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[PMID]:29230977
[Au] Autor:Jo J; Moon BG; Lee JY
[Ad] Endereço:Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
[Ti] Título:Scleral Buckling Using a Non-contact Wide-Angle Viewing System with a 25-Gauge Chandelier Endoilluminator.
[So] Source:Korean J Ophthalmol;31(6):533-537, 2017 Dec.
[Is] ISSN:2092-9382
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:PURPOSE: To report the outcome of scleral buckling using a non-contact wide-angle viewing system with a 25-gauge chandelier endoilluminator. METHODS: Retrospective analyses of medical records were performed for 17 eyes of 16 patients with primary rhegmatogenous retinal detachment (RRD) without proliferative vitreoretinopathy who had undergone conventional scleral buckling with cryoretinopexy using the combination of a non-contact wide-angle viewing system and chandelier endoillumination. RESULTS: The patients were eight males and five females with a mean age of 26.8 ± 10.2 (range, 11 to 47) years. The mean follow-up period was 7.3 ± 3.1 months. Baseline best-corrected visual acuity was 0.23 ± 0.28 logarithm of the minimum angle of resolution units. Best-corrected visual acuity at the final visit showed improvement (0.20 ± 0.25 logarithm of the minimum angle of resolution units), but the improvement was not statistically significant (p = 0.722). As a surgery-related complication, there was vitreous loss at the end of surgery in one eye. As a postoperative complication, increased intraocular pressure (four cases) and herpes simplex epithelial keratitis (one case) were controlled postoperatively with eye drops. One case of persistent RRD after primary surgery needed additional vitrectomy, and the retina was postoperatively attached. CONCLUSIONS: Scleral buckling with chandelier illumination as a surgical technique for RRD has the advantages of relieving the surgeon's neck pain from prolonged use of the indirect ophthalmoscope and sharing the surgical procedure with another surgical team member. In addition, fine retinal breaks that are hard to identify using an indirect ophthalmoscope can be easily found under the microscope by direct endoillumination.
[Mh] Termos MeSH primário: Iluminação/instrumentação
Oftalmoscópios
Descolamento Retiniano/cirurgia
Recurvamento da Esclera/instrumentação
[Mh] Termos MeSH secundário: Adolescente
Adulto
Criança
Desenho de Equipamento
Feminino
Seguimentos
Seres Humanos
Masculino
Meia-Idade
Descolamento Retiniano/diagnóstico
Estudos Retrospectivos
Cirurgia Assistida por Computador
Fatores de Tempo
Acuidade Visual
Vitreorretinopatia Proliferativa
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE
[do] DOI:10.3341/kjo.2017.0044


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[PMID]:29079858
[Au] Autor:Blair NP; Wanek J; Felder AE; Joslin CE; Kresovich JK; Lim JI; Chau FY; Leiderman Y; Shahidi M
[Ad] Endereço:Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois, United States.
[Ti] Título:Retinal Oximetry and Vessel Diameter Measurements With a Commercially Available Scanning Laser Ophthalmoscope in Diabetic Retinopathy.
[So] Source:Invest Ophthalmol Vis Sci;58(12):5556-5563, 2017 Oct 01.
[Is] ISSN:1552-5783
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Purpose: To test the hypothesis that retinal vascular diameter and hemoglobin oxygen saturation alterations, according to stages of diabetic retinopathy (DR), are discernible with a commercially available scanning laser ophthalmoscope (SLO). Methods: One hundred eighty-one subjects with no diabetes (No DM), diabetes with no DR (No DR), nonproliferative DR (NPDR), or proliferative DR (PDR, all had photocoagulation) underwent imaging with an SLO with dual lasers (532 nm and 633 nm). Customized image analysis software determined the diameters of retinal arteries and veins (DA and DV) and central retinal artery and vein equivalents (CRAE and CRVE). Oxygen saturations of hemoglobin in arteries and veins (SO2A and SO2V) were estimated from optical densities of vessels on images at the two wavelengths. Statistical models were generated by adjusting for effects of sex, race, age, eye, and fundus pigmentation. Results: DA, CRAE, and CRVE were reduced in PDR compared to No DM (P ≤ 0.03). DV and CRVE were similar between No DM and No DR, but they were higher in NPDR than No DR (P ≤ 0.01). Effect of stage of disease on SO2A differed by race, being increased relative to No DM in NPDR and PDR in Hispanic participants only (P ≤ 0.02). Relative to No DM, SO2V was increased in NPDR and PDR (P ≤ 0.05). Conclusions: Alterations in retinal vascular diameters and SO2 by diabetic retinopathy stage can be detected with a widely available SLO, and covariates such as race can influence the results.
