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1.
Clin Exp Optom ; : 1-6, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37844333

RESUMEN

CLINICAL RELEVANCE: Currently eye examinations are usually based on autorefraction followed by subjective refraction (SR) with a phoropter. An automated phoropter that can also perform autorefraction may facilitate the optometric workflow. BACKGROUND: The efficiency and feasibility of an objective autorefraction and correction system are assessed by comparing objective refractive measurements with SR on the same subjects and evaluating the visual acuity (VA) values obtained after the objective refractive measurement and correction. METHODS: Objective autorefraction and correction was performed on 41 subjects using an automated binocular phoropter system. The auto-phoropter performs autorefraction by wavefront measurement and corrects the spherical and cylindrical errors with tunable fluidic lenses while the patient looks at a visual display inside the instrument. The instrument outputs are optometric constants of spherical and cylindrical aberrations. After measurement and automated correction of the refractive errors, the VA values were assessed by having the subjects look at an integrated Snellen chart. The objective measurement results were statistically compared with their SR. RESULTS: The correlations between SR and objective autorefraction and correction spherical equivalents (M) were 0.98 (0.97-0.99) and 0.96 (0.93-0.98), the vertical Jackson cross cylinder (J0) were 0.96 (0.92-0.98) and 0.95 (0.91-0.97), and the oblique Jackson cross cylinder (J45) were 0.73 (0.55-0.85) and 0.82 (0.69-0.90), for the right and left eyes, respectively, with the 95% confidence interval (CI) values in parentheses. 89.0% of the 82 eyes had at least 6/7.5 VA. CONCLUSIONS: A significant agreement between the SR and objective autorefraction and correction was observed. An all-objective refractive assessment with instantaneous verification may improve the precision of eye prescriptions and possibly reduce the procedure time.

2.
Clin Ophthalmol ; 12: 2223-2235, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30464383

RESUMEN

Cataract surgery is one of the most commonly performed surgeries worldwide, with nearly 20 million cases annually. Appropriate prophylaxis after cataract surgery can contribute to a safe and quick visual recovery with high patient satisfaction. Despite being the current standard of care, the use of multiple postoperative eye drops can create a significant burden on these patients, contributing to documented and significant non-adherence to the postoperative regimen. Over the past 25 years, there have been a few studies analyzing the use of intracameral dexamethasone (DXM) in controlling inflammation following cataract surgery. This review explores various drug delivery approaches for managing intraocular inflammation after cataract surgery, documenting the strengths and weaknesses of these options and examining the role of intracameral DXM (among these other strategies) in controlling postoperative intraocular inflammation. Intracameral DXM has a particular advantage over topical steroids in possibly decreasing postoperative inflammatory symptoms and objective anterior cell and flare scores. Compared to topical steroids, there may be a slightly less theoretical risk of significant intraocular pressure spikes and systemic absorption. In addition, surveys indicate patients prefer an intraoperative intracameral injection over a self-administered postoperative eye drop regimen. However, there are several adverse effects associated with intracameral DXM delivery that are not seen with the noninvasive topical approach. Although it is unlikely that intracameral DXM will replace topical medications as the standard management for postoperative inflammation, it is seemingly another safe and effective strategy for controlling postoperative inflammation after routine cataract surgery.

3.
J Ophthalmic Vis Res ; 13(2): 91-92, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29719634
4.
Curr Opin Ophthalmol ; 29(1): 69-74, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29095715

RESUMEN

PURPOSE OF REVIEW: This review is timely because the outcomes of surgical invention in uveitic eyes with cataract can be optimized with adherence to strict anti-inflammatory principles. RECENT FINDINGS: All eyes should be free of any cell/ flare for a minimum of 3 months preoperatively. Another helpful maneuver is to place dexamethasone in the infusion fluid or triamcinolone intracamerally at the end of surgery. Recent reports about the choice of intraocular lens material or lens design are germane to the best surgical outcome. Integrating these findings will promote better visual outcomes and allow advancement in research to further refine these surgical interventions in high-risk uveitic eyes. SUMMARY: Control of inflammation has been shown to greatly improve postoperative outcomes in patients with uveitis. Despite better outcomes, more scientific research needs to be done regarding lens placement and materials and further research needs to adhere to the standardized reporting of uveitis nomenclature. Future studies should improve postoperative outcomes in eyes with uveitis so that they approach those of eyes undergoing routine cataract procedures.


