Intra-articular solitary fibrous tumor of the knee.

A rare case of intra-articular solitary fibrous tumor of the knee in an 84-year-old man is presented. This case report illustrates that solitary fibrous tumor should be included in the extended differential diagnosis of an intra-articular soft tissue mass.

No More HF: Teflon-Assisted Ultrafast Removal of Silica to Generate High-Surface-Area Mesostructured Carbon for Enhanced CO2 Capture and Supercapacitor Performance.

An innovative technique to obtain high-surface-area mesostructured carbon (2545 m(2) g(-1)) with significant microporosity uses Teflon as the silica template removal agent. This method not only shortens synthesis time by combining silica removal and carbonization in a single step, but also assists in ultrafast removal of the template (in 10 min) with complete elimination of toxic HF usage. The obtained carbon material (JNC-1) displays excellent CO2 capture ability (ca. 26.2 wt % at 0 °C under 0.88 bar CO2 pressure), which is twice that of CMK-3 obtained by the HF etching method (13.0 wt %). JNC-1 demonstrated higher H2 adsorption capacity (2.8 wt %) compared to CMK-3 (1.2 wt %) at -196 °C under 1.0 bar H2 pressure. The bimodal pore architecture of JNC-1 led to superior supercapacitor performance, with a specific capacitance of 292 F g(-1) and 182 F g(-1) at a drain rate of 1 A g(-1) and 50 A g(-1) , respectively, in 1 m H2 SO4 compared to CMK-3 and activated carbon.

Diffusion tensor imaging of the normal foot at 3 T.

OBJECTIVE: The objective of this study was to establish normative diffusion tensor imaging (DTI) eigenvalues (λ1,λ2,λ3), apparent diffusion coefficient, and fractional anisotropy in asymptomatic foot muscles. METHODS: Ten healthy adults (mean [SD], 25.9 [4.3] years) were examined using a 3-T magnetic resonance imaging scanner. Diffusion tensor imaging indices were evaluated in 5 muscles in the foot: quadratus plantae, abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, and abductor digiti minimi. Signal-to-noise ratio was also measured for each muscle. RESULTS: In the various foot muscles, λ1 ranged from 1.88 × 10 to 2.14 × 10 mm/s, λ2 ranged from 1.39 × 10 to 1.48 × 10 mm/s, and λ3 ranged from 0.91 × 10 to 1.27 × 10 mm/s; apparent diffusion coefficient ranged from 1.48 × 10 to 1.55 × 10 mm/s; and fractional anisotropy ranged from 0.21 to 0.40. Statistical differences were seen in some eigenvalues between muscle pairs. Mean signal-to-noise ranged from 47.5 to 69.1 in the various muscles examined. CONCLUSIONS: Assessment of anisotropy of water diffusion in foot muscles was feasible using DTI. The measured DTI metrics in the foot were similar to those in calf and thigh skeletal muscles.

Femoroacetabular impingement in elite ice hockey players.

PURPOSE: The purpose of this study is to evaluate the presence of clinical and radiological femoroacetabular impingement (FAI) in elite ice hockey players and compare it to a control group of non-athletes. METHODS: Forty participants (20 non-athletes and 20 elite ice hockey athletes) underwent an evaluation of their hip joint, including assessment of range of motion and special provocative impingement tests. Two musculoskeletal radiologists assessed MRIs completed on each participant for radiological findings associated with FAI, including alpha angle, acetabular version angle, acetabular depth, and/or a lateral centre edge angle, and findings of labral and cartilage degeneration. A comparative analysis of the clinical and radiological findings was subsequently completed. RESULTS: There was a significant difference in the radiological CAM impingement measured by mean alpha angle between both groups (non-athletes: 43.2 degrees, SD 9.7; and athletes: 54.2 degrees, SD 12 (p = 0.003)). There were no statistically significant differences between the groups upon evaluating PINCER impingement. There were no statistically significant differences in clinical examination findings between both groups. CONCLUSION: MRI evidence suggests that CAM impingement is more common in the elite ice hockey athlete in comparison with non-athletes. However, as this is a pilot study examining findings in asymptomatic individuals, there is a need for a longitudinal prospective cohort study. In keeping with this, sufficient, long-term follow-up is required to assess at what point, if any, these subjects with radiological findings become symptomatic.

