Automatic segmentation of articular cartilage from combined assessment of sodium and proton MR knee images

Abstract

Purpose: MRI is the first-line modality to diagnose meniscal pathology. Possible alternative to MRI is an ultrasound scanning which is quick to perform and less costly. The aim of this study was to assess the accuracy of high resolution ultrasonography in the diagnosis of meniscal tears with arthroscopic examination as standard reference. Methods: Fifty pair of menisci were evaluated in 50 patients (23 females, 27 males, mean age ¼ 32.5 years, range ¼ 13-80 years). Knee examinations were performed with high resolution ultrasonography machine (Hi Vision Preirus, Hitachi, Japan) with 8-14 MHz linear transducer. Inclusion criteria for the study were 1) knees that needed to be treated or examined arthroscopically due to intra articular pathology, and 2) unilateral involvement. Exclusion criteria were a history of rheumatoid arthritis or other inflammatory disease, periarticular fracture, Paget's disease, joint infection, neuropathic arthropathy, acromegaly, gout, and pseudogout. Examiner was not informed preoperative diagnosis and laterality. After ultrasonographic examination, all patients underwent arthroscopic procedures within 1-3 days. After the final diagnosis about meniscal status was derived from surgical reports, ultrasonographic diagnosis was compared in terms of presence of tear as well as type of tear when tears were present. Results: The overall sensitivity, specificity, positive predictive value, and negative predictive value of ultrasonographic examination in the assessment of meniscal tears amounted to 90%, 70%, 92% and 64%, respectively. The statistical parameters were not statistically different in medial and lateral menisci. Sensitivity, specificity, positive predictive value and negative predictive value of ultrasonographic examination in the assessment of medial meniscal tears vs. lateral meniscal tears were 96% vs. 65%, 74% vs. 88%, 81% vs. 81%, and 94% vs. 76%, respectively. As for diagnostic ability in diagnosing the type of meniscal tear, the sensitivity and positive predictive value of horizontal tear, vertical tear, radial tear, flap tear, bucket handle tear, complex tear, discoid were 71% vs. 36%, 47% vs. 58%, 0% vs. 0%, 40% vs. 67%, 55% vs. 86%, 88% vs. 54%, 100% vs. 100%. Age, sex, body mass index (BMI), weight, did not have a statistically significant impact on the usefulness of ultrasonography. Conclusions: High resolution ultrasonography had high accuracy in the detecting the presence of tears both in medial and lateral menisci. But type of meniscal tear was difficult to diagnose.