Unknown ( or lesser known) concepts On T1W:
1. View the "Dark side" with suspicion
Dark soft tissue,
not seen on fluid sensitive images,
is likely due to fibrotic lesions.
Examples include De Quervain's tenosynovitis and capsular scarring in the axillary recess.
2.
"Fat is a Friend "
Loss of bright fat signal on T1W sequences around the ligaments is a sign of injury to the ligaments.
Loss of bright fat signal within and around nerves implies impingement by lesions like degenerated disc or invasion by tumors.
Fatty infiltration of muscles especially in the shoulder determines prognosis of cuff repair.
3.
"Blood is thicker than water"
Fat-fluid levels inside the bone or in subperiosteal collections imply intramedullary fat necrosis due to osteomyelitis.
4.
Nerve pathology better delineated on T1 weighted images,
as T1 shows the nerves better
Typical examples include visualization of the pudendal nerve and peroneal nerve.
Especially in cases where the involved nerve does not show bright signal on fluid-sensitive sequences (Fig 13)
5.
Differentiation between different Subchondral pathologies
Subchondral edema and cystic change can occasionally look similar on FS PD /STIR images.
Subchondral cysts appear more well defined on T1 while edema appears poorly defined.
Subchondral insufficiency fractures on T1 are seen as
a.
Incomplete dark lines in subchondral region
b.
Parallel the articular surface or are seen convex.
Avascular necrosis on the other hand on T1 is seen as
a.
Complete dark delineating line (serpiginous or not)
b.
Concave or dome-shaped opposite to the articular surface