Top

Published in:

01-10-2005 | Original Paper

Interobserver variability in confocal optic nerve analysis (HRT)

Authors: Manuel M. Hermann, David F. Garway-Heath, Christian P. Jonescu-Cuypers, Reinhard O. W. Burk, Jost B. Jonas, Christian Y. Mardin, Jens Funk, Michael Diestelhorst

Published in: International Ophthalmology | Issue 4-5/2005

Abstract

Background/aims To study the observer-related variability of optic nerve head (ONH) measurements using confocal laser scanning tomography (HRT I) in a screening setting.

Methods Six experienced glaucoma specialists independently evaluated 50 ONH topographies from 25 adults using HRT software ver. 2.01 in a masked fashion. ONH topographies were obtained from a cohort study of 882 healthy adults and additionally included one patient with glaucomatous eyes. A glaucoma-screening-like setting was intended. The mean interobserver difference was defined as the mean percentual difference between an observer’s analysis and the mean of all six observers for all eyes and all observers. The interobserver range was calculated for each eye as the percentual difference between the lowest and highest measurement, with the highest measurement as denominator. Additionally, Kendall’s coefficient of rank concordance was assessed for the main HRT parameters.

Results Mean disc area ranged from 1.83 ± 0.49 to 2.21 ± 0.40 mm² (mean interobserver difference: 8.3%; interobserver range: 5–50%; rank concordance: 0.86). The lowest mean interobserver differences were found for mean retinal nerve fibre layer thickness (RNFLT; 6.5%), maximum cup depth (2.9%) and cup shape (6.8%). An increased interobserver range was significantly correlated to a low cup to disc area ratio (r = 0.64, P < 0.0001).

Conclusions The observer-dependent diagnostic variability of HRT measurements can lead to divergent diagnostic evaluation of the ONH in a screening setting. Any HRT software relying on a reference database is exposed to relevant observer-related variability of the disc area. For screening purposes, HRT measurements should be completed by other diagnostic methods to compensate for possible diagnostic uncertainty.

Rohrschneider K, Burk RO, Kruse FE, Volcker HE (1994) Reproducibility of the optic nerve head topography with a new laser tomographic scanning device. Ophthalmology 101(6):1044–1049PubMed

Asawaphureekorn S, Zangwill L, Weinreb RN (1996) Ranked-segment distribution curve for interpretation of optic nerve topography. J Glaucoma 5(2):79–90PubMedCrossRef

Bartz-Schmidt KU, Sengersdorf A, Esser P, Walter P, Hilgers RD, Krieglstein GK (1996) The cumulative normalised rim/disc area ratio curve. Graefes Arch Clin Exp Ophthalmol 234(4):227–231PubMedCrossRef

Wollstein G, Garway-Heath D, Hitchings RA (1998) Identification of early glaucoma cases with the scanning laser ophthalmoscope. Ophthalmology 105(8):1557–1563PubMedCrossRef

Hermann MM, Theofylaktopoulos I, Bangard N, Jonescu-Cuypers C, Coburger S, Diestelhorst M (2004) Optic nerve head morphometry in healthy adults using confocal laser scanning tomography. Br J Ophthalmol 88(6):761–765PubMedCrossRef

Arenas-Archila E, Caycedo-Yunis F, Rodriguez MR (2001) Evaluation and definition of physiologic macro cups with confocal optic nerve analysis (HRT). Int Ophthalmol 23(4–6):239–244PubMedCrossRef

Bartz-Schmidt KU, Jonescu-Cuypers CP, Thumann G, Frucht J, Krieglstein GK (1996) Effect of the contourline on the cup area using the Heidelberg retina tomograph. Klin Monatsbl Augenheilkd 209(5):292–297 GermanPubMed

Burk RO, Vihanninjoki K, Bartke T, Tuulonen A, Airaksinen PJ, Volcker HE, Konig JM (2000) Development of the standard reference plane for the Heidelberg retina tomograph. Graefes Arch Clin Exp Ophthalmol 238(5):375–384PubMedCrossRef

Jonas JB, Schmidt AM, Muller-Bergh JA, Schlotzer-Schrehardt UM, Naumann GO (1992) Human optic nerve fiber count and optic disc size. Invest Ophthalmol Vis Sci 33(8):2012–2018PubMed

10.

Papastathopoulos KI, Jonas JB, Panda-Jonas S (1995) Large optic discs in large eyes, small optic discs in small eyes. Exp Eye Res 60(4):459–461PubMedCrossRef

11.

