Pulsatile ocular blood flow in asymmetric exudative age related macular degeneration

BACKGROUND/AIMS: Decreased perfusion or increased vascular resistance of the choroidal vessels had been proposed as the vascular pathogenesis for age related macular degeneration (AMD). This study planned to answer the question whether pulsatile ocular blood flow (POBF) was different in patients with asymmetric exudative AMD between eyes with drusen, choroidal neovascularisation (CNV), or disciform scar. METHODS: 37 patients with asymmetric exudative AMD were enrolled in this observational case series study. POBF were measured in both eyes of each subject. Eyes with high myopia, anisometropia, recent laser treatment, and glaucoma were excluded. RESULTS: After adjusting for ocular perfusion pressure, intraocular pressure, and pulse rate, multivariate regression analysis with generalised estimating equation showed POBF was significantly higher in eyes with CNV (1217 (SD 476) microl/min) than the contralateral eyes with drusen (1028 (385) microl/min) (p = 0.024). Eyes with disciform scar had lower POBF than the contralateral eyes with drusen (999 (262) microl/min and 1278 (341) microl/min, respectively, p<0.001). There was no significant correlation between the POBF and the lesion size of the CNV. CONCLUSION: The POBF in eyes with drusen was lower than their fellow eyes with CNV, but higher than their fellow eyes with disciform scar. This finding suggests that haemodynamic differences between fellow eyes in individuals are relevant to the development of CNV and the formation of disciform scar. Further studies on the follow up patients might shed light on the pathogenesis of exudative AMD.     

Pulsatile ocular blood flow in asymmetric age-related macular degeneration

PURPOSE: Ocular perfusion abnormalities have been proposed in the pathogenesis of age-related macular degeneration (AMD) with differences in pulsatile ocular blood flow (POBF) in eyes with asymmetric AMD in Japanese and Taiwanese patients. The purpose of our study was to observe POBF difference in the fellow eyes of Caucasians with asymmetric AMD. METHODS: This was a cross-sectional study comparing POBF in three groups of patients with asymmetric AMD in the fellow eyes: Group 1 (n=21) with drusen and active choroidal neovascularisation (CNV); Group 2 (n=18) with drusen and disciform scar; Group 3 (n=8) with CNV and disciform scar. The POBF was adjusted for intraocular pressure (IOP), pulse rate (PR), and axial length using multiple regression analysis. Generalised estimation equation model was used to include both eyes in each group. RESULTS: The geometric mean (95% confidence interval) POBF values were as follows: Group 1 with drusen 1097.9 microl/min (957.0, 1259.7) in one eye and the fellow eye with CNV 1090.1 microl/min (932.3, 1274.7); Group 2 with drusen 946.0 microl/min (794.2, 1126.7) and disciform scar 966.2 microll/min (780.3, 1196.4); Group 3 with CNV 877.1 microl/min (628.3, 1224.6) and disciform scar 767.2 microl/min (530.5, 1109.7). Adjusting for differences in axial length, pulse rate and intraocular pressure, no statistically significant difference in POBF was found between fellow eyes in the same subject. CONCLUSIONS: POBF is not different between fellow eyes of Caucasian patients with asymmetric AMD.     

Reduced foveolar choroidal blood flow in eyes with increasing AMD severity

PURPOSE: In an earlier study, the authors reported that foveolar choroidal blood flow (ChBFlow) decreases in patients with AMD and drusen. To explore further the choroidal circulatory changes in patients with AMD, the relationship between ChBFlow and fundus features associated with increased risk of choroidal neovascularization (CNV) were investigated. METHODS: The study included 26 control eyes of 17 normal subjects and 163 eyes with early AMD characteristics of 123 patients with AMD. The AMD study eyes were divided into three groups according to increasing risk for development of CNV: (1) drusen > or =63 microm, no RPE hyperpigmentary changes in the study eye, and no CNV in the fellow eye; (2) drusen > or =63 microm, RPE hyperpigmentary changes in the study eye, and no CNV in the fellow eye; and (3) eyes with CNV in the fellow eye. Laser Doppler flowmetry was used to assess relative foveolar choroidal blood velocity (ChBVel), volume (ChBVol), and flow (ChBFlow). Differences in the mean circulatory parameters were assessed by analysis of variance (ANOVA) and test of linear trend. RESULTS: Mean ChBVel, ChBVol, and ChBFlow decreased with increased risk for CNV (linear trend, P < 0.05). The lowest circulatory parameters were observed in the eyes with the highest risk for CNV development. Trends for ChBVel and ChBFlow were still significant after adjustment for multiple factors. CONCLUSIONS: There is a systematic decrease in choroidal circulatory parameters with an increase in the severity of AMD features associated with risk for the development of CNV, suggesting a role for ischemia in the development of CNV.     

