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Comparison of BCVA and Microperimetry Following Intravitreal Ranibizumab for Wet AMD

The researchers in this study compared the observed change in best-corrected visual acuity (BCVA) with the change in central retinal sensitivity pretreatment and 1 months after 3 consecutive treatments with ranibizumab in patients with wet age-related macular degeneration (AMD).

They performed microperimetric and BCVA assessment on 10 consecutive patients with untreated AMD before and 1 month after three consecutive treatments with ranibizumab. They also assessed BCVA at 1 months by using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and performed threshold microperimetry using a Goldman III stimulus to 45 points over the central 12 degrees of the macula. The researchers defined significant visual improvement after treatment as a change in BCVA ≥10 letters or, on microperimetry, a change in mean retinal sensitivity ≥2 dB.

One month after treatment, they discovered that the median change in BCVA was 6 letters (range, -15 to +12) and that the mean change in the mean retinal sensitivity was +2.86 dB (standard deviation, 1.55 dB). One patient recorded a significant improvement in BCVA compared with 8 patients who recorded a significant improvement in mean retinal sensitivity (p=0.016).

Compared with microperimetry, BCVA seems to significantly underestimate the change in visual function experienced by patients treated with ranibizumab.

Source: Squirrell D, Mawer N, Mody C, Brand C. Visual outcome after intravitreal ranibizumab for wet age-related macular degeneration: a comparison between best-corrected visual acuity and microperimetry. Retina 2010;30(3):436-442.

Intraretinal Neovascularization in Retinal Angiomatous Proliferation

The authors of this study sought to define the origin of intraretinal neovascularization in retinal angiomatous proliferation with spectral domain-optical coherence tomography (SD-OCT). They concluded that intraretinal neovascularization seems to originate from the deep retinal capillaries at the outer plexiform layer and grow toward the retinal pigment epithelium.

They retrospectively studied nine consecutive eyes of seven patients (two eyes of two men, seven eyes of five women) with untreated retinal angiomatous proliferation using fluorescein and indocyanine green angiography and SD-OCT. One eye had stage I disease, two eyes had stage II disease with no pigment epithelial detachment and six eyes had stage II disease with pigment epithelial detachment. The authors evaluated the location of the intraretinal neovascularization, disruption of the retinal pigment epithelium (RPE), retinal edema and serous retinal detachments.

They noted that intraretinal neovascularization appeared as a highly reflective mass from the outer plexiform layer to the deeper layer in seven eyes. The underlying RPE was disrupted beneath the intraretinal neovascularization in all eyes. The authors reported that all eyes had retinal edema around the intraretinal neovascularization and they saw serous retinal detachments in only two eyes with stage II disease with pigment epithelial detachment. Furthermore, intraretinal neovascularization originated outside the foveal avascular zone in all eyes.

Source: Matsumoto H, Sato T, Kishi S. Tomographic features of intraretinal neovascularization in retinal angiomatous proliferation. Retina 2010;30(3):425-430.

Intravitreal Triamcinolone Acetonide with PDT and Intravitreal Bevacizumab Versus PDT for Retinal Angiomatous Proliferation

Researchers in Japan conducted this retrospective, observational case series to compare the efficacy of combined therapy with intravitreal triamcinolone (IVTA) and photodynamic therapy (PDT; IVTA plus PDT) with intravitreal bevacizumab (IVB) and PDT (IVB plus PDT) for patients with retinal angiomatous proliferation (RAP).

They retrospectively reviewed 25 treatment-naïve eyes of 22 Japanese patients (11 men, 11 women) with RAP and treated 12 eyes of 11 patients with combined therapy of IVTA plus PDT from September 1, 2004 through July 31, 2006. They treated 13 eyes of 11 patients with combined therapy of IVB plus PDT from February 1, 2007 through January 31, 2008.

