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Association Between Thenar Musculature and Carpal Tunnel Syndrome

Halpern, Robert A; Huang, Shengnan; Dunham, Kevin; Petchprapa, Catherine; Wollstein, Ronit
PMID: 38299240
ISSN: 2424-8363
CID: 5627242

Deep Learning Diagnosis and Classification of Rotator Cuff Tears on Shoulder MRI

Lin, Dana J; Schwier, Michael; Geiger, Bernhard; Raithel, Esther; von Busch, Heinrich; Fritz, Jan; Kline, Mitchell; Brooks, Michael; Dunham, Kevin; Shukla, Mehool; Alaia, Erin F; Samim, Mohammad; Joshi, Vivek; Walter, William R; Ellermann, Jutta M; Ilaslan, Hakan; Rubin, David; Winalski, Carl S; Recht, Michael P
BACKGROUND:Detection of rotator cuff tears, a common cause of shoulder disability, can be time-consuming and subject to reader variability. Deep learning (DL) has the potential to increase radiologist accuracy and consistency. PURPOSE:The aim of this study was to develop a prototype DL model for detection and classification of rotator cuff tears on shoulder magnetic resonance imaging into no tear, partial-thickness tear, or full-thickness tear. MATERIALS AND METHODS:This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study included a total of 11,925 noncontrast shoulder magnetic resonance imaging scans from 2 institutions, with 11,405 for development and 520 dedicated for final testing. A DL ensemble algorithm was developed that used 4 series as input from each examination: fluid-sensitive sequences in 3 planes and a sagittal oblique T1-weighted sequence. Radiology reports served as ground truth for training with categories of no tear, partial tear, or full-thickness tear. A multireader study was conducted for the test set ground truth, which was determined by the majority vote of 3 readers per case. The ensemble comprised 4 parallel 3D ResNet50 convolutional neural network architectures trained via transfer learning and then adapted to the targeted domain. The final tear-type prediction was determined as the class with the highest probability, after averaging the class probabilities of the 4 individual models. RESULTS:The AUC overall for supraspinatus, infraspinatus, and subscapularis tendon tears was 0.93, 0.89, and 0.90, respectively. The model performed best for full-thickness supraspinatus, infraspinatus, and subscapularis tears with AUCs of 0.98, 0.99, and 0.95, respectively. Multisequence input demonstrated higher AUCs than single-sequence input for infraspinatus and subscapularis tendon tears, whereas coronal oblique fluid-sensitive and multisequence input showed similar AUCs for supraspinatus tendon tears. Model accuracy for tear types and overall accuracy were similar to that of the clinical readers. CONCLUSIONS:Deep learning diagnosis of rotator cuff tears is feasible with excellent diagnostic performance, particularly for full-thickness tears, with model accuracy similar to subspecialty-trained musculoskeletal radiologists.
PMID: 36728041
ISSN: 1536-0210
CID: 5502202

The Use of Ultrasound to Differentiate Between Gout and Infection in the Wrist [Case Report]

Dunham, Kevin; Tsoeriero, Paul; Wollstein, Ronit
BACKGROUND:Gout is a common condition and its prevalence is increasing. In the wrist, acute gouty arthritis is difficult to distinguish from infection and may occur concomitantly. Though aspiration is helpful, it is not always technically feasible or definitive. Imaging may assist in the differential diagnosis. CASE PRESENTATION/METHODS:Two cases are described in which the use of ultrasound evaluation assisted in the diagnosis and ultimate treatment. CONCLUSION/CONCLUSIONS:Ultrasound can be a helpful adjunct in the diagnosis of arthritis of the wrist, helping to tailor treatment in complex cases.
PMID: 35232364
ISSN: 1875-6360
CID: 5174382

Palmar Musculature: Does It Affect the Development of Carpal Tunnel Syndrome? A Pilot Study

Simcox, Trevor; Seo, Lauren; Dunham, Kevin; Huang, Shengnan; Petchprapa, Catherine; Wollstein, Ronit
PMID: 34109061
ISSN: 2163-3916
CID: 5017942

Labral and cartilage abnormalities in young patients with hip pain: accuracy of 3-Tesla indirect MR arthrography

