MR imaging of the knee - an audit of practice

ABSTRACT

Magnetic resonance imaging [MRI] scan has shown constant accuracy in diagnosing various knee pathologies. A positive predictive value of upto 98% has been documented in various studies. It is completely non-invasive non radioactive and diagnostic accuracy is comparable to arthroscopy [64-94%]. We present an audit of 217 consecutive patients from the waiting list on knee arthroscopy who underwent MRI scan. The scans were reported by one consultant radiologist. The results of MRI were compared against preoperative diagnosis and the influence of this investigation on decision making was evaluated. Significant number of patients had a change in diagnosis [54.4%] and alteration in treatment plan [36.4%] because of inaccuracies in the clinical diagnosis. We believe that MRI scan can help the clinician in making an accurate preoperative diagnosis and target the arthroscopy to specific lesions. This is a non-invasive investigation which can replace diagnostic arthroscopy