https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(11)60243-2.pdf

Osteoarthritis: an update with relevance for clinical practice

Methods: Risk models based on the National Research Council’s “Biological Effects of Ionizing Radiation” report and organ-specific radiation doses derived from a national survey were used to estimate age-specific cancer risks for each scan type. These models were combined with age- and sex-specific scan frequencies for the US in 2007 obtained from survey and insurance claims data. We estimated the mean number of radiationrelatedincidentcancerswith95%uncertaintylimits(UL) using Monte Carlo simulations. Results:Overall,weestimatedthatapproximately29000 (95% UL, 15000-45000) future cancers could be related to CT scans performed in the US in 2007. The largest contributions were from scans of the abdomen and pelvis (n=14 000) (95% UL, 6900-25 000), chest (n=4100) (95% UL, 1900-8100), and head (n=4000) (95% UL, 1100-8700), as well as from chest CT angiography (n=2700) (95% UL, 1300-5000). One-third of the projectedcancerswereduetoscansperformedattheages of 35 to 54 years compared with 15% due to scans performed at ages younger than 18 years, and 66% were in females.

https://jamanetwork.com/journals/jamainternalmedicine/articlepdf/415368/ioi90109_2071_2077.pdf

Projected cancer risks from computed tomographic scans performed in the United States in 2007.

Superparamagnetic nanoparticles for biomedical applications: Possibilities and limitations of a new drug delivery system

The Brush Foundation studies on human growth and development, begun in 1931 and terminated in 1942, have been intensively reviewed and studied by Dr Greulich and Miss Pyle in the formulation of this Radiographic Atlas of Skeletal Development of the Hand and Wrist Serial radiographs of from 2 to 20 hand-films made at successive examinations of each of 1000 boys and girls made up the radiographic material Standards were selected that were judged to be the most representative of the central tendency or anatomic mode of each chronologic age group from birth through 18 years

Radiographic Atlas of Skeletal Development of the Hand and Wrist

eMedicine创建于1996年，由近万名临床医师作为作者或编辑参与此临床医学知识库的建设，其中编辑均是来自美国哈佛、耶鲁、斯坦福、芝加哥、德克萨斯、加州大学等各分校医学院的教授或副教授。

eMedicine

Biochemical and histologic data have validated the technique of delayed gadolinium-enhanced MRI, in which the T(1) values of cartilage after penetration of Gd(DTPA)2-allow assessment of the glycosaminoglycan (GAG) component of articular cartilage. This work describes the factors that have been found to be important for the practical implementation of the technique: 1) Exercise immediately after intravenous contrast administration was necessary for effective penetration of the contrast into the articular cartilage; 2) double-dose contrast was better than single-dose; 3) after contrast administration, a time window of 30-90 min for the hip, and 2-3 hr for all compartments of the knee proved to be appropriate for assessing articular cartilage; and 4) in some cases of hypointensities in the subchondral patellar bone, decreased penetration of the contrast agent into cartilage from bone was found. With the protocol described, ROIs on T(1) images were reproducible within 15% on two separate imaging sessions, and initial clinical studies demonstrated the possible applications of the technique. Magn Reson Med 45:36-41, 2001.

Protocol issues for delayed Gd(DTPA)(2-)-enhanced MRI (dGEMRIC) for clinical evaluation of articular cartilage.

Ninety-four patients who had brachial plexus birth palsy were entered into a prospective study to evaluate the association between persistent palsy, age-related musculoskeletal deformity, and functional limitations. Of these patients, forty-two had either computerized tomography or magnetic resonance imaging to assess the presence and degree of incongruity of the glenohumeral joint, deformity of the humeral head, and hypoplasia of the glenoid as part of the preoperative planning for a reconstructive operation. Functional ability was rated with use of the classification of Mallet, on a scale of 1 to 5. The mean glenoscapular angle (the degree of retroversion of the glenoid) on the affected side was -25.7 degrees compared with -5.5 degrees on the unaffected side. Twenty-six (62 per cent) of the forty-two shoulders had evidence of posterior subluxation of the humeral head, with a mean of only 25 per cent (range, 0 to 50 per cent) of the head being intersected by the scapular line. Progressive deformity was found with increasing age (p < 0.001). The natural history of untreated brachial plexus birth palsy with residual weakness is progressive glenohumeral deformity due to persistent muscle imbalance. The status of the glenohumeral joint must be addressed when the choice between tendon transfer and humeral derotation osteotomy for reconstruction of the shoulder is considered for these patients.