Pulsatile ocular blood flow study: decreases in exudative age related macular degeneration

BACKGROUND: Pulsatile ocular blood flow (POBF) is a parameter for evaluating choroidal blood flow. POBF in the patients with non-exudative and exudative age related macular degeneration (AMD) was investigated. METHODS: POBF, pulse amplitude (PA), systolic and diastolic blood pressures, intraocular pressure (IOP), refractive error, and axial length were compared among 10 patients with non-exudative AMD, 11 patients with exudative AMD, and 69 age matched controls. A Langham OBF computerised tonometer was used with the participants in the sitting position to measure POBF and PA. RESULTS: No significant differences were found in age, systolic and diastolic blood pressures, IOP, or refractive error between patients with exudative and non-exudative AMD and the control subjects. In the patients with exudative AMD the POBF (median, 372.7 microl/min) and PA (median, 1.2 mm Hg) were significantly lower than in the patients with non-exudative AMD (median, 607.0 microl/min (p = 0.02) and 2.2 mm Hg (p = 0.04), respectively) and control subjects (median, 547.4 microl/min (p = 0.01) and 2.0 mm Hg (p = 0.01), respectively). CONCLUSIONS: These data show that the POBF and PA in the patients with exudative AMD are lower than in the patients with non-exudative AMD and normal subjects. Decreased choroidal blood flow may have a role in the development of choroidal neovascularisation in AMD.     

Transpupillary thermotherapy for the treatment of subfoveal choroidal neovascularization associated with age-related macular degeneration

OBJECTIVE: To evaluate the efficacy of transpupillary thermotherapy (TTT) for the treatment of choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). DESIGN: Prospective, non-randomized, non-masked, case-selected series. METHODS: All patients with subfoveal CNV due to AMD and initial visual acuity (VA) between 6/9 and 6/60 were offered the opportunity to undergo TTT. Recruited subjects were treated using a diode laser (810 nm) with a beam size of 1.2-3.0 mm and power settings of 460-1200 mW. Treatment was applied for 60 seconds in a subthreshold manner. MAIN OUTCOME MEASURES: Differences in VA and changes in the angiographic appearance of CNV. RESULTS: Thirty-one occult/predominantly occult and five classic/predominantly classic membranes were treated with TTT and were followed-up for a mean of 6.0 +/- 1.2 months. Following an average of 1.5 +/- 0.7 (range 1-4) laser sessions, VA remained stable ( -1 to +1 Snellen line) in 24 (66.7%) eyes, improved by > 1 line in two (5.6%) eyes and decreased significantly (> or = 2 Snellen lines) in 10 (27.8%) eyes. Angiographically confirmed closure of CNV was detected in 22 (61.1%) patients. Membranes persisted in 11 (30.6%) eyes and recurred in three (8.3%) eyes. There was no association between reduction, elimination or persistence of angiographic leakage of CNV and change in VA after treatment (p = 0.347). CONCLUSIONS: Transpupillary thermotherapy may be effective at preserving vision and reducing CNV leakage in a number of patients with exudative AMD. Further studies are required to compare TTT with the natural course of subfoveal CNV and alternative treatment options.     

Pigment epithelium-derived factor is deficient in the vitreous of patients with choroidal neovascularization due to age-related macular degeneration