In 12 eyes treated with IVTA plus PDT, the mean best-corrected visual acuity (BCVA) levels at baseline and 12 months were 0.29 and 0.13, respectively. The researchers observed a significant (p<.05) decline in the mean BCVA from baseline at 12 months. In 13 eyes treated with IVB plus PDT, the mean BCVA levels at baseline and 12 months were 0.25 and 0.37. The researchers also observed a significant improvement (p<.05) in the mean BCVA from baseline and at 12 months, the difference in BCVA between the two groups was significant (p<.05). Additionally, the mean numbers of treatments at 12 months in the IVTA plus PDT group and the IVB plus PDT group were 2.7 and 1.6, respectively. The difference between the two treatments reached significance (p<.05) and no complications developed.

Compared with IVTA plus PDT, IVB plus PDT was significantly more effective in maintaining and improving visual acuity and in reducing the number of treatment for patients with RAP, the researchers determined.

Source: Saito M, Shiragami C, Shiraga F, et al. Comparison of intravitreal triamcinolone acetonide with photodynamic therapy and intravitreal bevacizumab with photodynamic therapy for retinal angiomatous proliferation. Am J Ophthalmol 2010;149(3):472-481.e1.

Treatment Efficacy of Bevacizumab for CNV Secondary to Pathologic Myopia

German researchers used this consecutive case series to evaluate whether the early effects seen under anti-vascular endothelial growth factor (VEGF) treatment can be maintained over longer follow-up intervals.

They included all patients at the Centre for Ophthalmology, Tuebingen, with a 2-year follow-up after treatment with 1.25 mg of bevacizumab alone or in combination with photodynamic therapy (PDT). They analyzed 21 eyes from 19 patients in the retrospective evaluation of best-corrected visual acuity (BCVA) and central foveal thickness (CFT).

According to the researchers, mean logMAR BCVA improved from 0.64 at baseline to 0.55 after 1 year (p=0.32) and remained 0.55 at 2 years (p=0.23). A subgroup analysis showed that mean logMAR BCVA in the monotherapy group improved from 0.7 to 0.5 at 2 years (n=11, p=0.06). Also, mean logMAR BCVA changed from 0.55 to 0.59 at 2 years (n=10, p=0.69) in the combined therapy group and mean CFT decreased significantly in both groups by 168 µm (p<0.001) and 76 µm (p<0.05) in the monotherapy and in the combined groups, respectively. The researchers observed no complications or adverse effects.

Although they admit that the limitations of the study design have to be acknowledged and carefully discussed, they found no obvious superiority of a combined treatment for myopic choroidal neovascularization (CNV), at least in terms of the functional outcome and the injection frequency. The results indicate that bevacizumab might be beneficial in the treatment of patients with CNV secondary to pathologic myopia.

Source: Voykov B, Gelishken F, Inhoffen W, et al. Bevacizumab for choroidal neovascularization secondary to pathologic myopia: is there a decline of the treatment efficacy after 2 years? Graefes Arch Clin Exp Ophthalmol 2010;248(4):543-550.

Treatment Efficacy of Ranibizumab for CNV Secondary to Pathologic Myopia

Scientists conducted this prospective case series of 32 eyes (32 patients) to evaluate the efficacy of intravitreal injections of ranibizumab in choroidal neovascularization (CNV) secondary to pathologic myopia.

The patients in this case series were affected with CNV secondary to pathologic myopia treated by intravitreal injections of ranibizumab. The scientists performed best-corrected visual acuity (BCVA), fundus examination, fluorescein angiography, indocyanine green angiography and spectral domain-optical coherence tomography for the diagnosis of myopic CNV. They also performed BCVA and central retinal thickness measurement monthly during the follow up.

According to the study scientists, the median number of injections was 3 with a median follow up of 17 months. They reported that the median visual acuity at baseline was 20/100 and improved to 20/50 at final examination (p<0.0001) and that the median visual acuity at baseline was 20/100 and improved to 20/50 at final examination (p<0.0001). BCVA improved ≥3 lines in 15 of 32 eyes (46.8%). The scientists noted that the median central thickness was 336 µm (range, 179-663 µm) at baseline and 223 µm (range, 125-465 µm) at final examination (p<0.0001). They reported no severe drug-related side effect.

