THE LATEST PUBLISHED RESEARCH

Treatment of Neovascular AMD Associated with Poor Initial Visual Acuity with Intravitreal Bevacizumab
To assess the efficacy of intravitreal bevacizumab injections for eyes with neovascular age-related macular degeneration (NVAMD) and poor visual acuity (VA), scientists conducted a retrospective study of 44 consecutive treatment-naïve eyes with NVAMD who had initial VA of 0.1 decimal or worse, and that were treated with intravitreal bevacizumab injections. For the purpose of the study, they reviewed charts, optical coherence tomography (OCT) and fluorescein angiograms (FAs).

Mean lesion size was 3375 (SD 2116) µm, all lesions showed sub- or intra-retinal fluid in OCT and active neovascularization comprised 41.6 (SD 17.7)% (range 10-90%) of the lesion area according to FA, the scientists observed. The mean follow-up time was 3.9 (SD 5.8) (range 1-21) months and patients received a mean of 2.6 (SD 2.4) bevacizumab injections (range 1-14), and mean VA improved from 1.85 (SD 0.64) to 1.52 (SD 0.77) LogMAR (p=0.002). Furthermore, the scientists noted that at final examination, 9 eyes (20%) had reduced VA, 10 eyes (23)%) had stable VA and 25 eyes (57%) had improved VA compared with baseline. Following treatment, mean macular thickness was reduced from 332 (SD 98) to 248 (SD 79) µm (p<0.0001).

Poor initial VA should not prevent the use of bevacizumab in eyes with NVAMD. The scientists who performed this study concluded that selection of patients with signs of active neovascularization based on ophthalmoscopy, OCT and FA may increase the likelihood of a favorable response to treatment.

Source: Galbinur T, Averbukh E, Banin E, et al. Intravitreal bevacizumab therapy for neovascular age-related macular degeneration associated with poor initial visual acuity. Br J Ophthalmol 2009;93(10):1351-1352. DOI: 10.1136/bjo.2009.158931.

Safety of Ranibizumab in Patients with Neovascular AMD
This 12-month, randomized (cohort 1) or open-label (cohort 2) multicenter clinical trial evaluated the safety and efficacy of intravitreal ranibizumab in a large population of subjects with neovascular age-related macular degeneration (AMD). It included 4,300 subjects with angiographically determined subfoveal choroidal neovascularization (CNV) secondary to AMD.

In this trial, cohort 1 subjects were randomized 1:1 to receive 0.3 mg (n=1,169) or 0.5 mg (n=1,209) intravitreal ranibizumab for 3 monthly loading doses. Dose groups were stratified by AMD treatment history (treatment-naïve vs. previously treated) and cohort 1 subjects were retreated on the basis of optical coherence tomography (OCT) or visual acuity (VA) criteria. Cohort 2 subjects (n=1,922) received an initial intravitreal dose of 0.5 mg ranibizumab and were retreated at physician discretion. Safety was evaluated at all visits and as for main outcome measures, safety outcomes included the incidence of ocular and nonocular adverse events (AEs) and serious adverse events (SAEs), whereas efficacy outcomes included changes in best-corrected VA over time.

It was noted that some 81.7 of cohort 1 subjects and 49.9% of cohort 2 subjects completed the 12-month study. The average total number of ranibizumab injections was 4.9 for cohort 1 and 3.6 for cohort 2. The incidence of vascular and nonvascular deaths during the 12-month study was 0.9% and 0.7% in the cohort 1 0.3 mg group, 0.8% and 1.5% in the cohort 1 0.5 mg group and 0.7% and 0.9% in cohort 2, respectively. The incidence of death due to unknown cause was 0.1% in both cohort 1dose groups and cohort 2, it was reported. Additionally, the number of vascular deaths and deaths due to unknown cause did not differ across cohorts or dose groups. Stroke rates were 0.7%, 1.2% and 0.6% in the 0.3 mg and 0.5 mg groups and cohort 2, respectively. Finally, at month 12, cohort 1 treatment-naïve subjects had gained an average of 0.5 (0.3 mg) and 2.3 (0.5 mg) VA letters and previously treated subjects had gained 1.7 (0.3 mg) and 2.3 (0.5 mg) VA letters.

