[Axial and para-axial fluorophotometry in optic neuropathies]

To investigate optic neuropathies, with normal results in fluorescein fundus angiography, by axial and paraaxial fluorophotometry (a type of topographic vitreous fluorophotometry) in order to determine differences examined in the amount of fluorescein leakage in macular and optic disc.

We studied 12 eyes with unilateral idiopathic retrobulbar inflammatory optic neuropathy and 4 eyes with unilateral posterior ischaemic optic neuropathy during the acute phase: control group consisted of 5 healthy eyes. After 3-4 months, in final stage of optic neuropathies, in which primary atrophy of optic disc developed (6 eyes), fluorophotometric examinations were repeated. All cases of control group underwent axial and paraaxial fluorophotometry. Complete ophthalmic, physical and neurological examinations were performed.

The mean fluorophotometric values of PVPR (posterior vitreous penetratio-ratio) for f-scans (foveal) were lower than for t-scans (PVPRf < PVPRt) in all neuropathies during the acute phase but all values of PVPR were higher than in control eyes. In late phase of the neuropathies in which primary atrophy of optic disc developed we found a trend: PVPRt < PVPRf, but all values of PVPR were lower than in control eyes. We noticed increased permeability of the blood-ocular barrier and difference between fluorophotometric readings for optic disc directions (t-paraaxial scans) and for foveal directions (f-axial scans) in optic neuropathies during the acute phase, when the findings on ophthalmoscopic and fluorescein fundus angiography were normal.