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OBJECTIVE: To determine the inter-reader reliability and diagnostic performance of classification and severity scales of Neuropathy Score Reporting And Data System (NS-RADS) among readers of differing experience levels after limited teaching of the scoring system. METHODS: This is a multi-institutional, cross-sectional, retrospective study of MRI cases of proven peripheral neuropathy (PN) conditions. Thirty-two radiology readers with varying experience levels were recruited from different institutions. Each reader attended and received a structured presentation that described the NS-RADS classification system containing examples and reviewed published articles on this subject. The readers were then asked to perform NS-RADS scoring with recording of category, subcategory, and most likely diagnosis. Inter-reader agreements were evaluated by Conger's kappa and diagnostic accuracy was calculated for each reader as percent correct diagnosis. A linear mixed model was used to estimate and compare accuracy between trainees and attendings. RESULTS: Across all readers, agreement was good for NS-RADS category and moderate for subcategory. Inter-reader agreement of trainees was comparable to attendings (0.65 vs 0.65). Reader accuracy for attendings was 75% (95% CI 73%, 77%), slightly higher than for trainees (71% (69%, 72%), p = 0.0006) for nerves and comparable for muscles (attendings, 87.5% (95% CI 86.1-88.8%) and trainees, 86.6% (95% CI 85.2-87.9%), p = 0.4). NS-RADS accuracy was also higher than average accuracy for the most plausible diagnosis for attending radiologists at 67% (95% CI 63%, 71%) and for trainees at 65% (95% CI 60%, 69%) (p = 0.036). CONCLUSION: Non-expert radiologists interpreted PN conditions with good accuracy and moderate-to-good inter-reader reliability using the NS-RADS scoring system. CLINICAL RELEVANCE STATEMENT: The Neuropathy Score Reporting And Data System (NS-RADS) is an accurate and reliable MRI-based image scoring system for practical use for the diagnosis and grading of severity of peripheral neuromuscular disorders by both experienced and general radiologists. KEY POINTS: ⢠The Neuropathy Score Reporting And Data System (NS-RADS) can be used effectively by non-expert radiologists to categorize peripheral neuropathy. ⢠Across 32 different experience-level readers, the agreement was good for NS-RADS category and moderate for NS-RADS subcategory. ⢠NS-RADS accuracy was higher than the average accuracy for the most plausible diagnosis for both attending radiologists and trainees (at 75%, 71% and 65%, 65%, respectively).
RESUMEN
BACKGROUND: The aim of our study is to determine the accuracy of magnetic resonance imaging (MRI) scan in relation to arthroscopic findings in patients presenting with chronic ankle pain and/or instability. METHODS: All patients who underwent arthroscopy of the ankle as well as MRI from December 2005 to July 2008 in our institution were reviewed by the Orthopaedic surgeons. Twenty-four patients were identified and the results of MRI scans were compared with arthroscopic findings. This study specifically looked at anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL) and osteochondral lesions (OCD). Arthroscopic findings were considered as a gold standard. There were 12 female and 12 male patients with an average age 39 years (11-65 years). Time interval between MRI scan and arthroscopy was 7.0 months (2-18 months). RESULTS: In our study MRI showed 100% specificity for the diagnosis of ATFL and CFL tears and osteochondral lesions. However sensitivity was low particularly for CFL tears. Accuracy of MRI in detecting ATFL tear was 91.7%, CFL tear was 87.5% and osteochondral lesion was 83.3%. CONCLUSIONS: We conclude that MRI scan has very high specificity and positive predictive value in diagnosing tears of ATFL, CFL and osteochondral lesions. However sensitivity was low with MRI. In a symptomatic patient negative results on MRI must be viewed with caution and an arthroscopy may still be required for a definitive diagnosis and treatment. However high resolution scans may differ in their ability to pick up these lesions and further research is required to assess their efficiency as evidence is not currently available.