MR imaging of the spine and sacroiliac joints for spondyloarthritis: influence on clinical diagnostic confidence and patient management.

PURPOSE: To quantify the effect of magnetic resonance (MR) imaging of the spine and sacroiliac joints on clinical diagnostic confidence and to determine if MR imaging affects treatment of patients with axial spondyloarthritis. MATERIALS AND METHODS: This prospective observational study was approved by the research ethics board and included 55 consecutive patients referred by three rheumatologists for MR imaging of the spine and sacroiliac joints. Measures of diagnostic confidence for clinical features (inflammatory back pain, mechanical back pain, muscular back pain, radicular back pain, spondylitis, sacroiliitis, and other) and overall diagnoses were made by using a Likert scale both before and after MR imaging. Proposed treatment was similarly recorded before and after MR imaging interpretation. The McNemar test was performed to determine the change in diagnostic confidence and consequent effect on patient treatment. RESULTS: Diagnostic confidence for specific clinical features improved significantly after MR imaging for inflammatory back pain (14% vs 76%, before vs after; P < .001), mechanical back pain (4% vs 49%, P < .001), spondylitis (7% vs 76%, P < .001) and sacroiliitis (9% vs 87%, P < .001). Confidence for overall diagnoses also improved significantly after MR imaging for ankylosing spondylitis (29% vs 80%, P < .001), undifferentiated spondyloarthritis (58% vs 93%, P < .001) and osteoarthritis (29% vs 64%, P < .001). Of the 23 patients for whom tumor necrosis factor-α inhibitor (TNFi) therapy was recommended before MR imaging, 12 (52%) were prescribed TNFi therapy after MR imaging. Of the 32 patients for whom TNFi therapy was not recommended before MR imaging, 10 (31%) patients were prescribed TNFi therapy after MR imaging. Overall, 22 (40%) patients had a change in treatment recommendation regarding TNFi therapy after MR imaging. CONCLUSION: MR imaging of the spine and sacroiliac joints significantly influences the diagnostic confidence of rheumatologists regarding clinical features and overall diagnoses of axial spondyloarthritis, and consequently significantly affects treatment plans.

Quantitative DTI assessment in human lumbar stabilization muscles at 3 T.

OBJECTIVES: To characterize diffusion tensor imaging (DTI) tensor eigenvalues (λ1, λ2, λ3), fractional anisotropy, mean diffusivity, and radial diffusivity in healthy lumbar musculature. METHODS: Seventeen healthy subjects (10 men, 7 women; mean age, 28 ± 7 years) were scanned using a 3.0-T magnetic resonance imaging. Axial DTI was performed using 15 diffusion directions (b = 400 mm/s) at the L4 level. Oswestry Low Back Pain and Godin Physical Activity questionnaires were administered to rule out underlying lower back problems. RESULTS: Skeletal muscle DTI metrics were similar to those previously published. All measurements showed low coefficients of variation, except for quadratus lumborum. Laterality was not significant. Significant sex differences were observed in the quadratus lumborum (P < 0.05). Significant correlations were found between subjects' weight and body mass index with fractional anisotropy and λ1 of the multifidus muscles. CONCLUSIONS: The DTI metrics in paraspinal muscles can be reliably measured and are influenced by body mass index and weight but not by age or physical activity.

Lateral epicondylitis and beyond: imaging of lateral elbow pain with clinical-radiologic correlation.

The diagnosis of lateral epicondylitis is often straightforward and can be made on the basis of clinical findings. However, radiological assessment is valuable where the clinical picture is less clear or where symptoms are refractory to treatment. Demographics, aspects of clinical history, or certain physical signs may suggest an alternate diagnosis. Knowledge of the typical clinical presentation and imaging findings of lateral epicondylitis, in addition to other potential causes of lateral elbow pain, is necessary. These include entrapment of the posterior interosseous and lateral antebrachial cutaneous nerves, posterolateral rotatory instability, posterolateral plica syndrome, Panner's disease, osteochondritis dissecans of the capitellum, radiocapitellar overload syndrome, occult fractures and chondral-osseous impaction injuries, and radiocapitellar arthritis. Knowledge of these potential masquerades of lateral epicondylitis and their characteristic clinical and imaging features is essential for accurate diagnosis. The goal of this review is to provide an approach to the imaging of lateral elbow pain, discussing the relevant anatomy, various causes, and discriminating factors, which will allow for an accurate diagnosis.

