Computational Optics Group Press Room

Journal paper: Choroidal optical coherence angiography with variable velocity range

2011-12-26T11:01:00.001+09:00

Non-invasive and three-dimensional angiography of choroid with several blood-velocity range is available now. Our colleague Franck Jaillon recently published the details of this methodology in Optics Express. In this paper he demonstrated non-invasive visualization of fine vasculature of the choroid of normal eyes. This technology is based on Doppler optical coherence tomography, and hence it is totally noninvasive and three-dimensional. The Doppler detection is performed with our original dual beam scan Doppler scheme, which provides extremely high Doppler sensitivity. In addition, this system uses a 1-um probe beam, it provides deep penetration into the choroid.

The details are described in the following paper.
>> Full length article on Journal web-site (open access)
Citation: F. Jaillon, S. Makita, Y. Yasuno, "Variable velocity range imaging of the choroid with dual-beam optical coherence angiography," Opt. Express 20, 385-396 (2012).

研究室秘書募集 (Closed)

2011-11-09T13:18:00.003+09:00

以下の募集は締め切りました

COG筑波大学では研究室の事務補助をおこなってくれる秘書さんを募集しています。

時給は1,130円程度（大学規定により多少の変更あり）で、勤務日数は週3日～4日程度です。勤務時間は朝10時ごろから夕方4時、5時ごろまで。(勤務日数、勤務曜日と時間は相談可）。
勤務開始日は採用後、出来るだけ早い時期を希望します。

興味のある方は履歴書を郵送、もしくは以下のメールアドレスまでご添付ください。
書類選考後、面接を行います。また、問合せも以下のメールアドレスまでお願いします。

yasuno@optlab2.bk.tsukuba.ac.jp
029-853-5217(呼出：安野）
安野嘉晃（やすのよしあき）

履歴書郵送先：　
〒305-8571 つくば市天王台1-1-1
筑波大学数理物質域

応募締切は 2011/11/26 （土）消印有効です。

勤務場所は"筑波大学第3エリアバス停横工学系学系 F棟"です。
下記URL内の地図、I-6にあります。
お車でお越しの際は、まず"外来専用駐車場"に停めていただき、F棟1階の受付に車を駐車する旨をお伝えください。
http://www.tsukuba.ac.jp/access/map_central.html

Journal Article: Office-Based Polarization Sensitive OCT for Anterior Eye

2011-07-26T08:00:00.000+09:00

Our colleague Yiheng Lim recently reported a clinical prototype of polarization sensitive optical coherence tomography (PS-OCT) specially designed for the investigation of anterior eye segments. This system based on our developed high-speed Jones matrix OCT methodology, and integrated with a scanning head specially designed for anterior eye imaging. This clinical prototype provides semi-automatic alignment function and possesses a compact, office-compatible size. Several clinical cases were investigated to prove the clinical utility.

The details are reported in Biomedical Optics Express.

>> Full length article on journal web-site (open access)

Citation: Y.H. Lim, M. Yamanari, S. Fukuda, Y. Kaji, T. Kiuchi, M. Miura, T. Oshika, and Y. Yasuno "Birefringence measurement of cornea and anterior segment by office-based polarization-sensitive optical coherence tomography," Biomed. Opt. Express 2, 2392-2402 (2011).

Journal Article: High-Sensitive Doppler Imaging of Choroid by Dual-Beam Doppler OCT

2011-04-10T08:00:00.000+09:00

Our colleague Franck Jaillon recently reported his new Doppler optical coherence tomography (OCT) system which enables high-penetration and dual-velocity imaging of choroidal vasculature. This methodology employed newly developed dual-beam OCT scanning head to provide high-sensitive Doppler imaging. Furthermore, this scanning head can provide multiple velocity range for Doppler detection. Since this system is using 1-um light as a probe, the details of in vivo choroidal vasculature was successfully visualized.

The details are published in Biomedical Optics Express.

