Susceptibility-weighted MR imaging helps identify predictors of neurologic prognosis in infants with nonaccidental brain trauma. In a study of 101 children aged 1-32 months, Colbert and colleagues found that intraparenchymal brain microhemorrhages, particularly in the presence of ischemic injury, correlated with poor long-term neurologic outcomes. The researchers concluded that this was likely due to the fact that the microhemorrhages represent foci of axonal injury due to a combination of traumatic and vascular injuries.

In patients undergoing endovascular treatment of ruptured intracranial aneurysms, the rate of thromboembolic events and intraoperative ruptures is significantly affected by the identified risk factors. In the CLARITY (Clinical and Anatomic Results in the Treatment of Ruptured Intracranial Aneurysms) series (782 patients with 782 ruptured aneurysms), Pierot and colleagues found an elevated rate of thromboembolic events during therapy in smokers, patients with aneurysms larger than 10 mm, and patients with wide-necked aneurysms. They also noted that the rate of intraoperative rupture was higher in patients with middle cerebral artery aneurysms. Physicians must take into account these factors and use caution when considering endovascular treatment, the researchers concluded.

In the past decade, there has been a trend toward minimally invasive imaging-guided percutaneous biopsies, and radiologists are performing an increasing share relative to other physicians. In a retrospective study using aggregated Medicare claims data of biopsies performed from 1997 to 2008, Kwan and colleagues found that utilization of imaging-guided percutaneous biopsies and percutaneous needle biopsies increased, while the number of open and endoscopic biopsies decreased and biopsies performed by radiologists increased from 35% to 56%. The researchers concluded that the trend is likely related to the increasing use of advanced imaging modalities for biopsy guidance.

In human hepatocellular carcinoma (HCC), organic anion-Vtransporting polypeptide 8 (OATP8) and multidrug-resistant protein 3 (MRP3) are probably the uptake transporter and export transporter of gadoxetic acid, respectively. Kitao and colleagues found in a study of 40 surgically resected HCCs that the enhancement ratio of HCCs in the hepatobiliary phase of gadoxetic acid-enhanced MR imaging positively correlated with OATP8 and MRP3 expression levels. Iso- or hyperintense HCCs are associated with a high frequency of a pseudoglandular proliferation pattern and bile plugs at histologic examination, the researchers observed.

Compared with multiphasic 64-section multidetector CT, gadodexate disodium-enhanced MR imaging is a more accurate method for evaluating hepatocellular carcinoma in patients with cirrhosis. In a prospective study of 58 patients who underwent both examinations within 30 days of each other, Di Martino and colleagues found that gadodexate disodium-enhanced MR imaging yielded significantly higher diagnostic accuracy and sensitivity than did 64-section multidetector CT. The method can provide improved diagnostic performance, and because of the lack of ionizing radiation, it can reduce the risk of cumulative radiation exposure in patients with cirrhosis undergoing serial multidetector CT examinations, the researchers concluded.

Wash-in and washout dual-energy xenon ventilation CT of the whole lung is feasible for the simultaneous regional evaluation of structural and ventilation abnormalities both quantitatively and qualitatively in chronic obstructive pulmonary disease. In a study of 32 patients, Park and colleagues found that xenon parameters of the low-attenuating lung in the washout period showed the best inverse correlation with results of pulmonary function testing. The technique may provide useful information about a patient's regional ventilatory status, as well as structural abnormalities, the researchers concluded.

In patients with traumatic knee lesions, a virtual noncalcium technique for dual-energy CT can allow bone marrow space assessment by subtracting calcium from cancellous bone, suggesting that bone bruise lesions are potentially detectable with CT. In a study of 21 patients with acute knee trauma, Pache and colleagues found that the technique yielded sensitivity as high as 86.4% and specificity as high as 95.5%. Despite the potentially significant radiation dose increase, dual-energy CT could serve as a useful tool in the diagnostic workup of traumatic knee lesions, the researchers concluded.

Dynamic evaluation of the small-bowel wall with contrast-enhanced MR imaging may help depict the inflammation state in celiac disease. In a cohort of 135 subjects, Masselli and colleagues found significant differences in the imaging parameters among patients with untreated celiac disease, patients who were on a gluten-free diet for at least 1 year, and control subjects. The researchers noted that there was no significant difference in duodenal wall thickness among the three groups, which suggests that duodenal wall thickening is not related to inflammation.

A single, high-dose in utero exposure to a water-soluble, low-osmolar iodinated contrast medium is unlikely to have a clinically important effect on thyroid function in newborns. In a study of 343 newborns exposed to the iodinated contrast medium iohexol at various stages of gestation, Bourjeily and colleagues found that all newborns had normal thyroxine levels at birth, and only one of 85 newborns tested for thyroid-stimulating hormone (TSH)-born to a mother with multiple drug exposures during pregnancy-had a transient elevation in TSH level at day 2 of life, which normalized 6 days after birth. The results may assuage providers' concerns about how the use of these agents affects thyroid function during pregnancy, the researchers concluded.

In patients with or at risk for knee osteoarthritis, subchondral edema-like lesions in the bone marrow at MR imaging are a predictor of subchondral cyst-like lesions. Crema and colleagues found in a study of 1283 knees of subjects who were participants in the Multicenter Osteoarthritis (MOST) study that subchondral cyst-like lesions developed longitudinally in the same subregion as bone marrow edema-like lesions, even after adjustment for full-thickness cartilage loss. The odds ratio was 12.9. The results support the bone contusion theory of subchondral cyst-like lesion formation, the researchers concluded.