RESUMEN
IMPORTANCE: Solar retinopathy is a rare form of retinal injury that occurs after direct sungazing. OBJECTIVE: To enhance understanding of the structural changes that occur in solar retinopathy by obtaining high-resolution in vivo en face images. DESIGN, SETTING, AND PARTICIPANT: Case report of a young adult woman who presented to the New York Eye and Ear Infirmary with symptoms of acute solar retinopathy after viewing the solar eclipse on August 21, 2017. MAIN OUTCOMES AND MEASURES: Results of comprehensive ophthalmic examination and images obtained by fundus photography, microperimetry, spectral-domain optical coherence tomography (OCT), adaptive optics scanning light ophthalmoscopy, OCT angiography, and en face OCT. RESULTS: The patient was examined after viewing the solar eclipse. Visual acuity was 20/20 OD and 20/25 OS. The patient was left-eye dominant. Spectral-domain OCT images were consistent with mild and severe acute solar retinopathy in the right and left eye, respectively. Microperimetry was normal in the right eye but showed paracentral decreased retinal sensitivity in the left eye with a central absolute scotoma. Adaptive optics images of the right eye showed a small region of nonwaveguiding photoreceptors, while images of the left eye showed a large area of abnormal and nonwaveguiding photoreceptors. Optical coherence tomography angiography images were normal in both eyes. En face OCT images of the right eye showed a small circular hyperreflective area, with central hyporeflectivity in the outer retina of the right eye. The left eye showed a hyperreflective lesion that intensified in area from inner to middle retina and became mostly hyporeflective in the outer retina. The shape of the lesion on adaptive optics and en face OCT images of the left eye corresponded to the shape of the scotoma drawn by the patient on Amsler grid. CONCLUSIONS AND RELEVANCE: Acute solar retinopathy can present with foveal cone photoreceptor mosaic disturbances on adaptive optics scanning light ophthalmoscopy imaging. Corresponding reflectivity changes can be seen on en face OCT, especially in the middle and outer retina. Young adults may be especially vulnerable and need to be better informed of the risks of viewing the sun with inadequate protective eyewear.
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Quemaduras Oculares/complicaciones , Angiografía con Fluoresceína/métodos , Epitelio Pigmentado Ocular/lesiones , Traumatismos por Radiación/complicaciones , Enfermedades de la Retina/etiología , Luz Solar/efectos adversos , Tomografía de Coherencia Óptica/métodos , Quemaduras Oculares/diagnóstico , Femenino , Fondo de Ojo , Humanos , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/efectos de la radiación , Traumatismos por Radiación/diagnóstico , Enfermedades de la Retina/diagnóstico , Campos Visuales , Adulto JovenRESUMEN
Blunt ocular trauma from a child's plastic foam-covered toy baseball bat caused traumatic optic neuropathy and choroidal rupture in a 9-year-old child. The examination revealed a visual acuity of 6/60, a relative afferent pupillary defect, optic nerve swelling, commotio retinae and retinal haemorrhages. There was no orbital fracture or intraorbital haematoma on CT scanning. Optical coherence tomography showed macular oedema and disruption of the retinal pigment epithelium and Bruch's membrane. The child was admitted for intravenous methylprednisolone and discharged on topical steroid treatment. At 1 month follow-up, visual acuity had improved to 6/12. Optic nerve swelling had resolved and the fundus had two crescent-shaped choroidal rupture scars. Choroidal rupture and optic neuropathy can be secondary to indirect trauma, and even when the mechanism of injury is with a piece of equipment designated as suitable for children, serious ocular injury can occur.
