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To evaluate the differences in accommodative gain in response to different accommodative stimuli and determine the effects of pupil size, binocular viewing, and inherent eye refraction on accommodative gain.This study enrolled 47 healthy young adults (emmetropia: 21 eyes, myopia: 26 eyes). Refractive value and pupil size during accommodative stimulus were measured using an open-viewing type auto-refractor (Grand Seiko WAM-5500). The subject was continuously presented with six stimuli (0D, 1D, 2D, 3D, 4D, and 5D) in front of the eye. Measurements were performed under three conditions. Condition 1: Monocular status with complete occlusion of the non-viewing eye; Condition 2: Monocular status with occlusion of the non-viewing eye by translucent occluder; Condition 3: Binocular status.In the emmetropia group, there was no significant difference in accommodative gain between conditions 1 and 2 (The effects of pupil size and binocular viewing on accommodative gain differed between emmetropia and myopia.

The main aim of this study was to compare refraction measurements with and without cycloplegia from two refractors devices, (TRK-2P autorefractometer (TRK-2P) and wavefront-based refraction Visionix 130 (VX130)) in children and adolescents. This descriptive observational study included 20 myopic eyes and 40 hyperopic eyes measured in two different Spanish hospitals. Cycloplegia was carried out by three drops of cyclopentolate hydrochloride 1% (Colircusí cycloplegic, Alcon Healthcare S.A., Barcelona). The mean age of the myopia group was 12.40 ± 3.48 years; for the hyperopia group, the mean age was 7.37 ± 2.47 years. In the myopia group, autorefraction and wavefront-based refraction did not show clinically significant differences in any components between with and without cycloplegia. The hyperopia group showed statistical and clinically significant differences in sphere and SE components between relaxed and non-relaxed states of accommodation, although the cylindrical components were not clinically different. In this study, we considered a value of ≥0.50D as a clinically significant difference in refraction. Therefore, both devices were capable of obtaining accurate refractions without cyclopegia in myopia children, although they did not avoid instrument myopia and accommodation involved in hyperopia children. Moreover, both refractometers could be useful for astigmatism monitoring in children without the need for cycloplegic drops. This work was supported by the Red Temática de Investigación Cooperativa en Salud under Grant [OFTARED RD12/0034 and RD16/0008]; Multiopticas Grant.

This paper designs an artificial intelligence-based auxiliary analysis framework for the correlation between myopia and refractive factors in adolescents. First of all, the influencing factors of adolescents' myopia and the degree of influence of factors such as the refractive power of the eyes and the axis of the eyes on myopia were analyzed. Next, the correlation between myopia and eye refractive power was overviewed. Finally, an artificial intelligence framework is designed to assist in the analysis of the correlation between myopia and eye refraction.

Spot Vision Screener (SVS) can conduct refraction tests for both eyes within a short period. This study aims to evaluate the refraction and pupil diameters of 3-year- and 1-month-old Japanese children using SVS in regular medical checkup. We examined 2438 eyes of 1219 children (age: 3-year- and 1-month) in Fujieda (Shizuoka, Japan) to assess their refraction and pupil diameters and eye-position screening conducted by SVS. SVS successfully measured 1217 children (99.8%). Regarding the right eye refraction, the spherical power was +0.70 ± 0.55 D (median, +0.75 D), and the cylindrical power was −0.67 ± 0.49 D (median, −0.50 D). The pupil diameter of the right eyes was 5.57 ± 0.79 (median, 5.60) mm. we could obtain a large number of basic data for 3-year- and 1-month-old Japanese children. However, refraction and pupil diameter of children were not normally distributed, so careful handling of children’s basic data on the eye is necessary.

It is well known that human crystalline lens shape, dimensions and optical properties change throughout life and influence whole eye refraction. However, it is not clear if lens properties are associated with other ocular parameters. The purpose of the present study was to investigate the relationship of corneal and external globe dimensions with adult lens diameter (LD), lens thickness (LT) and lens power (LP) in order to determine if external factors influence lens properties. Postmortem human eyes (n = 66, age = 20-78 years) were obtained from the Ramayamma International Eye Bank, Hyderabad, India. Globe antero-posterior length (GAPL) and mean (average of horizontal and vertical) diameters of cornea (MCD) and globe (MGD) were measured using digital calipers. Eyes were dissected to produce ocular structures that contain the lens maintained in its accommodating framework, including intact zonules, ciliary body and sections of sclera. Specimens were mounted in a mechanical lens stretching system. LD, LT and LP were measured using high magnification retro-illumination photography, slit illumination photography and Scheiner principle-based optical system respectively in the unstretched (accommodated) state. Relationships between external globe and corneal dimensions and LD, LT or LP were assessed by multiple regression analysis. Age (0.012 ± 0.003 mm/year; p

The main reason for decreased vision in 25-30% of children is hereditary, congenital or acquired in an early reward...

