High speed rotary system for catheter based 3-D imaging with optical coherence tomography (OCT)

10.32920/ryerson.14652363 ◽

2021 ◽

Author(s):

Antonio Mauro

Keyword(s):

Optical Coherence Tomography ◽

High Speed ◽

Imaging Techniques ◽

Three Dimensional ◽

Biological Tissues ◽

Optical Coherence ◽

X Rays ◽

Sound Waves ◽

Acquisition Rate

Optical Coherence Tomography (OCT) is an addition to the other tomographic imaging techniques of x-ray computed tomography, magnetic resonance imaging, and ultrasound imaging. OCT uses optical reflections of biological tissues as opposed to x-rays, RF fields, and sound waves to obtain images. A rotary and pullback system has been developed for use with OCT. The system was developed to facilitate the three dimensional imaging of various lumens in humans and animals. The system is capable of rotating at a rate of 200 Hz. At this rate the rotary system will allow for a frame acquisition rate of 200 fps which is significantly higher than the highest published acquisition rate to date of 108 fps. The probes used with the system were modeled after the Intravascular Ultrasound (IVUS) miniature torque cable design. The probes can be sealed and sterilized between subjects without being damaged; unlike the single use IVUS probes. The rotary system was used to image the outer ear of a mouse in vivo. A lateral slice from the resulting three dimensional image was compared to the general histology of a mouse ear. The image compared well to the general anatomy as found on the histology.

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Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽

10.3390/s21134554 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4554

Author(s):

Ralph-Alexandru Erdelyi ◽

Virgil-Florin Duma ◽

Cosmin Sinescu ◽

George Mihai Dobre ◽

Adrian Bradu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Radiation Dose ◽

Imaging Techniques ◽

Image Resolution ◽

Optical Coherence ◽

X Rays ◽

High Quality ◽

X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

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Three-dimensional measurement by high-speed line-field Fourier-domain optical coherence tomography in vivo

10.1117/12.648332 ◽

2006 ◽

Author(s):

Shuichi Makita ◽

Yosifumi Nakamura ◽

Yoshiaki Yasuno ◽

Takashi Endo ◽

Masahiro Yamanari ◽

...

Keyword(s):

Optical Coherence Tomography ◽

High Speed ◽

Three Dimensional ◽

Fourier Domain ◽

Optical Coherence ◽

Line Field ◽

Dimensional Measurement ◽

Three Dimensional Measurement

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Towards high speed high sensitivity optical coherence tomography for in vivo functional imaging

10.32469/10355/47077 ◽

2015 ◽

Author(s):

◽

Miao Zhang

Keyword(s):

Optical Coherence Tomography ◽

High Speed ◽

Imaging System ◽

Biological Tissues ◽

Dual Band ◽

Optical Coherence ◽

Process Data ◽

Airy Beam ◽

Imaging Speed

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Optical coherence tomography (OCT) is an imaging technique that has been widely used in clinics and industrial fields. This dissertation, making use of several emerging techniques, works on improving the imaging speed and sensitivity of current OCT systems so that it will be more powerful in imaging biological tissues, live animals and human patients. Dual-band Fourier domain OCT (FD-OCT) has the potential to provide high quality images that can differentiate different types of tissues. However, previous dual-band FD-OCT systems could not give correct information due to inherited limitations in imaging system setup, sample properties and theory. Our new imaging system overcomes these limitations by using unique hardware and software design. In our imaging system, different false signals are suppressed and the signal attenuation due to samples are compensated using proposed algorithms that derived from theoretical analysis. A video card is used to process data in an ultrahigh speed. With high imaging speed we are able to imaging live animals despite the movement of subjects. The high speed also makes it possible to display the imaging volume interactively in 3D. The image quality and information contained in the images are improved. We further developed an OCT imaging system using a special kind of optical beam called finite energy Airy beam. Compared to OCT system using traditional optical beams, Airy beam OCT has the potential to view a much longer range and view deeper inside the biological tissue.

