Effects of color-enhancing glasses on color vision in congenital red-green color deficiencies.

As commercially available glasses for color vision deficiency (CVD) are classified as low risk, they are not subject to stringent marketing regulations. We investigate how EnChroma and VINO glasses affect performance on the Colour Assessment and Diagnosis (CAD) test in individuals with CVD. Data were obtained from 51 individuals with red-green CVD. Blood or saliva samples were collected to examine the structure of the OPN1LW/OPN1MW array. Individuals completed the CAD test twice without glasses and once with each pair of glasses. Although there was a statistically significant effect of both glasses, only that of VINO could be considered functionally meaningful.

Mechanisms of Light-Induced Deformations in Photoreceptors.

Biological cells deform on a nanometer scale when their transmembrane voltage changes, an effect that has been visualized during the action potential using quantitative phase imaging. Similar changes in the optical path length have been observed in photoreceptor outer segments after a flash stimulus via phase-resolved optical coherence tomography. These optoretinograms reveal a fast, millisecond-scale contraction of the outer segments by tens of nanometers, followed by a slow (hundreds of milliseconds) elongation reaching hundreds of nanometers. Ultrafast measurements of the contractile response using line-field phase-resolved optical coherence tomography show a logarithmic increase in amplitude and a decreasing time to peak with increasing stimulus intensity. We present a model that relates the early receptor potential to these deformations based on the voltage-dependent membrane tension-the mechanism observed earlier in neurons and other electrogenic cells. The early receptor potential is caused by conformational changes in opsins after photoisomerization, resulting in the fractional shift of the charge across the disk membrane. Lateral repulsion of the ions on both sides of the membrane affects its surface tension and leads to its lateral expansion. Because the volume of the disks does not change on a millisecond timescale, their lateral expansion leads to an axial contraction of the outer segment. With increasing stimulus intensity and the resulting tension, the area expansion coefficient of the disk membrane also increases as thermally induced fluctuations are pulled flat, resisting further expansion. This leads to the logarithmic saturation observed in measurements as well as the peak shift in time. This imaging technique therefore relates the structural changes in the photoreceptor to the underlying neurological function of transducing light into electrical signals. Such label-free optical monitoring of neural activity using fast interferometry may be applicable not only to optoretinography but also to neuroscience in general.

[Historical Development of the Wool and Colour Plate Tests for Screening for Colour Vision Deficiencies in German Speaking Countries]. / Historische Entwicklung von Wollproben- und Farbtafeltests für das Screening von Farbsehstörungen im deutschsprachigen Raum.

Colour vision is a complex visual function that can be affected by congenital and/or acquired disorders. The frequency of congenital colour vision deficiencies has been investigated in rail and navy staff since the 1870s. Various test methods have been developed. Wool tests, flor contrast tests and colour plate tests have been used. A published colour plate test, based on Stilling's pseudo-isochromatic plates in combination with a flor contrast test, has been a common screening method for colour vision testing in German-speaking countries. This test is intended to detect congenital and acquired colour vision deficiencies in a simple and safe manner. More modern options, such as Internet and tablet PC have technical limitations, but will increasingly be used for screening for colour vision deficiencies.

[Investigation of Color Vision Using Pigment Color Plates and a Tablet PC]. / Untersuchung des Farbsehens mittels Pigmentfarbtafeln und Tablet-PC.

