Choroidal ischemia after photodynamic therapy with verteporfin for choroidal neovascularization

Half-Dose Photodynamic Therapy as a Novel Treatment Protocol for Circumscribed Choroidal Hemangioma

We present a case series of four patients with circumscribed choroidal hemangioma (CCH) treated with half-dose PDT, proposing this as a novel treatment protocol. Four patients with CCH were included, and then evaluated using multimodal imaging, including optical coherence tomography (OCT), fluorescein angiography, indocyanine green angiography, fundus autofluorescence, and ultrasound following treatment with half-dose and full-fluence PDT. Following half-dose PDT, all patients showed significant shrinkage of the hemangioma, functional improvement, and decrease of intra- and sub-retinal fluid. All patients remained stable after a single PDT treatment, with a follow-up of up to 60 months. No side effects were shown. This is the first report showing long term efficacy of half-dose PDT treatment in cases with CCH. The outcomes from this pilot study are comparable with results using full dose PDT protocols and it can be considered as a viable treatment option for CCH during the ongoing global verteporfin shortage.

Dose-Related Structural Effects of Photodynamic Therapy on Rabbit Choroidal Structure

INTRODUCTION

Photodynamic therapy with verteporfin (vPDT) has been shown to be effective against central serous chorioretinopathy (CSC) and was the preferred therapeutic for CSC treatment. However, alterations in choroidal structure after PDT were reported, and these effects were dose-dependent. This study aimed to compare the changes in choroidal structure after PDT with different doses of verteporfin in rabbits and may provide individualized therapeutic guidance for patients who failed to respond to initial half-dose vPDT.

METHODS

The full dose of verteporfin used in CSC was 6 mg/m2, which was used in patients with neovascular age-related macular degeneration. Laser fluence was 50 J/cm2 (irradiance, 600 mW/cm2, 83 s). There were 4 different dose groups in this study (100%, 70%, 50%, and 30%). The alterations were examined at 1 day, 1 week, and 1 month after vPDT using color fundus imaging, indocyanine green angiography, and histopathology analysis.

RESULTS

Various degrees of choroidal alterations were demonstrated at different dose groups. Examinations on day 1 showed that gradually reduced verteporfin dose tended to decrease photochemical reactions to the choroid in terms of the number of occlusion vessels and area of the lesion. After 1 month, choroid vessel alteration persisted in high-dose groups (100% and 70%); nevertheless, alterations of low-dose groups (50% and 30%) returned to normal.

CONCLUSIONS

vPDT can induce photochemical reactions of the choroid, high dose causes permanent change, and low dose causes recoverable change. The dose-dependent alterations need to be considered for the individual therapeutic plan according to the situation of a patient with CSC.

Decrease in choroidal blood flow after half and one-third dose verteporfin photodynamic therapy for chronic central serous chorioretinopathy

Background

The effect of various reduced doses of verteporfin photodynamic therapy (PDT) on choroidal blood flow in chronic central serous chorioretinopathy (CSC) remains unclear. Therefore, this study aimed to evaluate choroidal blood flow after half-dose PDT (1/2PDT) and one-third dose PDT (1/3PDT) with verteporfin for chronic CSC using laser speckle flowgraphy and spectral-domain optical coherence tomography.

Methods

Twenty-seven eyes of 27 patients with serous retinal detachment (SRD) caused by chronic CSC for more than 6 months were included in this study. Patients were divided into the 1/2PDT (n = 12; January 2018 to July 2019) and 1/3PDT (n = 15; August 2016 to December 2017) groups based on the treatment period. The best-corrected visual acuity (BCVA), central retinal thickness (CRT), central choroidal thickness (CCT), and mean blur rate in the macular area (m-MBR) and optic nerve head (ONH-MBR) were obtained using laser speckle flowgraphy and evaluated at baseline (pre-treatment), and 2 weeks, 1 month, 3 months, and 6 months after treatment.

Results

We found that SRD disappeared after 1 month in 92 and 93% of patients’ eyes in the 1/2PDT and 1/3PDT groups, respectively. Recurrence of SRD was observed in one eye at the 6-month follow-up after 1/2PDT and two eyes at the 3-month follow-up after 1/3PDT. No significant improvement was observed in baseline BCVA in the 1/3PDT and 1/2PDT groups. The average m-MBR against baseline significantly decreased at 2 weeks and 1, 3, and 6 months in the 1/2PDT group. The average m-MBR against baseline decreased significantly only at the 2 weeks follow-up in the 1/3PDT group. The average rate of change in the CCT against baseline decreased significantly throughout for up to 6 months in the 1/2PDT group and for up to 3 months in the 1/3PDT group. No significant fluctuation was observed in the ONH-MBR.

Conclusions: Here, PDT significantly affected choroidal blood flow depending on the verteporfin dose in chronic CSC.

Trial registration

This trial was retrospectively registered (UMIN000026850; Approval date 03/04/2017).