Glenohumeral Deformity Secondary to Brachial Plexus Birth Palsy

The Image Gently campaign: working together to change practice.

The neurofibromatoses are a diverse group of genetic conditions that share a predisposition to the development of tumors of the nerve sheath. Schwannomatosis is a recently recognized third major form of neurofibromatosis (NF) that causes multiple schwannomas without vestibular tumors diagnostic of NF2. Patients with schwannomatosis represent 2.4 to 5% of all patients requiring schwannoma resection and approximately one third of patients with schwannomatosis have anatomically localized disease with tumors limited to a single limb or segment of spine. Epidemiologic studies suggest that schwannomatosis is as common as NF2, but that familial occurrence is inexplicably rare. Patients with schwannomatosis overwhelmingly present with pain, and pain remains the primary clinical problem and indication for surgery. Diagnostic criteria for schwannomatosis are needed for both clinicians and researchers, but final diagnostic certainly will await the identification of the schwannomatosis locus itself.

Diagnostic criteria for schwannomatosis

Background: The efficacy of surgical and medical treatment of osteoarthritis is difficult to assess because of the lack of a noninvasive, sensitive measure of cartilage integrity. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) was designed to specifically examine glycosaminoglycan changes in articular cartilage that occur during the development of osteoarthritis. Our primary goal was to compare this technique with measurement of the joint space width on conventional radiographs in patients with hip dysplasia. We performed this comparison by assessing the correlation between the findings of each technique and clinically important factors such as pain, severity of dysplasia, and age.

Methods: Sixty-eight hips in forty-three patients were included in the study. Clinical symptoms were assessed with use of the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) questionnaire. The width of the joint space as well as the lateral center-edge angle of Wiberg (as a measure of the severity of the dysplasia) was measured on standard standing radiographs. Magnetic resonance imaging maps of glycosaminoglycan distribution were made with T1-calculated images after administration of gadopentetate 2− (Gd-DTPA 2− ). The dGEMRIC index was calculated as the average of the T1 values for the acetabular and femoral head cartilages.

Results: The dGEMRIC index correlated with both pain (rs = −0.50, p < 0.0001) and the lateral center-edge angle (rs = 0.52, p < 0.0001), whereas the joint space width did not correlate with either, with the numbers available. There was a correlation between the dGEMRIC index and pain whether or not a labral tear was present. The dGEMRIC index was significantly different (p < 0.0001) among three groups of hips classified according to whether they had mild, moderate, or severe dysplasia, whereas the joint space width did not differ significantly among these three groups. There was no significant correlation between age and any of the other parameters.

Conclusions: We demonstrated that, in patients with hip dysplasia, the dGEMRIC index—a measure of the biochemical integrity of cartilage—correlates with pain and the severity of the dysplasia and is significantly different among groups of hips with mild, moderate, and severe dysplasia, suggesting that it may be a sensitive measure of early osteoarthritis. Additional studies are needed to determine whether dGEMRIC can be used to predict disease progression in different situations and/or demonstrate responses to therapeutic interventions.

Diego Jaramillo

Papers

Protocol issues for delayed Gd(DTPA)(2-)-enhanced MRI (dGEMRIC) for clinical evaluation of articular cartilage.

Glenohumeral Deformity Secondary to Brachial Plexus Birth Palsy

The Image Gently campaign: working together to change practice.

Diagnostic criteria for schwannomatosis

Assessment of early osteoarthritis in hip dysplasia with delayed gadolinium-enhanced magnetic resonance imaging of cartilage.