Imaging the Mucosa of the Human Vocal Fold with Optical Coherence Tomography

Objectives: Discerning the layered microstructure of the vocal folds is critical for effective phonomicrosurgery. Optical coherence tomography (OCT), a noncontact, noninvasive technology that provides cross-sectional images by means of backscattered light, offers the potential for delineating these layers in vivo. Methods: The glottal mucosa of 3 human cadaver larynges was imaged with conventional OCT and polarization-sensitive OCT (PS-OCT). Images were obtained through the epithelium and lamina propria. Results: Although the superficial layer of the lamina propria appeared quite homogeneous, the outer surface of the superficial lamina propria was correlated with an increase in backscatter with OCT. The superficial lamina propria and vocal ligament were correlated with a marked increase in tissue birefringence with PS-OCT. Conclusions: This preliminary study demonstrates the capacity of OCT and PS-OCT for visualizing the layered microstructure of the vocal fold mucosa. We believe that these imaging techniques will have applications in the exploration of solutions to vocal fold scarring and in imaging vocal fold disorders in the clinic and operating room.

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Modern Trends in Imaging V: Optical Coherence Tomography for Rapid Tissue Screening and Directed Histological Sectioning

Analytical Cellular Pathology ◽

10.1155/2012/757236 ◽

2012 ◽

Vol 35 (3) ◽

pp. 129-143 ◽

Cited By ~ 11

Author(s):

Woonggyu Jung ◽

Stephen A. Boppart

Keyword(s):

Optical Coherence Tomography ◽

Real Time ◽

Image Guidance ◽

Diagnostic Yield ◽

Imaging Modality ◽

Imaging Techniques ◽

Optical Coherence ◽

Sampling Errors ◽

Cross Sectional

In pathology, histological examination of the “gold standard” to diagnose various diseases. It has contributed significantly toward identifying the abnormalities in tissues and cells, but has inherent drawbacks when used for fast and accurate diagnosis. These limitations include the lack ofin vivoobservation in real time and sampling errors due to limited number and area coverage of tissue sections. Its diagnostic yield also varies depending on the ability of the physician and the effectiveness of any image guidance technique that may be used for tissue screening during excisional biopsy. In order to overcome these current limitations of histology-based diagnostics, there are significant needs for either complementary or alternative imaging techniques which perform non-destructive, high resolution, and rapid tissue screening. Optical coherence tomography (OCT) is an emerging imaging modality which allows real-time cross-sectional imaging with high resolutions that approach those of histology. OCT could be a very promising technique which has the potential to be used as an adjunct to histological tissue observation when it is not practical to take specimens for histological processing, when large areas of tissue need investigating, or when rapid microscopic imaging is needed. This review will describe the use of OCT as an image guidance tool for fast tissue screening and directed histological tissue sectioning in pathology.

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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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Reinke's Edema: Phonatory Mechanisms and Management Strategies

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949710600701 ◽

1997 ◽

Vol 106 (7) ◽

pp. 533-543 ◽

Cited By ~ 68

Author(s):

Steven M. Zeitels ◽

Glenn W. Bunting ◽

Robert E. Hillman ◽

Traci Vaughn

Keyword(s):

Lamina Propria ◽

Fundamental Frequency ◽

Vocal Fold ◽

Management Strategies ◽

Vocal Folds ◽

Vocal Fold Vibration ◽

Reinke’S Edema ◽

Subglottal Pressure ◽

Almost All ◽

Superficial Lamina

Reinke's edema (RE) has been associated typically with smoking and sometimes with vocal abuse, but aspects of the pathophysiology of RE remain unclear. To gain new insights into phonatory mechanisms associated with RE pathophysiology, weused an integrated battery of objective vocal function tests to analyze 20 patients (19 women) who underwent phonomicrosurgical resection. Preoperative stroboscopic examinations demonstrated that the superficial lamina propria is distended primarily on the superior vocal fold surface. Acoustically, these individuals have an abnormally low average speaking fundamental frequency (123 Hz), and they generate abnormally high average subglottal pressures (9.7 cm H20). The presence of elevated aerodynamic driving pressures reflects difficulties in producing vocal fold vibration that are most likely the result of mass loading associated with RE, and possibly vocal hyperfunction. Furthermore, it is hypothesized that in the environment of chronic glottal mucositis secondary to smoking and reflux, the cephalad force on the vocal folds by the subglottal driving pressure contributes to the superior distention of the superficial lamina propria. Surgical reduction of the volume of the superficial lamina propria resulted in a significant elevation in fundamental frequency (154 Hz) and improvement in perturbation measures. In almost all instances, both the clinician and the patient perceived the voice as improved. However, these patients continued to generate elevated subglottal pressure (probably a sign of persistent hyperfunction) that was accompanied by visually observed supraglottal strain despite the normalsized vocal folds. This finding suggests that persistent hyperfunctional vocal behaviors may contribute to postsurgical RE recurrence if therapeutic strategies are not instituted to modify such behavior.

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Optical coherence tomography of the pancreatic and bile ducts: are we ready for prime time?