Clinical Factors Associated with Low-Contrast Visual Acuity after Reduced-Fluence Photodynamic Therapy in Patients with Resolved Central Serous Chorioretinopathy and Good Baseline Visual Acuity

This retrospective study was conducted to investigate the clinical factors associated with low-contrast visual acuity after reduced-fluence photodynamic therapy (RFPDT) in patients with resolved central serous chorioretinopathy (CSC) and good baseline visual acuity. A total of 45 eyes of 45 patients with resolved CSC at post-RFPDT and best-corrected visual acuity of >1.0 (logarithm of the minimal angle of resolution [logMAR], 0) at baseline were examined. Visual acuities of both eyes were measured at four contrast levels (100%, 25%, 12%, and 6%) at post-RFPDT. The low-contrast visual acuity (6%, 12%, and 25%) was significantly lower than the 100% contrast visual acuity in the affected eyes. Visual acuities of affected eyes were significantly worse than those of fellow eyes at any contrast levels. The degree of changes in 6% and 100% contrast visual acuities was significantly greater in affected eyes than that in fellow eyes (p < 0.05). The 6% contrast visual acuities in affected eyes at post-RFPDT were significantly associated with the symptom duration (p < 0.05). Patients with a long duration of symptoms might have disturbed low-contrast visual acuities at post-RFPDT even if their baseline visual acuities were good.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY-GUIDED PHOTODYNAMIC THERAPY FOR ACUTE CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To compare the anatomic results of optical coherence tomography angiography (OCTA)-guided half-dose photodynamic therapy (PDT) versus indocyanine green angiography (ICGA)-guided PDT in eyes with acute central serous chorioretinopathy.

METHODS

This study is a prospective, single-center, noninferiority, double-masked, randomized, controlled clinical trial. Fifty-one eyes of 45 patients with acute central serous chorioretinopathy were recruited, and randomized to an ICGA-guided group and an OCTA-guided group. The primary outcome measures were the rates of complete subretinal fluid (SRF) resolution at 1 month and 3 months.

RESULTS

Forty-six eyes of 40 patients finished the follow-up and were analyzed. In the OCTA-guided group, the SRF was completely resolved in 13 (56.5%) eyes within 1 month and in 21 (91.3%) eyes within 3 months. In the ICGA-guided group, the SRF was resolved in 16 (69.6%) of the eyes within 1 month and in 22 (95.7%) of the eyes by 3 months. Optical coherence tomography angiography-guided PDT was demonstrated noninferior to ICGA-guided PDT for SRF resolution rate at 3 months (P = 0.016), but not at 1 month (P = 0.311) for acute central serous chorioretinopathy patients. Subretinal fluid did not recur in any of the eyes in the OCTA-guided group, but did recur in 2 eyes (8.7%) of the ICGA-guided group during the 3-month follow-up period.

CONCLUSION

Optical coherence tomography angiography-guided PDT seemed to be noninferior to ICGA-guided PDT for resolution of SRF at 3 months in eyes with acute central serous chorioretinopathy.

Comparison between the outcomes of fluorescein angiography-guided and indocyanine green angiography-guided half-time photodynamic therapy for central serous chorioretinopathy

BACKGROUND AND OBJECTIVES

This study aimed to compare the efficacy of fluorescein angiography (FA)-guided and indocyanine green angiography (ICGA)-guided half-time photodynamic therapy (PDT) for central serous chorioretinopathy (CSC).

SUBJECTS AND METHODS

Medical records of 61 eyes of 61 CSC patients who underwent half-time PDT were retrospectively reviewed. The irradiation area was determined using information from FA or ICGA with physicians' discretion. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), subfoveal choroidal thickness (SCT), and resolution of subretinal fluid (SRF) were evaluated at baseline and 1, 3, 6, and 12 months after PDT.

RESULTS

A total of 29 and 32 eyes received FA-guided PDT (irradiation area, 2898.3 ± 705.7 μm) and ICGA-guided PDT (irradiation area, 4993.8 ± 333.1 μm), respectively. A significant improvement in the mean BCVA was found at 1 month in the FA-guided group (P = 0.02), but not in the ICGA-guided group (P = 0.88). BCVA was significantly improved in both groups at 3, 6, and 12 months with no significant intergroup difference at any time points. CRT and SCT were significantly reduced in both groups at all time points with no significant intergroup differences. No significant intergroup differences were observed in the rate of recurrence and persistent SRF. However, there was a significant difference between groups in the rate of recurrence and/or persistent SRF (P = 0.04). Multivariate analysis revealed that choice of FA-guided was significantly associated with recurrence and/or persistent SRF (P = 0.04).

CONCLUSION

Half-time PDT with ICGA-guided irradiation spot might be more effective than that with FA-guided in treating CSC patients in complete resolution of SRF.