In conclusion, intravitreal ranibizumab was safe and well tolerated in a large population of subjects with neovascular AMD. Ranibizumab had a beneficial effect on VA and future investigations will seek to establish optimal dosing regimens for persons with neovascular AMD.

Source: Boyer DS, Heier JS, Brown DM, et al. A phase IIIb study to evaluate the safety of ranibizumab in subjects with neovasulcar age-related macular degeneration. Ophthalmology 2009;116(9):1731-1739.

Effect of IVT Ranibizumab on Retinal Arteriolar Diameter in Neovascular AMD
Investigators studied the effect of intravitreal (IVT) ranibizumab on the retinal arteriolar diameter in patients with neovascular age-related macular degeneration (AMD) and concluded that their findings suggest that IVT ranibizumab induces sustained retinal arteriolar vasoconstriction in eyes with neovascular AMD.

Included were 10 eyes of 10 patients with previously untreated neovascular AMD and all eyes had three monthly IVT injections of ranibizumab and then were retreated as needed, based on visual acuity and optical coherence tomography (OCT) criteria. The study investigators measured the diameter of the retinal arterioles in vivo with a Retinal Vessel Analyzer (RVA) before the first IVT injection, 7 and 30 days after the first, the second and the third injection, and at month 12 of follow up.

They observed a significant vasoconstriction of the retinal arterioles following each one of the first three IVT injections of ranibizumab and that 30 days after the first, second and third injection, there was a mean decrease of 8.4 ± 3.2%, 11.9 ± 4.5% and 18.5 ± 7.2% respectively of the retinal arteriolar diameter compared to baseline (p<0.01). At month 12, the vasoconstriction was still present with a mean decrease of 19.1 ± 8.3% of the retinal arteriolar diameter compared to baseline (p<0.01). Furthermore, median number of ranibizumab injections was 4 (range 3-10) and the investigators found no correlation between the number of injections and % diameter decrease at month 12 (r = -0.54, p>0.1). There was no significant change in MAP during the period of follow up (p>0.05).

Source: Mendrinos E, Mangioris G, Papadopoulou D, et al. One year results of the effect of intravitrial ranibizumab on the retinal arteriolar diameter in patients with neovascular age-related macular degeneration. Invest Ophthalmol Vis Sci 2009;Sep 24 [Epub ahead of print].

Effect of Intravitreal Ranibizumab on Retinal Arteriolar Vasoconstriction in Patients with Neovascular AMD
In this prospective, consecutive interventional case series, Swiss investigators studied the effect of intravitreal (IVT) ranibizumab on the retinal arteriolar diameter in 11 eyes of 11 patients with previously untreated neovascular age-related macular degeneration (AMD).

All eyes had three monthly IVT injections of ranibizumab and the investigators measured the diameter of the retinal arterioles in vivo with a retinal vessel analyzer (RVA) before the first IVT injection and then 7 and 30 days after the first, second and third injections. Primary endpoints were changes in retinal arteriolar diameter and mean arterial pressure (MAP) after IVT ranibizumab, while secondary endpoints were changes in best-corrected visual acuity (BCVA), central retinal thickness and intraocular pressure after IVT ranibizumab, and appearance of adverse events during the follow-up period.

The investigators reported a significant decrease of the retinal arteriolar diameter after each IVT injection of ranibizumab. They noted a mean decrease of 8.1±3.2%, 11.5±4.4% and 17.6±7.4%, respectively, of the retinal arteriolar diameter 30 days after the first, second and third injections compared with baseline values (p<<0.01). Additionally, there was no significant change in MAP during the period of follow up (p>0.05) and 30 days after the third IVT injection of ranibizumab, mean BCVA improved by 6.5±4.9 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, and central retinal thickness decreased by 91±122 µm (p=0.03).

These results suggest that IVT ranibizumab may induce retinal arteriolar vasoconstriction in patients with neovascular AMD after IVT ranibizumab, the investigators noted. They concluded that further studies evaluating larger sample sizes are needed to confirm these results and potential adverse effects on the retinal circulation in patients with AMD and retinal vascular diseases.

Source: Papadopoulou DN, Mendrinos E, Mangioris G, et al. Intravitreal ranibizumab may induce retinal arterioloar vasoconstriction in patients with neovascular age-related macular degeneration. Ophthalmology 2009;116(9):1755-1761.

Impact of Excess Lead Levels in Retinal Tissues of Eyes with AMD
To measure lead and cadmium in retinal tissues of human donor eyes with and without age-related macular degeneration (AMD), the authors of this laboratory investigation determined lead and cadmium concentrations in retinal tissues (neural retina and retinal pigment epithelium [RPE]-choroid complex) in 25 subjects with AMD (50 donor eyes) and 36 normal subjects (72 donor eyes) by using inductively coupled plasma-mass spectrometry. They graded severity of AMD by using color fundus photographs as well as the Minnesota Grading System and compared differences in metal concentrations by using Wilcoxon rank-sum tests.

According to the authors, the neural retinas of subjects with AMD had increased lead concentrations (median, 12.0 ng/g; 25% to 75% interquartile range, 8 to 18 ng/g; n=25) compared with normal subjects (median, 8.0 ng/g; 25% to 75% interquartile range, 0 to 11 ng/g; p=.04; n=36). They reported no difference in lead concentration in the RPE-choroid complex between subjects with AMD (median, 198 ng/g; 25% to 75% interquartile range, 87 to 381 ng/g) and normal subjects (median, 172 ng/g; 25% to 75% interquartile range, 100 to 288 ng/g; p=.25). Cadmium concentration in the neural retina (median, 0.9 µg/g; 25% to 75% interquartile range, 0.7 to 1.8 µg/g) and RPE-choroid complex (median, 2.2 µg/g; 25% to 75% interquartile range, 1.8 to 3.7 µg/g) in subjects with AMD was not different from concentrations in the neural retina (median, 0.9 µg/g; 25% to 75% interquartile range, 0.7 to 1.4 µg/g; p=.32) and RPE-choroid complex (median, 1.5 µg/g; 25% to 75% interquartile range, 0.9 to 2.5 µg/g; p=.12) of normal subjects.

The authors concluded that AMD is associated with excess lead in the neural retina, and that this relationship suggests that metal homeostasis in AMD eyes is different from normal.

Source: Erie JC, Good JA, Butz JA. Excess lead in the neural retina in age-related macular degeneration. Am J Ophthalmol 2009;Sep 7 [Epub ahead of print]. DOI: 10.1016/j.ajo.2009.07.001.

Link Between RPE and Choriocapillaris in AMD
The purpose of this study was to examine the relationships between choriocapillaris (CC) and retinal pigment epithelial changes in age-related macular degeneration (AMD). Morphologic changes in the retinal pigment epithelium (RPEE)/choriocapillaris complex were quantified in dry and wet forms of AMD, and the results were compared with those in aged control eyes without maculopathy. It was concluded that the primary insult in GA appears to be at the level of the RPE, and that there is an intimate relationship between retinal pigment epithelial atrophy and secondary CC degeneration.

Postmortem choroids from three aged control subjects, five subjects with GA and three subjects with wet AMD were analyzed using a semiquantitative computer-assisted morphometric technique developed to measure the percentages of retinal pigment epithelial and CC areas in choroidal wholemounts incubated for alkaline phosphatase activity. Also, the tissues were subsequently embedded in methacrylate and were sectioned so that structural changes could be examined.

A linear relationship was noted between the loss of RPE and CC in GA and a 50% reduction in vascular area was found in regions of complete retinal pigment epithelial atrophy. Additionally, extreme constriction of remaining viable capillaries was found in areas devoid of RPE and adjacent to active choroidal neovascularization (CNV) in wet AMD, CC dropout was evident in the absence of retinal pigment epithelial atrophy, resulting in a 50% decrease in vascular area. Lumenal diameters of the remaining capillaries in wet AMD eyes were similar to those in control eyes.

In conclusion, CC degeneration occurs in the presence of viable RPE in wet AMD. The RPE in regions of vascular dropout are presumably hypoxic, which may result in an increase in VEGF production by the RPE and stimulation of CNV.

Source: McLeod DS, Grebe R, Bhutto I, et al. Relationship between RPE and choriocapillaris in age-related macular degeneration. Invest Ophthalmol Vis Sci 2009;50(10):4982-4991.

