Dataset Information

In-Situ Optical Coherence Tomography (OCT) for the Time-Resolved Investigation of Crystallization Processes in Polymers.

ABSTRACT: By application of optical coherence tomography (OCT), an interferometric noncontact imaging technique, the crystallization of a supercooled poly(propylene) melt in a slit die is monitored. Both the quiescent and the sheared melt are investigated, with a focus on experiments where solidification and flow occur simultaneously. OCT is found to be an excellent tool for that purpose since the resultant structures are strongly scattering, which is a prerequisite for application of that method. The resulting images enable for the first time to directly monitor structure development throughout the whole experiment, including final cooling to room temperature. By rendering the setup polarization-sensitive, information on the birefringence of the pertinent structures is obtained.

SUBMITTER: Hierzenberger P

PROVIDER: S-EPMC3966339 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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In-Situ Optical Coherence Tomography (OCT) for the Time-Resolved Investigation of Crystallization Processes in Polymers.

Hierzenberger Peter P Leiss-Holzinger Elisabeth E Heise Bettina B Stifter David D Eder Gerhard G

Macromolecules 20140314 6

By application of optical coherence tomography (OCT), an interferometric noncontact imaging technique, the crystallization of a supercooled poly(propylene) melt in a slit die is monitored. Both the quiescent and the sheared melt are investigated, with a focus on experiments where solidification and flow occur simultaneously. OCT is found to be an excellent tool for that purpose since the resultant structures are strongly scattering, which is a prerequisite for application of that method. The res ...[more]

PMID: 24683273

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Project description:ObjectiveThis study aims to evaluate the feasibility of retinal imaging in critical care using a novel mobile optical coherence tomography (OCT) device. The Heidelberg SPECTRALIS FLEX module (Heidelberg Engineering, Heidelberg, Germany) is an OCT unit with a boom arm, enabling ocular OCT assessment in less mobile patients.DesignWe undertook an evaluation of the feasibility of using the SPECTRALIS FLEX for undertaking ocular OCT images in unconscious and critically ill patients.SettingThis study was conducted in the critical care unit of a large tertiary referral unit in the United Kingdom.Participants13 systemically unwell patients admitted to the critical care unit were purposively sampled to enable evaluation in patients with a range of clinical states.Outcome measuresThe primary outcome was the feasibility of acquiring clinically interpretable OCT scans on a consecutive series of patients. The standardised scanning protocol included macula-focused OCT, OCT optic nerve head (ONH), OCT angiography (OCTA) of the macula and ONH OCTA.ResultsOCT images from 13 patients were attempted. The success rates of each scan type are 84% for OCT macula, 76% for OCT ONH, 56% for OCTA macula and 36% for OCTA ONH. The overall mean success rate of scans per patient was 64% (95% CI 46% to 81%). Clinicians reported clinical value in 100% scans which were successfully obtained, including both ruling in and ruling out relevant ocular complications such as corneal thinning, macular oedema and optic disc swelling. The most common causes of failure to achieve clinically interpretable scans were inadequately sustained OCT alignment in delirious patients and a compromised ocular surface due to corneal exposure.ConclusionsThis prospective evaluation indicates the feasibility and potential clinical value of the SPECTRALIS FLEX OCT system on the critical care unit. Portable OCT systems have the potential to bring instrument-based ophthalmic assessment to critically ill patients, enabling detection and micron-level monitoring of ocular complications.

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Dataset Information

In-Situ Optical Coherence Tomography (OCT) for the Time-Resolved Investigation of Crystallization Processes in Polymers.

Publications

In-Situ Optical Coherence Tomography (OCT) for the Time-Resolved Investigation of Crystallization Processes in Polymers.

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