The nerve fibre layer symmetry test: computerized evaluation of human retinal nerve fibre layer thickness as measured by optical coherence tomography

Research output: Contribution to journalArticle


Purpose: To present and test a new interpretative concept, the nerve fibre layer symmetry test (NST), for computerized evaluation of retinal nerve fibre layer thickness (RNFLT) as measured by optical coherence tomography (OCT) in glaucoma. Methods: The NST concept was constructed and tested in a pilot study. A total of 32 healthy and 40 age-matched glaucomatous eyes were included and examined by OCT, computerized perimetry, RNFL/disc photography, tonometry and a general ophthalmologic examination. Results: The observed NST sensitivity and specificity were high, at 38/40 eyes (95%) and 32/32 eyes (100%), respectively, and 40/40 eyes (100%), and 31/32 eyes (97%), respectively, when correcting the OCT RNFLT measurement for the influence of variability in image signal/quality. The NST sensitivity was 8-10% higher than the single most sensitive traditional OCT RNFLT parameter; this difference was not statistically significant in this small sample. Conclusion: The NST showed high specificity and sensitivity for detection of RNFLT attenuation indicating early to severe glaucoma. Although promising, the NST needs to be further developed and validated in larger study samples and in patients with various stages of glaucomatous damage.


External organisations
  • University of Copenhagen
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ophthalmology


  • automated analysis, optical coherence tomography, diagnosis, retinal nerve fibre layer, glaucoma
Original languageEnglish
Pages (from-to)410-418
JournalActa Ophthalmologica Scandinavica
Issue number4
Publication statusPublished - 2004
Publication categoryResearch