Objective To evaluate the effectivness of photodynamic therapy (PDT) with chloroaluminum sulfonated phthalocyanine (CASPc) in B16F10 melanomas in a rabbit model. Methods B16F10 murine melanoma tumor fragments were implanted transclerally into the subchoroidal space of 38 immunosuppressed New Zealand albino rabbits and examined with indirect ophthalmoscopy and ultrasonography. When the tumors ranged from 2.0~3.8 mm in height, 30 rabbits were treated by PDT, with intravenous injection of CASPc 5 mg/kg, and irradiation at the wavelength of 675 nm of an argon-pumped dye laser after 24 hours. Light dose ranged from 20 J/cm2 to 70 J/cm2. The other 8 animals were treated with light only or photosensitizer only. The animals were followed up for 6~8 weeks. Results The 30 tumor-bearing rabbits were by PDT (laser and CASPc) regressed in 21 animals after treatment. At light doses under 40 J/cm2, tumor regrowth was observed in 9 animals after two weeks of treatment. In all of the 8 control animals, the tumor-bearing eyes were filled with tumor at the third week after implantation with laser doses of 70 J/cm2. Conclusion The study suggest that CASPc PDT may be effective in the treatment of B16F10 choroidal melanomas.(Chin J Ocul Fundus Dis，2004，20：67-132)
Objective To investigate the related factors of effects on distant visual acuity after photodynamic therapy (PDT) for choroidal neovascularization (CNV). Methods One hundred and thirty-five cases (135 eyes ) of CNV treated with PDT were observed. The gender, preoperative distant and near visual acuity, disease course, pathogeny, area of CNV, types of CNV ascertained by fundus fluorescein angiography (FFA), and changes of CNV in FFA were recorded. Multi-factor regression analysis of visual acuity within 1 month and 3 months after PDT was performed with SPSS statistics software. Results The distant visual acuity within 1 month postoperatively was related to the preoperative distant visual acuity, the area of CNV and the changes in the FFA（P=0.000,0.030,0.062）, and 3 months after PDT, it was related to the distant and near visual acuity preoperatively and the changes in the FFA（P=0.000,0.054,0.034）. The condition of distant visual acuity within 1 month postoperatively was related to the FFA type of CNV and the disease course（P=0.018,0.08）. Conclusion The smaller the area of CNV is, the better postoperative distant visual acuity would be. The proportion of improvement of visual acuity is relatively higher in patients with classic CNV. Early treatment for the patients with the indicatio may improve the visual acuity effectively. (Chin J Ocul Fundus Dis，2004，20：292-294)
Objective To assess the effects of 670nm LED (lightemitting diode) to protect the photoreceptor from the lightinduced damage in a rat model. Methods 32 SD rats were randomly assigned to one of eight groups: untreated control group, the LEDtreated control group, three groups of lightinduced damage，and three groups of lightinduced damage treated with LED. Lightinduced damage result from exposing to constant light for 3 hours of different illuminations of 900，1800 and 2700 lx, respectively. The LED treatment (50 mW) was delivered for 30 minutes at 3 hours before the light damage and 0，24 and 48 hours after the light damage. Retinal function and morphology were measured by electroretinogram (ERG) and histopathology assay. Results The illumination of 900 lx for 3 hours did not damage the rat retina. The illumination of 1800 lx for 3 hours resulted in thinner ONL and no OS and IS. The ratio of damaged area/total retinal area was 048plusmn;012， the damaged thickness of ONL/normal ONL (L5 ) was 039plusmn;007，and the amplitude of ERG b wave was (431plusmn;120) mu;V. With the LED treatment the ratio of damaged area decreased (M6=017plusmn;0.12, P5/6=0.002), and the ratio of the damaged thickness of ONL also decreased (L6=0.22plusmn;0.09, P5/6lt;0.01), and the amplitude of ERG b wave increased to (1011plusmn;83) mu;V（P5/6lt;0.001）. The illumination of 2700 lx for 3 hours caused severed damage to the rat retina and the LED could not protect them significantly. Conclusions 670 nm LED treatment has an evident protective effect on retinal cells against light-induced damage, which may be a simple and effective therapy to prevent or to delay agerelated macular degeneration.
