Leon Rybak

Purpose The aim of this study is to evaluate the treatment response of patients with osteoid osteoma (OO) following radiofrequency ablation (RFA) and identify factors influencing the time to complete pain relief post-treatment. Materials and methods This is a retrospective cohort study of patients who underwent RFA for OO between 2010 and 2023. Demographic, clinical data, and time between symptoms onset to diagnosis and RFA were recorded. CTs were reviewed for OO location (upper extremity, lower extremity, spine/pelvis), intra-articular versus extra-articular lesions, nidus size, degree of peripheral bone formation, and presence of vessel sign. Procedural related information included needle approach, RFA active tip length, and number of RFA cycles. Statistical analysis was made on factors and their correlation to complete pain relief. Results Out of 63 patients included in our study (mean age 19.3 ± 10.6), OO were located in the upper extremity (n = 7, 11%), lower extremity (n = 48, 76%), and pelvis/spine (n = 8, 13%). OO in the pelvis/spine achieved the quickest complete pain relief (14 days) compared to those in lower (25 days, 11 days longer) and upper extremity (54 days, 40 days longer) respectively (p = 0.04). Vessel sign had significant association with shorter time to complete pain relief (p = 0.03). Longer duration of symptoms until diagnosis or RFA, larger nidus, more bone formation, and extra-articular OO responded slower to RFA, though statistical significance was not reached. Conclusions Anatomical location and certain imaging characteristics of OO may have association with time to complete pain relief following RFA. The findings can potentially help optimizing patient counseling with more realistic expectations and symptom management strategies prior to and following RFA.

OBJECTIVE. Deep learning (DL) image reconstruction has the potential to disrupt the current state of MRI by significantly decreasing the time required for MRI examinations. Our goal was to use DL t...

Objective: Predictive biomarkers of progression in knee osteoarthritis are sought to enable clinical trials of structure-modifying drugs. A peripheral blood leukocyte (PBL) inflammatory gene signature, MRI-based bone marrow lesions (BML) and meniscus extrusion scores, meniscal lesions, and osteophytes on X-ray each have been shown separately to predict radiographic joint space narrowing (JSN) in subjects with symptomatic knee osteoarthritis (SKOA). In these studies, we determined whether the combination of the PBL inflammatory gene expression and these imaging findings at baseline enhanced the prognostic value of either alone.Methods: PBL inflammatory gene expression (increased mRNA for IL-1β, TNFα, and COX-2), routine radiographs, and 3T knee MRI were assessed in two independent populations with SKOA: an NYU cohort and the Osteoarthritis Initiative (OAI). At baseline and 24 months, subjects underwent standardized fixed-flexion knee radiographs and knee MRI. Medial JSN (mJSN) was determined as the change in medial JSW. Progressors were defined by an mJSN cut-point (≥ 0.5 mm/24 months). Models were evaluated by odds ratios (OR) and area under the receiver operating characteristic curve (AUC).Results: We validated our prior finding in these two independent (NYU and OAI) cohorts, individually and combined, that an inflammatory PBL inflammatory gene expression predicted radiographic progression of SKOA after adjustment for age, sex, and BMI. Similarly, the presence of baseline BML and meniscal lesions by MRI or semiquantitative osteophyte score on X-ray each predicted radiographic medial JSN at 24 months. The combination of the PBL inflammatory gene expression and medial BML increased the AUC from 0.66 (p = 0.004) to 0.75 (p < 0.0001) and the odds ratio from 6.31 to 19.10 (p < 0.0001) in the combined cohort of 473 subjects. The addition of osteophyte score to BML and PBL inflammatory gene expression further increased the predictive value of any single biomarker. A causal analysis demonstrated that the PBL inflammatory gene expression and BML independently influenced mJSN.Conclusion: The use of the PBL inflammatory gene expression together with imaging biomarkers as combinatorial predictive biomarkers, markedly enhances the identification of radiographic progressors. The identification of the SKOA population at risk for progression will help in the future design of disease-modifying OA drug trials and personalized medicine strategies.

Background: To investigate the expression of vascular adhesion protein-1 (VAP-1) in joint tissues and serum in symptomatic knee osteoarthritis (SKOA) patients and examine whether VAP-1 levels predict increased risk of disease severity in a cross-sectional study. Methods: Baseline VAP-1 expression and soluble VAP-1 (sVAP-1) levels were assessed in the synovium synovial fluid and in the serum in cohorts of patients with tibiofemoral medial knee OA and healthy subjects. Standardized fixed-flexion poster anterior knee radiographs scored for Kellgren–Lawrence (KL) grade (0–4) and medial joint space width (JSW). KL1/2 vs. KL3/4 scores defined early and advanced radiographic severity, respectively. Biochemical markers assessed in serum or synovial fluids (SF) comprised sVAP-1, interleukin 1 receptor antagonist (IL-1Ra), interleukin 6 (IL-6), soluble receptor for advanced glycation end-products (sRAGE), C-C motif chemokine ligand 2 (CCL2), C-C motif chemokine ligand 4 (CCL4), cluster of differentiation 163 (CD163), high sensitivity C-reactive protein (hsCRP), and matrix metalloproteinases (MMPs)-1,-3,-9. Associations between biomarkers and radiographic severity KL1/2 vs. KL3/4 (logistic regression controlling for covariates) and pain (Spearman correlation) were evaluated. Results: Elevated levels of sVAP-1 observed in OA synovial fluid and VAP-1 expression in synovium based on immunohistochemical, microarray, and real-time quantitative polymerase chain reaction (qRT-PCR) analyses. However, serum sVAP-1 levels in OA patients were lower than in controls and inversely correlated with pain and inflammation markers (hsCRP and soluble RAGE). Soluble VAP-1 levels in serum were also lower in radiographically advanced (KL3/4) compared with early KL1/2 knee SKOA patients. Conclusion: Local (synovial fluid) semicarbazide-sensitive amine oxidase (SSAO)/sVAP-1 levels were elevated in OA and correlated with radiographic severity. However, systemic (serum) sVAP-1 levels were lower in SKOA patients than normal and inversely correlated with pain and inflammation markers. Serum sVAP-1 levels were higher in early (KL1/2) compared with advanced (KL3/4) SKOA patients.

