Changes in Retinal Thickness after Vitrectomy for Epiretinal Membrane with and without Internal Limiting Membrane Peeling.

PURPOSE: To investigate anatomic changes in retinal thickness (RT) and functional changes after vitrectomy for idiopathic epiretinal membranes (ERMs) with and without internal limiting membrane (ILM) peeling. METHODS: The medical records of 100 eyes of 96 patients with ERM who underwent vitrectomy and ERM removal were reviewed retrospectively. The RT was measured by optical coherence tomography, and the area was divided into 9 sections. The best-corrected visual acuity (BCVA), 9 RT areas, and incidence rates of recurrent ERM were compared between the groups with and without ILM peeling before the operation and 12 months postoperatively. RESULTS: Thirty-nine eyes that underwent vitrectomy with ILM peeling and 61 eyes that underwent vitrectomy without ILM peeling met the inclusion criteria. There were no significant differences between the groups in the BCVA and any of the RTs before the operation and 12 months postoperatively. The ERMs recurred in 8 (20.5%) of 39 eyes and 26 (42.6%) of 61 eyes in the groups with and without ILM peeling, respectively, with a difference that reached significance (p = 0.02) 12 months postoperatively. CONCLUSIONS: Vitrectomy for ERM affects the BCVA or the RTs 12 months postoperatively. Additional ILM peeling does not affect them, but it might reduce the ERM recurrence rate.

The effectiveness of vitrectomy for diffuse diabetic macular edema may depend on its preoperative optical coherence tomography pattern.

BACKGROUND: To investigate the effectiveness of vitrectomy for diffuse diabetic macular edema (DDME) and its dependence on optical coherence tomography (OCT) findings. METHODS: The records of 65 patients and 81 eyes who received vitrectomy for DDME and followed up for at least 6 months were retrospectively reviewed. All eyes were classified according to their morphological characteristics on OCT including sponge-like diffuse retinal thickening (SDRT: n = 13), cystoid macular edema (CME: n = 42), serous retinal detachment (SRD: n = 13), and the combination of all morphological characteristics (FULL: n = 13). The best-corrected visual acuity (BCVA) and spectral domain OCT were investigated preoperatively and at 1, 3, and 6 months postoperatively. RESULTS: At six months after surgery, BCVA in logMAR units was significantly improved in all groups except the SDRT group. The improvement was -0.04 ± 0.20 in the SDRT group (P = 0.504), -0.16 ± 0.24 in the CME group (P < 0.01), -0.32 ± 0.32 in the SRD group (P < 0.01), and -0.26 ± 0.19 in the FULL group (P < 0.01), and significantly better in eyes with subretinal fluid (SRF; the SRD and FULL groups) than in eyes without SRF (the SDRT and CME groups, P = 0.003). CONCLUSIONS: Vitrectomy can be a useful treatment option for DDME, particularly for eyes with SRF.

PHOTORECEPTOR OUTER SEGMENT LENGTH AND OUTER FOVEAL THICKNESS AS FACTORS ASSOCIATED WITH VISUAL OUTCOME AFTER VITRECTOMY FOR VITREOMACULAR TRACTION SYNDROME.

PURPOSE: To investigate the predictive factors for postoperative best-corrected visual acuity (BCVA) in patients with vitreomacular traction syndrome treated with vitrectomy. METHODS: The records of 21 patients with 21 eyes that underwent vitrectomy for vitreomacular traction syndrome and followed for at least 12 months were retrospectively reviewed. The BCVA and spectral domain optical coherence tomography findings were investigated preoperatively and at 1, 3, 6, and 12 months postoperatively. Axial length was measured preoperatively. The correlations between 12-month postoperative BCVA and preoperative parameters, including BCVA, age, axial length, central foveal thickness, outer foveal thickness, and photoreceptor outer segment length, were evaluated. RESULTS: Twelve-month postoperative BCVA was significantly negatively correlated with preoperative outer foveal thickness and photoreceptor outer segment length (outer foveal thickness: P = 0.029, r = -0.501; photoreceptor outer segment length: P = 0.022, r = -0.523, respectively) but not correlated with age, axial length, preoperative BCVA, and preoperative central foveal thickness (age: P = 0.346, r = 0.216; axial length: P = 0.333, r = 0.242; BCVA: P = 0.202, r = 0.290; central foveal thickness: P = 0.065, r = -0.410, respectively). CONCLUSION: Preoperative outer foveal thickness and photoreceptor outer segment length could be good predictive factors of postoperative BCVA in patients with vitreomacular traction syndrome.

