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Hugo Quiroz-Mercado, 1 Ehud Ivri, 2 Roberto Gonzalez-Salinas, 1 Iraklis C Kourtis, 2 Joseph Gilbert, 2 José Francisco Pérez-Vázquez, 1 Mark Blumenkranz, 2 Jesús Jiménez-Román, 1 George Marcellino 2 1Association to Prevent Blindness, Hospital Sanchez-Bulnes, Mexico City, Mexico; 2Kedalion Therapeutics Inc., Menlo Park, CA, USACorrespondence: Hugo Quiroz-Mercado Vicente García Torres #46, Coyoacan, CDMX CP 04330, MexicoTel/Fax +52-5-10841-400Email hugoquiroz@yahoo.comPurpose: Self-administration of topical ophthalmic therapies remains challenging for many patients as errors due to improper technique are common. The aim of the current studies was to evaluate a novel electromechanical topical ocular drug delivery device designed to facilitate precise dosing and accurate delivery with substantially lower drug exposure than conventional eye drops.Patients and Methods: Two randomized Phase 1 studies were performed to evaluate the efficacy and safety of a single dose of a topical ophthalmic solution administered as a ∼ 9 μL microfluid stream via the test device compared with a ∼ 30– 40 μL drop delivered via conventional dropper in healthy subjects (Trial 1) and glaucoma patients (Trial 2). In Trial 1, a 1% tropicamide/2.5% phenylephrine solution was administered via the test device in one eye and by conventional dropper in the contralateral eye. Pupil dilation was measured at 30min intervals post-instillation and subject comfort was assessed using a visual analogue scale (range, 0– 100). In Trial 2, patients were randomized to receive latanoprost 0.005% via the test device or conventional dropper. Intraocular pressure was measured at baseline and 4– 8hrs post-instillation.Results: In Trial 1 (N=20), mean (SD) pupil diameter 30mins post-instillation increased by 3.4 (0.9) and 3.5 (1.0) mm in the test and control eyes, respectively. The mean comfort score was 81.7 for the test device versus 57.3 for conventional dropper delivery. In Trial 2 (N=18), the mean change in intraocular pressure following administration of latanoprost was – 5.0 (1.8) and – 4.3 (3.3) mm Hg in the test and control groups, respectively. No serious adverse events were observed in either study.Conclusion: Administration of a single dose of topical ophthalmic therapy via an electromechanical drug delivery device resulted in comparable effects on pupil dilation and intraocular pressure with lower drug exposure and increased patient comfort compared with conventional dropper delivery.Keywords: mydriasis, phenylephrine, tropicamide, glaucoma, intraocular pressure, latanoprost, topical ocular drug delivery, safety

Guillermo Salcedo-Villanueva,1 Manuel Trujillo-Alvarez,1 Catalina Becerra-Revollo,2 Estefanía Ibarra-Elizalde,2 Mariana Mayorquín-Ruiz,2 Raul Velez-Montoya,1 Gerardo García-Aguirre,1 Roberto Gonzalez-Salinas,3 Virgilio Morales-Cantón,1 Hugo Quiroz-Mercado,1 Eduardo Moragrega-Adame2 1Retina Department, Asociación Para Evitar La Ceguera En México, Mexico City, Mexico; 2Ocular Ultrasound Department, Asociación Para Evitar La Ceguera En México, Mexico City, Mexico; 3Research Department, Asociación Para Evitar La Ceguera En México, Mexico City, MexicoCorrespondence: Guillermo Salcedo-VillanuevaRetina Department, Asociación Para Evitar La Ceguera En México, Vicente García Torres #46. Col. San Lucas, Coyoacán, Mexico City 04030, MexicoEmail guillermo.salcedo@apec.com.mxPurpose: To propose a method for quantification of vitreous hemorrhages (VH) termed minimum image gain (MIG). Therefore, to obtain MIG measurements in patients with VH and to compare them to normal controls; to compare results between graders; and to obtain and compare MIG from two different ultrasound systems.Methods: Retrospective and cross-sectional, observational, and comparative study performed in two parts: Part 1) Retrospective comparison of MIG in VH vs controls by two experienced graders, with intra/inter-observer variability: MIG technique is described. MIG is performed retrospectively in two groups, VH patients and normal controls. Groups are compared with independent samples t-test. Intra- and interobserver variability between graders was obtained. Part 2) Cross-sectional analysis of variability from nonexperienced graders and with different ultrasound systems: MIG is performed in cross-sectional measurements of VH patients, by two unexperienced graders, and with two ultrasound systems. Interobserver variability and Bland–Altman plot with levels of agreement (LoA) were obtained.Results: Part 1: 50 patients with VH resulted in mean MIG: 52.8 dB; 34 controls resulted in mean MIG: 77.97 dB. Independent samples t-test resulted in a statistical significant difference. Intra- and inter-observer variability resulted in an almost perfect agreement between experienced graders. Part 2: 63 patients with VH, mean MIG: 56.19 dB. Inter-observer variability resulted in a very high agreement between unexperienced observers. LoA resulted in a statistical difference between the two ultrasound systems.Conclusion: MIG may provide an objective and reproducible way to quantify vitreous hemorrhage density and potentially any vitreous humor opacity. Agreement is high even with unexperienced graders. However, the two ultrasound systems analyzed may not be interchangeable.Keywords: diagnostic imaging, retina, ultrasonography, vitreous hemorrhage, vitreous humor &nbsp

Age-related macular degeneration (AMD) is a well-characterized and extensively studied disease. It is currently considered the leading cause of visual disability among patients over 60 years. The hallmark of early AMD is the formation of drusen, pigmentary changes at the macula, and mild to moderate vision loss. There are two forms of AMD: the “dry” and the “wet” form that is less frequent but is responsible for 90% of acute blindness due to AMD. Risk factors have been associated with AMD progression, and they are taking relevance to understand how AMD develops: (1) advanced age and the exposition to environmental factors inducing high levels of oxidative stress damaging the macula and (2) this damage, which causes inflammation inducing a vicious cycle, altogether causing central vision loss. There is neither a cure nor treatment to prevent AMD. However, there are some treatments available for the wet form of AMD. This article will review some molecular and cellular mechanisms associated with the onset of AMD focusing on feasible treatments for each related factor in the development of this pathology such as vascular endothelial growth factor, oxidative stress, failure of the clearance of proteins and organelles, and glial cell dysfunction in AMD.