The Doctoral Thesis was carried out at Riga Children’s Clinical University hospital and Rīga Stradiņs University, Faculty of Medicine, Department of Ophthalmology. Defence: at the public session of the Doctoral Council of Medicine on 25 September 2019 at 15.00 in the Hippocrates Lecture Theatre at Rīga Stradiņs University.

This case study examined the hypothesis that longer outdoor time results in normal vision and refractive status, using unique genetically informative kinships. The participants were the members of 29-year-old doubly exchanged monozygotic male twin pairs from Bogotá, Colombia, in South America. Comprehensive ophthalmological examinations, including uncorrected and corrected visual acuity, refraction and keratometry, and visual life history interviews were undertaken; all examinations were conducted by two ophthalmologists blind to the hypothesis, relatedness, and rearing status of the four participants. Normal uncorrected vision and refractive status were present in the two rural-raised, unrelated brothers, relative to their urban-raised counterparts. Uncorrected visual acuities were 20/160 and 20/200 for the city-raised twins and 20/20 and 20/30 for the country-raised twins. Premature birth, low birth weight, computer use, and reading time could not explain these differences. It was concluded that time spent outdoors appears to be a significant factor in the development of myopia, reinforcing extant findings via a novel experimental approach.

lntravitreal injection of substances dissolved in a vehicle solution is a common tool used to assess retinal function. We examined the effect of injection procedures (three groups) and vehicle solutions (four groups) on the development of form deprivation myopia (FDM) in juvenile tree shrews, mammals closely related to primates, starting at 24 days of visual experience (about 45 days of age). In seven groups (n = 7 per group), the myopia produced by monocular form deprivation (FD) was measured daily for 12 days during an 11-day treatment period. The FD eye was randomly selected; the contralateral eye served as an untreated control. The refractive state of both eyes was measured daily, starting just before FD began (day 1); axial component dimensions were measured on day 1 and after eleven days of treatment (day 12). Procedure groups: the myopia (treated eye - control eye refraction) in the FD group was the reference. The sham group only underwent brief daily anesthesia and opening of the conjunctiva to expose the sclera. The puncture group, in addition, had a pipette inserted daily into the vitreous. In four vehicle groups, 5 μL of vehicle was injected daily. The NaCl group received 0.85% NaCl. In the NaCl + ascorbic acid group, 1 mg/mL of ascorbic acid was added. The water group received sterile water. The water + ascorbic acid group received water with ascorbic acid (1 mg/mL). We found that the procedures associated with intravitreal injections (anesthesia, opening of the conjunctiva, and puncture of the sclera) did not significantly affect the development of FDM. However, injecting 5 μL of any of the four vehicle solutions slowed the development of FDM. NaCl had a small effect; myopia development in the last 6 days (-0.15 ± 0.08 D/day) was significantly less than in the FD group (-0.55 ± 0.06 D/day). NaCl + Ascorbic acid further slowed the development of FDM on several treatment days. H2O (-0.09 ± 0.05 D/day) and H2O + ascorbic acid (-0.08 ± 0.05 D/day) both almost completely blocked myopia development. The treated eye vitreous chamber elongation, compared with the control eye, in all groups was consistent with the amount of myopia. When FD continued (days 12-16) without injections in the water and water + ascorbic acid groups, the rate of myopia development quickly increased. Thus, it appears the vehicles affected retinal signaling rather than causing damage. The effect of water and water + ascorbic acid may be due to reduced osmolality or ionic concentration near the tip of the injection pipette. The effect of ascorbic acid, compared to NaCl alone, may be due to its reported dopaminergic activity.