Contrast Sensitivity after Pars Plana Vitrectomy: Comparison between Macula-On and Macula-Off Rhegmatogenous Retinal Detachment.

PURPOSE: To evaluate the contrast sensitivity (CS) of eyes successfully repaired by vitrectomy for rhegmatogenous retinal detachment (RRD) with or without preoperative macular involvement. METHODS: In this retrospective, consecutive, interventional case series, 109 eyes received primary vitrectomy for RRD, of which 36 with at least 12 months of follow-up and a best-corrected visual acuity (BCVA) ≥1 at 12 months postoperatively were investigated. The main outcome measurements were BCVA and CS at 12 months postoperatively. Patients with macula-on RRD preoperatively were included in the macula-on group, and patients with macula-off RRD preoperatively were included in the macula-off group. The between-group difference in CS under evening vision conditions was measured with a Takagi glare tester CGT-2000 at 6 visual angles and 13 contrast levels with and without glare. RESULTS: CS was significantly lower in the macula-off group for targets with visual angles of 1.6, 1.0, and 0.64° with glare (p < 0.05) and for the target with a visual angle of 0.64° without glare (p < 0.05). CONCLUSIONS: CS in the higher spatial frequency range (especially with glare) is reduced in macula-off RRD patients with good postoperative BCVA compared to macula-on RRD patients with good postoperative BCVA.

Long-term intraocular pressure changes after vitrectomy for epiretinal membrane and macular hole.

BACKGROUND: To investigate long-term intraocular pressure (IOP) changes after vitrectomy for epiretinal membrane (ERM) or macular hole (MH). METHODS: We retrospectively reviewed the medical records of 57 eyes with ERM and 61 eyes with MH that underwent vitrectomy. IOP levels and changes at 1, 3, 6, 12 months, and the final visit from baseline were evaluated in vitrectomized eyes and non-vitrectomized fellow eyes. RESULTS: In the ERM group, the mean follow-up period was 29.3 months; the mean preoperative IOP in the operated eyes was 12.9 ± 2.5 mmHg and the final IOP was 13.2 ± 2.9 mmHg. In the MH group, the mean follow-up period was 25.6 months; the mean preoperative IOP in the operated eyes was 13.3 ± 2.5 mmHg and the final IOP was 14.0 ± 3.2 mmHg. The mean final IOP of the fellow unoperated eyes was 13.0 ± 2.5 mmHg in the ERM group and it was 12.9 ± 3.2 mmHg in the MH group. A significant difference was found between the operated eyes and fellow eyes at the final visit in the MH group (P < 0.01) but not in the ERM group (P = 0.40). MH group was significantly at high risk of IOP increase after vitrectomy (P < 0.01). CONCLUSIONS: IOP increase after vitrectomy was found in some eyes with MH during long-term follow-up but it was unlikely in eyes with ERM.

Bimonthly injections of ranibizumab for age-related macular degeneration.

PURPOSE: To evaluate the efficacy of bimonthly intravitreal injections of ranibizumab for age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in a pilot study. METHODS: This study was a prospective, interventional case series. Thirty eyes of 30 patients received prospectively at least three bimonthly intravitreal injections of ranibizumab (0.5 mg/0.05 ml) without loading doses. The best-corrected visual acuity (BCVA) and the central retinal subfield thickness (CRST) were measured before and monthly after the injections. RESULTS: Twenty-eight patients received the three planned injections; one patient refused the third injection, one patient did not receive the third injection because blood pressure was raised, and one patient received a rescue injection at month 5 because of increased retinal thickness. The mean logarithm of the minimum angle of resolution (logMAR) BCVA was 0.44 ± 0.37 before treatment and significantly improved to 0.25 ± 0.34 at month 6 (p < 0.001). The mean CRST was 335 ± 85.9 µm before treatment and decreased significantly to 261 ± 78.1 µm at month 6 (p < 0.001). Nine of 30 patients received six planned injections for 12 months. The mean logMAR BCVA was 0.38 ± 0.39 before treatment and significantly improved to 0.18 ± 0.33 at month 12 (p = 0.005). The mean CRST was 360 ± 110.8 µm before treatment and decreased significantly to 249 ± 57.0 µm at month 12 (p = 0.025). CONCLUSIONS: Bimonthly injections of ranibizumab may be effective for treating AMD and PCV.

Aqueous vascular endothelial growth factor and ranibizumab concentrations after monthly and bimonthly intravitreal injections of ranibizumab for age-related macular degeneration.

PURPOSE: To evaluate vascular endothelial growth factor (VEGF) and ranibizumab concentrations in eyes with age-related macular degeneration (AMD) after monthly and bimonthly intravitreal ranibizumab (IVR) injections. METHODS: Aqueous humor samples were obtained from 26 eyes with AMD before and after IVR injections. Nine eyes received three monthly injections and 17 eyes received two bimonthly injections. The VEGF and ranibizumab concentrations were measured by enzyme-linked immunosorbent assay. RESULTS: The aqueous VEGF concentrations in the monthly injection group decreased below the lowest detectable limit in eight of nine eyes 1 month after the first injection and seven of nine eyes 1 month after the second injection (P < 0.001, mean baseline value, 94.7 pg/ml); the aqueous VEGF concentrations in the bimonthly injection group decreased below the lowest detectable limit in two of 17 eyes 2 months after the first injection (P < 0.001, mean baseline value, 152.4 pg/ml). The mean aqueous ranibizumab concentrations with monthly injections were 71.2 ng/ml 1 month after the first injection, and 96.3 ng/ml 1 month after the second injection. The mean aqueous ranibizumab concentrations in the bimonthly injection group were 2.5 ng/ml in 15 of 17 eyes, and below the lowest detectable limit in two of 17 eyes 2 months after the first injection. CONCLUSIONS: In this pilot study with limited follow-up, intravitreal injection of ranibizumab can suppress aqueous VEGF completely for 1 month in most cases. Its effect does not last for 2 months enough to suppress VEGF completely in most cases, although aqueous VEGF at 2 months after intravitreal injection of ranibizumab is less than that before injection in most cases.

Scleral imbrication combined with vitrectomy and gas tamponade for refractory macular hole retinal detachment associated with high myopia.

PURPOSE: To evaluate scleral imbrication with vitrectomy and gas tamponade for refractory macular hole retinal detachment associated with high myopia. METHODS: We retrospectively reviewed the medical records of eight eyes with macular hole retinal detachment and high myopia treated with temporal scleral imbrication, pars plana vitrectomy, and gas tamponade for refractory macular hole retinal detachment with history of pars plana vitrectomy. Retinal reattachment and macular hole closure were assessed. Postoperative changes in axial length and surgically induced astigmatism were evaluated. RESULTS: The retinas were reattached in all eyes and the macular holes closed in 6 (75%) eyes. The mean baseline logarithm of the minimum angle of resolution best-corrected visual acuity of 1.43 ± 0.48 significantly (P < 0.01) improved to 0.87 ± 0.34 at the final visit (889 ± 173 postoperative days). The mean baseline axial length of 29.5 ± 1.3 mm decreased significantly (P < 0.01) to 27.1 ± 1.9 mm 1 month after scleral imbrication and 28.1 ± 1.7 mm at the final visit (P < 0.05 vs. baseline, P = 0.13 vs. 1 month). The mean 1-month surgically induced astigmatism of 3.6 ± 1.4 diopters (D) after scleral imbrication significantly (P < 0.05) decreased to 2.4 ± 1.5 D at the final visit. CONCLUSION: Scleral imbrication with vitrectomy and gas tamponade resulted in high reattachment and macular hole closure rates for treating refractory macular hole retinal detachment.

