Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 168
Filtrar
1.
Sci Rep ; 11(1): 16528, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-34400702

RESUMEN

Epithelial cysts run a high risk of recurrence and conversion to sheet-like ingrowth after surgical intervention. In this retrospective study, we introduced a modified iridectomy for treatment of secondary epithelial iris cysts (EICs) in the anterior chamber. Twenty-nine patients (29 eyes) aged 2-61 years received "open iridectomy" for EICs between April 1995 and July 2019. After viscodissection, most of the cyst wall was cut using a 20-gauge aspiration cutter via a 2.5-mm clear corneal incision. The residue closely adhering to the iris stroma was remained to avoid photophobia and diplopia. At 3 months, best corrected visual acuity was ≥ 20/100 in 55.5% (15/27, except two pediatric patients with poor cooperation) of patients. Among the eight patients suffering partial corneal edema preoperatively, six patients received surgery treatment at 3-6.5 months, and the cornea in the other two patients became transparent after medication. In a mean follow-up of 47.4 months, recurrence occurred in 3 patients at 7, 37, and 118 months, respectively. The percentage of treatment success was 96%, 87%, and 65% at 1, 5, and 10 years, respectively. "Open iridectomy" was effective for EICs, with a minimal invasion, less damage to the corneal endothelium, and a low recurrence rate.


Asunto(s)
Enfermedades Hereditarias del Ojo/cirugía , Iridectomía/métodos , Iris/anomalías , Epitelio Pigmentado Ocular/anomalías , Adolescente , Adulto , Cuidados Posteriores , Cámara Anterior/cirugía , Niño , Preescolar , Enfermedades Hereditarias del Ojo/etiología , Enfermedades Hereditarias del Ojo/patología , Lesiones Oculares Penetrantes/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Iris/patología , Iris/cirugía , Masculino , Persona de Mediana Edad , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/cirugía , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
3.
Arch. Soc. Esp. Oftalmol ; 92(3): 137-140, mar. 2017. ilus
Artículo en Español | IBECS | ID: ibc-160964

RESUMEN

CASO CLÍNICO: Presentamos el caso de un paciente varón de 39 años, con un hamartoma combinado de retina y epitelio pigmentario de retina. El paciente refería disminución progresiva de la visión y empeoramiento de la metamorfopsia. Se realizó una vitrectomía con pelado de la membrana epirretiniana, consiguiendo una mejoría de la agudeza visual y de la metamorfopsia, así como de la arquitectura retiniana en la tomografía de coherencia óptica. DISCUSIÓN: Algunos pacientes seleccionados con hamartomas combinados de retina y epitelio pigmentario podrían beneficiarse de la realización de una vitrectomía


CASE REPORT: The case is presented of a 39 year-old man with a combined hamartoma of the retina and retinal pigment epithelium, who experienced progressive visual loss and worsening of metamorphopsia. The patient underwent vitrectomy and epiretinal component peeling, with improvement in visual acuity, metamorphopsia, and retinal architecture, assessed by optical coherence tomography. DISCUSSION: Selected patients with combined hamartomas of the retina and retinal pigment epithelium may benefit from surgical management


Asunto(s)
Humanos , Masculino , Adulto , Hamartoma/cirugía , Retina/cirugía , Membrana Epirretinal/cirugía , Vitrectomía/métodos , Vitrectomía/tendencias , Epitelio Pigmentado Ocular/cirugía , Tomografía de Coherencia Óptica/instrumentación , Tomografía de Coherencia Óptica/métodos , Agudeza Visual/fisiología , Fondo de Ojo , Tomografía de Coherencia Óptica
4.
Acta Ophthalmol ; 94(7): e637-e643, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27130243

