Abstract
Purpose: :
To evaluate optic nerve circulation changes in patients with corticosteroid–treated (methylpredonisolone) optic neuritis.
Methods: :
The participants in this study are four patients that were diagnosed as having optic neuritis of unknown etiology. All of these four patients received pulsed doses of methylprednisolone.The patients’ ages ranged from 43 to 66 years, with a mean age of 56.25±10.14 (mean±standard deviation (SD)) years. The follow–up period ranged from 6 to 10 months, with a mean follow–up period of 8.25±1.26 (mean±SD) months. The condition of each eye was monitored for at least 6 months. All patients received ophthalmologic examinations including: an intraocular pressure measurement; Goldman perimetry; optical coherence tomography; stereoscopic biomicroscopy; and indirect ophthalmoscopy. The optic nerve circulation was measured with a laser speckle flowgraphy (LSFG) system (Kyushu Institute of Technology, Iizuka, Japan). LSFG was routinely administered before, duringand after the treatment. The quantitative index of relative blood velocity is represented as a normalized blur (NB) or a square blur rate (SBR). The velocity was also measured at the same locations in each patient. A statistical analysis of the data covariance was performed. A P value of 0.05 or less was considered as statistically significant.
Results: :
In three of the four patients, blood flow in the optic nerve head significantly increased during and after the administration of a high dose of intravenous corticosteroid. This blood flow increase resulted in an improvement of visual field. In contrast, the visual field did not improve in one of the four patients whose optic nerve blood flow did not increase. Disc edema decreased in all cases. The systematic blood pressure and intraocular pressure were not significantly affected by the treatment.
Conclusions: :
We have shown that high dosages of intravenous corticosteroid have an effect on the improvement of optic nerve circulation in patients with optic neuritis. We believe that the blood circulation of the optic disc may be related to the recovery process of optic neuritis.
Keywords: optic flow • optic disc • neuro-ophthalmology: optic nerve