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1.
Ophthalmol Sci ; 4(5): 100470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827487

RESUMO

Purpose: Automated machine learning (AutoML) has emerged as a novel tool for medical professionals lacking coding experience, enabling them to develop predictive models for treatment outcomes. This study evaluated the performance of AutoML tools in developing models predicting the success of pneumatic retinopexy (PR) in treatment of rhegmatogenous retinal detachment (RRD). These models were then compared with custom models created by machine learning (ML) experts. Design: Retrospective multicenter study. Participants: Five hundred and thirty nine consecutive patients with primary RRD that underwent PR by a vitreoretinal fellow at 6 training hospitals between 2002 and 2022. Methods: We used 2 AutoML platforms: MATLAB Classification Learner and Google Cloud AutoML. Additional models were developed by computer scientists. We included patient demographics and baseline characteristics, including lens and macula status, RRD size, number and location of breaks, presence of vitreous hemorrhage and lattice degeneration, and physicians' experience. The dataset was split into a training (n = 483) and test set (n = 56). The training set, with a 2:1 success-to-failure ratio, was used to train the MATLAB models. Because Google Cloud AutoML requires a minimum of 1000 samples, the training set was tripled to create a new set with 1449 datapoints. Additionally, balanced datasets with a 1:1 success-to-failure ratio were created using Python. Main Outcome Measures: Single-procedure anatomic success rate, as predicted by the ML models. F2 scores and area under the receiver operating curve (AUROC) were used as primary metrics to compare models. Results: The best performing AutoML model (F2 score: 0.85; AUROC: 0.90; MATLAB), showed comparable performance to the custom model (0.92, 0.86) when trained on the balanced datasets. However, training the AutoML model with imbalanced data yielded misleadingly high AUROC (0.81) despite low F2-score (0.2) and sensitivity (0.17). Conclusions: We demonstrated the feasibility of using AutoML as an accessible tool for medical professionals to develop models from clinical data. Such models can ultimately aid in the clinical decision-making, contributing to better patient outcomes. However, outcomes can be misleading or unreliable if used naively. Limitations exist, particularly if datasets contain missing variables or are highly imbalanced. Proper model selection and data preprocessing can improve the reliability of AutoML tools. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

2.
Nature ; 630(8015): 70-76, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811730

RESUMO

Colour centres in diamond have emerged as a leading solid-state platform for advancing quantum technologies, satisfying the DiVincenzo criteria1 and recently achieving quantum advantage in secret key distribution2. Blueprint studies3-5 indicate that general-purpose quantum computing using local quantum communication networks will require millions of physical qubits to encode thousands of logical qubits, presenting an open scalability challenge. Here we introduce a modular quantum system-on-chip (QSoC) architecture that integrates thousands of individually addressable tin-vacancy spin qubits in two-dimensional arrays of quantum microchiplets into an application-specific integrated circuit designed for cryogenic control. We demonstrate crucial fabrication steps and architectural subcomponents, including QSoC transfer by means of a 'lock-and-release' method for large-scale heterogeneous integration, high-throughput spin-qubit calibration and spectral tuning, and efficient spin state preparation and measurement. This QSoC architecture supports full connectivity for quantum memory arrays by spectral tuning across spin-photon frequency channels. Design studies building on these measurements indicate further scaling potential by means of increased qubit density, larger QSoC active regions and optical networking across QSoC modules.

3.
Plast Reconstr Surg Glob Open ; 11(9): e5281, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37753332

RESUMO

Background: Plastic surgery and social media have become inextricably linked through patient procurement, practice growth, and academic exposure. Other surgical fields have demonstrated that tweeting is positively correlated with increased citations. This study aimed to elucidate the effect of Twitter on traditional bibliometrics in plastic surgery and parse out the kinds of tweets that are most correlated with citations. Methods: Articles from May to October of 2018 from Plastic and Reconstructive Surgery and Aesthetic Surgery Journal were analyzed to determine the citation count, number and backgrounds of Twitter users tweeting about the article, and total tweets. Multiple linear regression was performed to correlate these variables to citation count. Results: A total of 369 articles were analyzed. Plastic and Reconstructive Surgery had significantly more average tweets per article compared to Aesthetic Surgery Journal (21.8 versus 10.2, P < 0.001), Additionally, a number of tweets (r = 0.45, P < 0.001) and reaching more total followers (r = 0.48, P < 0.001) were both positively correlated with citations. Multiple linear regression demonstrated that tweets from self-identified scientists were positively correlated with citations (r = 0.99, P = 0.001). Tweets from science communicators had no correlation with citations (r = -0.012, P = 0.726). Tweets coming domestically from the country of the author were also associated with more citations (r = 0.164, P = 0.013). Conclusions: Twitter activity, including the number of followers reached, for an article is positively correlated with citations. Interestingly, the kind of person tweeting affected the citations as well. Domestic tweets and those from scientists were associated with more citations. This implies that Twitter can be an effective form of academic dissemination, provided the "right" Twitter users are promoting the article.