RESUMEN

PURPOSE: Adenomas of the ciliary pigment epithelium (CPE) are rare benign tumours which have mainly to be differentiated from malignant ciliary body melanomas. Here we report on a consecutive series of patients with CPE adenomas and describe their characteristics. METHODS: The retrospective hospital-based case series study included all patients who were consecutively operated for CPE adenomas. RESULTS: Of the 110 patients treated for ciliary body tumours, five patients (4.5%) had a CPE adenoma. Mean age was 59.0 ± 9.9 years (range: 46-72 years). Mean tumour apical thickness was 6.6 ± 1.7 mm. Tumour colour was mostly homogenously brown to black, and the tumour surface was smooth. The tumour masses pushed the iris tissue forward without infiltrating iris or anterior chamber angle. Sonography revealed an irregular echogram with sharp lesion borders and signs of blood flow in Color Doppler flow imaging. Ultrasonographic biomicroscopy demonstrated medium-low internal reflectivity and acoustic attenuation. In magnetic resonance imaging (MRI), the tumours as compared to brain were hyperintense on T1-weighted images and hypointense on T2-weighted images. Tumour tissue consisted of cords and nests of pigment epithelium cells separated by septa of vascularized fibrous connective tissue, leading to a pseudo-glandular appearance. The melanin granules in the cytoplasm were large and mostly spherical in shape. In four patients, the tumours were hyperpigmented. Tumour cells were large with round or oval nuclei and clearly detectable nucleoli. CONCLUSIONS: These clinical characteristics of CPE adenomas, such as homogenous dark brown colour, smooth surface, iris dislocation and anterior chamber angle narrowing but no iris infiltration, segmental cataract, pigment dispersion, and, as compared to brain tissue, hypointensity and, as compared to extraocular muscles or lacrimal gland, hyperintensity on T2-weighted MRI images, may be helpful for the differentiation from ciliary body malignant melanomas.


Asunto(s)
Adenoma/patología , Cuerpo Ciliar/patología , Epitelio Pigmentado Ocular/patología , Neoplasias de la Úvea/patología , Adenoma/diagnóstico por imagen , Adenoma/cirugía , Anciano , Cuerpo Ciliar/diagnóstico por imagen , Cuerpo Ciliar/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Microscopía Acústica , Persona de Mediana Edad , Procedimientos Quirúrgicos Oftalmológicos , Epitelio Pigmentado Ocular/diagnóstico por imagen , Epitelio Pigmentado Ocular/cirugía , Estudios Retrospectivos , Neoplasias de la Úvea/diagnóstico por imagen , Neoplasias de la Úvea/cirugía , Agudeza Visual
5.
Klin Oczna ; 116(1): 44-8, 2014.
Artículo en Polaco | MEDLINE | ID: mdl-25137922

RESUMEN

Iris cysts are rare lesions. In some cases, they may mimic melanoma and cause diagnostic difficulties. Through imaging tests such as ultrasound biomicroscopy we can evaluate the structure changes and determine the location for easy diagnosis. Iris cysts often require only observation. In some cases specialist treatment is necessary. One of the methods is transpupillary cystotomy perform using the Nd:YAG laser. The paper presents the case of familial pupillary cysts of the iris pigment epithelium in a father and a daughter.


Asunto(s)
Quistes/genética , Quistes/cirugía , Enfermedades del Iris/genética , Enfermedades del Iris/cirugía , Coagulación con Láser/métodos , Láseres de Estado Sólido/uso terapéutico , Epitelio Pigmentado Ocular/cirugía , Adulto , Niño , Quistes/diagnóstico por imagen , Quistes/patología , Femenino , Humanos , Enfermedades del Iris/diagnóstico por imagen , Enfermedades del Iris/patología , Masculino , Epitelio Pigmentado Ocular/diagnóstico por imagen , Epitelio Pigmentado Ocular/patología , Prevención Secundaria , Resultado del Tratamiento , Ultrasonografía
6.
Nippon Ganka Gakkai Zasshi ; 117(7): 554-7, 2013 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-23926815

