Abstract
Purpose: :
To determine the reproducibility of a new optic nerve and sectoral neuroretinal rim damage assessment scale that utilizes indirect slit-lamp ophthalmoscopy with either a 60D or 66D lens, in patients with glaucoma.
Methods: :
A retrospective review was carried out on 14 randomly chosen charts of glaucoma patients who met the below criteria. A trained glaucoma specialist (RF) performed optic nerve assessment with indirect slit-lamp ophthalmoscopy in patients with dilated pupils utilizing either a 60 D or 66 D lens. The masked assessment of the optic nerve was done without any previous records or any tests being available to the examiner (as these patients’ charts were not available due to recent hurricane damage). The maximal CDR-V was defined as the largest vertical ratio observed (rather than simply being the disc midline value as is usually measured), and the CDR-H was correspondingly defined. The superotemporal (ST), temporal (T), and inferotemporal (IT) rim thinning was recorded and graded as trace (0.5), mild (+1), moderate (+2), marked (+3) or severe (+4) in each eye. This 1-4 scale is commonly used and accepted in many other areas in medicine.After the charts became available (post-hurricane damage restoration) the masked optic nerve assessments were compared to the prior assessments. The absolute value of the differences was calculated.
Results: :
The mean difference in the ST, T and IT neuroretinal rim thinning between the two examinations was 0.56 ± 0.63 (P=0.32), 0.68 ± 0.49 (P=0.31), and 0.64 ± 0.60 (P=0.37) respectively. The mean difference in CDR-V and CDR-H between the two exams was 0.04 ± 0.04 (95% CI: 0.03 to 0.05, P=0.48) and 0.06 ± 0.11 (95% CI: 0.04 to 0.08, P= 0.29) respectively. The average follow up period between the two visits was 11 ± 7.2 months (range, 5-27 months). The mean IOP was within ± 1 mmHg of the mean target IOP in both eyes for the two visits.
Conclusions: :
Our results demonstrate that the sectoral neuroretinal rim damage assessment scale and maximal cup/disk ratios in patients with glaucoma can be assessed in a very reproducible manner by a careful clinical examination with an indirect slit-lamp ophthalmoscopy using either a 60D or 66 D lens.
Keywords: optic nerve • optic disc