In this series of myopic CNV, intravitreal injections of ranibizumab showed visual acuity improvement and retinal thickness reduction. The scientists involved in this study recommend further prospective multicentric clinical trials to evaluate the safety and efficacy of this treatment.

Source: Lalloum F, Souied EH, Bastuji-Garin S, et al. Intravitreal ranibizumab for choroidal neovascularization complicating pathologic myopia. Retina 2010;30(3):399-406.

Intravitreal Anti-VEGF Versus PDT for Myopic CNV

To compare visual outcomes after treatment with intravitreal antivascular endothelial growth factor (anti-VEGF) injection or photodynamic therapy (PDT) in patients with myopic choroidal neovascularization (CNV), 142 eyes of 128 consecutive patients treated with anti-VEGF (ranibizumab or bevacizumab) and/or PDT for myopic choroidal neovascularization were retrospectively reviewed.

Patients were categorized into 3 groups: PDT (51 eyes), anti-VEGF (63 eyes) and a combination group (PDT with anti-VEGF) (28 eyes) and corrected visual acuity values at baseline and 3, 6, 9 and 12 months after treatment were compared.

It was reported that the anti-VEGF group showed a significant postoperative improvement in visual acuity compared with the PDT and combination groups (p=0.01 and 0.04, respectively). The anti-VEFG group demonstrated visual improvement from baseline at every follow-up visit after treatment (p=0.04, 0.02, 0.01 and 0.002, respectively). It was also noted that the anti-VEGF group showed visual improvement (Snellen equivalent) from 0.57 logarithm of the minimum angle of resolution (0.27) to 0.33 logarithm of the minimum angle of resolution (0.47) (p=0.01). Furthermore, 98.4% of patients in the anti-VEGF group and 92.8% of those in the combination group lost <15 letters from baseline visual acuity compared with 72.6% in the PDT group (p=0.001 and 0.02, respectively). In the anti-VEGF group, 397% of patients improved from baseline by 15 or more letters compared with 17.7% in the PDT group (p=0.02) and 21.4% in the combination group (p=0.07).

It was determined that intravitreal anti-VEGF injection is superior to PDT alone or a combination of PDT with anti-VEGF for treating myopic choroidal neovascularization.

Source: Yoon J, Byun YJ, Koh HJ. Intravitreal anti-vegf versus photodynamic therapy with verteporfin for treatment of myopic choroidal neovascularization. Retina 2010;30(3):418-424.

Results of 2-Year Treatment of Myopic CNV with Intravitreal Bevacizumab

The authors of this Spanish prospective, non-randomized, interventional case series study sought to report the changes in best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) in highly myopic choroidal neovascularization (CNV) treated by intravitreal bevacizumab at 2 years. The study included 19 highly myopic eyes from 18 patients with subfoveal and juxtafoveal CNV treated by three monthly intravitreal injectionsof 1.25 mg bevacizumab. The authors evaluated patients for BCVA and OCT and baseline and then monthly for 2 years.

They reported that 11 eyes were naïve for treatment and 8 eyes had been previously treated by photodynamic therapy (PDT). LogMAR BCVA averaged 0.54 (SD 0.25, range 0.2-1.0; Snellen 20/69) at baseline; 0.40 (SD 0.35, range 0.0—1.0; Snellen 20/50) at 1 year; and 0.47 (SD 0.31, range 0.0—1.0; Snellen 20/59) at 2 years (p=0.04 and p=0.20, respectively, Studentïs t test paired data).

The study authors performed re-treatment in four eyes during the first year: three eyes at month six and one eye at month 12. Four eyes required one re-injection during the second year at months 14, 18, 20 and 2444. The detected neither ocular nor systemic adverse reactions.

They determined that intravitreal bevacizumab seems to be effective for subfoveal and juxtafoveal CNV in highly myopic eyes. BCVA gain decreases and is no longer significant by the end of the second year.