RESUMEN

PURPOSE: To report a case of solitary pigment epithelial lesion accompanied by uveal effusion (UE) with bullous retinal detachment (RD). CASE: A 63-year-old man was referred to our hospital for RD in his right eye. Best corrected visual acuity was 20/20 and intraocular pressure was 14 mmHg in the right eye. Fundus examination showed UE in the entire peripheral zone with bullous RD in the inferior retina and a grayish-white placoid lesion with indistinct border at the level of the retinal pigment epithelium at the temporal area near the macula in the right eye. No retinal tear was found, and anterior chamber depth and axial length were within the normal range. Fluorescein angiography indicated dye leakage from the placoid lesion, but pooling of dye was not intensive. Since posterior scleritis was not excluded, a systemic corticosteroid was administered but the UE with bullous RD did not improve, thererfore, photocoagulation for the placoid lesion was performed. This gradually ameliorated the UE with bullous RD, and it resolved at 4 months after the first visit without any further recurrence. CONCLUSION: Solitary pigment epithelial lesion can cause UE with bullous RD as in multifocal posterior pigment epitheliopathy (MPPE).


Asunto(s)
Epitelio Pigmentado Ocular/cirugía , Desprendimiento de Retina/cirugía , Úvea/cirugía , Agudeza Visual/fisiología , Colorantes , Angiografía con Fluoresceína/métodos , Humanos , Masculino , Persona de Mediana Edad , Desprendimiento de Retina/complicaciones , Desprendimiento de Retina/diagnóstico
7.
Optom Vis Sci ; 90(4): e106-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23478631

RESUMEN

PURPOSE: To report a case of a peripheral pigment epithelium iris cyst treated with selective laser trabeculoplasty laser. CASE REPORT: A 15-year-old girl applied to our clinic with the complaint of painless blurred vision in the right eye. Gonioscopy through a widely dilated pupil revealed a clear, oval, pale brown, semitransparent cyst that was located in the inferotemporal aspect of the iris. The cyst was touching the lens, and the lens was pushed superonasally by the cyst. The iris cyst was treated with selective laser trabeculoplasty laser. A small iris notch emerged at the 8-o'clock position of the pupillary margin. Only mild flare and minimal pigment dispersion were documented postoperatively, which resolved in a few days with a topical corticosteroid. CONCLUSIONS: Selective laser trabeculoplasty laser may be considered as a potentially useful and relatively less invasive technique in the treatment of peripheral pigment epithelium iris cysts.


Asunto(s)
Quistes/cirugía , Enfermedades del Iris/cirugía , Terapia por Láser/métodos , Epitelio Pigmentado Ocular/cirugía , Trabeculectomía/métodos , Adolescente , Quistes/diagnóstico por imagen , Quistes/patología , Femenino , Gonioscopía , Humanos , Enfermedades del Iris/diagnóstico por imagen , Enfermedades del Iris/patología , Microscopía Acústica , Epitelio Pigmentado Ocular/diagnóstico por imagen , Epitelio Pigmentado Ocular/patología
8.
Ophthalmology ; 119(3): 634-41, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22197437

RESUMEN

PURPOSE: To report the clinical and histopathologic findings associated with congenital fibrovascular pupillary membranes. DESIGN: Case series. PARTICIPANTS: Seven infants were included, 6 with a unilateral congenital pupillary membrane and 1 with classic persistent fetal vasculature (PFV). METHODS: Patients underwent a membranectomy, pupilloplasty, or lensectomy. Histopathologic examination was performed on the excised membranes. MAIN OUTCOME MEASURES: Visual acuity and pupil size. RESULTS: Four of the 6 patients with a unilateral congenital pupillary membrane had 1 or more recurrences after a membranectomy and pupilloplasty. The most recent pupil size ranged from 2 to 5 mm in the affected eye. When last tested, the vision in the affected eye was excellent in 4 of the 6 patients. The 2 patients without recurrences of the pupillary membranes underwent multiple iris sphincterotomies at the time of the initial surgery. Histopathologic examination of 2 primary pupillary membranes showed fibrovascular tissue that did not stain for neuron-specific enolase. Smooth muscle actin was only present in vascular walls. In contrast, histopathology of a recurrent pupillary membrane revealed collagenized fibrovascular tissue that was immunoreactive for smooth muscle actin. Finally, histopathology of the retrolenticular membrane excised from an infant with classic PFV was similar to the latter aside from hypercellularity. CONCLUSIONS: Congenital fibrovascular pupillary membranes in infants are likely a variant of PFV that may recur if incompletely excised. The risk of these membranes recurring may be reduced by excising as much as the membrane as possible and enlarging the pupil with iris sphincterotomies. A lensectomy should be avoided if possible.