Anterior chamber paracentesis might prevent sustained intraocular pressure elevation after intravitreal injections of ranibizumab for age-related macular degeneration.

BACKGROUND/AIMS: To evaluate the efficacy of anterior chamber paracentesis for preventing sustained intraocular pressure (IOP) elevation after intravitreal ranibizumab (IVR) injections for age-related macular degeneration (AMD). METHODS: The medical records for all cases of exudative AMD treated with IVR injections and followed monthly for 12 months or longer were reviewed retrospectively. Anterior chamber paracentesis was performed just before IVR injections. A sustained IOP elevation was defined as 22 mm Hg or higher during 2 consecutive visits with an increase exceeding 6 mm Hg from baseline. RESULTS: One hundred and eleven eyes met the inclusion criteria, and none of these eyes had a sustained IOP elevation. CONCLUSIONS: Anterior chamber paracentesis before IVR injections may prevent sustained IOP elevations.

[One year outcomes of pars plana vitrectomy in proliferative diabetic retinopathy].

PURPOSE: To evaluate the 1-year results of pars plana vitrectomy for proliferative diabetic retinopathy. PATIENTS AND METHODS: Two hundred thirty six patients with proliferative diabetic retinopathy received primary vitreous surgery at Shiga University of Medical Science Hospital and had at least 1 year follow-up period. The indications for pars plana vitrectomy included vitreous hemorrhage in 140 eyes, extramacular tractional retinal detachment in 60 eyes, macular tractional retinal detachment in 24 eyes and combined tractional retinal detachment in 12 eyes. The visual acuity and changes in visual acuity at 1-year postoperatively were evaluated. Preoperative bevacizumab injection and postoperative visual outcomes were compared between patients treated with 20 gauge (20 G) surgery and with micro incision vitrectomy surgery (MIVS). RESULTS: The visual acuity improved by 3 lines or more in 166 eyes (70%) and remained unchanged in 56 eyes (24%); it decreased by 3 lines or more in 14 eyes (6%). Tractional retinal detachment in MIVS received more bevacizumab injections. MIVS systems achieved better visual results in the combined tractional retinal detachment group than 20 G system. CONCLUSION: Successful visual improvement at 1-year postoperatively was observed in eyes with proliferative diabetic retinopathy after pars plana vitrectomy. Results of this study may suggest the superior performance of MIVS for pars plana vitrectomy in proliferative diabetic retinopathy.

Transscleral drainage to treat peripheral exudative hemorrhagic chorioretinopathy caused by retinal pigment epithelial hemorrhage.

Purpose: To report a case of peripheral exudative hemorrhagic chorioretinopathy with hemorrhagic retinal detachment and subretinal pigment epithelial hemorrhage treated with transscleral subretinal fluid drainage. Observations: The patient was a 70-year-old man with a 15-year history of diabetic retinopathy and age-related macular degeneration. During follow-up, he developed a sudden decrease in visual acuity in the left eye. Corrected visual acuity was 20/32 in the right eye and 20/800 in the left eye, and hemorrhagic retinal detachment and subretinal pigment epithelial hemorrhage were observed in the left eye. Pars plana vitrectomy and transscleral drainage of the subretinal hemorrhage and subretinal pigment epithelial hemorrhage were performed. We initially attempted to displace the subretinal pigment epithelial hemorrhage, but the subretinal hemorrhage was also displaced via a retinal pigment epithelial tear located in the temporal macula. The retina was completely reattached, although visual acuity in the left eye remained at 20/400. Conclusions and Importance: This report describes a surgical technique for hemorrhagic retinal detachment and subretinal pigment epithelial hemorrhage due to peripheral exudative hemorrhagic chorioretinopathy. We believe that transscleral subretinal fluid drainage without intentional retinal tear is a useful and safe method for patients with extensive hemorrhagic retinal detachment.

