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Dive into the research topics where Yumi Hasegawa is active.

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Featured researches published by Yumi Hasegawa.


Retina-the Journal of Retinal and Vitreous Diseases | 2012

Time course of changes in aqueous flare intensity after vitrectomy for rhegmatogenous retinal detachment.

Sujin Hoshi; Fumiki Okamoto; Yumi Hasegawa; Yoshimi Sugiura; Yoshifumi Okamoto; Takahiro Hiraoka; Tetsuro Oshika

Purpose: To investigate the time course of changes in aqueous flare intensity after vitrectomy for rhegmatogenous retinal detachment (RD) and to determine the clinical factors related to an increase in aqueous flare. Methods: The present study included 22 unilateral patients with RD undergoing primary 20-gauge vitrectomy. Aqueous flare intensity was measured preoperatively and at 1 week, 2 weeks, 1 month, and 3, 6, and 12 months postoperatively using the laser flare meter. Results: Before vitrectomy, aqueous flare intensity was significantly higher in eyes with RD than in contralateral normal eyes. Vitrectomy increased aqueous flare intensity, and the peak was observed at the first postoperative week. Aqueous flare intensity decreased to a stable level at 3 months postoperatively but remained significantly higher than that of contralateral and preoperative eyes throughout the observation period. Clinical factors that were found to be significantly correlated with an increase in aqueous flare intensity included 1) before the surgical procedure: extent of RD and intraocular pressure, and 2) 3 months postoperatively: size of retinal breaks, number of laser photocoagulation spots, operation time, and performance of combined cataract surgery. Multiple regression analysis revealed that aqueous flare intensity at 3 months postoperatively had significant correlation with the size of retinal breaks (P < 0.005) and the number of laser photocoagulation spots (P < 0.05). Conclusion: Aqueous flare intensity after vitrectomy for RD decreased to a stable level at 3 months postoperatively but remained significantly higher than the normal level. The size of retinal breaks and the degree of surgical invasion were associated with the increase in aqueous flare.


European Journal of Ophthalmology | 2014

Intraocular Pressure Elevation after Vitrectomy for various Vitreoretinal Disorders

Yumi Hasegawa; Fumiki Okamoto; Yoshimi Sugiura; Yoshifumi Okamoto; Takahiro Hiraoka; Tetsuro Oshika

Purpose: To determine the incidence of and risk factors for intraocular pressure (IOP) elevation in the immediate postoperative period after vitrectomy for various vitreoretinal disorders. Methods: A prospective study was performed in 228 consecutive patients with various vitreoretinal disorders. The IOP was measured before surgery, at the end of surgery, and at 5 hours and 1 day after surgery using Tono-Pen XL®. The IOP at the end of surgery was adjusted to 15.0 ± 2.0 mm Hg. Results: Intraocular pressure elevation (>25 mm Hg) was found in 55 (24.1%) and 52 (22.8%) patients at 5 hours and 1 day postoperatively, respectively. The IOP at 5 hours was significantly lower in patients with macular hole (MH) than in those with diabetic macular edema, proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy, or rhegmatogenous retinal detachment (RD). The IOP at 1 day was significantly higher in patients with PDR and RD than in those with MH and epiretinal membrane. Multiple regression analysis revealed that IOP at 5 hours postoperatively had a significant correlation with the number of laser photocoagulation, preoperative IOP, combined cataract surgery, and 20-gauge vitrectomy. The IOP at 1 day postoperatively was significantly associated with these 4 parameters as well as the severity of postoperative vitreous hemorrhage and use of expanding gas tamponade. Conclusions: Intraocular pressure elevation was found in approximately one-quarter of cases within 1 day following vitrectomy. The risk factors for IOP elevation included number of laser photocoagulation, combined cataract surgery, severity of postoperative vitreous hemorrhage, and use of expanding gas tamponade.


Eye & Contact Lens-science and Clinical Practice | 2015

Topographic changes after excision surgery of primary pterygia and the effect of pterygium size on topograpic restoration.

