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1.
Ophthalmology ; 129(7): 781-791, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35202616

RESUMO

PURPOSE: To develop and validate a deep learning (DL) system for predicting each point on visual fields (VFs) from disc and OCT imaging and derive a structure-function mapping. DESIGN: Retrospective, cross-sectional database study. PARTICIPANTS: A total of 6437 patients undergoing routine care for glaucoma in 3 clinical sites in the United Kingdom. METHODS: OCT and infrared reflectance (IR) optic disc imaging were paired with the closest VF within 7 days. EfficientNet B2 was used to train 2 single-modality DL models to predict each of the 52 sensitivity points on the 24-2 VF pattern. A policy DL model was designed and trained to fuse the 2 model predictions. MAIN OUTCOME MEASURES: Pointwise mean absolute error (PMAE). RESULTS: A total of 5078 imaging scans to VF pairs were used as a held-out test set to measure the final performance. The improvement in PMAE with the policy model was 0.485 (0.438, 0.533) decibels (dB) compared with the IR image of the disc alone and 0.060 (0.047, 0.073) dB with to the OCT alone. The improvement with the policy fusion model was statistically significant (P < 0.0001). Occlusion masking shows that the DL models learned the correct structure-function mapping in a data-driven, feature agnostic fashion. CONCLUSIONS: The multimodal, policy DL model performed the best; it provided explainable maps of its confidence in fusing data from single modalities and provides a pathway for probing the structure-function relationship in glaucoma.


Assuntos
Aprendizado Profundo , Glaucoma , Disco Óptico , Doenças do Nervo Óptico , Glaucoma/diagnóstico , Humanos , Pressão Intraocular , Disco Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico , Políticas , Estudos Retrospectivos , Tomografia de Coerência Óptica , Testes de Campo Visual/métodos , Campos Visuais
2.
J Glaucoma ; 30(6): 473-480, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33813559

RESUMO

PRCIS: No significant difference was found between the intraocular pressure (IOP) lowering of omidenepag isopropyl 0.002% once daily (QD) and twice daily (BID). However, adverse events (AEs) were higher in the BID arm; thus, QD dosing is the preferred dosing frequency for further investigation. PURPOSE: This phase 2, randomized, double-masked, parallel-arm, multicenter study (NCT03858894) was conducted in the United States to examine whether the efficacy and safety of omidenepag isopropyl 0.002% BID dosing was superior to QD dosing in subjects with primary open-angle glaucoma or ocular hypertension. METHODS: Randomized subjects (1:1) received omidenepag isopropyl 0.002% QD (n=50) or BID (n=48) for 6 weeks (after a ≤4-week washout period). IOP was measured at 8:00 am, 12:00 pm, and 4:00 pm at baseline and weeks 2 and 6. The primary efficacy endpoint was IOP at each timepoint at weeks 2 and 6. AEs were evaluated. RESULTS: Baseline mean diurnal IOP (±SD) post washout was 25.4±2.9 mm Hg (BID) and 24.6±1.9 mm Hg (QD). At weeks 2 and 6, clinically significant IOP reductions from baseline were observed for omidenepag isopropyl BID and QD treatments. Least-squares mean (±SE) IOP differences (BID versus QD) were not statistically significant (week 2: 0.44±0.68 to 1.08±0.65 mm Hg; week 6: 0.36±0.63 to 0.68±0.68 mm Hg) at any timepoint (all P > 0.05). AEs were 3-fold greater in the BID arm (41.7%; QD: 14.0%); the most frequently reported AE was conjunctival/ocular hyperemia (BID: 22.9%; QD: 2.0%). Five subjects discontinued omidenepag isopropyl prematurely, 4 of 5 owing to AEs (BID: 4; QD: 0). CONCLUSION: In this study, the benefit-risk profile of omidenepag isopropyl 0.002% QD was more favorable than the benefit-risk profile of BID. This difference was driven by a higher incidence of local tolerability issues in the BID arm.


Assuntos
Glaucoma de Ângulo Aberto , Hipertensão Ocular , Anti-Hipertensivos/efeitos adversos , Método Duplo-Cego , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glicina/efeitos adversos , Glicina/análogos & derivados , Humanos , Pressão Intraocular , Hipertensão Ocular/tratamento farmacológico , Soluções Oftálmicas , Pirazóis/efeitos adversos , Piridinas/efeitos adversos , Resultado do Tratamento
3.
Cephalalgia ; 35(5): 379-88, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25106663