Purpose: To evaluate the effects of age, race, and ethnicity on the optic nerve and peripapillary retina using spectral-domain optical coherence tomography (SD-OCT) three-dimensional (3D) volume scans in normal subjects. Methods: This is a cross-sectional study performed at a single institution in Boston. All patients received retinal nerve fiber layer (RNFL) scans and an optic nerve 3D volume scan. The SD-OCT software calculated peripapillary RNFL thickness, retinal thickness (RT), and retinal volume (RV). Custom-designed software calculated neuroretinal rim minimum distance band (MDB) thickness and area. Results: There were 272 normal subjects, including 175 whites, 40 blacks, 40 Asians, and 17 Hispanics. Rates of age-related decline were 2.3%, 2.0%, 1.7%, 3.3%, and 4.3% per decade for RNFL, RT, RV, MDB neuroretinal rim thickness, and MDB area, respectively. The RNFL was most affected by racial and ethnic variations, with Asians having thicker global, superior, and inferior RNFL, Hispanics having thicker inferior RNFL, and blacks having thinner temporal RNFL, compared to whites. For MDB thickness and area, Asians had smaller nasal values and blacks had smaller temporal values. Peripapillary RT and RV parameters were not influenced by race and ethnicity. Conclusions: All of the parameters exhibited age-related declines. RNFL, MDB thickness, and MDB area demonstrated racial and ethnic variations, while peripapillary RT and RV did not. Translational Relevance: This study demonstrates that both normal aging and ethnicity affect several novel 3D OCT parameters used to diagnose and monitor glaucoma (i.e., RT, RV, and MDB), and this should be factored in when making clinical decisions based on these parameters. © 2018 The Authors.

Адрес: 119991, г. Москва, ул. Трубецкая, д. 8, стр. 2; тел. 8(499)2484365; e-mail: kvv.doc@gmail.com. Сергеев Артем Рубенович – ассистент кафедры общественного здоровья и здравоохранения МПФ, ГБОУ ВПО Первый Московский государственный медицинский университет им. И.М. Сеченова Минздрава России. Адрес: 119991, г. Москва, ул. Трубецкая, д. 8, стр. 2; тел. 8(499) 2486024; e-mail: art.sergeev@mail.ru. Authors Golubeva Alla Prokophyevna – Doctor of Medical Science, Professor, Chair of Public Health, I. M. Sechenov First Moscow State Medical University. Address: 8-2, Trubetskaya Str., Moscow, 119991, Russia; Phone: 8 (499) 2486024; e-mail: apgolub@mail.ru. Kozlov Vasiliy Vladimirovich – Candidate of Medical Science, Associate Professor, Chair of Public Health, I. M. Sechenov First Moscow State Medical University. Address: 8-2, Trubetskaya Str., Moscow, 119991, Russia; Phone: 8 (499) 2484365; e-mail: kvv.doc@gmail.com. Sergeev Artyom Rubenovich – Department of Public Health’s, Assistant, I. M. Sechenov First Moscow State Medical University. Address: 8-2, Trubetskaya Str., Moscow, 119991, Russia; Phone: 8 (499) 2486024; e-mail: art.sergeev@mail.ru.

Refractive error is one of the biggest eye problems in young people. The most prevalent Refractive error, myopia, is continuously increased. The myopia degree impact results in serious eye complication. Current studies report that myopia is associated with genetic and hormonal mechanism. Second to Fourth-Digit Ratio (2D:4D) on the other hand, has been reported as having a relationship with genetic and hormonal mechanism. The study was aimed to observe association between Second to Fourth-Digit Ratio (2D:4D) and myopia cases in medical students of Medical Faculty of Jenderal Soedirman University. This was a quantitative observational analytic research with cross sectional approach. One hundred students, divided into myopia and emmetropia group, was recruited for the study. Digit measurement was done using a computer-based method by two independent observers, whereas eye refraction test was conducted by an independent Refractionist. Independent t-test on 2D:4D ratio showed no difference in values (p>0,05) between myopia and emmetropia group. As conclusion, study reported that there was no significant association between second to fourth-digit ratio (2D:4D) with myopia cases in medical students of Medical Faculty of Jenderal Soedirman University.

Purpose: To determine the diagnostic capability of spectral domain optical coherence tomography peripapillary retinal volume (RV) measurements. Materials and Methods: A total of 156 patients, 89 primary open-angle glaucoma and 67 normal subjects, were recruited. Spectral domain optical coherence tomography peripapillary RV was calculated for 4 quadrants using 3 annuli of varying scan circle diameters: outer circumpapillary annuli of circular grids 1, 2, and 3 (OCA1, OCA2, OCA3). Area under the receiver operating characteristic curves and pairwise comparisons of receiver operating characteristic (ROC) curves were performed to determine which quadrants were best for diagnosing primary open-angle glaucoma. The pairwise comparisons of the best ROC curves for RV and retinal nerve fiber layer (RNFL) were performed. The artifact rates were analyzed. Results: Pairwise comparisons showed that the smaller annuli OCA1 and OCA2 had better diagnostic performance than the largest annulus OCA3 (P

