Smartphone application with 3D-printed needle guide for faster and more accurate CT-guided interventions in a phantom.

OBJECTIVE: This study is to determine whether a needle guidance device combining a 3D-printed component with a smartphone would decrease the number of passes and time required to perform a standard CT-guided needle procedure in a phantom study. MATERIALS AND METHODS: A 3D-printed mechanical guide with built-in apertures for various needle sizes was designed and printed. It was mounted on a smartphone and used to direct commercially available spring-loaded biopsy devices. A smartphone software application was developed to use the phone's sensors to provide the real-time location of a lesion in space, based on parameters derived from preprocedural CT images. The physical linkage of the guide, smartphone, and needle allowed the operator to manipulate the assembly as a single unit, with real-time graphical representation of the lesion shown on the smartphone display. Two radiology trainees and 3 staff radiologists targeted 5 lesions with and without the device (50 total procedures). The number of passes and time taken to reach each lesion were determined. RESULTS: Use of the smartphone needle guide decreased the mean number of passes (with guide, 1.8; without guide, 3.4; P < 0.001) and mean time taken (with guide, 1.6 min; without guide, 2.7 min; P = 0.005) to perform a standard CT-guided procedure. On average, the decreases in number of passes and procedure time were more pronounced among trainees (P < 0.001). CONCLUSION: The combination of a mechanical guide and smartphone can reduce the number of needle passes and the amount of time needed to reach a lesion in a phantom for both trainees and experienced radiologists.

3D MRI of the Knee.

Three-dimensional (3D) magnetic resonance imaging (MRI) of the knee is widely used in musculoskeletal (MSK) imaging. Currently, 3D sequences are most commonly used for morphological imaging. Isotropic 3D MRI provides higher out-of-plane resolution than standard two-dimensional (2D) MRI, leading to reduced partial volume averaging artifacts and allowing for multiplanar reconstructions in any plane with any thickness from a single high-resolution isotropic acquisition. Specifically, isotropic 3D fast spin-echo imaging, with options for tissue weighting similar to those used in multiplanar 2D FSE imaging, is of particular interest to MSK radiologists. New applications for 3D spatially encoded sequences are also increasingly available for clinical use. These applications offer advantages over standard 2D techniques for metal artifact reduction, quantitative cartilage imaging, nerve imaging, and bone shape analysis. Emerging fast imaging techniques can be used to overcome the long acquisition times that have limited the adoption of 3D imaging in clinical protocols.

Percutaneous ultrasonic tenotomy with the TX-1 device versus surgical tenotomy for the treatment of common extensor tendinosis.

OBJECTIVE: To compare outcomes in patients treated for chronic common extensor tendinosis with percutaneous ultrasonic tenotomy (TX-1 device) versus surgical tenotomy. MATERIALS AND METHODS: Outcomes from consecutive patients who underwent percutaneous tenotomy with the TX-1 device were compared with outcomes from consecutive patients who underwent surgical tenotomy. Patients were contacted to retrospectively assess their outcomes at 4 time points: before treatment, 2 weeks after treatment, 3 to 6 months after treatment, and 12 months after treatment. Outcomes were assessed using the quick disabilities of the arm, shoulder, and hand score (QuickDASH) and the Oxford elbow score (OES). Student's t tests were used to compare postprocedural versus preprocedural scores and percutaneous versus surgical tenotomy scores. RESULTS: Response rates were 23 of 43 and 10 of 47 for surveyed percutaneous and surgical tenotomy patients, respectively. There were significant improvements from preprocedural scores in all primary outcome measures at 3-to-6-month and 12-month time points for both procedures. No significant changes from preprocedural scores were seen for either procedure at 2 weeks after treatment or between percutaneous and surgical tenotomy in preprocedural or postprocedural scores for any outcome measure. At 2 weeks, improved percutaneous tenotomy scores approached significance compared with percutaneous preprocedural QuickDASH (p = 0.060) and surgical 2-week OES function domain (p = 0.074) scores. CONCLUSION: Ultrasonic percutaneous tenotomy with the TX-1 device and surgical tenotomy have similar outcomes for chronic common extensor tendinosis, with significant symptomatic improvement occurring after 3 to 6 months. Larger studies are needed to assess for differences at 2 weeks.

Comparing an accelerated 3D fast spin-echo sequence (CS-SPACE) for knee 3-T magnetic resonance imaging with traditional 3D fast spin-echo (SPACE) and routine 2D sequences.

