Transient Myopia Research Articles

A review of glycaemic changes on vision in phakic, aphakic and pseudophakic people with diabetes

Background: One of the leading causes of preventable blindness is cataract affecting approximately 18 million people worldwide. Twenty per cent of cataract operations worldwide are performed on people with diabetes mellitus (PDM).Aim: The aim of this review article is to analyse the scientific literature relating to visual changes associated with diabetes mellitus (DM) in pseudophakic, aphakic and phakic people, and to discuss the consequences of these changes for optometrists.Method: A literature search was conducted on PubMed, the University of KwaZulu-Natal Libraries and Google Scholar databases from August 2017 to August 2018.Results: Acute and chronic hyperglycaemia in DM causes myopia in phakic PDM, whilst in aphakic PDM it causes a hyperopic shift in refraction. It has been reported that contrast sensitivity and visual acuity are affected by changes in blood glucose. People with DM have increased central corneal thickness as compared to non-diabetics, whilst only the posterior corneal curvature is affected by hyperglycaemia in PDM. No evidence exists on the effects of glycaemic changes in pseudophakes.Conclusion: It should be noted that high blood glucose level (BGL) induces transient myopia and hyperopia in chronic phakic PDM and aphakic PDM, respectively. All refractive procedures, including prescription of spectacles, corneal refractive procedures and lens extraction, should be deferred until normalisation of BGL in phakic and pseudophakic PDM, as higher sugar levels affect corneal curvature and thickness and overall vision.

Use of Topical 0.01% Atropine for Controlling Near Work-Induced Transient Myopia: A Randomized, Double-Masked, Placebo-Controlled Study.

Purpose: To investigate the efficacy and safety of topical low-concentration (0.01%) atropine for controlling near work-induced transient myopia (NITM) in a young Chinese population. Methods: This was a randomized, double-blinded, placebo-controlled study. The participants were randomly divided into the 0.5% hydroxypropyl-methylcellulose-treated group (control group) or 0.01% atropine-treated group (study group). Participants' pulse rate, respiration rate, intraocular pressure, pupil diameter, and magnitude of initial NITM were evaluated at baseline and on day 7 and 14 during treatment. In addition, ocular discomfort and adverse effects were recorded. Results: Of the initial 176 participants, 145 (82.4%) completed the 14-day treatment and all evaluations. At baseline, no difference in the magnitude of initial NITM was observed between the control and study groups (P = 0.826). However, the magnitude of initial NITM of the study group was significantly lower at both day 7 (-0.11 ± 0.227 D) and day 14 (0.076 ± 0.183 D) after treatment initiation, compared with the magnitude of initial NITM in the control group (P < 0.001). No serious complications were observed. However, significantly larger pupil diameters were noted on day 7 and 14 in the study group than in the control group (P < 0.001). Conclusions: We speculate that daily topical 0.01% atropine application effectively reduced the magnitude of initial NITM, without any serious complications. The minimal pupil dilation induced by the treatment was acceptable. Low-concentration atropine may be useful in clinical settings as treatment for young patients with NITM.

Angiographic features of drug-induced bilateral angle closure and transient myopia with Ciliochoroidal effusion

BackgroundTo report five cases of acute drug-induced angle closure and transient myopia with ciliochoroidal effusion and to analyze angiographic findings of these cases.MethodsThis study is an observational case series. Five patients with acute drug-induced angle closure and transient myopia with ciliochoroidal effusion were examined by fluorescein angiography, indocyanine green angiography (ICGA) and ultrasound biomicroscopy (UBM).ResultsFive patients presented with bilateral visual loss and ocular pain after intake of topiramate, methazolamide, phendimetrazine tartrate or mefenamic acid. All patients showed elevated intraocular pressure (IOP) with shallow anterior chamber and myopic shift from − 0.5 to − 17.0 diopters (D). UBM showed ciliochoroidal effusions with diffuse thickening of the ciliary body in all cases. Rapid normalization of IOP and decrease of myopic shift occurred in all patients after discontinuing the suspected drugs. We classified the ICGA findings into 2 major signs (hypofluorescent dark spots, hyperfluorescent pinpoints) and 3 minor signs (diffuse choroidal hyperfluorescence, early hyperfluorescence of choroidal stromal vessel, and leakage and dilated retinal vessels).ConclusionsThe pathogenesis of acute drug-induced angle closure and transient myopia with ciliochoroidal effusion may be idiosyncratic reaction of uveal tissue to systemic drugs. Accumulation of extravascular fluid in the ciliochoroidal layer had a major role in the pathogenesis. ICGA could be a useful method to examine the pathophysiology of this condition by imaging of the choroidal layer.