Purpose: To determine the diagnostic capability of spectral domain optical coherence tomography peripapillary retinal volume (RV) measurements. Materials and Methods: A total of 156 patients, 89 primary open-angle glaucoma and 67 normal subjects, were recruited. Spectral domain optical coherence tomography peripapillary RV was calculated for 4 quadrants using 3 annuli of varying scan circle diameters: outer circumpapillary annuli of circular grids 1, 2, and 3 (OCA1, OCA2, OCA3). Area under the receiver operating characteristic curves and pairwise comparisons of receiver operating characteristic (ROC) curves were performed to determine which quadrants were best for diagnosing primary open-angle glaucoma. The pairwise comparisons of the best ROC curves for RV and retinal nerve fiber layer (RNFL) were performed. The artifact rates were analyzed. Results: Pairwise comparisons showed that the smaller annuli OCA1 and OCA2 had better diagnostic performance than the largest annulus OCA3 (P

This paper discusses the relevance of the non-contact intraocular pressure (non-contact tonometer, NCT) and the diopter value measurements of refractive errors. Methods for the measurement of both eyes IOP of 192 patients, and binocular eye refraction as well, then the measured data were statistically analyzed. Research on age, gender, which eye, refractive power and refractive status (i.e. myopia, face, and hyperopia) affects the values of non-contact tonometer measurements. The results of refractive measurements were as follows: myopia, emmetropia and hyperopia accounted as 47.92, 15.62 and 36.46 % respectively. IOP measurement of all ages: age of 10 years old group (17.74 ± 3.34) mmHg, 10–20 years old group (17.85 ± 3.34) mmHg. According to gender, the male gender (17.94 ± 3.12) mmHg, and female (17.92 ± 3.23) mmHg. Group of the different eye, right eyes IOP was (18.05 ± 3.12) mmHg, left eyes IOP was (17.88 ± 3.17) mmHg. According to refractive errors: myopia group IOP was (17.83 ± 2.95) mmHg, hyperopia group IOP was (18.12 ± 2.94) mmHg, and emmetropia group IOP was (17.81 ± 3.16) mmHg. The results are: As we age, non-contact tonometry values tended to increase; gender has no effect on IOP measurement; detecting IOP found the value of the right eyes higher than the left eye; the refractive errors of (hyperopia, myopia and emmetropia); The values of IOP of myopia and hyperopia are higher than the emmetropia eyes.

Two stunning/slaughtering methods, ice asphyxia and carbon dioxide narcosis, as common capture procedures in commercial farms, were compared with asphyxia without ice in order to assess their suitability as stunning methods for European sea bass. In this study we have analyzed the stunning effects on the stress response related to fish welfare, and on the meat quality. Sampling was performed 0, 2, 9, 24, 48, 72 and 96 h after death, and for all sampling times, rigor mortis assessment, muscle pH, eye refraction index and sensory evaluation were determined as quality parameters. Moreover, osmolality, glucose, lactate and cortisol were determined as stress indicators. The muscle pH values were significantly lower in CO 2 narcosis group from the first 9 h until the end of the study in comparison to the respective zero time. If we compared muscle pH values between each slaughtering method with the asphyxia group through sampling time, we observed statistically higher values in CO 2 and ice asphyxia throughout the study. The sensorial evaluation showed a progressive decrease in the three groups analysed versus the respective zero time, although the comparison with the control group showed statistical differences only at zero and nine hours sampling time. Regarding stress indicators, all of them showed significant higher levels after both slaughtering methods compared with the undisturbed group and significant lower levels if compared with the asphyxia group. Our results also show that asphyxia produced a five-fold increase in glucose levels whereas other methods studied only produced a 1.5–1.7-fold increase. Cortisol levels increased 8-fold after asphyxia whereas the other slaughtering methods provoked a 5-fold increase. In summary, the results indicate that both methods are suitable to process fish although the CO 2 treatment showed lower lactate and cortisol response compared to asphyxia in ice. In terms of quality, differences between methods are minor.