Asunto(s)
Iris/irrigación sanguínea , Vítreo Primario Hiperplásico Persistente/patología , Epitelio Pigmentado Ocular/patología , Trastornos de la Pupila/congénito , Femenino , Humanos , Lactante , Recién Nacido , Membranas/irrigación sanguínea , Membranas/patología , Membranas/cirugía , Procedimientos Quirúrgicos Oftalmológicos , Vítreo Primario Hiperplásico Persistente/cirugía , Epitelio Pigmentado Ocular/cirugía , Trastornos de la Pupila/patología , Trastornos de la Pupila/cirugía , Recurrencia
9.
Klin Monbl Augenheilkd ; 225(4): 259-68, 2008 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-18401791

RESUMEN

The scientific background of laser photocoagulation of the ocular fundus was studied extensively by several investigators in the 1970 s and 1980 s. The basic principles were successfully resolved during that time and clinical consequences for proper application of the laser photocoagulation for various diseases were deduced. The present paper gives an overview about the physical basics of laser-tissue interactions during and after retinal laser treatment and the particular laser strategies in the treatment of different retinal diseases. Thus, it addresses the issue of the impact on tissue of laser parameters as wavelength, spot size, pulse duration and laser power. Additionally, the different biological tissue reactions after laser treatment are presented, such as, e. g., for retinopexia or macular treatments as well as for diabetic retinopathies. Specific laser strategies such as the selective laser treatment of the RPE (SRT) or the transpupillary thermotherapy (TTT) are presented and discussed.


Asunto(s)
Fotocoagulación/métodos , Enfermedades de la Retina/cirugía , Coroides/patología , Coroides/cirugía , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/cirugía , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/cirugía , Angiografía con Fluoresceína , Humanos , Mácula Lútea/patología , Mácula Lútea/cirugía , Oftalmoscopía , Papiledema/cirugía , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Retina/patología , Retina/cirugía , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Drusas Retinianas/cirugía , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía
10.
Harefuah ; 147(2): 131-3, 182, 2008 Feb.
Artículo en Hebreo | MEDLINE | ID: mdl-18357669

RESUMEN

BACKGROUND: Cyclophotoablation for glaucoma treatment is dependent on the amount of laser energy absorbed by the ciliary body and related to the degree of its pigmentation. Iris color may be assessed by observing the eye, but it is unknown whether it correlates with ciliary body pigmentation. AIM: We evaluated whether ciliary pigmentation correlates with iris color. METHODS: The pigmented epithelium of the ciliary processes of 31 enucleated eyes was qualitatively scored for six histological parameters and correlated with iris color. RESULTS: The dark iris group (n = 19) had significantly increased histological parameters of pigmentation such as aggregation of melanosomes, compared to the light iris group (n = 12) (p < 0.01). CONCLUSION: Iris color correlates with ciliary pigmentation and may serve as one of the factors determining laser power needed for cyclophotoablation.


Asunto(s)
Cuerpo Ciliar/fisiología , Cirugía Laser de Córnea , Color del Ojo/fisiología , Iris/fisiología , Terapia por Láser , Epitelio Pigmentado Ocular/fisiología , Enucleación del Ojo , Humanos , Iris/patología , Iris/cirugía , Melanosomas/fisiología , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/cirugía
12.
Eye (Lond) ; 22(9): 1099-104, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17641680