PURPOSE: Pigment epithelium-derived growth factor (PEDF) is a potent inhibitor of angiogenesis that is found in the normal eye. The purpose of this study is to report decreased levels of PEDF in the vitreous of eyes with choroidal neovascularization (CNV) due to age-related macular degeneration (AMD). DESIGN: Prospective case-control study. METHODS: In a prospective case-control study, undiluted vitreous was collected from nine eyes of nine patients with CNV due to AMD and from an age-matched control group of 12 eyes of 12 patients with retinal disorders not involving neovascularization. Vitreous PEDF and vascular endothelial growth factor (VEGF) concentrations were determined by Western blot analyses and enzyme-linked immunosorbent assay (ELISA), respectively. Angiogenic activities of the vitreous samples were assessed in vitro using an endothelial cell chemotaxis assay. RESULTS: In vitreous samples from nine eyes with CNV due to AMD the mean +/- SD PEDF level was 2.8 ng/microl +/- 1.3 ng/microl. In vitreous samples from 12 age-matched control eyes the mean +/- SD PEDF level was 16.4 ng/microl +/- 7.1 ng/microl. The difference between the two groups was statistically significant (P =.00003). No significant difference in vitreous VEGF concentration was seen between CNV/AMD samples and control samples (P =.23). All CNV/AMD vitreous samples induced endothelial cell migration in vitro. No sample from age-matched non-age-related macular degeneration controls could induce endothelial cell migration, and 11 of 12 were able to block VEGF-induced migration in vitro. This inhibitory activity required active PEDF. CONCLUSION: The vitreous of patients with CNV due to AMD contained lower levels of PEDF and lacked the antiangiogenic activity of vitreous from age-matched controls. This suggests that loss of PEDF creates a permissive environment for CNV patients with AMD.     

Transpupillary thermotherapy for the treatment of choroidal neovascularization in age-related macular degeneration in Taiwan

PURPOSE: To evaluate the therapeutic outcome and the recurrence of choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) after transpupillary thermotherapy (TTT) in light-brown retinas. METHODS: A retrospective, non-randomized study of 58 eyes in 55 patients with subfoveal CNV treated with TTT was conducted. Power settings were set about half the value for Caucasian eyes. The outcome was assessed with best-corrected visual acuity, fluorescein angiography, indocyanine green angiography, and fundoscopic examination. RESULTS: Forty-four membranes were occult, six classic, and eight mixed. Mean follow-up was 16.6+/-10.7 months (range: 6-48 months). Membranes closed in 46 eyes. Iatrogenic complications included three subretinal haemorrhage, two retinal pigment epithelium tears, and two macular area cystic changes. In eyes with occult CNV, visual acuity improved in six (13.6%), 14 (31.8%) remained unchanged, and 24 (54.6%) deteriorated. For various CNV, average logMAR changes from baseline at last follow-up were 0.30 in occult, -0.08 in classic, and 0.59 in mixed (P<0.01). Thirty eyes experienced recurrence within 9.2+/-6.2 months (range: 2-22 months). Cumulative recurrence rate was 45% at 12 months and 71% at 22 months, with no significant difference between occult and non-occult type CNV. CONCLUSIONS: Transpupillary thermotherapy does not cure CNV secondary to AMD. High recurrence was found independent of CNV type. Most improved vision was found mostly in classic CNV. Complications associated with high energy level should be considered in light-brown retinas.     

经瞳孔温热疗法治疗老年性黄斑变性的疗效观察

目的 观察经瞳孔温热疗法(transpupillary thermotherapy,TTT)治疗渗出型老年性黄斑变性(age—related macular degeneration，AMD)隐匿型脉络膜新生血管(choroidal neovascularization，CNV)的效果。方法 对28例34眼经眼底荧光血管造影(fundus fluorescein angiography，FFA)及吲哚青绿血管造影(indocyanine green angiography，ICGA)确诊的继发于渗出型AMD的隐匿型CNV行TTT治疗，并主要以视力、眼底检查、FFA及ICGA改变为指标，评价TTT治疗渗出型AMD的效果。结果 随访3～20个月，平均6.65个月，视力提高19眼，视力稳定13眼，视力下降2眼，视网膜水肿基本消退6眼，水肿明显减轻21眼，水肿无明显变化5眼，2眼水肿加重，出血吸收22眼，8眼出血减少，出血无明显变化者2例，另有2眼发生少量新鲜视网膜深层出血，第1次治疗后复查FFA及ICGA，10眼CNV消失，19眼CNV渗漏减轻，3眼无明显变化，2眼CNV增大。结论 TTT治疗可使大部分AMD患者视力稳定或提高，是一种极具潜力的治疗方式，但对其确切疗效的评价。尚需与自然病程及其他治疗方法对比。     

Long-term efficacy of transpupillary thermotherapy for subfoveal choroidal neovascularization in age-related macular degeneration