RESUMO

BACKGROUND: This study explored whether antagonism of orexin receptors might be an effective mechanism for migraine prevention. METHODS: We conducted a randomized, double-blind, placebo-controlled, pilot trial. Patients experiencing four to 14 days with migraine during a one-month baseline period were randomized to the orexin receptor antagonist filorexant 10 mg nightly or placebo for three months. Efficacy was assessed by mean monthly migraine days (headache plus at least one associated migraine symptom) and headache days. Safety and tolerability were assessed by adverse event reports and laboratory tests. RESULTS: Of 120 patients treated with filorexant and 115 treated with placebo, 97 (81%) and 101 (88%), respectively, completed the trial. There was no statistically significant difference between treatments for change from baseline in mean monthly migraine days (filorexant = -1.7, placebo = -1.3, difference = -0.4 (95% CI: -1.3, 0.4)) or headache days (filorexant = -1.7, placebo = -1.2, difference = -0.5 (95% CI: -1.4, 0.4)). Filorexant was generally well tolerated but was associated with a higher proportion of patients who reported adverse events than placebo (47% vs 37%), particularly somnolence (13% vs 4%). CONCLUSIONS: These data fail to provide evidence that antagonism of orexin receptors with filorexant, when administered at night, is effective for migraine prophylaxis.


Assuntos
Transtornos de Enxaqueca/prevenção & controle , Antagonistas dos Receptores de Orexina/uso terapêutico , Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino
4.
Am J Ophthalmol ; 153(6): 1187-96, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22310086

RESUMO

PURPOSE: To compare the efficacy and safety of tafluprost, a preservative-free (PF) prostaglandin analogue, with PF timolol in patients with open-angle glaucoma or ocular hypertension. DESIGN: Randomized, double-masked, multicenter clinical trial. METHODS: After discontinuation and washout of existing ocular hypotensive treatment, patients who had intraocular pressure (IOP) ≥23 and ≤36 mm Hg in at least 1 eye at the 08:00 hour time point were randomized 1:1 to 12 weeks of treatment with either PF tafluprost 0.0015% or PF timolol 0.5%. IOP was measured 3 times during the day (08:00, 10:00, 16:00 hours) at baseline and at weeks 2, 6, and 12. It was hypothesized that PF tafluprost would be noninferior to PF timolol over 12 weeks with regard to change from baseline IOP. The trial was powered for a noninferiority margin of 1.5 mm Hg at each of the 9 time points assessed. RESULTS: A total of 643 patients were randomized and 618 completed (PF tafluprost = 306, PF timolol = 312). IOPs at the 3 time points assessed during the baseline visit ranged from 23.8 to 26.1 mm Hg in the PF tafluprost group and 23.5 to 26.0 mm Hg in the PF timolol group. IOPs at the 3 time points assessed during the 12-week visit ranged from 17.4 to 18.6 mm Hg for PF tafluprost and 17.9 to 18.5 mm Hg for PF timolol. At all 9 time points, the upper limits of the 2-sided 95% confidence intervals for the difference between treatments in IOP lowering were less than the prespecified noninferiority margin. Similar percentages of PF tafluprost and PF timolol patients reported ocular pain/stinging/irritation (4.4% vs 4.6%) and pruritus (2.5% vs 1.5%). The percentages of PF tafluprost and PF timolol patients reporting conjunctival hyperemia were 4.4% vs 1.2% (nominal P = .016). CONCLUSIONS: The IOP-lowering effect of PF tafluprost was noninferior to that of PF timolol. PF tafluprost is an efficacious and generally well-tolerated ocular hypotensive agent.


Assuntos
Anti-Hipertensivos/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Pressão Intraocular/efeitos dos fármacos , Prostaglandinas F/uso terapêutico , Timolol/uso terapêutico , Anti-Hipertensivos/efeitos adversos , Método Duplo-Cego , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/tratamento farmacológico , Hipertensão Ocular/fisiopatologia , Soluções Oftálmicas , Conservantes Farmacêuticos , Prostaglandinas F/efeitos adversos , Timolol/efeitos adversos , Tonometria Ocular , Resultado do Tratamento , Acuidade Visual/fisiologia
5.
Cornea ; 28(2): 231-2, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19158574

RESUMO

PURPOSES: The purposes of this study were to report the presentation and management of an acquired total anterior staphyloma that resulted from a fungal corneal ulcer and to discuss its pathogenesis. METHODS: Observational case report. Clinical observation and surgical intervention of a patient who developed a total anterior staphyloma after a partially treated fungal corneal ulcer. RESULTS: The patient presented with a large traumatic fungal ulcer but was poorly compliant with follow-up and medications. He subsequently presented with a large total anterior staphyloma that resulted from perforation of the ulcer with plugging of the defect with iris and formation of a pseudocornea over the iris. The anterior staphyloma measured 15 x 16 mm and progressed to a stage where the patient was unable to close his eyelids and required a sclerokeratoplasty. Currently, vision is poor from amblyopia and a cloudy graft; however, the eye is intact and comfortable. CONCLUSIONS: Anterior staphylomas usually result from untreated fungal ulcers in developing nations. Poor compliance with medications and follow-up was the cause of our patient's anterior staphyloma. Sclerokeratoplasty can restore the globe structurally but has poor visual prognosis.


