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Ocular Imaging (ocular + imaging)
Selected Abstracts7 Tesla MR imaging of the human eye in vivoJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2009Kathryn Richdale OD Abstract Purpose: To develop a protocol which optimizes contrast, resolution and scan time for three-dimensional (3D) imaging of the human eye in vivo using a 7 Tesla (T) scanner and custom radio frequency (RF) coil. Materials and Methods: Initial testing was conducted to reduce motion and susceptibility artifacts. Three-dimensional FFE and IR-TFE images were obtained with variable flip angles and TI times. T1 measurements were made and numerical simulations were performed to determine the ideal contrast of certain ocular structures. Studies were performed to optimize resolution and signal-to-noise ratio (SNR) with scan times from 20 s to 5 min. Results: Motion and susceptibility artifacts were reduced through careful subject preparation. T1 values of the ocular structures are in line with previous work at 1.5T. A voxel size of 0.15 × 0.25 × 1.0 mm3 was obtained with a scan time of approximately 35 s for both 3D FFE and IR-TFE sequences. Multiple images were registered in 3D to produce final SNRs over 40. Conclusion: Optimization of pulse sequences and avoidance of susceptibility and motion artifacts led to high quality images with spatial resolution and SNR exceeding prior work. Ocular imaging at 7T with a dedicated coil improves the ability to make measurements of the fine structures of the eye. J. Magn. Reson. Imaging 2009;30:924,932. © 2009 Wiley-Liss, Inc. [source] Laser applications and system considerations in ocular imagingLASER & PHOTONICS REVIEWS, Issue 5 2008A.E. Elsner Abstract We review laser applications for primarily in-vivo ocular imaging techniques, describing their constraints based on biological tissue properties, safety, and the performance of the imaging system. We discuss the need for cost-effective sources with practical wavelength-tuning capabilities for spectral studies. Techniques to probe the pathological changes of layers beneath the highly scattering retina and diagnose the onset of various eye diseases are described. The recent development of several optical-coherence-tomography-based systems for functional ocular imaging is reviewed, as well as linear and nonlinear ocular-imaging techniques performed with ultrafast lasers, emphasizing recent source developments and methods to enhance imaging contrast. [source] The role of contemporary ocular imaging in neuro-ophthalmologyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2009Peter Savino MD No abstract is available for this article. [source] | ||||||||||