Purpose: To develop an accelerated SEMAC metal implant MRI technique (Sparse‐SEMAC) with reduced scan time and improved metal distortion correction.Methods: Sparse‐SEMAC jointly exploits the inherent sparsity along the additional phase‐encoding dimension and multicoil encoding capabilities to significantly accelerate data acquisition. A prototype pulse sequence with pseudorandom k_y‐k_z undersampling and an inline image reconstruction was developed for integration in clinical studies. Three patients with hip implants were imaged using the proposed Sparse‐SEMAC with eight‐fold acceleration and compared with the standard‐SEMAC technique used in clinical studies (three‐fold GRAPPA acceleration). Measurements were performed with SEMAC‐encoding steps (SES) = 15 for Sparse‐SEMAC and SES = 9 for Standard‐SEMAC using high spatial resolution Proton Density (PD) and lower‐resolution STIR acquisitions. Two expert musculoskeletal (MSK) radiologists performed a consensus reading to score image‐quality parameters.Results: Sparse‐SEMAC enables up to eight‐fold acceleration of data acquisition that results in two‐fold scan time reductions, compared with Standard‐SEMAC, with improved metal artifact correction for patients with hip implants without degrading spatial resolution.Conclusion: The high acceleration enabled by Sparse‐SEMAC would enable clinically feasible examination times with improved correction of metal distortion. Magn Reson Med 78:79–87, 2017. © 2016 International Society for Magnetic Resonance in Medicine

Three cases of PIN palsy following biceps repair are presented with clinical and imaging correlation. The imaging findings in these cases will be discussed and the orthopedic literature, as regards possible surgical approaches and technical factors believed to predispose to or prevent this complication, will be reviewed. It is important for radiologists to serve as consultants in these uncommon but sometimes devastating complications, helping to quickly and accurately recognize the imaging findings corresponding to the clinical symptoms and aiding the surgeon in diagnosis and treatment by identifying the possible causes and sites of nerve compression. Three cases of PIN palsy following biceps repair are presented with clinical and imaging correlation. The imaging findings in these cases will be discussed and the orthopedic literature, as regards possible surgical approaches and technical factors believed to predispose to or prevent this complication, will be reviewed. It is important for radiologists to serve as consultants in these uncommon but sometimes devastating complications, helping to quickly and accurately recognize the imaging findings corresponding to the clinical symptoms and aiding the surgeon in diagnosis and treatment by identifying the possible causes and sites of nerve compression.

Objective: Inflammatory mediators, such as prostaglandin E₂ (PGE₂) and interleukin‐1β (IL‐1β), are produced by osteoarthritic (OA) joint tissue, where they may contribute to disease pathogenesis. We undertook the present study to examine whether inflammation, evidenced in plasma and peripheral blood leukocytes (PBLs), reflects the presence, progression, or specific symptoms of symptomatic knee OA.Methods: Patients with symptomatic knee OA were enrolled in a 24‐month prospective study of radiographic progression. Standardized knee radiographs were obtained at baseline and 24 months. At baseline, levels of the plasma lipids PGE₂ and 15‐hydroxyeicosatetraenoic acid (15‐HETE) were measured, and transcriptome analysis of PBLs was performed by microarray and quantitative polymerase chain reaction.Results: Baseline PGE₂ synthase (PGES) levels determined by PBL microarray gene expression and plasma PGE₂ levels distinguished patients with symptomatic knee OA from non‐OA controls (area under the receiver operating characteristic curve [AUC] 0.87 and 0.89, respectively, P < 0.0001). Baseline plasma 15‐HETE levels were significantly elevated in patients with symptomatic knee OA versus non‐OA controls (P < 0.0195). In the 146 patients who completed the 24‐month study, elevated baseline expression of IL‐1β, tumor necrosis factor α, and cyclooxygenase 2 (COX‐2) messenger RNA in PBLs predicted higher risk of radiographic progression as evidenced by joint space narrowing (JSN). In a multivariate model, AUC point estimates of models containing COX‐2 in combination with demographic traits overlapped the confidence interval of the base model in 2 of the 3 JSN outcome measures (JSN >0.0 mm, JSN >0.2 mm, and JSN >0.5 mm; AUC 0.62–0.67).Conclusion: The inflammatory plasma lipid biomarkers PGE₂ and 15‐HETE identify patients with symptomatic knee OA, and the PBL inflammatory transcriptome identifies a subset of patients with symptomatic knee OA who are at increased risk of radiographic progression. These findings may reflect low‐grade inflammation in OA and may be useful as diagnostic and prognostic biomarkers in clinical development of disease‐modifying OA drugs.