1998 — 2001 |
Milne, Peter Parel, Jean-Marie (co-PI) [⬀] Manns, Fabrice Rol, Pascal |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Instrumentation and Laboratory Enhancement in Biomedical Optics
We are requesting funds to purchase instruments that will be used to improve our undergraduate biomedical optics laboratory and curriculum. Our overall objective is to develop a two-semester undergraduate laboratory course in optics and lasers emphasizing their applications in medicine to better train undergraduate students at solving practical design and engineering problems in biomedical optics. In addition to classical optical teaching experiments, the laboratory courses will include representative design problems in medical optic and laser applications, with an emphasis on medical laser and light delivery systems and laser-tissue interactions. The laboratory courses will serve as a practical yet instructional introduction to optics, fiber optics, lasers and their application in the medical sciences. The courses are intended for sophomore or junior undergraduate biomedical engineering students. By providing this introductory practical experience, we will be able to improve the content of two existing classes on biomedical optics currently offered to advanced undergraduate students. We expect that this project will improve the achievements of our undergraduate students later involved in design projects in biomedical optics and also serve as a model for undergraduate programs in biomedical optics currently being developed at other universities nationwide. The results of the project so be used to develop additional undergraduate teaching materials and exercises in biomedical optics that may be others outside of our institution.
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1 |
2007 — 2010 |
Magleby, Karl (co-PI) [⬀] Leblanc, Roger (co-PI) [⬀] Moy, Vincent [⬀] Manns, Fabrice Parel, Jean-Marie (co-PI) [⬀] |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Mri: Acquisition and Development of Atomic Force Microscopy Technologies For Biophysical Studies @ University of Miami School of Medicine
This is a proposal to acquire an atomic force microscope (AFM) on an inverted optical microscope and to develop two AFM-related non-imaging instruments: one for measuring single-molecule force spectroscopy and inter-molecular forces; the other, for measuring elasticities of soft samples under physiological conditions at the nano-scale. Over the past 10 years, atomic force microscopy (AFM) has become an increasingly important tool in biological research. It has gained popularity in biological applications because, unlike electron microscopy, it can image samples under physiological conditions, including live cells undergoing biological processes. The AFM acquires a topographical image of the sample surface by raster scanning an atomically sharp probe over the sample. In addition to its different imaging modes, the AFM is a versatile instrument that can be applied as a nano-indenter and as a molecular force apparatus to probe the mechanical properties of the sample. As a nano-indenter, the AFM has provided direct measurements of the local viscoelastic properties of samples on the nanometer scale. As a molecular force apparatus, the AFM has been used to measure the unbinding force of individual ligand-receptor complexes and the unfolding of individual proteins. Another attractive feature of the AFM is that it can be readily combined with optical microscopy techniques such as FRET, FRAP, TIRF and confocal microscopy. By integrating optical microscopy and AFM into a single experimental platform, the optical image can be directly correlated with the AFM data, providing a powerful tool for studying biological process in situ and in real time.
The acquisition and development of these three instruments is the first step toward establishing an ultramicroscopy center at the university. The two instruments to be developed can be constructed very economically, based on the designs of existing AFMs from the principal investigator's laboratory; this will permit the commercial AFM to be dedicated to imaging applications. The commercial AFM will be the first imaging AFM in the South Florida area and will provide a much needed resource for the local research community. These instruments will provide valuable research opportunities for undergraduates and students from underrepresented groups as well as researchers from different disciplines within the university.
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1 |
2012 — 2016 |
Manns, Fabrice |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Optics of the Growing Crystalline Lens @ University of Miami School of Medicine
DESCRIPTION (provided by applicant): The objective of this project, submitted in response to PA-10-009, Bioengineering Research Grants, is to understand how the continuous growth of the crystalline lens throughout the life span contributes to changes in the optical quality of the eye. The main hypotheses to be tested are: (1) Changes in the lens refractive index gradient due to the lens fiber cell compaction that occurs with lens growth are correlated with age-related changes in lens power and spherical aberration. (2) These changes account for the progressive loss of balance between corneal and internal ocular aberrations. The proposal has three specific Aims: Aim 1: To develop an age-dependent optical model of the crystalline lens with refractive index gradient New experimental methods will be developed to measure the refractive index gradient, refractive power and aberrations of the in vitro lens using optical coherence tomography. Once validated, these techniques will be used to quantify the optical parameters of the in vitro lens as a function of age. The data will be used to develop theoretical models and computational tools to model the changes in refractive index gradient due to lens growth and predict how these changes modify the power and aberrations of the crystalline lens. Aim 2: To quantify the contribution of the lens shape and refractive index gradient to ocular spherical aberration in vivo. The methods of Aim 1 will be extended to retrieve the in vivo lens index gradient, power, and spherical aberration from optical coherence tomography images of the anterior segment. The optical parameters of the in vivo human lens will be measured as a function of age to determine the role of lens growth on the spherical aberration of the lens and the balance between corneal and internal aberrations. Aim 3: To evaluate the contribution of the lens shape and refractive index gradient to the peripheral optics of the eye. We will apply our model by evaluating the contribution of the crystalline lens to the peripheral optical performance of the eye. The model lens will then be integrated into a whole eye model that will output the peripheral refraction and off-axis aberration in the relaxed and accommodated states, as a function of age. The data will be used to test the prediction that lens growth and accommodative changes produce changes in the peripheral refraction and off axis aberrations of the whole eye. The project will have a broad impact on the field of physiological optics at a fundamental level. Quantifying how lens power and aberrations change with age will help better understand refractive error and aberration development. By characterizing the contribution of lens growth to the ocular aberration state, the results will also help better predict the long-term outcome of aberration-guided vision correction procedures, and help design improved treatments that take into account age-changes in the lens to improve the long-term visual outcome.