Non-prescription cold and flu medication-induced transient myopia with uveal effusion: case report

BackgroundTo report a case of non-prescription cold and flu medication-induced transient myopia with uveal effusion.Case presentationBilateral high intraocular pressure, shallow anterior chambers, uveal effusion, and a myopic shift were encountered in a 39-year-old Chinese male 1 night after taking a non-prescription flu medicine three times than the recommended dose. Ultrasound biomicroscopy (UBM) showed bilateral ciliochoroidal effusions, disappearance of the ciliary sulcus, closure of the angle of the anterior chamber, and anterior displacement of the lens-iris diaphragm. Treatment with aqueous suppressants was given. Within a week, the uncorrected vision restored, and the myopia had disappeared. UBM revealed major resolution of the ciliochoroidal effusions in both eyes, deepening of the anterior chamber, return of the lens-iris diaphragm to a more posterior position.ConclusionsOverdose of non-prescription cold and flu medication may cause bilateral uveal effusions inducing acute angle-closure glaucoma and acute myopia.

CEFALIUM-INDUCED BILATERAL TRANSIENT MYOPIA, RETINAL FOLDS, AND FOCAL CHOROIDAL DELAY

To describe a case of acute bilateral transient myopia, retinal folds, and island of choroidal delay associated with oral administration of Cefalium, a medication commonly prescribed in Brazil for migraine that combines acetaminophen 500 mg, caffeine 40 mg, dihydroergotamine mesylate 1 mg, and metoclopramide hydrochloride 10 mg. A 21-year-old woman with bilateral blurred vision 1 day after the use of Cefalium. The main outcomes measures were BCVA, ocular fundus, ocular coherence tomography, and angiography findings. The patient developed bilateral myopia, retinal folds, and focus choroidal delay 1 day after the administration of oral cefalium. Ocular fundus examination and ocular coherence tomography revealed retinal folds in the internal surface of the retina. Angiography showed focus areas of hypofluorescence in both eyes. Seven days after Cefalium was suspended, all clinical symptoms had resolved, with full recovery from the abnormal findings on ocular fundus, ocular coherence tomography, and angiography. This is the first report that identified and described bilateral transient myopia, retinal folds, and focus choroidal delay secondary the use of Cefalium.

ISMP Adverse Drug Reactions: Sildenafil-Induced Erythema Multiforme Acute Liver Injury Due to Febuxostat Intravenous Acetaminophen-Induced Acute Hepatotoxicity Acute Transient Myopia Induced by Zanamivir Lidocaine-Induced Hoigne Syndrome.

The purpose of this feature is to heighten awareness of specific adverse drug reactions (ADRs), discuss methods of prevention, and promote reporting of ADRs to the US Food and Drug Administration's (FDA's) MedWatch program (800-FDA-1088). If you have reported an interesting, preventable ADR to MedWatch, please consider sharing the account with our readers. Write to Dr. Mancano at ISMP, 200 Lakeside Drive, Suite 200, Horsham, PA 19044 (phone: 215-707-4936; e-mail: mmancano@temple.edu). Your report will be published anonymously unless otherwise requested. This feature is provided by the Institute for Safe Medication Practices (ISMP) in cooperation with the FDA's MedWatch program and Temple University School of Pharmacy. ISMP is an FDA MedWatch partner.

English

Acetazolamide is a carbonic anhydrase inhibitor which is on World Health Organization&rsquo;s list of essential medicines, a list of most important medications needed in a basic health system. The ocular effects of acetazolamide was studied in 30 normotensive volunteers. Each volunteer received a loading dose of 500 mg at 0700 h followed by a maintenance dose of 250 mg at 1300 and 1800 h, respectively on day one. From day two to day five, the volunteers received 250 mg acetazolamide thrice daily at the established time intervals. Each volunteer served as his or her own control. Ocular effects of the drug were assessed on the following visual functions; pupil diameter, near point of convergence, visual acuity, amplitude of accommodation, accommodation/convergence accommodation ratio and the phoria status. Results showed that the pupil diameter and near point of convergence increased while the amplitude of accommodation and the accommodation/convergence accommodation ratio decreased. The phoria tended towards exophoria. The aggregate effect on the volunteers was convergence insufficiency with the accompanying asthenopic symptoms, transient myopia and photophobia. Key words: Acetazolamide, asthenopic, symptoms, convergence, insufficiency.

