Torii, Hidemasa



School of Medicine, Department of Ophthalmology (Shinanomachi)


Senior Assistant Professor (Non-tenured)/Assistant Professor (Non-tenured)

Career 【 Display / hide

  • 2004.05

    横浜市立市民病院, 臨床研修医

  • 2006.04

    慶應義塾大学医学部, 眼科学教室, 専修医

  • 2007.10

    けいゆう病院, 眼科

  • 2009.04

    慶應義塾大学医学部, 眼科学教室, 助教

  • 2015.07

    慶應義塾大学医学部, 眼科学教室, 特任助教

Academic Background 【 Display / hide

  • 1998.04

    Keio University, School of Medicine

    Japan, University, Graduated

Academic Degrees 【 Display / hide

  • 博士(医学), Keio University, Dissertation, 2014.02

Licenses and Qualifications 【 Display / hide

  • 医師免許, 2004.05

  • 保険医, 2004.06

  • 眼科専門医, 2010.10

  • 日本医師会認定健康スポーツ医, 2015.03


Research Areas 【 Display / hide

  • Ophthalmology

Research Keywords 【 Display / hide

  • 屈折異常

  • 白内障

  • 近視

Research Themes 【 Display / hide

  • 屈折異常, 


  • 白内障, 


  • 近視, 


Proposed Theme of Joint Research 【 Display / hide

  • 近視

    Interested in joint research with industry (including private organizations, etc.),  Desired form: Technical Consultation, Funded Research, Cooperative Research


Papers 【 Display / hide

  • Ray tracing software for intraocular lens power calculation after corneal excimer laser surgery

    Saiki Megumi, Negishi Kazuno, Kato Naoko, Torii Hidemasa, Dogru Murat, Tsubota Kazuo

    Japanese Journal of Ophthalmology 58 ( 3 ) 276 - 281 2014

    ISSN  0021-5155

     View Summary

    <p>Purpose: To evaluate the accuracy of intraocular lens (IOL) power calculations using ray tracing software in eyes after myopic laser in situ keratomileusis (LASIK). Methods: Twenty-four eyes of 17 cataract patients who underwent phacoemulsification and IOL implantation after myopic LASIK were analyzed retrospectively. The IOL power calculation was performed using OKULIX ray tracing software. The axial length was measured using the IOLMaster and keratometry data using TMS2N. The accuracy of the IOL power calculation using OKULIX was compared with those using the Camellin-Calossi, Shammas-PL, Haigis-L formulas and the double-K SRK/T formula using 43.5 diopters (D) for the Kpre. Results: The mean values of the arithmetic and absolute prediction errors were 0.63 ± 0.85 and 0.80 ± 0.68 D, respectively. The arithmetic prediction error by OKULIX was a significant hyperopic shift of the distribution of the postoperative refractive errors compared to the Camellin-Calossi, Shammas-PL and Haigis-L formulas (P &lt; 0.05), and the absolute prediction error showed no significant difference with other formulas. The prediction errors using OKULIX were within ±0.5 D in 10 eyes (41.7 %) and within ±1.0 D in 18 eyes (75.0 %). The percentages of eyes within ±1.0 D using OKULIX were comparable to those obtained using the Camellin-Calossi, the Shammas-PL formulas and the double-K SRK/T formula using 43.5 D for the Kpre, and significantly (P &lt; 0.05) higher than that obtained using the Haigis-L formula. Conclusions: IOL power calculations using OKULIX provided predictable outcomes in eyes that had undergone a previous myopic LASIK. © 2014 Japanese Ophthalmological Society.</p>

  • Clinical results of toric intraocular lens implantation for cataract with high astigmatism

    Tominaga Takashi, Torii Hidemasa, Watanabe Kazuhiro, Shimizu Tsutomu, Saiki Megumi, Negishi Kazuno, Tsubota Kazuo

    Japanese Journal of Clinical Ophthalmology 68 ( 9 ) 1279 - 1283 2014

    ISSN  0370-5579

     View Summary

    <p>Purpose: To evaluate the postoperative outcome of toric intraocular lens (TIOL) implantation for cataract patients with high corneal astigmatism. Methods: This retrospective study included 24 eyes of 22 patients with high corneal astigmatism exceeded-1.50 D who underwent cataract surgery and implantation of TIOL (SN6AT6:12 eyes, SN6AT7:8 eyes, SN6AT8:3 eyes, SN6AT9:1 eye). The mean age of all cases was 68.1 years. Visual acuity, corneal astigmatism, subjective refraction, and rotation error were recorded preoperatively and 1 month postoperatively. Results: The uncorrected and correted distance visual acuities and subjective refraction were significantly (p&lt;0.001) improved after TIOL implantation. There was no significant difference in corneal astigmatism between preoperatively and postoperatively. The mean rotation error was 2.8°. Conclusion: TIOL was effective for cataract patients with high corneal astigmatism.</p>