Petchprapa, Catherine N; Rybak, Leon D; Dunham, Kevin S; Lattanzi, Riccardo; Recht, Michael P
OBJECTIVE: Assess the diagnostic accuracy of 3-T indirect magnetic resonance arthrography (iMRA) for hip cartilage and labral pathology detection using arthroscopy as the reference standard and compare it to the published performance of direct magnetic resonance arthrography (dMRA). MATERIALS AND METHODS: Between 2009 and 2011, 290 patients suspected of having femoroacetabular impingement underwent iMRA. Our study group consisted of 41 of these patients (17 males, mean age 35 years; 24 females, mean age 33 years) who did not have a prior history of hip surgery and who subsequently underwent arthroscopy. Two experienced musculoskeletal radiologists separately evaluated the randomized and anonymized studies for the presence and quadrant location of labral and cartilage pathology. These recorded data were compared to arthroscopic reports. RESULTS: Forty-one patients had labral pathology, 34 patients had acetabular and 5 patients had femoral cartilage pathology at arthroscopy. Sensitivity, specificity, accuracy, negative- and positive-predictive values for labral lesion detection were respectively 98, 99, 99, 99 and 98 %; for acetabular cartilage lesion detection they were 69, 98, 89, 87 and 95 %; for femoral cartilage lesion detection they were 69, 95, 93 and 39 %. Sensitivities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum were 100.0, 95.0, NA and 85.7 %, for acetabular cartilage were NA, 58.8, NA and 39.5 % and for femoral cartilage were 50.0, 33.3, 75.0 and 75.0 %). NA indicates results not available because of the absence of findings in those quadrants. Specificities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum (95.0, 100.0, 95.1, 67.5 %), acetabular (100.0, 85.7, 92.6, 79.5 %) and femoral cartilage (100.0, 94.7, 96.2, 85.9 %). CONCLUSION: iMRA at 3 T is accurate in detecting labral pathology suggesting that it is a viable alternative to dMRA.
PMID: 25277527
ISSN: 0364-2348
CID: 1283142

Demystifying radial imaging of the hip

Petchprapa, Catherine N; Dunham, Kevin S; Lattanzi, Riccardo; Recht, Michael P
The hip joint poses unique challenges at magnetic resonance (MR) imaging because of its shape and anatomic position. When conventional imaging planes are used, partial-volume averaging effects may substantially hamper the depiction of cartilage and labral damage at MR imaging. Such effects are most prevalent when the imaging plane is not perpendicular to the curvature of the joint and result in images that poorly depict or fail to depict cartilage and labral conditions. Partial-volume averaging, along with the inherently thin and closely apposed articular cartilage, may be partly to blame for the seemingly disparate reported sensitivities of MR imaging for depicting cartilage damage in the literature, which vary widely depending on whether arthrography was used. Fortunately, the multiplanar capability of MR imaging is not limited to standard anatomic planes. Radial sections, which are obtained perpendicular to the surfaces of the hip joint, provide a true cross section of the cartilage and labrum that conventional planes do not. Radial imaging is a reproducible technique that enhances the morphologic assessment of the articular cartilage and labrum. The additional information it provides is important because early damage occurs in the anterosuperior region of the hip in patients with femoroacetabular impingement. (c)RSNA, 2013.
PMID: 23674783
ISSN: 0271-5333
CID: 346592

A new method to analyze dGEMRIC measurements in femoroacetabular impingement: preliminary validation against arthroscopic findings

Lattanzi, R; Petchprapa, C; Glaser, C; Dunham, K; Mikheev, A V; Krigel, A; Mamisch, T C; Kim, Y-J; Rusinek, H; Recht, M
OBJECTIVE: To validate a new method to analyze delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) measurements in the hip for early assessment of cartilage defects in femoroacetabular impingement (FAI). METHODS: We performed a retrospective review of 10 hips in 10 FAI patients, who underwent hip arthroscopy. T(1)-weighted images and dGEMRIC T(1) maps were acquired at 1.5 T on coronal planes, including the anterior-superior, superior, posterior-superior hip cartilage. For all slices, a region of interest (ROI) was defined over the central portion of the femoral cartilage, assumed to be healthy, and T(1) values (x) were transformed to standard scores (z) using z = (x -mu)/sigma, where mu and sigma are the average and standard deviation of T(1) in the femoral ROI. Diagnostic performance of the resulting standardized dGEMRIC maps was evaluated against intraoperative findings and compared with that of a previously proposed dGEMRIC analysis as well as morphologic assessment. RESULTS: Assuming z = -2 or z = -3 as the threshold between normal and degenerated cartilage, sensitivity, specificity and accuracy were 88%, 51% and 62%, and 71%, 63% and 65%, respectively. By using T(1) = 500 ms as single threshold for all dGEMRIC T(1) maps, these values became 47%, 58% and 55%, whereas they were 47%, 79% and 70% for morphologic evaluation. CONCLUSIONS: Standardized dGEMRIC can increase the sensitivity in detecting abnormal cartilage in FAI and has the potential to improve the clinical interpretation of dGEMRIC measurements in FAI, by removing the effect of inter- and intra-patient T(1) variability.
PMID: 22771774
ISSN: 1063-4584
CID: 177023

