New developments in Heidelberg retina tomograph for glaucoma.
OBJECTIVE
Provides an update on research on Heidelberg retina tomograph (HRT) imaging of the optic nerve head in glaucoma. Particular reference is made to work assessing recently introduced software developments.


RESULTS
Three main areas of investigation are covered: new developments in the third major revision of the HRT operational software (HRT-3), HRT's ability to correctly classify glaucomatous optic neuropathy, and HRT's role in monitoring disease progression. The software now incorporates a larger normative database of white patients as well as new ethnic-specific databases. The main classification tools in the new software are the Moorfields regression analysis and Glaucoma Probability Score. The performance of these classification systems is influenced by the new normative databases. A number of HRT rim area progression strategies has been proposed. These appear to complement visual field progression analyses, identifying a largely different subset of progressing patients. HRT measurement variability has recently been better characterized, and promising methods of improving measurement repeatability have been described.


CONCLUSIONS
The HRT is a promising tool for monitoring patients with, or at risk of, glaucoma, although the relationship between progressive structural and visual field change has yet to be fully elucidated. Each refinement to the instrument software requires evaluation to establish whether it constitutes an improvement in our ability to manage patients.
Strouthidis
Nicholas G
NG
Glaucoma Research Unit, Moorfields Eye Hospital and UCL Institute of Ophthalmology NIHR Biomedical Research Centre, London, UK.
Garway-Heath
David F
DF
D018450:Disease Progression; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D018613:Microscopy, Confocal / Q000295:instrumentation; D019721:Ophthalmoscopes; D009887:Ophthalmoscopy / Q000379:methods*; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D014054:Tomography / Q000379:methods