Near work‐induced transient myopia in Indian subjects

PurposeThe aim was to determine the characteristics of near work‐induced transient myopia (NITM) in asymptomatic Indian subjects and the influence of target size and contrast.MethodsTwo studies were conducted: First, 24 myopes and 24 emmetropes viewed four targets (N8 and N12 with 50 and 90 per cent contrasts) placed at 0.2-m for five minutes. The refractive status was assessed objectively, before and after carrying out the near task, with the Grand Seiko WAM‐5500 open‐field autorefractor under monocular viewing conditions. Second, a different group of 24 myopes and 24 emmetropes viewed a N12 target with 90 per cent contrast for 60-minutes with pre‐ and post‐refractive state measurements repeated as above. NITM was defined as the difference between pre‐task and post‐task distance refraction.ResultsIn the first study, myopes demonstrated an initial post‐task myopic shift of 0.21 D, whereas emmetropes demonstrated a small hyperopic shift of 0.07 D (p < 0.001). The myopes demonstrated a decay time constant of 6.07-seconds. There was no effect of target size or contrast on the magnitude of the NITM or the decay time constant (p > 0.05). In the second study, myopes showed a NITM of 0.31 D, which was significantly greater than emmetropes (p < 0.001). The myopes demonstrated a decay time constant of 8.16-seconds.ConclusionThe magnitude of the NITM was higher in myopes compared to emmetropes for both five minute and 60-minute viewing time. The NITM decayed slightly faster than that found in previous literature for some other ethnic groups. Potential reasons for these findings are discussed.

Aripiprazole Induced Acute Transient Bilateral Myopia: A Case Report.

Aripiprazole is an atypical antipsychotic drug. Acute transient myopia is a rare response to systemic medication. Unspecified ocular side effects of aripiprazole have rarely been reported. To the best of our knowledge, only 3 cases of aripiprazole induced myopia and diplopia have been reported in the literature. The aim of this article is to present a case of aripiprazole-induced acute transient myopia. A 30 year-old woman underwent treatment for 5 days with aripiprazole and presented with bilateral painless blurred vision. The patient's uncorrected visual acuity was 2/10 in both eyes and her best corrected visual acuity was 10/10 in both eyes with a refractive error of -3.00 diopters using a standard Snellen chart. Adding 2 mgs of biperiden a day to her treatment regimen decreased her blurred vision symptoms. After discontinuation of aripiprazole treatment and cross-switching to Paliperidon palmitate (75 mg/month) her blurred vision completely resolved. The same side effect did not re-occur when checked on her 6-month follow up. Ophthalmologists as well as psychiatrists must be aware of this myopic shift and should also ask these patients about medicine usage, especially aripiprazole. Ophthalmologists should consult the prescribing psychiatrist and stop the drug immediately to reverse this temporary condition.

