Cataracts affect RNFL and OCT output

February 2, 2011

The presence of cataracts could influence optical coherence tomography (OCT) signal strength (SS) and peripapillary retinal nerve fibre layer (RNFL) thickness measurements

The presence of cataracts could influence optical coherence tomography (OCT) signal strength (SS) and peripapillary retinal nerve fibre layer (RNFL) thickness measurements, according to a study published in the Journal of Glaucoma.

Dr Jean Mwanza

et al.

, Basom Palmer Eye Institute, University of Miami, Leonard Miller School of Medicine, Miami, Florida, USA, studied 45 cataract patients, 23 of which had glaucoma.

Cataracts were graded with the Lens Opacities Classification System III. Stratus OCT scans were used to measure peripapillary RNFL before and after cataract surgery.

The results revealed a significant postoperative difference in RNFL thickness in patients with a lower preoperative RNFL thickness and SS. The findings also demonstrated no significant difference in RNFL thickness change between cataract patients and patients with both glaucoma and cataract.

The investigation suggests that peripapillary RNFL measurements, especially if SS is weaker, should be interpreted with care in glaucomatous eyes, as cataracts could affect them.