BACKGROUND: Many applications (apps) for ophthalmic solutions, including colour vision tests, are currently available. However, no colour vision test app has been evaluated through clinical trials on a tablet PC. METHOD: Using standard test conditions and a tablet pc (iPad2®), colour vision tests were performed with 19 Velhagen/Broschmann/Kuchenbecker colour plates and an HMC anomaloscope. The plates were alternately presented at first in a book (pigment colour plates) and then in a tablet PC (iPad®). A total of 77 volunteer subjects were examined. 62 subjects were colour normal and 15 male subjects had a colour vision deficiency. The coincidence and the 95 % confidence intervals were determined. RESULTS: The average age of all subjects (n = 77) was 42.8 ± 16.9 years. The mean near visual acuity of all subjects was 0.99 ± 0.15. The coincidence of the results of all subjects between books and tablet PC was 88.0 %. The 95 % confidence interval ranged from 81.6 to 89.6 %. In the group of subjects with colour vision deficiency (n = 15), the coincidence was 83.3 %. The 95 % confidence interval ranged from 78.4 to 87.3 %. In the group of subjects without colour vision deficiency (n = 62), the coincidence was 89.1 %. The 95 % confidence interval ranged from 87.1 to 90.8 %. The overlap of error numbers of colour normal subjects and colour vision deficiency subjects was 2 errors with the book and 5 errors with the tablet pc. CONCLUSIONS: Testing colour vision using book and tablet pc only gives roughly comparable results. However, separation with the book was better and the colour plates differed in validity. For this reason, only some of the colour plates could be used on a tablet PC.

[Investigation of color vision in acute unilateral optic neuritis using a web-based color vision test]. / Untersuchung des Farbsehens bei akuter einseitiger Neuritis nervi optici mittels eines webbasierten Farbsehtests.

BACKGROUND: In acute unilateral optic neuritis (ON) color vision defects combined with a decrease in visual acuity and contrast sensitivity frequently occur. This study investigated whether a web-based color vision test is a reliable detector of acquired color vision defects in ON and, if so, which charts are particularly suitable. METHODS: In 12 patients with acute unilateral ON, a web-based color vision test ( www.farbsehtest.de ) with 25 color plates (16 Velhagen/Broschmann and 9 Ishihara color plates) was performed. For each patient the affected eye was tested first and then the unaffected eye. RESULTS: The mean best-corrected distance visual acuity (BCDVA) in the ON eye was 0.36 ± 0.20 and 1.0 ± 0.1 in the contralateral eye. The number of incorrectly read plates correlated with the visual acuity. For the ON eye a total of 134 plates were correctly identified and 166 plates were incorrectly identified, while for the disease-free fellow eye, 276 plates were correctly identified and 24 plates were incorrectly identified. Both of the blue/yellow plates were identified correctly 14 times and incorrectly 10 times using the ON eye and exclusively correctly (24 times) using the fellow eye. The Velhagen/Broschmann plates were incorrectly identified significantly more frequently in comparison with the Ishihara plates. In 4 out of 16 Velhagen/Broschmann plates and 5 out of 9 Ishihara plates, no statistically significant differences between the ON eye and the fellow eye could be detected. CONCLUSION: The number of incorrectly identified plates correlated with a decrease in visual acuity. Red/green and blue/yellow plates were incorrectly identified significantly more frequently with the ON eye, while the Velhagen/Broschmann color plates were incorrectly identified significantly more frequently than the Ishihara color plates. Thus, under defined test conditions the web-based color vision test can also be used to detect acquired color vision defects, such as those caused by ON. Optimization of the test by altering the combination of plates may be a useful next step.

Exclusive breastfeeding and its effect on growth of Malawian infants: results from a cross-sectional study.

BACKGROUND: For the optimal nutrition of children under 2 years of age, it is considered important that they be exclusively breastfed for the first 6 months before being given complementary food. AIMS AND OBJECTIVES: A cross-sectional nutritional baseline survey was undertaken in 2011 in the Kasungu and Mzimba Districts of Malawi to assess the nutritional status of children under 2 years of age and its determinants in order to prepare a nutrition education intervention programme. The intention of this study was to assess the nutritional status of infants aged 0-<6 months with regard to food intake. METHODS: Interviews were conducted on randomly selected families with children under 2 years; anthropometric measurements were obtained from mothers and their children. Only infants between 0 and <6 months were selected for analysis (n  =  196). An ANCOVA test was performed on age of the infant with mothers' height and weight as covariates. RESULTS: Prevalence of stunting (infants' length-for-age Z-score (LAZ) <-2SD) was 39%, wasting (WLZ <-2SD) 2%, and underweight (WAZ <-2SD) 13%. Of the infants under 6 months, 43% were exclusively breastfed. Predominant breastfeeding and mixed breastfeeding were less common (21% and 36%, respectively). The ANCOVA confirmed the association between exclusive breastfeeding and LAZ and WAZ: exclusively breastfed infants had a higher mean (SE) LAZ (-1.13, 0.12) and WAZ (-0.41, 0.13) than infants not being exclusively breastfed (-1.59, 0.11, and -0.97, 0.11, respectively). There was no overall significant association between breastfeeding practice and WLZ. CONCLUSION: Exclusive breastfeeding of infants under 6 months is associated with higher mean LAZ and WAZ. Promotion of exclusive breastfeeding in low-income countries is important in preventing growth retardation.

