光动力学疗法治疗角膜新生血管后角膜的光电镜改变

目的观察应用国产光敏剂行光动力学疗法(PDT)治疗角膜新生血管后角膜的组织学改变。方法碱烧伤有色兔角膜制作角膜新生血管模型。血啉单醚5mg/kg自耳缘静脉注射,不同的能量密度61.2-52.8J/cm2的氲绿激光照射角膜新生血管根部,不注射血啉单醚并单纯行同等能量密度的激光照射组作为对照组,PDT治疗后3h、1周、1个月行角膜光电镜检查。结果PDT后3h可见角膜急性炎症反应,有大量中性粒细胞浸润和少量嗜酸性白细胞浸润,虹膜组织无损伤。PDT后1周角膜炎症反应大部分消失,可见新生血管腔内有无定形物质填塞和许多影子血管。透射电镜显示:PDT组角膜新生血管内皮细胞内线粒体显示出空泡样变,细胞形态不完整。结论血啉单醚作为光敏剂,应用氩绿激光对角膜新生血管行PDT治疗,导致新生血管内皮细胞损伤,能有效封闭角膜新生血管,对周围组织无明显损伤。     

应用血啉甲醚的光动力学疗法治疗实验性虹膜新生血管

目的观察以国产血啉甲醚(HMME)为光敏剂,应用光动力学疗法(PDT)封闭实验性虹膜新生血管(INV)的疗效和并发症。方法应用氩离子激光封闭猴眼全部视网膜分枝静脉的方法建立INV模型。静脉注射HMME(5 mg/kg),用514 nm的氩绿激光照射,设定能量密度分别为107.46、143.28、275.22 J/cm23组,行虹膜彩像、虹膜荧光造影(IFA)、虹膜吲哚青绿造影(IICGA)及光镜和电镜观察疗效。结果PDT治疗后48 h,治疗区INV基本闭塞;ICGA显示基质层血管有不同程度的闭塞。PDT后3周,治疗区域新生血管仍闭塞,虹膜基质血管重新开放;非治疗区新生血管退行。光镜显示中能量组虹膜基质轻度萎缩,高能量组虹膜可见大量色素增殖。治疗组均未发生眼压升高。结论以HMME为光敏剂的PDT在一定时期内可有效封闭实验性虹膜新生血管,减少新生血管性青光眼的发生,但对虹膜基质有一定损伤。     

光动力治疗兔角膜新生血管的研究

目的：观察光动力学治疗(photodynamic therapy,PDT)缝线法诱导的兔角膜新生血管(cornaeal neovascularization,CNV)的效果和安全性。方法：取新西兰白兔5只10眼,用5．0号的丝线在角膜上缝线诱导角膜新生血管的生长,注射光敏剂Photofrin 48h后行DIOMED630PDT激光照射。裂隙灯显微镜观察角膜NV生长情况,并且计算其面积、生长长度,照射后28d处死实验兔,取其眼球做组织病理学检查。结果：角膜缝线后3d开始有新生血管长入,3wk后长到缝线的尖端。激光照射后2d开始角膜新生血管变得模糊不清,2wk后角膜新生血管近完全消失。组织病理学检查见角膜,视网膜以及虹膜、睫状体、脉络膜等组织正常。结论：光动力治疗角膜新生血管有效、安全。     

结膜下注射Avastin抑制角膜新生血管的实验研究

目的:观察结膜下注射Avastin对实验性兔眼角膜新生血管(neovascularization,NV)的抑制作用,初步探讨作用机制。方法:应用5mm直径的加样器(末端附有棉片)吸入1mol/LNaOH接触新西兰兔右眼(20眼)中央角膜区烧灼30s,制作碱烧伤兔眼角膜NV模型。将实验兔随机分成2组,10眼(A组)碱烧伤后立即结膜下注射Avastin 2.5mg;其余10眼为对照组(B组),结膜下注射等量生理盐水。烧灼后次日每天裂隙灯观察角膜NV、角膜水肿情况,分别于3,7,14,21,28d裂隙灯照相并计算NV面积及NV抑制率。伤后7,28d各组随即处死5只实验兔,取角膜组织做石蜡切片行组织病理学检查及VEGF免疫组织化学检测。结果:两组兔眼伤后第1d角膜缘血管网明显扩张充血,3d时血管开始侵入角膜,7～14d时NV达到高峰,14～21d后NV稳定并逐渐回退。两组角膜NV长度、NV面积及角膜水肿程度存在差异(P<0.05);A组各时间点角膜NV抑制率为44.2%～55%。A组角膜上皮及实质层水肿较轻,NV较少,后弹力层基本完整,VEGF表达明显弱于B组。结论:结膜下注射Avastin对碱烧伤诱导的兔眼角膜NV形成及生长具有明显的抑制作用,可能通过下调VEGF表达发挥作用。     