Anatomic variants and pitfalls of the labrum, glenoid cartilage, and glenohumeral ligaments

Dunham, Kevin S; Bencardino, Jenny T; Rokito, Andrew S
Magnetic resonance (MR) imaging is the primary diagnostic imaging modality for the evaluation of patients with suspected internal derangement of the shoulder joint. Awareness and understanding of the complex anatomy of the shoulder articulation and the ability to recognize normal anatomic variants and potential imaging pitfalls are critical to accurate interpretation of conventional and arthrographic MR imaging studies. This review discusses the normal anatomy and anatomic variants of the glenoid labrum, articular cartilage, and glenohumeral ligaments. An improved understanding of normal anatomy, biomechanics, and variants will help to avoid potential pitfalls in the interpretation of noncontrast and arthrographic shoulder MR imaging examinations.
PMID: 22469401
ISSN: 1064-9689
CID: 163584

Gene knockout of glycine transporter 1: characterization of the behavioral phenotype

Tsai, Guochuan; Ralph-Williams, Rebecca J; Martina, Marzia; Bergeron, Richard; Berger-Sweeney, Joanne; Dunham, Kevin S; Jiang, Zhichun; Caine, S Barak; Coyle, Joseph T
N-methyl-d-aspartate receptor (NMDAR) activation requires both the binding of glutamate to its recognition site and occupancy of the strychnine insensitive glycine modulatory site (GMS). Pharmacological studies suggest that the glycine transporter, GlyT1, maintains subsaturating concentrations of glycine at synaptic NMDARs. To characterize further the role of GlyT1, we generated mice in which the gene encoding GlyT1 was inactivated by homologous recombination through insertion of a PGK-Neo cassette in place of exons 2 and 3. Real-time quantitative PCR revealed no transcripts in newborn homozygous [GlyT1(-/-)] mice and a 50% reduction in heterozygous (HZ) [GlyT1(+/-)] mice as compared with WT littermates. The activity of Na(+)-dependent glycine transport in forebrain homogenates was similarly affected. Homozygous mice died within 12 h of birth. In acute hippocampal slices, exogenous glycine or d-serine (10 microM) enhanced NMDAR currents with Schaffer collateral stimulation in WT mice but not HZ mice, suggesting that the GMS was more occupied in the latter. The NMDAR/alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor ratio of the excitatory postsynaptic currents was significantly increased in the HZ mice. In the water maze, the HZ mice exhibited better spatial retention. Furthermore, HZ mice were less sensitive to an amphetamine disruption of prepulse inhibition than WT mice but were more sensitive to the effects of MK-801. Thus, reduced expression of GlyT1 enhances hippocampal NMDAR function and memory retention and protects against an amphetamine disruption of sensory gating, suggesting that drugs which inhibit GlyT1 might have both cognitive enhancing and antipsychotic effects
PMID: 15159536
ISSN: 0027-8424
CID: 134563

Early embryonic death of glutamate carboxypeptidase II (NAALADase) homozygous mutants

Tsai, G; Dunham, K S; Drager, U; Grier, A; Anderson, C; Collura, J; Coyle, J T
Glutamate carboxypeptidase II (EC catalyzes the hydrolysis (Km = 0.2 microM) of the neuropeptide N-acetylaspartylglutamate to yield N-acetylaspartate and glutamate and also serves as a high-affinity folate hydrolase in the gut, cleaving the polyglutamate chain to permit the absorption of folate. N-acetylaspartylglutamate is an agonist at the mGluR3 metabotropic receptor and a source of extracellular glutamate through hydrolysis by glutamate carboxypeptidase II. Given the important role of glutamate in brain development and function, we were interested in the effects of a null mutation of glutamate carboxypeptidase II that would potentiate the effects of N-acetylaspartylglutamate. The PGK-Neomycin cassette was inserted to delete exons 9 and 10, which we previously demonstrated encode for the zinc ligand domain essential for enzyme activity. Successful germline transmission was obtained from chimeras derived from embryonic stem cells with the targeted mutation of glutamate carboxypeptidase II. Homozygous null mutants did not survive beyond embryonic day 8. Folate supplementation of the heterozygous mothers did not rescue the homozygous embryos. Mice heterozygous for the null mutation appeared grossly normal and expressed both mutated and wild-type mRNA but the activity of glutamate carboxypeptidase II is comparable to the wild-type mice. The results indicate that the expression of glutamate carboxypeptidase II is upregulated when one allele is inactivated and that its activity is essential for early embryogenesis
PMID: 14556233
ISSN: 0887-4476
CID: 134556