AIM: To determine the long-term efficacy of transpupillary thermotherapy (TTT) in the treatment of subfoveal choroidal neovascularization (CNV) in age-related macular degeneration (AMD). METHODS: Fourteen eyes of 14 patients with subfoveal CNV secondary to AMD were treated with diode laser (810nm) TTT. The mean age was 67.1 years. Complete ophthalmic examination was done, color fundus photographs and macular optical coherence tomography scans were taken, fluorescein and indocyanine green angiography were performed during initial and at subsequent follow-up examinations. Treatment was given in one minute using 2-3mm spot sizes, and laser power settings were between 650-800mW. The follow-up period was between 5 and 64 months and the mean was 28.6 months. RESULTS: There was subfoveal classic CNV in 10, predominantly classic CNV in 2, minimally classic CNV in 1, and type 1 occult CNV in one of the fourteen eyes. Four patients were noted to have post-treatment hemorrhage which was absorbed in a short time. Macular non-perfusion occurred in one patient immediately after treatment. Most of the eyes demonstrated a decrease in exudation during the follow-up. With a mean follow-up of 28.6 months, visual acuity improved in 5, remained the same in 8 and decreased in 1 of the 14 eyes. CONCLUSION: Transpupillary thermotherapy is shown to close subfoveal CNV with rapid resolution of subretinal fluid while maintaining visual function in patients with AMD. It may be performed as an alternative laser treatment in classic and predominantly classic subfoveal choroidal neovascularization due to AMD.     

经瞳孔温热疗法和光动力疗法治疗渗出型老年性黄斑变性短期疗效比较

目的 比较经瞳孔温热疗法(TTT) 和光动力疗法(PDT)治疗渗出型 老年性黄斑变性(AMD)脉络膜新生血管(CNV)的疗效。 方法 对比分析渗出性AMD患者行PDT 治疗的35例42只眼、TTT治疗的35例40只眼治疗前和治疗后3个月的临床资料。所有患者治疗前后均进行视力 、荧光素眼底血管造影（FFA）、吲哚青绿血管造影（ICGA）和光相干断层扫描（OCT）检查 。CNV类型均为黄斑中心凹下型或旁中心凹型。其中，隐匿性或隐匿性为主型的CNV44只眼 ，典型性及典型性为主型的CNV38只眼。PDT治疗的42只眼中，隐匿性或隐匿性为主型CNV19只眼，典型性或典型性为主型CNV23眼；TTT治疗的40只眼中，隐匿性或隐匿性为主型CNV25只眼，典型性及典型性为主型CNV15只眼。 结果 典型性或典型性为主型CNV治疗后1、3个月时，PDT组分别有47.8%、43.5%的患眼视力提高2行以上；TTT组分别有6.7%、6.7%的患眼视力提高2行以上。两组之间治疗后1、3个月时视力提高的比例比较，差异均有显著性的意义（χ2=7.118,P=0.0076；χ2=5.500,P=0.0190）。PDT组分别有100%、69.6%的患眼CNV荧光素渗漏停止或改善；TTT组分别有53.2%、80.0%的患眼CNV荧光素渗漏停止或改善。两组之间治疗后1个月时CNV荧光素渗漏停止或改善的比例比较，差异有显著性的意义（χ2=13.16,P=0.0003）；3个月时CNV荧光素渗漏停止或改善的比例比较，差异无显著性的意义（χ2=0.5098,P=0.4752）。隐匿性或隐匿性为主型CNV治疗后1、3个月时，PDT组分别有15.8% 、10.5%的患眼视力提高2行以上；TTT组分别有4.0%、8.0%的患眼视力提高2行以上。两组之间治疗后1、3个月时视力提高的比例比较，差异均无显著性的意义（χ2=1.816,P=0.17 78；χ2=0.0838,P=0.7728）。PDT组分别有78。9%、42.1% 的患眼CNV荧光素渗漏停止或改善；TTT组分别有52.0%、84.0%的患眼CNV荧光素渗漏停止或改善。两组之间治疗后1个月时CNV荧光素渗漏停止或改善的比例比较，差异无显著性的意义（2=3.388,P=0.0657）；3个月时CNV荧光素渗漏停止或改善的比例比较，差异具有显著性的意义（χ2=8.433,P=0.0037）。 结论 典型性及典型性为主型CNV治疗后3个月视力结果PDT优于TTT；治疗后1个月时FFA检查渗漏改善PDT明显优于TTT，但随诊至3个月时，二者疗效差异无显著性的意义。隐匿性或隐匿性为主型CNV治疗后3个月视力结果PDT与TTT差异无显著性的意义；治疗后1个月FFA检查渗漏改善改善PDT与TTT差异无显著性的意义，但随诊至3个月时，CNV渗漏消失和减少方面TTT疗效明显好于PDT。尚需要更多的病例及更长的随诊时间来评价两种治疗方法的疗效.（中华眼底病杂志，2004，20：285-288）     

