Optic nerve head analyser and Heidelberg retina tomograph: accuracy and reproducibility of topographic measurements in a model eye and in volunteers.

The accuracy and reproducibility of the optic nerve head analyser (ONHA) and the Heidelberg retina tomograph (HRT) were compared and the performance of the HRT in measuring fundus elevations was evaluated. The coefficient of variation of three repeated measurements in a model eye and in volunteers and the relative error in a model eye was calculated. With ONHA measurements the pooled coefficient of variation in volunteers was 9.3% in measuring cup areas and 8.4% in measuring the cup volume. In a model eye the pooled coefficient of variation was 7.6% for the parameter 'cup area' and 9.9% for the parameter 'cup volume'. The pooled relative error in the model eye was 6.6% for the parameter 'cup area' and 5.1% for the parameter 'cup volume'. With HRT measurements in volunteers the pooled coefficient of variation of both the parameters 'volume below contour' and 'volume below surface' was 6.9%. In the model eye the pooled coefficient of variation was 2.4% for the 'volume below contour' and 4.1% for the parameter 'volume below surface'. The pooled relative error in the model eye was 11.3% for the 'volume below contour' and 11% for the 'volume below surface'. The pooled relative error in measuring retinal elevations in the model eye was 3.8%. The coefficient of variation was 3.5%. The accuracies of the HRT and ONHA were similar. However, as the ONHA 'cup volume' is unreliable in patients because of the design of the ONHA whereas the HRT volume parameters are reliable it seems reasonable to assume that the HRT is superior to the ONHA. Only the HRT is capable of quantifying retinal elevations.

[1]  J. Tiedeman,et al.  Accuracy of topographic measurements with the Optic Nerve Head Analyzer. , 1989, American journal of ophthalmology.

[2]  R. Weinreb,et al.  Accuracy of topographic measurements in a model eye with the laser tomographic scanner. , 1991, Investigative ophthalmology & visual science.

[3]  J. Funk,et al.  [Improved reproducibility of computer-assisted structural analysis of the optic papilla]. , 1991, Klinische Monatsblatter fur Augenheilkunde.

[4]  U. Klingbeil.  Fundus Geometry Measured with the Analyzing Stereo Video Ophthalmoscope , 1990 .

[5]  M. Wax,et al.  Variability and reproducibility of optic disk topographic measurements with the Rodenstock Optic Nerve Head Analyzer. , 1988, American journal of ophthalmology.

[6]  T. Cornsweet,et al.  Reliability of optic disk topographic measurements recorded with a video-ophthalmograph. , 1984, American journal of ophthalmology.

[7]  R. Burk,et al.  [Comparison of two laser scanning tomography systems for three-dimensional analysis of the optic papilla]. , 1993, Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft.

[8]  G Zinser,et al.  Reproducibility of topographic measurements of the optic nerve head with laser tomographic scanning. , 1989, Ophthalmology.

[9]  R N Weinreb,et al.  Effect of repetitive imaging on topographic measurements of the optic nerve head. , 1993, Archives of ophthalmology.

[10]  U Klingbeil,et al.  Reproducibility of optic disc measurements with computerized analysis of stereoscopic video images. , 1986, Archives of ophthalmology.

[11]  M. B. Shields,et al.  Reproducibility of topographic measurements with the optic nerve head analyzer. , 1987, American journal of ophthalmology.

[12]  Barry R. Masters,et al.  Noninvasive Diagnostic Techniques in Ophthalmology , 1990, Springer New York.

[13]  R N Weinreb,et al.  Reproducibility of topographic measurements of the normal and glaucomatous optic nerve head with the laser tomographic scanner. , 1991, American journal of ophthalmology.