医用几丁糖对角膜碱烧伤后新生血管的抑制作用

目的观察医用几丁糖对角膜碱烧伤后新生血管的抑制作用。方法NaOH烧伤兔角膜制作角膜碱烧伤模型,随机分为碱烧伤组（碱烧伤）和几丁糖组（碱烧伤＋2％医用几丁糖滴眼）。分别于1、4．7、14d观察两组兔角膜新生血管生长情况,HE染色计算多形核粒细胞（PMN）数量,兔疫组化染色测定血管内皮生长因子（VEGF）的活性。结果几丁糖组新生血管较碱烧伤组生长缓慢,PMN计数及VEGF表达较碱烧伤组均明显减少。结论医用几丁糖可抑制碱烧伤后角膜新生血管的形成。     

人羊膜作为载体体外培养兔角膜上皮细胞移植治疗碱烧伤动物的实验研究

目的观察培养生长于人羊膜的兔角膜上皮细胞使其扩增并移植治疗角膜碱烧伤的效果。为培养角膜上皮细胞移植技术及应用于临床实践提供最佳的理论和实验依据。方法新西兰白兔30只（30眼）,随机分为3组（n=10）,右眼制成碱烧伤模型。A组：角膜上皮细胞羊膜移植组;B组单纯羊膜移植组;C组为对照组（碱烧伤后不作任何移植）。术后观察角膜透明度、角膜新生血管及上皮修复情况,裂隙灯显微镜照相记录。3组均于术后1周、2周、1个月及3个月时各取1眼角膜标本行病理组织检查。结果A组除1眼移植片在第7天脱落外,所有移植片在术后3d水肿消退,角膜逐渐透明。B组移植片持续水肿,眼前段炎性反应稍重,但较碱烧伤对照组轻。C组角结膜高度水肿浑浊,烧伤后观察3个月未发现角膜恢复透明现象。病理组织检查显示：A组角膜及周边上皮细胞为多层结构,角膜新生血管消失,基质的炎性细胞浸润减退;B组覆盖上皮细胞表现为完整上皮细胞型,C组角膜浑浊,新生血管及肉芽组织形成。结论人羊膜作载体体外培养兔角膜上皮细胞移植重建角膜基底膜和角膜上皮结构治疗兔碱烧伤后的角结膜损伤是一种合理有效的方法。     

Avastin不同给药途径对兔角膜新生血管及超微结构的影响

目的研究阿瓦斯汀不同给药途径对兔角膜新生血管及超微结构的影响。方法健康新西兰大白兔50只,随机选取48只兔左眼制作碱烧伤角膜新生血管动物模型,造模成功后随机分为局部滴眼组(A组)、结膜下注射组(B组)、角膜基质注射组(C组)和模型对照组(D组),每组12只,未造模2只兔双眼为空白对照,于碱烧伤后第1天、第4天、第11天、第18天、第32天观察兔眼结膜充血、角膜混浊、新生血管生长情况,并进行眼前节照相,同时计算各实验兔眼角膜新生血管面积;第11天、第18天、第32天每组各处死4只兔,即刻抽取左眼房水检测血管内皮生长因子(vascular endothelial growth factor,VEGF)含量,取新生血管生长最旺盛的角膜组织分别固定,待做电镜、免疫组织化学等检测。结果角膜新生血管在碱烧伤后11d内生长迅速,第18天时有所消退,第32天时趋于相对稳定,A组、B组、C组角膜新生血管面积与D组在各个时间点之间比较,差异均有统计学意义(均为P<0.05)。碱烧伤后各时间点房水中VEGF浓度均高于正常水平,碱烧伤后11d内房水中VEGF浓度逐渐升高,至第18天时达到高峰,第32天时有所下降并趋于较稳定的水平。CD31在正常兔眼角膜组织中未见表达,A组、B组、C组阳性细胞数明显少于D组,差异均有统计学意义(均为P<0.05)。A组、B组、D组角膜超微结构在第11天、第18天、第32天时除碱烧伤损伤外无明显其他改变,在第18天、第32天时C组角膜超微结构损伤重于A组、B组、D组。结论局部滴眼、结膜下注射、角膜基质注射三种给药途径均对角膜新生血管有较好的抑制作用。局部滴眼与结膜下注射给药途径简单安全、效果稳定,未见对角膜超微结构产生明显影响;角膜基质注射虽短期效果显著,但对角膜超微结构产生了较明显的影响。     

