Off the wall: incidental paraspinal and pelvic muscle pathology on abdominopelvic imaging.

As the use of cross-sectional abdominal and pelvic imaging has increased exponentially in the past several decades, incidental musculoskeletal findings have become commonplace. These are often unrelated to the indication for the examination and are frequently referred to as the "radiologist's blind spot" on these studies. The differential diagnosis for abnormalities of the paraspinal and pelvic musculature is, in many cases, quite different from the anterior abdominal wall muscles. Furthermore, due to their relatively deep location, pathology involving the former muscle groups is more likely to be clinically occult, often presenting only incidentally when the patient undergoes cross-sectional imaging. Effective treatment of diseases of these muscles is dependent on adherence to a diverse set of diagnostic and treatment algorithms. The purpose of this review article is to familiarize the radiologist with the unique pathology of these often-overlooked muscles of the abdomen and pelvis.

Hereditary renal tumor syndromes: imaging findings and management strategies.

OBJECTIVE: It is not rare for the radiologist to identify multiple renal masses and be the first to raise the possibility of a hereditary renal tumor syndrome. Characteristic renal and extrarenal imaging findings aid in making the correct diagnosis. The imaging findings, screening guidelines, and management techniques for the most common hereditary renal tumor syndromes are reviewed. CONCLUSION: Hereditary renal tumor syndromes have specific screening guidelines and unique management techniques in which imaging plays a central role.

Improvement of hyperemic myocardial oxygen extraction fraction estimation by a diffusion-prepared sequence.

Myocardial oxygen extraction fraction (OEF) during hyperemia can be estimated using a double-inversion-recovery-prepared T(2)-weighted black-blood sequence. Severe irregular electrocardiogram (ECG) triggering due to elevated heart rate and/or arrhythmias may render it difficult to adequately suppress the flowing left ventricle blood signal and thus potentially cause errors in the estimates of myocardial OEF. Thus, the goal of this study was to evaluate another black-blood technique, a diffusion-weighted-prepared turbo spin echo sequence for its ability to determine regional myocardial OEF during hyperemia. Control dogs and dogs with acute coronary artery stenosis were imaged with both the double-inversion-recovery- and diffusion-weighted-prepared turbo spin echo sequences at rest and during either dipyridamole or dobutamine hyperemia. Validation of MRI OEF estimates was performed using blood sampling from the artery and coronary sinus in control dogs. The two methods showed comparable correlations with blood sampling results (R(2) = 0.9). Similar OEF estimations for all dogs were observed, except for the group of dogs with severe coronary stenosis during dobutamine stress. In these dogs, the diffusion-weighted method provided more physiologically reasonable OEF (hyperemic OEF = 0.75 +/- 0.08 versus resting OEF of 0.6) than the double-inversion-recovery method (hyperemic OEF = 0.56 +/- 0.10). Diffusion-weighted preparation may be a valuable alternative for more accurate oxygenation measurements during irregular ECG-triggering.

The chorionic bump in an ectopic pregnancy.

The chorionic bump, an irregular, convex bulge of the choriodecidual surface into the gestational sac (GS), is a recently described, uncommon abnormality of the 1st-trimester GS and is associated with a guarded prognosis for early pregnancy. The case of this 42-year-old female demonstrates a previously unreported relationship: a transvaginal sonographic finding of a chorionic bump associated with a spontaneous tubal ectopic pregnancy. This might support the hypothesis that the chorionic bump represents a small hematoma that bulges into the GS.

Resting myocardial perfusion quantification with CMR arterial spin labeling at 1.5 T and 3.0 T.

BACKGROUND: The magnetic resonance technique of arterial spin labeling (ASL) allows myocardial perfusion to be quantified without the use of a contrast agent. This study aimed to use a modified ASL technique and T1 regression algorithm, previously validated in canine models, to calculate myocardial blood flow (MBF) in normal human subjects and to compare the accuracy and repeatability of this calculation at 1.5 T and 3.0 T. A computer simulation was performed and compared with experimental findings. RESULTS: Eight subjects were imaged, with scans at 3.0 T showing significantly higher T1 values (P < 0.001) and signal-to-noise ratios (SNR) (P < 0.002) than scans at 1.5 T. The average MBF was found to be 0.990 +/- 0.302 mL/g/min at 1.5 T and 1.058 +/- 0.187 mL/g/min at 3.0 T. The repeatability at 3.0 T was improved 43% over that at 1.5 T, although no statistically significant difference was found between the two field strengths. In the simulation, the accuracy and the repeatability of the MBF calculations were 61% and 38% higher, respectively, at 3.0 T than at 1.5 T, but no statistically significant differences were observed. There were no significant differences between the myocardial perfusion data sets obtained from the two independent observers. Additionally, there was a trend toward less variation in the perfusion data from the two observers at 3.0 T as compared to 1.5 T. CONCLUSION: This suggests that this ASL technique can be used, preferably at 3.0 T, to quantify myocardial perfusion in humans and with further development could be useful in the clinical setting as an alternative method of perfusion analysis.

The myriad of diseases that present with polyostotic bone lesions.

Many diseases result in polyostotic bone lesions including benign entities, benign entities with malignant potential, intermediate entities, and malignant entities. Imaging plays a key role in identifying complications of these disorders, most importantly malignant transformation of a benign lesion. The most common polyostotic bone lesions are reviewed and examples of malignant transformation are highlighted.