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Traumatismos en Atletas/etiología , Béisbol/lesiones , Coroides/lesiones , Seguridad de Productos para el Consumidor , Lesiones Oculares/etiología , Traumatismos del Nervio Óptico/etiología , Juego e Implementos de Juego/lesiones , Heridas no Penetrantes/etiología , Antiinflamatorios/administración & dosificación , Traumatismos en Atletas/diagnóstico , Lámina Basal de la Coroides/efectos de los fármacos , Lámina Basal de la Coroides/lesiones , Niño , Coroides/efectos de los fármacos , Ciclopentolato/administración & dosificación , Diagnóstico Diferencial , Quimioterapia Combinada , Lesiones Oculares/diagnóstico , Lesiones Oculares/tratamiento farmacológico , Angiografía con Fluoresceína , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Masculino , Metilprednisolona/administración & dosificación , Soluciones Oftálmicas , Traumatismos del Nervio Óptico/diagnóstico , Traumatismos del Nervio Óptico/tratamiento farmacológico , Epitelio Pigmentado Ocular/efectos de los fármacos , Epitelio Pigmentado Ocular/lesiones , Rotura , Tomografía de Coherencia Óptica , Tomografía Computarizada por Rayos X , Agudeza Visual/efectos de los fármacos , Heridas no Penetrantes/diagnóstico , Heridas no Penetrantes/tratamiento farmacológicoRESUMEN
PURPOSE: To examine the inner surface of the sclerotomy during microincision vitrectomy surgery by Miyake-Apple view. METHODS: The anterior half of porcine eyes was attached to a transparent acrylic plate with cyanoacrylate glue. Then, either a 23-gauge or a 25-gauge trocar-cannula was inserted through the sclera obliquely. The inner surface of the entrance site was observed posteriorly by Miyake-Apple view. These images were compared with the endoscopic view of two patients who underwent vitreous surgery for an epiretinal membrane. RESULTS: When the trocar-cannula was inserted obliquely, the Miyake-Apple view showed that the ciliary epithelium at the sclerotomy site was stretched. When the trocar-cannula was inserted vertically, the ciliary epithelium was folded, and the folds remained even after the trocar was removed. Vitreous strands were seen incarcerated into the sclerotomy site. In human eyes, a folding of the ciliary epithelium was not clearly seen with the endoscopic view but the incarcerated vitreous was seen. CONCLUSION: The Miyake-Apple view provided a precise, in vivo, observation of the inner surface of the entry site. It disclosed the morphological stress on the ciliary epithelium by the sclerotomy.
Asunto(s)
Cuerpo Ciliar/lesiones , Membrana Epirretinal/cirugía , Epitelio Pigmentado Ocular/lesiones , Esclerótica/cirugía , Esclerostomía/efectos adversos , Vitrectomía/efectos adversos , Animales , Cateterismo/instrumentación , Cateterismo/métodos , Endoscopía , Membrana Epirretinal/patología , Diseño de Equipo , Humanos , Microcirugia/efectos adversos , Microcirugia/instrumentación , Microcirugia/métodos , Esclerostomía/instrumentación , Esclerostomía/métodos , Estrés Mecánico , Porcinos , Vitrectomía/instrumentación , Vitrectomía/métodos , Cuerpo Vítreo/patología , Cuerpo Vítreo/cirugíaRESUMEN
AIM: To investigate whether retinal pigment epithelium (RPE)-choroid translocation would be a suitable treatment for RPE tears, which have a poor prognosis and are encountered more often since the introduction of anti-(vascular endothelial growth factor (VEGF)) therapy for exudative age-related macular degeneration (AMD). METHODS: Prospective interventional case series of six eyes of six patients with AMD with an RPE tear treated with an RPE-choroid translocation. The RPE tear occurred in a vascularised pigment epithelium detachment in four patients and after treatment in the other two. Preoperative and postoperative evaluation included ETDRS visual acuity (VA) and fixation testing. The follow-up period ranged from 6 months to 2 years. RESULTS: The mean preoperative VA was 20/160 (range 20/400-20/80). The mean VA at the last examination after surgery was 20/80 (range 1/60-20/50). One of the six patients had a preoperative VA of >/=20/80, and four had a VA of 20/80 or better at their last examination. Foveal fixation on the graft was present in five of the six eyes up to the last examination. CONCLUSION: These preliminary data show that an RPE-choroid translocation may be a treatment option for patients with an RPE tear.
