Title: Visual fields before and after dilatation of pupils
Author(s): Vasantha Suram
1.ACSR Govt. Medical College, Nellore, Andhra Pradesh, India
Corresponding Author: Dr.Vasantha Suram M.S.(Ophthal) MCEH,FAGS
Assistant Professor,ACSR Govt.Medical College,Nellore, AP, India-524004
Purpose: To compare the changes in the visual fields plotted by standard automated perimetry (SAP) before and after dilation of pupils.
Methods: This is a prospective comparative study. Between November 2013 and October 2014, patients attending the general ophthalmology outpatient clinic of Govt. General hospital,Nellore, for routine ophthalmic examination, who were labeled as normal were examined and findings of visual acuity, proper refraction, pupil size and visual fields by automated perimetry, before and after dilatation were documented. The single field analysis printouts were collected and analyzed.
Results: Thirty five eyes of nineteen subjects were enrolled at general Ophthalmology OPD in GGH with mean age of 22.9 years, ranging from 17 to 35 years. The mean baseline pupil size and dilated pupil size were 3.28 ± 0.46 mm and 7.28 ± 0.86 mm in diameter respectively. There was a statistically significant worsening of the Mean Deviation (MD) with a mean decrease of 0.27 dB (P= 0.001) between the baseline and dilated visual fields. There was a statistically significant worsening of the Mean Deviation (MD) with a mean decrease of 0.27 dB (P= 0.001 ) between the baseline and dilated visual fields.
Conclusion: The present study shows that there was statistically significant worsening of the Mean Deviation (MD) (P = 0.001) after pupillary dilation. There was no statistically significant change in the Pattern Standard Deviation (PSD) and foveal threshold after pupillary dilation. Thus this study emphasizes the importance of consistent pupil diameter in serial visual field testing.