PURPOSE: To compare a faster, new, high-resolution accelerated 3D-fast-spin-echo (3D-FSE) acquisition sequence (CS-SPACE) to traditional 2D and high-resolution 3D sequences for knee 3-T magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twenty patients received knee MRIs that included routine 2D (T1, PD ± FS, T2-FS; 0.5 × 0.5 × 3 mm3; ∼10 min), traditional 3D FSE (SPACE-PD-FS; 0.5 × 0.5 × 0.5 mm3; ∼7.5 min), and accelerated 3D-FSE prototype (CS-SPACE-PD-FS; 0.5 × 0.5 × 0.5 mm3; ∼5 min) acquisitions on a 3-T MRI system (Siemens MAGNETOM Skyra). Three musculoskeletal radiologists (MSKRs) prospectively and independently reviewed the studies with graded surveys comparing image and diagnostic quality. Tissue-specific signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were also compared. RESULTS: MSKR-perceived diagnostic quality of cartilage was significantly higher for CS-SPACE than for SPACE and 2D sequences (p < 0.001). Assessment of diagnostic quality of menisci and synovial fluid was higher for CS-SPACE than for SPACE (p < 0.001). CS-SPACE was not significantly different from SPACE but had lower assessments than 2D sequences for evaluation of bones, ligaments, muscles, and fat (p ≤ 0.004). 3D sequences had higher spatial resolution, but lower overall assessed contrast (p < 0.001). Overall image quality from CS-SPACE was assessed as higher than SPACE (p = 0.007), but lower than 2D sequences (p < 0.001). Compared to SPACE, CS-SPACE had higher fluid SNR and CNR against all other tissues (all p < 0.001). CONCLUSIONS: The CS-SPACE prototype allows for faster isotropic acquisitions of knee MRIs over currently used protocols. High fluid-to-cartilage CNR and higher spatial resolution over routine 2D sequences may present a valuable role for CS-SPACE in the evaluation of cartilage and menisci.

Development and Operationalization of an Automated Workflow for Correlation of Knee MRI and Arthroscopy Findings.

OBJECTIVE: In this study, we sought to establish and evaluate an automated workflow to prospectively capture and correlate knee MRI findings with surgical findings in a large medical center. METHODS: This retrospective analysis included data from patients who had undergone knee MRI followed by arthroscopic knee surgery within 6 months during a 2-year period (2019-2020). Discrete data were automatically extracted from a structured knee MRI report template implementing pick lists. Operative findings were recorded discretely by surgeons using a custom-built web-based telephone application. MRI findings were classified as true-positive, true-negative, false-positive, or false-negative for medial meniscus (MM), lateral meniscus (LM), and anterior cruciate ligament (ACL) tears, with arthroscopy used as the reference standard. An automated dashboard displaying up-to-date concordance and individual and group accuracy was enabled for each radiologist. Manual correlation between MRI and operative reports was performed on a random sample of 10% of cases for comparison with automatically derived values. RESULTS: Data from 3,187 patients (1,669 male; mean age, 47 years) were analyzed. Automatic correlation was available for 60% of cases, with an overall MRI diagnostic accuracy of 93% (MM, 92%; LM, 89%; ACL, 98%). In cases reviewed manually, the number of cases that could be correlated with surgery was higher (84%). Concordance between automated and manual review was 99% when both were available (MM, 98%; LM, 100%; ACL, 99%). CONCLUSION: This automated system was able to accurately and continuously assess correlation between imaging and operative findings for a large number of MRI examinations.

Quantitative MRI for Evaluation of Musculoskeletal Disease: Cartilage and Muscle Composition, Joint Inflammation, and Biomechanics in Osteoarthritis.

ABSTRACT: Magnetic resonance imaging (MRI) is a valuable tool for evaluating musculoskeletal disease as it offers a range of image contrasts that are sensitive to underlying tissue biochemical composition and microstructure. Although MRI has the ability to provide high-resolution, information-rich images suitable for musculoskeletal applications, most MRI utilization remains in qualitative evaluation. Quantitative MRI (qMRI) provides additional value beyond qualitative assessment via objective metrics that can support disease characterization, disease progression monitoring, or therapy response. In this review, musculoskeletal qMRI techniques are summarized with a focus on techniques developed for osteoarthritis evaluation. Cartilage compositional MRI methods are described with a detailed discussion on relaxometric mapping (T 2 , T 2 *, T 1ρ ) without contrast agents. Methods to assess inflammation are described, including perfusion imaging, volume and signal changes, contrast-enhanced T 1 mapping, and semiquantitative scoring systems. Quantitative characterization of structure and function by bone shape modeling and joint kinematics are described. Muscle evaluation by qMRI is discussed, including size (area, volume), relaxometric mapping (T 1 , T 2 , T 1ρ ), fat fraction quantification, diffusion imaging, and metabolic assessment by 31 P-MR and creatine chemical exchange saturation transfer. Other notable technologies to support qMRI in musculoskeletal evaluation are described, including magnetic resonance fingerprinting, ultrashort echo time imaging, ultrahigh-field MRI, and hybrid MRI-positron emission tomography. Challenges for adopting and using qMRI in musculoskeletal evaluation are discussed, including the need for metal artifact suppression and qMRI standardization.

Student perspectives on assessment: experience in a competency-based portfolio system.

Despite considerable evidence recognizing the importance of learners' perceptions of the assessment process, there is little literature depicting the participants' experience. We aim to capture these perceptions in order to gain insights into the strengths and weaknesses of a competency-based assessment system. Cleveland Clinic Lerner College of Medicine has implemented a learner-centered portfolio assessment system built around competency standards and continuous formative feedback. Promotion of students is based upon their feedback-supported portfolio essays, but feedback itself is individualized and formative in nature under the umbrella of the competencies. Importantly, there are no grades or ranking awarded for the competencies or at promotion. Four students share personal reflections of their experience to illuminate themes from the subjective experience of the learner and to understand how to align the learners' interests with the requirements of an assessment program.

Accuracy of 3-Tesla magnetic resonance imaging for the diagnosis of intra-articular knee injuries in children and teenagers.

BACKGROUND: Magnetic resonance imaging (MRI) is a commonly used tool for the diagnosis of intra-articular knee pathologies. Although many studies have reported the accuracy of MRI in the adult population, fewer studies have investigated these tests in younger patients. Furthermore, these studies have shown a higher variability in both the sensitivity and the specificity of MRI for these knee injuries in this age group. Advancements in MRI technology, such as the 3-Tesla (3T) MRI magnet, have shown promising results for musculoskeletal injury diagnosis in adults. This study aims to evaluate 3 T MRI for the diagnosis of intra-articular knee pathologies in a pediatric and adolescent patient population. METHODS: The records of 116 patients (119 knees) under the age of 20 years who underwent 3 T MRI studies of the knee and subsequent knee arthroscopy were reviewed retrospectively. The MRI report from the musculoskeletal radiology staff, the interpretation from the staff orthopedic surgeon, and the operative note dictations were compared, with a focus on meniscus and anterior cruciate ligament (ACL) pathologies. Seventeen orthopedic staff reads were not obtainable. Arthroscopy was used as the gold standard for diagnosis. RESULTS: The average age at MRI exam was 16.0 years and at surgery was 16.2 years. Using the musculoskeletal radiologist interpretation, the sensitivity and the specificity of 3 T MRI were 81.0% and 90.9% for medial meniscus injuries, 68.8% and 93% for lateral meniscus injuries, and 97.9% and 98.6% for ACL injuries, respectively. The orthopedic surgeon's interpretation of 3 T MRI had a sensitivity and specificity of 75.7% and 92.4% for medial meniscus injuries, 69.8% and 98.3% for lateral meniscus injuries, and 100% and 98.6% for ACL injuries, respectively. Posterior horn tears had the greatest discrepancies. CONCLUSIONS: When performed on pediatric and adolescent patients, newer 3 T MRI studies have excellent accuracy for diagnosing ACL tears. These studies also show a higher accuracy for the diagnosis of medial meniscal tears than lateral meniscal tears. LEVEL OF EVIDENCE: Diagnostic study--Level 2.

Meniscal Treatment as a Predictor of Worse Articular Cartilage Damage on MRI at 2 Years After ACL Reconstruction: The MOON Nested Cohort.