Impact of methylenetetrahydrofolate reductase C677T polymorphism on the efficacy of photodynamic therapy in patients with neovascular age-related macular degeneration

The most severe visual impairments due to age-related macular degeneration (AMD) are frequently caused by the occurrence of choroidal neovascularization (CNV). Although photodynamic therapy with verteporfin (PDT-V) is currently a second-line treatment for neovascular AMD, it can be conveniently combined with drugs acting against vascular endothelial growth factor (anti-VEGF) to reduce the healthcare burden associated with the growing necessity of anti-VEGF intravitreal re-injection. Because the common 677 C > T polymorphism of the methylenetetrahydrofolate reductase gene (MTHFR-C677T; rs1801133) has been described as predictor of satisfactory short-term responsiveness of AMD-related CNV to PDT-V, we retrospectively examined the outcomes of 371 Caucasian patients treated with standardized, pro-re-nata, photodynamic regimen for 24 months. Responder (R) and non-responder (NR) patients were distinguished on the basis of the total number of scheduled PDT-V (TN-PDT-V) and change of best-corrected visual acuity (∆-BCVA). The risk for both TN-PDT-V and ∆-BCVA to pass from R to NR group was strongly correlated with CT and TT genotypes of MTHFR-C677T variant resulting, respectively, in odd ratios of 0.19 [95% CI, 0.12-0.32] and 0.09 [95% CI, 0.04-0.21] (P < 0.001), and odd ratios of 0.24 [95% CI, 0.15-0.39] and 0.03 [95% CI, 0.01-0.11] (P < 0.001). These pharmacogenetic findings indicate a rational basis to optimize the future clinical application of PDT-V during the combined treatments of AMD-related CNV, highlighting the role of thrombophilia to be aware of the efficacy profile of photodynamic therapy.

Choroidal Watershed Zone and Growth of Polypoidal Choroidal Vasculopathy

PURPOSE

To investigate the topographic relationship between polypoidal choroidal vasculopathy (PCV) growth and choroidal watershed zones (CWZ) by using indocyanine green angiography (ICGA).

MATERIALS AND METHODS

We evaluated PCV lesions smaller than the CWZ at baseline and followed up more than 6 months. The CWZ was traced in the early phase ICGA at baseline. The vascular lesion of PCV was traced in baseline and follow-up ICGA. These traces were overlapped and topographic relationships between CWZs and PCV growth were evaluated.

RESULTS

Among 31 eyes of 31 patients, enlargement of a PCV lesion was observed in 20 patients (64.5%) at mean follow-up of 30.4 months (6-68 months). A topographical relationship between the CWZ and PCV growth was demonstrated in 14 eyes (70.0%), as the shape of the PCV lesion conformed to the boundary of the CWZ, and/or the growth of the branching vascular network was aligned to the direction of the CWZ extension to the periphery. Growth beyond the boundary of the CWZ was noted in 9 eyes (45.0%), however growth area was greater inside the CWZ than outside in all eyes. Of 15 eyes of extrafoveal lesion at baseline, 8 eyes in which the vascular lesion progressed to the fovea had the CWZ involving the fovea, whereas PCV in three eyes with an extrafoveal CWZ remained as a non-subfoveal disease after mean follow-up of 17.0 months (p = 0.019).

CONCLUSIONS

A subfoveal CWZ was related to PCV growth to the fovea. Topographical relationships between PCV growth and the CWZ suggest that choroidal circulation is a predisposition for PCV growth.

Half-dose Versus Half-time Photodynamic Therapy for Central Serous Chorioretinopathy

PURPOSE

To compare the efficacy of half-dose vs half-time photodynamic therapy (PDT) guided by fluorescein angiography (FA) for the treatment of central serous chorioretinopathy (CSC).

DESIGN

Two-center, retrospective, comparative case series.

METHODS

Sixty-one eyes with acute or chronic CSC involving fovea were recruited; 35 eyes received half-dose PDT and 26 eyes received half-time PDT. Improvement in best-corrected visual acuity (BCVA), resolution of subretinal fluid (SRF) demonstrated by optical coherence tomography (OCT), and recurrence of CSC after PDT were compared between the 2 groups.

RESULTS

The mean follow-up time after PDT was 14.8 ± 13.3 months. Both groups showed significant improvement in BCVA at months 1, 3, 6, and 12 after PDT (P < .05 for all times). Multiple regression analysis showed that PDT type was not correlated with visual improvement (P > .05 for all times). All eyes that received half-time PDT showed complete resolution of SRF within 6 months after PDT, but 3 eyes that received half-dose PDT had persistent SRF before loss to follow-up at months 5, 7, and 8 (P = .21 between 2 groups). Three of 32 eyes in the half-dose group and 2 of 26 eyes in the half-time group had recurrence of CSC during follow-up; all recurrent cases had complete SRF resolution after another PDT treatment. No adverse systemic or ocular side effects were observed in any cases.

CONCLUSIONS

Half-dose and half-time FA-guided PDT were both effective and safe in treating CSC and showed similar efficacy in visual improvement and SRF resolution.

Intravitreal Anti-vascular Endothelial Growth Factor for Newly Diagnosed Symptomatic Polypoidal Choroidal Vasculopathy with Extrafoveal Polyps

PURPOSE

To evaluate the 12-month outcome of anti-vascular endothelial growth factor (VEGF) treatment for extrafoveal polypoidal choroidal vasculopathy (PCV).

METHODS

This retrospective observational study included 32 eyes of 32 patients newly diagnosed with extrafoveal PCV (polyps located more than 500 µm from the center of the fovea). Patients were treated with intravitreal ranibizumab, bevacizumab, or both. The best-corrected visual acuity (BCVA) and central foveal thickness (CFT) at diagnosis and at 12 months were compared. Eyes were divided into two groups according to the presence of submacular hemorrhage. The BCVA in each group was compared at baseline and at 12 months.

RESULTS

During the 12-month study period, patients received an average of 4.0 ± 1.1 anti-VEGF injections. The BCVA at baseline, three-month post-diagnosis, and 12-month post-diagnosis was 0.59 ± 0.40, 0.34 ± 0.38, and 0.38 ± 0.38, respectively. The BCVA at 12 months was significantly better than the baseline value (p = 0.002). The CFT at baseline, three-month, and 12-month post-diagnosis was 477.1 ± 194.2 µm, 214.5 ± 108.8 µm, and 229.8 ± 106.1 µm, respectively. The CFT at 12 months was significantly lower than the baseline value (p < 0.001). A significant improvement in BCVA was noted in eyes with and without submacular hemorrhage (n = 13, p = 0.032 and n = 19, p = 0.007, respectively).

CONCLUSIONS

Anti-VEGF therapy was beneficial in extrafoveal PCV, regardless of the presence of submacular hemorrhage.

Half-dose verteporfin combined with half-fluence photodynamic therapy for chronic central serous chorioretinopathy

PURPOSE

This study evaluated the safety and efficacy of half-dose verteporfin combined with half-fluence photodynamic therapy (half-half photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC).

METHODS

This was a retrospective case series. Fourteen eyes with chronic CSC receiving half-half PDT were included in group 1. Another 28 eyes receiving half-dose verteporfin combined with standard fluence PDT were included in group 2 as a control group. Main outcome measures were the success rates, major complications, best-corrected visual acuity (BCVA), and central subfield foveal thickness (CFT) on optical coherence tomography (OCT) at 6 months in both groups. Success of treatment was defined as complete resolution of subretinal fluid on OCT after treatment without recurrence.

RESULTS

There was no significant difference between groups in their age, gender, duration of symptoms, baseline BCVA, baseline CFT, PDT spot size, and follow-up duration. The success rate was 64% (9/14 eyes) in group 1 and 93% (26/28 eyes) in group 2 at 6 months (P=0.031). No major complications were found in either group. Mean CFT showed significant reduction at 6 months in both groups (-115 μm and P<0.001 in group 1; -150 μm and P<0.001 in group 2). The mean BCVA in group 2 improved significantly (P<0.001) at 6 months. The mean BCVA in group 1 showed a trend of improvement but was not statistically significant (P=0.25) at 6 months.

CONCLUSIONS

Half-half PDT is a feasible treatment for chronic CSC. However, there was a lower success rate at 6 months compared with the control group.

Polypoidal choroidal vasculopathy exudation and hemorrhage: results of monthly ranibizumab therapy at one year

PURPOSE

To evaluate the efficacy and safety of monthly intravitreal injections of ranibizumab in patients with polypoidal choroidal vasculopathy (PCV) and active exudation or hemorrhage.

METHODS

A prospective, single practice, open label trial of monthly intravitreal ranibizumab (0.5 mg) injections for PCV in 13 eyes of 13 patients who completed the 1-year study. The primary outcome measure was stabilization of vision (loss of <15 ETDRS letters). Secondary outcome measures included incidence of ocular and systemic adverse events, changes in subretinal hemorrhage, central foveal thickness, and polypoidal complexes on indocyanine green angiography at 1 year.

RESULTS

No patient lost ≥ 15 letters in visual acuity at 1 year. Three patients (23%) gained ≥ 15 letters at 12 months. Subretinal hemorrhage resolved in 9/9 eyes (100%). Macular edema improved in 5/5 eyes (100%). Subretinal fluid completely resolved in 4/9 eyes (44%), decreased in 2/9 eyes (22%), and increased in 3/9 eyes (33%). Polypoidal complexes decreased in 5/13 eyes (38%).

CONCLUSION

Continuous monthly intravitreal ranibizumab decreases leakage and hemorrhage in eyes with exudative and hemorrhagic complications of PCV. Branching vascular networks persisted, and polypoidal complexes decreased in only 5/13 (38%) eyes with continuous antiangiogenic therapy at 1 year.

Differential sensitivity of choroidal endothelial, retinal ganglion, and retinal pigment epithelial cells in vitro to proton radiation

PURPOSE

To evaluate the differential sensitivity of choroidal endothelial, retinal pigment epithelial, and retinal ganglion cells to escalating doses of proton beam radiation and to establish a safe dose range for the management of choroidal neovascularization associated with age-related macular degeneration (AMD).

DESIGN

Laboratory investigation.