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Coroides/trasplante , Epitelio Pigmentado Ocular/lesiones , Epitelio Pigmentado Ocular/trasplante , Anciano , Anciano de 80 o más Años , Neovascularización Coroidal/complicaciones , Neovascularización Coroidal/cirugía , Femenino , Humanos , Degeneración Macular/complicaciones , Masculino , Epitelio Pigmentado Ocular/patología , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del Tratamiento , Agudeza Visual , VitrectomíaRESUMEN
BACKGROUND: It has been shown that selective retina treatment (SRT) using a train of 1.7 microseconds laser pulses allows selective damage of the retinal pigment epithelium (RPE) while sparing the adjacent photoreceptors and thus avoiding laser scotoma. It was the purpose of this work to investigate SRT laser effects with Q-switched pulses of only 8 nanoseconds in duration by evaluating the angiographic and ophthalmoscopic damage thresholds and the damage range by histology in a rabbit model. MATERIALS AND METHODS: A flash lamp pumped frequency doubled (532 nm) Nd:YAG laser with 8 nanoseconds pulse duration was used. In total 210 laser lesions, each calculated to be 102 microm in diameter on retina, were applied through a slit lamp onto the fundus of six eyes of Chinchilla Bastard rabbits. The rabbits were irradiated with increasing energies with single pulses and a train of 10 laser pulses at 10 Hz. After treatment fundus photography and angiography were performed to determine the damage thresholds (ED(50)-probability of RPE cell damage and neurosensory retinal damage) as well as the safety range between both thresholds (ratio of angiographic ED(86) vs. ophthalmoscopic ED(14)). Selected histology was taken for single and repetitive pulse lesions after treatment. RESULTS: Angiographic and ophthalmoscopic ED(50)-thresholds decreased with increasing number of pulses. For single pulse application ophthalmoscopic and angiographic ED(50) were determined to 365 and 144 mJ/cm(2), respectively. Regarding 10 pulses 266 and 72 mJ/cm(2) were found. No retinal hemorrhages or disruptions were observed for both sets of parameters. The therapeutic window between angiographic and ophthalmoscopic threshold revealed a factor of 3.1 for single pulses and 2.3 for repetitive pulse irradiation. The safety range respectively had a factor of 0.8 (single pulses) and 1.7 (10 pulses). Histologic examination of laser lesions with single and repetitive pulses at radiant exposures within the therapeutic window-292 and 213 mJ/cm(2) respectively-revealed damaged RPE, intact Bruch's membrane and choriocapillaries. Photoreceptors were partly spared but also damaged to various extents. CONCLUSIONS: Short laser pulses of 8 nanoseconds pulse duration can damage the RPE without retinal hemorrhage or disruption. Selective damage of the RPE without affecting the photoreceptors can only rarely be achieved due to the small safety range. Thus, so far microsecond laser pulses for SRT seems favorable compared to nanosecond pulses in order to prevent unintentional photoreceptor damage.
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Coagulación con Láser/métodos , Epitelio Pigmentado Ocular/efectos de la radiación , Animales , Coagulación con Láser/efectos adversos , Epitelio Pigmentado Ocular/lesiones , Conejos , Factores de TiempoRESUMEN
PURPOSE: To detect retinal pigment epithelium (RPE) tears in predominantly classic choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) treated with intravitreal bevacizumab injections. METHODS: Forty consecutive patients with predominantly classic CNV secondary to AMD were treated with 1.25 mg of intravitreal bevacizumab. Patients were evaluated with visual acuity (VA) measured with Early Treatment Diabetic Retinopathy Study charts, optical coherence tomography, and fluorescein angiography. RESULTS: Three patients developed a RPE tear after the first injection. The first patient had been treated with verteporfin therapy and VA remained unchanged. In the other two cases the CNV was naive and VA improved since the foveal center was not involved by the tear and macular edema was reduced. CONCLUSIONS: RPE tears can occur following intravitreal bevacizumab injections in patients with predominantly classic CNV although VA is not always affected.