Source: Ruiz-Moreno JM, Montero JA. Intravitreal bevacizumab to treat myopic choroidal neovascularization: 2-year outcome. Graefes Arch Clin Exp Ophthalmol 2010; March 10 [Epub ahead of print]. DOI: 10.1007/s00417-010-1340-y.

Results of Long-Term Full Macular Translocation for CNV

The authors of this retrospective, interventional Japanese case series reported the long-term (>5 years) results of full macular translocation in patients with choroidal neovascularization (CNV).

A total of 32 eyes of 32 patients who had undergone full macular translocation for CNV were involved in this study. The median follow up was 6.5 years (range, 5.2 to 7.7 years). The authors evaluated the best-corrected visual acuity, fundus examination results obtained before and 1 and 5 years after operation and postoperative complications. At the 1-year follow up, they observed foveal retinal pigment epithelium atrophy in only 3 eyes (12%), and the mean logarithm of the minimal angle of resolution (logMAR) visual acuity (VA) at that time (1.39 ± 0.67) was not significantly changed from that before surgery (logMAR, 1.31 ± 0.66) in 25 eyes with age-related macular degeneration (AMD). At 5-year follow up, however, the authors found that foveal retinal pigment atrophy increased (18 eyes; 72%), and final mean logMAR VA (1.88 ± 0.76) was significantly lower (p<.01). Five eyes with myopic CNV maintained their VA from before operation (mean logMAR, 0.88 ± 0.35) until final follow up (mean logMAR, 0.73 ± 0.31). The study authors reported that the final VA was significantly better in myopic CNV than in exudative AMD on multiple regression analysis (p=.019). They determined that long-term follow up of full macular translocation showed that the final VA was poor in AMD, but relatively better in myopic CNV.

Source: Yamada Y, Miyamura N, Suzuma K, Kitaoka T. Long-term follow-up of full macular translocation for choroidal neovascularization. Am J Ophthalmol 2010;149(3):453-457.e1.

Intravitreous Dexamethasone Drug Delivery System for DME

After evaluating the safety and efficacy of a dexamethasone intravitreous drug delivery system (DDS) in eyes with diabetic macular edema (DME), the authors of this study found that, in eyes with persistent DME, treatment with 700 µg of intravitreal dexamethasone DDS is well tolerated and produces significant improvements in best-corrected visual acuity (BCVA), central retinal thickness and fluorescein leakage compared with observation (statistically significant at day 90).

They randomized patients with persistent macular edema (90 days' duration) to treatment with 700 µg or 350 µg of dexamthasone DDS or observation and designated one eye from each patient as the study eye. The analysis is of the eyes in this study with DME (n=171). According to the authors, the primary outcome measure was the proportion of eyes that achieved an improvement in BCVA of 10 letters or more from baseline at day 90. Other outcomes measured included fluorescein leakage, central retinal thickness and safety parameters.

The study authors saw a BCVA improvement of 10 letters or more at day 90 in more eyes in the 700-µg group (33.3%) and 350-µg group (21.1%) than the observation group (12.3%; p=.007 vs 700-µg group). At day 180, they saw a BCVA improvement of 10 letters or more in 30% of eyes in the 700-µg group, 19% in the 350-µg group, and 23% in the observation group (p≥.4 for treated vs observed eyes). Furthermore, there were significantly greater improvements in central retinal thickness and fluorescein leakage in treated eyes than observed eyes (p=.03; day 90). The authors also reported that dexamethasone was well tolerated.

Source: Haller JA, Kupperman BD, Blumenkranz MS, et al. Randomized controlled trial of an intravitreous dexamethasone drug delivery system in patients with diabetic macular edema. Arch Ophthalmol 2010;128(3):289-296.

Intravitreous Dexamethasone Drug Delivery System for DME

After evaluating the safety and efficacy of a dexamethasone intravitreous drug delivery system (DDS) in eyes with diabetic macular edema (DME), the authors of this study found that, in eyes with persistent DME, treatment with 700 µg of intravitreal dexamethasone DDS is well tolerated and produces significant improvements in best-corrected visual acuity (BCVA), central retinal thickness and fluorescein leakage compared with observation (statistically significant at day 90).

