Yoshitsugu Saishin

Effect of vitrectomy on aqueous VEGF concentration and pharmacokinetics of bevacizumab in macaque monkeys.

PURPOSE To evaluate the effect of vitrectomy on the concentration of vascular endothelial growth factor (VEGF) and the pharmacokinetics of intravitreally injected bevacizumab in the aqueous humor in cynomolgus macaques. METHODS Pars plana lensectomy and a standard three-port vitrectomy were performed in one eye each of six macaques. After a minimal 12-week healing period, the vitrectomized eyes received an intravitreal injection of bevacizumab (1.25 mg/50 μL). Aqueous humor and venous blood samples were obtained from the macaques just before vitrectomy, just before injection of bevacizumab, on days 1, 3, and 7, and during weeks 2, 4, 6, and 8 after the injection. The bevacizumab and VEGF concentrations were measured by using enzyme-linked immunosorbent assay. RESULTS The VEGF concentrations in the aqueous humor ranged from 52.6 to 113.9 pg/mL (mean ± standard deviation [SD], 81.7 ± 27.0 pg/mL) before vitrectomy and 20.7 to 72.7 pg/mL (mean ± SD, 51.4 ± 20.5 pg/mL) 3 months after vitrectomy, a difference that reached significance (P = 0.03). The aqueous VEGF concentrations decreased to less than 9.0 pg/mL, the lower limit of detection, in all eyes between 1 and 7 days after injection of bevacizumab. The mean half-life of 1.25 mg intravitreally injected bevacizumab was 1.5 ± 0.6 days (range, 1.0-2.4 days) in the aqueous humor. CONCLUSIONS The VEGF concentration in the aqueous humor decreased and the half-life of the intravitreally injected bevacizumab was shorter in vitrectomized eyes.

Serum and Plasma Vascular Endothelial Growth Factor Concentrations Before and After Intravitreal Injection of Aflibercept or Ranibizumab for Age-Related Macular Degeneration

PURPOSE To evaluate serum and plasma vascular endothelial growth factor (VEGF) concentrations in neovascular age-related macular degeneration patients treated bimonthly with an intravitreal injection of aflibercept or ranibizumab. DESIGN Prospective, interventional case series. METHODS This study includes 17 eyes of 17 patients treated with 2 mg aflibercept (the aflibercept group), 15 eyes of 15 patients treated with 0.5 mg ranibizumab (the ranibizumab group), and 12 patients with cataract (the control group). Serum and plasma VEGF concentrations were quantified using the enzyme-linked immunosorbent assay. RESULTS At baseline, mean serum VEGF concentration (in picograms per milliliter) did not differ significantly among the 3 groups (P = .99). In the aflibercept group, it was 28.3 pg/mL at baseline, decreased to below the detectable limit at 1 week (P < .0001), increased to 11.7 pg/mL at 1 month, which was still significantly less than the baseline level (P < .001), and returned to 23.9 pg/mL (P = .35) at 2 months. In the ranibizumab group, there were no significant differences. At baseline, mean plasma VEGF concentration did not differ significantly among the 3 groups (P = .64). In the aflibercept group, it was 16.2 at baseline, decreased to less than the detectable limit at 1 week (P < .01) and at 1 month (P < .05), and returned to 13.6 pg/mL at 2 months (P = .73). In the ranibizumab group, there were no significant differences. CONCLUSIONS Aflibercept significantly decreased serum and plasma VEGF concentrations 1 month after injection; however, ranibizumab had no significant effect on either serum or plasma VEGF level.

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.

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.

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.

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.

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.

A New Biconcave Contact Lens for Vitrectomy in Eyes With Intraocular Lens Implantation

The authors report a new biconcave contact lens capable of providing superior surgical views of eyes during vitrectomy and intraocular lens implantation under both fluid-filled and air-filled conditions. The new biconcave lens is made of a glass with a high refractive index (nd = 1.883). The lens is placed on the cornea using a regular lens ring for the floating vitrectomy lens system. During vitrectomy, the new biconcave lens provides a view as clear as that of the commercially available flat-concave lens when the vitreous cavity is filled with fluid. The lens also provides a more magnified view than the commercially sold biconcave lens during fluid-air exchange, with no need for replacement. The new biconcave vitrectomy lens spares the surgeon the trouble of replacing different refractive lenses during the fluid-air exchange procedure in an eye undergoing intraocular lens implantation, and may be helpful for vitreous surgery.

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

Clinical evidence supports the efficacy of bimonthly aflibercept injection for age‐related macular degeneration.

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.