Asunto(s)
Antiinflamatorios/uso terapéutico , Extracción de Catarata/métodos , Catarata/complicaciones , Manejo de la Enfermedad , Uveítis/complicaciones , Femenino , Humanos , Uveítis/tratamiento farmacológico , Agudeza Visual
5.
Retin Cases Brief Rep ; 11(2): 95-99, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-26934303

RESUMEN

PURPOSE: Central serous chorioretinopathy (CSR) is a serous detachment of the neurosensory retina commonly associated with male sex, Type-A personality and corticosteroid use. Exogenous administration of androgens and development of CSR in men has been reported. Only one case of CSR in a postmenopausal woman receiving exogenous androgen therapy has been reported. The authors describe three cases of chronic CSR in postmenopausal women receiving exogenous testosterone therapy. METHODS: Diagnosis was based on characteristic clinical, fluorescein angiographic, and optical coherence tomography findings. The three women were being treated with exogenous testosterone and progesterone therapy for symptoms of menopause and libido loss. RESULTS: Average age at presentation was 54.7 years (53-56 years), average duration of exogenous androgen use was 61 months (36-87 months), with average 19.7-month follow-up. Resolution of symptoms seemed correlated with cessation of androgen use despite treatment with oscillatory photodynamic therapy and intravitreal pharmacotherapy with antivascular endothelial growth factor agents. CONCLUSION: Exogenous testosterone is increasingly prescribed for menopausal symptoms and libido loss. Treatment with oscillatory photodynamic therapy, supplemental bevacizumab intravitreal pharmacotherapy, and cessation of exogenous androgen therapy was successful in three cases of chronic, therapy-resistant CSR. Ophthalmologists should inquire about androgen usage in patients who present with CSR, especially in the setting of therapy resistance.


Asunto(s)
Andrógenos/efectos adversos , Coriorretinopatía Serosa Central/inducido químicamente , Testosterona/efectos adversos , Femenino , Humanos , Persona de Mediana Edad
6.
Ophthalmol Retina ; 1(2): 103-110, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31047266

RESUMEN

PURPOSE: To compare the efficacy of 2 doses of intravitreal ziv-aflibercept (IVZ) with intravitreal bevacizumab (IVB) in the treatment of center-involved diabetic macular edema (DME) at 12 weeks. DESIGN: Three-armed, double-blind, randomized clinical trial. PARTICIPANTS: Eyes with center-involved DME. METHODS: In this trial, 123 eyes with DME were randomly assigned to 3 injections of 1.25 mg IVZ, 2.5 mg IVZ, and 1.25 mg IVB every 4 weeks. Complete ophthalmologic examination and central macular thickness (CMT) measurement by optical coherence tomography were performed every 4 weeks up to 12 weeks. MAIN OUTCOME MEASURES: Change in best-corrected visual acuity (BCVA) at 12 weeks. RESULTS: Although no significant difference was evident between the 2 ziv-aflibercept groups at 12 weeks, the BCVA change was significantly better in the ziv-aflibercept 1.25 mg group than in the IVB group at the 12-week visit (P = 0.021). In regard to CMT changes, there was no significant difference between the 2 ziv-aflibercept groups; however, a significantly greater reduction in CMT was observed in the ziv-aflibercept 2.5 mg group compared with the IVB group at 12 weeks (P = 0.037). Subgroup analysis disclosed no difference in BCVA outcomes at 12 weeks among the groups in the eyes with baseline BCVA ≥20/50. In the eyes with baseline BCVA <20/50, the improvement was significantly better at 12 weeks in the ziv-aflibercept 1.25 mg group compared with the IVB group (P = 0.011). CONCLUSIONS: The 12-week results of this trial disclosed that both 1.25 mg and 2.5 mg doses of IVZ and IVB demonstrated BCVA improvement over baseline in the treatment of center-involved DME. However, a stronger effect of IVZ compared with IVB in terms of both visual acuity improvement and macular thickness reduction was detected in the eyes with initial BCVA <20/50. Longer-term efficacy and safety data will be needed to understand the role for this drug in practice.

