Nearly every bone in the body is invested in periosteum. The periosteum is in some ways poorly understood and has been a subject of controversy and debate. This tissue has a major role in bone growth and bone repair and has an impact on the blood supply of bone as well as skeletal muscle. Despite the importance of the periosteum is has received little attention in the literature in recent years.

Purpose:To image cartilage-bone interfaces in naturally occurring and experimentally prepared human cartilage-bone specimens at 3 T by using ultrashort echo time (TE) (UTE) and conventional pulse sequences to (a) determine the appearance of the signal intensity patterns and (b) identify the structures contributing to signal intensity on the UTE MR images. Materials and Methods:This study was exempted by the institutional review board, and informed consent was not required. Five cadaveric (mean age, 86 years 6 4) patellae were imaged by using proton density-weighted fat-suppressed (repetition time msec/TE msec, 2300/34), T1-weighted (700/10), and UTE (300/0.008, 6.6, with or without dual-inversion preparations at inversion time 1 = 135 msec and inversion time 2 = 95 msec) sequences. The UTE images were compared with proton density-weighted fat-suppressed and T1-weighted images and were evaluated by two radiologists. Results:On the UTE MR images, all patellar sections exhibited a high-intensity linear signal near the osteochondral junction, which was not visible on protein density-weighted fat-suppressed or T1-weighted images. In some sections, focal regions of thickened or diminished signal intensity were also found. In the prepared samples, UCC only, CC/bone, and UCC/CC/bone samples exhibited high signal intensity on the UTE images, whereas bone-only samples did not. Conclusion:These results show that the high signal intensity on UTE images of human articular joints originates from the CC and the deepest layer of the UCC, without a defi nite contribution from subchondral bone. UTE sequences may provide a way of evaluating abnormalities at or near the osteochondral junction.q RSNA, 2010

Introduction Liver fibrosis and cirrhosis are late complications in Fontan palliation. Liver biopsy is the gold standard. The goal of this study is to correlate transjugular liver biopsy (TJLB) in the setting of Fontan palliation with noninvasive testing and hemodynamics. Methods Between August 2014 and July 2017, 49 Fontan patients underwent TJLB. All the patients had hemodynamic evaluation, 28 patients had MRE (magnetic resonance elastography) and 40 patients had cardiopulmonary exercise test. Histologic liver fibrosis was quantitated using traditional histologic scoring systems and a modified Ishak congestive hepatic fibrosis score. Results Median age 17.8 years, median time since Fontan 15.2 years. Primary diagnosis and Fontan type were variables, but predominantly LV morphology (30/49), lateral tunnel Fontan (29/49), originally fenestrated (37/49), and 11/49 had a pacemaker. Histologic fibrosis correlated with MRE (R = 0.62, P ≤ .001). Histologic fibrosis and MRE correlated with Fontan pressure (R = 0.38, P = .008 & R = 0.59, P ≤ .001). Morphology of the single ventricle did not correlate with liver fibrosis. The presence of a fenestration resulted in a higher cardiac index (P = .026) but did not resulted in lower liver fibrosis (P = .64). Conclusion Noninvasive tests, such as MRE, may be suitable for longitudinal follow‐up in patients with single ventricle physiology. Our data suggest that there is reasonable correlation of MRE liver stiffness with biopsy scoring systems and Fontan pressures. We demonstrated the feasibility of TJLB in the setting of Fontan palliation and demonstrated its correlation with noninvasive measures particularly MRE. We recommend selective use of TJLB when MRE score is >5 KPa or when there are other clinical signs of cirrhosis.

The growth plates, or physes, are visible on virtually all images obtained in skeletally immature children. The proper function of these growth plates depends on an intricate balance between chondrocyte proliferation, which requires nourishment from the epiphyseal vessels, and chondrocyte death, which requires the integrity of the metaphyseal vessels. Therefore, injury to the growth plate (ie, direct insult) or vascular compromise on either side of the growth plate (ie, indirect insult) can cause growth plate dysfunction. Direct growth plate insults occur most commonly with Salter-Harris fractures, and injuries that allow the transphyseal communication of vessels are at a higher risk for subsequent transphyseal bone bridge formation. Indirect insults lead to different sequelae that are based on whether the epiphyseal blood supply or metaphyseal blood supply is compromised. Epiphyseal osteonecrosis can result in slowed longitudinal bone growth, with possible growth plate closure, and is often accompanied by an abnormal secondary ossification center. In contrast, the disruption of metaphyseal blood supply alters endochondral ossification and allows the persistence of chondrocytes within the metaphysis, which appear as focal or diffuse growth plate widening. Imaging remains critical for detecting acute injuries and identifying subsequent growth disturbances. Depending on the imaging findings and patient factors, these growth disturbances may be amenable to conservative or surgical treatment. Therefore, an understanding of the anatomy and physiologic features of the normal growth plate and the associated pathophysiologic conditions can increase diagnostic accuracy, enable radiologists to anticipate future growth disturbances, and ensure optimal imaging, with the ultimate goal of timely and appropriate intervention. RSNA, 2017.

A tailored approach to MR arthrography may be a useful way to isolate expected pathology in the shoulder and limit confounding findings related to the performance of the procedure.