Transient Drug-Induced Myopia

Myopia (nearsightedness) is a refractive error, a condition in which the cornea and lens of the nonaccommoding eye have too much plus power for the length of eye. As a result, images of distant objects are focused in front of the retina and thus appear blurred. Transient drug-induced myopia is a myopia induced by a drug as a transient side effect. Several case reports of transient drug-induced myopia have been reported. These cases have been associated with secondary angle closure glaucoma and other ocular conditions such as choroidal detachment, maculopathy, retinal folds. Drugs known to produce this effect include sulfa drugs and other medications. The possible mechanism is thought to be an allergic reaction to the drug. Both ciliary muscle contraction and ciliary body edema may play role in the pathomechanism. Differential diagnosis is made with a number of conditions, either ocular in origin or associated with an underlying systemic cause. Discontinuation of medications leads to complete resolution of the anatomic shift. *Corresponding author: Kaimbo DKW, MD, PhD, Department of Ophthalmology and Biophysics, University of Kinshasa, Tel: +243998238928, E-mail: dieudonne_kaimbo@yahoo.com Kaimbo DKW* Myopia is the most common eye disease and is one of the leading causes of vision impairment worldwide [1,2]. Prevalence of myopia is significantly different among racial groups, although its worldwide prevalence is approximately 30% (3%– 84%) [3]. The highest prevalence is found in East Asia, such as mainland China [3]. The prevalence of myopia in the US population was estimated in the early 1970s to be 25% in persons aged 12 to 54 years [4]. A recent meta-analysis of population-based studies found a prevalence of 25% in persons over age 40 [5]. Myopia (nearsightedness) is a refractive error, a condition in which the cornea and lens of the nonaccommoding eye have too much plus power for the length of eye. As a result, images of distant objects are focused in front of the retina and thus appear blurred. Citation: Kaimbo DKW (2014) Transient Drug-Induced Myopia. SAJ Case Rep 1(1): 105. doi: 10.18875/23757043.1.105 Volume 1 | Issue 1 Volume 1 | Issue 1 Research Article Open Access SAJ Case Reports www.scholarena.com Myopia has been recognized as a distinct visual disability for millennia and has been known for more than 2000 years and was first described by the ancient Greeks [6,7]. It was probably the ancient Greeks who coined the term, using the roots myein (to close) and ops (eye) to characterize those individuals who narrow their eyelids to improve distance visual acuity, the pinhole effect. The focus of distant parallel rays of light falls anterior to the retinal plane and produces a blurred image in myopia. This situation can arise because either the primary refractive components are too powerful or the globe is too long. Thus, myopia can be due to increased corneal or lenticular curvature, or an increase in the lens index of refraction, as occurs with the development of nuclear sclerosis. More commonly, myopia is the result of axial elongation of the posterior segment of the eye. Transient drug-induced myopia is a myopia induced by a drug as a transient side effect. A side effect (adverse drug reaction) is basically an unintended, unwanted occurrence that results from taking a drug. An adverse drug reaction is an expression that describes harm associated with the use of given medication at a normal dosage during normal use. Adverse drug reactions may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs [8]. All drugs that come in the market may cause side effects, where many are minor and few are serious. Article history: Received: 26 June 2014 Accepted: 12 August 2014 Published: 14 August 2014 ISSN: 2375-7043

Oseltamivir (Tamiflu)-induced bilateral acute angle closure glaucoma and transient myopia

A 27-year-old woman developed bilateral acute angle closure glaucoma (AACG) and transient myopia after taking oseltamivir for four days. On the fourth day, she received systemic and topical intraocular pressure (IOP)-lowering agents, and IOP decreased in both eyes. However, her visual acuity was unchanged. A myopic shift of -5.25 D OD and -5.0 D OS was estimated to have occurred in the acute phase. A-scan ultrasonography and Pentacam showed markedly shallow anterior chambers and increased lens thickness. Ultrasound biomicroscopy revealed an annular ciliochoroidal effusion with forward displacement of the lens-iris diaphragm. Ciliochoroidal effusion and transient myopia were resolved after discontinuation of oseltamivir.

Indapamide-induced transient myopia with supraciliary effusion: case report

BackgroundIngestion of sulphonamide-derived drugs has been reported to possibly have ocular side-effects. Authors aimed to present a rare case of indapamide-induced transient myopia with ciliary body edema and supraciliary effusion.Case presentationA 39 years old caucasian female patient presented at the Department of Neurology with headache and sudden bilateral loss of distant vision. Neurological assessment and cranial CT scans were unremarkable. For her hypertension, twice a day bisoprolol 2.5 mg and once a day indapamide 1.5 mg tablets were prescribed several days before. At her presenting, ophthalmic findings were as follows: visual acuity 0.08-7.25Dsph = 1.0 and 0.06-7.25Dsph = 1.0; IOP 25 mmHg and 24 mmHg, anterior chamber depth (ACD) 2.32 mm and 2.49 mm, lens thickness (L) 4.02 mm and 4.09 mm in the right and the left eye, respectively. By means of ultrasound biomicroscopy (UBM), thickened (720 / 700 micron) and detached ciliary body, its forward movement (ciliary body-cornea angle 108′ / 114′) and forward rotated ciliary processes were seen. Angle opening distance (AOD500) were 300 / 314 microns. By the following days, the myopia gradually diminished, and a week after her first symptoms, her uncorrected visual acuity was 1.0 in both eyes, IOP 13 mmHg and 17 mmHg, ACD 3.68 mm and 3.66 mm, L 3.78 mm and 3.81 mm in the right and the left eye, respectively. Ciliary body edema and detachment disappeared (ciliary body thickness 225 / 230 micron), both of the ciliary body-cornea angle 134′ / 140′ and the AOD500 (650 / 640 microns) increased. At this point, the patient admitted that she had stopped taking indapamide two days before.ConclusionsOur case report is the third one in the literature to present indapamide-induced transient myopia, and the first to employ UBM for describing the characteristics of this rare condition. According to the findings, authors suggest that both ciliary muscle contraction and ciliary body edema may play role in the pathomechanism. UBM seems to be a useful tool in the differential diagnosis of acute myopia. Further, authors wish to draw attention to one of the potential adverse effects of this drug which was not listed by its package insert.

