Figuring out the "fronds"-synovial proliferative disorders of the knee. Poster No.: C-1209 Congress: ECR 2014 Type: Educational Exhibit Authors: S. Sivasubramanian; Tamil Nadu/IN Keywords: Imaging sequences, MR, Musculoskeletal joint, Developmental disease DOI: 10.1594/ecr2014/C-1209 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 21
Learning objectives To identify benign synovial pathologies and proliferative processes which occur more frequently than true neoplastic proliferations. Differentiate these benign synovial proliferative conditions based on specific imaging features and clinical background. Page 2 of 21
Background Tumor like proliferative lesions of the synovium are more common than true synovial tumors like synovial hemangioma,chondrosarcoma and metastasis. Synovial proliferative disorders of the knee form a distinct group of conditions which present with fronds and villi in the synovium of the joint. The exhibit aims at delineating the salient features of these conditions based on specific MRI findings.the disorders included are : Pigmented villo nodular synovitis. Lipoma arborescens Synovial chondromatosis Rheumatoid arthritis. The other conditions include hemophilic arthritis, hemorrhagic synovitis and chronic siderotic synovitis which can be identified based on typical clinical history. Page 3 of 21
Findings and procedure details Pigmented Villo Nodular synovitis: It is a mono articular synovial proliferative disorder characterised by hemosiderin laden macrophages within the hypertrophied synovial masses. No calcification is noted within the synovial proliferation. The pathology may be diffuse or focal,most commonly. adjacent the patello femoral joint. MRI findings : T1 - intermediate to hypo intense synovial proliferation - hypo intense erosions with thin margins - surrounding edema / associated appears hypo intense T2 - hypo intense to intermediate intensity of the synovium due to paramagnetic effect of iron. - edema/effusion appears hyperintense T2*GRE- low intensity deposits of hemosiderin noted within the synovial masses Lipoma arborescens It is fatty synovial or sub synovial infiltration.the synovial masses may range from small fronds to large ones filling almost the entire joint. The most preferred location is the supra patellar bursa. MRI findings: T1 - hyperintense synovial proliferation. T2 - hyperintense, synovium follows the signal intensity of fat. Page 4 of 21
- may have associated synovial effusion. PD FS. FSE - hyperintensity of the synovial proliferation suppressed. Synovial osteochondromatosis : It is a monoarticular synovial metaplastic disorder of unknown aetiology.though commonly intra articular,it can occur in the tendon sheaths and bursae.the disorder can occur secondary to joint surface disintegration in osteoarthritis. Synovial metaplasia results in villonodular projections that grow to form nodules,which later ossify.when these ossified nodules detach,they are nourished by the synovial fluid and become cartilaginous.multiple,round,similar sized calcified loose bodies may be seen on radiographs. MRI findings : T1 - lobulated intra articular masses isointense to muscle with multiple foci of low signal intensity. T2 -the masses are hyperintense to muscle with areas of hypointensity. Rheumatoid arthritis : It is a systemic disorder producing inflammatory arthritis with synovial proliferation and thickening.it can involve the knee resulting in a thickened edematous synovium with associated effusion, cartilage degradation, peri articular erosions and cysts. The exuberant,inflammatory synovial tissue that erodes the cartilage and bone is called pannus. MRI findings: T1 - erosions appear hypointense on T1 and hyperintense on T2. Lateral compartment involvement is more frequent. Marked enhancement seen on contrast. Page 5 of 21
T2 - effusion appears hyperintense. - diffuse hyaline cartilage loss. PD -joint line is thickened,hyperintense due to inflamed synovium. FS PD FSE - intermediate signal intensity in synovium. Page 6 of 21
Images for this section: Fig. 1: Axial T2 image showing nodular synovial thickening Page 7 of 21
Fig. 2: Sagittal MRI image showing hypointense synovial nodularity. Page 8 of 21
Fig. 3: T2*GRE image showing areas of blooming due to hemosiderin Page 9 of 21
Fig. 4: T1 sagittal image showing frond like synovium. Page 10 of 21
Fig. 5: T2 FS sequence showing the synovial intensity similar to fat. Page 11 of 21
Fig. 6: Axial T2 Fat sat image showing lipomatous synovial proliferation Page 12 of 21
Fig. 7: x ray knee showing calcified nodules / loose bodies Page 13 of 21
Fig. 8: T2 sagittal image showing multiple hyperintense areas with foci of calcification. Page 14 of 21
Fig. 9: PD FS axial image showing the intra articular loose bodies Page 15 of 21
Fig. 10: x ray knee of a patient with rheumatoid arthritis. Page 16 of 21
Fig. 11: Axial FS PD FSE showing synovial thickening and effusion in a case of rheumatoid arthritis. Page 17 of 21
Fig. 12: Sagittal section showing synovial thcikening,cartilage erosions and effusion Page 18 of 21
Conclusion Pearls : PVNS : hypointense synovial thickening /proliferative masses which show blooming on T2*GRE Lipoma arborescens : frond like T1 hyperintense masses suppressed in FS PD FSE Synovial osteochondromatosis: synovial metaplasia with multiple calcified loose bodies Rheumatoid arthritis : thickened synovium with hyaline cartilage loss, subchondral edema and erosions better seen in PD,PD FSE. Page 19 of 21
Personal information Sanjitha sivasubramanian,coimbatore,tamil Nadu,India Page 20 of 21
References Magnetic Resonance Imaging in Orthopaedics and sports medicinedavid W Stoller,MD Hypointense Synovial Lesions on T2-Weighted Images: Differential Diagnosis with Pathologic Correlation José A. Narváez1, Javier Narváez2 3, Raúl Ortega1, Eugenia De Lama1, Yolanda Roca1 and Noemí Vidal4 American Journal of Roentgenology. 2003;181: 761-769. 10.2214/ ajr.181.3.1810761 D A Ritchie -MR imaging of synovial tumors and tumor like lesions.the british journal of radiology,72(1999) 212-218 Page 21 of 21