Progression of GA Associated with AMD
To characterize progression of geographic atrophy (GA) associated with age-related macular degeneration (AMD) in the Age-Related Eye Disease Study (AREDS) as measured by digitized fundus photographs, the authors of this study scanned, digitized and evaluated longitudinally fundus photographs from 181 of 4,757 AREDS participants with a GA area of at least 0.5 disc areas at baseline or from participants who developed bilateral GA during follow up. They determined GA area using planimetry and rates of progression from noncentral to central GA and of vision loss following development of central GA included the entire AREDS cohort.

According to the study authors, median initial lesion size was 4.3 mm² and average change in digital area of GA from baseline was 2.03 mm² (standard error of the mean, 0.24 mm²) at 1 year, 3.78 mm² (0.24 mm²) at 2 years, 5.93 mm² (0.34 mm²) at 3 years and 1.78 mm² (0.086 mm²) per year overall. Furthermore, median time to developing central GA after any GA diagnosis was 2.5 years (9.5% confidence interval, 2.0-3.0) and average visual acuity decreased by 3.7 letters at first documentation of central GA, and by 22 letters at year 5.

Growth of GA area can be reliably measured using standard fundus photographs that are digitized and subsequently graded at a reading center. The authors determined that development of GA is associated with subsequent further growth of GA, development of central GA and loss in central vision.

Source: The AREDS Research Group. Change in area of geographic atrophy in the age-related eye disease study. AREDS Report Number 26. Arch Ophthalmol 2009;127(9):1168-1174.

Head-to-Head Comparison of Bevacizumab and Ranibizumab for AMD
Scientists sought to report early outcomes of this prospective, double-masked, randomized, controlled trial comparing bevacizumab to ranibizumab for the treatment of age-related macular degeneration (AMD).

They randomized patients who met inclusion criteria 2:1 to bevacizumab or ranibizumab. Each patient contributed 1 eye to the study and all subjects and investigators (except for the pharmacist responsible for study assignments) were masked to treatment arms. The scientists checked visual acuity (VA) on Early Treatment Diabetic Retinopathy Study (ETDRS) chart and gave patients either bevacizumab or ranibizumab every month for the first 3 months, followed by optical coherence tomography-guided, variable-dosing schedule. Main outcomes measured were VA and foveal thickness.

A total of 20 patients completed the 6-month follow up; 13 patients received bevacizumab and 7 patients received ranibizumab. No subjects in either group lost more than 15 letters on ETDRS chart. The study scientists reported that the average preoperative VA as 31.6 letters in the bevacizumab group and 30.4 letters in the ranibizumab group. At 6 months follow up, mean vision was 46.4 letters in the bevacizumab group and 37.4 letters in the ranibizumab group. Two-tailed ttest failed to show statistical significance between the two group. Furthermore, patients in the bevacizumab group underwent an average of 5 injections, while patients in the ranibizumab group underwent a mean of 4 injections.

According to the scientists, early results of a head-to-head, randomized, double-masked, prospective, single-center, controlled trial between bevacizumab and ranibizumab show no difference in efficacy between the two treatments for choroidal neovascularization in the treatment of age-related macular degeneration. As this study conveys results of a small number of patients, further studies with larger sample sizes are needed to establish statistical significance.

Source: Subramanian ML, Ness S, Abedi G, et al. Bevacizumab vs ranibizumab for age-related macular degeneration: early results of a prospective double-masked, randomized clinical trial. Am J Ophthalmol 2009;Oct 5 [Epub ahead of print]. DOI: 10.1016/j.ajo.2009.07.009.

Changes in Macular Edema in Intravitreal Bevacizumab Therapy for RVO
This German study evaluated prognostic factors of response to intravitreal bevacizumab therapy of macular edema (ME) due to central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO).

Patients with ME due to CRVO (32 patients) or BRVO (38 patients) received intravitreal bevacizumab (2.5 mg/0.1 ml) at baseline and every 6 to 8 weeks if OCT showed persistent or recurrent ME. Visual acuity (EDTRS), ophthalmic examination and OCT were performed at baseline and at all follow-up visits. Additionally, 6 to 8 weeks after first injection, baseline factors (visual acuity, central retinal thickness, age and gender) were analyzed retrospectively between patients with resolved ME (group 1) and persisting ME (group 2). Baseline factors of patients with resolved ME since first injection (group A), with recurrent ME since baseline (group B) and with persistent ME since baseline (group C) were compared at last visit.