Nearwork‐induced transient myopia (NITM) in anisometropia

To assess the magnitude of nearwork-induced transient myopia (NITM) under binocular viewing conditions separately in each eye of individuals with mild to moderate anisometropia to determine the relationship between NITM and their interocular refractive error. Forty-three children and young adults with anisometropia [cycloplegic spherical equivalent (SE) difference >1.00 D] were tested (ages 9-28 years). NITM was measured with binocular viewing separately in each eye after binocularly performing a sustained near task (5 D) for 5 min incorporating a cognitive demand using an open-field, infrared autorefractor (Grand-Seiko, WAM-5500). Data were averaged over 10 s bins for 3 min in each eye. Initial NITM, its decay time (DT), and its decay area (DA) were determined. A-scan ultrasound ocular biometry was also performed to determine the axial length of each eye. The more myopic eye exhibited increased initial NITM, DT, and DA as compared to the less myopic eye (0.21 ± 0.16 D vs 0.15 ± 0.13 D, p = 0.026; 108.4 ± 64.3 secs vs 87.0 ± 65.2 secs, p = 0.04; and 17.6 ± 18.7 D*secs vs 12.3 ± 15.7 D*secs, p = 0.064), respectively. The difference in DA and the difference in SE between the more versus less myopic eye were significantly correlated (r = 0.31, p = 0.044). Furthermore, 63% (27/43), 56% (24/43), and 70% (30/43) of the more myopic eyes exhibited increased initial NITM, longer DT, and larger DA, respectively, than found in the less myopic eye. In approximately two-thirds of the anisometropic individuals, the initial NITM and its decay area were significantly increased in the more myopic eye as compared to the less myopic eye. NITM may play an important role in the development of interocular differences in myopia, although a causal relationship is yet to be established. Furthermore, the findings have potentially important implications regarding accommodative control and interocular accommodative responsitivity in anisometropia, in particular for anisomyopia.

Nearwork-Induced Transient Myopia and Parental Refractive Error

To investigate the relationship between parental refractive error and the nearwork-induced transient myopia (NITM) characteristics of their children. Three hundred sixty children (173 boys and 187 girls) aged 6 to 17 years were tested. Initial NITM and its decay time (DT) were assessed objectively (WAM-5500, Grand-Seiko) immediately after binocularly viewing and performing a sustained near task (5 diopters [D]) for 5 minutes, incorporating a cognitive demand with full distance refractive correction in place. The NITM was classified into three categories: low (< 0.15 D), moderate (0.15 to 0.30 D), or high (≥0.30 D), whereas its decay was classified into two categories, namely, complete or incomplete. In addition, the children were divided into three groups based on the number of myopic parents (none, one, or two) and into four groups based on the level of parental myopia (no, low, moderate, or high). Neither paternal nor maternal refractive error was associated with either their children's initial NITM magnitude or its DT in the myopic, emmetropic, or hyperopic groups or the combined group. No significant differences (p > 0.05) in the NITM magnitude, DT, or decay time constant were found as related to the number of myopic parents or level of parental myopia. Multiple odds ratio for incomplete decay of NITM did not change significantly (p > 0.05) with either an increase in number of myopic parents or level of parental myopia. There was no association between parental refractive error and their children's NITM characteristics. This suggests a primary environmental basis for the NITM characteristics in the children.

Peripheral Serous Pigment Epithelial Detachment and Retinal Detachment Presumably Associated with Hydrochlorothiazide Use

Sulfa-derivatives have been associated with acute transient myopia, angle closure glaucoma (ACG), and ciliochoroidal effusion syndrome (CCES) but not with pigment epithelial detachment (PED) or serous retinal detachment (SRD) [1], [2], [3], [4]. We report a case with features of CCES as well as a peripheral serous PED (SPED) and SRD which developed while taking hydrochlorothiazide, a sulfa-derivative.

