First Author: S.Koshy UK
Co Author(s): S. Efraimidis H. Eleftheriadis 0 0 0 0 0 0 0 0 0
Back to previous
To report the macular morphology findings in patients with chronic optic neuropathy of various aetiology
King’s College Hospital NHS Foundation Trust, Department of Ophthalmology, Denmark Hill, London, UK
Retrospective case series of Optical Coherence Tomography (OCT) findings of patients with chronic optic neuropathy (ON). All patients underwent a comprehensive clinical examination, blood tests, imaging of the brain and orbits, and electrodiagnostic tests to determine the cause of optic neuropathy. Moreover they had visual fields as well as optic disc and macular spectral domain OCT (Spectralis HRA+OCT, Heidelberg Engineering, Germany).
Seven patients with chronic ON (14 eyes), predominantly female (n=5), with mean age 42.6 years (range from 28 to 68 years) were studied retrospectively. Five patients had idiopathic optic neuropathy, one toxic amblyopia and one compressive ON. The visual acuity ranged from 6/6 to 6/60. All patients, except the one with compressive ON, had abnormal visually evoked potential suggestive of optic nerve pathology. Twelve eyes had temporal optic disc pallor with variable visual field defects (central scotomata, peripheral constriction and non specific scotomata). All eyes had microcysts in the inner nuclear layer (INL) of the macula. These were more prominent in the nasal (100%) than temporal macula (28.57%) and occurred in an annular configuration that was evident in infrared reflectance imaging. The mean central subfield retinal thickness was 256 microns (range 232 to 289) with preservation of the foveal depression in all eyes. All 14 eyes had peripapillary retinal nerve fibre layer thinning (RNFL), particularly temporally.
Macular INL microcysts and peripapillary RNFL thinning are findings which can be seen in patients with chronic ON. This microcystic macular appearance should be differentiated from other causes of macular oedema of similar phenotype including that of X-linked retinoschisis and retinitis pigmentosa. Patients with INL microcysts should be investigated fully with imaging of the brain and the orbits as this may be the result of compressive ON secondary to an intracranial space occupying lesion. An OCT of the disc should be performed in patients with INL microcysts as on occasions the optic disc may have a healthy appearance but the OCT reveals RNFL thinning.