>> Full length article on journal web-site (open access)

Citation: F. Jaillon, S. Makita, E.-J. Min, B.H. Lee, Y. Yasuno, "Enhanced imaging of choroidal vasculature by high-penetration and dual-velocity optical coherence tomography," Biomed. Opt. Express 2, 1147-1158 (2011).

Journal Article: Wettability Characterization by OCT

2010-10-14T10:20:00.003+09:00

Tapio Fabritius (Oulu University, Finland) recently published a paper in Optics Express in which the authors investigated the utility of optical coherence tomography (OCT) for the characterization of wettability of materials. The study presented was a collaboration between Oulu University and Computational Optics Group at the University of Tsukuba.

In the particular demonstration in this paper, a glycerol droplet on a rough surface was characterized, and the contact angles between them were automatically obtained.

The details are published in the following Optics Express paper.

>> Full length article on journal web site (open access)

Citation: T. Fabritius, R. Myllylä, S. Makita, and Y. Yasuno, "Wettability characterization method based on optical coherence tomography imaging," Optics Express 18, 22859-22866 (2010).

Journal Article: Full Range Polarization Sensitive OCT at 1-Micron

2010-06-16T09:55:00.003+09:00

Our colleague Masahiro Yamanari recently reported a new polarization sensitive optical coherence tomography (PS-OCT) for retinal and choroidal imaging. This new PS-OCT utilized a probe beam with 1-micron wavelength enabled high-penetration to the choroid, and a full range measurement scheme based on the modulation of reference beam of OCT (BM-scan). This system enables detailed investigation of birefringence property of the deep posterior eye.

After all, this OCT possesses a depth measurement range of 5.3 micrometers in air, a depth resolution of 11.4 micrometers in tissue, and a measurement speed of 30,000 depth-scan/sec. The intensity ratio between an OCT signal and its suppressed mirror signal was found to be 40.5 dB.

This PS-OCT is the first demonstration of 1-um PS-OCT with a clinically useful depth measurement range.

The details are available in the following Optics Express paper.

>> Full length article on Journal web site (open access)

Citation: M. Yamanari, S. Makita, Y. Lim, and Y. Yasuno, "Full-range polarization-sensitive swept-source optical coherence tomography by simultaneous transversal and spectral modulation," Opt. Express 18, 13964-13980 (2010).

Adaptive Optics Optical Coherence Tomography at One-Micron

2010-04-29T02:14:00.006+09:00

Our colleague Kazuhiro Kurokawa recently reported adaptive optics optical coherence tomography (AO-OCT) for posterior eye imaging. This AO-OCT uses one-micrometer wavelength probe, and is the world first demonstration of high-penetration AO-OCT.

In vivo measurement of human normal subject was performed. The OCT image clearly shows the crosssections of optic nerve fiber bundles as well as the interface between the choroid and sclera.

The details are reported in Optics Express.

>> Full article on journal website (open access)

Photonics West Bigins

2010-01-23T15:13:00.003+09:00

The biggest annual event of OCT community begins. BiOS, a part of SPIE Photonics West starts on Jun. 23rd. in San Francisco. Almost all members of COG are now rushing into that city. We have 7 oral presentations including 6 from our core member and 1 from our collaborator. See this page to see the abstracts and add our presentations to your conference agenda. Come and see our talks!

Saturday 23rd

[2:00pm-2:15pm, Room 306] S. Makita et al., "High-sensitive blood flow imaging of the retina and choroid by using double-beam optical coherence angiography."
[5:00pm-5:15pm, Room 306] Y. Lim et al., "Polarization Sensitive Corneal and Anterior Segment Swept-Source Optical Coherence Tomography."
[5:15pm-5:30pm, Room 306] A. Miyazawa et al., "Tissue discrimination in anterior eye using three optical parameters obtained by polarization sensitive optical coherence tomography."

Sunday 24th

[5:30pm-5:45pm, Room 306] Y. Ikuno et al., "Clinical application of high-penetration optical coherence tomography using 1060-nm wevelength."