METHODS

Proliferating simian choroidal endothelial cells (RF/6A), differentiated rat retinal ganglion cells (RGC-5), and serum-starved human retinal pigment epithelial cells (ARPE-19) were exposed to 2, 4, 8, and 12 cobalt gray equivalent of proton beam radiation and cell viability was quantified on day 9. Reactive oxygen species levels were analyzed.

RESULTS

Significant decline of choroidal endothelial cell viability was noted as dose escalated from 4 to 8 cobalt gray equivalent with maximum effect observed at 12 cobalt gray equivalent. RGC-5 and ARPE-19 cell count decreased to 95% and 62.7% at 8 cobalt gray equivalent, respectively. Sub-analysis between 4 and 8 cobalt gray equivalent radiation revealed significant decrease in choroidal endothelial cell viability (43.1% at 7 cobalt gray equivalent and 32.3% at 8 cobalt gray equivalent of radiation). Correspondingly, RGC-5 and ARPE-19 cells did not show decrease in cell count or viability. Reactive oxygen species levels significantly increased in radiation-treated choroidal endothelial cells (8.3%-11.9%).

CONCLUSIONS

At 6-8 cobalt gray equivalent proton beam radiation, retinal ganglion and retinal pigment epithelial cells are preserved while choroidal endothelial cells are completely inhibited. This dosage offers optimum therapeutic safety window for treatment using proton beam radiation for exudative AMD.

Choroidal thickness following extrafoveal photodynamic treatment with verteporfin in patients with central serous chorioretinopathy

PURPOSE

To evaluate the effect of verteporfin photodynamic treatment (PDT) on choroidal thickness in patients with central serous chorioretinopathy (CSC).

METHODS

Choroidal thickness was measured with enhanced depth imaging- optical coherence tomography (EDI-OCT) before and after verteporfin PDT (full-dose verteporfin, half-light dose) in 16 eyes in 16 patients with serous detachment of the fovea secondary to extrafoveal angiographic fluorescein leakage. Treatment was confined to the area of leakage, whereas choroidal thickness before and after treatment was assessed over a larger area of the fundus using OCT.

RESULTS

Complete resolution of the serous detachment was seen in all 16 eyes within 1 month of extrafoveal PDT, while choroidal thickness in the area where PDT was applied decreased from 407 μm [mean; 95% confidence interval (CI(95) ) 356-458 μm] to 349 μm (mean; CI(95) 300-399 μm; p < 0.0001), and subfoveal choroidal thickness was reduced from 421 μm (mean; CI(95) 352-489 μm) to 346 μm (mean; CI(95) 278-414 μm; p = 0.0001). Initially, subfoveal choroidal thickness was significantly increased in the treated eye compared with the healthy fellow eye (mean 324 μm; CI(95) 273-376 μm; p = 0.0003), but after treatment, the difference was not significant.

DISCUSSION

Photodynamic therapy of active CSC was followed by choroidal thickness reduction, not only locally but also at considerable distance from the treated area. Thus, the process that causes choroidal thickening in CSC appears to spread laterally within the choroid.

Enhanced depth imaging optical coherence tomography

Imaging the choroid with conventional commercial spectral-domain optical coherence tomography (SD-OCT) has been difficult, mainly because of difficulty in signal transmission beyond the retinal pigment epithelium. A recent modification to the standard technique, termed enhanced depth imaging optical coherence tomography (EDI-OCT), was able to image the choroid with reasonable clarity using commercial SD-OCTs. The aim of this article was to review the technique, principle, recent findings, and possible future developments regarding EDI-OCT. A MEDLINE search on all published articles on EDI-OCT was performed up to December 2010. The principle behind EDI-OCT was discussed. Modification to the conventional technique in image acquisition was described and illustrated with figures. EDI-OCT findings in various retinal and choroidal diseases were discussed. Advantages and disadvantages were also discussed. EDI-OCT has proved to be a promising novel technique in imaging the choroid.

