To evaluate the learning effect at Short-wavelength Automated Perimetry (SWAP) using the Swedish Interactive Threshold Algorithm (SITA) program over the central 24 degrees on patients with ocular hypertension experienced with standard automated perimetry.
Twenty-seven patients underwent 5 SITA SWAP tests at intervals of 5±2 days in a randomized eye. Learning effect was defined as an improvement in results for duration, perimetric indices, foveal sensitivity, Glaucoma Hemifield Test, number of points with a P<5% and <1% in the total, and pattern deviation maps, total, central, paracentral, peripheral, and quadrant sensitivity.
Learning effect was shown for foveal sensitivity (P=0.006, analysis of variance), which was significantly different only between the first (23.0 dB±4.1 dB) and the last test (24.7 dB±3.8 dB, P=0.003, t test) and was not affected by any demographic or ophthalmic characteristics of the population. All the other parameters did not show any significant learning effect.
SITA SWAP is affected by a small learning effect interfering only with the first test, as opposite to full-threshold SWAP program, which previously showed severe learning artefacts. This fact may induce reconsideration of the clinical utilization of SWAP for the early diagnosis of glaucoma.
*G.B. Bietti Foundation for the Study and Research in Ophthalmology, IRCCS, Rome
†Eye Clinic, San Paolo Hospital, University of Milan
‡Department of Ophthalmology, “Tor Vergata” University of Rome, Italy
Reprints: Paolo Fogagnolo, MD, Eye Clinic, San Paolo Hospital, Via di Rudini' 8, 20142 Milano, Italy (e-mail: firstname.lastname@example.org).
Received for publication May 20, 2009
accepted August 9, 2009
Contributions of Authors: design and conduct of the study is by Paolo Fogagnolo, Lucia Tanga, and Francesco Oddone.
Collection, management, analysis, and interpretation of the data: Paolo Fogagnolo, Lucia Tanga, Francesco Oddone, Marco Centofanti, and Luca Rossetti.
Preparation, review, or approval of the manuscript: Paolo Fogagnolo, Lucia Tanga, Francesco Oddone, Marco Centofanti, Luca Rossetti, Nicola Orzalesi, and Gianluca Manni.
Statement about Conformity with Author Information: G.B. Bietti Ethics Committee.