7.
Acta Ophthalmol ; 95(8): e668-e676, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27864881

RESUMEN

Alzheimer's disease (AD) is an increasingly common disease with massive personal and economic costs. While it has long been known that AD impacts the visual system, there has recently been an increased focus on understanding both pathophysiological mechanisms that may be shared between the eye and brain and how related biomarkers could be useful for AD diagnosis. Here, were review pertinent cellular and molecular mechanisms of AD pathophysiology, the presence of AD pathology in the visual system, associated functional changes, and potential development of diagnostic tools based on the visual system. Additionally, we discuss links between AD and visual disorders, including possible pathophysiological mechanisms and their relevance for improving our understanding of AD.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Ojo/diagnóstico por imagen , Neuroimagen/métodos , Trastornos de la Visión , Agudeza Visual , Corteza Visual/fisiopatología , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/fisiopatología , Ojo/fisiopatología , Humanos , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología , Trastornos de la Visión/fisiopatología , Corteza Visual/diagnóstico por imagen
8.
Ophthalmic Surg Lasers Imaging Retina ; 46(5): 593-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26057767

RESUMEN

A 65-year-old woman with left hemiparesis and sudden loss of visual acuity in her right eye presented a few hours after cosmetic injection of autologous fat to her forehead. Right eye visual acuity was no light perception. Funduscopy revealed widespread retinal whitening and multibranch retinal vessel occlusion. Fluorescein angiography showed markedly delayed choroidal and retinal filling together with occlusion of multiple branches of retinal arteries and veins. On magnetic resonance imaging of the brain, multiple lesions compatible with recent infarction were detected. The authors diagnosed multibranch retinal artery and vein occlusion in the right ophthalmic and middle cerebral arteries due to fat emboli. This case emphasizes the need to reevaluate the safety of such aesthetic procedures, particularly in the facial zone to prevent devastating complications.


Asunto(s)
Arteriopatías Oclusivas/etiología , Frente , Arteria Cerebral Media/patología , Arteria Oftálmica/patología , Vasos Retinianos/patología , Grasa Subcutánea/trasplante , Cirugía Plástica/efectos adversos , Anciano , Arteriopatías Oclusivas/diagnóstico , Embolia Grasa/etiología , Femenino , Angiografía con Fluoresceína , Humanos , Ritidoplastia , Tomografía de Coherencia Óptica , Trasplante Autólogo
9.
Int Ophthalmol ; 35(3): 421-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25037243

RESUMEN

The purpose of the study is to compare single injection of intravitreal diclofenac (IVD) with intravitreal bevacizumab (IVB) in the treatment of eyes with naïve diabetic macular edema (DME). In this randomized clinical trial, 57 eyes of 57 patients were randomly assigned to IVD group (30 eyes), cases who received a single intravitreal injection of diclofenac (500 µg/0.1 ml), and IVB group (27 eyes), cases who received a single intravitreal injection of bevacizumab (1.25 mg). Change in best-corrected visual acuity in logMAR at week 12 was the primary outcome measure. Secondary outcomes included changes in central macular thickness, macular leakage, and potential injection-related complications. Best-corrected visual acuity improved significantly more in the IVD group than in the IVB group (P = 0.033), from 0.57 ± 0.25 to 0.49 ± 0.31 versus 0.55 ± 0.24-0.59 ± 0.27 logMAR at 12 weeks, respectively. However, the difference of macular thickness changes was in favor of IVB, but not to a significant level. The amount of change in leakage was not significantly different between the groups either. None of the eyes, in either group, developed ocular hypertension (≥23 mmHg) or cataract progression. No important injection-related complication was observed during the study period. This study demonstrated the superiority of IVD over IVB in the treatment of naïve DME regarding functional, but not anatomical outcomes. Therefore, using IVD as an adjunct or even alternative to other treatments might enhance the functional outcomes in such cases. Further studies are warranted to confirm potential benefit of IVD observed in this study.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Antiinflamatorios no Esteroideos/administración & dosificación , Bevacizumab/administración & dosificación , Retinopatía Diabética/tratamiento farmacológico , Diclofenaco/administración & dosificación , Edema Macular/tratamiento farmacológico , Adulto , Anciano , Análisis de Varianza , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravítreas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Agudeza Visual
10.
J Ophthalmic Vis Res ; 9(4): 453-60, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25709771