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Optical Coherence Tomography for Three-Dimensional Imaging in the Biomedical Field: A Review

Frontiers in Physics ◽

10.3389/fphy.2021.744346 ◽

2021 ◽

Vol 9 ◽

Author(s):

Shu Zheng ◽

Yanru Bai ◽

Zihao Xu ◽

Pengfei Liu ◽

Guangjian Ni

Keyword(s):

Optical Coherence Tomography ◽

High Speed ◽

Near Infrared ◽

Polarization State ◽

Three Dimensional ◽

Biological Research ◽

Light Sources ◽

Optical Coherence ◽

Biomedical Field

Optical coherence tomography (OCT) has become a novel approach to noninvasive imaging in the past three decades, bringing a significant potential to biological research and medical biopsy in situ, particularly in three-dimensional (3D) in vivo conditions. Specifically, OCT systems using broad bandwidth sources, mainly centered at near-infrared-II, allow significantly higher imaging depth, as well as maintain a high-resolution and better signal-to-noise ratio than the traditional microscope, which avoids the scattering blur and thus obtains more details from delicate biological structures not just limited to the surface. Furthermore, OCT systems combined the spectrometer with novel light sources, such as multiplexed superluminescent diodes or ultra-broadband supercontinuum laser sources, to obtain sub-micron resolution imaging with high-speed achieve widespread clinical applications. Besides improving OCT performance, the functional extensions of OCT with other designs and instrumentations, taking polarization state or birefringence into account, have further improved OCT properties and functions. We summarized the conventional principle of OCT systems, including time-domain OCT, Fourier-domain OCT, and several typical OCT extensions, compared their different components and properties, and analyzed factors that affect OCT performance. We also reviewed current applications of OCT in the biomedical field, especially in hearing science, discussed existing limitations and challenges, and looked forward to future development, which may provide a guideline for those with 3D in vivo imaging desires.

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Three-dimensional optical coherence tomography of the human retina in vivo by high-speed transversal scanning

10.1117/12.527722 ◽

2004 ◽

Cited By ~ 2

Author(s):

Christoph K. Hitzenberger ◽

Peter Trost ◽

Pak-Wai Lo ◽

Qienyuan Zhou

Keyword(s):

Optical Coherence Tomography ◽

High Speed ◽

Three Dimensional ◽

Human Retina ◽

Optical Coherence

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Dental Diagnosis and Treatment Assessments: Between X-rays Radiography and Optical Coherence Tomography

Materials ◽

10.3390/ma13214825 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4825

Author(s):

Ralph-Alexandru Erdelyi ◽

Virgil-Florin Duma ◽

Cosmin Sinescu ◽

George Mihai Dobre ◽

Adrian Bradu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Imaging Techniques ◽

Correct Diagnosis ◽

Three Dimensional ◽

Daily Basis ◽

Image Resolution ◽

Imaging Method ◽

Optical Coherence ◽

X Rays ◽

Swept Source

A correct diagnosis in dental medicine is typically provided only after clinical and radiological evaluations. They are also required for treatment assessments. The aim of this study is to establish the boundaries from which a modern, although established, imaging technique, Optical Coherence Tomography (OCT), is more suitable than the common X-ray radiography to assess dental issues and treatments. The most common methods for daily-basis clinical imaging are utilized in this study for extracted teeth (but also for other dental samples and materials), i.e., panoramic, intraoral radiography, and three-dimensional (3D) cone beam computed tomography (CBCT). The advantages of using OCT as an imaging method in dentistry are discussed, with a focus on its superior image resolution. Drawbacks related to its limited penetration depth and Field-of-View (FOV) are pointed out. High-quality radiological investigations are performed, measurements are done, and data collected. The same teeth and samples are also imaged (mostly) with an in-house developed Swept Source (SS)-OCT system, Master-Slave enhanced. Some of the OCT investigations employed two other in-house developed OCT systems, Spectral Domain (SD) and Time Domain (TD). Dedicated toolbars from Romexis software (Planmeca, Helsinki, Finland) are used to perform measurements using both radiography and OCT. Clinical conclusions are drawn from the investigations. Upsides and downsides of the two medical imaging techniques are concluded for each type of considered diagnosis. For treatment assessments, it is concluded that OCT is more appropriate than radiography in all applications, except bone-related investigations and periodontitis that demand data from higher-penetration depths than possible with the current level of OCT technology.

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