Children’s Accommodation During Reading of Chinese and English Texts

Inaccurate accommodation during nearwork and subsequent accommodative hysteresis may influence myopia development. Myopia is highly prevalent in Singapore; an untested theory is that Chinese children are prone to these accommodation characteristics. We measured the accuracy of accommodation responses during and nearwork-induced transient myopia (NITM) after periods spent reading Chinese and English texts. Refractions of 40 emmetropic and 43 myopic children were measured with a free-space autorefractor for four reading tasks of 10-minute durations: Chinese (SimSun, 10.5 points) and English (Times New Roman, 12 points) texts at 25 cm and 33 cm. Accuracy was obtained by subtracting accommodation response from accommodation demand. Nearwork-induced transient myopia was obtained by subtracting pretask distance refraction from posttask refraction, and regression was determined as the time for the posttask refraction to return to pretask levels. There were significant, but small, effects of text type (Chinese, 0.97 ± 0.32 diopters [D] vs. English, 1.00 ± 0.37 D; F1,1230 = 7.24, p = 0.007) and reading distance (33 cm, 1.01 ± 0.30 D vs. 25 cm, 0.97 ± 0.39 D; F1,1230 = 7.74, p = 0.005) on accommodation accuracy across all participants. Accuracy was similar for emmetropic and myopic children across all reading tasks. Neither text type nor reading distance had significant effects on NITM or its regression. Myopes had greater NITM (by 0.07 D) (F1,81 = 5.05, p = 0.03) that took longer (by 50s) (F1,81 = 31.08, p < 0.01) to dissipate. Reading Chinese text caused smaller accommodative lags than reading English text, but the small differences were not clinically significant. Myopic children had significantly greater NITM and longer regression than emmetropic children for both texts. Whether differences in NITM are a cause or consequence of myopia cannot be answered from this study.

Neck pain brought into focus

A time honored dictum states that the eyes "lead the body", i.e., that the body typically adjusts its position to compensate for an impoverished retinal image (e.g., as due to optical blur, and/or inappropriately sized visual target). But only moderate or low level of evidence exists in support of this view. Inconclusive evidence does not, however, equal negative evidence. The accommodation/vergence system does exhibit signs of overload in contemporary working life, including eye discomfort, transient myopia, altered pattern of eye-lens oscillations, and associated phoria. Accommodation/vergence overload, caused by non-ergonomic near work, may also emerge as quickly as within one regular workday. Long-term musculoskeletal consequences of high accommodation/vergence demands have nevertheless not yet been studied in any detail. A research agenda which aims to provide multi-scientific evidence for eye-neck/shoulder interactions with public health implications and which also, in addition, study the eye-neck/shoulder mechanisms and elucidates the operating characteristics, should consequently be highly warranted. This new knowledge would be useful for physiotherapists, ergonomists and opticians, who in their profession treat patients experiencing vision- and musculoskeletal disorders. If both visual and the musculoskeletal aspects are given full and equal weight in the design and evaluation of work places, it is predicted to lead to an improved quality of life for the individual worker, and an enhanced productivity for the employer.

Accommodative response and nearwork-induced transient myopia induced by simplified and traditional Chinese characters

Background Epidemiologic studies found that the incidence of myopia is higher in Hong Kong and Taiwan regions of China than that of the mainland.So whether the general reading words with traditional Chinese characters and simplified characters is associated with myopia deserves attention.Objective This study was to test the accommodative responses and the regression levels of nearwork-induced transient myopia (NITM) induced by traditional complex Chinese characters and modern simplified ones in the same size,and to explore the differences and inherent relationship of the accommodative regulations based on the structures of the two types of Chinese character in causing reading triggered myopia.Methods Twenty two volunteers aged 24-29 years were included in this study with informed consent.The corrected vision of both eyes from each subject was ≥ 1.0 with a mean spherical equivalence of (-1.86±2.34)D.Accommodative response was tested with 4 different reading texts using the rapid sequence visual presenting model with the GRAND SEIKO-WV5500 infrared autorefractor,and this procedure was performed after full correction of refractive error.An initial test of looking at a certain distance was performed (as baseline),and then the subjects read intensively at the targets for 10 minutes at 33 cm to calculate the accommodative responses.After a 10 second pause,the ocular refractive status was obtained exactly at 15 seconds,20 seconds.The one-way ANOVA method was used to determine the effects of the different font types and sizes on the adjustive responses and the causation of NITM.Results Accommodative response induced by simplified and traditional Chinese characters showed an accommodative lag of (1.11 ±0.38),(0.95 ±0.43),(1.18 ±0.33) and (1.06±0.28) D,showing a significant difference among the 9 pt and 12 pt simplified and traditional Chinese characters (F =1.62,P =0.19),and significantly different accommodative lag values between 12 pt simplified characters and 9 pt traditional characters was found (t =5.56,P =0.02).NITM induced by the four different targets were (-0.45 ±0.45),(-0.47 ±0.46),(0.45 ±0.82) and (-0.46±0.78) D in the 4 types of characters,without a significant difference among them (F=0.01,P =0.99).Conclusions Near-distance reading causes accommodative lag regardless of the type of reading texts.The target demonstrated stimuli spatial frequency and font size play an impact on accommodative responses.NITM appears when one reads simplified or traditional Chinese for 10 minutes.The accommodative lag and NITM trend might be responsible for the onset or regression of myopia,yet it is not supportive for the hypothesis that reading traditional Chinese causes more strain since there is no difference between the two. Key words: Myopia; Accommodative response; Nearwork-induced transient myopia; Chinese character/simplified, traditional

