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1.
Ophthalmic Genet ; 42(4): 402-404, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33781147

RESUMO

Renowned French painter Edgar Degas suffered of progressive light sensitivity and blurred central vision in both eyes, which affected his life and art in many ways. A first cousin from his mother's side, Estelle Musson of New Orleans also lost vision in a similar fashion at a comparable age. We postulated that Edgar and Estelle shared the same retinal pathology that possibly developed in a hereditary fashion, and we were interested whether any of their living family descendants might carry ABCA4 mutations to test the possibility that Edgar Degas may have had Stargardt disease.Edgar was never married and had no children, but Estelle had five children, four of whom from her marriage to Edgar's younger brother, and there are several descendants still living in New Orleans area. Genetic testing on five of Estelle's great grandchildren (Edgar's great grandnieces) were performed searching for ABCA4 mutations.We could not document any disease-causing variations in the ABCA4 gene in any of the descendants and therefore concluded that Edgar Degas most likely did not have Stargardt disease. Estelle and Edgar may have shared a different hereditary disease or have had two different retinal dystrophies or had another eye disease, including the unlikely possibility of inflammatory disease.


Assuntos
Pessoas Famosas , Medicina nas Artes , Pinturas/história , Doença de Stargardt/história , Transportadores de Cassetes de Ligação de ATP/genética , França , História do Século XIX , História do Século XX , Humanos , Linhagem , Doença de Stargardt/genética
2.
Eye (Lond) ; 30(2): 287-303, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26563659

RESUMO

The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology.


Assuntos
Oftalmopatias/fisiopatologia , Pinturas , Visão Ocular/fisiologia , Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Humanos , Retina/fisiologia
3.
Doc Ophthalmol ; 118(1): 69-77, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19030905

RESUMO

This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV), presents an updated and revised ISCEV Standard for clinical electroretinography (ERG). The parameters for flash stimulation and background adaptation have been tightened, and responses renamed to indicate the flash strength (in cd x s x m(-2)). The ISCEV Standard specifies five responses: (1) Dark-adapted 0.01 ERG (rod response); (2) Dark-adapted 3.0 ERG (combined rod-cone response); (3) Dark-adapted 3.0 oscillatory potentials; (4) Light-adapted 3.0 ERG (cone response); (5) Light-adapted 3.0 flicker (30 Hz flicker). An additional Dark-adapted 10.0 ERG or Dark-adapted 30.0 ERG response is recommended.


Assuntos
Eletrorretinografia/instrumentação , Eletrorretinografia/normas , Adaptação Ocular , Adulto , Idoso , Idoso de 80 Anos ou mais , Calibragem , Criança , Pré-Escolar , Protocolos Clínicos/normas , Eletrodos , Humanos , Lactente , Estimulação Luminosa/métodos , Projetos de Pesquisa/normas , Estatística como Assunto/métodos , Terminologia como Assunto
4.
Invest Ophthalmol Vis Sci ; 42(11): 2673-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11581215

RESUMO

PURPOSE: To develop a better and more economical instrument for precise, tractionless, "cold" cutting during intraocular surgery. The use of highly localized electric fields rather than laser light as the means of tissue dissection was investigated. METHODS: A high electric field at the tip of a fine wire can, like lasers, initiate plasma formation. Micrometer-length plasma streamers are generated when an insulated 25 micron (microm) wire, exposed to physiological medium at one end, is subjected to nanosecond electrical pulses between 1 and 8 kV in magnitude. The explosive evaporation of water in the vicinity of these streamers cuts soft tissue without heat deposition into surrounding material (cold cutting). Streamers of plasma and the dynamics of water evaporation were imaged using an inverted microscope and fast flash photography. Cutting effectiveness was evaluated on both polyacrylamide gels, on different tissues from excised bovine eyes, and in vivo on rabbit retina. Standard histology techniques were used to examine the tissue. RESULTS: Electric pulses with energies between 150 and 670 microJ produced plasma streamers in saline between 10 and 200 microm in length. Application of electric discharges to dense (10%) polyacrylamide gels resulted in fracturing of the gel without ejection of bulk material. In both dense and softer (6%) gels, layer by layer shaving was possible with pulse energy rather than number of pulses as the determinant of ultimate cutting depth. The instrument made precise partial or full-thickness cuts of retina, iris, lens, and lens capsule without any evidence of thermal damage. Because different tissues require distinct energies for dissection, tissue-selective cutting on complex structures can be performed if the appropriate pulse energies are used; for example, retina can be dissected without damage to the major retinal vessels. CONCLUSIONS: This instrument, called the Pulsed Electron Avalanche Knife (PEAK), can quickly and precisely cut intraocular tissues without traction. The small delivery probe and modest cost make it promising for many ophthalmic applications, including retinal, cataract, and glaucoma surgery. In addition, the instrument may be useful in nonophthalmic procedures such as intravascular surgery and neurosurgery.


