of regional health care utilization suggests that poorly designed policies aimed at reducing inappropriate imaging could limit access to appropriate imaging for high-risk patients. Health care organizations need clearly defined quality metrics and supportive systems to encourage appropriate treatment for patients and to ensure that cost containment does not occur at the expense of quality.