兔眼脉络膜黑色素瘤的第二代光敏剂光动力治疗

目的 观察第二代光敏剂CASPc（chloroaluminum su lfonated phthalocyanine,CASPc）对B16F10黑色素瘤动物模型的光动力治疗（PDT）作用 。 方法 38只新英格兰大白兔经免疫抑制后种植B16F10黑色素瘤碎片于脉络膜下腔，B型超声、间接检眼镜随访肿瘤生长至2.0 ~3.8 mm厚时30只兔眼给予PDT治疗。耳静脉注射CASPc 5 mg/kg, 24 h后给予氩-染料激光照射，激光波长675 nm, 输出功率600 nm/cm2，激光照射剂量20~70 J/cm2；8只对照组兔眼只给予激光或光敏物质。治疗后观察6~8周。 结果 38只兔眼建模成功。30只PDT治疗兔眼中21只眼肿瘤得到控制，9只眼未能控制；对照组兔眼肿瘤治疗后2周充满整个玻璃体。 结论 第二代光敏剂CASPc对实验性眼B16F10黑色素瘤具有一定的PDT治疗作用。 （中华眼底病杂志，2004，20：67-132）     

羊膜移植和高压氧抑制碱烧伤角膜VEGF表达的比较研究

目的 探讨羊膜移植或高压氧治疗对碱烧伤角膜内血管内皮生长因子(vascular endothelial growth factor，VEGF)及角膜新生血管形成的抑制作用。方法 21只兔(42只眼)被建立角膜碱烧伤动物模型后随机分为羊膜移植组、高压氧治疗组和对照组，每组7只兔(14只眼)。羊膜移植组、高压氧治疗组分别行羊膜移植和高压氧治疗。采用免疫组化染色检查VEGF蛋白的表达，宏观测量新生血管长度及生长速度，显微镜下微血管计数方法研究角膜新生血管形成及抑制情况。结果 羊膜移植组和高压氧治疗组VEGF蛋白表达下降，新生血管生长速度变慢，微血管数量减少，3组比较具有统计学意义。VEGF主要表达在角膜受损区的感染细胞胞浆内，其出现时间和位置与角膜新生血管一致。结论 VEGF是一种重要的角膜内新生血管形成因子，其变化与角膜新生血管平行；羊膜移植或高压氧治疗可抑制碱烧伤角膜VEGF的表达及角膜新生血管的形成。     

PDT治疗65例脉络膜新生血管临床分析

目的:研究光动力疗法(photodynamic therapy,PDT)治疗脉络膜新生血管的效果和相关护理的价值。方法:回顾性分析我科用PDT治疗65例68眼脉络膜新生血管的效果、并发症及处理效果。结果:31眼(46%)视力提高2行及以上,33眼(49%)视力变化在2行以内,4眼(6%)视力下降2行以上;41眼荧光素渗漏停止(60%),22眼荧光素渗漏减少(32%),而5眼荧光素渗漏增加(8%);2例输液相关性背痛,未发生药液渗漏和皮肤光敏反应。全部治疗病例对治疗结果无不满意。结论:PDT治疗脉络膜新生血管疗效可靠,详细解释和精心护理是避免医疗纠纷的关键。     

Treatment parameters for selective occlusion of experimental corneal neovascularization by photodynamic therapy using a water soluble photosensitizer, ATX-S10(Na)

Time dependent change of an accumulation of an amphiphilic photosensitizer, ATX-S10(Na) on rabbit corneal neovascularization (CoNV) was evaluated by angiography using ATX-S10(Na) as a fluorescent dye on three rabbits. The angiography showed that the dye accumulated on CoNV 3-5 hr after dye injection when the dye in the iris was minimum. The results suggested 3-5 hr after might be the optimal time to start photodynamic therapy (PDT) to occlude CoNV selectively without damage to the surrounding normal tissue such as the iris. Then the optimal treatment parameters in PDT using ATX-S10(Na) for selective occlusion of the CoNV were investigated on rabbit eyes. PDT was performed with two different time intervals between dye injection and laser irradiation of a diode laser (670 nm), different laser doses and three different dye doses on 21 animals. PDT performed immediately after dye injection selectively occluded CoNV with laser irradiations from 30.6 to 38.2 J cm(-2)and a 2 mg kg(-1)dose of ATX-S10(Na), as well as with 15.3 J cm(-2)and a 6 mg kg(-1)dose. PDT performed 4 hr after dye injection with 107.0-152.8 J cm(-2)and a 6 mg kg(-1)dose, as well as with 38.2-53.5 J cm(-2)and a 12 mg kg(-1)dose was also effective. Although PDT performed either immediately or 4 hr after ATX-S10(Na) injection selectively occluded CoNV, the width of the optimal range of radiant exposures seemed wider in PDT performed 4 hr after dye injection. It is supposed that this result is associated with the difference of dye accumulation between in CoNV and in normal tissue as shown by the present angiographical findings.     

