Early-Phase Perceptions of COVID-19's Impact on Ophthalmology Practice Patterns: A Survey from the Pan-American Association of Ophthalmology.

Purpose: The COVID-19 pandemic affected medical practice worldwide due to interventions to prevent spreading. Its effect on ophthalmology practices in Latin America has not yet been explored. We aimed to assess the perceptions about the pandemic from countries' ophthalmological national and subspecialty retina societies affiliated to the Pan-American Association of Ophthalmology (PAAO). Patients and Methods: A survey-based study of leaders of national ophthalmological and retinal societies was conducted. The survey was sent by email to 30 societies, from which 20 responded (12 countries, 66.6% response rate). It included closed- and open-ended questions about (1) operational capacity and precautions, (2) telemedicine and virtual care, (3) procedures, and (4) post-pandemic considerations. Results: There was a marked decline in ophthalmology patient visits (80-95%) and elective surgeries (90%) during 2020 compared to before the pandemic. Precautions like temperature checks, mask usage, and social distancing were widely implemented while personal protective equipment (PPE) availability varied. Telemedicine use was limited due to lack of experience with it. Reopening plans focused on maintaining precautions and gradually resuming activities. Economic and security concerns were raised, and adherence to guidelines was emphasized. Respondents acknowledged the need to adapt to a "new normal". Long duration drugs, fewer imaging studies, and shorter wait times were preferred; however, availability of long duration drugs was limited. Conclusion: The pandemic impacted ophthalmology in Latin America, with reduced patient visits, procedures, and surgeries. Delayed treatment and complications were likely the result of the pandemic.

A 24 month follow-up of refractory macular holes treated with an autologous transplantation of internal limiting membrane versus retina expansion technique.

BACKGROUND: To compare the functional and anatomic outcomes at 24 months of eyes with a primary macular hole that failed to close after a prior surgery and were treated with either an autologous transplantation of internal limiting membrane (AT-ILM) or the retina expansion (RE) technique. METHODS: Retrospective, single center, comparative study of 28 eyes with a macular hole that failed to close after a prior vitrectomy. All eyes had a size of ≥ 500 µm. Participants were divided into two groups according to the type of intervention performed: AT-ILM group (n = 14) and RE group (n = 14). Main outcomes measured were the MH closure rate assessed by spectral-domain optical coherence tomography (SD-OCT) and the best-corrected visual acuity (BCVA) at 24 months after surgery. RESULTS: Patients in the AT-ILM group experienced a statistically significantly improved post-operative BCVA (median 49.50 letters, range 20-66 letters) over the pre-operative BCVA (median 39 letters, range 18-52 letters) (p-value = 0.006 Wilcoxon paired sample test). In contrast, patients in the RE group did not achieve a statistically significant improvement (p-value = 0.328, Wilcoxon paired sample test). The median pre-operative BCVA was 35 letters (range 18-52 letters), whereas the median post-operative BCVA was 39 letters (range 16-66 letters). At 24 months of follow-up, 85.7% of patients in the AT-ILM group achieved closure compared to 57.1% in the RE group (p-value = 0.209, Fisher's exact test). Multivariate analysis showed that MH size and baseline BCVA were important determinants of post-operative BCVA. The baseline MH size was the only significant pre-operative factor that influenced MH closure. CONCLUSIONS: This study demonstrates similar closure rates for both groups however better visual outcomes were obtained with the AT-ILM.

Risk of Posterior Capsular Rupture during Phacoemulsification in Patients with the History of Anti-VEGF Intravitreal Injections: Results from the Pan-American Collaborative Retina Study (PACORES) Group.

PURPOSE: To assess the risk for capsular rupture during routine phacoemulsification in patients with a history of anti-VEGF injections and other possible risk modifiers such as treatment patterns, type of anti-VEGF agent, and experience of the surgeon, among others. METHODS: This study reviewed the medical records of 11,129 patients from 7 different hospitals in 5 countries. The study included 939 patients that underwent routine phacoemulsification and had a history of anti-VEGF therapy. We excluded patients with known risk factors for capsular rupture, as well as patients with a history of other retinal procedures. The study extracted data regarding general demographics, the number of previous injections, type of anti-VEGF agent, details of cataract surgery, and anti-VEGF treatment patterns. RESULTS: Overall prevalence of posterior capsular rupture: 7.45% (95% CI: 5.9-9.32%). The mean number of injections per patient was 3.37 ± 2.8. More than 50% of the patients received their last anti-VEGF injection within three months before cataract surgery. The complication rate during intravitreal injections was 1.07%. In the univariate analysis, the experience of the cataract surgeon (inexperience surgeons; OR: 2.93) and the history of prior anti-VEGF therapy (OR: 1.77) were significant risk indicators for PCR (p < 0.05). However, after controlling for age in the multivariate analysis, the trend did not reach a statistical significance. CONCLUSION: The risk for capsular rupture is higher in patients with a history of intravitreal anti-VEGF injections.