RESUMEN

OBJECTIVE: To analyse the long-term results of surgical removal of plaque-like diabetic foveal hard exudates. METHODS: In this retrospective, interventional, non-randomized, controlled study, vitrectomy and excision of submacular hard exudates was performed on 11 eyes of 11 patients with plaque-like hard exudates. The mean preoperative LogMAR best corrected visual acuity (BCVA) and exudate diameter were 1.35+/-0.3 and 1.19 disks (range, 0.5-1.8), respectively. In the control group, which consisted of 10 eyes of 7 patients who refused the surgery, baseline mean BCVA and exudate diameter were 1.06+/-0.2 and 1.2 disks (range, 0.7-2.0), respectively. Main outcome measures included BCVA, fundus photography, and surgical complications. RESULTS: The mean follow-up was 39.1+/-3.2 months for the study group and 32.5+/-3.6 months for the control group. In the study group, BCVA improved in 8 (73%) eyes at the final examination. The mean final BCVA was 1.08+/-0.4 (P=0.021). Macular oedema and exudates resolved completely in all eyes. In the control group, final LogMAR visual acuity declined to 1.53+/-0.1 (P=0.005). Macular pigment epithelium atrophy or scar formation was observed in 7 (64%) eyes in the study group and in all eyes in the control group. CONCLUSION: Surgical excision of plaque-like foveal hard exudates resulted in better anatomical and functional outcome when compared to observation alone.


Asunto(s)
Retinopatía Diabética/cirugía , Fóvea Central/cirugía , Edema Macular/cirugía , Epitelio Pigmentado Ocular/cirugía , Anciano , Retinopatía Diabética/etiología , Exudados y Transudados , Femenino , Estudios de Seguimiento , Fóvea Central/fisiopatología , Humanos , Edema Macular/complicaciones , Masculino , Persona de Mediana Edad , Epitelio Pigmentado Ocular/fisiopatología , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual
13.
Int Ophthalmol ; 28(5): 359-62, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17898938

RESUMEN

PURPOSE: To describe the natural course of subretinal triamcinolone acetonide (TA) deposition after a TA-assisted vitrectomy for retinal detachment. METHODS: Observational case series. RESULTS: TA deposition was observed between the neurosensory retina and retinal pigment epithelium in the macular area at the conclusion of vitreoretinal surgery in three patients with retinal detachment. On follow up, TA granules gradually decreased over the next 2 weeks and resolved completely by 3 weeks. Two months after the operation, the retina was observed to be successfully attached and no ophthalmoscopic or functional damage was observed. CONCLUSION: As no apparent clinically detectable adverse effect was found in the three cases that demonstrated subretinal deposition of TA we opine that active surgical maneuvers to remove the same are not warranted during surgery.


Asunto(s)
Glucocorticoides/efectos adversos , Granuloma de Cuerpo Extraño/etiología , Enfermedades de la Retina/etiología , Triamcinolona Acetonida/efectos adversos , Vitrectomía , Adolescente , Adulto , Preescolar , Estudios de Seguimiento , Humanos , Masculino , Epitelio Pigmentado Ocular/cirugía , Desprendimiento de Retina/cirugía
15.
Retina ; 27(5): 629-34, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17558327

RESUMEN

PURPOSE: To evaluate production of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) after panretinal photocoagulation (PRP) of human retinal pigment epithelium (RPE) explants. METHODS: Treated explants were subjected to substrate zymography to differentiate MMP-2 from MMP-9 and dot immunoblot analysis to quantify MMP-3 and TIMP activity. Tritiated thymidine uptake by RPE cells was measured to document evidence of cellular division in the laser-treated versus control explants. RESULTS: We detected MMP-2, MMP-3, and TIMP-1. MMP-2 and MMP-3 secretion increased to twice the control values. TIMP decreased until day 4 and then increased by day 6. Tritiated thymidine uptake increased 2.5-fold until day 6, returning to baseline by day 8. CONCLUSION: PRP disturbs MMP/TIMP balance, inhibiting the initiation and maintenance required for active neovascularization. The efficacy of PRP may be due to changes in the expression pattern of metalloproteinases and inhibitors. This model elucidates the possible contribution of PRP to neovascularization regression by demonstrating the effect of laser on TIMP/MMP balance. The effects of PRP may be much more complex than currently understood and most likely involve more than vascular endothelial growth factor and other ischemia-related factors.


