The role of diagnostic imaging from the patient's perspective is to pr
ovide answers to four basic questions:-what is wrong? How bad is it?,
Is it clinically relevant?, Can it be treated? In the assessment of sp
inal disorders, multiple modalities have evolved in an attempt to answ
er the questions poised. Without doubt, the advent of MRI has given th
is process significant benefits primarily because of the unparalleled
way of depicting normal and abnormal tissues in a non-invasive manner.
In particular, MRI is admirably suited to study the intervertebral di
sc and goes a long way in answering the first two questions, aiding in
the accurate analysis of disc morphology, defining pathological state
s, and delineating the extent and effect of disease. This information
however, needs to be equated with the clinical signs and symptoms befo
re any decisions concerning treatment options can be made. At this poi
nt one needs to exercise some degree of prudence and remember that MRI
as yet does not differentiate abnormal asymptomatic from symptomatic
painful disc levels. Enhancement with gadolinium compounds may go some
way in providing some answers by defining the tissue response at or a
round the damaged points within the disco-vertebral unit. Modern MRI s
canners and techniques demonstrate exquisitely, the structural status
of the disc but the functional impact of these structural alterations
cannot as yet be fully determined by MRI-there lies the challenge for
the future. This article reviews the current MRI knowledge concerning
the ageing and herniating intervertebral disc in a clinical context, a
nd critically appraises its present role in a practical fashion. (C) 1
998 Elsevier Science Ireland Ltd. All rights reserved.