Swedish Interactive Threshold Algorithm for central visual field defects unrelated to nerve fiber layer.
OBJECTIVE
To evaluate the characteristic appearance of induced central visual field defects unrelated to the nerve fiber layer on standard automated perimetry using the Swedish Interactive Threshold Algorithm (SITA), and to compare the findings to the appearance on existing Full Threshold (FT) and FASTPAC (FP) algorithms.


METHODS
Thirty right eyes of 30 healthy young participants were examined using four Humphrey 24-2 program algorithms: FT, FP, SITA-Standard (SS), and SITA-Fast (SF). Central visual field defects were induced using a high-density white opacity filter centered on a plano lens. The test duration, fovea threshold, mean sensitivity (MS), mean deviation (MD), pattern standard deviation (PSD), visual field index (VFI), and defect size and depth were compared among all algorithms.


RESULTS
The mean test duration was 21 % to 71 % shorter (p < 0.01), the fovea threshold 0.9 to 2.6 dB higher (p < 0.05), MS 1.1 to 1.7 dB higher (p < 0.05), MD 0.84 to 1.48 dB higher, PSD 0.33 to 0.60 lower, and VFI 2 % higher (p < 0.05) on SS and SF than on FT and FP. The defect size was approximately four points larger and the defect depth 127 to 156 dB shallower on SS and SF than on FT and FP (p < 0.01).


CONCLUSIONS
Central visual field defects unrelated to the nerve fiber layer were wider and shallower and global indices were higher on SITA than on conventional FT and FP. These findings indicate that careful attention is required when converting from FT and FP to SITA.
Orthoptics and Visual Science, Department of Rehabilitation, School of Allied Health Sciences, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan. hirasawa@kitasato-u.ac.jp.
Kazunori
K
Hirasawa
Orthoptics and Visual Science, Department of Rehabilitation, School of Allied Health Sciences, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
Nobuyuki
N
Shoji
D000328:Adult; D000465:Algorithms; D005189:False Positive Reactions; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D009412:Nerve Fibers / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012684:Sensory Thresholds / Q000502:physiology*; D013548:Sweden; D014786:Vision Disorders / Q000175:diagnosis*; D058609:Visual Field Tests; D014794:Visual Fields; D055815:Young Adult
Central visual field defect; SITA; Standard automated perimetry; White opacity filter