title: The increased signal intensity at the vertebral body endplates after chemonucleolysis demonstrated by magnetic resonance imaging.
abstract: Changes in signal intensity observed by magnetic resonance imaging in the contiguous end plates of injected discs after chemonucleolysis over a period of 2 years in 28 patients were evaluated. These changes appeared to be of two types; a transiently increased signal intensity on T2-weighted images, and a progressively increased signal intensity on T1-weighted images with isointense or hyperintense signal on T2-weighted images. The former appeared within three months and disappeared within 2 years. This change was observed in six patients (21%), whose mean age was higher than that of the other patients. This change correlated with the preinjection state of the affected disc. The latter appeared after 2 years and was accompanied by sclerotic changes on roentgenograms. These changes were observed in five patients (18%). The discs, of which the contiguous end plates showed these changes, did not recover the decreased nuclear signal intensity in four patients. These changes are considered to be a sign of degenerative spondylosis in the treated segment.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Nagoya University, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Kato
authors.forename: T
authors.initials: T
authors.lastname: Ando
authors.forename: N
authors.initials: N
authors.lastname: Kawakami
authors.forename: K
authors.initials: K
authors.lastname: Mimatsu
authors.forename: H
authors.initials: H
authors.lastname: Iwata
mesh_terms: D000328:Adult; D002917:Chymopapain / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology*; D007404:Intervertebral Disc Chemolysis; D007405:Intervertebral Disc Displacement / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D013128:Spinal Osteophytosis / Q000175:diagnosis; D013997:Time Factors
chemical_list: D002917:Chymopapain