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1.
Invest Ophthalmol Vis Sci ; 53(11): 6973-80, 2012 Oct 09.
Article in English | MEDLINE | ID: mdl-22969069

ABSTRACT

PURPOSE: To evaluate macular function in patients with open-angle glaucoma (OAG) by means of multifocal electroretinogram (mfERG). METHODS: Twenty-four OAG patients (mean age 54.6 ± 9.1 years) and 14 age-similar controls were enrolled. OAG patients had intraocular pressure (IOP) less than 18 mm Hg with topical medical treatment, 24-2 visual field (Humphrey Field Analyzer [HFA]) with mean deviation (MD) between -2 and -12 dB, and corrected pattern standard deviation (CPSD) between +2 and +10 dB and no history or presence of cataract and/or macular disease. MfERGs in response to 61 M-stimuli presented to the central 20° of the visual field were assessed in OAG patients (24 eyes) and in controls (14 eyes). Ring (R) analysis was performed every five retinal eccentricities in areas between the fovea and midperiphery: 0° to 2.5° (R1), 2.5° to 5° (R2), 5° to 10° (R3), 10° to 15° (R4), and 15° to 20° (R5). MfERG response amplitude density of the N1-P1 components (N1-P1 RAD, nV/deg(2)) and P1 implicit time (P1 IT, ms) of the first-order binary kernel were measured for each ring. RESULTS: OAG patients showed a significant (P < 0.01) decrease in N1-P1 RADs and an increase in P1 IT in both R1 and R2 with respect to controls. The reduction in N1-P1 RADs was significantly (P < 0.01) correlated with HFA MD and CPSD. No other significant differences between OAG and controls were found. CONCLUSIONS: OAG patients show macular dysfunction detectable by the mfERG technique. Since the mfERG N1-P1 component is thought to be generated by preganglionic elements (photoreceptors and OFF bipolar cells), our data support the functional impairment of the neural generators of the macular region in patients with glaucoma.


Subject(s)
Electroretinography , Glaucoma, Open-Angle/physiopathology , Macula Lutea/physiology , Retinal Diseases/physiopathology , Adult , Aged , Humans , Intraocular Pressure/physiology , Middle Aged , Visual Field Tests , Visual Fields
2.
Clin Neurophysiol ; 121(3): 380-5, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20071230

ABSTRACT

OBJECTIVE: To determine the impact of the regional retinal responses on cortical visually evoked responses, by evaluating the relationship between multifocal ERG (mfERG) and multifocal VEP (mfVEP), in the retinitis pigmentosa (RP) model. METHODS: MfERGs and mfVEPs were recorded from 20 typical RP patients. Response amplitude density (RAD, nV/deg(2)) and implicit time (ms) of the mfERG 1st order binary kernel (N1-P1) and mfVEP 2nd order binary kernel (P1) components were measured. Ring analysis, matched for mfERG and mfVEP stimuli, was performed between fovea and mid-periphery (0-2.5, 2.5-5, 5-10, 10-15 and 15-20deg). RESULTS: At central and pericentral retinal regions (four eccentricities between 0 and 15deg), mfERG N1 RADs were positively correlated (r0.68, p<0.01) with corresponding mfVEP P1 RADs. Similarly, mfERG P1 implicit times were positively correlated (r>or=0.65, p<0.01) with corresponding mfVEP N1 implicit times. CONCLUSIONS: There are quantitative correlations between mfERG and mfVEP components in RP. SIGNIFICANCE: The data suggest that regional responses of the photoreceptors and off-bipolar cells, the main generators of mfERG N1, have a major impact on the corresponding cortical activity.


Subject(s)
Evoked Potentials, Visual/physiology , Neuronal Plasticity/physiology , Retina/physiopathology , Retinitis Pigmentosa/physiopathology , Visual Cortex/physiopathology , Visual Pathways/physiopathology , Adolescent , Adult , Electroencephalography , Electroretinography , Female , Humans , Male , Middle Aged , Neural Pathways/physiopathology , Photoreceptor Cells, Vertebrate/pathology , Retinal Bipolar Cells/physiology , Retinal Ganglion Cells/physiology , Young Adult
3.
Ophthalmology ; 115(2): 324-333.e2, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17716735

ABSTRACT

OBJECTIVE: To evaluate the influence of short-term carotenoid and antioxidant supplementation on retinal function in nonadvanced age-related macular degeneration (AMD). DESIGN: Randomized controlled trial. PARTICIPANTS: Twenty-seven patients with nonadvanced AMD and visual acuity > or =0.2 logarithm of the minimum angle of resolution were enrolled and randomly divided into 2 age-similar groups: 15 patients had oral supplementation of vitamin C (180 mg), vitamin E (30 mg), zinc (22.5 mg), copper (1 mg), lutein (10 mg), zeaxanthin (1 mg), and astaxanthin (4 mg) (AZYR SIFI, Catania, Italy) daily for 12 months (treated AMD [T-AMD] group; mean age, 69.4+/-4.31 years; 15 eyes); 12 patients had no dietary supplementation during the same period (nontreated AMD [NT-AMD] group; mean age, 69.7+/-6.23 years; 12 eyes). At baseline, they were compared with 15 age-similar healthy controls. METHODS: Multifocal electroretinograms in response to 61 M-stimuli presented to the central 20 degrees of the visual field were assessed in pretreatment (baseline) conditions and, in nonadvanced AMD patients, after 6 and 12 months. MAIN OUTCOME MEASURES: Multifocal electroretinogram response amplitude densities (RAD, nanovolt/deg(2)) of the N1-P1 component of first-order binary kernels measured from 5 retinal eccentricity areas between the fovea and midperiphery: 0 degrees to 2.5 degrees (R1), 2.5 degrees to 5 degrees (R2), 5 degrees to 10 degrees (R3), 10 degrees to 15 degrees (R4), and 15 degrees to 20 degrees (R5). RESULTS: At baseline, we observed highly significant reductions of N1-P1 RADs of R1 and R2 in T-AMD and NT-AMD patients when compared with healthy controls (1-way analysis of variance P<0.01). N1-P1 RADs of R3-R5 observed in T-AMD and NT-AMD were not significantly different (P>0.05) from controls. No significant differences (P>0.05) were observed in N1-P1 RADs of R1-R5 between T-AMD and NT-AMD at baseline. After 6 and 12 months of treatment, T-AMD eyes showed highly significant increases in N1-P1 RADs of R1 and R2 (P<0.01), whereas no significant (P>0.05) change was observed in N1-P1 RADs of R3-R5. No significant (P>0.05) changes were found in N1-P1 RADs of R1-R5 in NT-AMD eyes. CONCLUSIONS: In nonadvanced AMD eyes, a selective dysfunction in the central retina (0 degrees -5 degrees ) can be improved by the supplementation with carotenoids and antioxidants. No functional changes are present in the more peripheral (5 degrees -20 degrees ) retinal areas.


Subject(s)
Antioxidants/administration & dosage , Carotenoids/administration & dosage , Electroretinography/drug effects , Macular Degeneration/drug therapy , Retina/drug effects , Administration, Oral , Aged , Ascorbic Acid/administration & dosage , Copper/administration & dosage , Female , Follow-Up Studies , Humans , Lutein/administration & dosage , Macular Degeneration/physiopathology , Male , Middle Aged , Retina/physiopathology , Visual Acuity , Visual Fields , Vitamin E/administration & dosage , Xanthophylls/administration & dosage , Zeaxanthins , Zinc/administration & dosage
4.
Retina ; 27(7): 879-90, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17891012

ABSTRACT

PURPOSE: To evaluate psychophysical and electrophysiologic responses in eyes with early age-related macular degeneration (AMD) without a decrease in visual acuity and with or without late AMD in the fellow eye. METHODS: Fifteen patients (mean age: 67.9 +/- 7.20 years) with early AMD in both eyes (AMD1 group, 15 eyes) and 15 patients (mean age: 71.40 +/- 7.06 years) with early AMD in one eye and late AMD in the fellow eye (AMD2 group, 15 eyes) were enrolled. They were compared to 15 age-similar normal control subjects. LogMAR visual acuity (VA), macular sensitivity by MP-1 microperimetry, and multifocal electroretinograms (mfERG) were assessed in control, AMD1, and AMD2 eyes. mfERG response amplitude density (RAD, nV/deg2) of the N1-P1 component of first order binary kernels was measured. RESULTS: When compared to controls, AMD1 and AMD2 eyes showed a significant (analysis of variance, P < 0.01) decrease in MP-1 microperimetry assessed in the 0-2.5 and 2.5-5 degrees of the macula, significantly correlated (Pearson test, P < 0.01) to the corresponding significant decrease (P < 0.01) in mfERG N1-P1 RADs assessed in the 0-2.5 and 2.5-5 degrees. In AMD1 and AMD2 eyes, VA and mfERG N1-P1 RADs assessed in the 5-20 degrees were similar (P > 0.01) to controls. VA, MP-1, and mfERG values were not significantly different in AMD1 and AMD2 eyes. CONCLUSION: In eyes with early AMD there is a dysfunction of preganglionic elements in the central 0-5 retinal degrees detectable by mfERG or MP-1 microperimetry. This impairment is not further influenced by the presence of late AMD in the fellow eye.


Subject(s)
Macula Lutea/physiopathology , Macular Degeneration/physiopathology , Vision Disorders/physiopathology , Visual Field Tests/methods , Visual Fields/physiology , Aged , Aged, 80 and over , Electrophysiology , Electroretinography , Female , Humans , Male , Middle Aged , Psychophysiology , Visual Acuity/physiology
5.
Retina ; 27(3): 312-20, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17460586

ABSTRACT

PURPOSE: To evaluate macular function before and after surgical peeling of idiopathic epimacular membrane (EMM). METHODS: Logarithm of the minimal angle of resolution visual acuity and results of focal (central 9 x 9 degrees) electroretinogram (fERG), pattern electroretinogram (pERG), and optical coherence tomography (OCT) assessment of macular volume were evaluated for 22 eyes of 22 patients (mean age +/- SD, 63.20 +/- 10.0 years) with EMM preoperatively (baseline) and 6 months after surgical peeling. Preoperative visual acuity and fERG and pERG amplitudes observed in EMM eyes were compared with those in 15 age-matched control eyes. RESULTS: In the preoperative evaluation, EMM eyes had a significant (P < 0.01; one-way analysis of variance) reduction in visual acuity and fERG and pERG amplitudes and an increase in OCT macular volume when compared with controls. In EMM eyes, the decrease in visual acuity was significantly correlated (P < 0.01, Pearson test) to the reduction in fERG and pERG amplitudes. At the postoperative evaluation, EMM eyes had a correlated significant (P < 0.01) increase in visual acuity, fERG amplitude, and pERG amplitude with respect to the preoperative values. All EMM eyes had a significant (P <0.01) reduction in macular volume, and retinal microanatomy was restored to normal conditions. CONCLUSION: In EMM eyes, the decrease in visual acuity is related to dysfunction of both preganglionic (abnormal fERG) and ganglionic (abnormal pERG) macular elements. Surgical removal of EMM may induce improvement of the function of both outer and innermost macular retinal layers, leading to a related increase in visual acuity.


Subject(s)
Electroretinography/methods , Epiretinal Membrane/physiopathology , Epiretinal Membrane/surgery , Photoreceptor Cells, Vertebrate/physiology , Retinal Ganglion Cells/physiology , Adult , Aged , Epiretinal Membrane/diagnosis , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Care , Preoperative Care , Tomography, Optical Coherence , Visual Acuity , Vitrectomy
6.
Invest Ophthalmol Vis Sci ; 46(4): 1453-62, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15790915

ABSTRACT

PURPOSE: To evaluate the effects of photodynamic therapy (PDT) on macular function in myopic subfoveal choroidal neovascularization (CNV). METHODS: Fourteen eyes of 14 patients (mean age, 48.1 +/- 13.3 years) with myopic CNV (myopia ranging from -6.50 to -20 D) were enrolled. In each eye, at baseline and at 15 and 90 days after PDT with verteporfin, logMAR visual acuity (logarithm of the minimum angle of resolution VA), macular sensitivity by scanning laser ophthalmoscope microperimetry, and focal (central 9 x 9 degrees ) ERGs (FERGs) and pattern ERGs (PERGs) were assessed. RESULTS: At 15 days after PDT, myopic CNV eyes showed, in relation to baseline values, a significant (ANOVA, P < 0.01) reduction in the diameter of the lesion that correlated (Pearson test, P < 0.01) with the significant (ANOVA, P < 0.01) increase in FERG and PERG amplitudes, VA, and scanning laser ophthalmoscopy (SLO) microperimetry results obtained from the central 1 degrees to 2 degrees of the macular area (SLO-CM). At 90 days after PDT, myopic CNV eyes showed, in comparison with baseline values, a nonsignificant (ANOVA, P > 0.01) reduction in the diameter of the lesion, a nonsignificant increase in VA and SLO-CM, and a still significant increase in FERG and PERG amplitudes. CONCLUSIONS: In myopic CNV eyes, PDT induces an increase, though not significant, in VA and macular sensitivity. These changes may be related to a reduction in the diameter of the lesion, with an improvement in the function of both ganglionic and preganglionic elements of the macular region, as suggested by the improvement in FERG and PERG responses.


Subject(s)
Choroidal Neovascularization/physiopathology , Electroretinography , Macula Lutea/physiopathology , Myopia, Degenerative/physiopathology , Photochemotherapy , Visual Acuity/physiology , Adult , Aged , Choroidal Neovascularization/drug therapy , Choroidal Neovascularization/etiology , Female , Fluorescein Angiography , Follow-Up Studies , Humans , Lasers , Male , Middle Aged , Myopia, Degenerative/complications , Myopia, Degenerative/drug therapy , Ophthalmoscopy , Photosensitizing Agents/therapeutic use , Porphyrins/therapeutic use , Verteporfin , Visual Field Tests
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