Genetic predictors of response to photodynamictherapy

In Western countries, therapeutic management of patients affected by choroidal neovascularization (CNV) secondary to different typologies of macular degeneration represents a major health care problem. Age-related macular degeneration is the disease most frequently associated with CNV development. Schematically, CNVs can be distinguished into classic and occult subtypes, which are characterized by variable natural history and different responsiveness to some therapeutic procedures. At present, the dramatic vision loss due to CNV can be mainly treated by two interventional strategies, which are utilizable in either single or combined modalities: photodynamic therapy with verteporfin (PDT-V), and intravitreal administration of drugs acting against vascular endothelial growth factor. The combined use of PDT-V and anti-angiogenic drugs represents one of the most promising strategies against neovascular macular degeneration, but it unavoidably results in an expensive increase in health resource utilization. However, the positive data from several studies serve as a basis for reconsidering the role of PDT-V, which has undergone a renaissance prompted by the need for a more rational therapeutic approach toward CNV. New pharmacogenetic knowledge of PDT-V points to exploratory prospects to optimize the clinical application of this intriguing photothrombotic procedure. In fact, a Medline search provides data regarding the role of several single nucleotide polymorphisms (SNPs) as genetic predictors of CNV responsiveness to PDT-V. Specifically, correlations between SNPs and different levels of PDT-V efficacy have been detected by examining the gene variants influencing (i) thrombo-coagulative pathways, i.e. methylenetetrahydrofolate reductase (MTHFR) 677C>T (rs1801133), factor V (F5) 1691G>A (rs6025), prothrombin (F2) 20210G>A (rs1799963), and factor XIII-A (F13A1) 185G>T (rs5985); (ii) complement activation and/or inflammatory processes, i.e. complement factor H (CFH) 1277T>C (rs1061170), high-temperature requirement factor A1 (HTRA1) promoter -512G>A (rs11200638), and two variants of the C-reactive protein (CRP) gene (rs2808635 and rs876538); and (iii) production and bioavailability of vascular endothelial growth factor (VEGFA -2578C>A [rs699947] and rs2146323). This article critically evaluates both the clinical plausibility and the opportunity to utilize the most important SNP-response interactions of PDT-V for an effective upgrade of the current anti-CNV therapeutic scenario. In addition, the pharmacogenetics of a very severe post-PDT-V adverse event, i.e. a decrease in acute vision, is briefly discussed. A comprehensive appraisal of the findings reviewed in this article should be carefully considered to design future trials aimed at verifying (after proper genotypic stratification of the enrolled patients) whether these innovative pharmacogenetic approaches will be able to improve the multifaceted interventional management of neovascular macular degeneration.

Photodynamic therapy of symptomatic choroidal nevi

Purpose:

To evaluate the role of photodynamic therapy (PDT) for patients with symptomatic choroidal nevi involving the fovea or located near the fovea with subretinal fluid extending to the fovea.

Materials and Methods:

Retrospective review of five patients who underwent PDT for choroidal nevi at two separate centers in Ankara and Barcelona.

Results:

The mean initial logMAR visual acuity was 0.5 (range: 0 to 1.5). The mean largest tumor base diameter was 3.2 mm (range: 2.1–4.5 mm) and the mean tumor thickness was 1.1 mm (range: 0.7–1.6 mm). The mean number of PDT sessions was 1.6 (range:1–3). The mean final tumor thickness was 1.0 mm (range: 0–1.6 mm) at a mean follow-up of 19 months (range: 12–32 months). The mean final logMAR visual acuity was 0.4 (range: 0–1.5). Subfoveal fluid disappeared or decreased significantly in 4 of 5 eyes (80%) after PDT.

Conclusions:

PDT led to resolution of subretinal fluid with preservation of visual acuity in many symptomatic choroidal nevi in this study. Careful case selection is important as PDT of indeterminate pigmented tumors may delay the diagnosis and treatment of an early choroidal melanoma and thereby increase the risk for metastasis.

Evaluation of proton beam radiation sensitivity of proliferating choroidal endothelial and retinal ganglion cells with clonogenic assay

CONTEXT

Proton beam therapy offers the advantage of precise delivery with limited damage to the healthy tissue and is being tested in the management of exudative age-related macular degeneration (AMD). However, the dosages tested are empirical and not based on preclinical studies.

OBJECTIVE

In this study we evaluated the effects of varying doses of proton beam radiation on choroidal endothelial cells (CECs) and retinal ganglion cells (RGCs) using clonogenic assay to determine differential sensitivity.

MATERIALS AND METHODS

Each cell type has different efficiency to replicate (plating efficiency (PE)). PE of CEC (RF/6A) and RGC (RGC-5) grown in culture flasks was determined by plating 250 cells each (without any treatment) and counting the number of colonies after 13 days. Radiation induced sensitivity was determined by exposing the semi-confluent RF/6A and RGC-5 cells to proton beam at the doses of 0 (control), 2, 4, 8 and 12 cobalt gray equivalent (CGE). The ability of the cells to repair and replicate to form colonies were analyzed 13 days after radiation with crystal violet stain and the survival ratio was calculated. The significance of survival was analyzed using ANOVA (Graphpad Instat.3).

RESULTS

The PE of CEC and RGC was 12.96 ± 0.29% and 40.7 ± 1.48%, respectively. A survival ratio of CEC at 2, 4, 8 and 12 CGE proton radiation was 66.0 ± 8.6%, 44.3 ± 6.5%, 7.6 ± 0.3% and 1.14 ± 0.06% on exposure to 2, 4, 8 and 12 CGE proton radiation, respectively, p < 0.01). Survival ratio of RGC was 71.1 ± 22.4% (p = 0.05), 40.2 ± 7.9%, 8.89 ± 2.6% and 0.78 ± 0.31% at 2, 4, 8 and 12 CGE dosages (p < 0.001).

DISCUSSION

CEC showed dose-dependent decrease in survival rate with values attaining significance at all radiation dosages. In contrast, RGC was comparatively radio resistant and were able to replicate at lower doses and sensitive at higher doses after proton beam radiation.