Pulsatile ocular blood flow in healthy Koreans

PURPOSE: To determine the normal reference range of pulsatile ocular blood flow (POBF) values in healthy Korean subjects and to find out the factors that may affect them. METHODS: A total of 280 eyes of 280 normal subjects were included in this study. Best corrected visual acuity (BCVA), intraocular pressure (IOP), axial length, POBF, systemic blood pressure, and pulse rate were measured. The mean, standard deviation, range, and the 5th and 95th percentiles of POBF were calculated, and the influences of various parameters to POBF were determined by multiple regression analyses. RESULTS: The mean POBF value was 766.0+/-221.6 microl/min in men and 1021.1+/-249.5 microl/min in women. The 5th and 95th percentiles for POBF values were 486.0 microl/min and 1140.0 microl/min in men and 672.0 microl/min and 1458.0 microl/min in women. The POBF values were significantly influenced by gender, mean blood pressure, pulse rate, and axial length. CONCLUSIONS: Even though the POBF values were influenced by gender, BP, and axial length, we could define the normal reference range of POBF in healthy Koreans.     

Changes in foveal thickness and macular function after transpupillary thermotherapy for age-related macular degeneration

PURPOSE: To evaluate the effect of transpupillary thermotherapy (TTT) on foveal thickness and macular function in eyes with choroidal neovascularization (CNV) associated with age-related macular degeneration. METHODS: Sixteen eyes with occult CNV and 6 eyes with classic CNV were treated with TTT. Optical coherence tomography and focal macular electroretinograms (FMERGs) elicited by a 15-degree stimulus were performed before, 3 months after TTT in 22 eyes and 6 months after TTT in 18 eyes. RESULTS: Before TTT, the fovea in 20 of the 22 eyes with CNV was significantly thicker than that of normal subjects. The foveal thickness was reduced after TTT in 11 of 14 eyes with occult CNV and remained unchanged in 2 eyes. One eye with occult CNV before TTT developed a classic CNV with significant macular edema and increased foveal thickness 3 months after TTT. The amplitudes of the FMERGs were reduced in all eyes before TTT. In eyes with occult CNV, the mean b-wave amplitude increased significantly after TTT (p = 0.0260 at 3 months, p = 0.0142 at 6 months). When the change of foveal thickness was less than 20% after TTT, all eyes with occult CNV had a 30% or more increase in the b-wave amplitude. In eyes with classic CNV, the mean amplitude of the a- and b-waves did not change significantly after TTT. CONCLUSIONS: TTT improves macular function in eyes with occult CNV associated with age-related macular degeneration more when the change of foveal thickness is slight.     

经瞳孔温热疗法治疗年龄相关性黄斑变性

年龄相关性黄斑变性（AMD）是老年人致盲的常见原因。根据其临床表现可分为干性和湿性。湿性AMD以视网膜色素上皮（RPE）下有活跃的脉络膜新生血管（CNV）为主要特征，而引起视力下降的主要原因是CNV引起的黄斑区反复出血、渗出、瘢痕改变，视力预后极差。经瞳孔温热疗法（TTT）是一种治疗继发于AMD的CNV的较新方法，采用直径可调节的大光斑，穿透深的激光连续照射，使靶组织缓慢升温，在消除CNV病灶的同时又相对保存病变表面视网膜的结构和功能。就TTT治疗AMD的应用发展、特点、临床疗效、治疗方法以及可能出现的并发症等作一综述。     

Pulsatile ocular blood flow and choroidal blood flow in age-related macular degeneration

BACKGROUND: The determination of pulsatile ocular blood flow (POBF) by measuring intraocular pressure pulse is a reliable way of evaluating choroidal blood flow. METHODS: We studied ocular haemodynamic abnormalities by examining the choroidal blood flow using POBF in patients with age-related macular degeneration (AMD). RESULTS: POBF was lower in patients with exudative AMD than in patients with non-exudative AMD and normal subjects. CONCLUSION: The decreased choroidal blood flow may induce choroidal neovascularization via angiogenic factor induced by hypoxia in patients with exudative AMD. Further studies of choroidal circulation, which may be important for the understanding the mechanism of AMD, are needed.     