Ayami Masuda; Keiichiro Minami; Yosai Mori; Yumi Hasegawa; Kazunori Miyata

Objective: To assess the effect of pterygium size on time-course change of corneal topography after excision surgery of primary pterygium. Methods: Retrospective case series included eyes that underwent excisions of primary pterygium. Pterygium size was graded according to the advancing edge position: less than one third of corneal diameter (grade 1), outside the pupil (grade 2), and within the pupillary area (grade 3). Time-course changes in corneal refractive power, astigmatism, and irregularity (surface regularity and asymmetry indices) in corneal topographies over 12 months postoperatively were compared between the pterygium size grades. Results: Pterygium excision was performed on 562 eyes, consisting of 119, 338, and 105 eyes with grades 1 to 3, respectively. Grade 1 did not change in corneal irregularity, and there was no difference between grades 1 and 2, except for corneal astigmatism at 6 months. Grade 3 showed significantly higher corneal refractive power and irregularity than grade 1 until 3 and 6 months, respectively, whereas corneal astigmatism was higher over 12 months. Conclusions: Topographic changes after primary pterygium excision were associated with pterygium size. Pterygium advancing over the pupillary area required 6 to 12 months for corneal topography restoration, resulting in slow recovery of visual acuity.


Journal of Cataract and Refractive Surgery | 2013

Effect of preoperative corneal astigmatism orientation on results with a toric intraocular lens

Yumi Hasegawa; Fumiki Okamoto; Shinichiro Nakano; Takahiro Hiraoka; Tetsuro Oshika

Purpose To compare the Acrysof IQ toric intraocular lens (IOL) and the Acrysof IQ aspheric nontoric IOL and evaluate the effect of preoperative corneal astigmatism orientation on results. Setting Department of Ophthalmology, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan. Design Comparative case series. Methods This retrospective chart review comprised patients with cataract and preoperative corneal astigmatism between 1.0 diopter (D) and 2.5 D having toric IOL (toric group) or aspheric nontoric IOL (nontoric group) implantation. Eyes were grouped depending on the preoperative axis of corneal astigmatism; that is, with the rule (WTR), against the rule (ATR), and oblique. Preoperative and postoperative analyses included uncorrected (UDVA) and corrected (CDVA) distance visual acuities and cylindrical power preoperatively and 3 months postoperatively. Results The postoperative CDVA was not significantly different between the 2 IOLs; however, the postoperative UDVA was significantly better in the toric group than in the nontoric group (P<.0001). The postoperative residual cylindrical power was significantly smaller in the toric group (P<.0001). In eyes with ATR and oblique astigmatism, the mean postoperative UDVA was significantly better in the toric group, whereas there were no differences between the 2 groups in patients with WTR astigmatism. Conclusions There was significant improvement in postoperative cylinder and UDVA with toric IOLs compared with nontoric IOLs. With a superior corneal incision, the benefits of astigmatism correction with the toric IOL were more significant in patients with ATR and oblique astigmatism than in those with WTR astigmatism. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.


American Journal of Ophthalmology | 2011

Ophthalmodynamometric pressure in eyes with proliferative diabetic retinopathy measured during pars plana vitrectomy.

Yoshimi Sugiura; Fumiki Okamoto; Yoshifumi Okamoto; Yumi Hasegawa; Takahiro Hiraoka; Tetsuro Oshika

PURPOSE To measure ophthalmodynamometric pressure (ODP) during vitrectomy in patients with proliferative diabetic retinopathy (PDR). DESIGN Prospective, interventional, consecutive case series. METHODS This study included 75 eyes of 75 patients undergoing vitrectomy for PDR. After core vitrectomy, the intraocular pressure was gradually raised using a vented-gas forced-infusion system (VGFI), and the optic nerve head was continuously monitored through a planoconvex contact lens. When the central retinal artery or its branches on the optic nerve head showed pulsations, the pressure was recorded as ODP. Diastolic blood pressure (DBP) and systolic blood pressure (SBP) were measured at the time of ODP measurement. Multiple regression analysis was performed to investigate the relationship between ODP and various explanatory variables: DBP, SBP, age, gender, body mass index, presence of hypertension, serum hemoglobin A1c, serum total cholesterol, fasting plasma glucose, presence of rubeosis iridis, and severity of PDR. RESULTS ODP was 63.6 ± 11.5 mm Hg (range 15.5-84.4 mm Hg). The ODP significantly correlated with DBP (r=0.570, P<.0001) and the mean arterial blood pressure (r=0.522, P<.0001), but not with SBP (r=0.121, P=.303). Multiple regression analysis revealed that ODP had a significant correlation with DBP (P<.0001), presence of rubeosis iridis (P<.0001), and severity of PDR (P=.046). CONCLUSIONS We measured ODP using VGFI during vitrectomy in patients with PDR. The ODP was significantly associated with DBP. The ODP was lower in patients with rubeosis iridis and severe PDR.


