Potential effects of angiogenesis-related factors on the severity of APAC and surgical outcomes of trabeculectomy.

BACKGROUND: EPO (erythropoietin) and PDGF (platelet derived growth factor) families are thought to be associated with angiogenesis under hypoxic condition. The sharp rise of intraocular pressure in acute primary angle closure (APAC) results in an inefficient supply of oxygen and nutrients. We aimed to measure the expression of EPO and PDGF family members in APAC eyes and demonstrate their associations with APAC's surgical success rate. METHODS: Concentrations of EPO, PDGF-AA, -BB, -CC and -DD collected in aqueous humor samples of 55 patients recruited were measured. Before operations, correlations between target proteins and IOP (intraocular pressure) were detected between APAC (acute primary angle closure) and cataract patients. Based on the post-operative follow-up, the effects of EPO and PDGF family members on the successful rate of trabeculectomy were tested. RESULTS: The levels of EPO, PDGF-CC and -DD were significantly elevated in the APAC group compared to the cataract group. During the post-operative follow-up, EPO, PDGF-CC and -DD showed significant differences between the success and failure groups. In multivariable linear regression analyses, failed filtration surgery was more likely in APAC eyes with higher EPO level. The Kaplan-Meier survival plot suggested that the success rate in eyes with low EPO level was significantly higher than that in eyes with high EPO level. CONCLUSION: The levels of EPO, PDGF-CC and -DD were significantly elevated in failure group. EPO level correlated with preoperative IOP and numbers of eyedrops, and higher EPO level in aqueous humor is a risk factor for trabeculectomy failure. It can be a biomarker to estimate the severity of APAC and the success rate of surgery. The investigation of mechanism of EPO in APAC a may have potential clinical applications for the surgical treatment of APAC.

[The efficacy of low-energy selective laser trabeculoplasty].

OBJECTIVE: To evaluate the efficacy of low-energy selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT) following up to one year. METHODS: In this prospective clinical study, seventy-four eyes of seventy-four patients with OHT and POAG were enrolled. Thirty-nine patients received low-energy treatment using half of conventional laser energy and 100 spots over 360° of the trabecular meshwork, while thirty-five patients received conventional laser energy as control. Intraocular pressure (IOP) and complications including conjunctival hyperemia and anterior uveitis were followed up at week 2, and month 1, 3, 6, and 12. Effective rate (reduction of IOP ≥ 20%) of treatment between the two groups and total rate of complications were analyzed by the chi-squared test. RESULTS: In OHT group, the effective rates of treatment were 81.81(9/11), 63.63 (7/11), 63.63 (7/11), 63.63 (7/11), and 45.45% (5/11) in the low-energy group and 50.00 (5/10), 70.0 (7/10), 60.0 (6/10), 40.0 (4/10), and 50.0% (5/10) in the control group, at weeks 2, month 1, 3, 6, and 12 after treatment respectively, while in POAG, the effective rates were 83.33 (15/18), 88.88 (16/18), 72.22 (13/18), 66.66 (12/18), and 44.44% (8/18) in the low-energy group and 84.21 (16/19), 73.68 (14/14), 57.89 (11/19), 57.89 (11/19) and 47.37% (9/19) in the control group at weeks 2, month 1, 3, 6, and 12 after treatment, respectively. There were no statistical difference between the low energy and conventional energy group at all time points in OHT (χ(2) = 2.386, 0.096, 1.173, 1.110, 0.043) and POAG (χ(2) = 0.005, 1.393, 0.833, 0.302, 0.032) group (P > 0.05). Complications were significantly (χ(2) = 4.299, P < 0.05) different between the two groups (eight eyes in the low-energy group on the day of treatment and fifteen eyes in the control group). Transient IOP spike (≥ 3 mm Hg, 1 mm Hg = 0.133 kPa) occurred in three eyes (in the control group) on the day of treatment and partial peripheral anterior synechiae in one eye (in the control group) one month after treatment. CONCLUSIONS: Low-energy SLT is as effective in lowering IOP with less complications compared with conventional laser energy SLT, which can be considered as an option for glaucoma therapy.

The efficacy of low-energy selective laser trabeculoplasty.

BACKGROUND AND OBJECTIVE: to analyze the efficacy of low-energy selective laser trabeculoplasty (SLT) in patients. PATIENTS AND METHODS: in 74 patients (74 eyes) with ocular hypertension, suspected glaucoma, or primary open-angle glaucoma, SLT was the first-choice treatment. Thirty-nine patients in the low-energy group received treatment using half of conventional laser energy over 360° of the trabecular meshwork (at 100 points). Thirty-five patients in the control group received conventional laser energy. Patients were observed for 1 year. Complications and intraocular pressure (IOP) were observed. RESULTS: postoperative transient IOP spike (≥ 3 mm Hg) occurred in three eyes on the day of treatment and partial peripheral anterior synechiae occurred in one eye 1 month after treatment only in the control group. Effective rates of treatment (≥ 20% IOP reduction) at week 2 and month 1, 3, 6, and 12 after treatment were 69.23%, 64.10%, 61.54%, 53.85%, and 48.72% in the low-energy group and 71.43%, 71.43%, 60%, 51.43%, and 48.57% in the control group, respectively. There was no statistically significant difference between the two groups at various time points (P = .836, .501, .892, .835, .990). CONCLUSION: compared with SLT using conventional laser energy, low-energy SLT lowers IOP with fewer complications, making it a safe and effective option.