It was determined that in CRVO patients, central retinal thickness (CRT) and patients' age are prognostic predictors in bevacizumab therapy and that age of CRVO patients differed significantly between groups 1 and 2 after first injection, while CRT only showed a strong trend to thinner CRT. Age and CRT differed statistically significantly between groups A, B and C at last visit and in BRVO patients, none of the investigated factors revealed any prognostic value. In CRVO and BRVO patients, final CRT is correlated with the CRT after first injection.

CRT and age of patients have prognostic value in bevacizumab therapy of ME due to CRVO, it was reported. CRVO patients who benefit from therapy are significantly younger and have a lower CRT at baseline than patients with persisting ME. In BRVO patients, no predictive factors for effectiveness of bevacizumab therapy could be observed.

Source: Ach T, Hoeh AE, Schaal KB, et al. Predictive factors for changes in macular edema in intravitreal bevacizumab therapy for retinal vein occlusion. Graefes Arch Clin Exp Ophthalmol 2009;Sep 9 [Epub ahead of print]. DOI: 10.1007/s00417-009-1167-6.

Assessment of Vision-Related Quality of Life in Individuals with BRVO
Researchers evaluated vision-related quality of life in persons with branch retinal vein occlusion (BRVO) using the 25-item NEI Visual Function Questionnaire (VFQ-25) in this observational, cross-sectional, interviewer-administered study.

They included 46 patients with unilateral BRVO and analyzed and converted scores on the VFQ-25 to scaled scores per NEI VFQ-25 algorithms. They also recorded clinical data including age, gender, employment status, living arrangements, visual acuity, number of systemic diseases and duration of BRVO. Additionally, they compared subscale results to previously published data and performed subgroup analyses.

The researchers found that mean adjusted subscale responses amongst BRVO patients were higher (except for ocular pain) than known averages in patients with diabetic retinopathy, central retinal vein occlusion, age-related macular degeneration and low vision, but lower than known averages in a reference group of people without ocular disease. Subscale responses correlated significantly with visual acuity in the involved eye and this observation held true in 8 of 12 subscales, even in patients who maintained vision of 20/25 or better in the uninvolved eye. The study researchers reported that the General Health subscale and number of systemic diseases correlated significantly with both the General Vision and Peripheral Vision subscale scores. Moreover, they found no correlation between subscale responses and age.

They concluded that BRVO is a retinal vascular disease that is associated with a decrease in vision-related quality of life as determined by the VFQ-25 and that a decrease in VFQ-25 score is correlated with involved eye visual acuity, even with good visual acuity is maintained in the uninvolved eye.

Source: Awdeh RM, Elsing SH, Deramo VA, et al. Vision-related quality of life in persons with branch retinal vein occlusion (BRVO) using the 25-item NEI Visual Function Questionnaire. Br J Ophthalmol 2009; Sep 7 [Epub ahead of print]. DOI: 10.1136/bjo.2007.135913.

Determining Neovascularization in Patient with CRVO
To evaluate the prognostic value of interocular amplitude ratio of flicker electroretinogram (ERG) in determining the development of neovascularization in patients with central retinal vein occlusion (CRVO), researchers retrospectively reviewed the data obtained from flicker ERG in 51 CRVO patients. They determined that an interocular amplitude ratio of flicker ERG of 60% is a succinct, useful parameter in clinical practices for differentiating ischemic from nonischemic CRVO.

The researchers noted that of the 51 patients, 22 eyes that had enough follow up to differentiate ischemic CRVO from nonischemic CRVO were included for data analysis. They recorded the flicker ERG at a 30-Hz frequency after dark adaptation and averaged 10 sweeps.

A total of 11 eyes were ischemic and 11 were nonischemic, the researchers reported. Also, three amplitude parameters had the potential to explain the type of CRVO: amplitude of lesion eye (p=0.0001), interocular difference of amplitude (p<0.0001) and interocular ratio of amplitude (p<0.0001). The researchers reported that both an interocular amplitude difference of -23 µV and interocular amplitude ratio of 60% were very good cutoff points to differentiate ischemic from nonischemic CRVO. Receiver operating characteristic curve analysis revealed that each of the two cutoff values had a sensitivity and specificity of 100%.

Interocular comparison of amplitude is a good solution for avoiding the variability of ERG, concluded the researchers.