Clinical Ophthalmology | 2016

Risk factors for corneal endothelial cell loss by cataract surgery in eyes with pseudoexfoliation syndrome.

Yumi Hasegawa; Yosai Mori; Toshihiro Sakisaka; Keiichiro Minami; Kazunori Miyata; Tetsuro Oshika

Purpose The aim of this study was to investigate the factors associated with decreases in corneal endothelial cell density (ECD) resulting from cataract surgery in eyes with pseudoexfoliation syndrome (PEX). Methods The clinical records of 78 eyes of 78 patients with PEX who had undergone cataract surgery were reviewed. ECD was measured preoperatively and at 3 months postoperatively with specular microscopy. Multiple regression analysis was used to assess the factors that were significantly related to the rate of ECD loss. Explanatory variables included age, preoperative ECD, pupil diameter, cataract grade, concomitance of glaucoma or diabetes mellitus, preoperative anterior chamber depth, surgery time, total time and power of ultrasound, performance of intraoperative pupillary enlargement manipulation, and postoperative aqueous flare intensity at 1 week and 1 month. Results ECD before and after surgery was 2,464±337 cells/mm2 and 2,400±347 cells/mm2, respectively, with an ECD loss rate of 2.6%±5.1% (mean ± SD). Multiple regression analysis revealed that ECD loss was significantly associated with the cataract grade (P=0.019) and preoperative anterior chamber depth (P=0.023). Conclusion With modern small incision cataract surgery, the ECD loss varied with surgical invasions due to severe cataract and shallow anterior chamber, and the presence of PEX was least affected.


PLOS ONE | 2018

Effects of astigmatic defocus on binocular contrast sensitivity

Yumi Hasegawa; Takahiro Hiraoka; Shinichiro Nakano; Fumiki Okamoto; Tetsuro Oshika

Purpose To determine the effects of astigmatism on contrast sensitivity (CS). Methods Eighteen normal volunteers (30.5 ± 6.0 [mean ± SD] years) were recruited. After correcting each refractive error by spectacles, against-the-rule (ATR) or with-the-rule (WTR) astigmatism of +1.00, +2.00 and +3.00 D was intentionally produced in both eyes, and then binocular CS was measured. The cylindrical addition of different powers (+1.00–+3.00 D) was compensated with spherical lenses so that the spherical equivalent refraction became zero in each eye. Subsequently, the above cylindrical addition was monocularly induced, and binocular CS was measured again. The relation between CS and astigmatic power, axis, and monocular or binocular astigmatism was investigated. Results With binocular ATR and WTR astigmatism, increases in astigmatic power significantly correlated with decreases in the area under the log contrast sensitivity function (AULCSF). With monocular astigmatic defocus, astigmatic power addition did not affect AULCSF. With binocular astigmatic defocus of high-power (+2.00 and +3.00 D), ATR astigmatism deteriorated AULCSF more than WTR astigmatism. In a comparison between binocular and monocular astigmatic defocus, CS was significantly worse with binocular astigmatic defocus than with monocular astigmatic defocus at higher spatial frequencies regardless of astigmatic power. Conclusions Binocular astigmatic defocus deteriorates CS depending on the amount of astigmatic power. ATR astigmatism reduces CS more than WTR astigmatism dose. In addition, binocular astigmatic defocus affects CS more severely than monocular astigmatic defocus especially at high spatial frequencies.


Japanese Journal of Ophthalmology | 2012

Intraocular pressure elevation in the early postoperative period after vitrectomy for rhegmatogenous retinal detachment

Yumi Hasegawa; Fumiki Okamoto; Yoshimi Sugiura; Yoshifumi Okamoto; Takahiro Hiraoka; Tetsuro Oshika


Investigative Ophthalmology & Visual Science | 2012

Effect Of Monocularly And Binocularly Induced Astigmatic Blur On Stereopsis

Shinichiro Nakano; Takahiro Hiraoka; Yumi Hasegawa; Tetsuro Oshika


Investigative Ophthalmology & Visual Science | 2016

Effects of Astigmatic on Contrast Sensitivity assessed with Multiple Measurement Charts

Chie Yukawa; Yumi Hasegawa; Takahiro Hiraoka; Tetsuro Oshika

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