Baseline Characteristics of Nearwork-Induced Transient Myopia

The purpose of the present study was to describe the baseline refractive and nearwork-induced transient myopia (NITM) characteristics of the Beijing Myopia Progression Study, a 3-year cohort study, that has three overall specific aims: to investigate the natural history of NITM in schoolchildren living in the inner city of Beijing aged between 7 and 17 years; to investigate the possible relation between NITM and permanent myopia; and to determine the possible associations with NITM (eg, parental history). Three hundred eighty-six students (187 males and 199 females) were enrolled. The mean ages were 8.4 ± 1.1 years and 14.2 ± 1.6 years for the primary school and secondary school students, respectively. Baseline refractive aspects were determined clinically. Initial NITM and its decay were assessed objectively immediately after binocularly viewing and performing a sustained near task (5 minutes; 5 diopters [D]), incorporating a cognitive demand with full distance refractive correction in place. Initial NITM (mean ± SD) / decay time (median, first quartile, and third quartile) was 0.18 ± 0.16 D / 50 (20, 90) seconds, 0.09 ± 0.13 D / 30 (10, 40) seconds, and 0.10 ± 0.19 D / 20 (10, 40) seconds among the myopic, emmetropic, and hyperopic students, respectively, for the combined school levels. Initial NITM and decay time were significantly larger/longer in the myopic versus the other two refractive groups. The present findings demonstrate that in a large sample of school-aged children with myopia, the initial NITM magnitude was significantly larger and the decay duration was significantly longer than that observed in age-matched children with either emmetropia or hyperopia. Follow-up for the next 3 years will provide insight into the possible role of NITM in the development of permanent myopia.

The effect of simplified and traditional chinese character on accommodative reponses in myopes and emmtropes

AbstractPurpose This study investigated the effect of simplified and traditional chinese character on accommodative lag, accommodation microfluctuation, near work‐induced transient myopia (NITM) during the near task as well as the subsequent decay time. We aimed to analyze if the traditional Chinese character had the trend of inducing the myopia progress.Methods Young adults were classified into emmetropes and myopes . Two size (12pt,8pt) and two type (simplified and traditional chinese character) were used to give four different reading targets on computer screen. It was presented in random order at 25 cm and was read for 5min. For each target, accommodation response , accommodation microfluctuation NITM and its decay were measured using the free space Grand‐Seiko auto‐refractor.Results For myopic subjects, accommodation microfluctuation was greater for traditional chinese character 0.35±0.17 D than for simplified chinese character: 0.29 ±0.11 D, (p=0.017) ,NITM was larger for traditional chinese traditional character 0.61±0.34 D than for simplified chinese character 0.53±0.33 D,p=0.028, however there was no difference in emmetropic subjects. Myopes had larger accommodation microfluctuation 0.35±0.17 D than emmetrope 0.24±0.11 D p=0.02,myopes had greater NITM0.61±0.34 D than emmetropes 0.42±0.25 D P=0.013. For all targets, The accommodative lag of myopes is 0.74±0.32 D while the emmetropes 0.53±0.35 D P=0.000 ;The decay time for myopes was15.88±19.53 seconds while the emmetropes 9.04±12.62 seconds P=0.012.Conclusion The study showed that compare to the simplified Chinese character, the traditional chinese character had significant effect on myopic subjects, it may be more susceptible of inducing the myopia progress.