Eye Refraction Anomalies in Down Syndrome Families The extra chromosomal material in Down syndrome patients causes a generalised disruption in the genetic balance. From this viewpoint, the non-specific developmental instability following aneuploidy might be also responsible for ocular anomalies in patients with Down syndrome. The aim of this study was to identify the eye refraction anomalies in families having individuals with Down syndrome. A total of 199 Down syndrome patients (average age 17.0 years), 85 their siblings (17.0 years) and 229 their parents (average age 48.9 years) underwent eye refraction examination. In Down syndrome patients ocular refractive findings as spherical equivalent were: emetropia 4.2±1.0%, hypermetropia 70.0±2.3%, and myopia 25.8±2.2%. Astigmatism was diagnosed in 42.8±1.5% of patients. Refraction could not be identified in 3.8±1.0% of patients. In the control group of siblings refractive findings as spherical equivalent were: emmetropia 51.2±3.8%, hypermetropia 39.4±3.7%, and myopia 9.4±2.2%. Astigmatism was diagnosed in 7.6±2.0% of siblings. In parents refractive findings as spherical equivalent were: emmetropia 42.8±2.3%, hypermetropia 40.2±2.3%, and myopia 17±1.8%. Astigmatism was diagnosed in 7.9±1.3% of parents. Refraction could not be identified in 1.1±0.5% of parents. Astigmatism, which is phylogenetically more recent, was found in Down syndrome patients 5.6 times more often than control siblings and 5.4 times more than in the parents group.

The aim of this work was to evaluate several anaesthetization methods such as clove oil, hypothermia and asphyxia in Senegal sole (Solea senegalensis), a highly resistant species to hypoxic conditions. The overall intent of the study was to determine a method that minimizes pre mortem stress and maximizes final product quality in sole for market sale. Several pre and post mortem indicators were considered for this study, namely rigor mortis, muscle pH, ATP/IMP ratios, eye refraction index and sensorial attributes. In addition, the stress experienced by the fish pre mortem was assessed by measuring cortisol, glucose and osmolality levels in blood plasma just after death (post mortem). Based on these physiological indicators, the results revealed that of the three methods considered, 1 ml·L �1 clove oil was the best method for stunning sole because it not only ensures a good final quality

Previous studies have shown an association of visual demands during near work and increased activity of the trapezius muscle. Those studies were conducted under stationary postural conditions with fixed gaze and artificial visual load. The present study investigated the relationship between ciliary muscle contraction force and trapezius muscle activity across individuals during performance of a natural dynamic motor task under free gaze conditions. Participants (N=11) tracked a moving visual target with a digital pen on a computer screen. Tracking performance, eye refraction and trapezius muscle activity were continuously measured. Ciliary muscle contraction force was computed from eye accommodative response. There was a significant Pearson correlation between ciliary muscle contraction force and trapezius muscle activity on the tracking side (0.78, p

A new approach to alterations in eye refraction upon nondestructive laser action on the sclera and cornea is studied. It is demonstrated in in vivo experiments on rabbit eyes that sequential laser irradiation of the sclera and cornea yields a significant alteration in the eye refraction. The collagen structure of the sclera and cornea is studied after the nondestructive laser action with noninvasive polarization-sensitive optical coherence tomography. It is demonstrated that collagen fibers that provide for the cornea tension and applanation partially survive in the zone of the local denaturation of sclera. An irradiation mode that corresponds to an increase in the cornea’s plasticity and does not cause visible structural changes is chosen. The simplest theoretical model for alterations in the eye refraction upon the nonablative laser action on sclera is analyzed. The alteration in the cornea curvature upon stretching resulting from the local sclera coagulation and the corresponding decrease in its volume is calculated. The model makes it possible to approximately estimate the laser irradiation modes that provide the desired alterations in eye refraction.

The aim of this study was to study the influence of growth hormone deficiency (GHD) on emmetropization and to evaluate the effect of growth hormone replacement therapy on eye refraction. Twenty-eight children affected by congenital GHD and undergoing substitutive therapy (group 1), and 28 healthy subjects (group 2), were prospectively studied. All patients had a thorough eye examination, including cycloplegic refraction and axial length measurement (only GHD children). After 2 years, we found in both groups a reduction of the dioptric power of the eye. A t test for paired data showed statistically significant differences in both groups (p < 0.001), but the change of refraction was higher in group 2 (p < 0.01). Axial length showed a statistically significant increase, according to the myopic shift (p < 0.001). The change of the refraction found in GHD children could be related to the somatic growth and partially induced by growth hormone therapy. The difference between the two groups could be explained with the late beginning of the therapy in GHD children. It is possible to form the hypothesis that a correct and well-timed substitutive therapy could permit a normal emmetropization process.