New Treatment Modalities for Neovascular Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is considered one of the main causes of severe vision loss in older adults. The neovascular form (nAMD) is an advanced stage, which is responsible for the most severe vision loss. Vascular endothelial growth factor (VEGF) is at present the main factor that leads to the development of a neovascular membrane and the increased leakage from the membrane to the retina. At present, anti-VEGF therapy is the only treatment that achieves vision gains in many patients and halts progression in most of them. VEGF blockade can be achieved with several molecules and various treatment regimens, which have been studied with excellent results. Unfortunately, real-world data has shown to be far less efficacious than clinical trials. This gap between clinical trials and real-world results is an unmet medical need that supports the necessity of new treatment modalities for nAMD. Of the various treatments being studied, anti-VEGFs of higher efficacy and longer durability are those more advanced in their development. Brolucizumab and abicipar pegol are 2 new anti-VEGF drugs that had positive results in phase 2 studies and are being tested in phase 3 trials at present. Other promising therapies are antiangiopoietin 2 molecules, which are in phase 2 development. At earlier stages of development but with promising results are squalamine, anti-VEGF-C and -D, and gene therapy. The future will give retina specialists a broad armamentarium with which patients may achieve high visual gains for the long term with a low treatment burden.

Un-explained visual loss following silicone oil removal: results of the Pan American Collaborative Retina Study (PACORES) Group.

PURPOSE: To report the incidence and clinical features of patients that experienced un-explained visual loss following silicone oil (SO) removal. METHODS: Multicenter retrospective study of patients that underwent SO removal during 2000-2012. Visual loss of ≥2 lines was considered significant. RESULTS: A total of 324 eyes of 324 patients underwent SO removal during the study period. Forty two (13%) eyes suffered a significant visual loss following SO removal. Twenty three (7.1%) of these eyes lost vision secondary to known causes. In the remaining 19 (5.9%) eyes, the loss of vision was not explained by any other pathology. Eleven of these 19 patients (57.9%) were male. The mean age of this group was 49.2 ± 16.4 years. Eyes that had an un-explained visual loss had a mean IOP while the eye was filled with SO of 19.6 ± 6.9 mm Hg. The length of time that the eye was filled with SO was 14.8 ± 4.4 months. In comparison, eyes that did not experience visual loss had a mean IOP of 14 ± 7.3 mm Hg (p < 0.0002) and a mean tamponade duration of 9.3 ± 10.9 months (p < 0.0001). CONCLUSIONS: An un-explained visual loss after SO removal was observed in 5.9% of eyes. Factors associated with this phenomenon included a higher IOP and longer SO tamponade duration.

Outcomes of cataract surgery in diabetic patients: results of the Pan American Collaborative Retina Study Group / Resultados da cirurgia de catarata em pacientes diabéticos: resultados do Pan-American Collaborative Retina Study Group

Purpose: This study was designed to evaluate the visual and anatomical outcomes after cataract surgery in diabetic patients with different intraoperative therapeutic strategies. Methods: The research design comprised of a multicentric, retrospective, interventional study conducted at 6 centers in Argentina, Brazil, Costa Rica, Puerto Rico, Spain, and Venezuela. We included 138 diabetic patients with at least 6-month follow-up following phacoemulsification and intraocular lens implantation. Best-corrected visual acuity (BCVA) and central subfield thickness were collected at baseline and at 1-, 2-, 3-, and 6-month follow-up. Of these, 42 cases were not treated with any intraoperative coadjuvant medication (Group 1), 59 patients received intraoperative bevacizumab (Group 2) and 37 patients received intraoperative triamcinolone (4 mg/0.1 ml) (Group 3). Results: The mean logMAR [± standard deviation (SD)] BCVA improved from 0.82 (± 0.43) at baseline, to 0.14 (± 0.23) at 6-month follow-up (p<0.001) in Group 1; from 0.80 (± 0.48) to 0.54 (± 0.45) (p<0.001) in Group 2; and from 1.0 (± 0.40) to 0.46 (± 0.34) (p<0.001) in Group 3. The mean central subfield thickness increased from 263.57 µm (± 35.7) at baseline to 274.57 µm (± 48.7) at 6-month follow-up (p=0.088) in Group 1; from 316.02 µm (± 100.4) to 339.56 µm (± 145.3) (p=0.184) in Group 2; and from 259.18 µm (± 97.9) to 282.21 µm (± 87.24) (p=0.044) in Group 3. Conclusion: Diabetic patients may significantly benefit from cataract surgery. This study provides evidence to support the use of intravitreal triamcinolone or bevacizumab at the time of cataract surgery in cases with pre-existent diabetic macular edema or moderate-severe non-proliferative diabetic retinopathy. .

Objetivo: Avaliar os resultados visuais e anatômicos após a cirurgia de catarata em pacientes diabéticos com estratégias terapêuticas intraoperatórias diferentes. Métodos: Estudo multicêntrico, retrospectivo, de intervenção realizado em 6 centros da Argentina, Brasil, Costa Rica, Porto Rico, Espanha e Venezuela. Foram incluídos 138 pacientes diabéticos com pelo menos 6 meses de seguimento após facoemulsificação com implante de lente intraocular. Acuidade visual melhor corrigida (BCVA) e a espessura subcampo central (CST ) foram coletadas no início e em 1, 2, 3 e 6 meses de seguimento. Destes, 42 casos não foram tratadas com qualquer co-adjuvante de medicamentos intra-operatório (Grupo 1), 59 pacientes receberam bevacizumab intraoperatório (Grupo 2), e 37 pacientes receberam triancinolona intraoperatória (4 mg/0,1 ml) (Grupo 3). Resultados: A média logMAR (± desvio-padrão [DP]) BCVA melhorou de 0,82 (± 0,43) no início do estudo, para 0,14 (± 0,23) aos 6 meses de seguimento (p<0,001) no Grupo 1; de 0,80 (± 0,48) para 0,54 (± 0,45) (p<0,001) no Grupo 2; e de 1,0 (± 0,40) para 0,46 (± 0,34) (p<0,001) no Grupo 3. A CST média aumentou de 263,57 µm (± 35,7) na linha de base para 274,57±48,7 µm em 6 meses acompanhamento (p=0,088) no Grupo 1; de 316,02 µm (± 100,4), para 339,56 µm (± 145,3) (p=0,184) no Grupo 2; e de 259,18 µm (± 97,9), para 282,21 µm (±87,24) (p=0,044) no grupo 3. Conclusões: Pacientes diabéticos podem se beneficiar significativamente da cirurgia de catarata. Este estudo parece fornecer evidências para apoiar o uso de triancinolona intravítrea ou bevacizumab no momento da cirurgia de catarata em casos com edema macular diabético preexistente (DME) ou retinopatia diabética não-proliferativa moderada a grave. .

Outcomes of cataract surgery in diabetic patients: results of the Pan American Collaborative Retina Study Group.

PURPOSE: This study was designed to evaluate the visual and anatomical outcomes after cataract surgery in diabetic patients with different intraoperative therapeutic strategies. METHODS: The research design comprised of a multicentric, retrospective, interventional study conducted at 6 centers in Argentina, Brazil, Costa Rica, Puerto Rico, Spain, and Venezuela. We included 138 diabetic patients with at least 6-month follow-up following phacoemulsification and intraocular lens implantation. Best-corrected visual acuity (BCVA) and central subfield thickness were collected at baseline and at 1-, 2-, 3-, and 6-month follow-up. Of these, 42 cases were not treated with any intraoperative coadjuvant medication (Group 1), 59 patients received intraoperative bevacizumab (Group 2) and 37 patients received intraoperative triamcinolone (4 mg/0.1 ml) (Group 3). RESULTS: The mean logMAR [± standard deviation (SD)] BCVA improved from 0.82 (± 0.43) at baseline, to 0.14 (± 0.23) at 6-month follow-up (p<0.001) in Group 1; from 0.80 (± 0.48) to 0.54 (± 0.45) (p<0.001) in Group 2; and from 1.0 (± 0.40) to 0.46 (± 0.34) (p<0.001) in Group 3. The mean central subfield thickness increased from 263.57 µm (± 35.7) at baseline to 274.57 µm (± 48.7) at 6-month follow-up (p=0.088) in Group 1; from 316.02 µm (± 100.4) to 339.56 µm (± 145.3) (p=0.184) in Group 2; and from 259.18 µm (± 97.9) to 282.21 µm (± 87.24) (p=0.044) in Group 3. CONCLUSION: Diabetic patients may significantly benefit from cataract surgery. This study provides evidence to support the use of intravitreal triamcinolone or bevacizumab at the time of cataract surgery in cases with pre-existent diabetic macular edema or moderate-severe non-proliferative diabetic retinopathy.