CONCLUSION

Since CECs proliferate during neovascularization, this clonogenic assay is a useful assay to assess the sensitivity of CEC to radiation. This study identified that CEC were more sensitive to proton beam radiation than RGC at all doses. This may provide a therapeutic window for administration of proton beam radiation in the management of AMD.

Combined treatment of photodynamic therapy and bevacizumab for choroidal neovascularization secondary to age-related macular degeneration

Purpose

To evaluate the outcome of a combined photodynamic therapy and intravitreal injection of bevacizumab in choroidal neovascularization secondary to age-related macular degeneration.

Methods

Photodynamic therapy (PDT) was administered to 28 eyes followed by 3 consecutive bevacizumab injections. Patients were followed-up for more than 12 months. At baseline, 1, 3, 6, and 12 months post PDT, visual acuity (VA) and central macular thickness were measured using optical coherence tomography.

Results

The mean VA was significantly improved from logarithm of the minimal angle of resolution 0.86 at baseline to 0.69 at 1 month (p = 0.011), 0.63 at 3 months (p = 0.003), 0.64 at 6 months (p = 0.004) and 0.60 at 12 months (p < 0.001). Central macular thickness decreased significantly from 328.3 µm at baseline to 230.0 µm at 6 months and 229.9 µm at 1 year (p < 0.001). Reinjection mean number was 0.4 for 6 months and 0.8 for 12 months. By 1 year, retreatment was performed in 10 eyes (36%).

Conclusions

PDT combined with three consecutive intraviteal bevacizumab injections was effective in improving VA and reducing central macular thickness.

Severe decrease in visual acuity with choroidal hypoperfusion after photodynamic therapy

Background

Photodynamic therapy (PDT) is considered a selective method of treatment which works in areas of choroidal neovascularization (CNV); however, there are reports of choroidal hypoperfusion after PDT. This paper presents a clinical case of choroidal circulation disturbances caused by PDT, accompanied by CNV progression.

Case Report

The patient, a 75-year-old woman, was qualified for PDT in the right eye – first treatment due to progression of occult CNV. Best corrected visual acuity (BCVA) in the right eye at baseline was +0.3 logMAR. After PDT, a rapid decrease in visual acuity to +0.7 logMAR in the right eye was observed, central choroidal hypoperfusion in fluorescein angiography (FA) with subretinal fluid appeared and, as a consequence, progression of neovascular age-related macular degeneration (AMD). After stabilizing the local state through conservative therapy, a decision was made to treat the right eye with intravitreal injections of vascular endothelial growth factor (VEGF) inhibitor. During a 12-month period of observation, 7 doses of ranibizumab were administered. A regression in activity of wet AMD was observed, with visual acuity of +0.6 logMAR.

Conclusions

Choroidal circulation disturbance after PDT is possible and has to be taken into account. Sporadically, it can lead to an acute decrease in visual acuity and local state. After stabilization of AF and optical coherence tomography imaging, further treatment of neovascular AMD with intravitreal injections of anti-VEGF agents should be considered.

Comparison of efficacy and safety between half-fluence and full-fluence photodynamic therapy for chronic central serous chorioretinopathy

PURPOSE

To compare the efficacy and safety of half-fluence photodynamic therapy (PDT) and conventional PDT in chronic central serous chorioretinopathy.

METHODS

A multicenter retrospective comparison study. Retrospective review of 60 patients including 29 patients (34 eyes) who received half-fluence PDT and 31 patients (33 eyes) who received conventional PDT for the treatment of chronic central serous chorioretinopathy. Best-corrected visual acuity, central fovea retinal thickness and resolution of subretinal fluid on optical coherence tomography, and choroidal perfusion decrease on indocyanine green angiography were assessed. Choriocapillaris perfusion decrease was quantified as mean gray value ratio of treated and nontreated areas using commercial imaging software.

RESULTS

Treatment success without recurrence was achieved in 32 of 34 eyes (94.1%) treated with half-fluence PDT and 33 of 33 eyes (100%) treated with conventional PDT (P = 0.493). There was no difference in final best-corrected visual acuity (logarithm of the minimal angle of resolution) between the 2 groups (0.17 ± 0.32 vs. 0.21 ± 0.39; P = 0.603). Choriocapillaris perfusion decrease quantified from post-PDT indocyanine green angiography was significantly more severe in the conventional PDT group (P = 0.006), and it showed a positive correlation with retinal thinning after PDT (R = 0.380; P < 0.001).

CONCLUSION

Half-fluence PDT is as effective as conventional PDT, while minimizing the deleterious effect on choriocapillaris perfusion and retinal thickness.

Choroidal nonperfusion with significant subretinal exudation after PDT of predominantly classic CNV: an OCT and FFA study

PURPOSE

Despite the increasing use of antivascular endothelial growth factors (anti-VEGF), photodynamic therapy (PDT) with Verteporfin is still considered the gold standard treatment of subfoveal and juxtafoveal classic choroidal neovascularization (CNV).

METHODS

Case report.