Comparison of pneumatic displacement for submacular hemorrhages with gas alone and gas plus tissue plasminogen activator.

PURPOSE: To retrospectively evaluate efficacy, safety, and visual outcomes of pneumatic displacement for submacular hemorrhages (SMHs) with or without tissue plasminogen activator (tPA). METHODS: Sixty-eight eyes with fresh SMHs underwent pneumatic displacement. Thirty eyes received intravitreal injection of pure C3F8 gas alone and 38 eyes received gas with tPA (25 µg). The visual analog scale was used to evaluate displacement. The main outcome measures were the visual analog scale score and best-corrected visual acuity 1 month after treatment. The efficacy and safety of tPA were evaluated. RESULTS: The visual analog scale score was 4.9 ± 2.5 in the gas group and 5.9 ± 2.9 in the gas plus tPA group. Sixteen eyes (53.3%) in the gas group and 15 eyes (39.5%) in the gas plus tPA group had best-corrected visual acuity improvements. In the gas group, complications included retinal detachment (n = 1, 3.3%), vitreous opacity (n = 7, 23.3%), and rebleeding (n = 1, 3.3%). In the gas plus tPA group, vitreous opacity (n = 6, 15.8%) was the only complication. Overall, both groups had similar displacement of SMH, visual improvement, and complication rates at 1 month. CONCLUSION: Intravitreal injection of pure C3F8 gas displaced SMHs and improved best-corrected visual acuity in eyes with SMHs. No adjuvant effect or adverse reactions of tPA were found.

Comparison between one injection and three monthly injections of intravitreal bevacizumab for myopic choroidal neovascularization.

AIM: To compare the effects of one intravitreal bevacizumab (IVB) injection with three monthly injections for myopic choroidal neovascularization. METHODS: Group A included 13 patients treated with one IVB injection; group B included 19 patients treated with three monthly 1.25-mg IVB injections. All patients were followed monthly for 12 months with additional injections performed as needed. The best-corrected visual acuity (BCVA) and the central foveal thickness (CFT) on optical coherence tomography were evaluated before and after treatment. RESULTS: The mean logMAR BCVA improved from 0.59 to 0.49 at 12 months in group A (p = 0.21) and from 0.65 to 0.29 in group B (p < 0.001); the improved logMAR BCVA differed significantly between the groups (p < 0.05). The mean CFT decreased from 231 µm at baseline to 150 µm at 12 months in group A (p < 0.05) and from 279 to 156 µm in group B (p < 0.001). During the follow-up, 6 of 13 eyes in group A and 5 of 19 eyes in group B received additional injections. CONCLUSIONS: Treatment starting with three monthly IVB injections may achieve better functional outcomes with fewer retreatments compared with treatment starting with one IVB injection.

Closure of sclerotomies after 25- and 23-gauge transconjunctival sutureless pars plana vitrectomy evaluated by optical coherence tomography.

AIMS: To evaluate sclerotomy closure after 25- and 23-gauge transconjunctival sutureless pars plana vitrectomy using optical coherence tomography (OCT). METHODS: Forty-eight eyes (20 with a macular hole and 28 with an epiretinal membrane) of 47 patients (mean age, 66.5 years) who underwent one of the two procedures were included. Three sclerotomy sites in each eye were measured by cross-sectional OCT images vertical and parallel to the limbus on weeks 1 and 2 and months 1, 2 and 3 postoperatively. RESULTS: After 25-gauge vitrectomy, the scleral wounds evaluated by OCT closed in 40.6% of the eyes at 1 week, 53.3% at 2 weeks, 60.5% at 1 month, 63.6% at 2 months and 63.9% at 3 months. There were significant differences in the closure rates between 1 week and 1 month (p = 0.015), 2 months (p = 0.007) and 3 months (p = 0.006) postoperatively. After 23-gauge vitrectomy, the scleral wounds closed in 31.6% of the eyes at 1 week, 50.0% at 2 weeks, 57.4% at 1 month, 63.0% at 2 months, and 61.1% at 3 months postoperatively. There were significant differences in the closure rates between 1 week and 1 month (p = 0.011), 2 months (p = 0.001) and 3 months (p = 0.002) postoperatively. The wound closure rates did not differ significantly between the two procedures. CONCLUSIONS: Scleral wounds after 25- and 23-gauge transconjunctival sutureless pars plana vitrectomy can be evaluated with OCT. Wound healing seems to be complete 2 weeks postoperatively.

Aqueous vascular endothelial growth factor after intravitreal injection of pegaptanib or ranibizumab in patients with age-related macular degeneration.

PURPOSE: The purpose of this study was to evaluate vascular endothelial growth factor (VEGF) concentrations in the aqueous humor of eyes after intravitreal injections of pegaptanib or ranibizumab in patients with age-related macular degeneration. METHODS: Aqueous humor samples were obtained from 16 eyes with choroidal neo-vascularization secondary to age-related macular degeneration before and after intravitreal injections of pegaptanib (0.3 mg; 5 eyes) and ranibizumab (0.5 mg; 11 eyes). The VEGF concentration was measured using an enzyme-linked immunosorbent assay using a primary antibody against VEGF121 and VEGF165. RESULTS: The VEGF concentrations in the aqueous humor of eyes with age-related macular degeneration ranged from 35.3 pg/mL to 142.4 pg/mL (mean +/- standard deviation, 90.9 pg/mL +/- 40.0 pg/mL) before the injection of pegaptanib and increased significantly, ranging from 298.2 pg/mL to 571.3 pg/mL (mean +/- standard deviation, 452.0 pg/mL +/- 106.4 pg/mL) 6 weeks after the injection (P = 0.005). The VEGF concentrations ranged from 47.2 pg/mL to 307.4 pg/mL (mean +/- standard deviation, 125.9 pg/mL +/- 77.2 pg/mL) before injection of ranibizumab and decreased to <31 pg/mL, the lower limit of detection, 4 weeks after injection. CONCLUSION: The VEGF concentrations in the aqueous humor of eyes with age-related macular degeneration decreased after injections of ranibizumab and increased after injections of pegaptanib.

Interleukin-10 and interleukin-6 in aqueous humor during treatment of vitreoretinal lymphoma with intravitreally injected methotrexate.

OBJECTIVE: To evaluate the effectiveness of measuring anterior chamber interleukin (IL)-10 and IL-6 concentrations during treatment of vitreoretinal lymphoma with intravitreally injected methotrexate. METHODS: Two patients (3 eyes) underwent repeated weekly intravitreal injections of methotrexate (400 microg of methotrexate/50 microl) for 6 weeks. We monitored the IL-10 and IL-6 concentrations in the anterior chamber and the IL-10/IL-6 ratio at baseline and at the last injections using a standard enzyme-linked immunoassay. RESULTS: Repeated intravitreal injections of methotrexate reduced the vitreous opacity. The IL-10/IL-6 ratio decreased consistently in conjunction with clearance of the vitreous opacity in all 3 eyes, from 39.2 to 0.02, 1.67 to 0.03 and 3.05 to 0.159, respectively. CONCLUSIONS: A decrease in the IL-10/IL-6 ratio seems to be related to a decrease in vitreous opacity. Measuring the IL-10/IL-6 ratio in the anterior chamber may be useful to evaluate the effect of treatment of vitreoretinal lymphoma.

Comparison of macular thickness between Cirrus HD-OCT and Stratus OCT.