Monday 25th

[1:00pm-1:15pm, Room 303] K. Kurokawa et al., "Adaptive optics spectral domain optical coherence tomography with one-micrometer light source."

Tuesday 26th

[11:15am-11:30am] F. Jaillon et al., "BM-mode scanning with parabolic phase modulation for full range Doppler optical tomography."

Wednesday 27th

[8:45am-9:00am] M. Yamanari et al., "Full range polarization-sensitive swept-source optical coherence tomography at 1-um with polarization modulation and BM-mode scan."

One-Micrometer Adaptive Optics for Scanning Laser Ophthalmoscope

2010-01-21T02:11:00.006+09:00

Our colleague Kazuhiro Kurokawa recently reported an adaptive optics scanning laser ophthalmoscope (AO-SLO) with a one-micrometer probe beam. This AO-SLO is the world first demonstration of an adaptive-optics based high-resolution retinal imager with this wavelength band. The mosaic of cone photoreceptors and the flow of blood cells of in vivo human eyes were visualized. The details were published in Optics Express.

>> Full article on the journal website (open access)

Full-Range Doppler OCT with High Dynamic Range

2010-01-14T03:29:00.006+09:00

Franck Jaillon from COG in the University of Tsukuba demonstrated a new full range spectral domain optical coherence tomography (OCT), so called parabolic BM-scan method. This method is a variation of full-range OCT based BM-scan method, but possesses higher tolerance to the sample motion and higher dynamic range of Doppler measurement. In this paper, in vivo investigation of human eye was performed, and it was found that this parabolic BM-scan method is useful for office-based in vivo measurements. The details of this method were published in Optics Express.

>> Article on the journal web site (open access)

Yasuno became associate editor of Optics Express

2010-01-13T13:59:00.008+09:00

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

2010-01-08T03:09:00.002+09:00

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

2010-01-07T16:09:00.005+09:00

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

2010-01-07T01:39:00.007+09:00

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

2009-09-16T01:59:00.006+09:00

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

2009-09-11T11:51:00.005+09:00

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

2009-09-11T00:53:00.005+09:00

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

2009-09-07T12:12:00.005+09:00

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

2009-09-01T13:47:00.004+09:00

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

2009-08-31T10:30:00.005+09:00

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

2009-07-14T11:26:00.004+09:00

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

2009-06-11T20:09:00.003+09:00

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

2009-06-11T19:58:00.003+09:00

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

2009-03-13T00:12:00.008+09:00

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

2009-02-25T19:06:00.000+09:00

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).

Kurokawa won Pascal Rol Award

2009-02-23T14:59:00.000+09:00

Kazuhiro Kurokawa (Computational Optics Group in the University of Tsukuba) was chosen as the best presenter and received Pascal Rol Award at Photonics West in January, 2009.

Pascal Rol Award was established for the promotion of ophthalmic technologies in the memory of Pascal Rol (University Eye Clinic, Zurich). This Pascal Rol Award is given to the best presented ophthalmic engineer at Photonics West.

Kurokawa was the one who gained acceptance with his research "one-micrometer wavelength adaptive optics scanning laser opthalmoscope."

Ishii

黒川氏がPascal Rol Award受賞

2009-02-23T14:56:00.010+09:00

先月米国にて開催されたPhotonics Westにおいて黒川和博氏（Computational Optics Group in the University of Tsukuba）が2009年のPascal Rol Awardを受賞しました。

Pascal Rol Award賞は2000年に急逝した著名な眼科光学研究者であるPascal Olivier Rol（チューリッヒ眼科大学病院、マイアミ大学）の功績を称えて設立されたものであり、Photonics Westにおいて最も優れた研究を公表した眼科工学研究者一人に贈られます。

今回はマサチューセッツ工科大学、ウィーン医科大学等からの他のノミネートを抑えて黒川氏が研究成果「1μm帯域光を利用したレーザー走査検眼鏡」を認められての受賞となりました。Computational Optics Groupでは2007年の安野嘉晃氏に続き二度目の受賞となります。

石井

New Publication: Investigation of photo-aging by PS-OCT

2009-02-19T15:44:00.004+09:00

A new paper was published by our project of polarization sensitive optical coherence tomography (PS-OCT) and skin investigation in Journal of Investigative Dermatology (JID). In this paper, we examined photo-aged skins of young and old subjects by PS-OCT and quantitatively analyzed the skin birefringence. In this study, we found that dermal birefringence of the cheek skin, which was well exposed by sun light, was significantly smaller in the old group than in the young group. On the other hand, the interior upper arm, which was normally exposed by sun light, showed no age-dependent difference.