RESULTS

The authors report a case of a 72-year-old man who developed choroidal nonperfusion and significant subretinal fluid formation with associated severe visual loss following PDT of predominantly classic juxtafoveal CNV.

CONCLUSIONS

Although reported separately, these two complications have not been previously reported to occur in association after PDT treatment of classic CNV and may represent exaggeration of normal events occurring after PDT.

Subfoveal choroidal neovascularization in a patient with hemicentral vein occlusion

The association between choroidal neovascularization (CNV) and retinal vein occlusive disease is uncommon. Before the introduction of anti-vascular endothelial growth factor (VEGF) drugs, photodynamic therapy (PDT) was used, with conflicting functional results. We report a case of a 69-year-old male patient who came to our attention for macular edema in hemiretinal vein occlusion. Fluorescein angiogram showed presence of venous collaterals, but the pattern of the edema was atypical; optical coherence tomography (OCT) and indocyanine green angiography (ICG) were used to confirm the diagnosis of CNV. A chorio-retinal shunt was demonstrated. The autofluorescence technique was used to predict the risk of CNV in the fellow eye. PDT was performed twice, but after the second cycle, patient developed choroidal ischemia and the visual outcomes were poor. The temporal course of CNV, the presence of a chorio-retinal shunt, and the autofluorescence pattern in the fellow eye let us to speculate that the CNV was related to the vascular occlusive process. We can speculate that the overexpression of VEGF induced by local ischemia and inflammation can make these patients more likely to have CNV. However, to our knowledge, there are no accurate estimates of the incidence of CNV in other retinal vascular diseases, such as diabetic retinopathy.

Predictive role of C677T MTHFR polymorphism in variable efficacy of photodynamic therapy for neovascular age-related macular degeneration

Age-related macular degeneration (AMD) complicated by subfoveal choroidal neovascularization (CNV) is the leading cause of severe central blindness in developed countries. AMD-related CNVs are distinguishable in classic and occult subtypes, characterized by variable natural history and different responsiveness to therapeutic procedures. Combined and repeated use of photodynamic therapy with verteporfin (PDT-V) and antiangiogenic drugs represents the most promising strategy against neovascular AMD, but it is unavoidably associated with mounting health-resource utilization. Predictive correlations between peculiar coagulation-balance gene variants and different levels of post-PDT-V benefit have recently been documented in Caucasians with AMD-related CNVs. In particular, methylenetetrahydrofolate reductase C677T substitution, a common thrombophilic folate pathway genotypic polymorphism, influences a better CNV responsiveness to PDT-V in classic- but not in occult-CNV cases. These pharmacogenetic findings indicate the opportunities to optimize the eligibility criteria of PDT-V and/or to perform this intriguing therapy in a customized manner, for finally minimizing the socio-economic burden of neovascular AMD.

Half-dose verteporfin photodynamic therapy for acute central serous chorioretinopathy: one-year results of a randomized controlled trial

OBJECTIVE

To evaluate the efficacy of photodynamic therapy (PDT) with half-dose verteporfin for treating acute central serous chorioretinopathy (CSC).

DESIGN

Prospective, double-masked, placebo-controlled, randomized clinical trial.

PARTICIPANTS AND CONTROLS

Sixty-three eyes of 63 patients with acute symptomatic CSC of 3 months' duration or less were recruited. Forty-three eyes were randomized to indocyanine green angiography (ICGA)-guided PDT with half-dose (3 mg/m(2)) verteporfin and 21 eyes were randomized to placebo.

INTERVENTION

Patients in the verteporfin group received an infusion of half-dose verteporfin over 8 minutes, followed by ICGA-guided PDT 10 minutes from the start of infusion. Laser was applied for 83 seconds covering the choroidal abnormalities observed in ICGA, with a maximum laser spot size of 4500 mum.

MAIN OUTCOME MEASURES

The primary outcome measure was the proportion of eyes with absence of subretinal fluid at the macula at 12 months. Secondary outcome measures included changes in mean logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA), subjective symptoms, optical coherence tomography (OCT) results, central foveal thickness (CFT), and angiographic findings during the 12-month study period.

RESULTS

Thirty-nine patients in the verteporfin group and 19 patients in the placebo group completed 12 months of follow-up. Thirty-seven (94.9%) eyes in the verteporfin group compared with 11 (57.9%) eyes in the placebo group showed absence of subretinal fluid at the macula at 12 months (P = 0.001). The mean logMAR BCVA at 12 months was significantly better in the verteporfin group compared with the placebo group: -0.05 and 0.05, respectively (P = 0.008). All 39 (100%) verteporfin-treated eyes had stable or improved vision, compared with 15 (78.9%) eyes in the placebo group (P = 0.009). The mean OCT CFT for the verteporfin group also was significantly lower compared with the placebo group at 12 months (P = 0.001). No ocular or systemic adverse event was encountered in the study.

CONCLUSIONS

Photodynamic therapy with half-dose verteporfin is effective in treating acute symptomatic CSC, resulting in a higher proportion of patients with absence of exudative macular detachment and better visual acuity compared with placebo.