4.
Nano Lett ; 23(17): 7852-7858, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37643457

RESUMO

A central goal in many quantum information processing applications is a network of quantum memories that can be entangled with each other while being individually controlled and measured with high fidelity. This goal has motivated the development of programmable photonic integrated circuits (PICs) with integrated spin quantum memories using diamond color center spin-photon interfaces. However, this approach introduces a challenge into the microwave control of individual spins within closely packed registers. Here, we present a quantum memory-integrated photonics platform capable of (i) the integration of multiple diamond color center spins into a cryogenically compatible, high-speed programmable PIC platform, (ii) selective manipulation of individual spin qubits addressed via tunable magnetic field gradients, and (iii) simultaneous control of qubits using numerically optimized microwave pulse shaping. The combination of localized optical control, enabled by the PIC platform, together with selective spin manipulation opens the path to scalable quantum networks on intrachip and interchip platforms.

5.
Nat Mater ; 22(11): 1338-1344, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37604910

RESUMO

Solid-state quantum emitters have emerged as a leading quantum memory for quantum networking applications. However, standard optical characterization techniques are neither efficient nor repeatable at scale. Here we introduce and demonstrate spectroscopic techniques that enable large-scale, automated characterization of colour centres. We first demonstrate the ability to track colour centres by registering them to a fabricated machine-readable global coordinate system, enabling a systematic comparison of the same colour centre sites over many experiments. We then implement resonant photoluminescence excitation in a widefield cryogenic microscope to parallelize resonant spectroscopy, achieving two orders of magnitude speed-up over confocal microscopy. Finally, we demonstrate automated chip-scale characterization of colour centres and devices at room temperature, imaging thousands of microscope fields of view. These tools will enable the accelerated identification of useful quantum emitters at chip scale, enabling advances in scaling up colour centre platforms for quantum information applications, materials science and device design and characterization.

6.
Phys Rev Lett ; 129(17): 173603, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332262

RESUMO

Tin-vacancy centers in diamond are promising spin-photon interfaces owing to their high quantum efficiency, large Debye-Waller factor, and compatibility with photonic nanostructuring. Benchmarking their single-photon indistinguishability is a key challenge for future applications. Here, we report the generation of single photons with 99.7_{-2.5}^{+0.3}% purity and 63(9)% indistinguishability from a resonantly excited tin-vacancy center in a single-mode waveguide. We obtain quantum control of the optical transition with 1.71(1)-ns-long π pulses of 77.1(8)% fidelity and show it is spectrally stable over 100 ms. A modest Purcell enhancement factor of 12 would enhance the indistinguishability to 95%.

7.
Phys Rev Lett ; 127(14): 147402, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34652204

RESUMO

Quantum emitters in diamond are leading optically accessible solid-state qubits. Among these, Group IV-vacancy defect centers have attracted great interest as coherent and stable optical interfaces to long-lived spin states. Theory indicates that their inversion symmetry provides first-order insensitivity to stray electric fields, a common limitation for optical coherence in any host material. Here we experimentally quantify this electric field dependence via an external electric field applied to individual tin-vacancy (SnV) centers in diamond. These measurements reveal that the permanent electric dipole moment and polarizability are at least 4 orders of magnitude smaller than for the diamond nitrogen vacancy (NV) centers, representing the first direct measurement of the inversion symmetry protection of a Group IV defect in diamond. Moreover, we show that by modulating the electric-field-induced dipole we can use the SnV as a nanoscale probe of local electric field noise, and we employ this technique to highlight the effect of spectral diffusion on the SnV.

