Purpose: To evaluate the clinical effect of 5-μm pore filter connected with three-way cock by removing the vehicle in triamcinolone acetonide (TA) suspension.Methods: Through 5-μm pore filter connected with three-way cock, TA suspension was replaced by intraocular irrigating solution. The new suspension has been applied to 60 cases of diabetic branch retinal vein occlusion, diabetic macular edema and agerelated macular degeneration patients through intravitreal injection. It was also been applied to 41 cases of diabetic retinopathy, epimacular membrane, proliferative vitreoretinopathy and idiopathic macular hole patients to assist pas plana vitrectomy (PPV). Whether TA particles can adhere to posterior hyaloid cortex, epiretinal membrane and internal limiting membrane during the surgery have been observed.During follow up, corrected visual acuity and intraocular pressure were recorded.Results: Fiveμm pore filter connected with three-way cock can remove the vehicle in TA suspension successfully and retain TA particles. When the new suspension was applied to assist PPV, it can adhere to posterior hyaloid cortex, epiretinal membrane, internal limiting membrane and visualized them clearly. In all the 41 cases that underwent PPV surgery, visual acuity of 30 cases increased or remained stable.Intraocular hypertension happened in 4 cases. Two cases of the 41 patients had cataract formation during follow up. In the 60 cases that underwent TA intravitreal injection,45 cases increased their visual acuity at least 2 lines. Intraocular hypertension happened in 17 cases and 4 patients had cataract formation. None of the 101 patients caught endophthalmitis or other serious complications.Conclusion: Filter connected with three-way cock can remove the vehicle in TA suspension effectively and this procedure can be applied to intravitreal injection or PPV. This manipulation is so simple that it deserves to be popularized for clinical use.

Study of the Influence of Angiostatin Intravitreal Injection on Vascular Leakage in Retina and Iris of the Experimental Diabetic Rats

Purpose: To examine the effect of an intravitreal injection of angiostatin on vascular leakage in retina and iris of the diabetes and study its possible mechanism.Methods: Experimental diabetes was induced in 24 rats by an intravenous injection of streptozotocin (STZ) during 48 adult rats. Three groups were randomization distributed of them. There were 8 of both normal and diabetic rats in each group. STZ-diabetic rats and age-matched normal rats received an intravitreal injection of 5 μl of sterile PBS (Phosphate Buffered Saline) into the right eye, and the left eye was non-injected in the group A; Angiostatin was injected into the vitreous of the right eye (7.5 μg/5μl/eye), and the left eye received the same volume of sterile PBS as the control in the group B and C. The vascular permeability of retina and iris was measured using the Evans blue method at 2 days following the injection in the group A and B. Expres sion of VEGF in retina was evaluated using western blot analysis 24 hours following the injection in the group C.Results: Diabetic rats showed significant increases of vascular permeability in the retina (P＜0.01) and iris (P＜0.05). Angiostatin-injected eyes showed significant decreases in vascular permeability in the retina (P＜0.01) and iris (P＜0.05) comparing with the PBS-injected eyes in STZ-diabetic rats. In contrast, intravitreal injection of the same dose of angiostatin into the age-matched normal rats did not result in any significant reduction in vascular permeability in the retina and iris, when compared with the contralateral eye with PBS injection (P＞0.05). Angiostatin injection significantly reduced VEGF level in the retinas of STZ-diabetic rats but did not affect retinal VEGF level in normal rats.Conclusions: Angiostatin significantly reduce pathological vascular permeability in the retina and iris of STZ-diabetic rats but not in normal rats. Angiostatin down-regulates VEGF expression and thus, blocks the major cause of vascular leakage in the diabetic retina. Therefore, angiostatin may have a therapeutic potential in the treatment of diabetic macular edema, cystoid macular edema, uvietis and other diseases with vascular leakage.

Background:To compare the structural outcome of intravitreal bevacizumab (IVB) and laser treatment for type 1 retinopathy of prematurity (ROP). Methods: This is a retrospective comparative study. From December 2002 to April 2009, patients with type 1 ROP according to criteria of Early Treatment of Retinopathy of Prematurity (ETROP) study were treated by peripheral retinal diode laser photocoagulation in nearly confluent pattern. From May 2009 to January 2015, we performed IVB for patients with type 1 ROP. The patients were closely followed until disappearance of retinal neovascularization in the laser group and regression of avascular zone in the bevacizumab group. The demographical data, postmenstrual age (PMA) for treatment, and fundus ifndings were recorded by chart review. The difference between laser and bevacizumab groups was compared by Studentt-test and Fisher exact test. Results: We collected 43 patients (86 eyes) with type 1 ROP, including 30 male and 13 female infants. Their mean gestation age and birth body weight (BBW) were 27.5 weeks and 1,034 gm. Zone I and zone II disease were found in 8 and 35 patients. The mean PMA for treatment was 37.3 weeks. The mean follow-up period was 54.4 months. Laser treatment was administered in 26 patients, and bevacizumab injection for 17 infants. Single session of laser was performed in all patients of laser group without recurrence of retinal neovascularization. Complete regression of ROP was found in 15 infants of bevacizumab group following the ifrst IVB. Four eyes in two patients (2/17, 11.7%) had recurrence of ROP and received additional injections and adjuvant laser treatment. There was no unfavorable anatomical results such as retinal detachment or macular ectopia or complications such as cataract or endophthalmitis in either bevacizumab or laser management. Conclusions: Laser therapy and IVB were both effective treatments for type 1 ROP to cause favorable anatomical outcomes. Single session of laser ablation in nearly conlfuent pattern was sufifcient for complete regression of ROP in laser group. Single IVB was appropriate for managing most of cases with ROP in bevacizumab group, but a small proportion (nearly one tenth) of them had recurrent episodes requiring adjuvant therapies.

Purpose:To study the effect of intravitreal injections of triamcinolone acetonide (TA) for the treatment of macular edema secondary to central retinal vein occlusion (CRVO)in a sample of Chinese patients from Shaanxi province.Methods:The 50 eyes from 50 patients were separated into three TA treatment groups:17 patients were given 4 mg/0.1ml,19 patients were given 8 mg/0.2 ml,and 14 patients were given 16 mg/0.4 ml.Patients were followed up for 12 months.Foveal thickness,intraocular pressure (IOP),and best-corrected visual acuity (BCVA) were measured.Results:Macular edema responded well both anatomically and functionally to the TA injections.After the initial intravitreal injection,macular edema recurred at 2-4 months in the low-dose group (4 mg),at 3-5 months in the medium-dose group (8 mg),and at 6-9 months in the high-dose group (16 mg).No significant difference in BCVA or in foveal thickness were observed between the first intravitreal injection and the re-injection.There was no increase in IOP after re-injection of 16 mg TA,if the patient did not have an elevated IOP after the initial intravitreal injection of 4/8 mg TA.Conclusion:A low dosage of TA (4 mg) administered via intravitreal injection might be useful as an initial treatment for macular edema secondary to CRVO.A higher dosage of TA (16mg) can be used if there is no IOP elevation with the initial TA injection.