Choroidal thickness at outside laser spot in photodynamic therapy

1. Yukinori Sugano
2. Ichiro Maruko
3. Akira Ojima
4. Hiroshi Oyamada
5. Tetsuju Sekiryu
6. Tomohiro Iida

Fukushima Medical University School of Medicine, Fukushima, Japan

(Purpose)
Subfoveal choroidal thickness decreased after photodynamic therapy (PDT).1) To evaluate choroidal thickness at the area of outside laser spot after PDT in the eyes with central serous chorioretinopathy (CSC) and polypoidal choroidal vasculopathy (PCV) using optical coherence tomography (OCT).

(Methods)
Fourteen eyes with CSC were treated with half-dose verteporfin PDT and sixteen eyes with PCV were treated with standard-dose verteporfin PDT. All lesion areas included the fovea. We measured the choroidal thickness at inside and outside laser spot using OCT. Measurement sites of outside laser spot were 1mm superior, inferior, and temporal points away from edge of irradiation area.

(Results)
Mean subfoveal choroidal thickness significantly decreased from 378±105μm to 300±118μm at 3 months in CSC (p<0.01), and from 275±96μm to 229±85μm at 3 months in PCV (p<0.01). Mean choroidal thickness of outside laser spot significantly decreased from 318±74μm to 282±62μm at 3 months in CSC (p<0.01), and from 263±72μm to 226±68μm at 3 months in PCV (p<0.01). However decreased ratio of choroidal thickness at outside laser spot in PCV (14%) was larger than that in CSC (11%).

(Conclusions)
PDT developed the choroidal thinning at not only inside but also outside laser spot.
1) Maruko I, et al. Ophthalmology, 2010.