8.
Front Immunol ; 12: 657945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912186

RESUMO

Human cytomegalovirus (HCMV) infection is not cleared by the initial immune response but persists for the lifetime of the host, in part due to its ability to establish a latent infection in cells of the myeloid lineage. HCMV has been shown to manipulate the secretion of cellular proteins during both lytic and latent infection; with changes caused by latent infection mainly investigated in CD34+ progenitor cells. Whilst CD34+ cells are generally bone marrow resident, their derivative CD14+ monocytes migrate to the periphery where they briefly circulate until extravasation into tissue sites. We have analyzed the effect of HCMV latent infection on the secretome of CD14+ monocytes, identifying an upregulation of both CCL8 and CXCL10 chemokines in the CD14+ latency-associated secretome. Unlike CD34+ cells, the CD14+ latency-associated secretome did not induce migration of resting immune cell subsets but did induce migration of activated NK and T cells expressing CXCR3 in a CXCL10 dependent manner. As reported in CD34+ latent infection, the CD14+ latency-associated secretome also suppressed the anti-viral activity of stimulated CD4+ T cells. Surprisingly, however, co-culture of activated autologous CD4+ T cells with latently infected monocytes resulted in reactivation of HCMV at levels comparable to those observed using M-CSF and IL-1ß cytokines. We propose that these events represent a potential strategy to enable HCMV reactivation and local dissemination of the virus at peripheral tissue sites.


Assuntos
Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Ativação Viral , Latência Viral , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Quimiotaxia de Leucócito/imunologia , Citocinas/metabolismo , Infecções por Citomegalovirus/metabolismo , Humanos , Ativação Linfocitária/imunologia , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/virologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Replicação Viral
9.
Ophthalmic Surg Lasers Imaging Retina ; 52(2): 84-92, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33626169

RESUMO

BACKGROUND AND OBJECTIVE: To identify factors associated with successful treatment discontinuation in eyes with retinal vein occlusions (RVOs) and macular edema (ME) in real-world settings. PATIENTS AND METHODS: Retrospective study of 214 eyes with RVO and ME with 24-month follow-up at five academic centers. Regression analyses identified factors associated with (1) successful treatment discontinuation for at least 6 months without fluid recurrence and (2) best-corrected visual acuity (BCVA) at 24 months. RESULTS: Forty percent of eyes with branch RVO and 35% with central RVO (CRVO) / hemi-retinal RVO (HRVO) successfully discontinued therapy without fluid recurrence, with median time to discontinuation of 6 and 7 months, respectively. Lower 6-month central subfield thickness was associated with greater likelihood of treatment discontinuation within 24 months for eyes with CRVO/HRVO (P = .001), whereas better 6-month BCVA was associated with better 24-month BCVA for all RVO subtypes (P < .001). CONCLUSION: Early anatomic response at 6 months is associated with greater likelihood of stopping treatments. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:84-92.].


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Inibidores da Angiogênese/uso terapêutico , Seguimentos , Humanos , Injeções Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Retina , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/diagnóstico , Oclusão da Veia Retiniana/tratamento farmacológico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual
10.
Nature ; 583(7815): 226-231, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641812

RESUMO

A central challenge in developing quantum computers and long-range quantum networks is the distribution of entanglement across many individually controllable qubits1. Colour centres in diamond have emerged as leading solid-state 'artificial atom' qubits2,3 because they enable on-demand remote entanglement4, coherent control of over ten ancillae qubits with minute-long coherence times5 and memory-enhanced quantum communication6. A critical next step is to integrate large numbers of artificial atoms with photonic architectures to enable large-scale quantum information processing systems. So far, these efforts have been stymied by qubit inhomogeneities, low device yield and complex device requirements. Here we introduce a process for the high-yield heterogeneous integration of 'quantum microchiplets'-diamond waveguide arrays containing highly coherent colour centres-on a photonic integrated circuit (PIC). We use this process to realize a 128-channel, defect-free array of germanium-vacancy and silicon-vacancy colour centres in an aluminium nitride PIC. Photoluminescence spectroscopy reveals long-term, stable and narrow average optical linewidths of 54 megahertz (146 megahertz) for germanium-vacancy (silicon-vacancy) emitters, close to the lifetime-limited linewidth of 32 megahertz (93 megahertz). We show that inhomogeneities of individual colour centre optical transitions can be compensated in situ by integrated tuning over 50 gigahertz without linewidth degradation. The ability to assemble large numbers of nearly indistinguishable and tunable artificial atoms into phase-stable PICs marks a key step towards multiplexed quantum repeaters7,8 and general-purpose quantum processors9-12.

