Hiroko Iwashita

Dr. Hiroko Iwashita

Toho University
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
27 July 2020 in Veterinary Ophthalmology
Verified
Journal Article
Closed access
PDF file
HIHiroko Iwashita
Hiroko Iwashita
SWShinsuke Wakaiki
Shinsuke Wakaiki
YKYoshiyuki Kazama
Yoshiyuki Kazama
ASAkihiko Saito
Akihiko Saito

27 December 2022 in Veterinary Ophthalmology
Verified
Journal Article
Closed access
HIHiroko Iwashita
Hiroko Iwashita
LSLionel Sebbag
Lionel Sebbag
BLBrian C. Leonard
Brian C. Leonard
ASAkihiko Saito
Akihiko Saito

4 February 2019 in Veterinary Ophthalmology
Verified
Journal Article
Open access
PDF file
YKYasunari Kitamura
Yasunari Kitamura
SMSeiya Maehara
Seiya Maehara
TNTetsuya Nakade
Tetsuya Nakade
YMYukihiro Miwa
Yukihiro Miwa
RAReiko Arita
Reiko Arita
ASAkihiko Saito
Akihiko Saito
Objective: To investigate meibomian gland (MG) morphology by noncontact infrared meibography in Shih Tzu dogs with or without keratoconjunctivitis sicca (KCS).Procedures: Fourteen eyes of 12 Shih Tzu dogs (mean age of 10.7 years, range of 7‐13 years) presented to Yakumo Animal Hospital or Triangle Animal Eye Clinic from 2011 to 2017 with clinical signs and a Schirmer tear test (STT) result consistent with KCS ( 15 mm/min served as healthy controls. Both groups of dogs underwent routine slitlamp biomicroscopy followed by noncontact infrared meibography of the upper eyelid with both desktop‐type and mobile‐type systems.Results: Meibography revealed morphological abnormalities of MGs in 13 eyes of 11 dogs with KCS. The abnormalities included gland shortening in 64% and gland dropout in 64% of the 14 eyes in the KCS group. Morphological changes were also observed in MGs of 16 eyes of 10 dogs in the control group. These changes included shortening in 46% and dropout in 17.8% of the 28 eyes in the control group. Dropout was significantly more common in eyes with KCS than in control eyes (P < 0.01).Conclusions: The frequency of MG abnormalities is increased in Shih Tzus with KCS compared with control animals. A reduced quality of the tear film associated with increased evaporation and reduced retention of tear fluid likely exacerbates the effects of a reduced tear volume in animals with aqueous deficiency.

21 March 2019 in Veterinary Ophthalmology
Verified
Journal Article
Closed access
PDF file
KMKeiichi Miyasaka
Keiichi Miyasaka
YKYoshiyuki Kazama
Yoshiyuki Kazama
HIHiroko Iwashita
Hiroko Iwashita
SWShinsuke Wakaiki
Shinsuke Wakaiki
ASAkihiko Saito
Akihiko Saito

1 February 2018 in Investigative Ophthalmology & Visual Science
Verified
Journal Article
Open access
PDF file
TITakashi Itokawa
Takashi Itokawa
YOYukinobu Okajima
Yukinobu Okajima
TSTakashi Suzuki
Takashi Suzuki
KKKoji Kakisu
Koji Kakisu
HIHiroko Iwashita
Hiroko Iwashita
YHYuichi Hori
Yuichi Hori
Purpose: To investigate the correlation between the changes in the ocular surface temperature (OST) and tear film stability over soft contact lenses (SCLs). Methods: We enrolled 20 eyes of 20 normal SCL wearers (20 men; 24.4 ± 4.1 years). We used four different daily disposable SCLs: one silicone hydrogel lens (delefilcon A) and three hydrogel lenses (etafilcon A with polyvinylpyrrolidone [PVP], etafilcon A, and polymacon). OST was measured every second during 10 seconds without blinking. We defined the difference in the OST from 0 to 10 seconds as ΔOST. To evaluate tear film stability, we measured noninvasive tear break-up time (NIBUT) and tear interference patterns on the contact lenses (TIPCL) using tear film interferometry. The parameters were measured before and 15 minutes after wearing each SCL. Results: ΔOST was correlated significantly with NIBUT without (r = 0.411, P < 0.01) and with SCL (r = 0.642, P < 0.01). TIPCL grade was correlated significantly with ΔOST over SCLs (r = −0.636, P < 0.01). ΔOST was significantly smaller with silicone hydrogel delefilcon A than hydrogel etafilcon A and polymacon lenses (P < 0.05 and P < 0.01, respectively). Delefilcon A and etafilcon A with PVP lenses had significantly smaller NIBUT than etafilcon A (P < 0.05 for both comparisons). TIPCL grade of delefilcon A lens was significantly smaller than those of etafilcon A and polymacon (P < 0.01 for both comparisons). Conclusions: The changes in OST over SCLs are related to tear film stability. Measurements of OST can be used to evaluate tear film stability for SCL wearers.

12 November 2018 in Journal of Feline Medicine and Surgery
Verified
Journal Article
Closed access
LULisa K Uhl
Lisa K Uhl
ASAkihiko Saito
Akihiko Saito
HIHiroko Iwashita
Hiroko Iwashita
DMDavid J Maggs
David J Maggs
Jonathan MochelJonathan Mochel
Jonathan Mochel
LSLionel Sebbag
Lionel Sebbag
Objectives: The aim of this study was to describe the clinical findings, diagnostic test results and response to therapy of cats with Schirmer tear test 1 (STT-1) values below the reference interval. Methods: The medical records of three institutions were searched for cats with ocular surface disease and STT-1 values <9 mm/min, confirmed at two or more separate visits. Results: Ten cats (17 eyes) were included. The mean ± SD (range) age and STT-1 values in affected eye(s) were 6.1 ± 5.7 (0.2–16) years and 2.4 ± 3.1 (0–8) mm/min, respectively. Concurrent ocular surface disease was bilateral in 5/10 cats. Clinical signs included conjunctivitis (14/17 eyes), corneal ulceration (6/17 eyes), non-ulcerative keratitis (4/17 eyes), symblepharon (4/17 eyes), eosinophilic keratitis (3/17 eyes), corneal sequestrum (3/17 eyes), corneal fibrosis (2/17 eyes) and meibomitis (2/17 eyes). Management included: topically applied lacrimomimetics, antiviral drugs, corticosteroids or immunomodulatory drugs; orally administered famciclovir; or surgical procedures, in various combinations. Response to therapy (defined as an increase in STT-1 value of ⩾5 mm/min) was transient (seen at a single reassessment) in 65% of eyes and sustained (seen at ⩾2 consecutive reassessments) in 18% of eyes. Conclusions and relevance: Clinical features seen in cats with low STT-1 values are described, although the association between aqueous deficiency and the reported ocular changes is unknown at this time. We encourage clinicians to assess the tear film in cats with ocular surface disease, and initiate therapy with lacrimomimetics if STT-1 values are repeatedly below normal. Such information will further define aqueous tear deficiency in cats, providing a better understanding of disease prevalence, pathogenesis and treatment.