Intravitreal Bevacizumab (Avastin) for Diabetic Retinopathy: The 2010 GLADAOF Lecture.

This paper demonstrates multiple benefits of intravitreal bevacizumab (IVB) on diabetic retinopathy (DR) including diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) at 24 months of followup. This is a retrospective multicenter interventional comparative case series of intravitreal injections of 1.25 or 2.5 mg of bevacizumab for DME, PDR without tractional retinal detachment (TRD), and patients who experienced the development or progression of TRD after an intravitreal injection of 1.25 or 2.5 mg of bevacizumab before vitrectomy for the management of PDR. The results indicate that IVB injections may have a beneficial effect on macular thickness and visual acuity (VA) in diffuse DME. Therefore, in the future this new therapy could complement focal/grid laser photocoagulation in DME. In PDR, this new option could be an adjuvant agent to panretina photocoagulation so that more selective therapy may be applied. Finally, TRD in PDR may occur or progress after IVB used as an adjuvant to vitrectomy. Surgery should be performed 4 days after IVB. Most patients had poorly controlled diabetes mellitus associated with elevated HbA1c, insulin administration, PDR refractory to panretinal photocoagulation, and longer time between IVB and vitrectomy.

Endophthalmitis after pars plana vitrectomy: results of the Pan American Collaborative Retina Study Group.

PURPOSE: To determine the incidence of endophthalmitis after 20-, 23-, and 25-gauge pars plana vitrectomies (PPVs). METHODS: Retrospective comparative case series of consecutive patients who underwent 20-, 23-, or 25-gauge PPV at 11 centers from Latin America between 2005 to 2009. Pars plana vitrectomy cases were identified through a search of the billing records of each institution. Cases of PPV performed in the management of trauma, endophthalmitis, and combined PPV phacoemulsification cases were excluded. Endophthalmitis was diagnosed by clinical criteria regardless of the microbiologic results. The incidence of post-PPV endophthalmitis was compared between 20-, 23-, and 25-gauge PPVs. RESULTS: A total of 35,427 cases of PPV were identified during the study period (n = 19,865 for 20 gauge, n = 10,845 for 23 gauge, and n = 4,717 for 25 gauge). The 5-year post-PPV endophthalmitis incidence rates were 0.020% (4 of 19,865), 0.028% (3 of 10,845), and 0.021% (1 of 4,717) for 20 gauge, 23 gauge, and 25 gauge, respectively (P = 0.9685). CONCLUSION: Small-gauge transconjunctival PPV does not appear to increase the rates of post-PPV endophthalmitis.

Comparison of two doses of intravitreal bevacizumab as primary treatment for macular edema secondary to central retinal vein occlusion: results of the pan American collaborative retina study group at 24 months.

PURPOSE: The purpose of this study was to compare the injection burden, central macular thickness (CMT), and change in best-corrected visual acuity after injecting 1.25 mg or 2.5 mg bevacizumab as needed in patients with primary macular edema secondary to central retinal vein occlusion. METHODS: This is an interventional, retrospective, comparative multicenter study of 86 eyes with macular edema secondary to central retinal vein occlusion that were treated primarily with intravitreal bevacizumab (44 eyes, 1.25 mg; 42 eyes, 2.5 mg). The main outcome measures were the CMT and the change of best-corrected visual acuity at 24 months. RESULTS: All patients completed at least 24 months of follow-up. The mean number of injections per eye were 7.2 for the 1.25-mg dose group and 8.1 for the 2.5-mg dose group (P = 0.4492). At 24 months, in the 1.25-mg dose group, the logarithm of the minimal angle of resolution best-corrected visual acuity improved from baseline 0.35 +/- 0.57 units (P < 0.0001) versus 0.27 +/- 0.68 units for the 2.5-mg dose group (P < 0.0001). These differences were not statistically significant between both dose groups. In the 1.25-mg dose group, 25 (56.8%) eyes gained >or=3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity and 6 (13.6%) lost >or=3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity. In the 2.5-mg dose group, 24 (57.1 %) eyes improved >or=3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity and 7 (16.7%) lost >or=3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity. The CMT in the 1.25-mg dose group improved from 635 +/- 324 microm to 264 +/- 160 microm (P < 0.0001) versus 528 +/- microm to 293 +/- 137 microm in the 2.5-mg dose group (P < 0.0001). There was no statistically significant difference between both dose groups with regard to the CMT reduction. CONCLUSION: Intravitreal bevacizumab at doses up to 2.5 mg seems to be effective in improving visual acuity and reducing CMT in macular edema secondary to central retinal vein occlusion. There were no statistically significant differences between the two dose groups with regard to the number of injections, CMT, and change in visual acuity.