[Mh] Termos MeSH primário: Retinopatia Diabética/diagnóstico
Oftalmoscópios
Oximetria/métodos
Consumo de Oxigênio
Oxigênio/metabolismo
Vasos Retinianos/diagnóstico por imagem
[Mh] Termos MeSH secundário: Adulto
Idoso
Retinopatia Diabética/metabolismo
Desenho de Equipamento
Feminino
Hemoglobinas/metabolismo
Seres Humanos
Masculino
Meia-Idade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hemoglobins); S88TT14065 (Oxygen)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171029
[St] Status:MEDLINE
[do] DOI:10.1167/iovs.17-21934


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[PMID]:28525557
[Au] Autor:Luo T; Gast TJ; Vermeer TJ; Burns SA
[Ad] Endereço:School of Optometry, Indiana University, Bloomington, Indiana, United States.
[Ti] Título:Retinal Vascular Branching in Healthy and Diabetic Subjects.
[So] Source:Invest Ophthalmol Vis Sci;58(5):2685-2694, 2017 May 01.
[Is] ISSN:1552-5783
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Purpose: To measure the effect of nonproliferative diabetic retinopathy (NPDR) on retinal branching. To compare vascular branching in healthy and diabetic subjects with established biophysical models. Methods: Vascular bifurcations in arteries and veins were imaged in 17 NPDR and 26 healthy subjects with the Indiana adaptive optics scanning laser ophthalmoscope (AOSLO). Vessel measurements were grouped according to parent vessel diameters into large (≤50 ∼ <100 µm) and small (≤20 ∼ <50 µm) sizes. Vessel diameters and bifurcation angles were measured manually. Vascular diameters were compared with predictions of Murray's law using curve fitting. For analysis of bifurcation angles, two models from Zamir were compared: one based on the power required for blood pumping, the other based on drag force between blood and vascular wall. Results: For normal larger vessels, the exponent relating the parent and daughter branching diameters was significantly less than the value of 3 predicted by Murray's law (arteries: 2.59; veins: 1.95). In NPDR, the best-fit exponent was close to 3 for arteries but close to 2 in healthy subjects in veins, (arteries: 3.09; veins: 2.16). For both small arteries and veins, diabetics' exponent differed from healthy subjects (P < 0.01). Bifurcation angles in the healthy subjects (78° ± with a standard error (SE) of 0.9°) were not much different than in NPDR (79° ± SE 1.3°). The model based on minimizing pumping power predicted the measurements better than the one minimizing the vascular drag and lumen surface area. Conclusions: The relation between parent and daughter branch diameters changes in diabetes, but the branching angles do not.
[Mh] Termos MeSH primário: Retinopatia Diabética/fisiopatologia
Artéria Retiniana/patologia
Neovascularização Retiniana/patologia
Veia Retiniana/patologia
[Mh] Termos MeSH secundário: Adulto
Arteríolas/anatomia & histologia
Arteríolas/patologia
Feminino
Voluntários Saudáveis
Seres Humanos
Masculino
Microscopia Confocal
Meia-Idade
Oftalmoscópios
Artéria Retiniana/anatomia & histologia
Veia Retiniana/anatomia & histologia
Vênulas/anatomia & histologia
Vênulas/patologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170917
[Lr] Data última revisão:
170917
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170520
[St] Status:MEDLINE
[do] DOI:10.1167/iovs.17-21653


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[PMID]:28369065
[Au] Autor:Bedggood P; Metha A
[Ad] Endereço:Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia.