RESUMEN

PURPOSE: To compare the efficacy of intravitreal bevacizumab (IVB) injection alone or with intravitreal triamcinolone acetonide (IVB/IVT) versus macular photocoagulation (MPC) in bilateral diabetic macular edema (DME). METHODS: In this study we revisited data from a subset of subjects previously enrolled in a randomized clinical trial. The original study included 150 eyes randomized to three treatment arms: 1.25 mg IVB alone, combined injection of 1.25 mg IVB and 2 mg IVT, and focal or modified grid MPC. To eliminate the possible effects of systemic confounders, we selected fellow eyes of bilaterally treated subjects who had undergone different treatments; eventually 30 eyes of 15 patients were re-evaluated at baseline, 6, 12, 18, and 24 months. Using mixed model analysis, we compared the treatment protocols regarding visual acuity (VA) and central macular thickness (CMT). RESULTS: Improvement in VA in the IVB group was significantly greater compared to MPC at months 6 and 12 (P = 0.037 and P = 0.035, respectively) but this difference did not persist thereafter up to 24 months. Other levels of VA were comparable at different follow-up intervals (all P > 0.05). The only significant difference in CMT was observed in favor of the IVB group as compared to IVB/IVT group at 24 months (P = 0.048). CONCLUSION: Overall VA was superior in IVB group as compared to MPC up to 12 months. Although the IVB group showed superiority regarding CMT reduction over 24 months as compared to IVB/IVT group, it was comparable to the MPC group through the same period of follow up.

11.
Ophthalmic Surg Lasers Imaging Retina ; 44(6 Suppl): S36-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24220882

RESUMEN

The authors describe indocyanine green angiography (ICGA) and enhanced depth imaging optical coherence tomography (EDI-OCT) in a 46-year-old male patient with acute macular neuroretinopathy (AMN). The chief complaint was decreasing visual acuity and metamorphopsia in both eyes of 1-month duration. Visual field assessment, fluorescein angiography, OCT, ICGA, and EDI-OCT were performed initially and at 3 months. ICGA showed choroidal vascular hyperpermeability and punctuate choroidal hyperfluorescent spots, especially in the left eye. EDI-OCT showed increased choroidal macular thickness, with inner and outer retinal layers affected. EDI-OCT and ICGA reveal that both the choroid and retina can be affected in AMN; however, the primary pathology and localization of depth of involvement in AMN remains unclear.


Asunto(s)
Mácula Lútea , Enfermedades de la Retina/diagnóstico , Enfermedad Aguda , Colorantes , Angiografía con Fluoresceína/métodos , Humanos , Verde de Indocianina , Masculino , Persona de Mediana Edad , Tomografía de Coherencia Óptica/métodos
12.
Ophthalmic Surg Lasers Imaging Retina ; 44 Online: E17-9, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24256710

RESUMEN

A 65-year-old man presented with decreased visual acuity in his left eye of 10 days' duration. Ocular examination revealed visual acuity of 20/200 in the left eye caused by a visible retinal nematode (roundworm) located close to the fovea. Spectral-domain optical coherence tomography imaging showed the nematode in the retinal nerve fiber layer. The patient was followed up without treatment, and the nematode disappeared spontaneously after 5 weeks. Visual acuity in the affected eye improved to 20/25.


Asunto(s)
Infecciones Parasitarias del Ojo/diagnóstico , Nematodos/aislamiento & purificación , Infecciones por Nematodos/diagnóstico , Enfermedades de la Retina/diagnóstico , Tomografía de Coherencia Óptica , Anciano , Animales , Infecciones Parasitarias del Ojo/fisiopatología , Angiografía con Fluoresceína , Humanos , Masculino , Infecciones por Nematodos/fisiopatología , Fibras Nerviosas/parasitología , Fibras Nerviosas/patología , Enfermedades de la Retina/fisiopatología , Células Ganglionares de la Retina/parasitología , Células Ganglionares de la Retina/patología , Agudeza Visual
13.
Ophthalmic Surg Lasers Imaging Retina ; 44 Online: E17-9, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24548761

RESUMEN

A 65-year-old man presented with decreased visual acuity in his left eye of 10 days' duration. Ocular examination revealed visual acuity of 20/200 in the left eye caused by a visible retinal nematode (roundworm) located close to the fovea. Spectral-domain optical coherence tomography imaging showed the nematode in the retinal nerve fiber layer. The patient was followed up without treatment, and the nematode disappeared spontaneously after 5 weeks. Visual acuity in the affected eye improved to 20/25.


