Detection and quantification of retinal nerve fiber layer thickness in optic disc edema using stratus OCT.

OBJECTIVE

To investigate the ability of optical coherence tomography (OCT) to assess changes in retinal nerve fiber layer (RNFL) thickness in optic disc edema.

METHODS

Prospective observational case series in a private eye clinic (Centro Salus). Twelve consecutive eyes (9 patients) with optic disc edema were analyzed, including 6 patients with anterior ischemic optic neuropathy, 1 patient with multiple sclerosis-associated papillitis, and 2 patients with bilateral papilledema. Peripapillary scans of the RNFL were obtained using Stratus OCT (software version 3.0; Carl Zeiss Meditec, Dublin, Calif). Repeated measurements were performed in 7 patients during a follow-up ranging from 8 to 30 weeks. The main outcome was RNFL thickness measurement.

RESULTS

Optical coherence tomography detected and quantified diffuse thickening of the RNFL. Compared with eyes in a control group of 75 healthy subjects, eyes with optic disc edema showed a significant increase in the mean RNFL thickness in all quadrants (temporal, P = .002; superior, P<.001; nasal, P<.001; and inferior, P<.001). In patients who were followed up, progressive thinning was observed as the disease evolved toward optic atrophy or clinical resolution.

CONCLUSIONS

Optical coherence tomography can identify and measure RNFL edema. This ability of OCT may help elucidate pathophysiological mechanisms in optic disc edema and provide a valuable aid to clinicians.