Effect of photodynamic therapy with ATX-S 10 (Na) on experimental choroidal neovascularization

PURPOSE: To evaluate an appropriate irradiative condition for selective occlusion of experimental choroidal neovascularization(CNV) with photodynamic therapy (PDT) using ATX-S 10 (Na). METHODS: Experimental CNV was induced in monkey eyes by laser photocoagulation. PDT(dose of irradiative energy 40 to 80J/cm2) was performed after 3.5 mg/kg of body weight intravenous injections of ATX-S 10(Na). CNV and retinal vessel occlusion induced by PDT was evaluated by fluorescein angiography (FA) at 1 and 7 days after irradiation. If FA showed no fluorescein dye leakage from CNV at 1 and 7 days after irradiation, CNV was evaluated by histopathological analysis at 7 days after irradiation. RESULTS: Within 30 to 33 minutes after ATX-S 10(Na) injection and irradiation with 50 to 60 J/ cm2, FA showed no fluorescein dye leakage from CNV and no closure of retinal vessels at 1 and 7 days after irradiation. Light micrographs showed occluded CNV, and retinal vessels remained patent and there was no apparent change in the inner layer of the retina. CONCLUSIONS: Irradiative condition of ATX-S10 (Na) 3.5 mg/kg was appropriate 30 to 33 minutes after ATX-S 10(Na) injection and irradiation with 50 to 60 J/cm2.     

Photodynamic therapy for corneal neovascularization using topically administered ATX-S10 (Na)

BACKGROUND AND OBJECTIVE: We investigated the effect of photodynamic therapy (PDT) using topically administered ATX-S10(Na) on corneal neovascularization (CoNV). MATERIAL AND METHODS: Rabbit eyes with induced CoNV were treated with ATX-S10(Na) eye drops (10 mg/mL) every 5 minutes, 5 to 25 times. Five to ninety minutes after topical administration, the CoNV were irradiated with a diode laser using a wavelength of 670 nm. RESULTS: The CoNV were occluded fluorescein angiographically in 7 of 16 treated eyes. The eyes having occluded, CoNV were irradiated using fluence of 510-1019 J/cm2 within 20 minutes of eye-drop administration. However, the effect was more variable than what we found using systemic administration in our previous investigation. CONCLUSIONS: Experimental CoNV was occluded by photodynamic therapy using topically administered ATX-S100(Na), suggesting this modality as a possible treatment for CoNV avoids the side effects found with systemic administration of the dye. Further efforts to improve the eye drops in terms of pH and osmotic pressure are needed to achieve increased dye accumulation.     

Application of femtosecond ultrashort pulse laser to photodynamic therapy mediated by indocyanine green

BACKGROUND/AIMS: To evaluate treatment with high peak power pulse energy by femtosecond ultrashort pulse laser (titanium sapphire laser) delivered at an 800 nm wavelength for corneal neovascularisation using photodynamic therapy (PDT) mediated by indocyanine green (ICG). METHODS: Using a gelatin solid as an in vitro corneal model, the safety of laser power was studied to determine if it degenerated gelatin with or without ICG. The authors then induced corneal neovascularisation in rabbit eyes by an intracorneal suturing technique. Fluorescein angiography was used to evaluate occlusion before PDT and 0, 1, 3, and 10 days after PDT. The authors performed light microscopy with haematoxylin eosin staining and transmission electron microscopy to determine thrombosis formation in the neovascular regions. RESULTS: The threshold of peak laser power density ranged from 39 to 53 W/cm(2). Laser irradiation was started 30 seconds after a 10 mg/kg ICG injection, and all irradiated segments were occluded at 0, 1, 3, and 10 days at 3.8 J/cm(2). Light and electron microscopy documented thrombosis formation in the neovascular region. CONCLUSION: Femtosecond pulse laser enhanced by ICG can be used for PDT. Because of effective closure of corneal neovascularisation at a low energy level, the high peak power pulse energy of the femtosecond pulse laser might be more efficacious than continuous wave laser for use with PDT.     