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Inhibidores de la Angiogénesis/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Neovascularización Coroidal/tratamiento farmacológico , Inyecciones/efectos adversos , Epitelio Pigmentado Ocular/lesiones , Perforaciones de la Retina/etiología , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados , Bevacizumab , Neovascularización Coroidal/etiología , Angiografía con Fluoresceína , Humanos , Degeneración Macular/complicaciones , Masculino , Epitelio Pigmentado Ocular/patología , Perforaciones de la Retina/diagnóstico , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual , Cuerpo VítreoRESUMEN
Solar maculopathy is caused by sun-gazing without protection and in most cases appears to be reversible. Retinal damage may be caused by photochemical changes combined with a rise in temperature at the time of sun observation. We report a case of bilateral solar retinopathy following direct sun gazing after observation of the partial eclipse on 3 October 2005. A 25-year-old Caucasian man presented 24 h after watching the eclipse with symptoms of blurred vision and a bright positive central scotoma. Total direct viewing time was approximately 5 min. While observing the eclipse, the patient kept both eyes open. On presentation, his visual acuity was 20/25 in his right eye and 20/32 in his left eye. Ophthalmoscopic examination revealed a bilateral yellowish-white spot in the center of the foveal region. Static visual field examination did not disclose any absolute scotoma but a decrease in the foveal threshold was noted in both eyes. Optical coherence tomography (OCT) examination revealed a bilateral increased reflectivity of the inner foveal retina that was greater in the left eye. This finding was associated with a hyporeflective area of the underlying retinal pigment epithelium: choriocapillaris complex and an increase in retinal thickness. Eight days later, visual acuity was 20/20 in each eye. Funduscopy showed the yellow lesion had vanished. Four months after exposure, funduscopy was normal and OCT scan showed normal reflectivity of all retinal layers in the fovea. However, static visual field examination disclosed a decreased foveal threshold on the left eye. We compare the OCT findings in this patient with the data reported in the literature. Indeed, various OCT findings have been reported depending on the intensity and frequency of sun exposure. This observation demonstrates that OCT appears to be potentially useful in the evolutive follow-up of solar maculopathy, and emphasizes the importance of eye safety during solar eclipse observation.
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Quemaduras Oculares/patología , Mácula Lútea/patología , Traumatismos por Radiación/patología , Enfermedades de la Retina/patología , Luz Solar/efectos adversos , Tomografía de Coherencia Óptica , Adulto , Quemaduras Oculares/etiología , Estudios de Seguimiento , Fóvea Central/lesiones , Fóvea Central/patología , Fóvea Central/efectos de la radiación , Humanos , Mácula Lútea/lesiones , Mácula Lútea/efectos de la radiación , Masculino , Oftalmoscopía , Epitelio Pigmentado Ocular/lesiones , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/efectos de la radiación , Traumatismos por Radiación/etiología , Remisión Espontánea , Enfermedades de la Retina/etiología , Escotoma/etiología , Escotoma/patología , Campos VisualesRESUMEN
PURPOSE: Selective targeting of the retinal pigment epithelium (RPE) with repetitive laser pulses that minimize thermal damage to the adjacent photoreceptors is a promising new therapeutic modality for RPE-related retinal diseases. The selectivity of an alternative, more versatile scanning approach was examined in vivo by using a broad range of scanning parameters. METHODS: Acousto-optic deflectors repeatedly scanned the focus of a continuous wave (cw)-laser across the retina of Dutch belted rabbits, producing microsecond irradiation at each RPE cell. Two irradiation patterns forming separated lines (SEP) or interlaced lines (INT), different dwell times (2.5-75 micros), and repetition numbers (10 and 100 scans with 100-Hz repetition rate) were tested. Thresholds were evaluated by fundus imaging and angiography. Histology was performed for selected parameters. RESULTS: Selective RPE cell damage was obtained with moderate laser power. The angiographic threshold power decreased with pulse duration, number of exposures, and applying the INT pattern. Ophthalmoscopic thresholds, indicating onset of thermal coagulation, were higher than twice the angiographic threshold for most tested parameters. Histology confirmed selective RPE cell damage for SEP irradiation with 7.5 and 15 micros; slower scan speeds or closed lines caused photoreceptor damage. CONCLUSIONS: A cw-laser scanner can be set up as a highly compact and versatile device. Selective RPE damage is feasible with dwell times up to 15 micros. Greatest selectivity is achieved with short exposure times and separated scan lines. Interlaced lines and long exposure times facilitate heat conduction into photoreceptors. A scanner is an attractive alternative for pulsed selective targeting, because both selective targeting and thermal photocoagulation can be realized.