[Ti] Título:De-warping of images and improved eye tracking for the scanning laser ophthalmoscope.
[So] Source:PLoS One;12(4):e0174617, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A limitation of scanning laser ophthalmoscopy (SLO) is that eye movements during the capture of each frame distort the retinal image. Various sophisticated strategies have been devised to ensure that each acquired frame can be mapped quickly and accurately onto a chosen reference frame, but such methods are blind to distortions in the reference frame itself. Here we explore a method to address this limitation in software, and demonstrate its accuracy. We used high-speed (200 fps), high-resolution (~1 µm), flood-based imaging of the human retina with adaptive optics to obtain "ground truth" information on the retinal image and motion of the eye. This information was used to simulate SLO video sequences at 20 fps, allowing us to compare various methods for eye-motion recovery and subsequent minimization of intra-frame distortion. We show that a) a single frame can be near-perfectly recovered with perfect knowledge of intra-frame eye motion; b) eye motion at a given time point within a frame can be accurately recovered by tracking the same strip of tissue across many frames, due to the stochastic symmetry of fixational eye movements. This approach is similar to, and easily adapted from, previously suggested strip-registration approaches; c) quality of frame recovery decreases with amplitude of eye movements, however, the proposed method is affected less by this than other state-of-the-art methods and so offers even greater advantages when fixation is poor. The new method could easily be integrated into existing image processing software, and we provide an example implementation written in Matlab.
[Mh] Termos MeSH primário: Movimentos Oculares/fisiologia
Processamento de Imagem Assistida por Computador/métodos
Oftalmoscópios
Oftalmoscopia/métodos
Retina/diagnóstico por imagem
[Mh] Termos MeSH secundário: Fixação Ocular
Seres Humanos
Processamento de Imagem Assistida por Computador/instrumentação
Software
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170404
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174617


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[PMID]:28355660
[Au] Autor:Reiniger JL; Domdei N; Pfau M; Müller PL; Holz FG; Harmening WM
[Ad] Endereço:Universitäts-Augenklinik Bonn, Universitätsklinikum Bonn.
[Ti] Título:[Potential of Adaptive Optics for the Diagnostic Evaluation of Hereditary Retinal Diseases].
[Ti] Título:Adaptive Optiken ­ Möglichkeiten für die Diagnostik hereditärer Netzhauterkrankungen..
[So] Source:Klin Monbl Augenheilkd;234(3):311-319, 2017 Mar.
[Is] ISSN:1439-3999
[Cp] País de publicação:Germany
[La] Idioma:ger
[Ab] Resumo:The use of adaptive optics in ophthalmoscopy is a breakthrough technological achievement. With AO ophthalmoscopes, the microscopic retinal structure can be visualised non-invasively and on a cellular level, allowing for cellular scale imaging of the retinal nerve fibre layer, the smallest retinal capillaries, rod and cone photoreceptors, and the retinal pigment epithelium mosaic in the living subject. Regarding the diagnostic evaluation of retinal diseases, the current research focuses on monogenetic retinal diseases, which - when better understood - may allow for conclusions to be drawn about other multifactorial diseases and their underlying mechanisms (model disease). For disease monitoring and current and future pharmacological intervention (e.g. gene therapy), they will help to better establish novel and reliable clinical endpoints. New AO imaging devices have just become commercially available, and the number of retinal pathologies visualised with AO is increasing. Recently, an AO-based microstimulation technique has been introduced, which offers the possibility to directly correlate retinal structure with visual function on a cellular level.