Asunto(s)
Infecciones Parasitarias del Ojo/diagnóstico , Nematodos/aislamiento & purificación , Infecciones por Nematodos/diagnóstico , Retina/parasitología , Enfermedades de la Retina/diagnóstico , Tomografía de Coherencia Óptica/métodos , Anciano , Animales , Angiografía con Fluoresceína , Fondo de Ojo , Humanos , Masculino , Retina/patología , Enfermedades de la Retina/parasitología
14.
J Cataract Refract Surg ; 38(6): 1094-6, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22624910

RESUMEN

A 25-year-old woman with myopia who had an AC pIOL implantation in the left eye and posterior chamber pIOL implantation in the right eye developed bilateral granulomatous panuveitis 2 months after the second surgery. Physical examination showed bilateral Koeppe and Busacca nodules. Fluorescein angiography showed diffuse vascular and retinal pigment epithelial leakage in both eyes. With assessment of sympathetic ophthalmia, treatment with a high-dose systemic steroid was started. Oral cyclosporine and azathioprine were later added. Because the uveitis was not controlled, adalimumab was added. After 6 doses of adalimumab (40 mg subcutaneously), the uveitis subsided and corticosteroid and other immunosuppressive agents were tapered. Refractive AC pIOL implantation should be added to the list of intraocular procedures that may induce sympathetic ophthalmia. Adalimumab may have a therapeutic role in its management.


Asunto(s)
Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Implantación de Lentes Intraoculares/efectos adversos , Miopía Degenerativa/cirugía , Oftalmía Simpática/tratamiento farmacológico , Lentes Intraoculares Fáquicas , Adalimumab , Adulto , Femenino , Angiografía con Fluoresceína , Humanos , Oftalmía Simpática/diagnóstico , Oftalmía Simpática/etiología , Agudeza Visual
15.
Ophthalmic Surg Lasers Imaging ; 43(1): 57-62, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22251846

RESUMEN

BACKGROUND AND OBJECTIVE: To evaluate a minimally invasive injector for intravitreal and subconjunctival administration of medications. MATERIALS AND METHODS: The device has a microneedle that communicates with an internal formulation chamber. A piercing depth-limiting flange restricts microneedle penetration to a depth of less than 1 mm and defines the location of the pars plana from the limbus. The jet injector creates a force of up to 1,000 psi, forcing the medication through the remaining sclera/choroid thickness. The device was tested in 28 enucleated rabbit eyes and 9 experimental and 4 control rabbit eyes to define jet pressure for subconjunctival and intravitreal injection. RESULTS: Injection pressures of 76 to 156 psi were needed for subconjunctival injection and 974 psi for intravitreal injection. Clinical and histologic examinations did not reveal damage to intraocular structures. CONCLUSION: The semi-automated jet injector facilitated intravitreal/subconjunctival injection. The microneedle-assisted jet injector minimized the risk of wet injection by anchoring the microneedle in the sclera.


Asunto(s)
Sistemas de Liberación de Medicamentos/instrumentación , Inyecciones Intravítreas/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Soluciones Oftálmicas/administración & dosificación , Preparaciones Farmacéuticas/administración & dosificación , Animales , Conjuntiva/efectos de los fármacos , Inyecciones a Chorro/instrumentación , Conejos , Cuerpo Vítreo/efectos de los fármacos
16.
Retina ; 32(2): 314-21, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22234244

