The Ability of Short-Wavelength Automated Perimetry to Predict Conversion to Glaucoma
Presented in part at: Dutch Ophthalmological Society Annual Meeting, April 2008, Maastricht, The Netherlands; Association for Research in Vision and Ophthalmology Annual Meeting, April 2008, Fort Lauderdale, Florida.
Received 23 January 2009; received in revised form 27 May 2009; accepted 22 June 2009. published online 06 November 2009.
Purpose
Short-wavelength automated perimetry (SWAP) has been claimed to predict conversion to glaucoma 3 to 4 years before standard automated perimetry (SAP) defects occur. This study compared the moment of glaucomatous conversion between SWAP and SAP.
Design
Prospective, longitudinal follow-up study.
Participants
Four hundred sixteen subjects with ocular hypertension (intraocular pressure ≥22 and ≤32 mmHg and normal visual fields).
Methods
A Humphrey Field Analyzer (24-2 program; Carl Zeiss Meditec, Dublin, CA) was used to perform both SWAP and SAP. All participants were tested once every half year during 7 to 10 years or until the onset of conversion (study end point). The conversion to glaucoma was defined as a reproducible glaucomatous visual field defect in SAP.
Main Outcome Measures
The moment of onset of a reproducible defect in SAP was compared with that in SWAP.
Results
Of the 416 initial participants, 24 eyes of 21 subjects showed conversion in SAP. Of these eyes, 22 did not show earlier conversion in SWAP than in SAP. Standard automated perimetry even showed earlier conversion than SWAP in 15 cases. In only 2 eyes did SWAP show earlier conversion by up to 18 months.
Conclusions
These results do not support the notion that SWAP generally predicts conversion to glaucoma in SAP. Instead, SAP appears to be at least as sensitive to conversion as SWAP in a large majority of eyes.
Financial Disclosure(s)
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Available online: November 6, 2009.
1Glaucoma Service, The Rotterdam Eye Hospital, Rotterdam, The Netherlands
2Department of Ophthalmology, Amphia Hospital, Breda, The Netherlands
Correspondence: Josine van der Schoot, MD, Glaucoma Service-ROI, The Rotterdam Eye Hospital, P. O. Box 70030, NL-3000 LM Rotterdam, The Netherlands
Manuscript no. 2009-106.
Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Supported in part by The Rotterdam Eye Hospital Research Foundation, Rotterdam, The Netherlands; Alcon Laboratories, Inc., Fort Worth, Texas (partly financial support, partly donation of drugs); Merck & Co., Inc., Whitehouse Station, New Jersey (financial support for several years). The sponsors or funding organizations had no role in the design or conduct of this research. The opinions expressed in this paper are those of the authors and do not necessarily represent those of the sponsors.
ABSTRACT