Asunto(s)
Coagulación con Láser , Metaloproteinasas de la Matriz/biosíntesis , Epitelio Pigmentado Ocular/enzimología , Epitelio Pigmentado Ocular/cirugía , Anciano , Western Blotting , División Celular , Electroforesis en Gel de Poliacrilamida , Humanos , Persona de Mediana Edad , Técnicas de Cultivo de Órganos , Inhibidores Tisulares de Metaloproteinasas/biosíntesis
16.
Klin Monbl Augenheilkd ; 224(4): 356-9, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17458814

RESUMEN

BACKGROUND: Combined hamartoma of the retina and retinal pigment epithelium (CHRRPE) are rare, benign tumours that typically appear slightly elevated and are characterised by varying amounts of pigmentation, vascular tortuosity, and epiretinal membrane formation that can be related to macular distortion. The importance of changes at the vitreoretinal interface in this condition as a risk for visual loss was early recognised but controversy exists concerning the benefits of surgical removal of the tractional component. We describe 2 cases of CHRRPE who demonstrated significant visual acuity improvement after pars plana vitrectomy and epiretinal membrane peeling. HISTORY AND SIGNS: A 12-year-old girl and a 14-year-old boy presented with progressive unilateral visual loss related with a CHRRPE. In both instances the hamartoma was associated with a thickened posterior hyaloid and epiretinal membrane inducing considerable vitreomacular traction as shown by optical coherence tomography (OCT). Best-corrected pre-operative visual acuity was 0.2 in both cases. THERAPY AND OUTCOME: Vitrectomy and epiretinal membrane peeling were performed in both cases. Relief of vitreomacular traction and macular distortion was achieved and documented on OCT. Visual acuity at the latest follow up was 0.5 and 0.8, respectively. CONCLUSIONS: Surgical dissection can be effective in the treatment of vitreomacular traction associated with CHRRPE with a good functional and anatomical outcome.


Asunto(s)
Membrana Epirretinal/cirugía , Hamartoma/cirugía , Epitelio Pigmentado Ocular/cirugía , Enfermedades de la Retina/cirugía , Vitrectomía/métodos , Vitreorretinopatía Proliferativa/cirugía , Adolescente , Niño , Femenino , Humanos , Masculino , Resultado del Tratamiento
17.
Invest Ophthalmol Vis Sci ; 48(4): 1782-92, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17389512

RESUMEN

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.


Asunto(s)
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/patología
18.
Graefes Arch Clin Exp Ophthalmol ; 245(8): 1189-98, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17219108

RESUMEN

PURPOSE: To develop a reproducible surgical technique for the induction of choroidal neovascularization (CNV) in the subretinal space of porcine eyes and to analyse the resulting CNV clinically and histologically. METHODS: Two different modifications of a surgical technique previously described were compared with the original method. In ten porcine eyes retinal pigment epithelial (RPE) cells were removed using a silicone tipped cannula, in ten porcine eyes Bruch's membrane was perforated once with a retinal perforator without prior RPE removal and in ten eyes RPE removal was followed by a single perforation of Bruch's membrane. Fifteen of the eyes, five from each group, were enucleated 30 minutes after surgery, while the remaining eyes were enucleated after 14 days. Prior to enucleation, at day 14, fundus photographs and fluorescein angiograms were obtained. Eyes were examined by light microscopy and by immunohistochemical staining. In addition to these 30 eyes, two eyes underwent surgery with the purpose of subsequent scanning electron microscopic (SEM) examination. RESULTS: In eyes enucleated immediately after surgery neuroretinas overlying the induced lesions were intact without apparent atrophy of cells regardless of the surgical technique applied. The process of RPE removal was found to induce breaks in Bruch's membrane and both the size and the number of breaks varied between eyes. CNV membranes were identified in 15 of 15 eyes enucleated after 14 days. CNV membranes induced by perforation of Bruch's membrane without prior RPE removal were significantly thicker than membranes from eyes undergoing both RPE removal and Bruch's perforation (p = 0.03) and also thicker than membranes from eyes with only RPE-removal (p < 0.01). CNV membranes from eyes with perforation of Bruch's membrane without prior RPE removal had a higher cellular content and were more richly vascularized and also exhibited the highest propensity to leak in fluorescense angiograms. CONCLUSION: All three surgical techniques were capable of inducing CNV, but the one applying perforation of Bruch's membrane without RPE removal was easier to reproduce and involved fewer variables than the techniques utilizing RPE removal. The presence of RPE cells seems to affect both the morphology and cellular composition of induced CNV.


