jalal jalal shokouhi-m.d. ali akbar ameri-m.d. iranian society of radiology...
TRANSCRIPT
Demonestration
Of
occult fractures
by
MRI
We assessed the utility of MRI in diagosis of occult bone fractures and compared with x – rays. T1 and fat saturation images was the best for this diagnosis " few patients , x – ray CT SCANS , are out of study " .
Subjects consisted 140 patients with MRI and x – ray and x – ray CT " few of them fixed in cast or splint "Result : MRI was so helpful in determining bone marrow signal and minimum edema in the bright T1 signal . MRI can't see compact bone or cortex but because of muscle and bone marrow interfaces FX line can be demonstrated by MRI as a bright line . "compact bone as a dark line "
Because of bone fractures without replasment and diastasis they can't detect by x – ray but MRI is helpful and specifically diagnostic to show delicate fracture line and other complications like adjacent bone marrow edema and fat – fluid level in the adjacent joint spaces. " hemorrhage " MRI also can show other lesions beside fracture,Tendon , menisc and …. Lesions .
MRI is reliable and method of choice for assessing fracture line in the bone and complicated condition in the adjacent joint.Other modalities like x – ray , spiral CT – SCAN can show chip bones in case of replacement and could be also negative for FX. Line but can show fat – fluid in the joint spaces an indirect sign of hidden bone marrow fracture. (opening in to the joint space)
MRI also show soft tissue contusion , dirty fat , hematoma , capsule and tendon damages .
Positive X – ray for FX observed in 17% of cases .There was no negative MRI but negative x – ray observed in 83% of cases .Slice thickness was 5 to 8 mm .
Main cause was trauma and second was osteoporosis .Our study mainly occurred in young age group because of random admission .
Bone marrow is brigh and white in T1 images , by standard T2 images it could be white , bright gray and by fat saturation , it should be dark and black .Mild or small amount of edema in bone marrow looks like a small spot on white doctors wearing and named dirty fat .
MRI has about 100 % specificity and sensitivity for occult
fractures of bone by T1 and fat sat.images .
Because of high trauma incidence in this century , specially in our country and equipped centers and hospitals and high sensitivity of MRI to detect small changes in bone marrow signal and water content , traumatized bone with normal X – ray and unusual clinical complains should be check by MRI for occult or hidden fracture line .
