Abbreviated MRI for patients presenting to the emergency department with hip pain.

OBJECTIVE: The objective of our study was to assess the diagnostic performance of two abbreviated hip MRI protocols--coronal STIR images only and coronal STIR with coronal T1-weighted images--as compared with a full hip MRI protocol in patients presenting to the emergency department (ED) with hip pain and negative radiographic findings. MATERIALS AND METHODS: The cohort included 385 patients (277 females, 108 males; mean age, 61 years; age range, 16-99 years) who underwent MRI within 1 month of negative radiographs obtained for ED evaluation of hip pain between January 2000 and March 2009. MR examinations were graded independently by two musculoskeletal fellowship-trained emergency radiologists for detection of fracture, avascular necrosis (AVN), and muscle injury in three subsets: coronal STIR images only; coronal STIR images and coronal T1-weighted images; and the full examination. RESULTS: MRI detected findings suspicious for fracture in 42% (162/385) of patients, for AVN in 9% (33/385), and for muscle injury in 35% (134/385). The sensitivity and specificity of STIR alone in raising concern for fracture was 99% (220/223) for both readers, with small incremental benefits of adding coronal T1-weighted images. For AVN, specificity was 100% (28/28) with STIR alone, but the addition of coronal T1-weighted images provided substantial benefit by increasing sensitivity from 85% (28/33) to 97% (32/33). For muscle injury, sensitivity and specificity exceeded 95% (128/134) for both abbreviated examinations. CONCLUSION: An abbreviated MRI protocol including coronal STIR and coronal T1-weighted images has high sensitivity and specificity for fracture, AVN, and muscle injury in ED patients presenting with hip pain and negative radiographs.

Primary idiopathic chylopericardium.

Primary idiopathic chylopericardium is rare and represents a fraction of all pericardial effusions in the pediatric population. Most cases of chylopericardium occur as a complication of cardiac surgery or after trauma. They may also be caused by tuberculosis, neoplasm, or congenital lymphangiomatosis. Primary idiopathic chylopericardium is a rare disease with unknown etiology. In assessing pediatric patients with an enlarged cardiac silhouette one should be aware of this entity and its presentation. We report two cases of primary idiopathic chylopericardium, one of which at 6 weeks of age is the youngest case to our knowledge so far reported.