黄斑脉络膜新生血管的PDT与TTT疗效对比观察

目的 比较经瞳孔温热疗法(TTT)与光动力疗法(PDT)治疗黄斑脉络膜新生血管的疗效.方法 对比分析渗出性老年黄斑变性(AMD),特发性脉络膜新生血管,病理性近视.眼底血管样条纹继发黄斑CNV97例101只眼治疗后1个月,3个月的矫正视力(BCVA),眼底荧光血管造影(FFA).治疗前均检杏BCVA、FFA、光学相干断层扫描(OCT),部分病例行吲哚青绿脉络膜血管造影(ICGA).其中PDT治疗52例54只眼,,TTT治疗45例47只眼.结果 PDT与TTT治疗后1月、3月矫正视力比较,PDT治疗组提高2行及2行以上与TTT治疗组比较差异无统计学意义(x2=0.27,P＞0.05,x2=0.034,P＞0.05).PDT治疗后1、3月视力提高或不变(稳定)分别有25只眼(46.2%),20只眼(37%),TTT几治疗后1、3月视力提高或不变分别有14只眼(29.8%),16只眼(34%),治疗后1月两组比较差异有统计学意义(x2=3.96,P＜0.05),治疗后3月两组比较差异无统计学意义(x2=1.78,P＞0.05).典型性或典型性为主性CNV PDT与TTT治疗后矫正视力比较,治疗后1、3月PD个组分别有40%,54%,54%,TTT治疗组分别有12.5%,12.5%PD个组视力提高2行或2行以上.两组比较差异有统计学意义(x2=7.57,P＜0.01,x2=4.14,P＜0.05).隐匿性CNVPDT与TTT治疗后矫正视力比较,治疗后1、3个月,PDT与TTT组视力无提高.治疗后1月PDT治疗组视力不变2只眼,TTT组5只眼,两组比较差异无统计学意义(x2=1.67,P＞0.05).治疗后3月两组视力均下降.PDT与TTT治疗后1、3月CNV渗漏比较,治疗后1月PDT治疗组控制或减轻CNV的荧光渗漏要好于TTT治疗组,两组比较差异有统计学意义(x2=6.64,P＜0.05.治疗后3月比较差异无统计学意义(x2=1.2,P＞0.05).结论 PDT对典型性或典型性为主CNV的治疗,随访短期内(1～3个月)在视力、及CNV渗漏方面明显优于TTT治疗.无论PDT或TTT的单一治疗对隐匿性CNV的视力提高作用不大,对于典犁性CNV或隐匿性CNV可以进行PDT与TTT的交叉治疗,但其疗效仍有待长期随访,并进行多样本及设立对照组观察比较.     

经瞳孔温热疗法治疗老年黄斑变性合并脉络膜新生血管

目的观察经瞳孔温热疗法（TTT）治疗老年性黄斑变性（AMD）合并脉络膜新生血管（CNV）的疗效。方法应用810nin半导体激光，对52例（58只眼）经荧光素眼底血管造影（FFA）和吲哚青绿脉络膜血管造影（ICGA）确诊的AMD合并黄斑区CNV患者进行TIT治疗。激光功率130～160mW／mm光斑直径。根据视力、视网膜出血和CNV渗漏变化作为疗效评定标准，随访3～18个月。结果末次随访矫正视力提高1〉2行者19只眼（32．7％），不变30只眼（51．7％），下降〉12行者9只眼（15．5％）；其中视力〉0．3者8只眼（13．7％），0．1～0．3者15只眼（25．8％），〈0．1者35只眼（60．3％）。所有患者治疗过程中无不适反应，有3例（3只眼）病灶处视网膜可见轻微发灰，中心视力下降2～3行，2个月后完全恢复。1周时2例（2只眼）出血增加，2～3个月时2例（2只眼）出现视网膜色素上皮撕裂。末诊时9只眼（17．3％）机化瘢痕形成或增厚；22只眼视网膜出血中完全吸收18只眼（81．8％）；6只眼（10．3％）出现新出血。FFA和ICGA复查，CNV闭合荧光渗漏消失或减轻40只眼（76．9％）；加重5只眼（9．6％）；新出现3只眼（5．8％）。结论TIT是治疗AMD合并CNV的一种安全、有效、价格相对便宜的方法，早期诊断、治疗CNV对提高和保存有用视力意义重大，目前更适合国内应用。     

