Original Research Article MRI in Evaluation of Knee Cystic Lesions

Background: Cystic knee lesions (synovial cysts, bursae, ganglia, and meniscal cysts) are frequently discovered and can be divided into real cysts and lesions that simulate cysts (hematomas, seromas, abscesses and vascular lesions).

Aim of the Work: The aim of this study was to assess the role of magnetic resonance imaging in evaluation of cysts and cyst like lesions in and around the knee.

Subjects and Methods: From January 2018 to August 2019, 30 patients were referred from outpatient clinics and orthopedic surgery department to MRI unit of radiodiagnosis and medical imaging department at Tanta University Hospitals, for MRI evaluation of suspected knee cystic lesions.

Results: MRI was able to detect all clinically suspected cystic lesions within the knee. It also helped to describe morphology and it’s relation to surrounding tissues. 16.7% and 3.3% of the studied cystic lesions had fine and thick septa respectively, and 67 % of the studied cystic lesions had communication with the joints. MRI could identify the associated pathology of most of the detected cystic lesions (80%). The most common pathology were meniscal degeneration (26.7%) followed by meniscal tear and osteoarthritis (23.3%) and (20%) respectively. Ligament tear / sprain formed 6.7% of the total cysts while bone contusion forms 3.3%.

Conclusion: The findings of this study confirm that In spite of its high cost, limited availability and the need for highly expert radiologists, MRI remains the method of choice for both diagnosis, characterization and uncovering the associated pathology and cause of cystic lesions around the knee. The high ability of MRI to image soft tissues plays a key role.