BACKGROUND AND OBJECTIVE: To compare macular thicknesses in healthy subjects measured with spectral domain optical coherence tomography (SD-OCT) (Cirrus; Carl Zeiss Meditec, Inc., Dublin, CA) with measurements using time domain (TD-OCT) (Stratus; Carl Zeiss Meditec, Inc.). PATIENTS AND METHODS: Macular thickness was measured five times in the same eye of 10 healthy subjects with both Cirrus and Stratus to assess reliability and then once in the same eye of 50 healthy subjects with both Cirrus and Stratus to compare the average obtained by each device. RESULTS: Using TD-OCT, the coefficient of variations (CV) of the macular thicknesses within a 1-mm central area ranged from 0.7% to 3.3% (mean, 1.33%); with SD-OCT, the range was 0.2% to 1.3% (mean, 0.66%). The mean CV with SD-OCT was significantly smaller than with TD-OCT (P < .05). The average macular thicknesses with TD-OCT and SD-OCT were 197.2 +/- 17.8 microm and 257.6 +/- 19.6 microm, respectively. However, the correlation was significant (correlation coefficient, 0.916, P<.001). CONCLUSION: Cirrus showed better reliability than Stratus. Using SD-OCT, the macula was 60-microm thicker than when measured with TD-OCT. Attention should be given to comparing data obtained using different OCT machines.

Vascular endothelial growth factor in aqueous humor before and after intravitreal injection of bevacizumab in eyes with diabetic retinopathy.

OBJECTIVE: To study the concentration of vascular endothelial growth factor in the aqueous humor before and after intravitreal injection of bevacizumab in eyes with proliferative diabetic retinopathy. METHODS: In this prospective, interventional case series, 1.25 mg of bevacizumab was injected into the vitreous cavity as preoperative adjunctive therapy 1 week before pars plana vitrectomy to treat proliferative diabetic retinopathy in 18 eyes in 18 patients. Aqueous humor samples were obtained just before intravitreal injection of bevacizumab and just before vitrectomy 1 week after the injection. Aqueous humor samples also were obtained in patients with cataract without diabetes mellitus (control group). The vascular endothelial growth factor concentration in the aqueous humor was measured using an enzyme-linked immunosorbent assay. RESULTS: Vascular endothelial growth factor concentration in the aqueous humor ranged from 146 to 676 pg/mL (mean +/- SD, 326 +/- 125 pg/mL) before intravitreal injection of bevacizumab and decreased to less than 31 pg/mL (P < .001) in all eyes 1 week after injection. Intravitreal bevacizumab therapy caused no adverse events. The concentrations in the control group ranged from 80 to 218 pg/mL (mean +/- SD, 146 +/- 40 pg/mL). CONCLUSION: Intravitreal injections of bevacizumab resulted in a substantial decrease in vascular endothelial growth factor in the aqueous humor.

Comparison of single injection and three monthly injections of intravitreal bevacizumab for macular edema associated with branch retinal vein occlusion.

PURPOSE: Our aim was to compare the 1 year efficacy and safety results of intravitreal bevacizumab (IVB) in two prospective, consecutive groups of patients with macular edema (ME) following branch retinal vein occlusion (BRVO). PATIENTS AND METHODS: Twenty-five eyes with ME after BRVO received one IVB injection (single-injection group) and 27 eyes received three monthly IVB injections (three-injection group). Both groups were followed monthly for 12 months. The best-corrected visual acuity (BCVA) and the central foveal thickness (CFT) on optical coherence tomography were evaluated before and after treatment. Patients were eligible to receive an IVB injection if the mean CFT increased 100 µm or more or the BCVA decreased 0.1 logarithm of the minimum angle of resolution (logMAR) unit or more compared with values measured on the last visit. RESULTS: The mean logMAR BCVA and CFT, respectively, improved from 0.56 to 0.33 and from 598 µm to 348 µm in the single-injection group (P<0.001) and from 0.55 to 0.26 and from 514 µm to 293 µm in the three-injection group (P<0.001). During the study period, the mean total number of injections was significantly smaller in the single-injection group than in the three-injection group (2.1 and 4.3, respectively, P<0.001). No serious complications related to the IVB injections developed in either group. CONCLUSION: The single-injection group achieved similar visual outcomes for ME secondary to BRVO with fewer injections compared with the three-injection group.