Autofluorescence characteristics of early, atrophic, and high-risk fellow eyes in age-related macular degeneration

PURPOSE: To assess the relationships of drusen, pigment, and focally increased autofluorescence (FIAF) and the reticular pattern of hypoautofluorescence, to distinguish the combined photographic and AF characteristics of early, atrophic, and high-risk fellow eyes in AMD. METHODS: In a retrospective interinstitutional clinical study, AF and color photograph pairs of 221 eyes were examined: 166 eyes of 83 patients with bilateral large, soft drusen, with and without geographic atrophy (GA), and 55 fellow eyes of 55 patients with unilateral choroidal neovascularization (CNV). Forty-two eyes (one eye from each of 42 patients with early or atrophic AMD) were divided into four groups: 14 with drusen only, 9 with drusen and pigment abnormalities, 11 fellow eyes of patients with unilateral GA, and 8 eyes of patients with bilateral GA (acronyms for the groups: D-D, D-Pig, D-GA and GA-GA, respectively). The 55 fellow eyes of patients with CNV were divided into three groups: 19 eyes with no FIAF (CNV-0), 16 with FIAF without reticular AF (CNV-1), and 20 eyes with reticular AF and/or pseudodrusen (CNV-R). Image pairs of eyes with FIAF were registered, and drusen, pigment, and FIAF were segmented using automated background leveling and thresholding. All 221 eyes were surveyed for reticular AF and reticular pseudodrusen. The main outcome measures were (1) the fraction and relative probability of FIAF colocalizing with drusen and pigment and (2) the presence or absence of reticular AF and reticular pseudodrusen. RESULTS: The mean fractions of FIAF that colocalized with large drusen were: D-D group, 0.46 +/- 0.21; D-Pig group, 0.42 +/- 0.29; D-GA group, 0.13 +/- 0.09; and GA-GA group, 0.11 +/- 0.12. Comparisons between groups showed significant differences when comparing either the D-D group or the D-Pig group with either the D-GA group or the GA-GA group (P between 0.0001 and 0.015), whereas other comparisons were nonsignificant (Mann-Whitney rank sum test). The mean probabilities of FIAF colocalizing with large drusen relative to chance (1.0) were: D-D group, 4.7 +/- 2.5; D-Pig group, 4.3 +/- 2.3; D-GA group, 1.4 +/- 0.8; and GA-GA group, 1.8 +/- 1.3, with similar significant differences as for the colocalization fractions. The mean probability of FIAF colocalizing with small to intermediate drusen in the D-D group was 1.5 +/- 1.3, which was not significantly different from chance. In the D-Pig group, the median probability of FIAF colocalizing with pigment abnormalities was 10.0 (range, 1.1-51.0). The AF patterns in 15 of 19 eyes in the CNV-0 group were normal; the remainder had nonreticular hypoautofluorescence only. In the CNV-1 group, the relations of FIAF with drusen and pigment were similar to those in the early AMD groups. CNV-R comprised 20 of 55 eyes in the CNV group, but reticular autofluorescence and/or pseudodrusen were found in only 14 of 166 eyes of the early and atrophic groups. Of the 34 total eyes with reticular AF or pseudodrusen, 28 had both, 4 had reticular AF only, and 2 had reticular pseudodrusen only. CONCLUSIONS: There are clear relationships between AF patterns and clinical AMD status. In early AMD, FIAF's colocalization with large, soft drusen and hyperpigmentation is several times greater than chance, suggesting linked disease processes. In advanced atrophic AMD, FIAF is found mostly adjacent to drusen and GA, suggesting that dispersal of drusen-associated lipofuscin is a marker of atrophic disease progression. In the neovascular case, a large group of fellow eyes have no FIAF abnormalities, suggesting that lipofuscin is not a major determinant of CNV. However, reticular hypoautofluorescence, consistent with widespread inflammatory damage to the RPE, appears to be a highly sensitive imaging marker for the disease that determines reticular pseudodrusen and is strongly associated with CNV.     

