Kirsten Ecklund

Bone marrow changes in adolescent girls with anorexia nervosa

Early osteoporosis is common among adolescent girls with anorexia nervosa (AN) and may result from premature conversion of red (RM) to yellow bone marrow. We performed right knee magnetic resonance imaging (MRI) on a 1.0 T extremity scanner in 20 patients and 20 healthy controls, aged 16.2 ± 1.6 years (mean ± SD). Coronal T1‐weighted (T1W) images and T1 maps were generated from T1 relaxometry images. Blinded radiologists visually assessed RM in the distal femoral and proximal tibial metaphyses in T1W images using a scale of signal intensity from 0 (homogeneous hyperintensity, no RM) to 4 (all dark, complete RM). Subjects with AN exhibited nearly twofold lower metaphyseal RM scores in both the femur (0.64 versus 1.22, p = .03) and tibia (0.54 versus 0.96, p = .08). In relaxometric measurements of four selected regions (femur and tibia amd epiphysis and metaphysis), subjects with AN showed higher mean epiphyseal but lower metaphyseal T1. The net AN‐control difference between epiphysis and metaphysis was 70 ms in the femur (+31 versus −35 ms, p = .02) and of smaller magnitude in the tibia. In relaxometry data from the full width of the femur adjacent to the growth plate, AN subjects showed mean T1 consistently lower than in controls by 30 to 50 ms in virtually every part of the sampling region. These findings suggest that adolescents with AN exhibit premature conversion of hematopoietic to fat cells in the marrow of the peripheral skeleton potentially owing to adipocyte over osteoblast differentiation in the mesenchymal stem cell pool.

IMAGING OF GROWTH DISTRUBANCE IN CHILDREN

Disturbance of skeletal growth occurs often in children and results in considerable lifelong disability. When acquired, it is most frequently post-traumatic but may also be caused by other insults, such as infection, ischemia, tumoral lesions, and radiation. 15 The complications of growth disturbance (leg length discrepancy, angular deformity, and altered joint mechanics) cause significant morbidity. MR imaging, with its ability to depict the cartilaginous structures of developing bones, has become the modality of choice for evaluating children with growth disorders and directing surgical management. An understanding of normal enchondral ossification and the anatomy of the ends of growing bones is essential for appreciation of the MR imaging findings in such patients.

The Bridge-Enhanced Anterior Cruciate Ligament Repair (BEAR) Procedure An Early Feasibility Cohort Study

Background: This study assessed the safety of the newly developed bridge-enhanced anterior cruciate ligament (ACL) repair (BEAR), which involves suture repair of the ligament combined with a bioactive scaffold to bridge the gap between the torn ligament ends. As the intra-articular environment is complex in its response to implanted materials, this study was designed to determine whether there would be a significant rate of adverse reaction to the implanted scaffold. Hypothesis: The primary hypothesis was that the implanted scaffold would not result in a deep joint infection (arthrocentesis with positive culture) or significant inflammation (clinical symptoms justifying arthrocentesis but negative culture). The secondary hypotheses were that patients treated with BEAR would have early postoperative outcomes that were similar to patients treated with ACL reconstruction with an autologous hamstring graft. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 20 patients were enrolled in this nonrandomized, first-in-human study. Ten patients received BEAR treatment and 10 received a hamstring autograft ACL reconstruction. The BEAR procedure was performed by augmenting a suture repair with a proprietary scaffold, the BEAR scaffold, placed in between the torn ends of the ACL at the time of suture repair. The BEAR scaffold is to our knowledge the only device that fills the gap between the torn ligament ends to have current Investigational Device Exemption approval from the Food and Drug Administration. Ten milliliters of autologous whole blood were added to the scaffold prior to wound closure. Outcomes were assessed at 3 months postoperatively. The outcomes measures included postoperative pain, muscle atrophy, loss of joint range of motion, and implant failure (designated by an International Knee Documentation Committee grade C or D Lachman test and/or an absence of continuous ACL tissue on magnetic resonance images). Results: There were no joint infections or signs of significant inflammation in either group. There were no differences between groups in effusion or pain, and no failures by Lachman examination criteria (BEAR, 8 grade A and 2 grade B; ACL reconstruction, 10 grade A). Magnetic resonance images from all of the BEAR and ACL-reconstructed patients demonstrated a continuous ACL or intact graft. In addition, hamstring strength at 3 months was significantly better in the BEAR group than in the hamstring autograft group (mean ± SD: 77.9% ± 14.6% vs 55.9% ± 7.8% of the contralateral side; P < .001). Conclusion: The results of this study suggest that the BEAR procedure may have a rate of adverse reactions low enough to warrant a study of efficacy in a larger group of patients.

