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dc.identifier.urihttp://hdl.handle.net/11401/76968
dc.description.sponsorshipThis work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.en_US
dc.formatMonograph
dc.format.mediumElectronic Resourceen_US
dc.language.isoen_US
dc.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dc.typeDissertation
dcterms.abstractSpinal cord ischemia, caused by a prolonged loss of blood flow to the spinal cord, can occur as a result of direct trauma to the spinal cord or as a complication of major vascular, spine and spinal cord surgery, and surgeries for the stabilization of spinal cord trauma, often resulting in partial or complete paresis/paralysis. Current electrophysiological methods employed to detect spinal cord ischemia, namely somatosensory and motor evoked potentials, are indirect, temporally insensitive, nonspecific, and cumbersome. There is no technology currently available that can directly and immediately detect the onset of spinal cord ischemia, nor provide immediate feedback on the efficacy of interventions aimed at ameliorating spinal ischemia by improving flow and oxygen delivery. The goal of this dissertation involves the development of a prototypical optical device, based on the principles of Diffuse Correlation Spectroscopy (DCS) and Diffuse Optical Spectroscopy (DOS), that would allow for the immediate detection and continuous monitoring of changes in spinal cord blood flow and oxygenation and testing it in a sheep model. DCS and DOS are diffuse optical techniques that utilize near-infrared light to continuously measure changes in blood flow and oxyhemoglobin/ deoxyhemoglobin concentrations respectively. A thin, flexible fiber optic probe was designed to enable minimally invasive percutaneous placement on to the sheep spinal cord. A series of proof-of-concept experiments tested and proved the hypothesis that the optical device would indeed detect changes in spinal cord blood flow and oxygenation, induced both pharmacologically and mechanically. Since DCS is a relatively novel technique, the blood flow changes detected by DCS were correlated with changes detected by an established method of blood flow measurement, isotope-labeled microspheres and a relatively good correlation was observed. The safety associated with the fiber optic probe, in terms of placement and laser heating, was evaluated through neurological monitoring of the sheep and histological assessment of spinal cord tissue. The hypothesis that the optical device could detect spinal cord ischemia earlier than evoked potential monitoring was tested by simultaneously comparing the time taken by the two technologies to detect a loss in blood flow upon aortic occlusion. This monitoring tool potentially represents an important step forward, offering a new level of accuracy and immediacy that could assist surgeons in pre-surgical planning, in intraoperative detection of spinal cord ischemia, and in postoperative monitoring in the cardiothoracic and neurological critical care settings.
dcterms.available2017-09-20T16:51:33Z
dcterms.contributorPan, Yingtianen_US
dcterms.contributorFloyd, Thomas Fen_US
dcterms.contributorLin, Weien_US
dcterms.contributorYodh, Arjun.en_US
dcterms.creatorKogler, Angela Sofia
dcterms.dateAccepted2017-09-20T16:51:33Z
dcterms.dateSubmitted2017-09-20T16:51:33Z
dcterms.descriptionDepartment of Biomedical Engineeringen_US
dcterms.extent171 pg.en_US
dcterms.formatMonograph
dcterms.formatApplication/PDFen_US
dcterms.identifierhttp://hdl.handle.net/11401/76968
dcterms.issued2016-12-01
dcterms.languageen_US
dcterms.provenanceMade available in DSpace on 2017-09-20T16:51:33Z (GMT). No. of bitstreams: 1 Kogler_grad.sunysb_0771E_12864.pdf: 27724277 bytes, checksum: e17c0d5b25e79b5093f1af7996fd8d8d (MD5) Previous issue date: 1en
dcterms.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dcterms.subjectBiomedical engineering
dcterms.titleDiffuse Correlation and Optical Spectroscopies for the Monitoring of Spinal Cord Hemodynamics
dcterms.typeDissertation


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