Source: Kuo HK, Kuo MT, Chen YJ, et al. The flicker electroretinogram interocular amplitude ratio is a strong prognostic indicator of neovascularization in patients with central retinal vein occlusion. Graefes Arch Clin Exper Ophthalmol 2009; Oct 8 [Epub ahead of print]. DOI: 10.1007/s00417-009-1205-4.

Outcomes of Refractory Diabetic Macular Edema Treated with Intravitreal Triamcinolone Acetonide
The researchers in this prospective, double-masked, randomized clinical trial sought to report the 5-year outcomes from a clinical trial of intravitreal triamcinolone acetonide (IVTA) in eyes with diabetic macular edema (DME) and impaired vision despite previous laser treatment.

They entered 69 eyes (41 patients) into the study, with 34 eyes initially receiving active treatment and 35 eyes receiving placebo. After completing the 2-year visit, all eyes, including those initially randomized to receive placebo, received IVTA according to prospectively defined guidelines. Five-year data were available for 44 of 67 eyes (66%) and for the 23 eyes with missing 5-year data, of which 13 received placebo and 10 received IVTA, the last observation was carried forward. Intervention consisted of intravitreal injection of 0.1 ml of 40 mg/ml triamcinolone acetonide with adjunctive laser therapy, where appropriate. Primary outcome in this trial was improvement of best-corrected logarithm of the minimum angle of resolution visual acuity by ≥ 5 letters after 5 years compared with baseline and 2 years and incidence of adverse events. Secondary outcome was the change in central macular thickness.

The study researchers found improvement of ≥5 letters after 5 years in 14 of 33 eyes (42%) initially treated with IVTA compared with 11 of 34 eyes (32%) initially treated with placebo (zGEE=0.81, p=0.4). According to the researchers, foveal thickness decreased by 30 µm (95% confidence interval, -47 to 107 µm) less in the initial-IVTA group than in the initial-placebo group at 5 years (zGEE=0.76, p=0.45); 5 of 11 eyes (45%) from the initial-IVTA group that were phakic at commencement of the third year required cataract surgery. A similar number of eyes from each group required ongoing treatment from the third year onward with both laser and IVTA, indicating that IVTA treatment for 2 years does not lead to reduction in the risk of recurrent edema.

The majority of eyes that initially improved with IVTA maintained their gain after 5 years, the researchers reported. They determined no new safety concerns and determined that IVTA treatment may be considered in carefully selected cases of impaired vision caused by advanced DME that are unresponsive to other interventions.

Source: Gillies MC, Simpson JM, Gaston C, et al. Five-year results of a randomized trial with open-label extension of triamcinolone acetonide for refractory diabetic macular edema. Ophthalmology 2009;Oct 1 [Epub ahead of print]. DOI: 10.1016/j.ophtha.2009.04.049.

Function and Structure of Central Retina in RP
Investigators studied patients with simplex, multiplex or autosomal recessive retinitis pigmentosa (RP, n=238; ages 9-82) with static chromatic perimetry to determine whether normal function and structure, as recently found in forms of Usher syndrome, also occurs in a population of patients with non-syndromic RP.

They evaluated a subset with optical coherence tomography (OCT) and measured co-localized visual sensitivity and photoreceptor nuclear layer thickness across the central retina to establish the relationship of function and structure. They also made comparisons to patients with Usher syndrome (n=83, ages 10-69).

Cross-sectional psychophysical data identified RP patients with normal rod- and cone-mediated function in the central retina and two other patterns with greater dysfunction were present. Longitudinal data confirmed progression could occur from normal rod and cone function to cone-only central islands. The retinal extent of normal laminar architecture by OCT corresponded to the extent of normal visual function in RP patients. Central retinal preservation of normal function and structure did not show a relationship with age or retained peripheral function. Furthermore, Usher syndrome results were like those in non-syndromic RP.

Regional disease variation is a well-known finding in RP. The observation that patients with presumed recessive RP can have regions with functionally and structurally normal retina was unexpected, according to the investigators. Such patients will require special consideration in future clinical trials of either focal or systemic treatment and whether there is a common molecular mechanism shared by forms of RP with normal regions of retina warrants further study.

Source: Jacobson S, Roman A, Aleman T, et al. Normal central retinal function and structure preserved in retinitis pigmentosa. Invest Ophthal Vis Sci 2009;Sep 24 [Epub ahead of print]. DOI: 10.1167/iovs.09-4372.