Purpose: To investigate the refractive outcomes after arcuate keratotomy for astigmatism. Setting: Uludag University, Faculty of Medicine, Department of Ophthalmology, Bursa, Turkey. Method. Sixteen eyes of 11 patients with astigmatism had arcuate keratotomy using the Terry astigmatome. The mean age of the patients was 36 years +/- 10 (SD). All patients received preoperative and postoperative ophthalmic examinations consisting of best spectacle-corrected (BSCVA) and uncorrected (UCVA) visual acuities, corneal topography, and ultrasonic pachymetry. Surgery was performed using topical anesthesia of oxybuprocaine 0.1% eyedrops. The Terry astigmatome was selected by the mean paracentral (estimated incision area) corneal thickness. All patients received topical ofloxacin 0.3% and topical diclofenac 0.1% eyedrops postoperatively. Results: The mean corneal astigmatism was -4.0 +/- 1.1 diopters (D) (range -2.2 to -6.0 D) preoperatively and -1.8 +/- 0.8 D (range -0.6 to -3.0 D) postoperatively. The mean surgically induced corneal astigmatism was 2.5 +/- 0.6 D. The mean UCVA (logMAR) was 0.74 +/- 0.25 preoperatively and 0.18 +/- 0.23 1 week postoperatively, and the mean BSCVA (logMAR) was 0.19 +/- 0.24 and 0.19 +/- 0.23, respectively. There were no intraoperative or postoperative complications. Conclusion: Arcuate keratotomy using the Terry astigmatome was a safe and reliable treatment for corneal astigmatism.

Aim. To conduct an analysis of the refraction of the vision organ of school children living and studying in an area with high intensity of automobile traffic, and in children living in a more environmentally clean area. Methods. The investigation of eye refraction in 62 children (124 eyes) of school age, living and studying in an area with high intensity of automobile traffic. Hygienic assessment of the environment in the study areas. Results. In the majority of the school children living and studying in an area with high intensity of automobile traffic a myopic refraction was revealed in contrast to the control area, where the frequency of myopia was less. The obtained data on the frequency of myopic refractive disorders in the children’s population were above the average statistics for the Russian Federation. A significant relationship between the nature and intensity of air pollution and the occurrence of myopia in children was established. We assume that one of the risk factors for myopia development is air pollution emissions by a complex of hazardous substances. Conclusion. Prophylaxis of eye diseases of children living in ecologically unfavorable areas of large cities is much needed; therapeutic measures for vision organ dysfunctions of this cohort should be implemented taking into account the influence of adverse environmental factors.

A new approach is proposed for correcting the eye refraction by controlled variation of the mechanical properties of the sclera and cornea upon nondestructive laser heating. Experimental ex vivo studies of rabbit and pig eyes show that laser-induced local denaturation of the sclera changes the refraction of the cornea by 3 diopters on the average, and the subsequent nondestructive irradiation of the cornea increases its plasticity, which leads to a further increase in its radius of curvature and a decrease in refraction down to 7 diopters.

We have studied the possibility of improving the performance, simplifying, and reducing the cost of a double-pass system by the use of alternative technologies. The system for correcting the spherical correction has been based on a focusable electro-optical lens, and a recording device based on CMOS technology and a superluminescent diode (SLED) light source have been evaluated separately. The suitability of the CMOS camera has been demonstrated, while the SLED could not break the speckle by itself. The final experimental setup, consisting of a CMOS camera and a laser diode, has been compared with a commercial double-pass system, proving its usefulness for ocular optical quality and scattering measurements. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)

A model is proposed for the fluctuations in eye refraction and a physical interpretation of the errors in measuring the clinical refraction in optometry that result from this. A theoretical limit is calculated for the measurement of normal eye refraction, which is about 0.15–0.3 m−1 (diopters).

Background The eye and the progressive lenses in eyeglasses form a three-dimensional optical system, which must be well matched. Patient A 71-year-old man complained about a new and unusual tearing and scratching sensation in his eyes. The work-up revealed subnormal values of the Schirmer test, from the eye refraction of different eyeglass powers and strongly decentred progressive lenses in his, just a few-months-old, eyeglasses. Therapy and outcome A lubricating therapy remained without success. However, the use of new and correct eyeglasses eliminated the symptoms. Conclusion Tearing and the sensation of scratching in the eyes in this case are symptoms of an eyeglasses-induced asthenopia. Consequently, it may pay to control the eyeglasses and the centration of progressive lenses in cases with unclear, unspecific eye symptoms even without dissatisfaction with eyeglasses.

Nowadays cataract surgery is refractive surgery as well. Intraocular lens implantation is gold standard, but there is plenty types of intraocular lenses, monofocal, multifocal, accommodating, and toric. Problem is to pick up correct one according life style, profession, health status and age. The aim is review current possibilities in cataract, refractive surgery and aphakia management.