  • Myopic regression after phakic intraocular lens implantation and LASIK

    Torii Hidemasa, Negishi Kazuno, Watanabe Kazuhiro, Arai Hiroyuki, Kato Naoko, Tsubota Kazuo

    Optometry and Vision Science 91 ( 2 ) 231 - 239 2014.02

    ISSN  1040-5488

     View Summary

    <p>PURPOSE: In myopia, biometry including the axial length is important, along with the refractive data. We compared the rates of myopic regression 3 years after phakic intraocular lens (pIOL) implantation and laser in situ keratomileusis (LASIK) after matching the preoperative axial length in highly myopic eyes of Japanese patients. METHODS: This retrospective nonrandomized study included 133 eyes of 84 patients with myopia exceeding -6.00 diopters (D) who underwent implantation of two iris-fixated pIOLs (pIOL group, 66 eyes/46 patients) or myopic LASIK (LASIK group, 67 eyes/38 patients) who were followed for more than 3 years postoperatively. The patient age, preoperative refraction, and preoperative axial length were matched between the study groups. RESULTS: There were no significant differences preoperatively between the groups in age, intraocular pressure, refraction, keratometry, or axial length. The mean regression values after 3 years compared with the 1-month postoperative refractions were -0.12 ± 0.47 (SD) D in the pIOL group and -0.82 ± 0.69 D in the LASIK group (p &lt; 0.001). The differences in the mean regression rates between 1 and 12 months, 12 and 24 months, and 24 and 36 months of follow-up were, respectively, 0.09 ± 0.38 D, -0.11 ± 0.35 D, and -0.11 ± 0.30 D in the pIOL group and -0.57 ± 0.84 D, -0.24 ± 0.47 D, and 0.00 ± 0.53 D in the LASIK group (p &lt; 0.001, p = 0.07, p = 0.15, respectively). CONCLUSIONS: There was a significant difference in myopic regression 3 years postoperatively between the groups matched for preoperative axial length in Japanese patients. This result has the potential to elucidate myopia in the future. Copyright © 2014 American Academy of Optometry.</p>

  • Secondary implantation of piggyback intraocular lens for residual refractive error after cataract surgery

    Kobayashi Fumitaka, Torii Hidemasa, Negishi Kazuno, Watanabe Kazuhiro, Saiki Megumi, Tsubota Kazuo

    Japanese Journal of Clinical Ophthalmology 67 ( 10 ) 1679 - 1684 2013.10

    ISSN  0370-5579

     View Summary

    <p>Purpose: To report a case who received implantation of piggyback intraocular lens (IOL) for residual refractive error after cataract surgery. Case: A 70-year-old man presented to our clinic complaining of decreased visual acuity in his both eyes. Both eyes had received radial keratotomy 23 years before and photorefractive keratectomy 12 years before. Findings: Visual acuity was 0.5 right and 0.4 left without correction, and 0.9 right and 1.0 left with correction. Under diagnosis of age-related cataract, both eyes received phacoemulsification-aspiration with IOL implantation. Visual acuity was 0.5 in either eye without correction and 1.2 right and 1.0 left with correction one year later. The left eye had refraction of +3.00D()cyl-2.00D 65°. By request of the patient, monofocal piggyback IOL was implanted into the left eye. Six months after surgery, left visual acuity was 0.63 without and 1.0 with correction. There has been no complication throughout. Conclusion: Implantation of piggyback IOL can be a therapeutic option for residual refractive error after cataract surgery.</p>

  • Changes in higher-order aberrations after iris-fixated phakic intraocular lens implantation

    Torii Hidemasa, Negishi Kazuno, Watanabe Kazuhiro, Saiki Megumi, Kato Naoko, Tsubota Kazuo

