Relationships between clinical measures of visual function and anatomic changes associated with bevacizumab treatment for choroidal neovascularization in age-related macular degeneration

Review of Fibrosis in Neovascular Age-Related Macular Degeneration

PURPOSE

To report the diagnosis and definitions, epidemiology, risk factors, and visual outcomes of fibrosis in neovascular age-related macular degeneration (nAMD).

DESIGN

Systematic review and meta-analysis.

METHODS

The review was performed using the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Observational studies and randomized controlled trials were included.

RESULTS

Identification of fibrosis is challenging. Optical coherence tomography angiography and polarization-sensitive optical coherence tomography represent novel options in multimodal imaging. The prevalence of fibrosis at baseline, 12, 24, and 60 months was 13%, 32%, 36%, and 56%, respectively. Approximately 60% of the fibrosis burden in nAMD at 5 years was present in the first year of treatment. Fibrosis development was highest in the first 12 months and slowed down over time. The risk factors of fibrosis included classic choroidal neovascularization (CNV), intra-retinal fluid, hemorrhage, hyperreflective material, CNV lesion size, and retinal thickness. Sub-retinal fluid and pigment epithelial detachment may be protective. Treatment-associated factors included disease activity and time to diagnosis. At baseline, the best corrected visual acuity in eyes with fibrosis was poorer than in eyes without fibrosis (-18.50 letters); this difference became larger at 12 months despite treatment (-26.86 letters).

CONCLUSIONS

There is a need to identify effective treatment strategies for fibrosis and to closely monitor at-risk patients. More studies involving multimodal imaging are required to clarify the definitions and grading criteria for fibrosis.

Fluid as a critical biomarker in neovascular age-related macular degeneration management: literature review and consensus recommendations

Current guidelines on the management of patients with neovascular age-related macular degeneration (nAMD) lack clear recommendations on the interpretation of fluid as seen on optical coherence tomography (OCT) imaging and the incorporation of this information into an ongoing disease treatment strategy. Our objective was to review current guidelines and scientific evidence on the role of fluid as a biomarker in the management of nAMD, and develop a clinically oriented, practical algorithm for diagnosis and management based on a consensus of expert European retinal specialists. PubMed was searched for articles published since 2006 relating to the role of fluid in nAMD. A total of 654 publications were screened for relevance and 66 publications were included for review. Of these, 14 were treatment guidelines, consensus statements and systematic reviews or meta-analyses, in which OCT was consistently recommended as an important tool in the initial diagnosis and ongoing management of nAMD. However, few guidelines distinguished between types of fluid when providing recommendations. A total of 52 publications reported primary evidence from clinical trials, studies, and chart reviews. Observations from these were sometimes inconsistent, but trends were observed with regard to features reported as being predictive of visual outcomes. Based on these findings, diagnostic recommendations and a treatment algorithm based on a treat-and-extend (T&E) regimen were developed. These provide guidance on the diagnosis of nAMD as well as a simple treatment pathway based on the T&E regimen, with treatment decisions made according to the observations of fluid as a critical biomarker for disease activity.

Strongest Correlation Between Contrast Sensitivity and Morphological Characteristics in Bilateral nAMD

In patients with neovascular age-related macular degeneration (nAMD) there is often an inconsistency between their subjective visual impairment and a still relatively preserved standard Early Treatment of Diabetic Retinopathy Study (ETDRS) best corrected visual acuity. Therefore, in order to better capture the specific functional defects in nAMD, other tests need to be evaluated. In a previous study, we reported contrast sensitivity of the better eye to best correlate with near distance and distance vision related quality of life in patients with bilateral nAMD. Here, we evaluated Pelli-Robson contrast sensitivity, ETDRS visual acuity, low luminance visual acuity and Radner maximum reading speed and correlated them with several morphologic parameters as measured on fundus autofluorescence imaging, optical coherence tomography and optical tomography angiography in 54 patients. A multiple regression analysis was performed which correlated each visual function parameter with the anatomic features. The results showed the strongest correlations between the total area of macular geographic atrophy as well as the percentage of geographic atrophy in the central 1 mm and contrast sensitivity. Further, the regression model selected the total area of macular geographic atrophy, the photoreceptor inner and outer segments interface disruption score, the presence of subretinal fibrosis in the central 1 mm and the central retinal thickness as the variables that explained 71% of the variation in contrast sensitivity when including all eyes. Hence, our results suggest that among the evaluated measures of vision, contrast sensitivity is best correlated with the morphologic impairment in bilateral nAMD. Thus, contrast sensitivity may complement ETDRS visual acuity in clinical trials and serve as a standard diagnostic tool in clinical practice.

Spectral-Domain Optical Coherence Tomography Analysis of Fibrotic Lesions in Neovascular Age-Related Macular Degeneration

PURPOSE

To describe the spectral-domain optical coherence tomography (OCT) features of fibrotic lesions associated with neovascular age-related macular degeneration (nAMD) and to outline the progression pathways from initial macular choroidal neovascular lesions (CNVs) to fibrosis.

METHODS

Patients with nAMD were retrospectively included when macular subretinal fibrosis was present. Fibrosis was categorized using spectral-domain OCT with respect to retinal pigment epithelium (RPE) in 836 spectral-domain OCT slices from 44 eyes of 39 patients. In addition, in 47 distinct eyes, 4181 spectral-domain OCT slices were retrospectively reviewed to longitudinally assess progression from the initial lesion to the final fibrosis.

RESULTS

Cross-sectional analysis classified fibrosis on spectral-domain OCT slices, as type A if located underneath the RPE, as type B if located above the RPE, and as type C if the remaining RPE was undistinguishable. The longitudinal analysis series revealed 3 progression pathways from the original CNV: 1) progression to type A, followed by RPE erosion and subretinal hyperreflective material, then type B and type C fibroglial lesion (FGL; 17/47 eyes); 2) progression to type B then type C FGL (17/47 eyes); and 3) persistence of type A with development of a flat, fibroatrophic lesion (13/47 eyes). Subretinal hyperreflective material, macular hemorrhage, or RPE tear occurred in 14 of 47, 13 of 47, and 10 of 47 eyes, respectively.

CONCLUSION

This spectral-domain OCT analysis identified various patterns of macular fibrosis in eyes with nAMD. Three pathways of progression to fibrosis were described including the well-established pathway of type 2 CNV progression to FGL and the progression of type 1 fibrovascular CNV to FGL or fibroatrophic lesion.

Bevacizumab versus ranibizumab for neovascular age-related macular degeneration: a Meta-analysis

AIM

To systematically compare the efficacy and safety of off-label bevacizumab versus licensed ranibizumab intravitreal injections as well as monthly regimen versus pro re nata [PRN (as needed)] regimen in the treatment of neovascular age-related macular degeneration (nAMD).

METHODS

Relevant publications were identified through automatically retrieve of database and manually retrieving. The methodological quality of studies included was assessed using the Jadad score and the risk-of-bias assessment. The efficacy estimates were measured by the weight mean difference (WMD) for the improvement of best-corrected visual acuity (BCVA) and central retinal thickness (CRT) reduction. The safety estimates were measured by odds ratios (OR) for adverse events rates. Statistical analysis was conducted by Revman 5.2.7.

RESULTS

Seven studies were included in the Meta-analysis. There were no statistically significant differences between bevacizumab and ranibizumab in BCVA at 1 and 2y (P=0.37, P=0.18, respectively), However, both drugs has better BCVA given monthly than given as needed at 1 and 2y (P<0.05). The results demonstrated the mean decrease in CRT was less in bevacizumab group than ranibizumab group at 1y (P<0.05), while the difference was not significant at 2y (P=0.24). Treatment monthly gained much more decrease in CRT at 1 and 2y (P<0.005). There were no differences between drugs in the rates of death, arterial thrombotic events and venous thrombotic events (P=0.41, P=0.55, P=0.10, respectively), while the rates of medical dictionary for regulatory activities (MedDAR) system organ class events and ≥1 systemic serious adverse events were higher in bevacizumab group than ranibizumab group (P<0.05). But the incidences of death, arterial thrombotic events, venous thrombotic events, MedDAR system organ class events as well as ≥1 systemic serious adverse events were not statistically different between both treatment regimens of monthly and as needed (P=0.14, P=0.76, P=0.73, P=0.12, P=0.11, respectively).

CONCLUSION

Bevacizumab was equivalent to ranibizumab for BCVA, however bevacizumab tended to gain less decrease in CRT and had higher rates of serious adverse events. Compared with treatment as needed, treatment monthly showed superior efficacy in BCVA improvement and CRT reduction, while the rates of adverse events were similar in the two dosing regimens.

Structures affecting recovery of macular function in patients with age-related macular degeneration after intravitreal ranibizumab

PURPOSE

To determine the retinal structures affecting the recovery of macular function in patients with exudative age-related macular degeneration (AMD) treated with intravitreal ranibizumab (IVR).

METHOD

Thirty eyes of 30 patients with exudative AMD who were treated with IVR at monthly intervals for 3 months were studied. Focal macular electroretinograms (fmERGs) and spectral-domain optical coherence tomography (SD-OCT) were performed before and 3 months after beginning the IVR injections. The fmERGs were elicited by a 15° white stimulus spot centered on the fovea. The thickness of different retinal layers, presence of a serous retinal detachment (SRD), and presence of a pigment epithelial detachment (PED) at the fovea was determined in the SD-OCT images. Measurements were made of the inner, middle, and outer layers of the retina and also of the SRD and PED in the horizontal and vertical meridians at 1.2 mm from the fovea (parafoveal regions). The significance of the correlations between these structural parameters and the a-wave amplitude of the fmERG was determined.

RESULTS

There was no significant correlation between the structural parameters of the fovea and the a-wave amplitude. In the parafoveal regions, the thickness of the outer retinal layer was significantly correlated with an increase of the a-wave amplitude (R = 0.56, P = 0.001). In addition, the SRD thickness was negatively and significantly correlated with the a-wave amplitude (R = -0.54, P = 0.002). The change in the parafoveal SRD thickness after IVRs was the only independent determinant of recovery of the a-wave amplitude after the treatments (P < 0.05).

CONCLUSIONS

The macular function measured by the fmERGs was determined by the parafoveal outer layer and SRD thickness in patients with exudative AMD. Of these, changes in the SRD thickness by IVRs most strongly affected the recovery of macular function.

Risk of scar in the comparison of age-related macular degeneration treatments trials

OBJECTIVE

To describe risk factors for scar in eyes treated with ranibizumab or bevacizumab for neovascular age-related macular degeneration (AMD).

DESIGN

Prospective cohort study within a randomized clinical trial.

PARTICIPANTS

Patients with no scar on color fundus photography (CFP) or fluorescein angiography (FA) at enrollment in the Comparison of Age-related Macular Degeneration Treatments Trials (CATT).

METHODS

Eyes were assigned to ranibizumab or bevacizumab treatment and to 1 of 3 dosing regimens for 2 years. Masked readers assessed CFP and FA. Baseline demographic characteristics, visual acuity, morphologic features on photography and optical coherence tomography (OCT), and genotypes associated with AMD risk were evaluated as risk factors using adjusted hazard ratios (aHRs) and associated 95% confidence intervals (CIs). Scars were classified as fibrotic with well-demarcated elevated mounds of yellowish white tissue or nonfibrotic with discrete flat areas of hyperpigmentation with varying amounts of central depigmentation.

MAIN OUTCOME MEASURES

Scar formation.

RESULTS

Scar developed in 480 of 1059 eyes (45.3%) by 2 years. Baseline characteristics associated with greater risk of scarring were predominantly classic choroidal neovascularization (CNV) (aHR, 3.1; CI, 2.4-3.9) versus occult CNV, blocked fluorescence (aHR, 1.4; CI, 1.1-1.8), foveal retinal thickness >212 μm (aHR, 2.4; CI, 1.7-3.6) versus <120 μm, foveal subretinal tissue complex thickness >275 μm (aHR, 2.4; CI, 1.7-3.6) versus ≤75 μm, foveal subretinal fluid (aHR, 1.5; CI, 1.1-2.0) versus no subretinal fluid, and subretinal hyperreflective material (SHRM) (aHR, 1.7; CI, 1.3-2.3) versus no SHRM. Eyes with elevation of the retinal pigment epithelium had lower risk (aHR, 0.6; CI, 0.5-0.8) versus no elevation. Drug, dosing regimen, and genotype had no statistically significant association with scarring. Fibrotic scars developed in 24.7% of eyes, and nonfibrotic scars developed in 20.6% of eyes. Baseline risk factors for the scar types were similar except that eyes with larger lesion size or visual acuity <20/40 were more likely to develop fibrotic scars.

CONCLUSIONS

Approximately half of eyes enrolled in CATT developed scar by 2 years. Eyes with classic neovascularization, a thicker retina, and more fluid or material under the foveal center of the retina are more likely to develop scar.

Current smoking is associated with a poor visual acuity improvement after intravitreal ranibizumab therapy in patients with exudative age-related macular degeneration

In this study, the risk factors that may influence visual improvement after intravitreal ranibizumab (IVR) treatment for exudative age-related macular degeneration (AMD) were examined. From 2008 to 2012, 420 patients (448 eyes) with exudative AMD were prospectively registered at Seoul National University Hospital. From this group of patients, 125 eyes were included in this study. All patients were treated with 3 consecutive IVR injections. The visual acuity (VA) was evaluated at baseline and 1 month after the third ranibizumab injection. To evaluate the risk factors associated with VA improvement after IVR, patient demographic data and systemic risk factors were analyzed. Patients were divided into a poor VA improvement group and a good VA improvement group, with reference to the median visual improvement in all eyes. Among 125 eyes, 66 eyes (52.8%) were included in the responder group and 59 eyes (47.2%) in the non-responder group. The median VA improvement after 3 monthly ranibizumab injections was -0.05 logMAR. Multivariate analyses revealed that current smoking (adjusted OR, 7.540; 95% CI, 1.732-32.823) was independently associated with poor VA improvement after IVR treatment for exudative AMD. In conclusion, cigarette smoking is an independent risk factor for lower VA gains with IVR treatment for exudative AMD.

Predictors of visual outcome in eyes with choroidal neovascularization secondary to age related macular degeneration treated with intravitreal bevacizumab monotherapy

AIM

To evaluate the predictors of visual improvement in eyes with naive choroidal neovascularization secondary to age-related macular degeneration (CNV -AMD) treated with intravitreal bevacizumab (IVB) monotherapy.

METHODS

Fifty eyes with naive CNV- AMD with pretreatment best-corrected visual acuity (BCVA) better than 20/200 and treated with IVB monotherapy were evaluated. Several variables including age, sex, pre-treatment BCVA, CNV type and lesion size on fluorescein angiogram as well as SD-OCT parameters including pre-treatment central macular thickness (CMT), inner-segment/outer-segment (IS/OS) junction integrity, and external limiting membrane (ELM) integrity were analyzed to predict visual outcome.

RESULTS

On univariate regression, pretreatment ELM damage was associated with less visual improvement after treatment (P=0.0145). However, ELM damage predicted only 10% of the visual outcome. On multivariate regression, pretreatment BCVA, IS/OS junction, and ELM integrity on SD-OCT were the significant predictors for the treatment effect and together predicted 37% of visual improvement.

CONCLUSION

Pretreatment BCVA, ELM and IS/OS junction integrity on SD-OCT are of significant value in predicting the visual improvement in naive wet AMD patients treated with IVB monotherapy.

Pharmaceutical composition for treating macular degeneration (WO2012079419)

A pharmaceutical composition composed of several traditional Chinese medicines is claimed to treat age-related macular degeneration (AMD). This represents a novel and alternative therapeutic solution for wet AMD, with the potential advantage of treating both the symptoms and the underlying causes of this devastating degenerative retinal disease.

Recovery of photoreceptor outer segments after anti-VEGF therapy for age-related macular degeneration

PURPOSE

To evaluate whether the status of the external limiting membrane (ELM) or inner segment/outer segment junction (IS/OS) improves after intravitreal injection of ranibizumab for age-related macular degeneration (AMD). We also evaluated whether the pre-operative values of these parameters are associated with the visual prognosis.

METHODS

This was a hospital-based, cross-sectional study. Seventy-six eyes of 76 treatment-naive AMD patients who received three monthly intravitreal injections of ranibizumab followed for more than 6 months with additional as-needed injections were investigated. Spectral domain OCT was used to evaluate the length of ELM, IS/OS, and foveal thickness pre- and post-operatively. Changes of ELM and IS/OS length were evaluated postoperatively. Correlation coefficients between pre-operative parameters and post-operative visual acuity were also analyzed.

RESULTS

Significant changes were noted in mean logMAR (0.66 to 0.53), foveal thickness (231.1 to 151.1 μm), and IS/OS length (514.9 to 832.3 μm) after the treatment. ELM length did not improve significantly (1,312.4 to 1,376.7 μm). Restoration of IS/OS occurred where ELM is retained. Although pre-operative ELM length, IS/OS length, and foveal thickness showed correlation with post-operative logMAR (R = -0.51, -0.39, and 0.46, respectively), the most powerful predictive factor for visual prognosis was pre-operative logMAR (R = 0.77, p < 0.001).

CONCLUSIONS

IS/OS status improves in response to anti-VEGF therapy but ELM seems to have less plasticity. The status of IS/OS and ELM can be used as prognostic factors but the predictive power is inferior to that of baseline visual acuity.

Intravitreal bevacizumab (Avastin) for age-related macular degeneration: a critical analysis of literature

PURPOSE

The current medical environment demands that quality health care is delivered at an affordable cost through the use of objective, unbiased clinical data. This study was undertaken to review the current literature on bevacizumab for age-related macular degeneration and its value in determining best clinical practice.

METHODS

Randomised controlled trials (RCTs) and observational studies that met the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria were identified from the current literature for further analysis. Data concerning treatment dosing regimens, response to treatment, complications, and factors influencing outcome and safety were extracted and compiled into a database.

RESULTS

As of January 2009, there were 5 RCTs that compared the outcomes of bevacizumab to other treatment options and 50 studies that met the STROBE criteria with similar visual and anatomical outcomes between RCTs and observational studies. Although the doses and dosing frequencies varied between the studies, the mean gain in vision at 3 months was +7.76+/-5.4 ETDRS letters (range +2 to +14.4); an effect that was maintained at 6 months in studies with longer follow-up. Predominantly classic lesions were the most responsive of all lesion subtypes. The complication profiles/rates were similar to those reported with other anti-vascular endothelial agents.

CONCLUSIONS

There is sufficient scientific and statistical evidence to advocate the effective use of OCT-guided administration of intravitreal bevacizumab for neovascular AMD. This is reflected in our study outcome measures that are comparable to findings published from recent well-conducted RCTs on intravitreal ranibizumab at the same time point.