title: T2 black lesions on routine knee MRI: differential considerations.
abstract: The majority of abnormal findings or lesions on T2-weighted fast spin-echo (FSE) magnetic resonance imaging (MRI) are hyperintense due to increased perfusion or fluid content, such as infections, tumours or synovitis. Hypointense lesions on T2-weighted images (both fat-suppressed and non-fat-suppressed) are less common and can sometimes be overlooked. Such lesions have limited differential diagnostic possibilities, and include vacuum phenomenon, loose body, tenosynovial giant cell tumour, rheumatoid arthritis, haemochromatosis, gout, amyloid, chondrocalcinosis, hydroxyapetite deposition disease, lipoma arborescens, arthrofibrosis and iatrogenic lesions. These lesions often show characteristic appearances and predilections in the knee. In this article, the authors describe the MRI features of hypointense T2 lesions on routine knee MRI and outline a systematic diagnostic approach towards their evaluation. Key Points • Hypointense lesions on T2 images (T2 Dark Lesions) encompass limited diagnostic possibilities. • T2 Dark lesions often show characteristic appearances and predilections in the knee. • A systematic diagnostic approach will help radiologists make the correct diagnosis.
authors.affiliation: Department of Radiology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: Vibhor
authors.initials: V
authors.lastname: Wadhwa
authors.affiliation: Musculoskeletal Radiology, UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Gina
authors.initials: G
authors.lastname: Cho
authors.affiliation: Musculoskeletal Radiology, UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Moore
authors.affiliation: Musculoskeletal Radiology, UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Parham
authors.initials: P
authors.lastname: Pezeshk
authors.affiliation: Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Coyner
authors.affiliation: Musculoskeletal Radiology, UT Southwestern Medical Center, Dallas, TX, USA. avneesh.chhabra@utsouthwestern.edu.|Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, TX, USA. avneesh.chhabra@utsouthwestern.edu.
authors.forename: Avneesh
authors.initials: A
authors.lastname: Chhabra
mesh_terms: D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007592:Joint Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male
keywords: Arthrofibrosis; Chondrocalcinosis; Chondromatosis; MRI knee; Tenosynovial giant cell tumour