Abstract
Purpose: :
To evaluate the macular function by measuring the focal macular electroretinograms (ERGs) before and after reduced fluence photodynamic therapy (RFPDT) in patients with polypoidal choroidal vasculopathy (PCV).
Methods: :
Eleven eyes of 11 patients with PCV were studied. Their ages ranged from 62 to 85 years with a mean of 74.7 ± 6.9 years. The exposure time for the RFPDT was reduced to 42 sec so that the total energy of the laser was approximately one-half that of the standard PDT. We measured the visual acuity, foveal thickness, and focal macular ERGs before and after the RFPDT. The focal macular ERGs were elicited by a 15° white stimulus spot centered on the macula.
Results: :
The follow-up period ranged from 13 to 34 months with a mean of 26 months after the treatment. A significant recovery of vision was seen even at 1 week after the RFPDT (P<0.005), and the visual acuities improved gradually thereafter (P<0.0005). The foveal thickness was significantly reduced at 1 week after the treatment (P<0.005), and then continued to become significantly thinner with time (P<0.0001). A slight recovery of the a- and b-wave amplitudes was seen postoperatively without a transient reduction of the amplitudes. The b-wave amplitude was significantly larger at 3 months after the treatment than at baseline (P<0.05). Choroidal hypoperfusion did not develop 3 months postoperatively in the indocyanine green angiograms. Exudative changes recurred in 4 (27%) eyes after 1 year and in 9 (82%) eyes during the follow-up period.
Conclusions: :
RFPDT provided short-term benefits in selected patients of PCV with small lesions. The macular function was retained after RFPDT without a transient decrease of visual function. Further study is needed to determine the long-term efficacy of RFPDT for eyes with PCV.
Keywords: electroretinography: clinical • photodynamic therapy • age-related macular degeneration