They randomized patients with persistent macular edema (90 days' duration) to treatment with 700 µg or 350 µg of dexamthasone DDS or observation and designated one eye from each patient as the study eye. The analysis is of the eyes in this study with DME (n=171). According to the authors, the primary outcome measure was the proportion of eyes that achieved an improvement in BCVA of 10 letters or more from baseline at day 90. Other outcomes measured included fluorescein leakage, central retinal thickness and safety parameters.

The study authors saw a BCVA improvement of 10 letters or more at day 90 in more eyes in the 700-µg group (33.3%) and 350-µg group (21.1%) than the observation group (12.3%; p=.007 vs 700-µg group). At day 180, they saw a BCVA improvement of 10 letters or more in 30% of eyes in the 700-µg group, 19% in the 350-µg group, and 23% in the observation group (p≥.4 for treated vs observed eyes). Furthermore, there were significantly greater improvements in central retinal thickness and fluorescein leakage in treated eyes than observed eyes (p=.03; day 90). The authors also reported that dexamethasone was well tolerated.

Source: Haller JA, Kupperman BD, Blumenkranz MS, et al. Randomized controlled trial of an intravitreous dexamethasone drug delivery system in patients with diabetic macular edema. Arch Ophthalmol 2010;128(3):289-296.

Assessment of Celecoxib and Microdiode Pulse Laser Treatment of DME

Investigators conducted this prospective, factorial, randomized, multicenter trial to evaluate combined anti-inflammatory therapy and laser approaches for treating patients with diabetic macular edema (DME).

They compared cyclo-oxygenase-2 inhibitor (celecoxib) with placebo and diode grid laser with standard Early Treatment Diabetic Retinopathy Study focal laser treatment in 86 participants with DME. The primary outcome is change in visual acuity of ≥15 letters from baseline, and the secondary outcomes include a 50% reduction in the retinal thickening of DME measured by optical coherence tomography and a 50% reduction in leakage severity on fluorescein angiography.

According to the investigators, visual acuity and retinal thickening data from >2 years of follow up did not show evidence of differences between the medical and laser treatments. However, participants assigned to the celecoxib group were more likely to have a reduction in fluorescein leakage when compared with the placebo group (odds ratio = 3.6; p<0.01).

They noted that this short-term study did not find large visual function benefits of treatment with celecoxib or diode laser compared with those of standard laser treatment. They did observe a suggestive effect of celecoxib in reducing fluorescein leakage.

Source: Chew E, Kim J, Coleman H, et al. Preliminary assessment of celecoxib and microdiode pulse laser treatment of diabetic macular edema. Retina 2010;30(3):459-467.

Outcome of Retinectomy in Proliferative Vitreoretinopathy

In this retrospective, nonrandomized, interventional case series, investigators described the functional and anatomic results of retinectomy without scleral buckling for anterior proliferative vitreoretinopathy in eyes that did not undergo previous buckling surgery.

They reviewed the results of 123 consecutive cases of retinectomy for rhegmatogenous retinal detachment complicated by anterior proliferative vitreoretinopathy. The primary outcome measure was anatomic success, defined as complete retinal reattachment. Secondary outcome measures were final anatomic success, final visual acuity outcome, number of operations required for retinal reattachment, baseline extent of proliferative vitreoretinopathy, ocular pressure at final follow up, extent of retinectomy and occurrence of complications. According to the investigators, the anatomic success rate was 77.2%. Final attachment rate was 95.9%, reached after 1 rhegmatogenous retinal detachment reoperation in 21 cases and after 2 rhegmatogenous retinal detachment reoperations in 4 cases. The investigators had a low rate of postoperative hypotony (4.1%); visual acuity was significantly improved from 2.10 to 1.44 logarithm of the minimal angle of resolution units (p<.001). Improvement was related significantly to retinectomy extent and primary anatomic success.