Induction of conjunctival transdifferentiation on vascularized corneas by photothrombotic occlusion of corneal neovascularization

Previous studies have established that conjunctival transdifferentiation (transformation into cornea-like morphology) is inhibited by corneal vascularization. Conversely, occlusion of corneal vessels may induce conjunctival transdifferentiation on vascularized corneas. To test this hypothesis, the corneal epithelia of New Zealand albino rabbits were debrided 3 mm beyond the limbus with n-heptanol. Sixteen corneas healed by conjunctival epithelium, with vascularization persisting for 20 months, were used in this study. Photochemically induced occlusion of the corneal vessels was achieved by intravenous administration of rose bengal-saline solution (40 mg/kg body weight) with subsequent argon laser irradiation of the vessels (514.5 nm, 130 mW, 63 micron and 0.2 sec). The treated vessels remained occluded in an 18-week study, as confirmed by corneal fluorescein angiography. Corneal clarity and epithelial integrity were improved after treatment. Goblet cell loss and morphologic transformation into a cornea-like epithelium were verified by flat-mount preparations, histology, impression cytology, and immunofluorescence studies using a mucin-specific monoclonal antibody. These results indicate that conjunctival transdifferentiation can be induced on vascularized corneas after occlusion of corneal vessels by photothrombosis.     

PDT to monkey CNV with ATX-S10(Na): inappropriateness of early laser irradiation for selective occlusion

PURPOSE: There is controversy about which mode of laser irradiation, early irradiation with low-dose photosensitizer or late irradiation with high-dose, benefits the selective occlusion of choroidal neovascularization (CNV) in photodynamic therapy (PDT). In this study, using an amphiphilic photosensitizer, 13,17-bis (1-carboxypropionyl) carbamoylethyl-8-etheny-2-hydroxy-3-hydroxyiminoethylidene-2,7,12,18-tetraethyl porphyrin sodium (ATX-S10(Na); Photochemical Inc., Okayama, Japan), photodynamic and adverse effects of early irradiation on CNV-bearing monkey eyes were investigated. METHODS: Experimentally induced CNV lesions and normal retina were irradiated with a diode laser (670-nm wavelength) at a dose of 1 to 90 J/cm(2) at 1 to 19 minutes after intravenous injection of 2 mg/kg body weight of ATX-S10(Na). Vascular occlusion and CNV recurrence were evaluated by fluorescein and indocyanine green angiography and histologic analysis, until 4 weeks after irradiation. RESULTS: Of 45 different conditions, 23 did not induce CNV closure, 20 provided both CNV occlusion and retinal vessel damage, and 2 achieved selective CNV occlusion without retinal vascular injury. Recurrence of CNV was induced in 19 of 22 CNV-occluding conditions. ATX-S10(Na) angiography showed that dyes were similarly distributed between normal vessels and CNV at early time periods after injection, whereas they were preferentially accumulated in CNV after 30 minutes. CONCLUSIONS: In PDT with ATX-S10(Na), irradiation within 20 minutes of dye injection failed to induce selective CNV occlusion, probably because there is no significant difference in the biodistribution of dye between CNV and retinal vessels. It also caused frequent CNV recurrence after extensive inflammation in the irradiated retina.     

Evaluation of the new photosensitizer Stakel (WST-11) for photodynamic choroidal vessel occlusion in rabbit and rat eyes