The abstract and the full article are available on the journal web site and PubMed.

>>> [Article on JID site]

>>> [Abstract on PubMed]

Citation: S. Sakai, M. Yamanari, A. Miyazawa, M. Matsumoto, N. Nakagawa, T. Sugawara, K. Kawabata, T. yatagai, and Y. Yasuno, "In vivo three-dimensional birefringence analysis shows collagen differences between young and old photo-aged human skin," J. Inv. Dermatol. 128, 1641-1647 (2008).

Joschi, Yoshiaki Yasuno

Update of Publication: AMD and High-Penetration OCT

2009-02-19T15:21:00.003+09:00

Original article is on August 13, 2008

The following our paper is now officially published in Investigative Ophthalmology and Visual Science (IOVS).

Y. Yasuno, M. Miura, K. Kawana, S. Makita, M. Sato, F. Okamoto, M. Yamanari, T. Iwasaki, T. Yatagai, and T. Oshika, "Visualization of Sub-retinal Pigment Epithelium Morphologies of Exudative Macular Diseases by High-Penetration Optical Coherence Tomography," Inv. Ophthalmol. Vis. Sci. 50, 405-513 (2009).

This paper demonstrates the application of new OCT with one-micrometer probe wavelength (high-penetration OCT; HP-OCT) to age-related macular degeneration. 14 eyes were involved in this study, and the clinical utility of HP-OCT was discussed. Preliminary results which suggest higher robustness of HP-OCT to cataract than standard OCT were also shown. The paper is available on the journal web site (IOVS).

>>> [Abstract and PDF]

New publication: AMD and High-Penetration OCT

2008-08-13T09:52:00.004+09:00

Our new paper is now available as publish ahead of print of IOVS. This paper demonstrates the application of new OCT with 1 micrometer probe wavelength (high-penetration OCT; HP-OCT, also referred to as long probe OCT; LP-OCT) to age-related macular degeneration. 14 eyes were involved in this study, and the clinical utility of HP-OCT was discussed. Preliminary results which suggest higher robustness of HP-OCT to cataract than standard OCT were also shown. The paper is available on the journal web site (IOVS).
>>> [Abstract and PDF at IOVS web-site]

Title: Visualization of Sub-Retinal Pigment Epithelium and Sub-Choroidal Neovascularization Morphologies of Exudative Macular Diseases by Optical Coherence Tomography with Long Wavelength Probe
Authors: Y. Yasuno, M. Miura, K. Kawana, S.Makita, M. Sato, F. Okamoto, M. Yamanari, T. Iwasaki, T. Yatagai, T. Oshika
Journal: Investigative Ophthalmology & Vision Science
Volume/Page: publish ahead of print

Joschi, Yoshiaki Yasuno

講義資料：医療機器開発と産学連携

2008-06-17T08:45:00.003+09:00

Lecture Material: Collaboration of University and Industry for the Development of Medical Equipment
(See below for an English version)

応用理工学概論「医療機器開発と産学連携」の講義資料を公開します。いそいで作った出来の悪いマテリアルですが… 興味のある方はどうぞ。
- PDFをダウンロード

Joschi, 安野嘉晃

Here we release a Lecture Material of ``Collaboration of University and Industry for the Development of Medical Equipment.'' This material is for the lecture of``Introduction to Applied Science and Engineering,'' which is a general introduction for the 1st year students of our University (University of Tsukuba).
The material is still very primitive and written in English... But you can download it from the following URL.
- Download PDF