To evaluate wavefront aberrations and subjective quality of life after toric intraocular lens (TIOL) implantation.Three groups of subjects who underwent unilateral cataract surgery with intraocular lens (IOL) implantation were compared: (1) toric group (n=40): corneal astigmatism1.50 D, implanted with Acrysof toric SN60TT IOL (Alcon Inc, Fort Worth, Texas, USA); (2) astigmatic SN60AT group (n=40): corneal astigmatism1.50 D, implanted with Acrysof SN60AT IOL; and (3) control group (n=40): corneal astigmatism1.00 D, implanted with Acrysof SN60AT IOL. Uncorrected distance visual acuity (UDVA), refraction, lower order astigmatism (Z(2)2, Z(-2)2), Strehl ratio and the modulation transfer function area ratio were evaluated over a 3 month follow-up period. A standardised quality of life test (National Eye Institute Refractive Error Quality of Life Instrument-42) was distributed to both astigmatic groups 3 months postoperatively.Postoperative UDVA and aberrometric values were significantly better (p0.001) and mean postoperative spherical equivalent was significantly lower (p0.05) in the toric and control groups compared with the astigmatic SN60AT group. The toric group had significantly better postoperative quality of life compared with the astigmatic SN60AT group (p0.05).Acrysof TIOL implantation resulted in better visual, refractive and aberrometric results than SN60AT spherical IOL implantation in astigmatic patients, similar to the control group. The better objective optical and retinal image quality resulted in better subjective quality of life after TIOL implantation.

The correction of the eye refraction under nondestructive laser action on the cornea and sclera is studied in-vitro at the constant intraocular pressure. The physical processes and mechanisms of laser induced modification of the refraction are considered. A theoretical model for alterations in the eye refraction upon the non-ablative laser action on sclera is presented and analyzed. The results allow determining the laser settings for desirable changes in refraction.

To compare the prevalence and risk factors for myopia in 6- and 7-year-old children of Chinese ethnicity in Sydney and Singapore.Two cross-sectional samples of age- and ethnicity-matched primary school children participated: 124 from the Sydney Myopia Study and 628 from the Singapore Cohort Study on the Risk Factors for Myopia. Cycloplegic autorefraction was used to determine myopia prevalence (spherical equivalentor = -0.5 diopter). Lifestyle activities were ascertained by questionnaire.The prevalence of myopia in 6- and 7-year-old children of Chinese ethnicity was significantly lower in Sydney (3.3%) than in Singapore (29.1%) (P.001). The prevalence of myopia in 1 or more parents was 68% in Sydney and 71% in Singapore. Children in Sydney read more books per week (P.001) and did more total near-work activity (P = .002). Children in Sydney spent more time on outdoor activities (13.75 vs 3.05 hours per week; P.001), which was the most significant factor associated with the differences in the prevalence of myopia between the 2 sites.The lower prevalence of myopia in Sydney was associated with increased hours of outdoor activities. We hypothesize that another factor contributing to the differences in the prevalence of myopia may be the early educational pressures found in Singapore but not in Sydney.

Purpose To evaluate the technique, efficacy, and safety of posterior iris fixation of iris-claw intraocular lens (IOLs) implantation through a scleral tunnel incision for aphakia correction. Design Noncomparative, interventional case series. Methods A secondary posterior iris fixation of the Artisan iris-claw IOL (Ophthec BV, Groningen, The Netherlands) was implanted for aphakia correction in the authors’ clinical practice. Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), astigmatism, manifest refraction, lens position, pigment dispersion, and intraocular pressure (IOP) were evaluated in 32 consecutive eyes of 32 patients. Results BSCVA was 20/40 or better in 28 eyes (87.50%) during the mean follow-up time (nine months). Mean postoperative spherical equivalent was −0.70 diopters (D; standard deviation [SD], 0.47 D) at six months after surgery. Mean prediction error was −0.13 D (SD, 0.28 D), and mean absolute prediction error was 0.26 D (SD, 0.15 D). Preoperative mean astigmatism was −1.08 D (SD, 0.55 D; range, 0.0 to −2.0 D). At six months after surgery, mean astigmatism was −2.1 D (SD, 0.81 D; range, −0.75 to −3.75 D). There was no significant postoperative IOP increase. Lens position, evaluated by Oculus Pentacam (Pentacam 70700: Oculus, Wetzlar, Germany) and ultrasound biomicroscopy [UBM] (Ophthalmic Technologies Inc, Toronto, Ontario, Canada), was parallel to the iris plane. Conclusions Posterior iris fixation of the iris-claw IOL implantation through a scleral tunnel incision is a safe procedure and an effective option for aphakic eyes without capsule support.