Laser prophylaxis for age-related macular degeneration

BACKGROUND: Age-related macular degeneration (AMD) is the most common cause of severe and irreversible vision loss among people 50 years of age or older in many Western countries. Most of the available treatments for AMD are intended for the late stage, specifically for choroidal neovascularization (CNV). Effective preventive treatments could have an even greater impact on the vision of the millions of people at risk for vision loss from AMD. Drusen are typically the earliest lesions seen in patients with AMD and precede the development of CNV. In 1973, Gass noted the disappearance of drusen in eyes that received laser photocoagulation, which led to the hypothesis that laser-induced drusen reduction could alter the natural course of AMD. METHODS: We reviewed relevant articles found through a search of MEDLINE through February 2005 by means of the following key words, alone or in combination: drusen, laser, photocoagulation, age-related macular degeneration, macula and choroidal neovascularization. RESULTS: Reports ranging from individual cases and case series to randomized controlled pilot studies have described various laser treatment protocols and their effects on eyes with high-risk drusen but no neovascular changes. These reports provide evidence that laser photocoagulation can induce drusen reduction. Although some investigators have reported a corresponding improvement in visual function, others have found no change or even worsening. The results in several of the larger randomized controlled studies suggest that CNV may occur at an increased rate in laser-treated eyes with high-risk drusen in patients who have neovascular AMD in the other eye. The long-term effects of laser treatment in patients with high-risk drusen in both eyes and no neovascular changes have yet to be determined. INTERPRETATION: The outcome of clinical trials such as the Prophylactic Treatment of Age-Related Macular Degeneration and the Complications of Age-Related Macular Degeneration Prevention Trial will help to determine the role of laser prophylaxis in patients with AMD.     

Drusen characteristics in patients with exudative versus non-exudative age-related macular degeneration

The drusen characteristics of 38 eyes from 38 patients with bilateral drusen associated with age-related macular degeneration (AMD) were compared in a masked fashion to 89 fellow eyes from 89 patients with unilateral exudative AMD (disciform scarring or choroidal neovascularization). The average age of the drusen group (67.4 years) was significantly less (P = 0.01) than the average age of the unilateral exudative group (72.6 years). Multiple logistic regression was used to compare the drusen characteristics in the two groups, controlling for the age and sex of the patients. Among patients 75 years of age and younger, patients with confluent drusen had an increased risk of having a fellow eye with exudative AMD compared with patients without confluent drusen. Among patients older than 75 years of age, confluent drusen did not significantly differentiate the two study groups, although confluent drusen in this older age group were more often associated with the bilateral drusen group. Focal hyperpigmentation of the retinal pigment epithelium was also associated with the unilateral exudative group. These drusen characteristics should be evaluated in future prospective studies designed to determine which eyes with drusen are at greatest risk for developing the blinding complications of choroidal neovascularization.     

Evaluating pulsatile ocular blood flow analysis in normal and treated glaucomatous eyes

PURPOSE: To evaluate pulsatile ocular blood flow (POBF) analysis in normal subjects and glaucoma patients by comparison of POBF measurements with functional (as determined by visual field [VF]) and structural (as determined by optical coherence tomography [OCT]) measures. DESIGN: Prospective, cross-sectional study. METHODS: Forty-one eyes of 24 consecutive glaucoma patients and 20 eyes of 10 healthy subjects were studied; POBF analysis was performed on all subjects at the same visit as VF testing and OCT retinal nerve fiber layer (NFL) thickness measurement. The mean results of normal and glaucomatous eyes were compared for each method. Correlation between measurements obtained with each modality and the discriminating power using receiver operator characteristic curves was tested. RESULTS: The mean POBF (standard deviation [SD]) in the normal group was 1,010.4 (292.8) microl/min and 989.3 (305.5) microl/min in the glaucoma group (P =.90). Significant differences between groups were found for VF mean deviation and pattern standard deviation (P =.02, P =.004, respectively) and OCT mean NFL thickness (P <.0001). No correlation was found between POBF parameters and intraocular pressure, VF, or OCT variables except for intraocular pressure in glaucoma group (r = -.43, P =.003). The area under the receiver operator characteristic curves was higher for VF indexes and OCT mean NFL thickness than POBF parameters for distinguishing between normal and glaucomatous eyes. CONCLUSIONS: The wide range of normal values and the low discriminating power of POBF between normal and glaucomatous eyes limits the clinical use of the device for glaucoma patients.