Assuntos
Eletrocirurgia/instrumentação , Microcirurgia/instrumentação , Procedimentos Cirúrgicos Oftalmológicos/instrumentação , Retina/cirurgia , Animais , Bovinos , Eletrocirurgia/métodos , Microeletrodos , Microcirurgia/métodos , Coelhos
5.
Am J Ophthalmol ; 132(3): 388-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11530053

RESUMO

PURPOSE: To evaluate the acute effects of sildenafil (Viagra; Pfizer, Inc, New York, New York) on the electroretinogram and multifocal electroretinogram. METHODS: Eighteen healthy individuals (ages 21-49 years) were studied; 14 were given 200 mg sildenafil orally and four were given only water. All subjects were tested before sildenafil and 1 hour after sildenafil (or water) with a desaturated Panel D-15 color test, a full-field standard electroretinogram, and a multifocal electroretinogram using the VERIS system; five subjects were also tested 5 hours after sildenafil. RESULTS: Responses from the subjects who received sildenafil were compared with those from the control subjects. At 1 hour after sildenafil, photopic single-flash waveforms were attenuated by 9% and scotopic maximal response amplitudes were increased slightly. Photopic and 30-Hz flicker electroretinogram responses were delayed; multifocal electroretinogram waveforms were delayed (5%-9%) and attenuated (14%-22%) across the posterior pole. These changes did not resolve by 5 hours. Nine of the subjects who had received sildenafil (64%) reported visual or systemic symptoms, including one who reported bluish vision. Ten of those subjects (71%) showed a slight increase in color test errors 1 hour after sildenafil. CONCLUSIONS: For at least 5 hours after taking 200 mg of sildenafil, cone function was slightly depressed in the macula and periphery, as measured by full-field electroretinogram and multifocal electroretinogram recordings. However, the affected electroretinogram and multifocal electroretinogram parameters still remained within normal limits.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Eletrorretinografia/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Piperazinas/farmacologia , Adulto , Percepção de Cores/efeitos dos fármacos , Percepção de Cores/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Purinas , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Células Fotorreceptoras Retinianas Cones/fisiologia , Citrato de Sildenafila , Sulfonas , Fatores de Tempo
7.
Surv Ophthalmol ; 45(5): 407-15, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11274694

RESUMO

No "major" painter is known to be color deficient. Are there truly no color deficient artists, or have they not been recognized? The historical literature cites criteria for recognizing color deficiency in artists, but they are hard to apply without knowing the intentions of an artist. The work and commentary of a color-deficient artist who works currently in Paris are presented as an example. He uses a limited palette of colors, based on advice from colleagues as much as his own perceptions, and he uses colors in ways that do not always fit with expectations for color deficiency. Biographies of earlier painters suggest that there were a few whose color sense was poor, but these painters used assistants to help. The color sense of others, such as the English landscape painter John Constable (1776-1837), has been questioned because of a preponderance of suspicious color, such as murky green. However, there are good reasons to doubt that Constable was color deficient. It is instructive to know how proven color deficiency has influenced an artist's style. When medical information is unavailable, the best advice for the diagnostically-inclined observer is just to enjoy the art.


Assuntos
Percepção de Cores , Defeitos da Visão Cromática/história , Oftalmologia/história , Pinturas , Percepção de Cores/fisiologia , Defeitos da Visão Cromática/diagnóstico , Defeitos da Visão Cromática/fisiopatologia , Diagnóstico Diferencial , Inglaterra , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Pinturas/história , Paris
8.
Doc Ophthalmol ; 101(1): 11-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11128964

RESUMO

The pattern electroretinogram (PERG) is a retinal response evoked by viewing an alternating checkerboard or grating. It receives clinical and research attention because it can provide information about inner retinal cells and the macula. However, clinicians may have trouble choosing between different techniques for recording the PERG that have been described in the literature. The International Society for Clinical Electrophysiology of Vision has prepared a standard for a basic PERG recording procedure to aid new users in obtaining reliable responses and to encourage more uniformity among existing users.


Assuntos
Eletrofisiologia/normas , Eletrorretinografia/normas , Guias de Prática Clínica como Assunto/normas , Retina/fisiologia , Protocolos Clínicos , Eletrodos , Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Eletrorretinografia/instrumentação , Saúde Global , Humanos , Sociedades Médicas , Terminologia como Assunto
9.
J Neuroophthalmol ; 20(4): 227-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11130743

RESUMO

OBJECTIVE: To study the effects of sildenafil on blue-on-yellow and white-on-white Humphrey visual field (HVF). MATERIALS AND METHODS: Healthy subjects, ages 20 to 38 years, were prospectively randomized to active drug (n = 5) or placebo (n = 3) groups. Blue-on-yellow and white-on-white HVF testing was performed before and 1 hour after masked dosing of sildenafil 200 mg or placebo. Changes in mean deviation (MD) were compared between groups. RESULTS: Three of three placebo and four of five sildenafil subjects had no change on HVF. One of five sildenafil subjects had a decrease in MD of 17.9 dB and 4.7 dB on blue-on-yellow and white-on-white HVF testing, respectively. This subject reported more systemic side effects than other subjects. CONCLUSIONS: Sildenafil has no effect on HVF testing in most persons; however, sildenafil caused an acute abnormality of HVF testing in one subject, who experienced pronounced non-visual systemic symptoms; this effect was greater on blue-on-yellow than white-on-white HVF.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Piperazinas/farmacologia , Campos Visuais/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Purinas , Retina/efeitos dos fármacos , Citrato de Sildenafila , Sulfonas , Testes de Campo Visual
10.
Arch Ophthalmol ; 118(9): 1211-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10980766

RESUMO

OBJECTIVE: To examine results of the multifocal electroretinogram (MERG) after spontaneous resolution of central serous chorioretinopathy (CSC) detachments. METHODS: Multifocal electroretinograms were recorded from both eyes of 5 recovered patients with CSC and 10 age-matched healthy subjects. All patients with CSC had bilaterally subnormal MERG amplitudes during a first attack of CSC occuring 7 to 23 months earlier. RESULTS: After recovery from CSC, MERG A-wave and B-wave amplitudes increased markedly where the detachment resolved, and moderately elsewhere in the posterior pole of both eyes. However, the signals from both eyes remained either subnormal or low-normal relative to controls. Multifocal electroretinogram B-wave latencies improved from prolonged to mid-normal values in both eyes. CONCLUSIONS: Both eyes of patients with active unilateral CSC exhibit diminished MERG amplitudes. Although MERG response amplitudes increased modestly after recovery from CSC, they remained statistically subnormal throughout the posterior pole of both eyes. These findings support the theory that subretinal fluid retention in CSC is secondary to diffuse pathologic changes in the choroid and/or retinal pigment epithelium. They also suggest that the underlying or predisposing abnormalities of CSC resolved only partially in our patients. Components of the MERG may have value as a prognostic tool for judging the risk of developing symptomatic CSC. Arch Ophthalmol. 2000;118:1211-1215


Assuntos
Doenças da Coroide/fisiopatologia , Eletrorretinografia/métodos , Retina/fisiopatologia , Doenças Retinianas/fisiopatologia , Adulto , Doenças da Coroide/diagnóstico , Exsudatos e Transudatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Remissão Espontânea , Doenças Retinianas/diagnóstico , Acuidade Visual
11.
Surv Ophthalmol ; 44(4): 343-53, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10667441

RESUMO

Metamorphopsia is a symptom of retinal distortion from intrinsic retinal disease. It has undoubtedly been experienced for millennia, but its clinical significance has been appreciated only in modern times. The Norwegian painter Edvard Munch recognized scotomas and metamorphopsia after suffering an intraocular hemorrhage in his 60th year. Drawings made during this illness show his changing perceptions, and also his attempts to document them with a grid of lines. The Scottish philosopher Thomas Reid may have been the first to write about metamorphopsia. He described distortion of his vision in 1764, after an episode of sungazing, and recognized that the problem was probably of retinal origin. Lines or grids to document metamorphopsia have appeared in ophthalmology textbooks for more than 100 years, but testing for macular degeneration did not become routine until the dissemination of Amsler's grids in the middle of the 20th century. This is in large measure a result of developments in ophthalmology that made therapy for macular disease possible.


Assuntos
Medicina nas Artes , Doenças Retinianas/história , Transtornos da Visão/história , Testes Visuais/história , Campos Visuais , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Noruega , Pinturas/história , Escócia , Suíça
12.
Graefes Arch Clin Exp Ophthalmol ; 238(1): 76-80, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10664057

RESUMO

BACKGROUND: The clinical use of currently available carbonic anhydrase (CA) inhibitors is limited by systemic side-effects, thought to result from the inhibition of intracellular CA isoenzymes. This study investigates how benzolamide, a carbonic anhydrase inhibitor which does not readily penetrate cell membranes, modulates retinal pigment epithelium functions relative to acetazolamide, which diffuses into the cytosol. METHODS: Small retinal detachments were made in Dutch rabbits by injecting saline into the subretinal space. Detachment height was measured using a dual He-Ne beam YAG laser focusing system, and the fluid absorption rate was calculated before and after intravenous injections of saline, acetazolamide or benzolamide. Retinal adhesiveness was determined by peeling the retina from the RPE and measuring the amount of adherent pigment. RESULTS: The baseline fluid absorption rate of 0.04 microl/mm(2)/h was unchanged after injection of 0.9% NaCl or low-dose benzolamide (5 mg/kg). The absorption increased to about 0.14 microl/mm(2)/h after higher benzolamide doses (20-40 mg/kg) and to 0.13 microl/mm(2)/h after acetazolamide (20 mg/kg). Both acetazolamide and benzolamide significantly slowed the post-enucleation failure of retinal adhesiveness. CONCLUSION: Since benzolamide had effects similar to acetazolamide, inhibition of membrane-bound CA appears to be sufficient to enhance subretinal fluid absorption and retinal adhesiveness. Membrane-specific CA inhibitors may therefore be of clinical value if they minimize side-effects from intracellular CA inhibition.


Assuntos
Acetazolamida/farmacologia , Benzolamida/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Exsudatos e Transudatos/metabolismo , Epitélio Pigmentado Ocular/metabolismo , Descolamento Retiniano/tratamento farmacológico , Absorção/efeitos dos fármacos , Adesividade/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Modelos Animais de Doenças , Exsudatos e Transudatos/efeitos dos fármacos , Líquido Intracelular/enzimologia , Epitélio Pigmentado Ocular/efeitos dos fármacos , Epitélio Pigmentado Ocular/patologia , Coelhos , Descolamento Retiniano/patologia , Descolamento Retiniano/cirurgia
13.
Yan Ke Xue Bao ; 16(4): 254-8, 2000 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12579783

RESUMO

PURPOSE: To detect the sensitivity and the repeatability of multifocal electroretinogram (mfERG). METHOD: The effects of experimental absolute and relative scotomas on mfERG with 103 hexagons were observed on 8 normal eyes. The scotomas were produced by simultaneous and multi located masks on the hexagons of the screen in 6 different locations with black paper, and the neutral filters of 0.3 and 0.6 log unit. The repeatability was evaluated by analysis the data from 5 unmasked hexagons in 4 successive tests. RESULTS: When the hexagons were 1/2 or wholly masked with the black paper and the two kinds of the filters, the amplitudes of N1 and P1 waves in these areas were significantly decreased as with the reduced transferability of light. When the hexagon was 1/3 masked, there were no significant differences between the different kinds of mask and the unmasked control. There were no significant changes in the datas from the selected unmasked hexagons in the 4 successive recordings. CONCLUSION: mfERG is an unique sensitive visual electrophysiological test with high sensitivity and good repeatability. When 103 hexagons stimulating pattern is used, it could detect the scotoma larger than 1/3 of each hexagon.


Assuntos
Eletrorretinografia , Retina/fisiologia , Escotoma/diagnóstico , Adulto , Eletrorretinografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Escotoma/fisiopatologia , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Acuidade Visual
15.
Surv Ophthalmol ; 44(2): 153-62, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10541153

RESUMO

Sildenafil citrate (Viagra) is a new oral medication that inhibits phosphodiesterase-5 (PDE5) in the corpus cavernosum to facilitate penile erection for the treatment of male impotence. The drug also has a mild inhibitory effect on PDE6, which controls the level of cyclic guanosine monophosphate in the retina, and it may cause a perception of bluish haze or increased light sensitivity in some patients. Long-term retinal damage has not been reported, but long-term electroretinographic studies have not been performed. Sildenafil causes a mild lowering of blood pressure and is absolutely contraindicated in patients taking any form of nitrate medication. A number of cardiovascular deaths and retinal vascular events in patients taking sildenafil have been reported, but so far the rate of these complications does not exceed expectation for an elderly population. Ophthalmologists should alert patients to the ocular side effects and potential risks of this new drug until further clinical experience has been obtained.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Oftalmologia/métodos , Inibidores de Fosfodiesterase/efeitos adversos , Piperazinas/efeitos adversos , Doenças Retinianas/induzido quimicamente , Disfunção Erétil/tratamento farmacológico , Humanos , Purinas , Retina/efeitos dos fármacos , Retina/enzimologia , Doenças Retinianas/prevenção & controle , Segurança , Citrato de Sildenafila , Sulfonas , Acuidade Visual/efeitos dos fármacos
16.
Am J Ophthalmol ; 128(3): 378-80, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10511044

RESUMO

PURPOSE: To describe a morphologic variant of the multiple evanescent white-dot syndrome that can mimic other conditions. METHODS: We examined three patients with severe cases of unilateral multiple evanescent white-dot syndrome characterized by an atypical progressive circumpapillary discoloration of the fundus. RESULTS: The confluent circumpapillary lesion progressed toward or beyond the equator of the fundus, raising initial concern of a viral retinitis. However, pinpoint dots at the leading edge evolved into the typical wreath-like spots of multiple evanescent white-dot syndrome, which then coalesced into the advancing edge of a geographic retinitis or retinal pigment epitheliitis, before spontaneous resolution. CONCLUSION: Progressive geographic circumpapillary discoloration, appearing as a giant white spot, occurs rarely in severe cases of multiple evanescent white-dot syndrome. The distinctive appearance may suggest a disorder other than multiple evanescent white-dot syndrome, which can make initial diagnosis more difficult and lead to unnecessary or inappropriate testing and treatment.


Assuntos
Disco Óptico/patologia , Doenças Retinianas/diagnóstico , Adulto , Progressão da Doença , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Masculino , Síndrome , Acuidade Visual
17.
Arch Ophthalmol ; 117(9): 1227-35, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10496396

RESUMO

George K. Kambara has been a leader in ophthalmic education and practice on the West Coast. His choice of ophthalmology arose in part because of his experience running an eye, ear, nose, and throat clinic while interned as a Japanese American during World War II. His training took him from San Francisco, to the Tule Lake Relocation Center, to the Memphis Eye, Ear, Nose and Throat Hospital, to the University of Wisconsin, and eventually back to Los Angeles. He saw both sides of discrimination, as a Japanese American in California and as a "white" in the South. He was turned down for positions that he should have had based on his education, but he was also supported by many individuals who put aside public fears to help him. His story shows a triumph of the spirit, but is also a reminder of dark times that should not be forgotten.


Assuntos
Educação Médica/história , Oftalmologia/história , Asiático/história , California , História do Século XX , Oftalmologia/educação , Tennessee , Wisconsin
19.
Invest Ophthalmol Vis Sci ; 40(8): 1866-73, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10393063

RESUMO

PURPOSE: To investigate the topography of cone electroretinographic (ERG) responses in the enhanced S cone syndrome (ESCS). METHODS: A 19-year-old female with ESCS who was one of the original cases defining the syndrome was studied. Full-field, focal (Maculoscope) and multifocal (VERIS) ERGs were performed using white light. Multifocal ERG responses were also generated with red and blue stimuli and with a slow m-sequence to elicit off-responses. Results were analyzed by averaging data in rings at increasing eccentricity from the fovea and compared to data recorded identically from a normal subject. RESULTS: The full-field ERG from this patient showed typ ical large slow photopic waveforms and was unchanged from recordings made 9 years earlier. The focal ERG showed signals of borderline low amplitude from the fovea with the multifocal ERG, the ESCS responses from the central macula had a relatively normal waveform, and those 9 degrees to 20 degrees from fixation showed the prolonged wave-form that characterizes the full-field ERG. Responses were larger to blue light than red light in ESCS in both center and periphery. The central ESCS responses were relatively normal in timing to both red and blue light, whereas the peripheral ESCS responses were markedly delayed to both. Off-responses were seen in ESCS only near the foveal center. CONCLUSIONS: The marked differences between central and peripheral ERG responses in ESCS suggest that there are different distributions of S, L, and M cones in these regions and that S cones may feed into different neural pathways in the center and periphery. It was postulated that in ESCS, S cones may partially replace L and M cones centrally and feed into the usual S cone pathways. In the periphery, however, there is little L and M cone b-wave activity in ESCS, and S cones may usurp both the space and neural pathways of the rods.


Assuntos
Eletrorretinografia , Células Fotorreceptoras Retinianas Cones/fisiopatologia , Degeneração Retiniana/fisiopatologia , Adulto , Adaptação à Escuridão , Feminino , Seguimentos , Humanos , Células Fotorreceptoras Retinianas Cones/patologia , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/fisiopatologia , Síndrome , Vias Visuais/fisiopatologia
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