11.
Phys Rev Lett ; 124(2): 023602, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004012

RESUMO

Solid-state quantum emitters that couple coherent optical transitions to long-lived spin qubits are essential for quantum networks. Here we report on the spin and optical properties of individual tin-vacancy (SnV) centers in diamond nanostructures. Through cryogenic magneto-optical and spin spectroscopy, we verify the inversion-symmetric electronic structure of the SnV, identify spin-conserving and spin-flipping transitions, characterize transition linewidths, measure electron spin lifetimes, and evaluate the spin dephasing time. We find that the optical transitions are consistent with the radiative lifetime limit even in nanofabricated structures. The spin lifetime is phonon limited with an exponential temperature scaling leading to T_{1}>10 ms, and the coherence time, T_{2}^{*} reaches the nuclear spin-bath limit upon cooling to 2.9 K. These spin properties exceed those of other inversion-symmetric color centers for which similar values require millikelvin temperatures. With a combination of coherent optical transitions and long spin coherence without dilution refrigeration, the SnV is a promising candidate for feasable and scalable quantum networking applications.

12.
Ophthalmol Retina ; 3(2): 140-145, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30931417

RESUMO

Objective: To evaluate the outcomes of patients undergoing pneumatic retinopexy (PR) performed by vitreoretinal fellows at 6 academic centers in the United States. Design: Retrospective, multicenter, consecutive case series. Participants: 483 patients with primary retinal detachments who underwent PR by 49 vitreoretinal fellows from 6 U.S. training sites between 2002 and 2016. Methods: We reviewed medical records of patients and recorded baseline clinical characteristics (age, sex, baseline visual acuity, lens status, presence of lattice degeneration, presence of vitreous hemorrhage, location of retinal breaks, macular status, and size of detachment), visual and anatomic outcomes at 3-months after PR, as well as training level and PR experience of the fellow at the time of the procedure. Main Outcome Measures: Single-procedure anatomic success and visual acuity at 3-months follow-up, and association with clinical and training-related factors. Results: Vitreoretinal fellows performed a variable number of PR, with a median of 7 cases per fellow (range 1-24). Single-procedure anatomic success was 66.8%, and mean LogMAR visual outcome was 0.43 (Snellen equivalent 20/54) at 3 months. Factors that were independently associated with single-procedure success include phakic lens status (P = 0.01), smaller size of retinal detachment (P = 0.02), and the fellow's procedure experience (P = 0.01). The only factor associated with worse visual outcome was baseline visual acuity (P < 0.001). Conclusion: Vitreoretinal fellows perform variably few pneumatic retinopexies but have outcomes comparable to reported rates by experienced specialists. Procedure experience of individual fellows may impact anatomic outcomes.


Assuntos
Procedimentos Cirúrgicos Oftalmológicos/métodos , Descolamento Retiniano/cirurgia , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos , Acuidade Visual
13.
J Neurophysiol ; 121(5): 1718-1734, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786219

RESUMO

Two macroscopic parameters describe the interstitial diffusion of substances in the extracellular space (ECS) of the brain, the ECS volume fraction α and the diffusion tortuosity λ. Past methods based on sampling the extracellular concentration of a membrane-impermeable ion tracer, such as tetramethylammonium (TMA+), can characterize either the dynamic α(t) alone or the constant α and λ in resting state but never the dynamic α(t) and λ(t) simultaneously in short-lived brain events. In this work, we propose to use a sinusoidal method of TMA+ to provide time-resolved quantification of α(t) and λ(t) in acute brain events. This method iontophoretically injects TMA+ in the brain ECS by a sinusoidal time pattern, samples the resulting TMA+ diffusion waveform at a distance, and analyzes the transient modulations of the amplitude and phase lag of the sampled TMA+ waveform to infer α(t) and λ(t). Applicability of the sinusoidal method was verified through computer simulations of the sinusoidal TMA+ diffusion waveform in cortical spreading depression. Parameter sensitivity analysis identified the sinusoidal frequency and the interelectrode distance as two key operating parameters. Compared with other TMA+-based methods, the sinusoidal method can more accurately capture the dynamic α(t) and λ(t) in acute brain events and is equally applicable to other pathological episodes such as epilepsy, transient ischemic attack, and brain injury. Future improvement of the method should focus on high-fidelity extraction of the waveform amplitude and phase angle. NEW & NOTEWORTHY An iontophoretic sinusoidal method of tetramethylammonium is described to capture the dynamic brain extracellular space volume fraction α and diffusion tortuosity λ. The sinusoidal frequency and interelectrode distance are two key operating parameters affecting the method's accuracy in capturing α(t) and λ(t). High-fidelity extraction of the waveform amplitude and phase lag is critical to successful sinusoidal analyses.


Assuntos
Encéfalo/citologia , Potenciais Evocados , Espaço Extracelular/fisiologia , Modelos Neurológicos , Técnicas de Rastreamento Neuroanatômico/métodos , Algoritmos , Animais , Encéfalo/fisiologia , Difusão , Espaço Extracelular/metabolismo , Marcadores do Trato Nervoso/farmacocinética , Compostos de Amônio Quaternário/farmacocinética , Ratos , Tempo de Reação
14.
J Neurophysiol ; 121(5): 1735-1747, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786223

RESUMO

Extracellular diffusion in the brain is customarily characterized by two parameters, the extracellular space (ECS) volume fraction α and the diffusion tortuosity λ. How these two parameters are temporarily modified and correlated in a physiological/pathological event remains unclear to date. Using tetramethylammonium (TMA+) as an ECS ion tracer in a newly updated iontophoretic sinusoidal method, we studied in this work the dynamic α(t) and λ(t) in rat somatosensory cortex during spreading depression (SD). Temporal variations of α(t) and λ(t), as evoked by SD, were obtained through analyses of the extracellular TMA+ diffusion waveform resulting from a sinusoidally modulated point source. Most of the time, cortical SD induced coordinated α(t) decreases and λ(t) increases. In rare occasions, SD induced sole decreases of α(t) with no changes in λ(t). The independent modulation of α(t) and λ(t) was neither associated with cortical anatomy nor with the specific shape of the SD field potential wave. Changes of α(t) and λ(t) often took place acutely at the onset of SD, followed by a more transient modulation. Compared with the prior iontophoretic methods of TMA+, the sinusoidal method provides time-resolved quantification of α(t) and λ(t) in relative terms but also raises a higher property requirement on the TMA+-selective microelectrode. The sinusoidal method could become a valuable tool in the studies of the dynamic ECS response in various brain events. NEW & NOTEWORTHY An iontophoretic sinusoidal method was applied to study the dynamic changes of two extracellular space parameters, the extracellular volume fraction α(t) and tortuosity λ(t), in the brain during cortical spreading depression. Both parameters showed coordinated (most often) and independent (rarely) modulations in spreading depression. The sinusoidal method is equally applicable to other acute pathological events and a valuable tool to study the functional role of extracellular space in brain events.


Assuntos
Córtex Cerebral/fisiologia , Depressão Alastrante da Atividade Elétrica Cortical , Espaço Extracelular/fisiologia , Algoritmos , Animais , Córtex Cerebral/citologia , Feminino , Masculino , Técnicas de Rastreamento Neuroanatômico/métodos , Marcadores do Trato Nervoso/farmacocinética , Neurônios/fisiologia , Compostos de Amônio Quaternário/farmacocinética , Ratos , Ratos Sprague-Dawley , Tempo de Reação
15.
Ophthalmology ; 126(4): 576-588, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30659849

RESUMO

PURPOSE: To evaluate the long-term visual outcomes and causes of vision loss in chronic central serous chorioretinopathy (CSC). DESIGN: Retrospective, longitudinal study. PARTICIPANTS: A total of 133 participants (217 eyes) with chronic CSC. METHODS: A retrospective review of clinical and multimodal imaging data of patients with chronic CSC managed by 3 of the authors between May 1977 and March 2018. Multimodal imaging comprised color photography, fluorescein angiography, indocyanine green angiography, fundus autofluorescence (FAF), and OCT. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA) at the final visit; change in BCVA between first visit and 1-, 5-, and 10-year follow-up visits; and causes of vision loss at final visit. RESULTS: Data from 6228 individual clinic visits were analyzed. Mean age of patients at the first visit was 60.7 years, and mean period of follow-up from first to last visit was 11.3 years. The cohort included 101 male patients (75.9%). At the final visit, 106 patients (79.7%) maintained driving-standard vision with BCVA of 20/40 or better in at least 1 eye, and 17 patients (12.8%) were legally blind with BCVA of 20/200 or worse in both eyes. Mean BCVA at first visit was not significantly different from mean BCVA at 1- or 5-year follow-up visits (both P ≥ 0.65) but was significantly better than the mean BCVA at the 10-year follow-up visit (P = 0.04). Seventy-nine percent of eyes with 20/40 or better vision at the first visit maintained the same level of vision at the 10-year follow-up visit. Ninety-two percent of eyes with 20/200 or worse vision at the first visit maintained the same level of vision at the 10-year follow-up visit. Cystoid macular degeneration, choroidal neovascularization (CNV), outer retinal disruption on OCT, and FAF changes were associated with poorer vision at the final visit (all P ≤ 0.001). Multivariable analysis revealed that greater age at first visit was associated with greater BCVA change at the 10-year follow-up visit (P = 0.001). CONCLUSIONS: Chronic CSC can be a sight-threatening disease leading to legal blindness. Age at presentation and outer retinal changes on multimodal imaging were associated with long-term BCVA changes and may be predictors of long-term visual outcomes.


Assuntos
Coriorretinopatia Serosa Central/complicações , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Coriorretinopatia Serosa Central/diagnóstico por imagem , Coriorretinopatia Serosa Central/fisiopatologia , Neovascularização de Coroide/etiologia , Neovascularização de Coroide/fisiopatologia , Doença Crônica , Corantes/administração & dosagem , Feminino , Angiofluoresceinografia , Humanos , Verde de Indocianina/administração & dosagem , Estudos Longitudinais , Edema Macular/etiologia , Edema Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Imagem Óptica , Fotografação , Degeneração Retiniana/etiologia , Degeneração Retiniana/fisiopatologia , Estudos Retrospectivos , Transtornos da Visão/diagnóstico por imagem , Transtornos da Visão/etiologia
16.
Surv Ophthalmol ; 64(4): 579-583, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29024674

RESUMO

A 68-year-old woman with a recent history of blurring in the left eye had undergone mastectomy for breast cancer 20 years ago. A series of bone metastases started 5 years after her diagnosis. Examination of the optic nerve head of the left eye revealed an isolated peripapillary mass. Indocyanine green angiography displayed vessels within the mass, and fluorescein angiography demonstrated hyperfluorescence of the mass from vascular leakage plus lobular spots of blocked fluorescence. B-scan ultrasound revealed a hyperechoic-elevated nodular mass on the optic disc. Spectral-domain optical coherence tomography displayed a mass of spherules. Magnetic resonance imaging of the brain demonstrated metastatic tumors. She was diagnosed with an optic disk metastasis from her breast carcinoma.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/secundário , Neoplasias do Nervo Óptico/secundário , Idoso , Feminino , Humanos
17.
Surv Ophthalmol ; 64(1): 117-122, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28684101

RESUMO

A 54-year-old white man presented with a "blind spot" temporally in his left eye. Best-corrected visual acuity in the affected eye was 20/20, and Humphrey visual field revealed an enlarged blind spot. Funduscopic examination revealed subtle peripapillary pigmentary changes corresponding to a well-demarcated peripapillary region of hyperautofluorescence and hypoautofluorescence on fundus autofluorescence. Outer retinal degenerative changes were detected on spectral-domain optical coherence tomography. A diagnosis of acute zonal occult outer retinopathy was made based on clinical history and imaging studies.


Assuntos
Retina/patologia , Escotoma/diagnóstico , Campos Visuais/fisiologia , Angiofluoresceinografia , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Escotoma/fisiopatologia , Tomografia de Coerência Óptica/métodos , Testes de Campo Visual , Síndrome dos Pontos Brancos
18.
Retina ; 39(7): 1333-1342, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29554078

RESUMO

PURPOSE: To compare retinal pathology visualization in multispectral scanning laser ophthalmoscope imaging between the Spectralis and Optos devices. METHODS: This retrospective cross-sectional study included 42 eyes from 30 patients with age-related macular degeneration (19 eyes), diabetic retinopathy (10 eyes), and epiretinal membrane (13 eyes). All patients underwent retinal imaging with a color fundus camera (broad-spectrum white light), the Spectralis HRA-2 system (3-color monochromatic lasers), and the Optos P200 system (2-color monochromatic lasers). The Optos image was cropped to a similar size as the Spectralis image. Seven masked graders marked retinal pathologies in each image within a 5 × 5 grid that included the macula. RESULTS: The average area with detected retinal pathology in all eyes was larger in the Spectralis images compared with Optos images (32.4% larger, P < 0.0001), mainly because of better visualization of epiretinal membrane and retinal hemorrhage. The average detection rate of age-related macular degeneration and diabetic retinopathy pathologies was similar across the three modalities, whereas epiretinal membrane detection rate was significantly higher in the Spectralis images. CONCLUSION: Spectralis tricolor multispectral scanning laser ophthalmoscope imaging had higher rate of pathology detection primarily because of better epiretinal membrane and retinal hemorrhage visualization compared with Optos bicolor multispectral scanning laser ophthalmoscope imaging.


Assuntos
Angiofluoresceinografia/métodos , Oftalmoscopia/métodos , Retina/patologia , Doenças Retinianas/diagnóstico , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos
19.
Retina ; 39(10): 1936-1944, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30028411

RESUMO

PURPOSE: To characterize the natural history and response of age-related macular degeneration-associated peripapillary choroidal neovascularization to anti-vascular endothelial growth factor therapy. METHODS: This was a retrospective case series of patients with peripapillary choroidal neovascularization secondary to neovascular age-related macular degeneration. All patients underwent complete ophthalmologic examination and retinal imaging including fluorescein angiography and spectral domain optical coherence tomography at each visit. Eyes with subretinal or intraretinal macular fluid were treated with anti-vascular endothelial growth factor monotherapy using a modified as-needed treatment algorithm. RESULTS: Thirty-three eyes of 27 patients were included. The median age was 82 years (range, 62-94), and the median duration of follow-up was 65 months (range, 6-165). Fourteen eyes (58%) without fovea-involving fluid at baseline subsequently developed exudation after a median observation period of 16 months (range, 4-107). Ten of 24 eyes (42%) without initial macular fluid remained dry during the entire follow-up. The median number of injections required until complete fluid reabsorption was 3 (range, 1-21) during the first treatment cycle. The median time to fluid recurrence was 6 months (range, 3-74). CONCLUSION: Peripapillary choroidal neovascularization secondary to wet age-related macular degeneration has a slow progression, may not require treatment for a prolonged period, and responds rapidly to anti-vascular endothelial growth factor treatment with good visual outcomes.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Angiofluoresceinografia/métodos , Ranibizumab/administração & dosagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Neovascularização de Coroide/diagnóstico , Feminino , Seguimentos , Fundo de Olho , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Degeneração Macular Exsudativa/diagnóstico
20.
Retina ; 39(10): 2022-2031, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30015764

RESUMO

PURPOSE: To assess early retinal microvascular and functional changes in diabetic patients without clinical evidence of diabetic retinopathy with optical coherence tomography angiography and central visual analyzer. METHODS: This was an observational case-control study of diabetic patients without diabetic retinopathy and nondiabetic controls. Patients underwent optical coherence tomography angiography imaging and visual acuity testing using the central visual analyzer. The foveal avascular zone area and the capillary density in the superficial and deep capillary plexuses were measured manually by a masked grader. RESULTS: Sixty eyes from 35 diabetic patients were included in the study group, and 45 eyes from 31 nondiabetic patients were included in the control group. The foveal avascular zone area was not significantly different between the diabetic group and controls (both P > 0.05). The mean capillary density in the deep capillary plexus was significantly lower in diabetic eyes compared with control eyes (P = 0.04). The mean visual acuity in all central visual analyzer modules was significantly decreased in diabetic patients compared with controls (all P < 0.05). CONCLUSION: Optical coherence tomography angiography was able to detect retinal microvascular changes in the deep capillary plexus, and the central visual analyzer showed signs of decreased visual acuity under conditions simulating suboptimal contrast and glare in diabetic patients without diabetic retinopathy.


Assuntos
Diabetes Mellitus/diagnóstico , Angiofluoresceinografia/métodos , Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/fisiopatologia , Retinopatia Diabética , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos
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