    Journal of Refractive Surgery 29 ( 10 ) 693 - 700 2013.10

    ISSN  1081-597X

     View Summary

    <p>PURPOSE: To evaluate surgically induced changes in corneal, internal, and ocular higher-order aberrations (HOAs) after phakic intraocular lens (PIOL) implantation and compare them between two PIOLs with different pupillary diameters. METHODS: Twenty-three eyes with an Artisan PIOL (Ophtec BV, Groningen, The Netherlands) (Artisan group) and 30 eyes with an Artiflex PIOL (Ophtec BV) (Artiflex group) were retrospectively evaluated. The corneal, internal, and ocular HOAs and refractive data were recorded preoperatively and 6 months postoperatively. The root mean squares (RMSs) of the total HOAs from the third- to sixth-order Zernike coefficients were calculated. The RMSs of the third- and fourth-order coefficients represented coma-like aberrations (S3) and spherical-like aberrations (S4), respectively. The main outcome measures were the differences in the parameters among the groups with different pupillary diameters. RESULTS: The mean postoperative spherical equivalents decreased from -11.84 ± 4.90 to -0.16 ± 0.40 diopters and -9.78 ± 3.20 to -0.09 ± 0.26 diopters in the Artisan and Artiflex groups, respectively. With the 4- and 5-mm pupillary diameters, the postoperative internal and ocular spherical aberrations (Z40) were significantly lower in the Artiflex group than in the Artisan group (4 mm, P = .002, .024; 5 mm, P = .004, .022, respectively). With the 6-mm pupillary diameter, there were no significant postoperative differences in any parameter measured between groups; both groups had positive spherical aberration values. CONCLUSIONS: The postoperative ocular spherical aberrations were positive after Artisan and Artiflex implantation. The postoperative ocular spherical aberration was greater in the Artisan group, possibly due to differences in the SAs of both PIOLs. Copyright © SLACK Incorporated.</p>

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

  • 術前一発マーキング法 ” のすゝめ ~トーリック眼内レンズの導入施設からエキスパートまで~

    Torii Hidemasa

    HOYA Technical News 26 (HOYA株式会社 メディカル事業部)     1 - 8 2015

    Institution technical report and pre-print, etc., Single Work

  • 乱視の診療 update – [乱視の疫学] – 乱視の分布と加齢変化 

    Torii Hidemasa

    Monthly Book OCULISTA (全日本病院出版会)  29   1 - 6 2015

    Introduction and explanation (scientific journal), Single Work

  • 屋外活動と近視抑制

    Torii Hidemasa

    IOL&RS (日本白内障屈折矯正手術学会雑誌編集部)  29 ( 2 ) 220 - 223 2015

    Introduction and explanation (scientific journal), Single Work

  • 期待のホープ

    Torii Hidemasa

    IOL&RS (日本白内障屈折矯正手術学会雑誌編集部)  25 ( 4 ) 600-604 2011

    Other article, Single Work

  • LASIKの周術期管理


    IOL&RS (日本白内障屈折矯正手術学会雑誌編集部)  24 ( 4 ) 580-584 2010

    Introduction and explanation (scientific journal), Joint Work

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Presentations 【 Display / hide

  • New approaches to prevention of myopia. Optical reduction of peripheral hyperopic defocus.

    Torii Hidemasa

    European Association for Vision and Eye Research 2015. (Nice, France.) , 2015.10, Symposium, Workshop, Panelist (nomination)

  • Peripheral refraction and outdoor activity may independently affect axial elongation.

    Torii Hidemasa

    2015 International Myopia Conference (Wenzhou, China) , 2015.09, Poster (general)

  • 近視進行抑制における屋外活動の重要性

    Torii Hidemasa

    第30回JSCRS学術総会, 2015.06, Oral Presentation(general)

  • 白内障術中トラブル対処 3ピース眼内レンズのメリット.-眼内レンズ挿入の基本手技とトラブルシューティング-

    Torii Hidemasa

    第30回JSCRS学術総会 (東京) , 2015.06, Symposium, Workshop, Panelist (nomination)

  • みんなで考える白内障手術.-QOVにこだわろう-  

    Torii Hidemasa

    第30回JSCRS学術総会 (東京) , 2015.06, Symposium, Workshop, Panelist (nomination)

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • 特定波長可視光線の近視進行抑制作用メカニズムの追究と環境・疫学調査


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 鳥居 秀成, Grant-in-Aid for Early-Career Scientists , Principal Investigator

  • Comparison of suppression effect of myopia progression focusing on mTOR signaling, ultraviolet light, and antioxidant


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 鳥居 秀成, Grant-in-Aid for Young Scientists (B), Principal Investigator

     View Summary

    We focused on violet light (VL, 360~400 nm wavelength), which is abundant in outdoor environments, and carried out research using a chick myopia model. Through that model, myopic progression of chicks exposed to VL was suppressed, and early growth response 1 (EGR1) was confirmed to be upregulated in chicks exposed to VL. In addition, the research also suggests that those wearing contact lenses that transmit VL suppress myopia progression more than those wearing contact lenses or glasses that do not transmit VL, suggesting that myopia progresses when wearing glasses that do not transmit VL. Furthermore, the LEDs and fluorescent lamps often used today contain little VL, and it was found that VL does not pass through materials such as the UV-protected eyeglasses and window glass. That is, in modern society there is a lack of VL, which may be related to the global increase in myopia.

Awards 【 Display / hide

  • American Society of Cataract and Refractive Surgery Annual Meeting 2018 Film Festival Grand Prize

    2018.04, American Society of Cataract and Refractive Surgery

  • 三四会奨励賞



Courses Taught 【 Display / hide