Janknecht P, Funk J (1994) Optic nerve head analyser and Heidelberg retina tomograph: accuracy and reproducibility of topographic measurements in a model eye and in volunteers. Br J Ophthalmol 78(10):760–768PubMed

12.

Kruse FE, Burk RO, Volcker HE, Zinser G, Harbarth U (1989) Reproducibility of topographic measurements of the optic nerve head with laser tomographic scanning. Ophthalmology 96(9):1320–1324PubMed

13.

Orgul S, Cioffi GA, Bacon DR, van Buskirk EM (1996) Sources of variability of topometric data with a scanning laser ophthalmoscope. Arch Ophthalmol 114(2):161–164PubMed

14.

Garway-Heath DF, Rudnicka AR, Lowe T, Foster PJ, Fitzke FW, Hitchings RA (1998) Measurement of optic disc size: equivalence of methods to correct for ocular magnification. Br J Ophthalmol 82(6):643–649PubMed

15.

Wollstein G, Garway-Heath DF, Fontana L, Hitchings RA (2000) Identifying early glaucomatous changes. Comparison between expert clinical assessment of optic disc photographs and confocal scanning ophthalmoscopy. Ophthalmology 107(12):2272–2277PubMedCrossRef

16.

Boros AS, Jonescu-Cuypers CP, Bartz-Schmidt KU (2001) Variability of the normalised rim/disc area quotient estimated by laser scanning tomography. A comparison with conventional planimetry. Int Ophthalmol 24(5):263–267PubMedCrossRef

17.

Iester M, Mikelberg FS, Courtright P, Burk RO, Caprioli J, Jonas JB et al (2001) Interobserver variability of optic disk variables measured by confocal scanning laser tomography. Am J Ophthalmol 132(1):57–62PubMedCrossRef

18.

Jonescu-Cuypers CP, Thumann G, Hilgers RD, Bartz-Schmidt KU, Krott R, Krieglstein GK (1999) Long-term fluctuations of the normalised rim/disc area ratio quotient in normal eyes. Graefes Arch Clin Exp Ophthalmol 237(3):181–186PubMedCrossRef

19.

Chauhan BC, McCormick TA, Nicolela MT, LeBlanc RP (2001) Optic disc and visual field changes in a prospective longitudinal study of patients with glaucoma: comparison of scanning laser tomography with conventional perimetry and optic disc photography. Arch Ophthalmol 119(10):1492–1499PubMed

20.

Garway-Heath DF, Poinoosawmy D, Wollstein G, Viswanathan A, Kamal D, Fontana L et al (1999) Inter- and intraobserver variation in the analysis of optic disc images: comparison of the Heidelberg retina tomograph and computer assisted planimetry. Br J Ophthalmol 83(6):664–669PubMedCrossRef

21.

Swindale NV, Stjepanovic G, Chin A, Mikelberg FS (2000) Automated analysis of normal and glaucomatous optic nerve head topography images. Invest Ophthalmol Vis Sci 41(7):1730–1742PubMed

22.

Chrastek R, Wolf M, Donath K, Niemann H, Paulus D, Hothorn T et al (2005) Automated segmentation of the optic nerve head for diagnosis of glaucoma. Med Image Anal 9(4):297–314PubMedCrossRef

Title: Interobserver variability in confocal optic nerve analysis (HRT)
Authors: Manuel M. Hermann
David F. Garway-Heath
Christian P. Jonescu-Cuypers
Reinhard O. W. Burk
Jost B. Jonas
Christian Y. Mardin
Jens Funk
Michael Diestelhorst
Publication date: 01-10-2005
Publisher: Kluwer Academic Publishers
Published in: International Ophthalmology / Issue 4-5/2005
Print ISSN: 0165-5701
Electronic ISSN: 1573-2630
DOI: https://doi.org/10.1007/s10792-006-9022-9

At a glance: The STEP trials

Springer Medicine

Interobserver variability in confocal optic nerve analysis (HRT)

Abstract

At a glance: The STEP trials

Springer Medicine

Abstract

Please log in to get access to this content

Other articles of this Issue 4-5/2005

Transpupillary thermotherapy for myopic choroidal neovascularization: 1-year follow-up

Retinal break following an intravitreal triamcinolone acetonide injection

Light and electron microscopic studies on human retinal blood vessels of patients with sclerosis and hypertension

Clear corneal incision leakage after phacoemulsification––detection using povidone iodine 5%

Progressive myopia due to posterior staphyloma in type I osteogenesis imperfecta

Prevalence and causes of blindness and visual impairment among school children in south-western Nigeria