Detection of changes of the optic disc in glaucomatous eyes: Clinical examination and image analysis with the Topcon Imagenet system

Abstract

ABSTRACT.Purpose: This study was designed to evaluate the clinical agreement in the detection of optic disc changes and the ability of computerized image analysis to detect glaucomatous deterioration of the optic disc. Methods: Pairs of stereophotographs of 35 glaucomatous optic discs taken 5 years apart and of 5 glaucomatous discs photographed twice on the same day. Two glaucoma specialists examined the pairs of stereophotographs (35 cases and 5 controls) in a masked manner and judged whether the optic disc showed changes in the optic disc compatible with progression of glaucomatous damage. The stereophotographs of the five optic discs photographed twice on the same day (which by definition did not change) and of five cases judged to have deteriorated by both glaucoma specialists were analyzed by computerized image analysis with the Topcon ImageNet system. Intra-and inter-observer agreement in the detection of optic disc changes (evaluated using kappa statistic), and changes in the rim area to disc area ratio (evaluated using descriptive statistics and paired t-test). Results: Intra-observer agreement had a kappa value of 0.75 for observer 1 and 0.60 for the observer 2. Inter-observer agreement between the glaucoma specialists had a kappa value of 0.60. The image analyzer did not discriminate between controls and cases with clinically apparent glaucomatous change of the optic disc. Conclusion: Clinical agreement in detecting changes in the optic disc was moderate to substantial. Computerized image analysis with the Topcon ImageNet system appeared not to be useful in detecting glaucomatous changes of the optic disc.

The Quality of Reporting of Diagnostic Accuracy Studies in Glaucoma Using Scanning Laser Polarimetry

“…Current glaucoma diagnosis relies upon the qualitative evaluation of the optic disc and is dependent on the experience of the observer. 36,37 SLP has the theoretical advantage of providing an objective, user friendly, and quantitative assessment of structural damage. This has a promising role in the diagnosis, monitoring, and perhaps screening of glaucoma.…”

Optic Disc Progression in Glaucoma: Comparison of Confocal Scanning Laser Tomography to Optic Disc Photographs in a Prospective Study

“…The agreement between expert observers determining optic disc progression with conventional photography varies among the published reports. 21,26,[32][33][34] In our study, the agreement among the four observers making independent classifications was only fair according to the descriptors proposed by Landis and Koch. 27 There was a large variation in the observer specificity; however, there was a relationship between specificity and hit rate.…”

Validity and reliability of eye healthcare professionals in the assessment of glaucoma - a systematic review

“…Table 2 illustrates the characteristics of the 32 articles that underwent data extraction for this review. Fifteen used optic disc photographs as the measurement tool (17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31), five used visual fields (32)(33)(34)(35)(36), two ophthalmoscopy (37,38), six compared findings from a clinical examination (39)(40)(41)(42)(43)(44) and the remaining four used a combination of either optic disc photographs, visual fields, HRT or scanning laser polarimetry (45,46). The study setting was not specified in a large proportion of articles.…”

“…Very few studies gave a specific classification for their diagnosis of glaucoma, with 17 studies noting that subjects had glaucoma but gave no classification (18,20,22,25,32,35,36,(38)(39)(40)(41)(42)(43)(44)(45)(46). Seven studies included glaucoma subjects who had glaucomatous field loss (17,18,21,28,29,35,36) one study classified their subjects as having glaucoma with early to moderate disc damage (19) and three gave the classification of OAG (26,32,33). In the remaining studies, only glaucoma suspects (39) were used or it was unclear (23,25,31) as to what classification the subjects were.…”

“…The majority (85%) of studies demonstrated positive results of at least moderate to substantial agreement for inter-and intra-rater reliability when diagnosing glaucoma and/ or monitoring progression across all testing modalities. Glaucoma specialists consistently attained the greatest agreement followed by general ophthalmologists (17)(18)(19)(20)(23)(24)(25)(26)(27)(29)(30)(31)(32)(33)(34)(35)37,39,47). When optometrists with different levels of training were compared, those who had completed additional training were significantly better than those who had not (22,28).…”