SITA visual field testing in children.
OBJECTIVE
The Swedish Interactive Thresholding Algorithm (SITA) is a new testing strategy for the Humphrey perimeter. The standard SITA algorithm shortens test time in adults without increasing variability, but its usefulness for detecting field defects in children has not been investigated.


METHODS
We evaluated 92 standard SITA 24-2 visual fields of children, most of whom had various types of optic neuropathies (pediatric idiopathic intracranial hypertension, homonymous defects, bitemporal defects, papilledema from brain tumors), and compared them with 49 full threshold 24-2 fields obtained in similar patients. We evaluated outcome measures of foveal threshold, mean defect, pattern standard deviation, false-negative and false-positive rates, and test time. Five children (9 eyes) had both SITA and full threshold testing (FTT).


RESULTS
The SITA decreased test time by over 50% compared with FTT (12.6 +/- 3.0 minutes vs 6.6 +/- 1.6 minutes [P <.00001]). When patients with field defects were eliminated, the pattern standard deviation was lower with SITA than FTT (P <.002), indicating lower intratest variability of SITA in subjects with normal fields. No detectable difference was observed in the other outcome measures. Subjective analysis of gray-scale fields in patients who underwent testing with the use of both strategies showed marked similarities.


CONCLUSIONS
SITA shortens test time significantly compared with FTT and does so without jeopardizing interpretability. SITA has less intratest variability than FTT and therefore should be better for detecting and following defects. Caution is advised when following a visual field defect unless the same strategy is used for each evaluation. Switching strategies in the absence of a stable field defect is not recommended.
Donahue
S P
SP
Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-8808, USA. sean.donahue@mcmail.vanderbilt.edu
Porter
A
A
D000293:Adolescent; D000465:Algorithms; D002648:Child; D005189:False Positive Reactions; D006801:Humans; D009901:Optic Nerve Diseases / Q000150:complications; D011237:Predictive Value of Tests; D014786:Vision Disorders / Q000175:diagnosis* / Q000209:etiology; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields