Effects of acupuncture on morphological changes of photoreceptor cells in rats with retinitis pigmentosa / 中国针灸

<p><b>OBJECTIVE</b>To observe the morphological changes of photoreceptor cells in rats with retinitis pigmentosa (RP) induced by N-methyl-N-Nitrosourea (MNU) and the effects of acupuncture against it.</p><p><b>METHODS</b>A total of 16 SD rats were treated with one-time intraperitoneal injection of MNU (50 mg/kg) to induce RP, and randomly divided into an acupuncture group and a model group, 8 rats in each one. In addition, 4 rats were selected as a control group. After model establishment, rats in the acupuncture group were treated with acupuncture at "Xinming-1" (Extra) and "Jingming" (BL 1) for 30 min, once a day for 7 days; rats in the model group and control group received no treatment, and the feeding conditions and fixation were identical as the acupuncture group. 2 h after the end of intervention, rats were sacrificed by cervical dislocation to observe the morphological changes of rhodopsin, rod terminals and rod bipolar cells.</p><p><b>RESULTS</b>Due to the loss of retina photoreceptor cells induced by MNU in rats, in the model group the rhodopsin was stained in residual cell bodies, and there were sporadic rod terminals and little rod bipolar cells; outer segments, inter segments, cell bodies and cell terminals were all affected at different levels. The distribution of rhodopsin was also changed in the acupuncture group, showing more bodies of photoreceptor cells, and the residual rod terminals and rod bipolar cells were more than those in the model group; the injury of retina was less than that in the model group.</p><p><b>CONCLUSION</b>MNU could lead to a comprehensive injury to the morphology of photoreceptor cells, however, acupuncture is capable of inhibiting morphological changes of photoreceptor cells induced by MNU.</p>

Electroretinogram and histopathologic changes of the retina after methanol intoxication / 法医学杂志

In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication, 35 rats were divided randomly into five groups administrated with saline, 3-day high dose, 7-day high dose, 3-day low dose and 7-day low dose methanol separately. The retinal function of each group was assessed by flash electroretinogram (F-ERG) 3 and 7 days after methanol poisoning. The microstructure and ultrastructure of the retina were observed at the same time. The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning, which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG. These injuries were aggravated 7 days after poisoning. Meanwhile, the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning, but there were no further worsening tendency 7 days after poisoning. The retinal histological analysis showed cellular edema, heteromorphy and disarrangement, tissular loosen of the inner nuclear layer and photoreceptors layer. The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer. The low-dose methanol intoxication only caused transient damage of the retina. Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells. The mitochondrial damage developed from outer layer to inner layer of the retina.

EGB761 on retinal light injury in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Retinal light injury can lead to degeneration of the photoreceptor cell layer. It has been hypothesized that the mechanism for this process is the photochemical damage. Ginkgo balboa extract (Ginkgo biloba extract EGB761) EGB761 is a free radical scavenger. The purpose of this study was to investigate the possible effect of orally administered EGB761 on retinal light damage of mouse photoreceptor cells.</p><p><b>METHODS</b>Kunming mice were randomly chosen for the following groups containing 20 animals in each: control group, light damage group, saline control group, and drug treatment group. The drug treatment group and saline control group were given daily gavage of EGB761 (150 mg×kg(-1)×d(-1)) one week before light exposure. At 7, 14, and 30 days after light exposure, animals were sacrificed and eyes were examined by light microscopy, electron microscopy, and retinal histopathology using in situ detection of apoptotic cells.</p><p><b>RESULTS</b>In the light damage group after 7 days there was visible edema, and the outer nuclear layer appeared withered with deeply stained dead cells, leaving only a thin nuclear layer of 7 - 8 cells. After 14 days, the photoreceptor cell layer disappeared, leaving only the outer nuclear layer of 1 - 3 cells with an average thickness of (37.988 ± 1.207) µm. The average thickness of the retina was (126.32 ± 2.31) µm. In the drug treatment group, the photoreceptor cell layer and outer nuclear layer damage were significantly lower than the saline group (t = 21.993, P < 0.001), demonstrating that EGB761, especially at 14 days after light exposure, can reduce retinal light damage in mice.</p><p><b>CONCLUSION</b>Oral administration of EGB761 can partially inhibit apoptosis of photoreceptor cells, resulting in increased photoreceptor cell survival.</p>

Preenchimento perceptivo da mancha cega não distorce a percepção do tamanho linear / Filling-in of the blind spot does not distort linear size perception

Ao se olhar o mundo monocularmente, não se percebe que há uma mancha cega no campo visual correspondente ao disco óptico, região da retina em que não há fotorreceptores. Ao contrário, bordas e padrões de superfícies são percebidos como se fossem detectados por fotorreceptores, fenômeno denominado preenchimento perceptivo. Para investigar se o preenchimento perceptivo distorce o espaço percebido, trinta adultos tiveram suas manchas cegas do olho direito mapeadas e fizeram as comparações de tamanho de pares de barras horizontais em condição monocular direita. Os resultados apontam uma assimetria lateral no campo visual central do olho direito nas comparações de tamanho e que o preenchimento perceptivo na mancha cega não distorce o espaço visual percebido.

When looking at the world monocularly, we do not perceive that there is a blind spot in the visual field corresponding to the optic disc, the region of the retina where there are no photoreceptors. In contrast, we perceive edges and patterns of surfaces as if were detected by photoreceptors. This phenomenon is called filling-in. To investigate whether the filling-in distorts space perception, thirty adults had their right eye blind spots mapped and they compared the length of two horizontal bars under right monocular viewing condition. The results point out a lateral asymmetry in the central visual field of the right eye in length comparisons and that the filling-in effect at the blind spot does not distort visual space perception.

Immunohistochemical localization of cyclic AMP-responsive element binding protein (CREB)-binding protein in the pig retina during postnatal development / 대한해부학회지

This study evaluated the cellular localization of cyclic AMP-responsive element binding protein-binding protein (CBP) expression in pig retinas during postnatal development. Immunohistochemistry and Western blot analysis were performed on retinal tissue from 2-day-old, 5-week-old, and 6-month-old pigs. Western blot analysis detected the expression of CBP in the retinas of 2-day-old piglets and showed that it was significantly decreased in the retinas of 5-week-old and 6-month-old pigs. Immunohistochemically, CBP was intensely immunostained in protein kinase C alpha (PKCalpha)-positive-bipolar cells, glutamine synthetase-positive Muller cells, and in ganglion cells in 2-day-old piglets. CBP was detected weakly in the inner plexiform, outer nuclear, and rod and cone layers. CBP immunoreactivity in the ganglion cell layer was decreased in the retinas of 5-week-old and 6-month-old pigs, while clear CBP expression detected in the neurite of PKCalpha-positive bipolar cells in the inner nuclear layer. In addition, CBP immunoreactivity in Muller cells and glial fibrillary acidic protein-positive glial processes was particularly noteworthy in pig retinas, but not in rat retinas. The results indicate that CBP is expressed differentially in the retinal neurons and glial cells according to growth and animal species, and may play an important role in homeostasis in Muller cells, neurite extention in bipolar cells, and signal transduction in photoreceptor cells in the porcine retina.

Photoreceptor Disruption Related to Persistent Submacular Fluid after Successful Scleral Buckle Surgery

PURPOSE: To investigate serial changes in photoreceptor status and associated visual outcome in patients with persistent submacular fluid after successful scleral buckle surgery for macula-off rhegmatogenous retinal detachment. METHODS: This was a prospective observational case series including 76 consecutive patients who underwent successful scleral buckle surgery for macula-off rhegmatogenous retinal detachment with symptom duration < or =90 days at a single tertiary hospital. Optical coherence tomography (OCT) and visual acuity examination were performed at one month and three months postoperatively and at three-month intervals until the submacular fluid disappeared. Main outcome measures were postoperative photoreceptor status on OCT and visual acuity. RESULTS: Forty-two patients (55.3%) showed persistent submacular fluid at postoperative one month. Of 42 patients with persistent submacular fluid, three (7.1%) showed photoreceptor disruption on OCT. None of the 34 patients without persistent submacular fluid showed photoreceptor disruption. Two patients (4.8%) had progressive photoreceptor disruption, and one patient (2.4%) had early photoreceptor disruption. All three patients showed photoreceptor reappearance and limited visual restoration after absorption of submacular fluid. Final visual acuities were significantly worse in these three patients (20 / 1000, 20 / 133, and 20 / 133) compared to those of the other patients (mean, 20 / 30) with persistent submacular fluid and intact photoreceptors. CONCLUSIONS: Even after successful scleral buckle surgery for rhegmatogenous retinal detachment, photoreceptor disruption can occur related to persistent submacular fluid and may be a cause of poor visual outcome.

Ultrastructure alterations of retinal photoreceptors of the black rat, Rattus rattus exposed to certain heavy metals

This study was designed to investigate the impact of lead and cadmium on the retinal photoreceptors of rats. Adult black rats, Rattus rattus, were selected and divided into control and exposed groups. The exposed group was housed in industrial car batteries room containing fumes of lead and cadmium. The retina prepared for scanning and transmission electron microscopy. The scanning electron microscopy revealed different lead-cadmium changes represented by gradual increasing in spaces between segments of the photoreceptors, associated with swelling of their inner segments and accompanied with rupture, degeneration and decreased numbers of some rods and cones in the outer segments. Disorganization, shortening, a decrease in number of the photoreceptors and a great deformity were the characteristic changes after prolonged exposure to the heavy metals. The aforementioned damages of the photoreceptors were confirmed at the ultrastructural level using transmission electron microscope in the form of progressive disorganization, shortening, swelling, widening of the intradiscal spaces, vacuolization and degeneration of the lamellae of the outer segments [OS], followed by the damage of mitochondria of the inner segments[IS]. Excessive penetration of the processes of the pigmented epithelium [PE] filled with pigments of different shapes and sizes between the damaged segments were noted. These pathological changes were considered the first symptoms in the retinal toxicity. The present results are alarming and call for further investigations to elucidate the impact of exposure to these heavy metals for longer periods on the rat vision and eye structure

Restraining effects of acupuncture on photoreceptor cell apoptosis in rats with retinitis pigmentosa induced by N-methyl-N-nitrosourea / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of acupuncture on photoreceptor cell apoptosis in rats with retinitis pigmentosa induced by N-methyl-N-nitrosourea (MNU).</p><p><b>METHODS</b>Fifty-day-old female SD rats were established into model of retinitis pigmentosa by once intraperitoneal injection of 50 mg/kg MNU, and randomly grouped to the acupuncture group and the model group for observing the cell apoptosis in rats and compared with that in normal rats at the corresponding time points.</p><p><b>RESULTS</b>Acupuncture showed no effect on cell apoptosis at its peak of occurring, apoptotic phenomena still could be seen on days 5 and 7, but it was significantly less in the acupuncture group than in the model group (P < 0.01). Moreover, acupuncture showed a restraining effect on the up-regulation of caspase-3 activity.</p><p><b>CONCLUSION</b>Acupuncture can restrain the MNU induced apoptosis of photoreceptor cells, the effect is correlated, to a certain degree, with the status of the apoptosis occurrence.</p>

Structural Alterations of Retinal Detachment After Intravitreal Triamcinolone Injection in Rabbit Eyes

PURPOSE: To investigate the effect of localized retinal detachment on both the detached and attached regions, and to determine the effect of triamcinolone on Muller cell gliosis. METHODS: Pars plana vitrectomy was performed in both eyes of 12 pigmented rabbits. A dome shaped retinal detachment was made by injecting sodium hyaluronate into the subretinal space. Triamcinolone (5 mg) was applied intravitreally to one eye (12 eyes). The detached retinal area and the neighboring attached region were studied by light and electron microscopy 3, 7, and 28 days after surgery. Tissues were prepared in 5 um sections for hematoxylin-eosin staining and immunohistochemistry with antibody to glial fibrillary acidic protein (GFAP). RESULTS: In addition to the well-known degeneration of photoreceptor cells in the detached retina, an incomplete but severe loss of ganglion cell axons occurs in both the detached and the attached regions. The total retinal thickness gradually decreased in the detached areas, while the thickness of the inner retinal layers remained virtually unchanged over several weeks. Gliotic alterations were apparent in both the detached and non-detached retinal areas, and intravitreal triamcinolone did not alter these gliotic alterations of Muller cells. CONCLUSIONS: It is noteworthy that progressive retinal destruction also occurs in the attached retina after local detachment. This may account for visual impairment in strikingly large areas of the visual field, even after retinal reattachment.

Estudo do buraco macular fechado cirurgicamente: avaliação da relação entre a integridade da camada de fotorreceptores e a acuidade visual final por meio da tomografia de coerência óptica / Optical coherence tomography evaluation of surgically closed macular holes: photoreceptor layer analysis and its correlation with final visual outcome

O objetivo deste estudo foi correlacionar a integridade da camada dos fotorreceptores da retina com a visão final obtida em pacientes operados de buraco macular idiopático. Foram colhidas imagens tomográficas da região foveal de 39 olhos de 37 pacientes operados com sucesso a mais de um ano. Dados adicionais pré-operatórios como o tamanho do buraco, tempo de duração da doença e acuidade visual inicial também foram obtidos. Os olhos foram divididos em três grupos por ordem crescente de integridade da camada dos fotorreceptores. Os olhos pertencentes ao grupo de maior integridade apresentaram acuidade visual final significativamente superior aos alocados no grupo de menor integridade. As características iniciais dos buracos não se relacionaram com o resultado visual final. Concluiu-se que uma maior integridade da camada de fotorreceptores exerce papel importante na recuperação da visão em pacientes operados de buraco macular...

The objective of this study was to correlate the integrity of the retinal photoreceptor layer with final visual acuity in successfully operated macular hole patients. Using optical coherence tomography, foveal images were obtained from 39 eyes of 37 patients. Additionally, lesion pre-operative data was collected involving initial visual acuity, lesion size and time duration of the symptoms. All eyes were then included in one of three groups according to their photoreceptor integrity. Optical coherence tomography data obtained shown that those eyes included in the group with better integrity presented superior visual acuity when compared to the other groups. The results were statistically significant. Baseline lesion characteristics did not correlate with a better outcome. In conclusion, post-operative integrity of the photoreceptor layer plays an important role in achieving good visual recovery in macular hole surgery...

Perfil clínico e eletrorretinográfico da comoção retiniana / Clinical and electroretinographic profile of commotio retinae

OBJETIVO: Traçar perfil clínico, anatômico e funcional da comoção retiniana. MÉTODOS: Pacientes com trauma ocular contuso e quadro fundoscópico de comoção retiniana unilateral há menos de 72 horas foram submetidos ao exame de acuidade visual, biomicroscopia, oftalmoscopia binocular indireta, retinografia, angiografia fluoresceínica, tomografia de coerência óptica e eletrorretinografia de campo total. A eletrorretinografia foi repetida após 15 e 30 dias. A angiografia após 30 dias. RESULTADOS: Foram incluídos 16 pacientes no estudo. No primeiro exame, havia diferença estatisticamente significante entre o olho atingido e o olho controle na amplitude de todas as respostas, sem alteração da relação b/a, e na latência da resposta de cones isolados e do flicker a 30 Hz. No segundo exame, manteve-se a diferença para os potenciais oscilatórios, que desapareceu no último exame. Na angiofluoresceinografia, todos os olhos acometidos mostravam áreas de hiperfluoresceência por transmissão alternadas com áreas de hipofluorescência por bloqueio. Este defeito mantém-se após 30 dias. A tomografia de coerência óptica mostrou diminuição da refletividade na camada dos fotorreceptores. CONCLUSÕES: As alterações encontradas refletiram acometimento de fotorreceptores e de células ganglionares, mas não da camada de células bipolares, além de mobilização precoce de pigmento do epitélio pigmentado da retina. As alterações eletrorretinográficas desapareceram após 30 dias do trauma.

PURPOSE: To investigate clinical, anatomic and electroretinographic changes in eyes that suffered blunt ocular trauma with commotio retinae. METHODS: Patients who presented commotio retinae after unilateral blunt ocular trauma less then 72 hours before were submitted to visual acuity testing, biomicroscopy, binocular indirect ophthalmoscopy, fluorescein angiography, optical coherence tomography and full-field electroretinography. Full-field ERG was repeated after 15 and 30 days. RESULTS: Sixteen patients were included in the study. On the first examination there was a statistically significant difference between affected and fellow eye in all response amplitudes, without b/a ratio alteration, and a delay in single-flash cone response and 30-Hz flicker implicit time. On the second examination, the difference between the eyes remained for oscillatory potentials, but disappeared on the last examination. In fluorescein angiography, all patients presented mottled hyperfluorescence and hypofluorescent areas, due to alterations in the pigment barrier. On optical coherence tomography, we found optically empty spaces at the site of the lesion. CONCLUSION: Found changes suggested photoreceptor and ganglion cells, but not Müller cell functional alterations, as well as pigment mobilization. These changes disappeared 30 days after the trauma.

Early Reversible Changes on ERG in Pharmaceutically Induced Retinal Degeneration in Rats

PURPOSE: To evaluate the early ERG (electroretinogram) changes in N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in rats. METHODS: Thirty-six 6-week-old male rats were injected intraperitoneally with 60mg/kg MNU and divided into 6 groups. Histology and ERG were recorded for the rats of each group before treatment and at 3, 6, 12, 18, and 24 hours after MNU injection. Promptly after the ERG recording, rats were sacrificed and the eyeballs prepared for histologic sectioning. The Tdt-mediated dUTP-digoxigenin nick end labeling (TUNEL) method was used to detect photoreceptor cell death. RESULTS: The first decreases of ERG responses were noticed maximally at 3 hours after the treatment. Thereafter, the amplitude of the responses was partially recovered at 12 hours post-treatment. The second decrease of ERG amplitudes was observed in the 18-hour recordings, and those changes progressed to 24 hours after the treatment. In the histologic findings, TUNEL (+) cells in the Outer Nuclear Layer (ONL) were not detected at 3 hours after MNU injection, but were initially noticed at 6 hours post-injection. CONCLUSIONS: The first decreases of ERG amplitudes proceeded the appearance of TUNEL (+) cells in ONL, and these electrophysiological changes seemed to not be related to photoreceptor cell death. We propose that electrophysiological changes observed might be related to the MNU-induced activity enhancement of guanylate cyclase in the phototransduction pathway. We also show that photoreceptor cell death in the MNU-induced retinal degeneration model occurs at 6 hours after the treatment, which is earlier than the results of previous reports.

Empleo de las sustancias neurotróficas como terapéutica en la retinosis pigmentaria / Use of neurotrophic substances as therapeutics in retinitis pigmentosa

Se hizo una revisión sobre las sustancias neurotróficas como terapéutica en la retinosis pigmentaria, una de las distrofias retinianas más estudiadas. Es una enfermedad crónica no transmisible, con gran heterogeneidad clínica y genética, la cual se caracteriza por la pérdida progresiva de los fotorreceptores, lo que conduce a la ceguera. Su tratamiento constituye uno de los graves problemas no resueltos aún a escala mundial. Recién se han publicado trabajos científicos sobre nuevas sustancias que pueden tener efecto neuroprotector, angiogénico y mitogénico, sobre el sistema nervioso, específicamente en los elementos celulares de la retina. Estas sustancias neurotróficas sugieren una alternativa terapéutica, a corto plazo, en las enfermedades neurodegenerativas de la retina, con gran éxito y recuperación de la función visual de las células que no han muerto, mediante la modulación del proceso de apoptosis en modelos animales con retinosis pigmentaria. Se espera que en un futuro se utilicen en combinación con otras técnicas de mayor alcance, como por ejemplo la terapia génica

Protective effects of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea and its mechanism / 药学学报

<p><b>AIM</b>To study the protective effect of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley (SD) rats.</p><p><b>METHODS</b>Ligustrazine injections of different doses were injected intraperitoneally into 47-day female SD rats once a day and a single intraperitoneal injection of MNU 60 mg x kg(-1) was given to 50-day rats. At different intervals after MNU treatment,the animals were sacrificed. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling at 24 h following MNU treatment; peripheral retinal damage was evaluated based on retinal thickness at the d 7 after MNU treatment, and the expression of c-jun and c-fos genes was detected by RT-PCR technique.</p><p><b>RESULTS</b>Ligustrazine injection could remarkably increase total thickness of peripheral retina and decrease apoptotic index of photoreceptor cells induced by MNU in a dose-dependent manner. Compared with MNU-treated rats, the gene expression of c-jun and c-fos was time-dependently down-regulated in ligustrazine-treated group.</p><p><b>CONCLUSION</b>Ligustrazine injection partially protects against MNU-induced retinal damage by down-modulating the expression of c-jun and c-fos genes to inhibit apoptosis of photoreceptor cells.</p>

N-methyl-N-nitrosourea-induced apoptosis of photoreceptor cells in Sprague-Dawley rats via nuclear factor-kappaB / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Previous studies have showed that photooxidative stress can lead to down-modulation of nuclear factor-kappa B (NF-kappaB) activity causing apoptosis of cultured photoreceptor cells. This study aimed at investigating whether NF-kappaB was involved in photoreceptor cells apoptosis induced by N-methyl-N-nitrosourea (MNU) in rats.</p><p><b>METHODS</b>A single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats. At different intervals after MNU treatment, the animals were sacrificed. Retinal damage was examined by a light microscope. The apoptotic index of the photoreceptor cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). NF-kappaB was analysed by Western blot and Transcriptin Factor Assay Kits.</p><p><b>RESULTS</b>The pyknosis of the photoreceptor nuclei and the disorientation of the outer segment of the photoreceptor layer was seen after MNU treatment for 24 hours. The outer nuclear layer and photoreceptor layer were almost completely lost at 7 days. Photoreceptor cells apoptosis reached the peaked value at 24 hours. In apoptotic cascade, the protein levels of NF-kappaB p65 were only detected after MNU treatment for 12 and 24 hours in the nucleus. Conversely, the amounts of IkappaBalpha were markedly increased in the cytoplasm as well as in the nucleus. The activity of NF-kappaB p65 in the nucleus was down-modulated in the end.</p><p><b>CONCLUSIONS</b>MNU-induced photoreceptor cell destruction was attributed to the apoptotic process by down-regulating the activation of NF-kappaB p65.</p>

Fine-structural details of the photoreceptor membranes in the ocellus of the scale-insect parasite Centrodora sp. (Hymenoptora; Aphenelidae): a case of gene transfer between host and parasite?

Only one insect (the scale insect Eriococcus sp.) is known, in which photoreceptive lamellae appear to have replaced the usual arthropod rhabdom microvilli. We are now reporting the presence of photoreceptive membranes, which also appear to resemble lamellae rather than microvilli, but they are in the ocellus of the tiny wasp Centrodora sp., which parasitizes scale insect eggs. The apparently optically homogenous lens of the Centrodora ocellus measures approximately 10 µm in diameter and, thus, operates at the limits of diffraction. We calculated that the lens is capable of focusing a parallel bundle of rays on the retina of the ocellus.

A search for homologues of plant photoreceptor genes and their signaling partners in the sugarcane expressed sequence tag (Sucest) database

A partir dos dados do projeto de sequenciamento de Ests da Cana de Açúcar (Sucest/FAPESP) e utilizando BLAST (tblastn) como ferramenta, foi realizada uma busca de genes homólogos aos elementos envolvidos nos processos de foto-recepçäo e já descritos para outras plantas, principalmente Arabidopsis. Foram obtidas altas identidades para os fitocromos A, B e C assim como para os críptocromos 1, 2 e a fototropina. Diversos elementos identificados como reguladores primários ou secundários na transduçäo de sinal de foto-receptores também foram identificados com baixos valores de E-value.

Resultados a largo plazo del tratamiento con filtro azul en pacientes con ambliopía estrábica / Long term results of the treatment with blue filter in patients with amblyopia estrábica

Objetivo: Evaluar el resultado del uso del Filtro azul (FA) a largo plazo en pacientes con ambliopía estrábica (AE) en cuanto al mejoramiento de la agudeza visual (AV), fijación y visión binocular (VB). Material y Método: Se estudiaron 39 pacientes con AE y AV <0.3 tratados con filtro azul a lo menos durante 6 meses y seguidos por 3 a 11 años. Se evaluó AV, fijación y VB. Resultados: Se logró mejorar la AV desde un promedio de 0.125 (1 m-0.3) a un promedio de 0.5 (0.1-1.0). 25 de los 39 pacientes lograron AV > a 0.5. De los 30 pacientes con fijación excéntrica (FE) se logró AV promedio final de 0.5. 14 pacientes bajaron su AV durante su seguimiento al interrumpir el tratamiento, la cual volvió a subir al reiniciarlo. La fijación inicial de los pacientes con FE en promedio fue macular, llegando en promedio a yuxtafoveal. Se logró VB de diferente grado en 17 de los 30 pacientes. Conclusión: El filtro azul es efectivo en mejorar la AV, fijación y VB a largo plazo en pacientes con AE. Es necesario seguir a los pacientes y en algunos casos mantener el tratamiento. La interrupción del tratamiento puede provocar disminución de AV y fijación logradas, que se recuperan al iniciar el tratamiento