Background: Laser photocoagulation restricted to ablation of the avascular retina has been the conventional but not a completely effective treatment strategy in the management of threshold retinopathy of prematurity (ROP). The purpose of this study was to compare the structural outcomes of additional posterior to ridge diode laser compared to conventional diode laser to avascular retina alone in threshold stage III ROP.

Methods: This was a prospective, randomized study involving infants diagnosed with threshold stage III ROP in one or both the eyes. The infants were randomized into control and study groups. Infants under the control group underwent conventional laser to avascular retina alone while infants under the study group received additional two rows of laser posterior to the ridge in the vascular retina. The infants were followed up at 2 weeks, 1 month and up to 6 months after the laser procedure.

Results: During the study period of 1 year, 42 eyes of 24 infants were recruited into this study with 21 eyes in each group. The mean birth weight was 1,310.48±400.92 g in the test group and 1,341.9±396.2 g in the control group. The mean post conceptional age at the time of intervention was 36.43±2.79 weeks in test group and 36.29±2.55 weeks in the control group. At 1-month post laser, 19 eyes in the study group showed regression of neovascularization laser compared to 18 eyes in the control group. However at the end of 3 and 6 months post laser, both groups had showed similar rates regression of neovascularization (19 of 21 eyes in both groups). Five eyes in the study group and six in the control group required additional laser treatment. Two eyes in the study group and one eye in the control group developed post laser vitreous hemorrhage.

Conclusions: Posterior to ridge laser treatment for severe stage 3 ROP did not show any additional benefit compared to conventional laser.

Background: Laser photocoagulation restricted to ablation of the avascular retina has been the conventional but not a completely effective treatment strategy in the management of threshold retinopathy of prematurity (ROP). The purpose of this study was to compare the structural outcomes of additional posterior to ridge diode laser compared to conventional diode laser to avascular retina alone in threshold stage III ROP.

Methods: This was a prospective, randomized study involving infants diagnosed with threshold stage III ROP in one or both the eyes. The infants were randomized into control and study groups. Infants under the control group underwent conventional laser to avascular retina alone while infants under the study group received additional two rows of laser posterior to the ridge in the vascular retina. The infants were followed up at 2 weeks, 1 month and up to 6 months after the laser procedure.

Results: During the study period of 1 year, 42 eyes of 24 infants were recruited into this study with 21 eyes in each group. The mean birth weight was 1,310.48±400.92 g in the test group and 1,341.9±396.2 g in the control group. The mean post conceptional age at the time of intervention was 36.43±2.79 weeks in test group and 36.29±2.55 weeks in the control group. At 1-month post laser, 19 eyes in the study group showed regression of neovascularization laser compared to 18 eyes in the control group. However at the end of 3 and 6 months post laser, both groups had showed similar rates regression of neovascularization (19 of 21 eyes in both groups). Five eyes in the study group and six in the control group required additional laser treatment. Two eyes in the study group and one eye in the control group developed post laser vitreous hemorrhage.

Conclusions: Posterior to ridge laser treatment for severe stage 3 ROP did not show any additional benefit compared to conventional laser.

Background: To settle the fundamentals of a numerical procedure that relates retinal ganglion-cell density and threshold sensitivity in the visual field. The sensitivity of a generated retina and visual pathways to virtual stimuli are simulated, and the conditions required to reproduce glaucoma-type defects both in the optic-nerve head (ONH) and visual fields are explored.

Methods: A definition of selected structural elements of the optic pathways is a requisite to a translation of clinical knowledge to computer programs for visual field exploration. The program is able to generate a database of normalized visual fields. The relationship between the number of extant receptive fields and threshold sensitivity is plotted for background sensitivity and corresponding automated perimetry. A solution in two planes to the 3D distribution of axons in the ONH is proposed. Visual fields with induced damage in the optic disc are comparable in pattern and quantity to glaucomatous records.

Results: The two-level simulation of the ONH facilitates the analysis of optic-cup/retinal defects. We can generate the virtual optic pathways tailored to the age and morphology of the patient’s eye, and it is possible to reproduce glaucomatous damage by “reverse engineering” engineering. The virtual cortical model renders a quantitative relationship between visual defect and neural damage.

Conclusions: A two-level computing of the retina/optic nerve facilitates the analysis of neuroretinal defects and can be incorporated to automatic perimeters to facilitate visual field analysis.

Background: To settle the fundamentals of a numerical procedure that relates retinal ganglion-cell density and threshold sensitivity in the visual field. The sensitivity of a generated retina and visual pathways to virtual stimuli are simulated, and the conditions required to reproduce glaucoma-type defects both in the optic-nerve head (ONH) and visual fields are explored.

Methods: A definition of selected structural elements of the optic pathways is a requisite to a translation of clinical knowledge to computer programs for visual field exploration. The program is able to generate a database of normalized visual fields. The relationship between the number of extant receptive fields and threshold sensitivity is plotted for background sensitivity and corresponding automated perimetry. A solution in two planes to the 3D distribution of axons in the ONH is proposed. Visual fields with induced damage in the optic disc are comparable in pattern and quantity to glaucomatous records.

Results: The two-level simulation of the ONH facilitates the analysis of optic-cup/retinal defects. We can generate the virtual optic pathways tailored to the age and morphology of the patient’s eye, and it is possible to reproduce glaucomatous damage by “reverse engineering” engineering. The virtual cortical model renders a quantitative relationship between visual defect and neural damage.

Conclusions: A two-level computing of the retina/optic nerve facilitates the analysis of neuroretinal defects and can be incorporated to automatic perimeters to facilitate visual field analysis.

Abstract: This article reviews the history of the femtosecond laser in ophthalmology and its subsequent introduction into the field of cataract surgery. It discusses the innovations that this technology has brought to the field. The article also describes the current system of teaching cataract surgery to ophthalmology residents in the United States and then examines how femtosecond laser-assisted cataract surgery (FLACS) can be a beneficial part of residency education.

Abstract: This article reviews the history of the femtosecond laser in ophthalmology and its subsequent introduction into the field of cataract surgery. It discusses the innovations that this technology has brought to the field. The article also describes the current system of teaching cataract surgery to ophthalmology residents in the United States and then examines how femtosecond laser-assisted cataract surgery (FLACS) can be a beneficial part of residency education.

Background: To compare objective electrophysiological contrast sensitivity function (CSF) in patients implanted with either multifocal intraocular lenses (MIOLs) or monofocal intraocular lenses (IOLs) by pattern reversal visual evoked potentials (prVEP) measurements.

Methods: Fourty-five cataract patients were randomly allocated to receive bilaterally: apodized diffractive-refractive Alcon Acrysof MIOL (A), full diffractive AMO Tecnis MIOL (B) or monofocal Alcon Acrysof IOL (C). Primary outcomes: 1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies. Secondary outcomes: psychophysical CSF measured with VCTS-6500, photopic uncorrected distance (UDVA), and mesopic and photopic uncorrected near and intermediate visual acuities (UNVA and UIVA respectively).

Results: Electrophysiological CSF curve had an inverted U-shaped morphology in all groups, with a biphasic pattern in Group B. Group A showed a lower CSF than group B at 4 and 8 cpd, and a lower value than group C at 8 cpd. Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B. Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups. Mesopic UNVA and UIVA were better in group B.

Conclusions: Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs. This may be related to the visual acuity under certain conditions or to IOL characteristics. This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision.

Background: To compare objective electrophysiological contrast sensitivity function (CSF) in patients implanted with either multifocal intraocular lenses (MIOLs) or monofocal intraocular lenses (IOLs) by pattern reversal visual evoked potentials (prVEP) measurements.

Methods: Fourty-five cataract patients were randomly allocated to receive bilaterally: apodized diffractive-refractive Alcon Acrysof MIOL (A), full diffractive AMO Tecnis MIOL (B) or monofocal Alcon Acrysof IOL (C). Primary outcomes: 1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies. Secondary outcomes: psychophysical CSF measured with VCTS-6500, photopic uncorrected distance (UDVA), and mesopic and photopic uncorrected near and intermediate visual acuities (UNVA and UIVA respectively).

Results: Electrophysiological CSF curve had an inverted U-shaped morphology in all groups, with a biphasic pattern in Group B. Group A showed a lower CSF than group B at 4 and 8 cpd, and a lower value than group C at 8 cpd. Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B. Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups. Mesopic UNVA and UIVA were better in group B.

Conclusions: Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs. This may be related to the visual acuity under certain conditions or to IOL characteristics. This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision.