Inter-observer variation in clinical optic disc biometry.

A A Pyott; D M Montgomery

doi:10.1038/eye.1993.91

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Inter-observer variation in clinical optic disc biometry.

A A Pyott·D M Montgomery

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Abstract

This study investigated the inter-observer reproducibility of measurements of the optic nerve head as carried out with a clinical optic disc biometer. This instrument employs a modification of indirect ophthalmoscopy to enable measurement of fundus structures. Measurements were made independently by two observers on 84 eyes of 47 patients. The median inter-observer differences for each measurement were as follows: maximum disc diameter, 0.085 mm; minimum disc diameter, 0.080 mm; maximum cup diameter, 0.098 mm; minimum cup diameter, 0.078 mm; disc area, 0.225 mm2; neuroretinal rim area, 0.215 mm2. Utilising the above measurements, the instrument automatically calculates a 'rim index' to take account of variations in disc size. It then interprets the disc as normal, suspicious or glaucomatous. The optic disc biometer produced seriously conflicting interpretations in 8 discs, 7 of which had been judged by both observers to have indistinct boundaries of the disc or cup.

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Biometry Eye Diseases Glaucoma Humans Observer Variation Optic Disk Reproducibility of Results Journal Article

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A A Pyott, D M Montgomery. 1993. Inter-observer variation in clinical optic disc biometry.. https://doi.org/10.1038/eye.1993.91

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