Mechanisms of injury to white matter adjacent to a large intraventricular hemorrhage in the preterm brain.

The purpose of this article is to investigate the hyperechoic lesion seen adjacent to a lateral ventricle that contains blood but is not distended. The literature on ependymal barrier dysfunction was reviewed in search of mechanisms of injury to the white matter adjacent to an intraventricular hemorrhage. The clinical literature on the clinical diagnosis of periventricular hemorrhagic infarction was also reviewed to find out how frequently this diagnosis was made. Support was found for the possibility that the ventricular wall does not always function as an efficient barrier, allowing ventricular contents to gain access to the white matter where they cause damage. Hemorrhagic infarction may not be the only or the most frequent mechanism of white matter damage adjacent to a large intraventricular hemorrhage.

Rickets on MR images

Background. The pathologic changes at the physis in patients with rickets have been well demonstrated histologically. Radiographs can depict only the associated osseous abnormalities. Patients and methods. We report two children in whom MR imaging demonstrated rachitic changes in the physeal cartilage beyond the well-recognized bony features. Results. The striking appearance of the physes and the physes of the secondary ossification centers confirm that MR imaging can successfully evaluate the cartilaginous structures of the developing skeleton. Conclusion. Though MR imaging is clearly unnecessary for the diagnosis of rickets, it is important that the typical features are not misinterpreted as other pathology.

Reader Variability in the Use of Diagnostic Terms to Describe White Matter Lesions Seen on Cranial Scans of Severely Premature Infants: The ELGAN Study

To evaluate reader variability of white matter lesions seen on cranial sonographic scans of extreme low gestational age neonates (ELGANs).

Response Evaluation Criteria in Solid Tumors (RECIST) following neoadjuvant chemotherapy in osteosarcoma

In osteosarcoma, patient survival has not changed in over 30 years. Multiple phase II trials have been conducted in osteosarcoma using the Response Evaluation Criteria in Solid Tumors (RECIST) as a primary endpoint; however, none of these have revealed new treatment strategies. We investigated RECIST in newly diagnosed patients who received neoadjuvant chemotherapy proven to be beneficial.

MR Imaging of the Pediatric Foot and Ankle: What Does Normal Look Like?

MR imaging is ideally suited for characterization of the soft tissue, cartilaginous, and osseous structures of the pediatric ankle. An understanding of the normal MR imaging appearance associated with the dynamic skeletal maturation process will prevent overdiagnosis and unnecessary treatment. In this article, we review the normal MR imaging appearance of the growing ankle as well as several disease processes unique to the pediatric population.

MR Imaging in a case of severe anorexia nervosa: the ‘flip-flop’ effect

We report an MR imaging phenomenon that can lead to misinterpretation. The unique appearance of the soft tissues and bone marrow in a 19-year-old severely malnourished woman with anorexia nervosa raised concerns about technical failure or systemic pathology. Due to extreme fat depletion, the T1-weighted images appeared to be fat-suppressed and the fat-suppressed fluid-sensitive images appeared to be non-fat-suppressed (“flip-flopped”). Failure to recognize the influence of a patient’s overall nutritional status on MR images may cause confusion and misdiagnosis.

Radiologic-Pathologic Conference of Children's Hospital Boston: Abdominal mass in a prepubertal girl

Abstract A 9-year old girl with a large abdominal mass is presented. The clinical history, CT images, histological dindings, current classification and therapy are discussed.