Original article
Effect of cataract extraction on frequency doubling technology perimetry

Presented in part as a poster at the American Academy of Ophthalmology Annual Meeting, Anaheim, CA, November 2003.
https://doi.org/10.1016/j.ajo.2004.03.020Get rights and content

Abstract

Purpose

To investigate the effect of cataract extraction on the results of frequency doubling technology (FDT) perimetry in healthy subjects.

Design

Single-center, prospective, case series.

Methods

We performed FDT threshold C20-1 and Humphrey Swedish Interactive Threshold Algorithm (SITA)–fast programs within 1 month before and 2 months after phacoemulsification in 52 consecutive nonglaucomatous patients. Global indexes, including mean deviation and mean sensitivity of FDT and mean deviation of SITA-fast, were compared before and after cataract surgery. Mean sensitivity of FDT at various visual field grid locations was also compared before and after cataract surgery, as were localized indexes of both FDT and SITA-fast.

Results

Mean deviation improved after cataract surgery in both FDT threshold (from −7.09 dB–−2.16 dB) and SITA-fast program (from −6.14 dB–−2.87 dB). The mean sensitivity at 17 grid locations when the FDT threshold program was used significantly improved postoperatively (from 19.6 dB–26.13 dB). Postoperative improvements in mean sensitivity were also significant at all different sectors, but there were no significant differences of improvement among them. Postoperative pattern standard deviations from FDT and SITA-fast did not differ significantly from their preoperative values.

Conclusions

Cataracts induced a generalized reduction of sensitivity in FDT threshold as well as SITA-fast perimetry. Cataract removal did not change pattern standard deviation of FDT or of SITA-fast. Caution should be taken when interpreting the results of FDT perimetry in the eyes with cataract.

Section snippets

Methods

Subjects were recruited prospectively from the outpatient ophthalmology clinics of the two faculty members (M.S.K. and H.W.T.) at the Asan Medical Center, Seoul, Korea, between October 2002 and September 2003. For each patient with visually important cataracts in both eyes, one eye was chosen at random to be enrolled in the study. Each patient underwent visual field evaluations on two different days within a span of 1 week, occurring 1 month before and 4 to 6 weeks after cataract extraction.

Results

Fifty-two eyes of 52 patients (mean age, 63.9 ± 12.8 years) were entered into the study prospectively. Of these patients, 5 had nuclear sclerotic type cataracts, 10 had cortical type, 7 had posterior subcapsular type, and 30 had mixed type cataracts. Their mean preoperative visual acuity was 0.48 ± 0.2 (range, 0.2–0.7 in logMAR scale), and their mean postoperative visual acuity was 0.11 ± 0.1 (range, 0–0.4 in logMAR scale, P < .0001).

Improvements in mean values of MD were observed by both FDT

Discussion

We have shown here that significant changes in visual field indexes, as measured by both FDT and SITA-fast perimetry, occurred after cataract extraction. Previous studies have shown that media opacity, such as cataract, uniformly depressed white-on-white conventional perimetry, including foveal threshold.10, 11, 12 These findings indicated that cataract extraction resulted in improvement of retinal sensitivity and MD postoperatively, both in glaucomatous and nonglaucomatous eyes.17, 18, 19, 20,

Biosketch

References (35)

  • J.T. Holladay et al.

    Mean visual acuity

    Am J Ophthalmol

    (1991)
  • H.A. Quigley

    Identification of glaucoma-related visual field abnormality with the screening protocol of frequency doubling technology

    Am J Ophthalmol

    (1998)
  • P.P. Chen et al.

    The effects of cataract extraction on the visual field of eyes with chronic open-angle glaucoma

    Am J Ophthalmol

    (1998)
  • M. Iester et al.

    Learning effect, short-term fluctuation, and long-term fluctuation in frequency doubling technique

    Am J Ophthalmol

    (2000)
  • D.H. Kelly

    Frequency-doubling in visual responses

    J Opt Soc Am

    (1966)
  • D.H. Kelly

    Nonlinear visual responses to flickering sinusoidal gratings

    J Opt Soc Am

    (1981)
  • T. Madess et al.

    Performance of nonlinear visual units in ocular hypertension and glaucoma

    Clin Vis Sci

    (1992)
  • Cited by (0)

    Biosketch and/or additional material at www.ajo.com

    View full text