[A comparative analysis of standard automated perimetry and short wavelength automated perimetry in early diagnosis of glaucoma].

PURPOSE: To assess the concordance between standard automated perimetry (SAP) and short wavelength automated perimetry (SWAP). To analyze comparatively the early detection and the extent of visual field defects in glaucoma suspects and in early glaucoma.

METHOD: A prospective, randomized study that included 55 patients (107 eyes), glaucoma suspects or with early glaucoma who were randomly subject to both SAP and SWAP; the examinations were repeated at 3 and 6 months in order to establish that the visual field defects were real. The studied parameters were the mean value of MD and PSD in the two techniques, the correlation between the results (global and on patients subgroups), the percentage of patients in which the defects were larger, deeper or new defects were found when examined in SWAP.

RESULTS

There was no statistically significant difference in the MD value between the two methods (-3.42 +/- 5.17 dB in SWAP, -2.83 +/- 4.84 dB in SAP, p = 0.14); the PSD value was significantly higher (p < 0.0001) in SWAP (3.63 +/- 1.36 dB) than in SAP (2.66 +/- 1.97 dB). There was a high correlation of the MD and PSD values between the two techniques; the highest correlation appeared in POAG patients. The SWAP test has evidenced visual field defects in 10.1% of eyes with normal SAP tests and also larger and deeper defects in 18.7% of cases.

CONCLUSIONS

The SWAP and SAP results were concordant; the visual field defects were earlier detected, appeared larger and deeper in SWAP than in SAP.