The study investigators reported that their results show that primary retinectomy without scleral buckling has good anatomic and functional results.

Source: Tan HS, Mura M, Oberstein SY, de Smet MD. Primary retinectomy in proliferative vitreoretinopathy. Am J Ophthalmol 2010;149(3):447-452.

Effect of Vitrectomy Without Endotamponade in Proliferative Diabetic Retinopathy with Tractional Retinal Detachment

This clinical, interventional case-series study evaluated the long-term results of vitreoretinal surgery without the use of intraocular silicone oil or gas in patients with proliferative diabetic retinopathy and tractional retinal detachment.

Included in this study were 168 eyes (150 patients) with diabetic tractional retinal detachment that were consecutively treated by pars plana vitrectomy without endotamponade during a study period of 7 years. Per selection criterion, retinal defects did not develop or were not observed in any of the study participants before or during surgery. The surgery included pars plana vitrectomy, removal of epiretinal membranes and retinal endolaser coagulation. Additionally, combined cataract surgery was performed in 33 eyes (20%). The mean follow up was 23 ± 14 months (range, 12-65 months).

It was reported that in 158 eyes (94%), the retina reattached after surgery and remained attached until the end of follow up. Subretinal fluid absorbed completely within 2 months after surgery. Best-corrected visual acuity improved in 126 eyes (75%) and remained unchanged in 19 eyes (11%). Mean best-corrected visual acuity improved from 2.22 ± 1.22 at baseline to 1.24 ± 1.00 at final follow up (p<0.001) and at the end of follow up, 11 eyes (7%) showed iris neovascularization. Nine of these 11 eyes developed iris neovascularization after surgery. Moreover, in multivariate logistic regression, the only factor associated with postoperative rubeosis iridis was preexisting rubeosis iridis (odds ratio, 6.4).

Vitreoretinal surgery for tractional retinal detachment in proliferative diabetic retinopathy may not necessarily be combined with an ocular endotamponade if there were no pre- or intraoperative retinal breaks, it was concluded.

Source: Tao Y, Jiang YR, Li XX, et al. Long-term results of vitrectomy without endotamponade in proliferative diabetic retinopathy with tractional retinal detachment. Retina 2010;30(3):447-451.

Effect of Uniform Vesicles of Silicone Oil on RPE Cells

This Chinese study aimed to test the effects of vesicles of silicone oil (VSO), which were prepared by a novel membrane emulsification technique, on the migration and proliferation of human retinal pigment epithelial (hRPE) cells in vitro.

VSO were produced by extrusion of the oil through a Supor membrane (Pall Life Sciences, Port Washington, NY) with 0.45 µm pore size under a pressure of 0.1 MPa. To asses whether hRPE cells could phagocytize VSO, hRPE cells were incubated with stained 25% VSO for 24 hours. A wound-healing model was used by denuding cells from a glass slide to assess the migration of hRPE cells and the cells were then incubated with 25%, 50% and 100% VSO with or without serum for up to 72 hours. The number of cells that had entered the denuded area was counted under a microscope and to assess the proliferative activity, the cells were incubated with 25%, 50% and 100% VSO, with or without serum, for 24 hours.

It was reported that a total of 100 nuclei were examined for each slide, and the numbers of stained argyrophilic nucleolar organizer regions (AgNORs) in the nuclei were measured. The mean vesicle diameter of VSO prepared was 4.25 ± 0.77 µm and it was noted that the stained 25% VSO were phagocytized by hRPE cells. After the cells cultured with serum-free Dulbecco's Modified Eagle Medium (DMEM) were incubated with VSO, the numbers of migratory cells at higher concentrations (50% and 100%) of VSO were significantly decreased (48.9 ± 5.37 and 10.6 ± 3.03 respectively) compared to controls (69.9 ± 9.88; p<0.01). After the cells cultured with serum-free DMEM were incubated with VSO, the number of AgNORs in nucleus at 100% VSO was significantly increased compared to controls (3.1 ± 0.72 vs 1.6 ± 0.6; p<0.01).

The result indicated that VSO inhibited the migration, but stimulated the proliferation of hRPE cells.

Source: Ma LN, Hui YN, Wang YS, et al. Inhibition of migration but stimulation of proliferation of human retinal pigment epithelial cells cultured with uniform vesicles of silicone oil. Graefes Arch Clin Exp Ophthalmol 2010;248(4):503-510.

Incidence of Retinal Vein Occlusion in a Study Setting

Scientists sought to determine the incidence of retinal vein occlusion (RVO) through a retrospective analysis of data from a randomized clinical trial (the Ocular Hypertension Treatment Study [OHTS].

They included 1,636 ocular hypertensive participants with a mean follow up of 9.1 years and managed participants in the medication and observation groups according to their original randomization assignment until June 1, 2002. At that time, they offered the observation participants ocular hypotensive treatment. This report includes data to July 1, 2005.

The scientists documented occurrences of RVO in study participants, categorized as branch, central or hemicentral vein occlusion and they identified potential RVO events by a keyword search of Adverse Event Reports, the Optic Disc Reading Center database, Endpoint Committee reviews and by response to a written request for information sent to each clinical site. Additionally, to confirm a potential RVO, they reviewed the complete OHTS chart and performed statistical analyses that included t tests, chi-square tests and Cox proportional hazards models. Incidence of RVO was the main outcome measure.

The scientists confirmed 26 RVOs (5 branch, 14 central and 7 hemicentral RVOS) in 23 participants (15 observation and 8 medication). The 10-year cumulative incidence of RVO was 2.1% in the observation group and 1.4% in the medication group (p=0.14; log-rank test). At baseline, participants who later developed an RVO were significantly older (65.1 vs 55.3 years; p=0.01) and had greater horizontal cup-to-disc ratios (p=0.0004).

The scientists noted that, although the incidence of RVO was higher in the observation group than the medication group, this difference did not attain significance. Consistent with some previous studies, older age and greater cup-to-disc ratio were associated with the development of RVO.

Source: Barnett EM, Fantin A, Wilson BS, et al. The incidence of retinal vein occlusion in the ocular hypertension treatment study. Ophthalmol 2010;117(3):484-488.

Examination of Differences in Acute Retinal Necrosis Caused by Two Viruses and the Effects of Intravitreal Foscarnet

This retrospective comparative case series studied the effects of intravitreal foscarnet and the clinical differences between varicella zoster virus (VZV) and herpes simplex virus (HSV) induced acute retinal necrosis (ARN). A total of 81 eyes (74 patients) were included in this case note analysis, which was performed in two tertiary referral centers. Presenting and final visual acuity, as well as progression to retinal detachment, were the main outcome measures.

It was reported that 33 eyes had HSV-ARN and 48 had VZV-ARN. The average age for HSV-ARN was 34 years and 51 years for VZV-ARN (p<0.001). Visual acuity on presentation was similar (p=0.48), but a larger proportion had better vision (≥20/60) in the HSV-ARN group (52%) than the VZV-ARN group (35%). A greater proportion of eyes with poor vision (≤20/200) was found at the 12-month follow up in the VZV-ARN group (60%) compared with the HSV-ARN group (35%) and a greater degree of visual loss in the VZV-ARN group (0.4 logarithm of the minimum angle of resolution [logMAR]) compared with the HSV-ARN group (0.04 logMAR) was detected (p=0.016). It was noted that retinal detachment was 2.5-fold more common in VZV-ARN (62%) compared with HSV-ARN (24%) and when comparing eyes treated with (n=56) and without (n=25) intravitreal foscarnet, there was a 40% lower rate in retinal detachment (53.6% vs 75.0%) for VZV-ARN (p=0.23). The numbers with HSV-ARN were too small for analysis.

The results support the difference of outcome in HSV-ARN and VZV-ARN; therefore, viral identification serves as a key to predicting outcome in these patients. It was concluded that intravitreal foscarnet seems to be a useful adjunct for the treatment of ARN in that it reduced the rate of retinal detachment.