Diagnostic Test Accuracy of Ultrasonography vs Computed Tomography for Papillary Thyroid Cancer Cervical Lymph Node Metastasis: A Systematic Review and Meta-analysis.

Importance: The use of ultrasonography (US) vs cross-sectional imaging for preoperative evaluation of papillary thyroid cancer is debated. Objective: To compare thyroid US and computed tomography (CT) in the preoperative evaluation of papillary thyroid cancer for cervical lymph node metastasis (CLNM), as well as extrathyroidal disease extension. Data Sources: MEDLINE and Embase were searched from January 1, 2000, to July 18, 2020. Study Selection: Studies reporting on the diagnostic accuracy of US and/or CT in individuals with treatment-naive papillary thyroid cancer for CLNM and/or extrathyroidal disease extension were included. The reference standard was defined as histopathology/cytology or imaging follow-up. Independent title and abstract review (2515 studies) followed by full-text review (145 studies) was completed by multiple investigators. Data Extraction and Synthesis: PRISMA guidelines were followed. Methodologic and diagnostic accuracy data were abstracted independently by multiple investigators. Risk of bias assessment was conducted using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool independently and in duplicate. Bivariate random-effects model meta-analysis and multivariable meta-regression modeling was used. Main Outcomes and Measures: Diagnostic test accuracy of US and CT of the neck for lateral and central compartment CLNM, as well as for extrathyroidal disease extension, determined prior to study commencement. Results: A total of 47 studies encompassing 31 942 observations for thyroid cancer (12 771 with CLNM; 1747 with extrathyroidal thyroid extension) were included; 21 and 26 studies were at low and high risk for bias, respectively. Based on comparative design studies, US and CT demonstrated no significant difference in sensitivity (73% [95% CI, 64%-80%] and 77% [95% CI, 67%-85%], respectively; P = .11) or specificity (89% [95% CI, 80%-94%] and 88% [95% CI, 79%-94%], respectively; P = .79) for lateral compartment CLNM. For central compartment metastasis, sensitivity was higher in CT (39% [95% CI, 27%-52%]) vs US (28% [95% CI, 21%-36%]; P = .004), while specificity was higher in US (95% [95% CI, 92%-98%]) vs CT (87% [95% CI, 77%-93%]; P < .001). Ultrasonography demonstrated a sensitivity of 91% (95% CI, 81%-96%) and specificity of 47% (95% CI, 35%-60%) for extrathyroidal extension. Conclusions and Relevance: The findings of this systematic review and meta-analysis suggest that further study is warranted of the role of CT for papillary thyroid cancer staging, possibly as an adjunct to US.

MR imaging of skeletal soft tissue infection: utility of diffusion-weighted imaging in detecting abscess formation.

PURPOSE: Our objectives were to assess if diffusion-weighted imaging (DWI) can help identify abscess formation in the setting of soft tissue infection and to assess whether abscess formation can be diagnosed confidently with a combination of DWI and other unenhanced sequences. METHODS: Eight cases of soft tissue infection imaged with MRI including DWI were retrospectively reviewed. RESULTS: Two male and six female patients were studied (age range 23-50 years). Unenhanced MRI including DWI was performed in all patients. Post-contrast images were obtained in seven patients. All patients had clinically or surgically confirmed abscesses. Abscesses demonstrated restricted diffusion. DWI in conjunction with other unenhanced imaging showed similar confidence levels as post-contrast images in diagnosing abscess formation in four cases. In two cases, although the combined use of DWI and other unenhanced imaging yielded the same confidence levels as post-contrast imaging, DWI was more definitive for demonstrating abscess formation. In one case, post-contrast images had a better confidence for suggesting abscess. In one case, DWI helped detected the abscess, where gadolinium could not be administered because of a contraindication. CONCLUSION: This preliminary study suggests that DWI is a useful adjunct in the diagnosis of skeletal soft tissue abscesses.