RESUMEN

PURPOSE: The purpose of this study was to report the 24-month findings of a randomized clinical trial comparing intravitreal bevacizumab (IVB) injection alone or in combination with intravitreal triamcinolone acetonide (IVT) versus macular laser photocoagulation (MPC) as a primary treatment for diabetic macular edema. METHODS: The eyes were randomly assigned to 1 of the 3 study arms: the IVB group, patients who received 1.25 mg IVB; the IVB/IVT group, patients who received 1.25 mg of IVB and 2 mg of IVT; and the MPC group, patients who underwent focal or modified grid laser. Of 150 eyes (50 in each group) in the primary trial, 123, 119, and 113 eyes completed follow-ups at 12, 18, and 24 months, respectively. A total of 39 (78%), 36 (72%), and 38 (76%) eyes in the IVB, IVB/IVT, and MPC groups remained in the study within 24 months, respectively. Retreatment was performed at 3-month intervals whenever indicated. Data from a 24-month follow-up are presented. Changes in best-corrected visual acuity and central macular thickness up to 24 months were the main outcome measures in this study. RESULTS: Retreatment was required in 37 (94.9%), 27 (75.0%), and 31 (81.6%) eyes, respectively, in the IVB, IVB/IVT, and MPC groups up to 24 months. The significant superiority of visual acuity improvement in the IVB group, which had been noted at Month 6, did not sustain thereafter up to 24 months, and the difference among the groups was not significant at all visits. However, the mean visual acuity improvement was greater in the IVB group than the other groups and in the IVB/IVT group compared with the MPC group. The reduction of central macular thickness was more in the IVB group in relation to the other two treatment groups; however, the difference among the groups was not statistically significant at any of the follow-up visits. CONCLUSION: In terms of vision improvement, the significant superiority of the IVB over the combined IVB/IVT and MPC treatment that had been observed at Month 6 did not sustain up to 24 months. This means that although IVB treatment may be a better choice than two other options in short term, the magnitude of this beneficial effect diminishes over time.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Retinopatía Diabética/terapia , Glucocorticoides/uso terapéutico , Coagulación con Láser , Edema Macular/terapia , Triamcinolona Acetonida/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Anticuerpos Monoclonales Humanizados/administración & dosificación , Bevacizumab , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/cirugía , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Inyecciones Intravítreas , Edema Macular/tratamiento farmacológico , Edema Macular/fisiopatología , Edema Macular/cirugía , Masculino , Persona de Mediana Edad , Retratamiento , Factores de Tiempo , Resultado del Tratamiento , Triamcinolona Acetonida/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Agudeza Visual/fisiología
17.
Ophthalmic Surg Lasers Imaging ; 43(2): 143-51, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22230169

RESUMEN

BACKGROUND AND OBJECTIVE: Traditional ultrasound imaging systems for ophthalmology employ slow, mechanical scanning of a single-element ultrasound transducer. The goal was to demonstrate rapid examination of the anterior and posterior segment with a three-dimensional (3D) commercial ultrasound system incorporating high-resolution linear probe arrays. MATERIALS AND METHODS: The 3D images of the porcine eye were generated in approximately 10 seconds by scanning one of two commercial linear arrays (25- and 50-MHz). Healthy enucleated pig eyes were compared with those with induced injury or placement of a foreign material (eg, metal). Rapid, volumetric imaging was also demonstrated in one human eye in vivo. RESULTS: The 50-MHz probe provided exquisite volumetric images of the anterior segment at a depth up to 15 mm and axial resolution of 30 µm. The 25-MHz probe provided a larger field of view (lateral X depth: 20 × 30 mm), sufficient for capturing the entire anterior and posterior segments of the pig eye, at a resolution of 60 µm. A 50-MHz scan through the human eyelid illustrated detailed structures of the Meibomian glands, cilia, cornea, and anterior segment back to the posterior capsule. CONCLUSION: The 3D system with its high-frequency ultrasound arrays, fast data acquisition, and volume rendering capability shows promise for investigating anterior and posterior structures of the eye.


Asunto(s)
Segmento Anterior del Ojo/diagnóstico por imagen , Técnicas de Diagnóstico Oftalmológico/instrumentación , Segmento Posterior del Ojo/diagnóstico por imagen , Animales , Lesiones Oculares/diagnóstico por imagen , Porcinos , Transductores , Ultrasonografía
18.
J Refract Surg ; 28(1): 59-64, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21913630

RESUMEN

PURPOSE: To investigate the effect of blunt foreign body impact on a human cornea after photorefractive keratectomy (PRK) and LASIK using a simulation model. METHODS: Computational simulations were performed using a finite element analysis program (LS-Dyna, Livermore Software Technology Corp). The blunt foreign body was set to impact at the center of the corneal surface models (after PRK and LASIK) with thicknesses of 500, 450, 400, 350, and 300 µm. Corneal rupture was assumed to occur at a peak stress of 9.45 MPa and at a strain of 18%. The foreign body projectile was blunt in shape, made from aluminum, contained plastic-kinematic properties, and had a density of 2700 kg/m(3). RESULTS: The projectile was launched at the center of the cornea with velocities ranging from 20 to 60 m/s. The threshold of impact velocities creating rupture in corneal thicknesses of 500, 450, 400, 350, and 300 µm were 33, 32.8, 30.7, 27.9, and 22.8 m/s, respectively, in the PRK model. In the LASIK model, the thresholds creating rupture in the stromal bed of the corneas with thicknesses of 500, 450, 400, 350, and 300 µm were 40, 38.1, 35.6, 31.5, and 26.7 m/s, respectively. The 110-µm corneal flap in the LASIK model ruptured at all velocities. CONCLUSIONS: Ruptures occurred at lower velocities in the PRK cornea model than in the corneal stromal bed of the LASIK model following blunt foreign body impact.