[Mh] Termos MeSH primário: Oftalmopatias Hereditárias/diagnóstico
Lentes
Oftalmoscópios
Distrofias Retinianas/diagnóstico
Distrofias Retinianas/genética
[Mh] Termos MeSH secundário: Estimulação Elétrica/instrumentação
Desenho de Equipamento
Medicina Baseada em Evidências
Seres Humanos
Aumento da Imagem/instrumentação
Dispositivos Ópticos
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170330
[St] Status:MEDLINE
[do] DOI:10.1055/s-0043-100631


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[PMID]:28234351
[Au] Autor:Yusuf IH; Barnes JK; Fung TH; Elston JS; Patel CK; Medscape
[Ad] Endereço:The Oxford Eye Hospital, West Wing, John Radcliffe Hospital, Oxford, UK.
[Ti] Título:Non-contact ultra-widefield retinal imaging of infants with suspected abusive head trauma.
[So] Source:Eye (Lond);31(3):353-363, 2017 Mar.
[Is] ISSN:1476-5454
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PurposeThe purpose of the study was to audit the use of non-contact ultra-widefield retinal imaging in infants with suspected abusive head trauma (AHT) using the Optos P200MA Scanning Laser Ophthalmoscope.Patients and methodsA retrospective, observational case series. Ten eyes of five consecutive infants (aged 1-15 months) with suspected (or in 1 case, known) AHT referred for an ophthalmological opinion were included. Each infant underwent non-contact ultra-widefield retinal imaging using the Optos P200MA scanning laser ophthalmoscope. Optos fundus fluorescein angiography (FFA) was performed in one infant with oral sedation. The other four infants did not require sedation. The main outcome measure was the acquisition of a single, definitive ultra-widefield retinal image in each eye. Safety was audited by determining adverse changes in heart rate and oxygen saturations that required cessation of imaging.ResultsThe Optos P200MA ultra-widefield scanning laser ophthalmoscope acquired good quality retinal images in all infants. Documentation of acute, widespread retinal haemorrhages contributed to a diagnosis of AHT in three infants. Chronic pre-macular haemorrhage and macular schisis were documented by FFA in a fourth infant. The absence of retinal haemorrhages was documented in a fifth infant contributing to the exclusion of a diagnosis of AHT. There were no adverse safety signals in any infant in this series.ConclusionThe Optos P200MA ultra-widefield scanning laser ophthalmoscope appears safe to use in infants with suspected AHT, providing high-quality retinal images in a single frame without ocular contact. Optos P200MA may be used as alternative to RetCam to document retinal haemorrhages in stable infants with suspected AHT.
[Mh] Termos MeSH primário: Maus-Tratos Infantis/diagnóstico
Traumatismos Craniocerebrais/diagnóstico
Oftalmoscopia/métodos
Retina/diagnóstico por imagem
Hemorragia Retiniana/diagnóstico por imagem
[Mh] Termos MeSH secundário: Auditoria Clínica
Traumatismos Craniocerebrais/etiologia
Feminino
Angiofluoresceinografia
Seres Humanos
Lactente
Masculino
Oftalmoscópios
Hemorragia Retiniana/etiologia
Estudos Retrospectivos
[Pt] Tipo de publicação:JOURNAL ARTICLE; OBSERVATIONAL STUDY
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170718
[Lr] Data última revisão:
170718
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170225
[St] Status:MEDLINE
[do] DOI:10.1038/eye.2017.2


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[PMID]:28194486
[Au] Autor:Reiniger JL; Domdei N; Holz FG; Harmening WM
[Ad] Endereço:Universitäts-Augenklinik Bonn, Ernst-Abbe-Str. 2, 53127, Bonn, Deutschland. jenny.reiniger@ukbonn.de.
[Ti] Título:[Technical principles of adaptive optics in ophthalmology].
[Ti] Título:Technische Grundlagen adaptiver Optiken in der Ophthalmologie..
[So] Source:Ophthalmologe;114(3):198-205, 2017 Mar.