Intra-articular nodular fasciitis of the shoulder: a case report and review of the literature.

Nodular fasciitis is a benign proliferation of myofibroblasts usually arising adjacent to the fascia. In this report, we describe a rare case in which nodular fasciitis occurred in an intra-articular location in the shoulder of a 26-year-old man. The mass developed in the subscapularis recess of the shoulder and histological evaluation showed a myofibroblastic proliferation. MRI findings of intra-articular nodular fasciitis are discussed along with a review of previous reports.

Medial ankle and heel: ultrasound evaluation and sonographic appearances of conditions causing symptoms.

The complex anatomy of the medial ankle and hindfoot can make clinical assessment of medial ankle and heel pain challenging. Ultrasound is an accessible, relatively inexpensive modality, and modern high-resolution probes allow eloquent demonstration of the main structures that are implicated as potential causes of medial ankle pain. In this work we review highlights the clinically relevant anatomy and normal sonographic appearances of structures around the medial ankle and heel and discuss key techniques to allow optimal ultrasound assessment. The conditions that cause medial-sided ankle and heel symptoms are discussed with their characteristic sonographic appearances.

Stenotrophomonas maltophilia as a rare cause of meningitis and ventriculoperitoneal shunt infection.

Stenotrophomonas maltophilia is an extremely rare pathogen responsible for ventriculoperitoneal shunt infection and meningitis. This young female patient with history of multiple shunt revisions in the past, came to us with shunt dysfunction and exposure of the ventriculoperitoneal shunt tube in the neck. The abdominal end of the shunt tube was seen migrating into the bowel during shunt revision. The cerebrospinal fluid analysis showed evidence of Stenotrophomonas maltophilia growth. This is the first reported case of Stenotrophomonas maltophilia meningitis associated with ventriculoperitoneal shunt migration into the bowel.

Sonography of the anterior oblique ligament of the trapeziometacarpal joint: a study of cadavers and asymptomatic volunteers.

OBJECTIVE: The purpose of this study was to evaluate the ability of ultrasound to identify and characterize the anterior oblique ligament of the thumb in cadavers and asymptomatic volunteers. SUBJECTS AND METHODS: The anterior oblique ligaments of four cadaveric hands were imaged with a high-resolution transducer. The ligaments were then injected with 0.1% methylene blue using ultrasound guidance. To confirm identification of the ligament, the base of the thumb was immediately dissected, revealing the exact location of the dye. The bilateral ligaments in 40 asymptomatic adult volunteers were imaged. RESULTS: Surgical dissection confirmed injection of methylene blue into all cadaveric ligaments. The proximal attachment of the anterior oblique ligament was well defined in all the hands, and the distal attachment was well defined in 94% of the hands. The mean thickness of the anterior oblique ligament at the metacarpal attachment (0.7 mm), midportion (0.98 mm), and trapezial attachment (0.65 mm) did not differ significantly with respect to sex, right and left side, or hand dominance and was weakly correlated with weight, height, body mass index, and age. The length of the ligament was statistically significantly different between the dominant (10.6 mm) and nondominant (9.6 mm) hands. The volar metacarpal translation with palmar abduction stress did not differ significantly between the dominant (0.7 mm) and nondominant (0.8 mm) hands. There was no association between the degree of translation and the biologic characteristics (weight, height, body mass index, and age). CONCLUSION: High-resolution ultrasound can be used to identify and measure the thickness of the anterior oblique ligament. Dynamic ultrasound imaging can depict volar translation of the metacarpal, which may facilitate diagnosis of ligamentous injury.

Multimodality imaging of peripheral neuropathies of the upper limb and brachial plexus.

The peripheral nerves of the upper limb are affected by a number of entrapment and compression neuropathies. These discrete syndromes involve the brachial plexus as well as the musculocutaneous, axillary, suprascapular, ulnar, radial, and median nerves. Clinical examination and electrophysiologic studies are the traditional mainstay of diagnostic work-up; however, ultrasonography and magnetic resonance imaging provide spatial information regarding the affected nerve and its surroundings, often assisting in narrowing the differential diagnosis and guiding treatment. Imaging is particularly valuable in complex cases with discrepant nerve function test results. Familiarity with the clinical features of various peripheral neuropathies of the upper extremity, the relevant anatomy, and the most common sites and causes of nerve entrapment assists in diagnosis and treatment.

