Yasuno became associate editor of Optics Express

Our colleague Yoshiaki Yasuno became an associate editor of Optics Express. Optics Express is organized by Optical Society of America, and is one of the highest impact journals in the field of optics. Yasuno edits papers mainly of biomedical optics.

Generalized Jones Matrix OCT

Shuichi Makita and his colleagues in COG recently reported the generalization of Jones matrix optical coherence tomography (Jones OCT) in Optics Express. In this paper, we generalized theoretical model of Jones OCT which provides us not only phase retardation tomography but local birefringence tomography of biological and medical samples. The noise property of this generalized Jones OCT is also carefully analyzed. This method was applied to visualize the details of an anterior eye chamber, and successfully contrast a trabecular meshwork. The details are described in the following paper.

>> Full text (PDF) in Journal web site (open access)

Citation: S. Makita, M. Yamanari, and Y. Yasuno, "Generalized Jones matrix optical coherence tomography: performance and local birefringence imaging," Opt. Express 18, 854-876 (2010).

doi:10.1364/OE.18.000954

Investigation of Choroidal Thickness

Our collaborator Yasushi Ikuno (Osaka University Hospital) investigated the choroidal thickness of healthy Japanese. The chorid is one of the tissues in the eye ant it locates beneath the retina, and which had not been possible to be clearly visualized by OCT. He investigated the choroid by using a brand new high-penetration OCT made by our group (COG, Tsukuba). After the examination of 86 eyes, he found that the choroidal thickness varies around its position, and is associated the refractive error of the eye, axial eye length, and the age of the subject. The details are reported in Investigative Ophthalmology and Visual Science (IOVS, a journal of association for research in vision and ophthalmology).

>> Abstract in journal website

>> Request reprint via e-mail (please indicate the following citation in the e-mail).

Citation: Y. Ikuno, K. Kawaguchi, T. Nouchi, and Y. Yasuno, "Choroidal thickness in healthy Japanese Subjects," Invest. Ophthalmol. Vis. Sci., e-first publication.
doi:10.1167/iovs.09-4383

Birefringence Imaging of Necrotizing Scleritis

Our colleagues Masahiro Miura published a case report of necrotizing scleritis, which is an inflammation disease of sclera. The anterior eye of a patient was scanned by our anterior eye segment polarization sensitive optical coherence tomography prototype (AS-PS-OCT). The tissue selective imaging ability of AS-PS-OCT visualized the abnormal thinning of the eye. The details were published in Ophthalmic Surgery, Lasers and Imaging.

>> Abstract (PubMed)

>> Request reprint via e-mail (please indicate the following citation in the e-mail.)

Citation: M. Miura, M. Yamanari, T. Iwasaki, M. Itoh, T. Yatagai, and Y. Yasuno, "Polarization-sensitive optical coherence tomography of necrotizing scleritis," Ophthalmic Surg. Lasers Imaging 40, 607-610 (2009).

Tissue Discrimination Imaging of Anterior Eye

Our colleague Arata Miyazawa reported a new imaging methodology which used polarization sensitive optical coherence tomography (PS-OCT) and a newly developed algorithm to discriminate tissues based on their optical properties. This algorithm uses three optical properties obtained by PS-OCT including scattering intensity, signal extinction coefficient along depth, and local birefringence, and discriminates tissues based on these properties. By using this algorithm, five tissue types of an anterior eye including trabecular meshwork, conjunctiva, sclera, cornea and uvea were successfully discriminated. The details was published in Optics Express.

>> Abstract on journal web-site (Open Access)

Citation: A. Miyazawa, M. Yamanari, S. Makita, M. Miura, K. Kawana, K. Iwaya, H. Goto, and Y. Yasuno, "Tissue discrimination in anterior eye using three optical parameters obtained by polarization sensitive optical coherence tomography, " Opt. Express 17, 17426-17440 (2009).

Ocular Biometry by 3D-OCT

Our collaborator Shinichi Fukuda investigated the utility of 3D corneal and anterior eye segment optical coherence tomography (3D-CAS-OCT) for ocular biometry. The ocular biometry is a method to extract numerical parameters from an eye, which represent the functions and integrity of the eye, e.g. a central corneal thickness (CCT) or an anterior eye chamber depth (ACD).

He examined 40 eyes of 40 normal subjects by 3D-CAS-OCT, Scheimpflug camera, scanning-slit topography and ultrasonic pachymetry, and obtained CCT, ACD and other parameters. This study indicated 3D-CAS-OCT was usable for ocular biometry.

This study has been reported on a journal Ophthalmology. The paper and abstract is available on the following locations.

>> Journal web site
>> Request reprint via e-mail (please indicate the following citation in the e-mail.)

Citation: S. Fukuda, K. Kawana, Y. Yasuno and T. Oshika, "Anterior ocular biometry using 3-dimensional optical coherence tomography," Ophthalmology 116, 882-889 (2009).

3D Investigation of Glaucoma Surgery

Keisuke Kawana has reported 3D tomographic investigation of trabeculectomy blebs. The bleb is an artificial structure created on the anterior eye by a surgery "trabeculectomy" which is for the treatment of glaucoma. He employed 3D swept-source OCT for this investigation. Internal outflow channels and scleral flaps were successfully visualized.

This report has been published in Opthalmology, and available from the following links.

>> Abstract on Journal web-site

>> Request reprint via e-mail. (Please copy and past the following citation.)