[Web-based analysis of Stilling's color plates]. / Webbasierte Analyse von Stilling-Farbtafeln.

BACKGROUND: Color vision tests with pseudoisochromatic plates currently represent the most common procedure for the screening of congenital color vision deficiencies. By means of a web-based color vision test, new and old color plates can be tested for diagnostic quality without major effort. METHODS: A total of 16 digitized Stilling's color plates of the 11th edition from 1907 were included in a web-based color vision test (http://www.farbsehtest.de). The χ(2)-test was used to check whether the Stilling color plates showed similar results to the nine previously evaluated Ishihara color plates. RESULTS: A total of 518 subjects including101 (19.5 %) female subjects with a mean age of 34.6 ± 17 years, took the web-based test with the 25 plates. For all participants the range for the correctly recognized plates was between 5.2 % (n = 27) and 97.7 % (n = 506) for the Stilling color plates and between 64.9 % (n = 336) and 100 % (n = 518) for the Ishihara color plates. For participants with more than 5 errors (n = 247), the range for correctly recognized plates was between 2.0 % (n = 5) and 98.0 % (n = 242) for the Stilling plates and between 42.5 % (n = 105) and 100 % (n = 247) for the Ishihara plates. Taking all color plates and all participants into account there was a significantly higher incidence of erroneous recognition of the Stilling color plates (3038 false and 5250 true answers) compared to the Ishihara color plates (1511 false and 3151 true answers) (p < 0.001, χ(2)-test). CONCLUSION: The diagnostic quality of the tested Stilling color pates was very variable. Some of the plates could be used for the test edition of the Velhagen/Broschmann/Kuchenbecker color plates from 2014. Overall, the Stilling color plates were recognized with a higher incidence of error by all participants in the web-based test compared to the utilized Ishihara color plates, which in most cases was attributable to ambiguity of some symbols.

[Therapy of neovascular glaucoma. The outcome of IOP using concomitant therapy consisting of retinal kryocoagulation, diode laser coagulation, and intravitreal injection of bevacizumab]. / Therapie des rubeotischen Sekundärglaukoms IOD-Verlauf nach Kombinationstherapie bestehend aus Zyklophotokoagulation (CPC), Kryokoagulation und intravitrealer Bevacizumab-Injektion.

BACKGROUND: Intravitreal Bevacizumab has been used as adjunct treatment to diode laser cyclophotocoagulation and/or retinal photo-/cryocoagulation in eyes with neovascular glaucoma and is discussed to reduce intraocular pressure and rubeosis irides in addition. METHODS: This study investigated the drop of the intraocular pressure of 23 patients who were treated by a concomitant therapy consisting of retinal kryocoagulation, diode laser coagulation and intravitreal injection of Avastin(®) administered in one session. RESULTS: At the time of discharge patients exhibited a 55.1 % (19.7 mmHg) decrease in intraocular pressure and also a 48.7 % (17.4 mmHg) decrease in regard to follow-up results. Topical agents were not significantly decreased with 2.1 agents at the beginning of treatment and 1.9 at the time of discharge. Furthermore, the systemic administration of acetazolamide was reduced from 12 patients at the beginning to 2 patients at the time of discharge. In 21 cases the intraocular pressure returned to normal levels, whereas the other two patients were pain-free after treatment. CONCLUSION: With the administration of triple therapy, the intraocular pressure showed a significant reduction. There were no severe complications and the symptoms also were improved significantly.