MR arthrographic assessment of suspected posteroinferior labral lesions using flexion, adduction, and internal rotation positioning of the arm: preliminary experience.

OBJECTIVE: Imaging the shoulder in the position of flexion, adduction, and internal rotation (FADIR) may be useful in characterizing lesions of the posteroinferior labrum. The purpose of this preliminary study is to illustrate the diagnostic utility of FADIR positioning in the assessment and characterization of posteroinferior labral tears. MATERIALS AND METHODS: In the FADIR position, the arm is placed across the chest, with the hand on the contralateral shoulder and palm facing outwards. FADIR positioning was performed if there was a subtle or equivocal abnormality of the posteroinferior labrum on conventional MR arthrography sequences. A retrospective review of the charts of 9 people who were imaged using FADIR positioning in addition to routine MR arthrographic sequences of the shoulder was performed. The review included the indication for the study, documentation of presence of clinical posterior instability, and surgical correlation, where available. RESULTS: In all 9 patients, FADIR positioning helped confirm, exclude, or better characterize a posteroinferior labral abnormality by increasing the diagnostic confidence. CONCLUSION: Flexion, adduction, and internal rotation positioning appears to be a useful adjunct in evaluating patients with equivocal or subtle posteroinferior labral abnormalities on conventional MR arthrography sequences.

Arm Numbness at 45 Degrees Abduction: A Case Report of Thoracic Outlet Syndrome After Brachial Neuritis.

OBJECTIVE: To describe a case of nerve kinking correlating with surgical findings in neurogenic thoracic outlet syndrome in a patient with history of brachial neuritis. Thoracic outlet syndrome and brachial neuritis are briefly reviewed. CASE REPORT: A 32-year-old woman with a history of bilateral brachial neuritis presented with paraesthesias in her hand when abducting her shoulder to 45° or higher. A kink in the superior trunk of the brachial plexus, as well as asymmetrically narrowed costoclavicular space, was found on magnetic resonance imaging with the shoulder abducted. Conservative measures failed, leading to partial anterior scalenectomy and neurolysis, which led to improvement in her symptoms. CONCLUSION: Anatomical variations in combination with biomechanical changes after brachial neuritis can be associated with neurogenic thoracic outlet syndrome.

Sonography of the lateral ulnar collateral ligament of the elbow: study of cadavers and healthy volunteers.

OBJECTIVE: The purpose of this study was to assess the utility of high-resolution sonography in identification and characterization of the size and echogenicity of the lateral ulnar collateral ligament of the elbow in cadavers and healthy volunteers. SUBJECTS AND METHODS: The lateral ulnar collateral ligaments of four cadaveric elbows were imaged with a high-resolution linear-array ultrasound transducer. On localization, the ligaments were injected with 0.1% methylene blue under sonographic guidance. For confirmation of identification of the ligaments, the elbows were immediately dissected to reveal the exact location of the stain. The ligaments of both elbows of 35 healthy adult volunteers were imaged. RESULTS: Surgical dissection confirmed injection of methylene blue into all four cadaveric ligaments. The lateral ulnar collateral ligament was identified bilaterally over the radial head in all 35 volunteers. The mean thickness of the ligament at this point was 1.2 mm in women and men. The proximal attachment of the ligament to the humerus was well visualized bilaterally in 94.3% of volunteers. The mean thickness at this point was 1.7 mm in women and 1.6 mm in men. The distal attachment on the ulna was well visualized in 90% of elbows. The ligament was hyperechoic in relation to muscle in all volunteers. Differences in ligament measurements with regard to sex and hand dominance were not significant. Ligament thickness correlated weakly with volunteer weight, height, body mass index, and age. CONCLUSION: High-resolution ultrasound imaging is accurate for identification and measurement of normal lateral ulnar collateral ligaments. Therefore, ultrasound may prove valuable in assessment of abnormal lateral ulnar collateral ligaments.

Ultrasound of the hands and feet for rheumatological disorders: influence on clinical diagnostic confidence and patient management.

