Purpose: To evaluate the long-term course of visual field defects after intravitreal injection of indocyanine green (ICG) during vitrectomy.
Methods: Retrospective observational case series. The medical records of seven eyes of seven patients with visual field defects after the adjunctive use of ICG during macular hole surgery were studied. All of the surgeries were performed between February 2001 and January 2002. Humphrey static perimetry and best-corrected visual acuity were examined periodically, and the main outcome measure was the mean deviation (MD) determined by the Humphrey (30-2) SITA-Fast program.
Results: All patients were observed for more than 4.5 years, for a mean of 60.7 months and a range of 54 to 66 months. The preoperative MD was -3.5 +/- 3.1 dB (mean +/- SD), and the postoperative MD was -13.3 +/- 4.9 dB at 1 year, -13.4 +/- 4.6 dB at 2 years, -16.2 +/- 5.1 dB at 3 years, and -15.6 +/- 5.1 dB at 4 years. The decrease in the mean MD between 1 and 3 years after surgery was significant (P < 0.05). Optic disk pallor in five eyes showed a decrease in the MD between 1 year and 3 years after the surgery. There was no significant difference in the postoperative best-corrected visual acuity at any time.
Conclusions: The visual field defect in eyes that had undergone vitrectomy with staining of the internal limiting membrane with ICG can continue to deteriorate for at least 3 years. Eyes receiving intravitreal ICG during vitrectomy should be followed for a longer period to determine the long-term effect of ICG.