Joschi, Yoshiaki Yasuno

BiOS/ARVO2008 レポート (Only in Japanese)

2008-06-16T10:49:00.002+09:00

国際会議 SPIE BiOS/Photonics West 2008, および米眼科学会 ARVO 2008 の簡易レポートを公開します。第5回電気学会バイオメディカル・フォトニクス先端技術調査専門委員会（2008年6月16日）による報告のために作成されたレポートです。興味のある方は「安野による主観的なもの」であることをご承知の上でご参考ください。

PDFをダウンロード

Joschi, 安野嘉晃

Imaging Plarimetry in Age-Related Macular Degeneration

2008-06-05T14:46:00.004+09:00

Our new paper was published in Investigative Ophthalmology and Visual Science (IOVS).
[Download from Journal Web Site]

The details are following

Title: Imaging Polarimetry in Age-Related Macular Degeneration

Authors: Masahiro Miura, Masahiro Yamanari, Takuya Iwasaki, Ann E. Elsner, Shuichi Makita, Toyohiko Yatagai, and Yoshiaki Yasuno

Citation: Invest. Ophthalmo. Vis. Sci. 49, 2661-2667 (2008).

PURPOSE
To evaluate the birefringence properties of eyes with age-related macular degeneration (AMD). To compare the information from two techniques—scanning laser polarimetry (GDx) and polarization-sensitive spectral-domain optical coherence tomography (OCT)—and investigate how they complement each other.

METHODS
The authors prospectively examined the eyes of two healthy subjects and 13 patients with exudative AMD. Using scanning laser polarimetry, they computed phase-retardation maps, average reflectance images, and depolarized light images. To obtain polarimetry information with improved axial resolution, they developed a fiber-based, polarization-sensitive, spectral-domain OCT system and measured the phase retardation associated with birefringence in the same eyes.

RESULTS
Both GDx and polarization-sensitive spectral-domain optical coherence tomography detected abnormal birefringence at the locus of exudative lesions. Polarization-sensitive, spectral-domain OCT showed that in the old lesions with fibrosis, phase-retardation values were significantly larger than in the new lesions (P = 0.020). Increased scattered light and altered polarization scramble were associated with portions of the lesions.

CONCLUSIONS
GDx and polarization-sensitive spectral-domain OCT are complementary in probing birefringence properties in exudative AMD. Polarimetry findings in exudative AMD emphasized different features and were related to the progression of the disease, potentially providing a noninvasive tool for microstructure in exudative AMD.

Image of the week in Optics InfoBase

2008-06-05T13:13:00.009+09:00

The volume rendering image of the optic nerve head in our new publication entitled "Full-range, high-speed, high-resolution 1μm spectral-domain optical coherence tomography using BM-scan for volumetric imaging of the human posterior eye" was selected to "Image of the week" in Optics InfoBase.

New publication: Full-range, high-speed 1um SD-OCT

2008-05-24T01:16:00.004+09:00

Full-range, high-speed, high-resolution 1μm spectral-domain optical coherence tomography using BM-scan for volumetric imaging of the human posterior eye

This our paper is now available on Optics Express.

>>[Abstract and PDF]

Citation
S. Makita, T. Fabritius, and Y. Yasuno, "Full-range, high-speed, high-resolution 1μm spectral-domain optical coherence tomography using BM-scan for volumetric imaging of the human posterior eye," Opt. Express 16, 8406-8420 (2008).

