Answer for BIR CoW 14 Jan 2024
ANSWER
Features of Ankylosing spondylitis with Andersson lesion reflecting discovertebral unit instability and spondylodiscitis in D8-D9 and L3-L4 vertebral level.
Findings
Central T2 heterointense signal intensity noted involving the discovertebral unit affecting both vertebral halves of D8-D9 vertebral level with ill defined heterointense enhancement noted in the D8-D9 vertebral level T2 altered signal intensity noted in the discovertebral unit affecting the L3-L4 vertebral level with adjacent T2 heterointensity noted Tiny foci of enhancement seen eccentrically in spinal cord at D8-D9 vertebral level. Reduced joint with sclerosis and irregularity and fusion of bilateral sacroiliac joint in lower one third. Two foci of hyperintensity noted in posterior corner of D7, D11 vertebral bodies reflecting Romana’s lesion. Facetal joint arthrosis noted in D8, D9 and L3, L4 and L5 vertebral level.
Discussion
MRI features of Ankylosing spondylitis Magnetic resonance imaging represents a major advance in the diagnosis of AS in that it enables early detection of disease, when radiographs are normal. Sacroiliac joints: Bilateral sacroillitis synovitis and joint effusions STIR is preferred over T2 fat-suppressed images as it is more sensitive in detecting subchondral bone marrow edema. Spine: Andersson lesions/Discovertebral lesions- are the same as Romanus lesions but are more central in location at the discovertebral junction. -Active lesions can look like Modic type 1 changes of degenerative disc disease, so it is important to search for corner lesions of spondylitis, facet joint involvement, and enthesitis of the posterior ligaments in order to differentiate them . -Edema and enhancement may also be present in the center or throughout the disc, simulating discitis due to infection. Interbody ankylosis marks chronic disease Acute inflammatory Romanus lesion- circumscribed triangular-shaped area of corner edema within the vertebral body that is STIR/ T2-hyperintense and enhances on T1-weighted post-gadolinium images, corresponding to enthesitis at the attachment of the annulus fibrosis to the vertebral body endplate Enthesitis of the anterior and posterior longitudinal ligaments, the posterior ligaments, i.e., the ligamentum flavum , supraspinous and interspinous ligaments are typically involved. sternocostal and costovertebral joints show arthritis manifested by subchondral bone marrow and adjacent soft tissue edema and enhancement, with ankylosis occurring in chronic disease syndesmophytes of chronic disease are difficult to see on MRI due to their thinness and low signal intensity Facet joint arthrosis involvement is manifested by subchondral bone marrow and adjacent soft tissue edema and enhancement, which is usually associated with similar changes in the pedicles Joint effusions and synovial enhancement are additional manifestations of facet arthritis
Features of Ankylosing spondylitis with Andersson lesion reflecting discovertebral unit instability and spondylodiscitis in D8-D9 and L3-L4 vertebral level.
Findings
Central T2 heterointense signal intensity noted involving the discovertebral unit affecting both vertebral halves of D8-D9 vertebral level with ill defined heterointense enhancement noted in the D8-D9 vertebral level T2 altered signal intensity noted in the discovertebral unit affecting the L3-L4 vertebral level with adjacent T2 heterointensity noted Tiny foci of enhancement seen eccentrically in spinal cord at D8-D9 vertebral level. Reduced joint with sclerosis and irregularity and fusion of bilateral sacroiliac joint in lower one third. Two foci of hyperintensity noted in posterior corner of D7, D11 vertebral bodies reflecting Romana’s lesion. Facetal joint arthrosis noted in D8, D9 and L3, L4 and L5 vertebral level.
Discussion
MRI features of Ankylosing spondylitis Magnetic resonance imaging represents a major advance in the diagnosis of AS in that it enables early detection of disease, when radiographs are normal. Sacroiliac joints: Bilateral sacroillitis synovitis and joint effusions STIR is preferred over T2 fat-suppressed images as it is more sensitive in detecting subchondral bone marrow edema. Spine: Andersson lesions/Discovertebral lesions- are the same as Romanus lesions but are more central in location at the discovertebral junction. -Active lesions can look like Modic type 1 changes of degenerative disc disease, so it is important to search for corner lesions of spondylitis, facet joint involvement, and enthesitis of the posterior ligaments in order to differentiate them . -Edema and enhancement may also be present in the center or throughout the disc, simulating discitis due to infection. Interbody ankylosis marks chronic disease Acute inflammatory Romanus lesion- circumscribed triangular-shaped area of corner edema within the vertebral body that is STIR/ T2-hyperintense and enhances on T1-weighted post-gadolinium images, corresponding to enthesitis at the attachment of the annulus fibrosis to the vertebral body endplate Enthesitis of the anterior and posterior longitudinal ligaments, the posterior ligaments, i.e., the ligamentum flavum , supraspinous and interspinous ligaments are typically involved. sternocostal and costovertebral joints show arthritis manifested by subchondral bone marrow and adjacent soft tissue edema and enhancement, with ankylosis occurring in chronic disease syndesmophytes of chronic disease are difficult to see on MRI due to their thinness and low signal intensity Facet joint arthrosis involvement is manifested by subchondral bone marrow and adjacent soft tissue edema and enhancement, which is usually associated with similar changes in the pedicles Joint effusions and synovial enhancement are additional manifestations of facet arthritis
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!