ABSTRACT
PURPOSE: To analyze the surgical outcomes and complication rates in a group of patients with refractory glaucoma who underwent simultaneous pars plana vitrectomy (PPV) and PC7 or PC8 Ahmed glaucoma valve (AGV) implantation. METHODS: Retrospective case series study of 10 eyes in 9 patients with secondary glaucoma, refractory to other treatment, who underwent 23G-PPV and implantation of PC7 or PC8 AGV between 2012 and 2014. Study variables were postoperative BCVA, IOP and the number of glaucoma medications, which were evaluated preoperatively and at 1â¯day, 1â¯week and 1, 3, 6, and 12â¯months after the surgical intervention. Absolute success was defined as IOP less than 21â¯mmHg in the absence of any medication and qualified success if medication was needed to control IOP under 21â¯mmHg. RESULTS: The average follow-up was 10.2⯱â¯2.89â¯months. Postoperative IOP levels decreased in all cases in comparison with preoperative values (pâ¯<â¯0.05). Absolute success rate was 60%, reaching 100% in terms of qualified success. Kaplan-Meier survival analysis showed 60% absolute success at 12â¯months. Changes in postoperative BCVA were not statistically significant in comparison with preoperative data. Early postoperative complications were athalamia, hyphema, and retinal detachment; late complications were pars plana clip extrusion and cystic bleb. CONCLUSIONS: PC7 and PC8 Ahmed valve implantation via pars plana is a safe and useful option in patients with secondary refractory glaucoma who are either candidates for PPV or have been previously vitrectomized.
ABSTRACT
OBJECTIVES: To identify and analyze the phosphate concentration in glaucoma eye drops available in Spain. MATERIAL AND METHODS: Glaucoma medications containing phosphates were identified according to the 2013 Vademecum and the website of the Spanish Agency for Medicines and Medical Devices. Phosphate concentration was determined in these eye drops using ultraviolet molecular absorption spectrophotometry, and pH was determined using scan image analysis algorithms of pH strips. RESULTS: A total of 37 phosphate containing glaucoma eye drops were identified. The mean phosphate concentration was 97.72±75.52mM. The group with higher concentration of active substance was timolol (204.85±42.38mM) followed by brimonidine/timolol (200.9mM). No statistically significant difference was found between brand name (95.65±71.11mM) and generic eye drops (99.14±80mM, P=.892). Although no statistically significant difference was found between products containing preservatives (99.24±76.78mM) and those without preservatives (85.17±72.86mM) (P=.730), a lower phosphate concentration was observed in the preservative-free Timolol and Latanoprost. Single dose samples showed a lower phosphate concentration than multi-dose ones (102.04±75.39 vs. 22.24±2.98mM, P<.001). The mean pH was 7.13±0.63. No statistical correlation was found between phosphate concentration and pH (r: 0.07). CONCLUSION: The phosphate concentration in glaucoma eye drops exceeded the tear film physiological level (1.45mM). No difference was observed between brand names and generic eye drops. Lower phosphate concentration was observed in preservative-free single dose eye drops.
Subject(s)
Glaucoma/drug therapy , Ophthalmic Solutions/chemistry , Phosphates/analysis , Brimonidine Tartrate/analysis , Buffers , Drugs, Generic/chemistry , Humans , Hydrogen-Ion Concentration , Latanoprost , Preservatives, Pharmaceutical/analysis , Prostaglandins F, Synthetic/analysis , Spain , Spectrophotometry, Ultraviolet , Timolol/analysisABSTRACT
OBJECTIVE: To determine phosphate concentration and pH in artificial tear eye drops commercially available in Spain. MATERIALS AND METHODS: A total of 71 examples of artificial tear preparations were identified in a search of Vademecum 2014 and the Spanish Medicines Agency website. In the 24 artificial tear products containing phosphates, quantification of these was performed by ultraviolet molecular absorption spectrophotometry, and the determination of pH was performed using scan image analysis algorithms of pH strips. RESULTS: Of the 71 artificial tears tested, 24 contained phosphate among their excipients in the data sheet, three of which had a concentration level below detection limit (<0.1mM). The mean phosphate concentration was 17.91±23.87mM. The artificial tear sample containing a higher concentration was Colircusi Humectante (87.1mM). Lubricants based on hypromellose showed the highest phosphate concentration (41.59±32.1mM), showing statistically significant differences compared to povidone (P=.0196) and hyaluronate (P=.0067). Statistically significant differences were found between products containing preservatives (32.39±20.91mM), and preservative free ones (8.49±11.98mM) (P=.0498). However, no difference was found between multidose (20.21±26.91mM) and unidose (9.31±14.39mM) samples, or between brand name (15.44±23.3mM) and generic eye drops (20.81mM). The mean pH was 6.93±0.26 (6.2-7.22). No statistical correlation was detected between phosphate concentration and pH (Spearman's Rho -0.1089 and P=.6125). CONCLUSION: A total of 24 (33.8%) of the 71 artificial tears contained phosphate. We believe identifying the phosphate concentration of artificial tears is useful information in order to avoid complications in high-risk patients.