PURPOSE: The purpose of the study was to quantify the impact that ultrasound (US) of the hands and feet has on the rheumatologists' diagnostic confidence and on patient management. MATERIALS AND METHODS: There were 62 consecutive referrals from two rheumatologists for US of the hands and/or feet for this prospective controlled observational study. Measurements of diagnostic confidence for both specific clinical findings as well as overall diagnosis using a Likert scale were made both before and after the US examination in each case. Proposed management was also recorded before US and then with the benefit of the US result. McNemar's test was performed to determine differences in diagnostic certainty and proposed management before and after US. RESULTS: The physician certainty for specific clinical findings increased significantly following US for synovitis (9.7 vs 38.7%), tenosynovitis (9.7 vs 46.8%), erosions (1.6 vs 58.1%), enthesitis (50.0 vs 83.9%) and other (53.2 vs 77.4%). The physician certainty for overall diagnosis increased significantly for seronegative arthritis (46.8 vs 61.3%), inflammatory osteoarthritis (46.8 vs 87.1%), and primary osteoarthritis (46.8 vs 73.0%). A total of 88.7% of patients had disease-modifying antirheumatic drugs as a proposed management option before US vs 48.4% after US. Before US, 4.8% of patients had non-steroidal anti-inflammatory drug as a proposed management option versus 45.2% after US. CONCLUSION: Ultrasound of the hands and/or feet significantly influenced the rheumatologists' diagnostic confidence in specific clinical findings and management plans.

Lung cancer associated with cystic airspaces: Characteristic morphological features on CT in a series of 11 cases.

PURPOSE: To familiarize the reader with the entity 'lung cancer associated with cystic airspaces' (LC-CAS) and create an awareness about the potential for slow progressive development of cancer within these nonaggressive appearing cystic airspaces (CAS) encountered in routine radiology practice. MATERIAL AND METHODS: Morphological appearances of (n = 11) LC-CAS detected during routine radiological reporting of chest CT scans were studied. Patient demographics, clinical history, characteristics of LC-CAS including location, size, wall thickening, diffuse nodularity, eccentric nodule, ground glass change, emphysema and pathology results were collected from the hospital's internal database. RESULTS: Patients with LC-CAS (9F/2M) were between 49 and 77 years (mean 63.18 years). All patients (n = 11) had a history of smoking. LC-CAS had a characteristic multicystic bubbly appearance. Average size of CAS at initial detection of LC was 2.52 cm (range 1.3-4 cm). Lesions were located in the RLL (n = 4), RML (n = 2), RUL (n = 1), LLL (n = 1) and LUL (n = 3) with no lobar predilection and were more commonly peripheral (n = 7) than central (n = 4). Ground glass change (n = 2), extrinsic nodules (n = 4), diffuse wall nodularity (n = 3) and intrinsic nodules (n = 2) were observed and prompted biopsy. Lesions ranged between T1a to T4. Most cancers were T1a N0 (n = 5). Adenocarcinomas formed the majority of cases (n = 9). CONCLUSION: LC-CAS present as new development of diffuse nodularity, eccentric nodules or ground glass change associated with CAS. These are more commonly adenocarcinomas on histology. Recognition of CAS and appropriate malignancy workup when suspicious features are observed is essential to enable early detection of lung cancer.

Comparison of sonography and magnetic resonance imaging for spring ligament abnormalities: preliminary study.

OBJECTIVE: The purpose of this study was to determine whether sonography is as accurate as magnetic resonance (MR) imaging for depicting abnormalities of the spring ligament in patients with symptomatic posterior tibial tendon (PTT) dysfunction. METHODS: Sixteen patients (18 ligaments) with symptomatic PTT dysfunction were prospectively evaluated with sonography and MR imaging. RESULTS: Magnetic resonance imaging showed spring ligament tears in 8 of 18 feet, including 6 incomplete tears and 2 complete tears. Sonography showed spring ligament tears in 7 of 18 feet, including 6 incomplete tears and 1 complete tear. The findings of sonography and MR imaging were concordant in 17 of 18 feet (94%). Six of the 8 spring ligament tears on MR imaging were associated with posterior tibial tendinosis or tears. CONCLUSIONS: Sonography is an effective imaging option in assessing spring ligament abnormalities in patients with symptomatic PTT dysfunction.