- The ability of short-wavelength automated perimetry to predict conversion to glaucoma.
The ability of short-wavelength automated perimetry to predict conversion to glaucoma.
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. Prospective, longitudinal follow-up study. Four hundred sixteen subjects with ocular hypertension (intraocular pressure >/=22 and </=32 mmHg and normal visual fields). 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. The moment of onset of a reproducible defect in SAP was compared with that in SWAP. 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. 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. The author(s) have no proprietary or commercial interest in any materials discussed in this article.