Endoscopy International Open ◽

10.1055/a-1119-6248 ◽

2020 ◽

Vol 08 (05) ◽

pp. E644-E649

Author(s):

Amy Tyberg ◽

Isaac Raijman ◽

Aleksey A. Novikov ◽

Divyesh V. Sejpal ◽

Petros C. Benias ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Pancreatic Duct ◽

Imaging System ◽

Biliary Duct ◽

Optical Coherence ◽

Cross Sectional ◽

Reflective Surface ◽

Cross Sectional Imaging ◽

Sectional Imaging

Abstract Background and study aims First-generation optical coherence tomography (OCT) has been shown to increase diagnostic sensitivity for malignant biliary and pancreatic-duct strictures. A newer OCT imaging system, NVision Volumetric Laser Endomicroscopy (VLE), allows for in vivo cross-sectional imaging of the ductal wall at the microstructure level during endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to identify and evaluate characteristics on OCT that are predictive of benign and malignant strictures. Patients and methods Consecutive patients from six centers who underwent OCT between September 2016 and September 2017 were included in a dedicated registry. OCT images were analyzed, and nine recurring characteristics were further assessed. Final diagnosis was based on histology and/or surgical pathology. Results 86 patients were included (49 % male, mean age 64.7). OCT was performed in the bile duct in 79 patients and the pancreatic duct in seven. Nine OCT characteristics were identified: dilated hypo-reflective structures (n = 7), onion-skin layering (n = 8), intact layering (n = 17), layering effacement (n = 25), scalloping (n = 20), thickened epithelium (n = 42), hyper-glandular mucosa (n = 13), prominent blood vessels (n = 6), and a hyper-reflective surface (n = 20). Presence of hyper-glandular mucosa, hyper-reflective surface and scalloping significantly increased the odds of malignancy diagnosis by 6 times more (P = 0.0203; 95 % CI 1.3 to 26.5), 4.7 times more (P = 0.0255; 95 % CI 1.2 to 18.0) and 7.9 times more (P = 0.0035; 95 % CI 1.97 to 31.8) respectively. Conclusion By providing in-vivo cross-sectional imaging of the pancreatic and biliary duct wall, OCT technology may improve sensitivity in diagnosing malignant strictures and provide standardizable criteria predictive of malignancy.

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In vivo 3D human vocal fold imaging with polarization sensitive optical coherence tomography and a MEMS scanning catheter

Optics Express ◽

10.1364/oe.18.014644 ◽

2010 ◽

Vol 18 (14) ◽

pp. 14644 ◽

Cited By ~ 32

Author(s):

Ki Hean Kim ◽

James A. Burns ◽

Jonathan J. Bernstein ◽

Gopi N. Maguluri ◽

B. Hyle Park ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Vocal Fold ◽

Optical Coherence

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Role of Optical Coherence Tomography on Corneal Surface Laser Ablation

Journal of Ophthalmology ◽

10.1155/2012/676740 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Bruna V. Ventura ◽

Haroldo V. Moraes ◽

Newton Kara-Junior ◽

Marcony R. Santhiago

Keyword(s):

Optical Coherence Tomography ◽

Laser Ablation ◽

Imaging Modality ◽

Corneal Thickness ◽

Optical Coherence ◽

Corneal Surface ◽

Cross Sectional ◽

Surface Laser ◽

The Time Domain

This paper focuses on reviewing the roles of optical coherence tomography (OCT) on corneal surface laser ablation procedures. OCT is an optical imaging modality that uses low-coherence interferometry to provide noninvasive cross-sectional imaging of tissue microstructurein vivo.There are two types of OCTs, each with transverse and axial spatial resolutions of a few micrometers: the time-domain and the fourier-domain OCTs. Both have been increasingly used by refractive surgeons and have specific advantages. Which of the current imaging instruments is a better choice depends on the specific application. In laserin situkeratomileusis (LASIK) and in excimer laser phototherapeutic keratectomy (PTK), OCT can be used to assess corneal characteristics and guide treatment decisions. OCT accurately measures central corneal thickness, evaluates the regularity of LASIK flaps, and quantifies flap and residual stromal bed thickness. When evaluating the ablation depth accuracy by subtracting preoperative from postoperative measurements, OCT pachymetry correlates well with laser ablation settings. In addition, OCT can be used to provide precise information on the morphology and depth of corneal pathologic abnormalities, such as corneal degenerations, dystrophies, and opacities, correlating with histopathologic findings.

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Measurement of Vibrating Tympanic Membrane in an In Vivo Mouse Model Using Doppler Optical Coherence Tomography

Journal of Imaging ◽

10.3390/jimaging5090074 ◽

2019 ◽

Vol 5 (9) ◽

pp. 74

Author(s):

Jeon ◽

Kim ◽

Jeon ◽

Kim

Keyword(s):

Optical Coherence Tomography ◽

Phase Shift ◽

Tympanic Membrane ◽

Middle Ear ◽

Acoustic Stimulus ◽

Optical Coherence ◽

Cross Sectional ◽

Vibratory Motion ◽

Doppler Optical Coherence Tomography

Optical coherence tomography (OCT) has a micro-resolution with a penetration depth of about 2 mm and field of view of about 10 mm. This makes OCT well suited for analyzing the anatomical and internal structural assessment of the middle ear. To study the vibratory motion of the tympanic membrane (TM) and its internal structure, we developed a phase-resolved Doppler OCT system using Kasai’s autocorrelation algorithm. Doppler optical coherence tomography is a powerful imaging tool which can offer the micro-vibratory measurement of the tympanic membrane and obtain the micrometer-resolved cross-sectional images of the sample in real-time. To observe the relative vibratory motion of individual sections (malleus, thick regions, and the thin regions of the tympanic membrane) of the tympanic membrane in respect to auditory signals, we designed an experimental study for measuring the difference in Doppler phase shift for frequencies varying from 1 to 8 kHz which were given as external stimuli to the middle ear of a small animal model. Malleus is the very first interconnecting region between the TM and cochlea. In our proposed study, we observed that the maximum change in Doppler phase shift was seen for the 4 kHz acoustic stimulus in the malleus, the thick regions, and in the thin regions of the tympanic membrane. In particular, the vibration signals were higher in the malleus in comparison to the tympanic membrane.

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