The child health-care guideline 'Detection of visual disorders at the age of 0-19' draws attention to the importance of early detection of visual disorders and provides guidelines to child health-care workers for detecting disorders during routine check-ups. Children under the age of 3 are examined by the 'Early detection of visual disorders' method. Picture charts may be used for children from the age 3 onwards. From the age of 3-5 charts which follow the Snellen principle such as the Landolt-C chart should be used. Screening for refraction after the age of 7 and screening for colour blindness are not necessary. Children born before 32 weeks of pregnancy, children with a family history of visual disorders and mentally disabled children have an increased risk of visual disorders.

The child health-care guideline 'Detection of visual disorders at the age of 0-19' draws attention to the importance of early detection of visual disorders and provides guidelines to child health-care workers for detecting disorders during routine check-ups. Children under the age of 3 are examined by the 'Early detection of visual disorders' method. Picture charts may be used for children from the age 3 onwards. From the age of 3-5 charts which follow the Snellen principle such as the Landolt-C chart should be used. Screening for refraction after the age of 7 and screening for colour blindness are not necessary. Children born before 32 weeks of pregnancy, children with a family history of visual disorders and mentally disabled children have an increased risk of visual disorders.

Technological advance has transformed some of the simple optical systems devised more than 100 years ago into the highly sophisticated refracting instruments available today. Probably these modem automated optometers will be shown to represent only the first stage in the field of automated eye refraction and even in the decade or so with which they have been with us we can see the improvements which have been made in their performance. They obtain levels of accuracy similar to retinoscopy and can serve adequately as a preliminary refracting aid although they do still have some inadequacies in dealing with the ‘problem patient. None yet has the accuracy from which to prescribe directly, and neither does my claim to be a replacement for the practitioner. Possibilities exist for them to be lncorporated into a preliminary data-gathering procedure, providing the patient with a more extensive examination and also saving the examiner time so that the size of the practice can be expanded. In screening populations such as school children or work forces they seem to have great potential.

In this work the presence of gamma-glutamyltransferase (GGT), leucine amino-peptidase (LAP) and alkaline phosphatase (AP) is shown in human tear fluid. We studied these levels according to sex, age and some eye refraction defects. The differences between the levels for both sexes are not significant. LAP and AP do not show any differences in either age groups or individuals with some refraction defects. The average level of GGT is higher from 40 years of age upwards (p less than 0.005). In individuals with refraction defects, the enzymatic activity is significantly higher (p less than 0.05) than the activities found in normal subjects. The levels of the three enzymes in serum and tear fluid do not show a significant correlation nor are they significantly modified after the samples have been frozen for a month at -20 degrees C.

Several years ago I happened to take part in surveying a large group of schoolchildren. Many of them were unhealthy. Their disorders ranged from eye refraction to gastrointestinal, cardiovascular, and nervous diseases-and that was starting from the fifth grade. At one of the Komsomol Central Committee conferences in October 1986 it was noted that a detailed survey of schoolchildren, in particular in the Far East, showed that the percentage of healthy children had declined drastically. During the 1970s and 1980s I questioned educators and schoolchildren in the United States, England, the FRG, Japan, and France. The problem of children's health in those countries is not acute. The well-known pediatrician Benjamin Spock, about whom I have written a great deal, said: "We do have children's injuries, but as for other disorders, they are minimal."

The measurements of eye refraction, obtained with the aid of two conventional techniques, such as vision test charts and Badal’s optometer, are known to agree with the data obtained with the recent laser refractors, the accuracy being of one quarter of a diopter. The present paper aims at comparing the principles on which the above said three techniques are based. The main difference seems to lie in the fact that the apparent movement of the laser speckles, denoting a situation of defocus, does not stimulate the accommodation reflex as the sensation of blur does.

Refraction of the laterally implanted eyes of the rabbit was measured in various directions. It was found that the eye is slightly hypermetropic laterally and strongly myopic frontally. The hypothesis was developed that frontal vision is of importance for the detection of objects at small distances, for instance food, and lateral vision for the detection of remote objects, for instance natural enemies.

Lasers have already found several diagnostic applications in ophthalmology. For example, the techniques of laser Doppler anemometry [1] have been used to measure retinal blood flow [2,3] and optic nerve-head compliance [4] , and the possibility of measuring eye dilatation by means of laser interferometry is presently under investigation [5, 6]. The properties of laser speckle [7] have also been exploited, in the measurement of eye refraction [8, 9].