Source: Wong R, Pavesio CE, Laidlaw DA, et al. Acute retinal necrosis: the effects of intravitreal foscarnet and virus type on outcome. Ophthalmol 2010;117(3):556-560.

Association Between Retinal Vascular Tortuosity and Neuroretinal Rim

A population-based, cross-sectional study of Malay persons aged 40 to 80 years residing in Singapore was conducted to describe the association of retinal vascular tortuosity, measured quantitatively, with neuroretinal rim.

Following a standardized protocol, retinal vascular tortuosity was quantified using a semi-automated, computer-assisted program from retinal fundus photographs. Optic disc measurements including disc area, rim area and rim-to-disc area (RDA) ratio were obtained with a confocal scanning laser ophthalmoscope (Heidelberg Retinal Tomography II).

Reduced arteriolar and venular tortuosity were associated with a decrease in global RDA ratio (p=0.006 and p=0.001, respectively) in analyses adjusting for age, gender, spherical equivalent and retinal vascular caliber. It was observed that when compared to the arterioles, retinal venular tortuosity demonstrated a stronger association on RDA ratio. Moreover, the temporal-inferior region of the neuroretinal rim was most strongly associated with retinal vascular tortuosity.

Straighter retinal vessels were significantly associated with thinning neuroretinal rim. These findings may provide additional insights into geometrical retinal vascular changes seen in early glaucomatous optic neuropathy.

Source: Koh VT, Cheung CY, Zheng Y, et al. Relationship of retinal vascular tortuosity with neuroretinal rim: the Singapore Malay Eye Study. Invest Ophthalmol Vis Sci 2010; March 5 [Epub ahead of print].

Retinal Function Following Trabeculectomy in Glaucoma Patients

Investigators in Sweden examined retinal function after reduction of IOP by filtration surgery in patients with medically uncontrolled glaucoma. A total of 11 patients (11 eyes) with medically uncontrolled glaucoma underwent trabeculectomy in this interventional, prospective, consecutive case series. The investigators performed clinical investigation, visual field (testing with standard automated perimetry [SAP-Humphrey]), optical coherence tomography (OCT), full-field electroretinopgraphy (full-field ERG) and multifocal electroretinography (mfERG) preoperatively as well as 2 and 6 months after surgery. They saw no significant reduction in mean logMAR visual acuity 2 or 6 months after filtration surgery and the mean preoperative IOP of 27.1 (±6.2) mmHg decreased to 19.0 (±6.1) mmHg 2 months after surgery and to 17.1 (±3.4) mmHg 6 months after surgery (both p=0.001). The investigators noted that the reduction in IOP significantly decreased the number of anti-glaucoma agents used, from 3.7 ± 1.6 at baseline to 0.8 ± 0.9 2 months after surgery and to 1.3 ± 1.2 6 months after surgery (p=0.004 and p=0.008, respectively). The results of SAP, OCT and full-field ERG did not show any significant difference between pre- and postoperative values at any point in time. Additionally, the study investigators found no significant improvement with regard to the first positive peak (P1) amplitudes in the macular retina (area 1) or in the perimacular retina/periphery (area 2) when measured with mfERG 2 months after surgery. The mfERG examinations revealed significantly improved P1 amplitudes 6 months after surgery in both area 1 and area 2, compared with the preoperative values (p=0.042 and p=0.014, respectively). Furthermore, the investigators reported that the implicit time of P1 decreased significantly 6 months after surgery in area 2 compared with the preoperative values (p=0.023). They concluded that a significant lowering of IOP seems to improve the function of the central retina, as demonstrated by increased amplitudes and reduced implicit times assessed with mfERG.

Source: Wittström E, Schatz P, Lövestam-Adrian M, et al. Improved retinal function after trabeculectomy in glaucoma patients. Graefes Arch Clin Exp Ophthalmol 2010;248(4):485-495.