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1.
PLoS One ; 15(10): e0240509, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052969

RESUMO

PURPOSE: To evaluate see-through Augmented Reality Digital spectacles (AR DSpecs) for improving the mobility of patients with peripheral visual field (VF) losses when tested on a walking track. DESIGN: Prospective Case Series. PARTICIPANTS: 21 patients with peripheral VF defects in both eyes, with the physical ability to walk without assistance. METHODS: We developed the AR DSpecs as a wearable VF aid with an augmented reality platform. Image remapping algorithms produced personalized visual augmentation in real time based on the measured binocular VF with the AR DSpecs calibration mode. We tested the device on a walking track to determine if patients could more accurately identify peripheral objects. MAIN OUTCOME MEASURES: We analyzed walking track scores (number of recognized/avoided objects) and eye tracking data (six gaze parameters) to measure changes in the kinematic and eye scanning behaviors while walking, and assessed a possible placebo effect by deactivating the AR DSpecs remapping algorithms in random trials. RESULTS: Performance, judged by the object detection scores, improved with the AR DSpecs (P<0.001, Wilcoxon rank sum test) with an average improvement rate of 18.81%. Two gaze parameters improved with the activated algorithm (P<0.01, paired t-test), indicating a more directed gaze on the central path with less eye scanning. Determination of the binocular integrated VF with the DSpecs correlated with the integrated standard automated perimetry (R = 0.86, P<0.001), mean sensitivity difference 0.8 ± 2.25 dB (Bland-Altman). CONCLUSIONS: AR DSpecs may improve walking maneuverability of patients with peripheral VF defects by enhancing detection of objects in a testing environment.


Assuntos
Transtornos da Visão/reabilitação , Campos Visuais/fisiologia , Caminhada/fisiologia , Algoritmos , Óculos , Feminino , Humanos , Masculino , Estudos Prospectivos , Realidade Virtual , Transtornos da Visão/fisiopatologia , Testes de Campo Visual
2.
Am J Ophthalmol ; 210: 48-58, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31678558

RESUMO

PURPOSE: To evaluate the performance of 3-dimensional (3D) endothelium/Descemet membrane complex thickness (En/DMT) maps vs total corneal thickness (TCT) maps in the diagnosis of active corneal graft rejection. DESIGN: Cross-sectional study. METHODS: Eighty-one eyes (32 clear grafts and 17 with active rejection, along with 32 age-matched control eyes) were imaged using high-definition optical coherence tomography (HD-OCT), and a custom-built segmentation algorithm was used to generate 3D color-coded maps of TCT and En/DMT of the central 6-mm cornea. Regional En/DMT and TCT were analyzed and compared between the studied groups. Receiver operating characteristic curves were used to determine the accuracy of En/DMT and TCT maps in differentiating between studied groups. Main outcome measures were regional En/DMT and TCT. RESULTS: Both regional TCT and En/DMT were significantly greater in actively rejecting grafts compared to both healthy corneas and clear grafts (P < .001). Using 3D thickness maps, central, paracentral, and peripheral En/DMT achieved 100% sensitivity and 100% specificity in diagnosing actively rejecting grafts (optimal cut-off value [OCV] of 19 µm, 24 µm, and 26 µm, respectively), vs only 82% sensitivity and 96% specificity for central TCT, OCV of 587 µm. Moreover, central, paracentral, and peripheral En/DMT correlated significantly with graft rejection severity (r = 0.972, r = 0.729, and r = 0.823, respectively; P < .001). CONCLUSION: 3D En/DMT maps can diagnose active corneal graft rejection with excellent accuracy, sensitivity, and specificity. Future longitudinal studies are required to evaluate the predictive and prognostic role of 3D En/DMT maps in corneal graft rejection.


Assuntos
Doenças da Córnea/cirurgia , Transplante de Córnea , Lâmina Limitante Posterior/patologia , Endotélio Corneano/patologia , Rejeição de Enxerto/diagnóstico , Adulto , Idoso , Análise de Variância , Estudos Transversais , Feminino , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica/métodos , Adulto Jovem
3.
J Clin Neurophysiol ; 32(3): e12-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25761260

RESUMO

PURPOSE: To evaluate the use of the cortiQ-based mapping system (g.tec medication engineering GmbH, Austria) for real-time functional mapping (RTFM) and to compare it to results from electrical cortical stimulation mapping (ESM) and functional magnetic resonance imaging (fMRI). METHODS: Electrocorticographic activity was recorded in 3 male patients with intractable epilepsy by using cortiQ mapping system and analyzed in real time. Activation related to motor, sensory, and receptive language tasks was determined by evaluating the power of the high gamma frequency band (60-170 Hz). The sensitivity and specificity of RTFM were tested against ESM and fMRI results. RESULTS: "Next-neighbor" approach demonstrated [sensitivity/specificity %] (1) RTFM against ESM: 100.00/79.70 for hand motor; 100.00/73.87 for hand sensory; -/87 for language (it was not identified by the ESM); (2) RTFM against fMRI: 100.00/84.4 for hand motor; 66.70/85.35 for hand sensory; and 87.85/77.70 for language. CONCLUSIONS: The results of the quantitative "next-neighbor" RTFM evaluation were concordant to those from ESM and fMRI. The RTFM correlates well with localization of hand motor function provided by ESM and fMRI, which may offer added localization in the operating room and guidance for extraoperative ESM mapping. Real-time functional mapping correlates with fMRI language activation when ESM findings are negative. It has fewer limitations than ESM and greater flexibility in activation paradigms and measuring responses.


Assuntos
Mapeamento Encefálico/métodos , Sistemas Computacionais , Eletrocorticografia/métodos , Epilepsia/cirurgia , Adolescente , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Modelagem Computacional Específica para o Paciente , Software , Tomografia Computadorizada por Raios X , Adulto Jovem
4.
J Neurosurg Pediatr ; 14(3): 287-95, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24995815

RESUMO

Accurate language localization expands surgical treatment options for epilepsy patients and reduces the risk of postsurgery language deficits. Electrical cortical stimulation mapping (ESM) is considered to be the clinical gold standard for language localization. While ESM affords clinically valuable results, it can be poorly tolerated by children, requires active participation and compliance, carries a risk of inducing seizures, is highly time consuming, and is labor intensive. Given these limitations, alternative and/or complementary functional localization methods such as analysis of electrocorticographic (ECoG) activity in high gamma frequency band in real time are needed to precisely identify eloquent cortex in children. In this case report, the authors examined 1) the use of real-time functional mapping (RTFM) for language localization in a high gamma frequency band derived from ECoG to guide surgery in an epileptic pediatric patient and 2) the relationship of RTFM mapping results to postsurgical language outcomes. The authors found that RTFM demonstrated relatively high sensitivity (75%) and high specificity (90%) when compared with ESM in a "next-neighbor" analysis. While overlapping with ESM in the superior temporal region, RTFM showed a few other areas of activation related to expressive language function, areas that were eventually resected during the surgery. The authors speculate that this resection may be associated with observed postsurgical expressive language deficits. With additional validation in more subjects, this finding would suggest that surgical planning and associated assessment of the risk/benefit ratio would benefit from information provided by RTFM mapping.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiopatologia , Estimulação Elétrica , Eletroencefalografia , Epilepsias Parciais/cirurgia , Idioma , Fala , Adolescente , Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Epilepsias Parciais/fisiopatologia , Feminino , Humanos , Testes Neuropsicológicos , Sensibilidade e Especificidade
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