Stetson Powell Orthopaedics and Sports Medicine, Burbank, California, USA.
Orthop J Sports Med. 2014 Jul 2;2(7):2325967114540407. doi: 10.1177/2325967114540407. eCollection 2014 Jul.
Many studies have compared the diagnostic capabilities of low-field magnetic resonance imaging (MRI) scanners to high-field MRI scanners; however, few have evaluated the low-field MRI diagnoses compared with intraoperative findings.
To determine the accuracy and sensitivity of low-field MRI scanners in diagnosing lesions of the rotator cuff and glenoid labrum.
Cohort study (diagnosis); Level of evidence, 3.
Over a 2-year period, MRI examinations without intra-articular contrast were performed on 79 patients for shoulder pathologies using an in-office 0.2-T extremity scanner. The MRI examinations were read by board-certified, musculoskeletal fellowship-trained radiologists. All patients underwent shoulder arthroscopy performed by a single sports fellowship-trained orthopaedic surgeon within a mean time of 56 days (range, 8-188 days) after the MRI examination. The mean patient age was 54 years (range, 18-81 years). Operative notes from the shoulder arthroscopies were then retrospectively reviewed by a single blinded observer, and the intraoperative findings were compared with the MRI reports.
For partial-thickness rotator cuff tears, the sensitivity, specificity, positive predictive value, and negative predictive value were 85%, 89%, 79%, and 92%, respectively. For full-thickness rotator cuff tears, the respective values were 97%, 100%, 100%, and 98%. For anterior labral lesions, the values were 86%, 99%, 86%, and 99%, and for superior labral anterior-posterior (SLAP) lesions, the values were 20%, 100%, 100%, and 79%, respectively.
Low-field MRI is an accurate tool for evaluation of partial- and full-thickness rotator cuff tears; however, it is not effective in diagnosing SLAP lesions. More information is needed to properly assess its ability to diagnose anterior and posterior labral lesions.
许多研究比较了低磁场磁共振成像（MRI）扫描仪与高磁场 MRI 扫描仪的诊断能力；然而，很少有研究评估低磁场 MRI 诊断与术中发现的比较。
确定低磁场 MRI 扫描仪在诊断肩袖和盂唇病变中的准确性和敏感性。
队列研究（诊断）；证据水平，3 级。
在 2 年期间，使用办公室内的 0.2-T 肢体扫描仪对 79 例肩部病变患者进行了无关节内对比的 MRI 检查。MRI 检查由经过董事会认证、具有肌肉骨骼专业 fellowship培训的放射科医生进行阅读。所有患者均在 MRI 检查后平均 56 天（范围为 8-188 天）内由一位具有运动专业 fellowship培训的骨科医生进行了肩关节镜检查。患者平均年龄为 54 岁（范围为 18-81 岁）。然后，由一位单独的盲法观察者回顾性审查肩关节镜手术记录，并将术中发现与 MRI 报告进行比较。
对于部分厚度肩袖撕裂，敏感性、特异性、阳性预测值和阴性预测值分别为 85%、89%、79%和 92%。对于全层肩袖撕裂，相应的值分别为 97%、100%、100%和 98%。对于前盂唇病变，其值分别为 86%、99%、86%和 99%，而对于上盂唇前-后（SLAP）病变，其值分别为 20%、100%、100%和 79%。
低磁场 MRI 是评估部分和全层肩袖撕裂的准确工具；然而，它在诊断 SLAP 病变方面效果不佳。需要更多信息来正确评估其诊断前、后盂唇病变的能力。
