Abstract
Purpose: :
A hypoperfusion of the choriocapillaries has been reported beneath the site of the PDT in clinical studies. We evaluated choriocapillaris hypoperfusion following combined verteporfin photodynamic therapy (PDT) with posterior subtenon injection of triamcinolone acetonide (TA) or with intravitreal injection of bevacizumab (IVB) for aged-related macular degeneration (AMD).
Methods: :
Two hundred and thirty-three eyes with a subfoveal choroidal neovascularization (CNV) due to AMD were studied. Ninety-two eyes underwent PDT alone, and 90 eyes underwent PDT with posterior subtenon injection of TA (STTA), and 51 eyes underwent PDT with IVB. PDT alone group and PDT with combined therapy groups were collected at different times, and all cases were consecutive. The intensity of the diffuse fluorescence within the region of the PDT spot except the CNV lesion and the normal retina peripheral to the disc were measured by densitometry (Topcon IMAGEnet computer system) in the indocyanine green angiograms obtained at 10 minutes 3 months after the PDT. The ratio of averaged brightness of the retina within the PDT area to that of the retina peripheral to the disc (irradiation/normal retina brightness ratio=I/N brightness ratio) was calculated for each angiogram.
Results: :
The I/N brightness ratios of the angiograms were 0.96±0.11 in the PDT alone group, 0.85±0.13 in the STTA-PDT group, and 0.89±0.10 in the IVB-PDT group (Kruskal-Wallis H test P<0.05). The I/N brightness ratios of the STTA-PDT group and the IVB-PDT group were lower than that of the PDT alone group (Tukey-Kramer test P<0.05).
Conclusions: :
Subtenon TA and intravitreal bevacizumab may promote short-term choriocapillaris hypoperfusion after PDT.
Keywords: age-related macular degeneration • photodynamic therapy • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)