Assuntos
Doenças da Córnea/etiologia , Úlcera da Córnea/complicações , Úlcera da Córnea/microbiologia , Micoses/complicações , Ambliopia/complicações , Antifúngicos/uso terapêutico , Doenças da Córnea/patologia , Doenças da Córnea/cirurgia , Transplante de Córnea , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Cooperação do Paciente , Esclera/cirurgia , Baixa Visão/etiologia
6.
J Refract Surg ; 20(5): 454-64, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15523957

RESUMO

PURPOSE: To measure the largest diameter of the anterior chamber (AC) and posterior chamber (PC) dimension and its orientation and determine the relationship with the principal keratometric meridians. METHODS: Twenty-eight eyes of 14 subjects were scanned with high frequency (50 MHz) ultrasound in sequential meridional scan planes at 30 degrees increments. Observer identified angle and ciliary sulcus recess boundaries in each patient scan set were fit with an elliptical model to obtain the ellipse semi-major axis corresponding to the largest diameter and its meridional orientation. Anterior and posterior chamber diameters from raw data and model fit were compared using linear statistics. Circular statistics were used to compare the orientation of the largest diameter for raw ultrasound measurements, model estimations of largest diameter, and autorefractor determined keratometric axes. RESULTS: The mean model diameters were anterior chamber OD 12.07 mm (0.32 SD); anterior chamber OS 12.06 mm (0.36 SD); posterior chamber OD 12.35 mm (0.42 SD); posterior chamber OS 12.33 mm (0.43 SD). The general trend for orientation of the meridian of largest diameter was in the horizontal meridian. In over 35% of eyes the difference between AC or PC meridian and the flat keratometric axis was greater than 20 degrees. CONCLUSIONS: Accurate and reproducible anterior segment biometry depends on visualization of structures and minimization of eye and head movement error. The range and standard deviation of the diameter and orientation measures suggests anatomic variation is sufficient to require biometry for proper sizing and placement of intraocular devices that use angle or sulcus fixation.


Assuntos
Câmara Anterior/diagnóstico por imagem , Biometria/métodos , Adulto , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Valores de Referência , Refração Ocular , Reprodutibilidade dos Testes , Ultrassonografia
7.
Ophthalmology ; 111(7): 1344-51, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15234135

RESUMO

PURPOSE: Conventional ophthalmic ultrasonography is performed using 10-megahertz (MHz) transducers. Our aim was to explore the use of higher frequency ultrasound to provide improved resolution of the posterior pole. DESIGN: Prospective case series. PARTICIPANTS: One normal subject and 5 subjects with pathologies affecting the posterior coats, including nevii, small melanomas, and macular hole. METHODS: We modeled the frequency-dependent attenuation of ultrasound across the eye to develop an understanding of the range of frequencies that might be practically applied for imaging of the posterior pole. We compared images of the posterior coats made at 10, 15, and 20 MHz, and 20-MHz ultrasound images of pathologies with 10-MHz ultrasound and optical coherence tomography (OCT). MAIN OUTCOME MEASURES: Ability to resolve normal and pathologic structures affecting posterior coats of the eye. RESULTS: Modeling showed that frequencies of 20 to 25 MHz might be used for posterior pole imaging. Twenty-megahertz images allowed differentiation of the retina, choroid, and sclera. In addition, at 20 MHz the retina showed banding patterns suggesting an internal structure comparable in many respects to that seen in OCT and histology. Images of ocular pathology provided much improved detail relative to 10-MHz images and deeper penetration than OCT. CONCLUSIONS: Twenty-megahertz ultrasound can be practically employed for imaging of the posterior pole of the eye, providing a 2-fold improvement in resolution relative to conventional 10-MHz instruments. Although not providing the resolution of OCT, ultrasound can be used in the presence of optical opacities and allows evaluation of deeper tissue structures.


Assuntos
Melanoma/diagnóstico por imagem , Nevo Pigmentado/diagnóstico por imagem , Perfurações Retinianas/diagnóstico por imagem , Neoplasias Uveais/diagnóstico por imagem , Adulto , Corioide/diagnóstico por imagem , Feminino , Humanos , Estudos Prospectivos , Retina/diagnóstico por imagem , Esclera/diagnóstico por imagem , Tomografia de Coerência Óptica , Ultrassonografia
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