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Coagulación con Láser/métodos , Epitelio Pigmentado Ocular/cirugía , Animales , Lesiones Oculares/diagnóstico , Angiografía con Fluoresceína , Coagulación con Láser/efectos adversos , Coagulación con Láser/instrumentación , Oftalmoscopía , Células Fotorreceptoras de Vertebrados/patología , Epitelio Pigmentado Ocular/lesiones , Epitelio Pigmentado Ocular/patología , Conejos , Retina/lesiones , Retina/patologíaAsunto(s)
Glucocorticoides/administración & dosificación , Inyecciones/efectos adversos , Epitelio Pigmentado Ocular/lesiones , Desprendimiento de Retina/tratamiento farmacológico , Perforaciones de la Retina/etiología , Triamcinolona Acetonida/administración & dosificación , Anciano , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/tratamiento farmacológico , Angiografía con Fluoresceína , Humanos , Masculino , Oftalmoscopía , Desprendimiento de Retina/diagnóstico , Cuerpo VítreoAsunto(s)
Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Epitelio Pigmentado Ocular/lesiones , Perforaciones de la Retina/inducido químicamente , Anciano , Anticuerpos Monoclonales Humanizados , Bevacizumab , Femenino , Humanos , Inyecciones , Degeneración Macular/tratamiento farmacológico , Tomografía de Coherencia Óptica , Cuerpo VítreoRESUMEN
The computer modeling was applied for investigation of the processes of laser-induced tissue damage. The melanin granule models for the processes of laser-induced thermal damage and the results of computer modeling of the optical, thermophysical, and thermochemical processes during selective laser interaction with melanoprotein granules (melanosomes) in retinal pigment epithelium are presented in this paper. Physical-mathematical model and system of equations are formulated which describe thermal interaction processes for "short" laser pulses of duration t (p)<10(-6) s and for " long' pulses of duration t(p) > 10(-6) s. Results of numerical simulation of the processes give the space-time distributions of temperature and degrees of thermodenaturation of the protein molecules inside and around melanosomes and in the volume of irradiated tissues. Energy absorption, heat transfer and thermochemical (thermodenaturation, coagulation) processes occurring during the interaction of laser pulses with pigmented spherical and spheroidal granules in heterogeneous tissues are theoretically investigated. The possibility for selective interaction of short laser pulses with pigmented granules is discussed which results in the formation of denaturation microregions inside and near the pigmented granules (granular thermodenaturation) without origination of a continuous macroscopic thermodenaturation lesion in tissue. Analytical model of heating of single spherical and spheroidal granule under laser pulse is presented. Simple equations for time dependencies of particle temperature are obtained. The presented results are of essential interest for laser applications in and can be used for investigation of laser interaction with pigmented tissues in different fields of laser medicine.
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Rayos Láser/efectos adversos , Melaninas/metabolismo , Melanosomas/efectos de la radiación , Modelos Biológicos , Epitelio Pigmentado Ocular/lesiones , Retina/lesiones , Simulación por Computador , Humanos , Melanosomas/metabolismoAsunto(s)
Epitelio Pigmentado Ocular/fisiología , Regeneración , Desprendimiento de Retina/metabolismo , Cicatrización de Heridas , Neovascularización Coroidal/etiología , Neovascularización Coroidal/cirugía , Angiografía con Fluoresceína , Humanos , Coagulación con Láser , Degeneración Macular/complicaciones , Masculino , Persona de Mediana Edad , Epitelio Pigmentado Ocular/lesiones , Recuperación de la Función , Desprendimiento de Retina/etiología , Rotura , Tomografía de Coherencia ÓpticaAsunto(s)
Contractura/complicaciones , Oftalmopatías/complicaciones , Lesiones Oculares/etiología , Epitelio Pigmentado Ocular/lesiones , Perforaciones de la Retina/etiología , Cuerpo Vítreo/patología , Lesiones Oculares/diagnóstico , Lesiones Oculares/cirugía , Angiografía con Fluoresceína , Traumatismos Cerrados de la Cabeza/diagnóstico , Traumatismos Cerrados de la Cabeza/cirugía , Humanos , Terapia por Láser , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Tomografía de Coherencia Óptica , Heridas no Penetrantes/diagnóstico , Heridas no Penetrantes/cirugíaAsunto(s)
Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Neovascularización Coroidal/tratamiento farmacológico , Degeneración Macular/complicaciones , Epitelio Pigmentado Ocular/lesiones , Anticuerpos Monoclonales Humanizados , Bevacizumab , Humanos , Inyecciones/efectos adversos , Masculino , Persona de Mediana EdadAsunto(s)