Citation: K. Kawana, T. Kiuchi, Y. Yasuno and T. Oshika, "Evaluation of trabeculectomy blebs using 3-dimensional cornea and anterior segment optical coherence tomography," Ophthalmology 116, 848-855 (2009).

Publication: OCT guided surgery of cornea

Hideki Mori recently published a paper of 3D OCT guided phototherapeutic keratectomy (PTK) for the treatment of granular corneal dystrophy. In this paper, he demonstrated a simulation of laser surgery of corneal dystrophy based on 3D OCT volume. This simulation was compared to the result of real PTK surgery and they showed a good agreement.

>> Abstract on Publishers' web-sites

>> Request reprint

(via e-mail. Please indicate the citation).

Citation: H. Mori, M. Miura, T. Iwasaki, H. Goto, Y. Sakurai, Y. Watanabe and Y. Yasuno, "Three-dimensional optical coherence tomography-guided phototherapeutic keratectomy for granular corneal dystrophy, " Cornea 28, 944-947 (2009).

New Publication: Dermal Birefringence and Skin Surface

Shingo Sakai recently published a paper "Relationship Between Dermal Birefringence and the Skin Surface Roughness of Photoaged Human Skin" in Journal of Biomedical Optics. In this paper, he showed a significant correlation between the birefringence of the upper dermal region of human skin and its surface roughness. This result suggests that solar elastosis is a major factor for the progress of wrinkles.

This paper is available on the website of Journal of Biomedical Optics.

>>> Abstract and PDF on journal website

Citation: S. Sakai, N. Nakagawa, M. Yamanari, A. Miyazawa, Y. Yasuno and M. Matsumoto, "Relationship between Dermal Birefringence and the Skin Surface Roughness of Photoaged Human Skin," J. Biomed. Opt. 14, 044032 (2009).

New Publication: Segmentation of Retinal Pigment Epithelium

Tapio Fabritius recently published a paper which describes an automated and fast algorithm to segment retinal pigment epithelium (RPE) by using the intensity based OCT images. This algorithm is using an itteration loop to connect the segmented locations of RPE of each B-scan, and provide smooth en-face map of RPE position. It was also proven that this algorithm works well with pathologic cases.

This paper is freely available on Optics Express website.

>>> Abstract and PDF on Optics Express

Citation: T. Fabritius, S. Makita, M. Miura, R. Myllyla, and Y. Yasuno, "Automated segmentation of the macula by optical coherence tomography," Opt. Express 17, 15659-15669 (2009).

New publication: 1-um polarization-sensitive SS-OCT

Our new paper about 1-um polarization-sensitive SS-OCT was published in Optics Express. Phase retardation images of sclera and lamina cribrosa in the posterior eye were visualized at 1-um wavelength for the first time. We described how the system sensitivity was optimized and how the polarization-insensitive image was important for the imaging of birefringent tissues.

The paper is available with open access in Optics Express.

Citation: Masahiro Yamanari, Yiheng Lim, Shuichi Makita, and Yoshiaki Yasuno, "Visualization of phase retardation of deep posterior eye by polarization-sensitive swept-source optical coherence tomography with 1-µm probe," Opt. Express 17, 12385-12396 (2009)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-17-15-12385

SPIE Newsroom: Multifunctional Anterior OCT

An article of our multifunctional anterior optical coherence tomography is now available on SPIE newsroom. This article for general readers may give you a quick overview of cutting-edge anterior OCT!

>>> SPEI Newsroom: Multifunctional optical imaging reveals properties of the anterior eye

Joschi

Our Ophthalmologist receives PhD of Engineering

I proudly announce that our aggressive ophthalmologist Dr. Masahiro Miura received PhD of Engineering, his second PhD,s from University of Tsukuba. The subject of his PhD was ophthalmic polarimetries in ophthalmology, which includes polarimetric scanning laser ophthalmoscope and polarization sensitive optical coherence tomography. His PhD thesis "Imaging Polarimetry of Human Eye" is available on the following link.

>> PhD thesis on Tsukuba Repository

Joschi

New publication: 3D polarization sensitive OCT of glaucoma surgery

Our new paper is now published in Optics Express. This paper presents a case series of glaucoma surgeries measured by our three-dimensional polarization sensitive optical coherence tomography (3-D PS-OCT). Since this paper is an interactive scientific publication (SIP), full 3-D PS-OCT data sets of cases is downloadable in addition to conventional static picture-figures. You can download the datasets and can write your own signal processing software.

The manuscript is freely downloadable from Optics Express web-site.

>> Article in Optics Express

Citation: Y. Yasuno, M. Yamanari, K. Kawana, T. Oshika, and M. Miura, "Investigation of post-glaucoma-surgery structures by three-dimensional and polarization sensitive anterior eye segment optical coherence tomography," Opt. Express 17, 3980-3996 (2009).

Joschi, Yoshiaki Yasuno

New Publication: Retinal Shadow Compensation in Retinal OCT

Our new paper was published in Journal of Biomedical Optics Letters (JBO). This paper describes a simple but effective numerical algorithm to remove shadowing artifacts caused by retinal vessels in an optical coherence tomography (OCT) image. The paper is published in an open access manner, and available on JBO web site.

>>> [Abstract and PDF on JBO web site]

Citation: T. Fabritius, S. Makita, Y. Hong, R. Myllyla and Y. Yasuno, "Automated retinal shadow compensation of optical coherence tomography images," J. Biomed. Opt. 14, 010503 (2009).