Abstract
An alternative optical coherence tomography (OCT) to clinical ophthalmic 830 nm spectral-domain OCTs (SD-OCT) is demonstrated. An axial resolution of 7.4 μm, ranging depth of 4.2 mm in tissue, sensitivity of 98.5 dB, and detection speed of 38,300 axial scans/s have been achieved. These are comparable or superior to those of recently commercially available ophthalmic 830 nm SD-OCTs in clinics. In addition, fast volumetric imaging for the in vivo human posterior eye with high-contrast of the choroid is achieved. A broadband 1.04 μm light source enables the high-contrast and high resolution imaging of the retina and choroid. The ranging depth is extended by applying a full-range imaging method with an electro-optic modulator (BM-scan method). A prototype high-speed InGaAs line scan camera with 1024 pixels is used. A newly reported sensitivity improvement property of the BM-scan method demonstrates a sensitivity enhancement of 5.1 dB. We also introduce a newly developed resampling calibration method of spectrum that is independent of the intrinsic dispersion mismatch of the interferometer. The three-dimensional structure of the in vivo human optic nerve head with a very deep cupping is successfully visualized.

New publication: PS-SS-OCT

2008-04-12T23:20:00.003+09:00

Now the paper about PS-SS-OCT with continuous source polarization modulation is available on Optics Express.

M. Yamanari, S. Makita, and Y. Yasuno, "Polarization-sensitive swept-source optical coherence tomography with continuous source polarization modulation," Opt. Express 16, 5892-5906 (2008)
http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-8-5892

Abstract
We present fiber-based polarization-sensitive swept-source optical coherence tomography (SS-OCT) based on continuous source polarization modulation. The light source is a frequency swept laser centered at 1.31 μm with a scanning rate of 20 kHz. The incident polarization is modulated by a resonant electro-optic modulator at 33.3 MHz, which is one-third of the data acquisition frequency. The zeroth- and first-order harmonic components of the OCT signals with respect to the polarization modulation frequency have the polarimetric information of the sample. By algebraic and matrix calculations of the signals, this system can measure the depth-resolved Jones matrices of the sample with a single wavelength scan. The phase fluctuations of the starting trigger of wavelength scan and the polarization modulation are cancelled by monitoring the OCT phase of a calibration mirror inserted into the sample arm. We demonstrate the potential of the system by the measurement of chicken breast muscle and the volumetric measurement of an in vivo human anterior eye segment. The phase retardation image shows an additional contrast in the fibrous tissue such as the collagen fiber in the trabecular meshwork and sclera.

New publicationo: Quantitative Doppler OCT

2008-04-11T12:15:00.008+09:00

Quantitative retinal-blood flow measurement with three-dimensional vessel geometry determination using ultrahigh-resolution Doppler optical coherence angiography

Our new paper was just published on Optics Letters.
This paper is open access and freely available on the follwoing link.

>> [Abstract and PDF]

Citation
S. Makita, T. Fabritius, and Y. Yasuno, "Quantitative retinal-blood flow measurement with three-dimensional vessel geometry determination using ultrahigh-resolution Doppler optical coherence angiography," Opt. Lett. 33, 836-838 (2008)

Abstract
Retinal blood flow quantification by retinal vessel segmentation with Doppler optical coherence angiography is presented. Vessel diameter, orientation, and position are determined in an en face vessel image and two representative cross-sectional flow images of the vessel. Absolute blood flow velocity is calculated with the help of the measured Doppler frequency shift and determined vessel angle. The volumetric flow rate is obtained with the position and the region of the vessel lumen. The volumetric blood flow rate of retinal arteries before and after a bifurcation is verified in a healthy human eye.

光計測シンポジウム

2007-06-05T01:25:00.000+09:00

今週水曜日（２００７年６月６日）、パシフィコ横浜にて開催される光計測シンポジウムにおいてＣＯＧ安野が「前眼部用ＯＣＴによる臨床試験」と題して研究発表を行います。

現在ＣＯＧと筑波大学眼科、東京医科大学眼科で共同開発を行っている前眼部用３次元ＯＣＴを用いた臨床検査の結果報告。現在まで行った実際の患者さんを対象とした臨床検査の中から、３次元ＯＣＴならでは特徴的な症例を中心に紹介します。詳細は以下をご参考ください。

日時： 2007年６月６日（水）午前１０時より
場所：パシフィコ横浜
公式サイト：光計測シンポジウム

Joschi

COG オフィシャルチャットルーム

2007-06-05T00:45:00.001+09:00

Skype Open Chat を利用した COG オフィシャルチャットルームを開設しました。このリンクをクリック、またはこのブログ右上のリンクあから Chat Room へ。技術屋/臨床屋のおしゃべりの場としてご利用ください。

注）利用にはSkypeが必要です。Skype Open Chat に関してはこのページをご覧下さい

Joschi

私（安野）もぶらぶらしているので、いたら声掛けてください。

Paper published: Line-field SD-OCT

2007-06-04T23:35:00.001+09:00

Our paper "High-speed three-dimensional human retinal imaging by line-field spectral domain optical coherence tomography" was published in Optics Express. This paper describes a high-speed parallel spectral domain optical coherence tomography system and its optimization for in vivo retinal imaging. This system has the measurement speed of 823,200 A-lines/s for a single frame cross-sectional measurement and 51,500 A-lines/s for a three-dimensional volumetric measurement. The sensitivity was measured to be 89.4 dB with a probe power of 112 uW, and the axial resolution was measured to be 7.4 um.

This article is open access and downloadable from this page.

Joschi

COG appears at ARVO

2007-05-07T20:02:00.000+09:00

We COG appears at ARVO conference in Fort Lauderdale, Florida, USA.We give 10 presentations including 3 paper presentations.

Search the presentations at the official site of ARVO.

See you at ARVO!

1um SS-OCT + S-OCA paper appeared in Optics Express

2007-05-07T12:03:00.000+09:00

Our paper "In vivo high-contrast imaging of deep posterior eye by 1-um swept source optical coherence tomography and scattering optical coherence angiography" was published in Optics Express;

Y. Yasuno, Y. Hong, S. Makita, M. Yamanari, M. Akiba, M. Miura, and T. Yatagai, "In vivo high-contrast imaging of deep posterior eye by 1-um swept source optical coherence tomography and scattering optical coherence angiography," Opt. Express 15, 6121-6139 (2007).

This paper is freely downloadable from the web site of Optics Express.

(Link to Optics Exress)

People

2007-01-01T01:00:00.003+09:00

Faculty staff

Yoshiaki Yasuno (Assistant Professor, Group Leader)

Postdoctoral researchers

PhD candidates

Arata Miyazawa

Master course student

Kazuhiro Kurokawa

Bachelor course students

External members

Masahiro Miura (MD, Associate Professor from Tokyo Medical University)

Student workers

Daiki Tamada (MIR Lab., University of Tsukuba)

About us

2007-01-01T01:00:00.001+09:00

The computational optics group (COG) was formed in 1999 as a division of applied optics laboratory, institute of applied physics, university of Tsukuba. On that moment we were not COG but spatio-temporal optics group, and our main research subject was spatio-temporal optical computing.

In 2000, we started a optical measurement project using spatio-temporal optical computing technologies, and in 2002, we changed our direction to more computationally.

Since 2002, our main research interest is computer assisted optical measurment. We are trying to introduce computational technologies into optical measurement.

Since 2007, we are an independent research group and no longer a part of Applied Optics Laboratory of University of Tsukuba.

Contact and Access

2007-01-01T00:00:00.000+09:00

Map

View COG office in a larger map

Access to COG Office

From Tokyo:

Take Tsukuba Express train to Tsukuba station.
Take a bus to Tsukuba-Daigaku-Chuo (Center of Tskuba University, 筑波大学中央) or Tsukuba-Daigaku-Junkan Migi-Mawari (Tsukuba University Shuttle/Right circular path, 筑波大学循環右回).
The closest bus-stop to our office is Daisan-Eria-Mae (3rd Area of the University, 第3エリア前). When you get off the bus, you'll see a tall brown building (Building-F of Institute of Engineering, 工学系F棟). Our office is at the 7th floor of this building, room 702. Note that the frequency of the bus is around every 10-15 min.

