title: Useful internal standards for distinguishing infiltrative marrow pathology from hematopoietic marrow at MRI.
abstract: The objective of this study was to establish internal standards on MRI differentiating infiltrative marrow pathology from hematopoietic marrow. The T1-weighted images of 74 patients (51 biopsy-proven; 23 clinical follow-up) were reviewed retrospectively. The relative signal intensity of bone marrow was compared to adjacent skeletal muscle (n = 65) and/or nondegenerated intervertebral disk (n = 53). Twenty foci were hyperintense compared to muscle, of which 17 (85%) cases represented normal red marrow (P < .0001); 45 were isointense or hypointense compared to muscle, of which 44 (98%) represented infiltrative marrow processes (P < .0001). Twelve were hyperintense compared to disk, of which 12 (100%) represented normal red marrow (P < .0001); 41 were isointense or hypointense compared to disk, of which 40 (98%) represented infiltrative marrow processes (P < .0001). On T1-weighted spin-echo MRI, skeletal muscle and intervertebral disk may serve as internal standards for differentiating infiltrative pathology from normal hematopoietic marrow. Marrow lesions that are relatively isointense or hypointense to muscle and/or disk should not be considered normal hematopoietic marrow.
authors.affiliation: Department of Radiology, David Grant Medical Center, Travis AFB CA 94535-1800, USA.
authors.forename: K W
authors.initials: KW
authors.lastname: Carroll
authors.forename: J F
authors.initials: JF
authors.lastname: Feller
authors.forename: P F
authors.initials: PF
authors.lastname: Tirman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D001853:Bone Marrow / Q000033:anatomy & histology* / Q000502:physiology; D001855:Bone Marrow Diseases / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000592:standards*; D007403:Intervertebral Disc / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000592:standards*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity