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Volume 8, Number 12 |
December 2012 |
WELCOME to Review
of Ophthalmology's Retina
Online e-newsletter. Each month, Medical Editor Philip Rosenfeld,
MD, PhD, and our editors provide you with this timely and easily
accessible report to keep you up to date on important information
affecting the care of patients with vitreoretinal disease.
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Macular Epiretinal Brachytherapy and Treated AMD
This prospective, multicenter, interventional, noncontrolled clinical trial reported the optical coherence
tomography (OCT) and fundus fluorescein angiography (FFA) results of the Macular Epiretinal Brachytherapy in
Treated Age-Related Macular Degeneration study.
It included 53 eyes of 53 participants with chronic, active neovascular age-related macular degeneration (AMD)
requiring frequent anti-vascular endothelial growth factor (VEGF) retreatment.
Participants underwent pars plana vitrectomy with a single 24-gray dose of epimacular brachytherapy (EMB) delivered
with an intraocular, handheld cannula containing a strontium 90/yttrium 90 source positioned over the active
lesion. Participants were retreated with ranibizumab administered monthly as needed, using predefined
retreatment criteria. They also underwent FFA at baseline, month one and month 12. Patients underwent OCT at
baseline and then monthly for 12 months. The FFA and OCT images were evaluated by independent, central
reading facilities. Main outcome measures were changes in OCT centerpoint thickness and angiographic lesion
size 12 months following EMB.
It was reported that mean centerpoint thickness increased by 50 µm, from 186 to 236 µm (p=0.292),
but that 70% of participants had an increase of less than the mean, with a median increase of only 1.8 µm.
The FFA total lesion size increased slightly by 0.79 mm², from 14.69 to 15.48 mm² (p=0.710).
It was also noted that total choroidal neovascularization (CNV) area increased by 1.17 mm², from 12.94 to
14.12 mm² (p=0.556). The classic CNV area decreased substantially by 3.70 mm², from 3.90 to
0.20 mm² (p<0.01). Predominantly classic lesions showed the greatest response, with mean Early
Treatment Diabetic Retinopathy Study visual acuity improving by 1.5 letters (versus –4.0 for all
participants combined); mean centerpoint thickness decreased by 43 µm (p=0.875). Furthermore,
the angiographic and OCT response did not correlate with lesion size at baseline.
In chronic, active, neovascular AMD, EMB is associated with nonsignificant changes in centerpoint thickness
and FFA total lesion size over 12 months.
Source: Petrarca R, Dugel PU, Nau J, et al. Macular epiretinal brachytherapy in treated age-related
macular degeneration (MERITAGE Study). Ophthalmology. 2012;Nov 23. [Epub ahead of print].
DOI: 10.1016/j.ophtha.2012.07.091.
Benefit of Four Years of Intravitreal Ranibizumab Treatment
for Neovascular AMD
Investigators in the United Kingdom sought to analyze the benefit of intravitreal ranibizumab over
four years for patients with neovascular age-related macular degeneration (AMD).
They performed a retrospective case note review of all patients who started treatment between August 2007 and
September 2009 in their unit, minimum follow-up two years, maximum four years. The main outcome measures were:
numbers of patients with different levels of vision; changes in visual acuity; number of treatments; and
numbers remaining under follow-up.
According to the investigators, 1,086 eyes of 1,017 patients received treatment. They noted that numbers of
patients remaining under follow-up were 892/1,017 (87.71%) at 12 months, 730/1,017 (71.78%) at 24
months, 468/730 (64.11%) at 36 months and 110/217 (50.69%) at 48 months. The main reasons for patients
no longer being under follow-up were the consequences of old age or transfer of care. Additionally, 50% of
patients had 6/18 or better over four years. The study investigators also reported that patients received on
average 5.79 ± 2.53, 9.15 ± 3.79, 11.22 ± 4.92 and 13.7 ± 7.84 injections by 12, 24, 36 and
48 months, respectively.
They suggest that the numbers of patients with a particular level of vision may best reflect the actual benefit
of AMD treatment provided by a service. Long-term follow-up is required as only 72/730 (10%) had been discharged
at 36 months, half of whom had good vision of greater than 60 letters. Moreover, 83% and 65% of patients
needed treatment in the third and fourth year. Follow-up may be for the rest of the patient’s life or at some point
they may no longer be well enough to attend.
Source: Pushpoth S, Sykakis E, Merchant K, et al. Measuring the benefit of four years of
intravitreal ranibizumab treatment for neovascular age-related macular degeneration.
Br J Ophthalmol. 2012;96(12):1469–1473.
Performance of Intravitreal Aflibercept (VEGF Trap-Eye) in Wet AMD
The authors of the following two similarly designed, Phase III studies (VEGF Trap-Eye: Investigation of
Efficacy and Safety in Wet AMD [VIEW 1, VIEW 2]) of neovascular age-related macular degeneration (AMD)
compared monthly and every-two-month dosing of intravitreal aflibercept injection (VEGF Trap-Eye) with
monthly ranibizumab.
Both studies included 2,419 patients with active, subfoveal, choroidal neovascularization (CNV) lesions
(or juxtafoveal lesions with leakage affecting the fovea) secondary to AMD. They were randomized to
intravitreal aflibercept 0.5 mg monthly (0.5q4), 2 mg monthly (2q4), 2 mg every two months after three initial
monthly doses (2q8), or ranibizumab 0.5 mg monthly (Rq4). The primary endpoint was noninferiority (margin of 10%)
of the aflibercept regimens to ranibizumab in the proportion of patients maintaining vision at week 52
(losing <15 letters on Early Treatment Diabetic Retinopathy Study [ETDRS] chart). Other key end points
included change in best-corrected visual acuity (BCVA) and anatomic measures.
All aflibercept groups were noninferior and clinically equivalent to monthly ranibizumab for the primary endpoint
(the 2q4, 0.5q4 and 2q8 regimens were 95.1%, 95.9% and 95.1%, respectively, for VIEW 1, and 95.6%,
96.3% and 95.6%, respectively, for VIEW 2, whereas monthly ranibizumab was 94.4% in both studies).
In a prespecified integrated analysis of the two studies, all aflibercept regimens were within 0.5 letters of
the reference ranibizumab for mean change in BCVA; all aflibercept regimens also produced similar improvements
in anatomic measures. Ocular and systemic adverse events were similar across treatment groups.
The authors found that intravitreal aflibercept dosed monthly or every two months after three initial monthly
doses produced efficacy and safety outcomes similar to monthly ranibizumab. These studies demonstrate that
aflibercept is an effective treatment for AMD, with the every-two-month regimen offering the potential to reduce
the risk from monthly intravitreal injections and the burden of monthly monitoring.
Source: Heier JS, Brown DM, Chong V, et al; VIEW 1 and VIEW 2 Study Groups. Intravitreal aflibercept
(VEGF Trap-Eye) in wet age-related macular degeneration. Ophthalmology. 2012;119(12):2537–2548.
CNV Complicating GA in AMD
French researchers investigators examined the morphological and functional outcomes following
intravitreal ranibizumab injections for choroidal neovascularization (CNV) complicating geographic atrophy (GA).
In a retrospective, interventional, consecutive case series, they reviewed the charts of all consecutive patients
with GA due to age-related macular degeneration (AMD) who received intravitreal ranibizumab injections for
the development of CNV at least 24 months earlier.
The researchers included 21 treatment-naive eyes of 21 consecutive patients (four men, 17 women, mean age
86.9 ± 1.6 years). They noted that in 95.2% of eyes, a type 2 CNV was present, extrafoveal in
42.8% of cases. After a mean of 5.0 ± 0.87 (range 1–20) intravitreal ranibizumab
injections, best-corrected visual acuity (BCVA) significantly worsened at the 24-month follow-up visit
(0.73 ± 0.05 vs. 0.88 ± 0.08 logMAR, respectively; p=0.01). A significant reduction of
intraretinal cystic lesions, subretinal fluid and pigment epithelium detachment (p<0.001) and a
significant increase of GA area (p=0.003) were present at last visit, the study researchers reported.
They concluded that ranibizumab treatment of GA-associated CNVs provides no BCVA improvement at 24 months
follow-up despite an anatomic response of CNV. Low effectiveness of ranibizumab in these cases is likely due
to GA progression.
Source: Querques G, Massamba N, Coscas F, et al. Choroidal neovascularization complicating
geographic atrophy in age-related macular degeneration. Br J Ophthalmol. 2012;96(12):1479–1483.
Results of PDT Therapy for PCV After Five Years
The following Korean retrospective study evaluated the five-year efficacy of photodynamic therapy (PDT)
in patients with polypoidal choroidal vasculopathy (PCV).
Forty-two eyes of 36 patients with PCV followed up for at least 60 months after PDT were reviewed. All eyes
were primarily treated with PDT. The main outcome measure was best-corrected visual acuity (BCVA; logMAR [logarithm
of minimal angle of resolution]) at baseline and at each follow-up visit. The eyes were also classified into
three groups: improved (improvement ≥0.3 logMAR), decreased (deterioration ≥0.3 logMAR) and stable.
During the mean follow-up duration, 73.64 ± 13.47 months, the mean number of PDT was 2.21 ± 1.62
treatments. Recurrence was noted in 33 eyes (78.6%) during follow-up. The mean baseline BCVA was 0.78 ±
0.48 logMAR (20/120 Snellen equivalent), and the final BCVA at 60 months was 0.67 ± 0.52 logMAR (20/93
Snellen equivalent) (p=.050, paired t test). On the final evaluation at 60 months, the mean BCVA
was improved in 14 eyes (33.3%), stable in 23 eyes (54.7%) and decreased in five eyes (11.9%).
In conclusion, at 60 months following initial PDT, 88.1% of PCV patients showed stable or improved BCVA after
PDT. Despite a high recurrence rate, PDT remained effective for five years, and represents a good therapeutic
approach to PCV.
Source: Kang HM, Kim YM, Koh HJ. Five-year follow-up results of photodynamic therapy for
polypoidal choroidal vasculopathy. Am J Ophthalmol. 2012;Dec 4 [Epub ahead of print].
Link Between CSCR and Risk of Ischemic Stroke
Central serous chorioretinopathy (CSCR) is a common maculopathy that features choroidal circulatory
disturbance. Scientists in Taiwan aimed to explore the relationship between CSCR and the future development
of ischemic stroke in this population-based cohort study.
Data were obtained from Taiwan's national health insurance research database. From 2000 to 2007, 1,814 patients
with newly diagnosed CSCR were eligible for inclusion in the study cohort. Using stratified random sampling,
the scientists selected 9,648 enrollees matched with the study subjects in terms of sex, age, monthly
income, geographical location and time of enrollment as the control group. They also assessed stroke-free
survival analysis using a Kaplan–Meier method. Additionally, they performed Cox proportional hazard regressions
to calculate the HR of ischemic stroke for the two groups after adjusting for possible confounding variables.
Of the sampled patients, 45 (2.5%) from the CSCR cohort and 157 (1.6%) from the control group developed
ischemic stroke during a mean follow-up period of 3.9 ± 2.2 years. According to the study scientists, CSCR
patients had a significantly higher incidence of ischemic stroke than those without a diagnosis of CSCR
(p=0.003). After adjusting for age, sex and chronic comorbidities at baseline, they found CSCR patients
to have a 1.56-fold (95% CI 1.11 to 2.18, p=0.010) greater risk of a subsequent ischemic stroke
than the matched controls.
CSCR is an independent indicator for the increased risk of subsequent ischemic stroke development.
Source: Tsai DC, Huang CC, Chen SJ, et al. Central serous chorioretinopathy and risk of ischemic
stroke: a population-based cohort study. Br J Ophthalmol. 2012;96(12):1484–1488.
Risk Factors Associated with CRVO
To identify risk factors associated with central retinal vein occlusion (CRVO) among a diverse group of
patients throughout the United States, investigators performed the following longitudinal cohort study.
Participants included all beneficiaries aged ≥55 years who were continuously enrolled in a managed-care network
for at least two years and who had two or more visits to an eye-care provider from 2001 to 2009.
They used insurance billing codes to identify individuals with a newly diagnosed CRVO and performed multivariable
Cox regression to determine the factors associated with CRVO development. Adjusted hazard ratios (HRs) with
95% confidence intervals (CIs) of being diagnosed with CRVO were the main outcome measures.
The investigators reported that of the 494,165 enrollees who met the study inclusion criteria, 1,302 (0.26%)
were diagnosed with CRVO over 5.4 (±1.8) years. They noted that after adjustment for known confounders, blacks
had a 58% increased risk of CRVO compared with whites (HR, 1.58; 95% CI, 1.25–1.99), and women had a
25% decreased risk of CRVO compared with men (HR, 0.75; 95% CI, 0.66–0.85). Moreover, they found that
a diagnosis of stroke increased the hazard of CRVO by 44% (HR, 1.44; 95% CI, 1.23–1.68),
and hypercoagulable state was associated with a 145% increased CRVO risk (HR, 2.45; 95% CI,
1.40–4.28). Individuals with end-organ damage from hypertension (HTN) or diabetes mellitus (DM) had a
92% (HR, 1.92; 95% CI, 1.52–2.42) and 53% (HR, 1.53; 95% CI, 1.28–1.84) increased
risk of CRVO, respectively, relative to those without these conditions.
This study confirms that HTN and vascular diseases are important risk factors for CRVO. The study investigators
also identify black race as being associated with CRVO, which was not well appreciated previously. Furthermore,
they show that compared with patients without DM, individuals with end-organ damage from DM have a heightened risk
of CRVO, whereas those with uncomplicated DM are not at increased risk of CRVO. This finding may provide a
potential explanation for the conflicting reports in the literature on the association between CRVO and DM.
Information from analyses such as this can be used to create a risk calculator to identify possible individuals
at greatest risk for CRVO.
Source: Stem MX, Talwar N, Comer GM, Stein JD. A longitudinal analysis of risk factors associated
with central retinal vein occlusion. Ophthalmology. 2012; Nov 21. [Epub ahead of print].
DOI: 10.1016/j.ophtha.2012.07.080.
Electroretinographic Parameters and Inflammatory Factors in
BRVO with ME
Branch retinal vein occlusion (BRVO) leads to retinal ischemia, which then induces upregulation of various
inflammatory factors, including vascular endothelial growth factor (VEGF). The aim of this Japanese study was
to determine whether there was a correlation between inflammatory factors and components of the electroretinogram
(ERG) in patients with BRVO.
In 19 BRVO patients with macular edema (ME), vitreous fluid samples were obtained during vitreoretinal surgery
to measure the levels of four inflammatory factors (VEGF, soluble intercellular adhesion molecule-1
[sICAM-1], interleukin [IL]-6 and monocyte chemotactic protein [MCP]-1). The amplitude and implicit time of the
a-wave cone, b-wave cone, and 30 Hz flicker were calculated automatically from the ERG. Correlations between
the different components of the ERG and the four inflammatory factors were investigated.
Vitreous fluid levels of two factors (IL-6 and MCP-1) were significantly correlated with the implicit time of the
cone b-wave (p=0.035 and p=0.016, respectively). It was also noted that vitreous fluid levels of all
four factors (VEGF, sICAM-1, IL-6 and MCP-1) were significantly correlated with the implicit time of 30 Hz flicker
(p=0.047, p=0.031, p=0.002 and p=0.009, respectively). Vitreous fluid levels of
VEGF, sICAM-1, IL-6, and MCP-1 were significantly higher in patients with an implicit time ≥36 ms than with an
implicit time <36 ms (p=0.042, p=0.048, p=0.003 and p=0.024, respectively).
These findings suggest that the implicit times of the cone b-wave and 30 Hz flicker can be used to detect BRVO
patients with ME who have a high risk of ischemia.
Source: Noma H, Funatsu H, Mimura T. Association of electroretinographic parameters and
inflammatory factors in branch retinal vein occlusion with macular edema. Br J Ophthalmol. 2012;
96(12):1489–1493.
Relationship Between the p53 Codon 72 Polymorphism (rs1042522)
and Proliferative Vitreoretinopathy
The following case-controlled gene association study was conducted as a component of the Retina 4 Project
(a European multicenter study). In it, the authors compared the distribution of a p53 gene polymorphism among
European subjects undergoing primary retinal detachment (RD) surgery in relation to the development of
proliferative vitreoretinopathy (PVR).
They included 550 DNA samples, 134 with PVR secondary to primary RD and 416 with RD without PVR. The authors
analyzed the p53 codon 72 polymorphism (rs1042522) using allele-specific primer polymerase chain reaction.
They analyzed proportions of genotypes and the proline (Pro-P) homozygote groups between subsamples from
different countries in two phases. In the first, they analyzed subsamples from Spain and Portugal. After
significant results were found, samples from the United Kingdom and the Netherlands were analyzed (second phase).
The study authors compared genotypic and allelic frequencies between cases and controls in the global sample.
They noted that main outcome measures were single significant associations with PVR.
They observed significant difference (p<0.05, Fisher exact test) regarding the p53 genotype frequencies
at codon 72 between the PVR cases and the non-PVR controls in Spain and Portugal (phase I), but not in the
United Kingdom or the Netherlands (phase II). Analysis of Pro homozygote carriers between cases and controls
revealed differences in Spain (29.01–42.18 and 2.29–10.20, respectively), Portugal (10.49–29.50
and 1.35–8.89, respectively) and the Netherlands (16.49–31.70 and 4.51–15.09, respectively),
but no differences in the United Kingdom (7.68–18.1 and 4.85–13.94, respectively). According to the
authors, the odds ratio of Pro carriers from Spain and Portugal together was 8.12 (95% confidence interval
[CI], 3.72–17.69; p<0.05), whereas the odds ratio of Pro carriers from the United Kingdom and
the Netherlands was 2.12 (95% CI, 0.96–4.68; p=0.07). All control samples were in
Hardy-Weinberg equilibrium. Considering the entire sample, significant differences were found in genotype
frequencies between cases (RR, 30.59%; RP, 43.28%; PP, 26.11% [R=Arg; P=Pro]) and controls
(RR, 39.66%; RP, 52.64%; PP, 7.69%) and in Pro homozygote carriers between controls (Pro homozygote
95% CI, 18.67–33.52) and cases (Pro homozygote 95% CI, 5.1–10.2).
Results indicate that the Pro variant of p53 codon 72 polymorphism is associated with a higher risk of PVR
developing after a primary RD. Further studies are necessary to understand the role of this polymorphism in
the development of PVR.
Source: Pastor-Idoate S, Rodriguez-Hernández I, Rojas J, et al; Genetics on PVR Study Group.
The p53 codon 72 polymorphism (rs1042522) is associated with proliferative vitreoretinopathy:
the Retina 4 Project. Ophthalmology. 2012;Dec 3. [Epub ahead of print]. DOI: 10.1016/j.ophtha.2012.08.019.
Pascal TargETEd Retinal Versus Variable Fluence PANretinal
20 ms laser in DR
To investigate the short-term effects of high-density 20-ms laser on macular thickness using Pascal-targeted
retinal photocoagulation (TRP) and reduced fluence/minimally traumatic panretinal photocoagulation (MT-PRP)
compared to standard-intensity PRP (SI-PRP) in proliferative diabetic retinopathy (PDR), researchers conducted
this prospective, randomized clinical trial.
They treated treatment-naïve PDR with single-session 20-ms Pascal 2,500 burns photocoagulation randomized
to one of three treatment arms (TRP:MT-PRP:SI-PRP). Primary outcome measure was change in central retinal
thickness (CRT) on OCT and secondary outcomes at four and 12 weeks post-laser included: OCT peripapillary nerve
fiber layer (NFL) thickness, PDR disease regression on Optos angiography, SITA-Std visual fields (VF) and visual
acuity (VA).
The researchers studied 30 eyes of 24 patients, 10 eyes/arm. At 12 weeks, they noted significant reductions in
CRT after TRP (9.6 µm; 95% CI, 1.84 to 17.36; p=0.021) and MT-PRP (17.1 µm; 95% CI, 11
to 23.2; p=0.001), versus SI-PRP (+5.9 µm; 95% CI, –6.75 to 18.55; p=0.32).
PDR regression was similar between groups (TRP 70%; MT-PRP 70%; SI-PRP 90%; Κ=0.76) and no
significant changes in VA and NFL thickness developed between groups. Additionally, the VF mean deviation
scores increased significantly in all groups at 12 weeks ([TRP, +0.70dB; 95% CI, 0.07 to 1.48;
p=0.07], [MT-PRP, +0.63dB; 95% CI, 0.12 to 1.15; p=0.02], [SI-PRP, +1.0dB; 95% CI, 0.19 to
1.74; p=0.02]). There were no laser-related ocular complications.
This pilot study reports that high-density 20-ms Pascal TRP and MT-PRP using 2,500 burns did not produce
increased macular thickness or any ocular adverse events during the short-term.
Source: Muqit MM, Young LB, McKenzie R, et al. Pilot randomized clinical trial of Pascal TargETEd
Retinal versus variable fluence PANretinal 20 ms laser in diabetic retinopathy: PETER PAN study.
Br J Ophthalmol. 2012;Nov 24. [Epub ahead of print]. DOI: 10.1136/bjophthalmol-2012-302189.
Topographical Distribution of Retinal and Optic Disc
Neovascularization in Early Stages of PDR
In Norway, investigators analyzed the topography of proliferative diabetic retinopathy (PDR) and visualized
the distribution of neovascularization of the optic disc (NVD) and elsewhere in the retina (NVE).
They included 174 eyes of 106 patients with early PDR and converted data on the size and location of 391 NVE and
73 NVD into a database of two-dimensional retinal and optic disc charts. They also plotted geometric centers of
the neovascular lesions into corresponding areas of the charts, and they visualized topographical distributions of
the NVE and NVD by merging the charts and displaying the number of overlapping lesions on color-coded contour maps.
According to the investigators, a total of 141 (36%) NVE were located in the temporal and 250 (64%) in the
nasal hemisphere (p<0.0001). They noted that the distribution of the NVD in the temporal and nasal half
of the optic disc was 46 (63%) and 27 (37%), respectively (p=0.03). They also found that NVE in
type 1 diabetes were located significantly farther from the fovea and optic disc and were more numerous and larger
than in type 2 diabetes. Furthermore, the number and diameter of the NVE were also significantly higher when the
time from the last examination prior to the appearance of PDR exceeded 12 months.
The majority of NVE are located inferonasal to the optic disc and along the superior vascular arcades, while NVD
have a predilection for the upper temporal disc rim. More extensive PDR is found in patients with type 1 diabetes,
and those with examination intervals longer than one year.
Source: Jansson RW, Froystein T, Krohn J. Topographical distribution of retinal and optic
disc neovascularization in early stages of proliferative diabetic retinopathy. Invest Ophthalmol
Vis Sci. 2012; Nov 20. [Epub ahead of print]. DOI: 10.1167/iovs.12-10918.
ELM Status and VA in DME
To evaluate the association between the foveal external limiting membrane (ELM) status and visual acuity
(VA) in diabetic macular edema (DME), the spectral domain optical coherence tomography (SD-OCT) images of
127 eyes from 127 patients with DME were retrospectively reviewed. Additionally, the correlation between
the logarithm of the minimal angle of resolution (logMAR) VA and the statuses of the foveal ELM, inner
segment/outer segment (IS/OS) and cone outer segment tips (COST); foveal macular thickness (FMT); and
presence or absence of hard exudates (HE), serous retinal detachment (SRD) and vitreous adhesion were
evaluated. The integrity of the ELM, IS/OS and COST was classified into three categories: absent; disrupted;
and complete.
There was a strong correlation between VA and the statuses of the ELM (r=0.699, p<0.001), IS/OS
(r=0.716, p<0.001) and COST (r=0.471, p<0.001). There was no correlation between FMT and
logMAR VA (r=–0.036, p=0.687); however, when the correlation between FMT and VA was analyzed by
dividing patients into those with FMT ≤250 µm and those with FMT >250 µm, there was a
positive correlation between FMT and VA in eyes with FMT ≤250 µm (r=–0.601, p<0.0001)
and a negative correlation in eyes with FMT>250 µm (r=0.290, p<0.01). Other factors HE, SRD
and vitreous adhesion did not correlate with VA.
In conclusion, in DME, the ELM status may be as closely related to VA as the IS/OS status.
Source: Ito S, Miyamoto N, Ishida K, Kurimoto Y. Association between external limiting membrane
status and visual acuity in diabetic macular edema. Br J Ophthalmol. Nov 21. [Epub ahead of print].
DOI: 10.1136/bjophthalmol-2011-301418.
Treatment of Stable Corneal Neovascularization with Short-term
Topical Bevacizumab
In this prospective, nonrandomized, interventional case series, the authors evaluated the safety and efficacy
of topical bevacizumab in the treatment of corneal neovascularization.
They involved 20 eyes from 20 patients with stable corneal neovascularization and treated them with topical
1.0% bevacizumab for three weeks. They monitored these patients for a total of 24 weeks. Primary outcome
measures included neovascular area, defined as the area of the corneal vessels themselves; vessel caliber,
defined as the mean corneal vessel diameter; and invasion area, defined as the fraction of the total cornea
into which the vessels extended. The study authors closely monitored the occurrence of ocular and systemic
adverse events.
They observed that, compared with the baseline visit, patients exhibited a statistically significant improvement
in neovascular area by week six (p=.007) and in vessel caliber by week 12 (p=.006). At the final
visit, the authors found that neovascular area, vessel caliber and invasion area were reduced by 47.5%,
36.2% and 20%, respectively. The decreases in neovascular area and vessel caliber were statistically
significant (p<.001 and p=.003, respectively); however, the reduction in invasion area did
not reach statistical significance (p=.06). There were no significant changes in the secondary outcomes,
and there were no adverse events.
Short-term topical bevacizumab treatment reduced the extent of stable corneal neovascularization as measured
by neovascular area and vessel caliber with no associated adverse events. Interestingly, the degree of
treatment efficacy was inversely proportional to the baseline invasion area.
Source: Cheng SF, Dastjerdi MH, Ferrari G, et al. Short-term topical bevacizumab in the
treatment of stable corneal neovascularization. Am J Ophthalmol. 2012;154(6):940–948.
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