BACKGROUND: Patients undergoing anterior cruciate ligament reconstruction (ACLR) are at an increased risk for posttraumatic osteoarthritis (PTOA). While we have previously shown that meniscal treatment with ACLR predicts more radiographic PTOA at 2 to 3 years postoperatively, there are a limited number of similar studies that have assessed cartilage directly with magnetic resonance imaging (MRI). HYPOTHESIS: Meniscal repair or partial meniscectomy at the time of ACLR independently predicts more articular cartilage damage on 2- to 3-year postoperative MRI compared with a healthy meniscus or a stable untreated tear. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A consecutive series of patients undergoing ACLR from 1 site within the prospective, nested Multicenter Orthopaedic Outcomes Network (MOON) cohort underwent bilateral knee MRI at 2 to 3 years postoperatively. Patients were aged <36 years without previous knee injuries, were injured while playing sports, and had no history of concomitant ligament surgery or contralateral knee surgery. MRI scans were graded by a board-certified musculoskeletal radiologist using the modified MRI Osteoarthritis Knee Score (MOAKS). A proportional odds logistic regression model was built to predict a MOAKS-based cartilage damage score (CDS) relative to the contralateral control knee for each compartment as well as for the whole knee, pooled by meniscal treatment, while controlling for sex, age, body mass index, baseline Marx activity score, and baseline operative cartilage grade. For analysis, meniscal injuries surgically treated with partial meniscectomy or meniscal repair were grouped together. RESULTS: The cohort included 60 patients (32 female; median age, 18.7 years). Concomitant meniscal treatment at the time of index ACLR was performed in 17 medial menisci (13 meniscal repair and 4 partial meniscectomy) and 27 lateral menisci (3 meniscal repair and 24 partial meniscectomy). Articular cartilage damage was worse in the ipsilateral reconstructed knee (P < .001). A meniscal injury requiring surgical treatment with ACLR predicted a worse CDS for medial meniscal treatment (medial compartment CDS: P = .005; whole joint CDS: P < .001) and lateral meniscal treatment (lateral compartment CDS: P = .038; whole joint CDS: P = .863). Other predictors of a worse relative CDS included age for the medial compartment (P < .001), surgically observed articular cartilage damage for the patellofemoral compartment (P = .048), and body mass index (P = .007) and age (P = .020) for the whole joint. CONCLUSION: A meniscal injury requiring surgical treatment with partial meniscectomy or meniscal repair at the time of ACLR predicted worse articular cartilage damage on MRI at 2 to 3 years after surgery. Further research is required to differentiate between the effects of partial meniscectomy and meniscal repair.

Do Bone-Patellar Tendon-Bone ACL-Reconstructed Knees Have More Signs of Patellofemoral Posttraumatic Osteoarthritis Than Their Uninjured Contralateral Knees at 2 Years?

BACKGROUND: The prevalence of patellofemoral joint (PFJ) osteoarthritis ranges from 8% to 47% at 7 to 10 years after anterior cruciate ligament reconstruction (ACLR) using bone-patellar tendon-bone (BTB) autograft. In performing BTB ACLR, some hypothesize that either trauma caused by harvest of the BTB autograft or altered biomechanics contributes to PFJ posttraumatic osteoarthritis. PURPOSE/HYPOTHESIS: To determine whether knees with ACLR using a BTB autograft show early signs of posttraumatic osteoarthritis as compared with the contralateral uninjured knee 2 years after ACLR. We hypothesized that a BTB autograft will not increase the prevalence of PFJ osteoarthritis. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Bilateral knee 3-T magnetic resonance imaging (MRI) scans were collected in 57 patients (mean age, 20.3 years; 28 men) from a single site at a minimum of 2 years after ACLR. Structural MRI assessment of the knees was performed using the MRI Osteoarthritis Knee Score semiquantitative scoring system by a board-certified musculoskeletal radiologist. The presence of cartilage defects in the patellofemoral compartment was compared between the reconstructed and contralateral uninjured knees using logistic regression analyses. RESULTS: There were no significant differences in the prevalence of cartilage defects (full thickness or any thickness) in the PFJ between the BTB ACLR knees and the contralateral control knees: 38.6% of BTB ACLR knees had PFJ cartilage defects versus 31.6% of contralateral control knees (P > .391). The 95% CI for the difference between these groups was -9.0% to 23.0%. CONCLUSION: When comparing BTB ACLR knees with the uninjured contralateral knees in the study patients, we failed to observe statistically significant differences in the prevalence of PFJ cartilage lesions of full thickness or any thickness. These results should be used in shared decision-making with athletes when choosing the appropriate autograft during reconstruction. Our wide 95% CIs secondary to a smaller sample size demonstrate a need for larger studies in this area to more accurately describe the difference between the operative and contralateral knees.

Thrower's Shoulder: An Approach to MR Imaging Interpretation.

In this article, the authors aim to focus on the challenges of interpreting shoulder MR imaging in the throwing athlete with an approach formed by evidence-based literature and clinical experience, with a particular focus on superior labrum tears.