Objective To evaluate the visual function before and after photodynamic therapy(PDT) in patients with subfoveal choroidal neovascularization ( CNV) caused by age-related macular degeneration (AMD). Methods Twenty-five consecutive patients (34 eyes) treated with PDT (verteporfin) for subfoveal CNV in age-related macular degeneration diagnosed by fluorescein angiography (FFA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT). Visual function including best corrected visual acuity, contrast sensitivity frequency, binocular function, confusion, stereo-vision, color vision, metamorphopsis and central scotoma were examed before photodynamic therapy and 1 week, 1 month, 3 month after photodynamic therapy. The follow-up time varied from 3 months to 2 years (mean 7.6 months). Results The changes of visual function at the 3rd month after photodynamic therapy revealed improving in 13 eyes (38.24%), without any change in 17 eyes (50.00%), and decreasing in 6 eyes (17.65%). Visual acuity with logMRA improved after photodynamic therapy, but without statistic difference. All spatial contrast sensitivity improved. Contrast sensitivity for spatial frequencies 5 cycles per degree (cpd) was better after photodynamic therapy with significant difference (P=0.045).Binocular function, fusion function, stereo function and color vision were slightly improved without statistic difference. Conclusion Damage of visual function in macular degeneration is many-sided. The treatment of PDT for exudative AMD can improve part visual function. (Chin J Ocul Fundus Dis，2004，20：289-291)
Objective To investigate the impact of photodynamic therapy (PDT) with verteporfin on the expression of pigment epithelial derivative factor (PEDF) mRNA and vascular endothelial growth factor (VEGF) mRNA in adult retinal pigment epithelial (RPE) cells in vitro. Methods The changes of cellular viability before and after PDT were assessed by methyl thiazolyl tetrazolum (MTT) colorimetric assay. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was conducted to detect the expression of PEDF and VEGF mRNA in RPE cells before and after PDT. Results PDT caused the death of RPE cells. The cellular mortality was positively correlated with the power of photocoagulation and the concentration of verteporfin. Conclusion PDT could downregulate the expression of PEDF and VEGF mRNA in adult RPE cells in vitro, which may relate to the cure or relapse of subfoveal choroidal neovascular membrane after PDT. (Chin J Ocul Fundus Dis, 2006, 22: 256-260)
Objective To compare the clinical results of photodynamic therapy(PDT) and transpupillary thermotherapy (TTT) for patients with choroidal neovascu larization caused by exudative age-related macular degeneration. Methods Seventy cases (82 eyes) with exudative AMD were divided into PDT and TTT groups. Thirty-five cases (42 eyes) were treated with PDT. Nineteen eyes had occult or predominantly occult CNV. Twenty-three eyes had classic or predominantly classic CNV. Thirty-five cases (40 eyes) were treated with TTT. Twenty-five eyes had occult or predominantly occult CNV. Fifteen eyes had classic or predominantly classic CNV . Visual acuity, FFA, ICGA and OCT were evaluated before and after treatment. All cases were subfoveal or juxtafoveal CNV. The follow-up was 3-6 months. Results Visual acuity in 3 eyes (15.8％) of PDT group and 1 eye (4.0％) in TTT group increased at least 2 lines. The difference was no significant(P=0.1778), FFA showed cessation or reduction of fluorescein leakage from CNV in 15 eyes(78.9％) in PDT group and 13 eyes(52.0％) in TTT group. The difference was not significant (P=0 .0657). Three months after treatment, The visual acuity of 2 eyes(10.5％) in PDT group and 2 eyes (8.0％) in TTT group increased at least 2 lines. The difference was not significant (P=0.7728). FFA showed cessation or reduction of fluorescein leakage from CNV in 8 eyes(42.1％) in PDT group and 21 eyes(84.0％) in TTT group. The difference was significant (P=0.0037). Conclusion For classic CNV, the short-term effect of PDT is better than TTT concerning visual acuity. The effect of PDT is apparently better than TTT in cessation or reduction of fluorescein leakage one month after treatment. But there was no significant difference between PDT and TTT in cessation or reduction of fluorescein leakage three month after treatment. For occult CNV, there is no significant short-term difference between PDT and TTT concerning visual acuity. There was no significant difference between PDT and TTT in cessatin or reduction of fluorescein leakage one month after treatment. But three month after treatment TTT is apparently better than PDT in cessation or reduction of fluorescein leakage. We need more cases and longer follow-up to evaluate these two kinds of treatments in treating exudative age-related macular degeneration.(Chin J Ocul Fundus Dis，2004，20：285-288)