The Clinical Researches Of Transpupillary Thermotherapy For Choroidal Neovascularization

ObjectiveTo evaluate the effectiveness and the security of transpupillary thermotherapy for different pathogenies and different types of choroidal neovascularization. Object and Methods32 eyes of 31 cases confirmed as active choroidal neovascularization by clinical examination and fluorescein or indocyanine angiography were involved in the researches. There are 10 eyes of 9 cases secondary to the age-related macular degeneration, 8 eyes of 8 cases in result of pathological myopia and 14 eyes of 14 cases caused by central exudative chorioretinopathy. All cases were received transpupillary thermotherapy with 810nm diode laser. The treatment was initiated with one point for 60 seconds and the spot size was between 0.5mm and 2.0mm. The power levels were between 110 and 450 mW and the power/diameter was between 76.27mW /mm and 277. 78 mW/mm. Best-corrected visual acuity, reading visual acuity, Amsler chart, funduscopy, color fundus photograph, average visual sensitivity of macular, leakage of CNV and the complications were assessed during the follow-up. All the dates were analyzed with SPSS11. 0 software package. Results 1. Best-corrected visual acuities: vision acuity was improved in 9/32(28.1%) and was stabilized in 23/32 (71.9%). Significant difference was found in vision between the pre-TTT and post-TTT with rank sum M-W test (P<0. 05).2. Average visual sensitivity of macular: Average visual sensitivity of macular was improved after TTT. The difference between the pre-TTT and post-TTT was significant with t-test (P<0. 05).3. CNV leakage: 7 eyes (21.9%) had no leakage,15 eyes (46.9%) had less leakage, 5 eyes (15. 6%) had no changes, 3 eyes (9. 4%) had more leakage , 2 eyes (6.3%) recurrented. Significant difference was found in the area of leakage between the pre-TTT and post-TTT with rank sum M-W test (P<0. 001).4. Complications: Retinal hemorrhage was seen in 1 eye during TTT. There were 2 eyes with transitory retinal edema after the treatment and retinal hemorrhage increased in 1 eye.5. The follow-up time: 6. 33 3. 55 months averagely Conclusions1. TTT is effective for the different pathogenies and types of CNV, the visual acuity is improved and the risk of losing visual acuity severely is low.2. TTT may result in less collateral damage to neurosensory retina and average visual sensitivity of macular can be improved, so it is safety for CNV underneath the foveal .3. The adverse effect on visual acuity is slight in TTT. The complications cannot be foretold according to the current experiences.4. The individual difference of the therapeutic parameter of TTT is great. The optimal treatment parameters of sub-photocoagulation is a difficulty and still to be resolved.