PURPOSE: To evaluate the photodynamic potential of a new hydrosoluble photosensitizer (WST-11, Stakel; Steba Biotech, Toussus-Le-Noble, France), for use in occlusion of normal choroidal vessels in the rabbit eye and CNV (choroidal neovascularization) in the rat eye. METHODS: Occlusive and nonocclusive parameters of Stakel and verteporfin photodynamic therapy (PDT) were investigated in pigmented rabbits. Eyes were followed by fluorescein angiography (FA) and histology at various intervals after PDT. RESULTS: When occlusive parameters (fluence of 50 J/cm(2), 5 mg/kg drug dose and DLI [distance to light illumination] of 1 minute) were used, Stakel PDT was efficient immediately after treatment without associated structural damage of the RPE and retina overlying the treated choroid in the rabbit eye. Two days later, total occlusion of the choriocapillaries was seen in 100% of the treated eyes, along with accompanying histologic structural changes in the overlying retina. When the occlusive parameters (fluence, 100 J/cm2; drug dose, 12 mg/m2; and DLI, 5 minutes) of verteporfin PDT were used, occlusion of the choriocapillaries was observed in 89% of the treated eyes. Histology performed immediately after treatment demonstrated structural damage of the overlying retina and RPE layer. Weaker, nonocclusive Stakel PDT parameters (25 J/cm2, 5 mg/kg, and DLI of 10 minutes) did not induce choriocapillary occlusion or retinal lesions on FA or histology. Weaker, nonocclusive verteporfin PDT parameters (10 J/cm2, 0.2 mg/kg, and DLI of 5 minutes) did not induce choriocapillary occlusion. However, histology of these eyes showed the presence of damage in the retinal and choroidal tissues. Moreover, preliminary results indicate that selective CNV occlusion can be achieved with Stakel PDT in the rat eye. CONCLUSIONS: Unlike verteporfin PDT, Stakel PDT does not cause direct damage to the RPE cell layer or retina. These observations indicate that Stakel PDT may have a high potential for beneficial therapeutic outcomes in treatment of AMD.     

Dose-related structural effects of photodynamic therapy on choroidal and retinal structures of human eyes

PURPOSE: To determine the effects of photodynamic therapy (PDT) on choroidal and retinal structures of human eyes. METHODS: One eye from each of three patients with large malignant melanomas of the uvea destined for enucleation received PDT using verteporfin according to the approved treatment recommendations for patients with age-related macular degeneration. Two laser spots and two light doses (50 J/cm(2) and 100 J/cm(2)) were applied in unaffected chorioretinal areas. The effects of PDT were assessed by fluorescein and indocyanine-green angiography. The eyes were enucleated 1 week later, fixed in buffered paraformaldehyde/glutaraldehyde solution, bisected along the laser spots, and processed for light and electron microscopy. RESULTS: In agreement with the clinical angiographic findings of hypofluorescence, a rather selective occlusion of the choriocapillary layer was observed in the 50-J/cm(2) PDT areas, whereas the 100-J/cm(2) PDT areas additionally revealed closure of deeper choroidal vessels and focal alterations of the retinal pigment epithelium. The overlying neurosensory retina, including photoreceptors and retinal capillaries, was well preserved in all PDT areas. Electron microscopy showed that alterations of the choriocapillary endothelium comprised swelling, shrinkage and fragmentation of endothelial cells, detachment from their basement membrane up to complete degeneration of the endothelial lining, leading to platelet aggregation, degranulation, and thrombus formation. Complete occlusion of capillary lumina by fibrin, thrombocytes, and cellular debris was observed. Remaining intact endothelial cells appeared to be reorganized into novel smaller vascular channels within occluded lumina. CONCLUSIONS: PDT with verteporfin at a dosage used clinically induces selective occlusion of the physiological choriocapillaris without affecting deeper choroidal, retinal, and optic nerve vessels or the overlying retinal pigment epithelium and neurosensory retina. The main mechanism of action appears to be vascular thrombosis induced by cytotoxic damage of endothelial cells and platelet activation. An increase in light dose enhances the occlusive effect with thrombosis within deeper choroidal layers and damage to the retinal pigment epithelium. However, photoreceptors remained intact at all light doses used.     

Choroidal vein and artery occlusion following photodynamic therapy in eyes with pathologic myopia

Purpose To describe highly myopic patients in which either the large choroidal veins or arteries were occluded following PDT treatment.Methods Demographic features of two highly myopic patients in which large choroidal vessels were occluded at 1 week following PDT, among a total of 23 patients who received PDT due to choroidal neovascularization (CNV) caused by high myopia, were demonstrated.Results In case 1, ICG angiography demonstrated the complete occlusion of several large choroidal veins within the laser-applied area at 1 week after PDT. In case 2, ICG angiography demonstrated an occlusion of choroidal artery emanating from beneath the CNV. One month after PDT, re-perfusion of the occluded choroidal vessels was noted in both patients.Conclusion Occlusion of choroidal veins has never been reported in eyes with CNV treated by verteporfin therapy. Although further studies are necessary, occlusion of large choroidal vessels might happen in highly myopic eyes more commonly than expected. ICG angiography at 1 week after PDT was useful to evaluate the impact of PDT on large choroidal vessels.This study was in part supported by 17591823 and 16390495 from Japan Society for Promotion of Science.