[Is] ISSN:1433-0423
[Cp] País de publicação:Germany
[La] Idioma:ger
[Ab] Resumo:During the last 25 years ophthalmic imaging has undergone a revolution. This review gives an overview of the possibilities of adaptive optics (AO) for ophthalmic imaging technologies and their development and illustrates that the role of ophthalmic imaging changed from the documentation of obvious abnormalities to the detection of microscopic yet significant conspicuities. This enables earlier and more precise diagnoses. The implementation of AO for imaging systems like fundus cameras, scanning laser ophthalmoscopy and optical coherence tomography has gained in importance. In recent years a couple of companies started developing commercially available AO systems, thus, indicating a future use in clinical routine.
[Mh] Termos MeSH primário: Angiofluoresceinografia/instrumentação
Aumento da Imagem/instrumentação
Lentes
Microscopia Confocal/instrumentação
Oftalmoscópios
Fotografia/instrumentação
Tomografia de Coerência Óptica/instrumentação
[Mh] Termos MeSH secundário: Desenho de Equipamento
Análise de Falha de Equipamento
Angiofluoresceinografia/métodos
Microscopia Confocal/métodos
Oftalmoscopia/métodos
Fotografia/métodos
Avaliação da Tecnologia Biomédica
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170215
[St] Status:MEDLINE
[do] DOI:10.1007/s00347-017-0440-z


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[PMID]:27995325
[Au] Autor:Domdei N; Reiniger JL; Pfau M; Charbel Issa P; Holz FG; Harmening WM
[Ad] Endereço:Universitäts-Augenklinik Bonn, Bonn, Deutschland. Niklas.Domdei@ukb.uni-bonn.de.
[Ti] Título:[Histology of the living eye : Noninvasive microscopic structure and functional analysis of the retina with adaptive optics].
[Ti] Título:Histologie im lebenden Auge : Nichtinvasive mikroskopische Struktur- und Funktionsanalyse der Netzhaut mit adaptiven Optiken..
[So] Source:Ophthalmologe;114(3):206-214, 2017 Mar.
[Is] ISSN:1433-0423
[Cp] País de publicação:Germany
[La] Idioma:ger
[Ab] Resumo:Equipping an ophthalmoscope with adaptive optics (AO) offers access to the living human retina with unprecedented spatial resolution. With AO, cellular structures such as the nerve fiber layer, the microvasculature of the smallest retinal capillaries, rod and cone photoreceptors and the mosaic of the retinal pigment epithelium are directly observable. A large number of studies in the normal and diseased retina have already shown that this level of detail offers new insights into disease mechanisms and progression, and promises to identify early disease markers. In conjunction with functional testing of single photoreceptors that is possible with AO microstimulation, a structure-function relationship on the cellular scale is within reach. These technological advances offer new avenues for clinical ophthalmology, interventional efforts, and basic research of the function and dysfunction of vision.
[Mh] Termos MeSH primário: Aumento da Imagem/instrumentação
Lentes
Microscopia/instrumentação
Neuroimagem/instrumentação
Oftalmoscópios
Retina/citologia
[Mh] Termos MeSH secundário: Desenho de Equipamento
Análise de Falha de Equipamento
Avaliação da Tecnologia Biomédica
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161221
[St] Status:MEDLINE
[do] DOI:10.1007/s00347-016-0411-9


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[PMID]:27793592
[Au] Autor:Elsner AE; Chui TY; Feng L; Song HX; Papay JA; Burns SA
[Ad] Endereço:Indiana University School of Optometry, 800 E. Atwater Ave, Bloomington, IN 47405, United States. Electronic address: aeelsner@indiana.edu.
[Ti] Título:Distribution differences of macular cones measured by AOSLO: Variation in slope from fovea to periphery more pronounced than differences in total cones.
[So] Source:Vision Res;132:62-68, 2017 Mar.