Lesiones Oculares/diagnóstico , Epitelio Pigmentado Ocular/lesiones , Desprendimiento de Retina/diagnóstico , Tomografía de Coherencia Óptica/métodos , Heridas no Penetrantes/diagnóstico , Accidentes por Caídas , Adulto , Lesiones Oculares/cirugía , Femenino , Humanos , Presión Intraocular , Coagulación con Láser , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/cirugía , Desprendimiento de Retina/cirugía , Agudeza Visual , Heridas no Penetrantes/cirugíaAsunto(s)
Lesiones Oculares/diagnóstico , Traumatismos Cerrados de la Cabeza/diagnóstico , Epitelio Pigmentado Ocular/lesiones , Perforaciones de la Retina/diagnóstico , Tomografía de Coherencia Óptica , Adulto , Lesiones Oculares/cirugía , Femenino , Angiografía con Fluoresceína , Traumatismos Cerrados de la Cabeza/cirugía , Humanos , Terapia por Láser , Perforaciones de la Retina/cirugíaAsunto(s)
Cuerpos Extraños en el Ojo/complicaciones , Lesiones Oculares Penetrantes/complicaciones , Hierro , Siderosis/etiología , Trastornos de la Visión/etiología , Enfermedad Aguda , Coroides/patología , Criocirugía , Electrorretinografía , Cuerpos Extraños en el Ojo/diagnóstico , Cuerpos Extraños en el Ojo/cirugía , Lesiones Oculares Penetrantes/diagnóstico , Lesiones Oculares Penetrantes/cirugía , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Epitelio Pigmentado Ocular/lesiones , Epitelio Pigmentado Ocular/patología , Complicaciones Posoperatorias/etiología , Siderosis/diagnóstico , Siderosis/cirugía , Ultrasonografía , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/cirugía , VitrectomíaRESUMEN
PURPOSE: To correlate changes in primate fundus after transpupillary thermotherapy (TTT) at two wavelengths. METHODS: Twelve primate eyes were treated with TTT using a wavelength of 635 nm (n=7) or 810 nm (n=5). Laser parameters were as follows: 635 nm (spot size, 1 mm; duration, 30-8 seconds; and fluence [power over time], 20-91.4 J/cm) and 810 nm (spot size, 2 mm; duration, 60 seconds; and fluence, 96-436 J/cm). Fundus photography, fluorescein and indocyanine green angiography, and enucleation were performed at time 0 or 2 weeks after TTT for histologic analysis. RESULTS: Threshold for fundus lesions (91.4 J/cm at 635 nm and 191 J/cm at 810 nm), acute and chronic retinal damage shown by histologic analysis (79.2 J/cm at 635 nm and 96 J/cm at 810 nm), and choroidal vessel occlusion (50 J/cm at 635 nm and 96 J/cm at 810 nm) were lower at 635 nm. Disorganization of the retina and retinal pigment epithelium was seen for both wavelengths at time 0 and 2 weeks after TTT. Occlusion of the choriocapillaris and choroidal stromal vessels was noted only in specimens obtained 2 weeks after TTT. CONCLUSIONS: TTT resulted in acute and delayed damage to the neurosensory retina that persisted at 2 weeks. The 635-nm wavelength demonstrated a lower threshold fluence for visible fundus lesions, retinal damage, and choroidal vascular occlusion than the 810-nm laser.
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Lesiones Oculares/etiología , Hipertermia Inducida/instrumentación , Rayos Láser/efectos adversos , Epitelio Pigmentado Ocular/lesiones , Retina/lesiones , Animales , Vasos Sanguíneos/ultraestructura , Coroides/irrigación sanguínea , Lesiones Oculares/patología , Angiografía con Fluoresceína , Verde de Indocianina , Macaca , Modelos Animales , Epitelio Pigmentado Ocular/ultraestructura , Pupila , Retina/ultraestructura , Umbral SensorialRESUMEN
PURPOSE: To investigate the cellular mechanisms involved in the cell death of human retinal pigment epithelial (hRPE) cells after their exposure to laser injury. METHODS: Cultured human hRPE cells were irradiated for different lengths of time and at different levels of energy using diode laser photocoagulation coupled with an intraocular laser probe. Apoptosis was determined by TUNEL staining and annexin-V labeling of phosphatidylserine exposure. Ceramide levels were quantified by the diacylglycerol kinase assay using thin-layer chromatography. RESULTS: Laser irradiation caused areas of apoptosis in the hRPE cells. These areas were detected around the ablated and necrotic laser scar and developed several hours after the laser irradiation. Laser irradiation concomitantly induced an increase in the intracellular production of ceramide, a lipid second messenger. CONCLUSIONS: The results demonstrate that laser irradiation induces apoptosis in hRPE cells and suggest that the underlying signaling mechanism involves ceramide generation.