Transient reduction in retinal function revealed by multifocal electroretinogram after photodynamic therapy

This study was presented in part at the 2002 Annual Meeting of the Association for Research in Vision and Ophthalmology (ARVO), Fort Lauderdale, Florida.
https://doi.org/10.1016/j.ajo.2003.11.079Get rights and content

Abstract

Purpose

To evaluate the early changes in retinal function after photodynamic therapy (PDT) by multifocal electroretinogram (mfERG).

Design

Prospective interventional case series.

Methods

Seventeen eyes from 17 patients scheduled for standard PDT with verteporfin were prospectively recruited. Patients' diagnoses included choroidal neovascularization (CNV) secondary to age-related macular degeneration, idiopathic CNV, myopic CNV, polypoidal choroidal vasculopathy, and central serous chorioretinopathy. Serial mfERG recordings were performed before PDT, and at 4 days, 2 weeks, and 1 month after PDT. The first-order kernel N1 and P1 mfERG response from the central 0 to 7 degrees and peripheral 7 to 25 degrees were grouped and analyzed. The mean response amplitudes and peak latencies of the mfERG recordings were compared longitudinally.

Results

There were statistically significant reductions in the mean N1 response amplitude for the central group at 4 days (P = .007) and 2 weeks after PDT (P = .024), in the mean P1 response amplitude for both the central (P = .006) and peripheral (P = .013) groups at 4 days, and for the central group at 2 weeks after PDT (P = .017). There were also statistically significant increases in the mean P1 response latencies at 4 days (P = .004) and at 2 weeks (P = .018) after PDT for the central group and at 4 days after PDT (P = .026) for the peripheral group. At 1 month after PDT, no significant differences in the N1 and P1 mean response amplitudes and peak latencies were observed compared with pre-PDT mfERG.

Conclusions

Transient impairments in retinal function for as long as 2 weeks after PDT were noticed by reduction in response amplitudes and a delay in peak latencies of mfERG. These findings may explain the common adverse event of subjective visual disturbance early after PDT with normal findings in visual acuity and ophthalmoscopy.

Section snippets

Subjects

We prospectively recruited patients with various macular disorders, including CNV due to age-related macular degeneration, myopic CNV, idiopathic CNV, polypoidal choroidal vasculopathy, and central serous chorioretinopathy who were scheduled for the first PDT. Photodynamic therapy was carried out in the patients with symptomatic polypoidal choroidal vasculopathy due to serous neurosensory retinal detachment, serous pigment epithelial detachment, or subretinal hemorrhage, and in patients with

Patient demographics and pdt application

A total of 17 eyes from 17 patients (12 male, 5 female) who were scheduled for PDT were recruited (Table 1). The mfERG recordings were performed in all patients before PDT, and at 4 days, 2 weeks, and 1 month after PDT. An example of a patient's mfERG recordings is displayed in Figure 1. The mean age of the patients was 50.5 years (range, 29 to 75). Four patients (23.5%) had a diagnosis of idiopathic CNV, four (23.5%) had myopic CNV, four (23.5%) had polypoidal choroidal vasculopathy, three

Discussion

Transient visual disturbances or severe visual losses are some of the adverse events that may occur early after PDT. In the VIP study, 10 (4.4%) of the 225 patients suffered severe visual loss (loss of visual acuities of at least 4 lines or 20 letters) within 7 days after PDT, in which 6 (2.6%) had no obvious causes or findings on clinical examination.3 Subjective visual disturbances were also reported in 42% of patients in the verteporfin-treated group.3 Similar transient visual disturbances

Supplementary files

References (28)

  • Photodynamic therapy of subfoveal choroidal neovascularization in age-related macular degeneration with verteporfin. Two-year results of 2 randomized clinical trialsTAP report 2

    Arch Ophthalmol

    (2001)
  • Verteporfin therapy of subfoveal choroidal neovascularization in age-related macular degenerationtwo-year results of a randomized clinical trial including lesions with occult with no classic choroidal neovascularization: verteporfin in photodynamic therapy report 2

    Am J Ophthalmol

    (2001)
  • Photodynamic therapy of subfoveal choroidal neovascularization in pathologic myopia with verteporfin1-year results of a randomized clinical trial. VIP report no. 1

    Ophthalmology

    (2001)
  • K.J. Blinder et al.

    Verteporfin therapy of subfoveal choroidal neovascularization in pathologic myopia2-year results of a randomized clinical trial. VIP report no. 3

    Ophthalmology

    (2003)
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