Asunto(s)
Neovascularización Coroidal/etiología , Modelos Animales de Enfermedad , Procedimientos Quirúrgicos Oftalmológicos , Animales , Lámina Basal de la Coroides/lesiones , Neovascularización Coroidal/patología , Enucleación del Ojo , Angiografía con Fluoresceína , Técnicas para Inmunoenzimas , Microscopía Electrónica de Rastreo , Epitelio Pigmentado Ocular/cirugía , Rotura , Porcinos
19.
J Biomed Opt ; 12(6): 064034, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18163850

RESUMEN

Selective laser targeting of the retinal pigment epithelium (RPE) is an attractive method for treating RPE-associated disorders. We are developing a method for optically detecting intracellular microcavitation that can potentially serve as an immediate feedback of the treatment outcome. Thermal denaturation or intracellular cavitation can kill RPE cells during selective targeting. We examined the cell damage mechanism for laser pulse durations from 1 to 40 micros ex vivo. Intracellular cavitation was detected as a transient increase in the backscattered treatment beam. Cavitation and cell death were correlated for individual cells after single-pulse irradiation. The threshold radiant exposures for cell death (ED(50,d)) and cavitation (ED(50,c)) increased with pulse duration and were approximately equal for pulses of up to 10 micros. For 20 micros, the ED(50,d) was about 10% lower than the ED(50,c); the difference increased with 40-micros pulses. Cells were killed predominantly by cavitation (up to 10-micros pulses); probability of thermally induced cell death without cavitation gradually increases with pulse duration. Threshold measurements are discussed by modeling the temperature distribution around laser-heated melanosomes and the scattering function from the resulting cavitation. Detection of intracellular cavitation is a highly sensitive method that can potentially provide real-time assessment of RPE damage during selective laser targeting.


Asunto(s)
Terapia por Láser/métodos , Epitelio Pigmentado Ocular/cirugía , Animales , Bovinos , Muerte Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Técnicas In Vitro , Monitoreo Fisiológico , Óptica y Fotónica , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/efectos de la radiación , Enfermedades de la Retina/patología , Enfermedades de la Retina/cirugía , Dispersión de Radiación , Temperatura
20.
Br J Ophthalmol ; 91(2): 248-52, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16987899

RESUMEN

AIM: To study the histological effects of trans-scleral cyclophotocoagulation (TCP) and endoscopic cyclophotocoagulation (ECP) on the ciliary body and other structures collected at autopsy and to compare with untreated controls. MATERIALS AND METHODS: TCP and ECP were performed on human eyes at autopsy. Detailed histological evaluations were perfomed using light microscopy and scanning electron microscopy on treated eyes and compared with untreated controls. RESULTS: Histological changes were observed with both light microscopy and scanning electron microscopy for all treated tissues. Tissue treated with TCP showed pronounced tissue disruption of the ciliary body muscle and stroma, ciliary processes, and both pigmented and non-pigmented ciliary epithelium. ECP-treated tissue exhibited pronounced contraction of the ciliary processes with disruption of the ciliary body epithelium, sparing of the ciliary body muscle and less architectural disorganisation. The sclera was not affected by either laser treatment. CONCLUSIONS: ECP treatment caused less damage to the ciliary body compared with TCP when evaluated by light microscopy and scanning electron microscopy. Compared with TCP, ECP seems to be a more selective form of cyclophotocoagulation, resulting in less tissue disruption while achieving the goal of destroying ciliary body epithelium.


Asunto(s)
Ojo/patología , Coagulación con Láser/métodos , Autopsia , Cuerpo Ciliar/cirugía , Cuerpo Ciliar/ultraestructura , Endoscopía , Humanos , Coagulación con Láser/instrumentación , Microscopía Electrónica de Rastreo , Epitelio Pigmentado Ocular/cirugía , Epitelio Pigmentado Ocular/ultraestructura
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...