The effect of laser unit on photodynamic therapy spot size

Abstract

The used laser unit has a significant effect on PDT spot size in this model. These findings may be important for optimizing PDT of choroidal neovascular lesions.

Intravitreal anti-vascular endothelial growth factor combined with half-fluence photodynamic therapy for choroidal neovascularization in chronic central serous chorioretinopathy

“…An excessive spot size may increase the risk of choriocapillaris closure and hypoxia while treatment with a spot size, which is too small, may not lead to the desired effect. 23 In terms of safety profile, the use of the regimen applied in our study of pro re nata IVR/IVB combined with half-fluence ICGA-guided PDT seems to be promising.…”

“…This has led to promising results in a previous study conducted in our tertiary care center. [16][17][18]22,23 Intravitreal anti-VEGF Patients received 0.5/1.25 mg of IVR/IVB under sterile conditions. Fourteen (82.3%) eyes received IVR and three (17.7%) eyes received IVB on a pro re nata regimen.…”

Half-Fluence Photodynamic Therapy in Acute Central Serous Chorioretinopathy

“…10,26,27 Further focusing on exact spot size determination as done in this study can contribute to this promising results as the spot size is not larger than necessary, which can decrease the risk of choriocapillaris closure and hypoxia. 11,12 In terms of safety profile, the use of this regimen of half-fluence ICGA-guided PDT seems to be promising, because the development of secondary CNV or RPE atrophy was not observed. None of the treated patients experienced visual loss, neither immediately after PDT treatment nor during follow-up, and all 19 eyes (100%) showed an improvement of visual acuity.…”

“…This combination approximates to the most exact spot size without having to add 1,000 mm to the greatest linear dimension of the CSC lesion as a safety margin around the whole lesion preventing over-or undertreatment of the choroidal vasculature. 11,12 Exact calculation of the spot size reduces risk of collateral damage such as choroidal ischemia, retinal atrophy, or development of CNV. Focusing on exact spot size determination as done in this study can clearly contribute to the outcome as treatment with a larger-than-necessary spot size may increase the risk of choriocapillaris closure and hypoxia while treatment with a spot size which is too small may not lead to the desired effect.…”

Half-Fluence Photodynamic Therapy in Chronic Central Serous Chorioretinopathy

“…This led to promising results in a previous study conducted in our tertiary care center. [10][11][12] Exact calculation of the spot size reduces risk of collateral damage such as choroidal ischemia, retinal atrophy, or development of CNV. A larger-than-necessary spot size may increase the risk of choriocapillaris closure and hypoxia, whereas treatment with a spot size that is too small may not lead to the desired effect.…”