From Narita (New Tokyo) Airport:

There is a direct bus to Tsukuba bus-center (next to Tsukuba station). From Narita to Tsukuba, reservation is not required, and you can buy a bus ticket at Narita Airport. The timetable is available on this page.
From Tsukuba bus-center, take a bus to Tsukuba-Daigaku-Chuo (Center of Tskuba University, 筑波大学中央) or Tsukuba-Daigaku-Junkan Migi-Mawari (Tsukuba University Shuttle/Right circular path, 筑波大学循環右回).
The closest bus-stop to our office is Daisan-Eria-Mae (3rd Area of the University, 第3エリア前). When you get off the bus, you'll see a tall brown building (Building-F of Institute of Engineering, 工学系F棟). Our office is at the 7th floor of this building, room 702. Note that the frequency of the bus is around every 10-15 min.

From Haneda (Tokyo) Airport:

There is a direct bus to Tsukuba bus-center (next to Tsukuba station). From Haneda to Tsukuba, reservation is not required, and you can buy a bus ticket at Haneda Airport. The timetable is available on this page.
From Tsukuba bus-center, take a bus to Tsukuba-Daigaku-Chuo (Center of Tskuba University, 筑波大学中央) or Tsukuba-Daigaku-Junkan Migi-Mawari (Tsukuba University Shuttle/Right circular path, 筑波大学循環右回).
The closest bus-stop to our office is Daisan-Eria-Mae (3rd Area of the University, 第3エリア前). When you get off the bus, you'll see a tall brown building (Building-F of Institute of Engineering, 工学系F棟). Our office is at the 7th floor of this building, room 702. Note that the frequency of the bus is around every 10-15 min.

Contact

Phone/Fax: +81-29-853-5217
E-mail: cogoffice@optlab2.bk.tsukuba.ac.jp
Institute of Applied Physics, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, 305-8573, Japan

Computational Optics Group Press Room

Journal paper: Choroidal optical coherence angiography with variable velocity range

研究室秘書募集 (Closed)

Journal Article: Office-Based Polarization Sensitive OCT for Anterior Eye

Journal Article: High-Sensitive Doppler Imaging of Choroid by Dual-Beam Doppler OCT

Journal Article: Wettability Characterization by OCT

Journal Article: Full Range Polarization Sensitive OCT at 1-Micron

Adaptive Optics Optical Coherence Tomography at One-Micron

Photonics West Bigins

One-Micrometer Adaptive Optics for Scanning Laser Ophthalmoscope

Full-Range Doppler OCT with High Dynamic Range

Yasuno became associate editor of Optics Express

Generalized Jones Matrix OCT

Investigation of Choroidal Thickness

Birefringence Imaging of Necrotizing Scleritis

Tissue Discrimination Imaging of Anterior Eye

Ocular Biometry by 3D-OCT

3D Investigation of Glaucoma Surgery

Publication: OCT guided surgery of cornea

New Publication: Dermal Birefringence and Skin Surface

New Publication: Segmentation of Retinal Pigment Epithelium

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

SPIE Newsroom: Multifunctional Anterior OCT

Our Ophthalmologist receives PhD of Engineering

New publication: 3D polarization sensitive OCT of glaucoma surgery

New Publication: Retinal Shadow Compensation in Retinal OCT

Kurokawa won Pascal Rol Award

黒川氏がPascal Rol Award受賞

New Publication: Investigation of photo-aging by PS-OCT

Update of Publication: AMD and High-Penetration OCT

New publication: AMD and High-Penetration OCT

講義資料： 医療機器開発と産学連携

BiOS/ARVO2008 レポート (Only in Japanese)

Imaging Plarimetry in Age-Related Macular Degeneration

Image of the week in Optics InfoBase

New publication: Full-range, high-speed 1um SD-OCT

New publication: PS-SS-OCT

New publicationo: Quantitative Doppler OCT

光計測シンポジウム

COG オフィシャルチャットルーム

Paper published: Line-field SD-OCT

COG appears at ARVO

1um SS-OCT + S-OCA paper appeared in Optics Express

People

About us

Contact and Access

講義資料：医療機器開発と産学連携