We evaluated the 78 diopter (D) lens and Zeiss 4-mirror lens for the measurement of vertical and horizontal optic disc diameters during slit-lamp biomicroscopy and compared the results with the measurements made with the computerized image analysing system (IMAGEnet 640, Topcon, Japan) in 30 eyes of 30 patients. The 78D lens and Zeiss 4-mirror lens measurements both correlated well with the computerized image analysis measurements (r=0.881 for vertical and r=0.895 for horizontal disc diameter measurements with the 78D lens and r=0.883 for vertical and r=0.891 for horizontal disc diameter measurements with the Zeiss 4-mirror lens). The 78D lens measurements overestimated vertical disc diameter by 5.3% and horizontal disc diameter by 4.4%. The Zeiss 4-mirror lens underestimated the vertical disc diameter by 2.4% and horizontal disc diameter by 2.2%. Thus either lens can be used for a quick estimation of the optic disc size, since the results correlate well with the computerized image analysis measurements.
JonasJ.B., KonigsreutherK.A., MontgomeryD.M.I.Calculation of the optic disc and cup area by the minimal and maximal diameters.Br J Ophthalmol1994; 78: 510.
2.
JonasJ.B., FernandezM.C., NaumannG.O.H.Correlation of the optic disc size to glaucoma susceptibility.Ophthalmology1991; 98: 675–80.
3.
O'ConnorD.J., ZeyenT., CaprioliJ.Comparison of methods to detect glaucomatous optic nerve damage.Ophthalmology1993; 100: 1498–503.
4.
VarmaR., SpaethG.L., SteinmannW.C., KatzL.J.Agreement between clinicians and an image analyzer in estimating cup-to-disc ratios.Arch Ophthalmol1989; 107: 526–9.
5.
TsaiS., RitchR., ShinD.H., WanJ.Y., ChiT.Age-related decline of disc rim area in visually normal subjects.Ophthalmology1992; 99: 29–35.
6.
VarmaR., SteinmannW.C., ScottI.U.Expert agreement in evaluating the optic disc for glaucoma.Ophthalmology1992; 99: 215–21.
7.
ZangwillL., ShakibaS., CaprioliJ., WeinrebR.N.Agreement between clinicians and a confocal scanning laser ophthalmoscope in estimating cup/disc ratios.Am J Ophthalmol1995; 119: 415–21.
8.
ChiT., RitchR., SticlerD., PitmanB., TsaiC., HsiehF.Y.Racial differences in optic nerve head parameters.Arch Ophthalmol1989; 107: 836–9.
9.
CaprioliJ., MillerJ.M.Optic disc rim area is related to disc size in normal subjects.Arch Ophthalmol1987; 105: 1683–5.
BengtssonB.The variation and covariation of cup and disc diameters.Acta Ophthalmol (Copenh)1976; 54: 804–18.
15.
MongtomeryD.M.I.Clinical disc biometry in early glaucoma.Ophthalmology1993; 100: 52–6.
16.
PapastathopoulosK., JonasJ.B.Ophthalmoscopic measurement of the optic disc.Ophthalmology1995; 102: 1102–6.
17.
RubenS.Estimation of the optic disc size using indirect biomicroscopy.Br J Ophthalmol1994; 78: 363–4.
18.
MontgomeryD.M.I.Measurement of optic disc and neuroretinal rim areas in normal and glaucomatous eyes; a new clinical method.Ophthalmology1991; 98: 50–9.
19.
SpencerA.F., VernonS.A.Optic disc measurements with the Zeiss four-mirror contact lens.Br J Ophthalmol1994; 78: 775–80.
20.
ShirakashiM., NanbaK., IwataK.Changes in reversal of cupping in experimental glaucoma; longitudinal study.Ophthalmology1992; 99: 1104–10.
21.
VarmaR., SpaethG.L., SteinmannW.C., WilsonR.P.Variability in digital analysis of optic disc topography.Graefes Arch Clin Exp Ophthalmol1988; 226: 435–42.
22.
LesterM., TraversoC.E., RolandoM., CalabriaG., ZingirianM.Study of the correlation between average values of optic disc parameters and their measurement variability using stereovideographic digital analysis.Ophthalmologica1995; 209: 177–81.
23.
TomitaG., MatsubaraK., IdoT., KitazawaY.Computerized digital image analysis of optic nerve heads with a three-dimensional image analyzer, IMAGEnet and a comparison with optic nerve head analyzer.Nippon Ganka Gakkai Zasshi1989; 93: 741–6.
24.
SpencerA.F., VernonS.A.Optic disc height measurement with the Zeiss 4-mirror contact lens and 78 Dioptre lens compared.Eye1996; 10: 371–6.
25.
PyottA.A.E., MontgomeryD.M.I.Interobserver variation in clinical optic disc biometry.Eye1993; 7: 452–6.