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1 |
2013 — 2019 |
Manns, Fabrice |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Optomechanical Characteristics of Lens Accommodation @ University of Miami School of Medicine
DESCRIPTION (provided by applicant): The goal of this continuation project, submitted in response to PA-10-009 (Bioengineering Research Grants), is to develop new technology and to generate new knowledge that will accelerate the development of implants and surgical approaches to treat presbyopia. The project addresses two critical barriers: a) the need for instruments and techniques that measure the accommodative response and are suitable for clinical and objective evaluation of techniques to restore accommodation and b) the need to advance our understanding of the causes of presbyopia and discover the most effective strategies for restoration of accommodation. The project has three specific aims: Aim 1: To develop technology to simultaneously quantify the optical and mechanical in vivo accommodative response of the human eye. Optical coherence tomography systems, a dynamic aberrometer, an accommodation stimulus, and image processing software will be developed and integrated into a combined imaging and biometry system that will allow simultaneous measurement of the axial eye length, lens shape, lens internal structure, ciliary muscle geometry, and ocular refraction and aberrations in response to monocular accommodative stimuli. Aim 2: To characterize the age-dependence of the optical and anatomical changes in the lens and ciliary muscle with accommodation. The system developed in Aim 1 will be used to characterize the age-dependence of the accommodation-induced dynamic changes in outer and nuclear lens curvature; lens thickness and power; nuclear thickness and power; and ciliary muscle geometry. Data will be acquired on 200 human subjects from age 16 to 66. The results will be used to quantify the contribution of the lens and ciliary muscle to the loss of accommodation with age. Aim 3: To compare the pseudophakic accommodative response in subjects implanted with standard and accommodating intraocular lenses. The system developed in Aim 1 will be used to measure and compare the accommodation-induced changes in ciliary muscle geometry, intraocular lens position and ocular refraction in subjects implanted with standard monofocal intraocular lenses and subjects implanted with accommodating intraocular lenses. The results will be used to identify the parameters that govern near visual function in subjects with intraocular lenses. The project will have a broad impact on the field of presbyopia research. It will produce new technology to quantify the ocular accommodative response and evaluate the efficacy of procedures to restore accommodation. It will generate new knowledge on the causes of presbyopia and identify parameters that govern near-visual function in eyes with intraocular lenses. The knowledge gained will form a sound physiological basis for the development and optimization of new procedures and implants designed to restore accommodation.
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1 |
2021 |
Larin, Kirill V [⬀] Manns, Fabrice Scarcelli, Giuliano (co-PI) [⬀] |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Biomechanics of Accommodation
PROJECT ABSTRACT Presbyopia, the progressive age-related loss of near visual function, is associated with a stiffening of the crystalline lens. There are currently several investigational approaches for presbyopia treatment that rely on lens softening or lens replacement with softer materials. Lens softening approaches are expected to have a transformative impact on the field because they are non-invasive and they preserve the anatomical relationship between the lens and other tissues involved in accommodation. They have therefore the potential to restore the natural dynamic accommodative function. However, one of the fundamental roadblocks towards the development of lens softening procedures is that there is currently no method available to directly measure lens stiffness and thus assess the efficacy of lens softening procedures in vivo. The goal of the project is to develop new technology capable of precise spatially-resolved non-destructive, noninvasive and depth-resolved quantitative measurements of the lens mechanical properties in a clinical setting. The technology will combine Brillouin microscopy, Optical Coherence Tomography (OCT), and Optical Coherence Elastography (OCE) - BOE. The instrument will be used to generate the first age-dependent data on lens mechanical properties quantified in vivo as well as quantitatively assess therapeutic procedures aimed to restore accommodation. Our overall hypothesis is that the novel BOE technology can acquire absolute measurements of the lens stiffness gradient with the accuracy and precision required to detect both age-related changes and changes induced by lens softening treatments. The ability to quantify lens softening in vivo will have a major impact on pre-clinical and clinical testing, validation and optimization of lens softening procedures. The project has three specific aims: Aim 1: Develop a combined BOE imaging device for depth-resolved quantitative lens elastography. Aim 2: Validate BOE measurements in animal and human lens ex vivo and animal lens in vivo. Aim 3: Quantify the mechanical properties of the human lens in vivo To accomplish our objective, we have assembled a multidisciplinary team with expertise in optical coherence tomography and elastography (Larin), Brillouin technology (Scarcelli), biomechanical modeling (Aglyamov), clinical ophthalmic instrumentation and crystalline lens physiology (Manns, Parel, Ruggeri, Yoo).
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0.972 |