Agreement of Diagnostic Classification Between Structural Parameters in Pre-Perimetric and Early Perimetric Glaucoma

Abstract

In both pre-perimetric and early perimetric glaucoma, the diagnostic agreements between optic disk, retinal nerve fiber layer, and ganglion cell-inner plexiform layer parameters based on Cirrus HD-OCT normative database classification were mostly fair, suggesting that abnormal classification in 1 anatomic area may suffice for the diagnosis of glaucoma in early stages.Purpose: To evaluate the agreement of normative database diagnostic classification between optic disk, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GCIPL) in patients with early glaucoma.Methods: Retrospective cross-sectional study involving 66 eyes (66 patients) with pre-perimetric and 97 eyes (97 patients) with early perimetric glaucoma. Normative database diagnostic classifications were retrieved from Cirrus HD-OCT scans of 1 eye per participant. An eye was considered abnormal if any of the optic disk, RNFL, or GCIPL was abnormal (yellow or red color-coded classification). For combined parameters, the eye had to be flagged as abnormal by both classifications, regardless of the parameters that were abnormal (global or sectorial). The agreement was assessed with Cohen's Kappa statistics. Results:The agreement between RNFL and GCIPL was fair in both pre-perimetric (κ = 0.25) and perimetric glaucoma (κ = 0.21). Agreements between RNFL or GCIPL and optic nerve head parameters (rim area and vertical cup-to-disk ratio; VCDR) were inconclusive due to insufficient data (P > 0.05). Combining GCIPL and rim area agreed fairly with RNFL both in pre-perimetric (κ = 0.21) and perimetric glaucoma (κ = 0.33). The best classification agreement (moderate) was achieved with the comparison of RNFLrim area versus VCDR (κ = 0.48 in pre-perimetric, 0.45 in perimetric glaucoma). There were no significant differences between pre-perimetric and perimetric glaucoma coefficients of classification agreement. Conclusions:The normative database diagnostic agreements between optic disk, RNFL, and GCIPL were mostly fair in both pre-perimetric and early perimetric glaucoma. Clinicians should not wait for multiple structures to show abnormality on OCT to diagnose early glaucoma.

MP-3 microperimeter in early primary open angle glaucoma with a new pattern

“…The inclusion criteria for the PPG group were: elevated intraocular pressure (IOP; ≥21 mm Hg by Goldmann applanation tonometry) without anti-glaucoma drugs; open angles with gonioscopy; typical glaucomatous optic disc changes: neuroretinal rim thinning, excavation, or notching, increased cupping, and inter-eye cup asymmetry >0.2; and no abnormalities in conventional static perimetry [8] . The early-stage POAG group included patients with elevated IOP (≥21 mm Hg) that were not being treated with anti-glaucoma drugs, with open angles, with gonioscopy, with one of the typical glaucomatous optic disc changes enumerated above, and with VF loss meeting the standard of the Hodapp-Parrish-Anderson classification system: mean deviation (MD) <-6 dB; <25% of the points depressed below the 5% level, and <10 points depressed below the 1% level on the pattern deviation plot; all point in the central 5° must have a sensitivity of at least 15 dB [9] .…”