Intravitreal Bevacizumab (Avastin(®)) for Diabetic Retinopathy at 24-months: The 2008 Juan Verdaguer-Planas Lecture.

Diabetic retinopathy (DR) remains the major threat to sight in the working age population. Diabetic macular edema (DME) is a manifestation of DR that produces loss of central vision. Proliferative diabetic retinopathy (PDR) is a major cause of visual loss in diabetic patients. In PDR, the growth of new vessels is thought to occur as a result of vascular endothelial growth factor (VEGF) release into the vitreous cavity as a response to ischemia. Furthermore, VEGF increases vessel permeability leading to deposition of proteins in the interstitium that facilitate the process of angiogenesis and macular edema. This review demonstrates multiple benefits of intravitreal bevacizumab (IVB) on DR including DME and PDR at 24 months of follow up. The results indicate that IVB injections may have a beneficial effect on macular thickness and visual acuity (VA) in diffuse diabetic macular edema. Therefore, in the future this new therapy could replace or complement focal/grid laser photocoagulation in DME. In PDR, this new option could be an adjuvant agent to pan-retina photocoagulation so that more selective therapy may be applied. In addition, we report a series of patients in which tractional retinal detachment developed or progressed after adjuvant preoperative IVB in severe PDR.

Intravitreal bevacizumab for subfoveal choroidal neovascularization in age-related macular degeneration at twenty-four months: the Pan-American Collaborative Retina Study.

PURPOSE: To report the 24-month anatomic and Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) response after primary intravitreal bevacizumab (IVB) (Avastin; Genentech Inc., San Francisco, CA) (1.25 or 2.5 mg) in patients with subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). DESIGN: Retrospective, multicenter, interventional, comparative case series. PARTICIPANTS: We reviewed the clinical records of 180 consecutive patients (207 eyes) with subfoveal CNV secondary to AMD at 9 centers from 8 countries. METHODS: Patients were treated with at least 1 injection of IVB 1.25 mg (124 eyes [59.9%]) or 2.5 mg (83 eyes [40.1%]). Patients underwent ETDRS BCVA testing, ophthalmoscopic examination, optical coherence tomography (OCT), and fluorescein angiography (FA) at baseline and 1-, 3-, 6-, 12-, and 24-month visits. MAIN OUTCOME MEASURES: Changes in BCVA and OCT. RESULTS: The mean age of our patients was 74.3±7.5 years. The mean number of IVB injections per eye was 5.1 (range, 1-24 injections). In the 1.25 mg group, baseline BCVA improved from 20/235 (logarithm of the minimum angle of resolution [logMAR] 1.07) to 20/172 (logMAR 0.92) at 24 months (P<0.0001). Similar BCVA changes were observed in the 2.5 mg group. At baseline, the mean central macular thickness (CMT) by OCT in the 1.25 mg group was 308.4±127.52 µm, which was reduced to 269.35±97.92 µm, 262.1±94.81 µm, 264.03±97.06 µm, 245.91±89.52 µm, and 249.27±89.14 µm at 1, 3, 6, 12, and 24 months, respectively (P<0.0001). Similar changes were observed in the 2.5 mg group. In the 2.5 mg group, systemic complications included 2 new cases (2.6%) of arterial hypertension, 1 case (1.3%) of stroke, and 1 case (1.3%) of death. CONCLUSIONS: Primary IVB at a dose of 1.25 or 2.5 mg seems to provide stability or improvement in BCVA, OCT, and FA in subfoveal CNV secondary to AMD at 24 months. Our results show no significant difference regarding BCVA with IVB at doses of 1.25 or 2.5 mg.

Comparison of two doses of intravitreal bevacizumab as primary treatment for macular edema secondary to branch retinal vein occlusions: results of the Pan American Collaborative Retina Study Group at 24 months.