[Is] ISSN:1878-5646
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Large individual differences in cone densities occur even in healthy, young adults with low refractive error. We investigated whether cone density follows a simple model that some individuals have more cones, or whether individuals differ in both number and distribution of cones. We quantified cones in the eyes of 36 healthy young adults with low refractive error using a custom adaptive optics scanning laser ophthalmoscope. The average cone density in the temporal meridian was, for the mean±SD, 43,216±6039, 27,466±3496, 14,996±1563, and 12,207±1278cones/mm for 270, 630, 1480, and 2070µm from the foveal center. Cone densities at 630µm retinal eccentricity were uncorrelated to those at 2070µm, ruling out models with a constant or proportional relation of cone density to eccentricity. Subjects with high central macula cone densities had low peripheral cone densities. The cone density ratio (2070:630µm) was negatively correlated with cone density at 630µm, consistent with variations in the proportion of peripheral cones migrating towards the center. We modelled the total cones within a central radius of 7deg, using the temporal data and our published cone densities for temporal, nasal, superior, and inferior meridians. We computed an average of 221,000 cones. The coefficient of variation was 0.0767 for total cones, but higher for samples near the fovea. Individual differences occur both in total cones and other developmental factors related to cone distribution.
[Mh] Termos MeSH primário: Fóvea Central/citologia
Retina/citologia
Células Fotorreceptoras Retinianas Cones/citologia
[Mh] Termos MeSH secundário: Adolescente
Adulto
Contagem de Células
Feminino
Seres Humanos
Masculino
Oftalmoscópios
Oftalmoscopia
Acuidade Visual
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161108
[St] Status:MEDLINE


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[PMID]:27249824
[Au] Autor:Rohrbach D; Jakob A; Lloyd HO; Tretbar SH; Silverman RH; Mamou J
[Ti] Título:A Novel Quantitative 500-MHz Acoustic Microscopy System for Ophthalmologic Tissues.
[So] Source:IEEE Trans Biomed Eng;64(3):715-724, 2017 Mar.
[Is] ISSN:1558-2531
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: This paper describes development of a novel 500-MHz scanning acoustic microscope (SAM) for assessing the mechanical properties of ocular tissues at fine resolution. The mechanical properties of some ocular tissues, such as lamina cribrosa (LC) in the optic nerve head, are believed to play a pivotal role in eye pathogenesis. METHODS: A novel etching technology was used to fabricate silicon-based lens for a 500-MHz transducer. The transducer was tested in a custom-designed scanning system on human eyes. Two-dimensional (2-D) maps of bulk modulus (K) and mass density (ρ) were derived using improved versions of current state-of-the-art signal processing approaches. RESULTS: The transducer employed a lens radius of 125 µm and had a center frequency of 479 MHz with a -6-dB bandwidth of 264 MHz and a lateral resolution of 4 µm. The LC, Bruch's membrane (BM) at the interface of the retina and choroid, and Bowman's layer (BL) at the interface of the corneal epithelium and stroma, were successfully imaged and resolved. Analysis of the 2-D parameter maps revealed average values of LC, BM, and BL with KLC = 2.81 ±0.17; GPa, KBM = 2.89 ±0.18; GPa, KBL = 2.6 ±0.09 ; GPa, ρ LC = 0.96 ±0.03 g/cm ; ρ BM = 0.97 ±0.04 g/cm ; ρ BL = 0.98 ±0.04 g/cm . SIGNIFICANCE: This novel SAM was shown to be capable of measuring mechanical properties of soft biological tissues at microscopic resolution; it is currently the only system that allows simultaneous measurement of K, ρ, and attenuation in large lateral scales (field area >9 mm ) and at fine resolutions.
[Mh] Termos MeSH primário: Aumento da Imagem/instrumentação
Lentes
Microscopia Acústica/instrumentação
Oftalmoscópios
Retina/citologia
Retina/diagnóstico por imagem
[Mh] Termos MeSH secundário: Desenho de Equipamento
Análise de Falha de Equipamento
Seres Humanos
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
Transdutores
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170714
[Lr] Data última revisão:
170714
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160602
[St] Status:MEDLINE
[do] DOI:10.1109/TBME.2016.2573682



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