|
CT or MRI scans provide accurate information on the extent of eye muscle
enlargement. Successive coronal sections are particularly useful to evaluate
extension of the swollen eye muscles into the apex of the orbit with encroachment
on the optic nerve: such "apical crowding" is a risk factor for the development
of optic neuropathy (Nugent et al. 1988) (Figure 3). Imaging techniques
also appear useful to assess activity of the eye disease: a long T2 relaxation
time in eye muscles and orbital fat on MRI (Just et al. 1991), a low internal
eye muscle reflectivity on A-mode ultrasonography (Prummel et al. 1993),
and a high orbital uptake on octreoscan (Postema et al. 1994) all indicate
active disease. Their accuracy in predicting outcome of immunosuppression
remains to be determined in prospective trials (vide infra).
Figure 3:
|