PURPOSE: The purpose of this study was to compare the injection burden, central macular thickness (CMT), and change in best-corrected visual acuity (BCVA) after injecting 1.25 mg or 2.5 mg of bevacizumab as needed in patients with primary macular edema secondary to branch retinal vein occlusion. METHODS: An interventional, retrospective, comparative multicenter study was conducted of 63 eyes with macular edema secondary to branch retinal vein occlusion that were treated primarily with intravitreal bevacizumab (38 eyes, 1.25 mg; 25 eyes, 2.5 mg). The main outcome measures were the CMT and the change of BCVA at 24 months. RESULTS: All patients completed at least 24 months of follow-up. The mean number of injections per eye was 3.6 in the 1.25-mg group and 4.3 in the 2.5-mg group (P = 0.4770). At 24 months, in the 1.25-mg group, the logarithm of the minimum angle of resolution BCVA improved from baseline 0.38 +/- 0.63 (P < 0.0001) units to 0.64 +/- 0.6 units for the 2.5-mg group (P < 0.0001). In the 1.25-mg group, 26 (68%) eyes gained > or =3 of Early Treatment of Diabetic Retinopathy Study visual acuity and 2 (5%) eyes lost > or =3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity. In the 2.5-mg group, 18 (72%) eyes improved > or =3 of Early Treatment of Diabetic Retinopathy Study visual acuity, and none of the eyes lost > or =3 lines of Early Treatment of Diabetic Retinopathy Study visual acuity. The CMT in the 1.25-mg group improved from 453 +/- 140 microm to 244 +/- 125 microm (P < 0.0001) versus 444 +/- 175 microm to 234 +/- 80 microm in the 2.5-mg group (P < 0.0001). There were no cases of endophthalmitis. No systemic adverse events were reported. CONCLUSION: Intravitreal bevacizumab at doses up to 2.5 mg seems to be effective in improving BCVA and reducing CMT in macular edema secondary to branch retinal vein occlusion. No statistically significant differences were found between the two dose groups with regard to the number of injections, CMT, and change in BCVA.

Primary intravitreal bevacizumab for diffuse diabetic macular edema: the Pan-American Collaborative Retina Study Group at 24 months.

PURPOSE: To report the 24-month anatomic and Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) response after primary intravitreal bevacizumab (Avastin; Genentech, Inc., San Francisco, CA; 1.25 or 2.5 mg) in patients with diffuse diabetic macular edema (DDME). In addition, a comparison of the 2 different doses of intravitreal bevacizumab (IVB) used is presented. DESIGN: Retrospective, multicenter, interventional, comparative case series. PARTICIPANTS: The clinical records of 115 consecutive patients (139 eyes) with DDME at 11 centers from 8 countries were reviewed. METHODS: Patients were treated with at least 1 intravitreal injection of 1.25 or 2.5 mg of bevacizumab. All patients were followed up for 24 months. Patients underwent ETDRS BCVA testing, ophthalmoscopic examination, optical coherence tomography (OCT), and fluorescein angiography (FA) at the baseline, 1-, 3-, 6-, 12-, and 24-month visits. MAIN OUTCOME MEASURES: Changes in BCVA and OCT results. RESULTS: The mean age of the patients was 59.4+/-11.1 years. The mean number of IVB injections per eye was 5.8 (range, 1-15 injections). In the 1.25-mg group at 1 month, BCVA improved from 20/150 (0.88 logarithm of the minimum angle of resolution [logMAR] units) to 20/107, 0.76 logMAR units (P<0.0001). The mean BCVA at 24 months was 20/75 (0.57 logMAR units; P<0.0001). Similar BCVA changes were observed in the 2.5-mg group: at 1 month, BCVA improved from 20/168 (0.92 logMAR units) to 20/118 (0.78 logMAR units; P = 0.02). The mean BCVA at 24 months was 20/114 (0.76 logMAR units; P<0.0001). In the 1.25-mg group, the mean central macular thickness (CMT) decreased from 466.5+/-145.2 microm at baseline to 332.2+/-129.6 microm at 1 month and 286.6+/-81.5 microm at 24 months (P<0.0001). Similar results were obtained in the 2.5-mg group. CONCLUSIONS: Primary IVB at doses of 1.25 to 2.5 mg seem to provide stability or improvement in BCVA, OCT, and FA in DDME at 24 months. The results show no evident difference between IVB at doses of 1.25 or 2.5 mg.