Asunto(s)
Lesiones de la Cornea , Lesiones Oculares/etiología , Análisis de Elementos Finitos , Queratomileusis por Láser In Situ , Queratectomía Fotorrefractiva , Dehiscencia de la Herida Operatoria/etiología , Heridas no Penetrantes/etiología , Simulación por Computador , Córnea/cirugía , Humanos , Láseres de Excímeros/uso terapéutico , Rotura , Colgajos Quirúrgicos
19.
Ophthalmic Surg Lasers Imaging ; 42 Online: e135-8, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22165950

RESUMEN

The authors report spectral-domain optical coherence tomography findings of laser pointer-induced maculopathy in a 25-year-old man after accidental laser pointer exposure of less than 1 second. The Class 3R laser pointer (output wavelength 532 nm and output power 3.5 to 4.5 mW [continuous wave]) had U.S. Food and Drug Administration certification. One day after exposure, he had visual blurring and metamorphopsia of his right eye. He was treated with a systemic high-dose corticosteroid. Spectral-domain optical coherence tomography disclosed a hyperreflective band in the foveal region. After 1 week of treatment, disappearance of hyperreflectivity was observed on spectral-domain optical coherence tomography. At 6 months, residual disruption of the outer retinal layer at the fovea remained unchanged. Spectral-domain optical coherence tomography was a useful and sensitive tool for evaluating retinal damage and subsequent resolution after treatment.


Asunto(s)
Corticoesteroides/uso terapéutico , Lesiones Oculares/tratamiento farmacológico , Rayos Láser/efectos adversos , Prednisolona/uso terapéutico , Enfermedades de la Retina/tratamiento farmacológico , Adulto , Humanos , Masculino , Enfermedades de la Retina/diagnóstico , Tomografía de Coherencia Óptica , Resultado del Tratamiento
20.
Ophthalmic Surg Lasers Imaging ; 42(5): 394-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21899244

RESUMEN

BACKGROUND AND OBJECTIVE: Changes in corneal endothelial cell (CEC) indices 24 months after Ahmed valve (New World Medical, Inc., Rancho Cucamonga, CA) and single-plate Molteno implants (Molteno Ophthalmic Limited, Dunedin, New Zealand) were evaluated. PATIENTS AND METHODS: This cohort included Ahmed valve (29 eyes) or single-plate Molteno (28 eyes) implants. Preoperative and postoperative central CEC indices were compared. Main outcome measure was endothelial cell count. RESULTS: Twenty-four months postoperatively, no difference in visual acuity improvement or decrease in antiglaucoma medications was observed between groups. The Molteno group showed better postoperative intraocular pressure control (P < .001). An 11.52% (Ahmed) and 12.37% (Molteno) reduction in CEC density (cells/mm(2)) and 3.78 (Ahmed) and 2.48 (Molteno) increase in CEC area (mm(2)) was observed, but no significant between-group difference in CEC density and area or corneal thickness. CONCLUSION: Twenty-four months after Ahmed valve or Molteno implant, statistically significant quantitative (cell density) and minor qualitative (cell area) changes in central CEC were observed. Both groups appeared to have similar CEC damage.


Asunto(s)
Endotelio Corneal/patología , Implantes de Drenaje de Glaucoma , Glaucoma/cirugía , Anciano , Recuento de Células , Estudios de Cohortes , Femenino , Glaucoma/fisiopatología , Humanos , Presión Intraocular/fisiología , Irán , Masculino , Persona de Mediana Edad , Implantes de Molteno , Evaluación de Resultado en la Atención de Salud , Implantación de Prótesis , Agudeza Visual/fisiología
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