[Test-retest reliability of a web-based colour vision test]. / Untersuchungen zur Re-Test Reliabilität eines webbasierten Farbsehtests.

BACKGROUND: Screening tests should be simple, with high acceptance, low costs and offer a high sensitivity and specificity as well as high reliability. The test-retest reliability of a web-based colour vision test was evaluated. METHOD: The results of 386 subjects, who had performed the web-based colour vision test with 25 colour plates twice (available at http://www.farbsehtest.de), were analysed from an mySQL data base. Retests were performed spontaneously, normally on the same day, or through an email newsletter with a request to repeat the test. Test-retest reliability was assessed by calculating the kappa coefficient and the corresponding confidence interval. The McNemar test was used as a complementary procedure to detect the presence of systematic differences between test results. RESULTS: The kappa coefficient rises with increasing time interval between the first test performance and the test repetition. Thus it was 0.24 when the test was repeated within one hour (confidence interval 0.07 - 0.41, n = 63), it increases to 0.83 (confidence interval 0.75 - 0.92, n = 240) in the subjects who repeated the test at the earliest after two years. While the proportion of failed tests (< 3 mistakes) in the second test performance markedly decreases when the test is repeated in the short term within one hour (p < 0.001, McNemar), we were unable to identify any systematic differences (p = 0.602) for a time interval of more than one day. CONCLUSIONS: The web-based colour vision test is a reliable screening test with good reproducible results as well under uncontrolled examination conditions. Subjects must perform the test with serious intent and should not aim at a positive test result by training or manipulation because of self-delusion. Test results are reliable if the time interval between test and retest is more than one day.

[Solitary extramedullary plasmocytoma of the conjunctiva]. / Isoliertes extraossäres Plasmozytom der Konjunktiva.

There is a wide variety of conjunctival tumors. A good diagnosis can be reached by discussing the case history with the patient in conjunction with a slit-lamp examination. Presented here is the case of a 39-year-old patient with a rapidly growing conjunctival tumor on his left eye. After tumor resection and histological analysis, a plasmacytoma was found. The completed hemato-oncological analysis gave no further suspicious pathological results, leading to the diagnosis of a solitary extramedullary plasmacytoma. Percutaneous radiotherapy was carried out.

[Validity of a web-based color vision test for screening examinations of color vision]. / Untersuchungen zur Validität eines webbasierten Farbsehtests für Screeninguntersuchungen des Farbensehens.

BACKGROUND: With standardized examination conditions, a web-based color vision test using pseudoisochromatic color plates can deliver test results comparable to those yielded by conventional color vision tests. The aim of the study is to analyze to what extent a web-based color vision test can be used as a screening test on the internet after visual monitor calibration. METHODS: A German-language web-based color vision test with 25 pseudoisochromatic color plates based on the color plates of Velhagen and Broschmann and of Ishihara was developed, which can be seen at http://www.farbsehtest.de. Volunteers were recruited by means of specific information distributed on the internet, in various print media, and on the radio. RESULTS: Over a period of 12 months, 2,126 of the initial volunteers [541 women and 1,588 men; mean age 34.27 (+/-14.1) years] with a valid test result for 25 color plates performed the web-based color vision test, 1,700 (506 women and 1,194 men) of whom passed it. Of the 426 volunteers who did not pass the test, 32 were women and 394, men. Counter-testing was performed on 101 volunteers (34 women and 67 men) with a mean age of 36.74 (+/-11.6) years. CONCLUSIONS: The results recorded in the patients who underwent counter-testing suggest that, if handled correctly, the web-based color vision test can be used as a color vision screening test on the internet.

[Influence of intraoperative pupil diameter and nuclear grade due to complications during Aqualase phacoemulsification]. / Einfluss von intraoperativer Pupillenweite und Kernhärte auf Komplikationen während der Aqualase-Phakoemulsifikation - eine Pilotstudie.

PURPOSE: The aim of this study was to make an evaluation of the frequency of intraoperative complications during Aqualase phacoemulsification and correlate it to different intraoperative pupil diameters and nuclear grades. METHODS: Aqualase phacoemulsification was performed in 23 eyes without retinal or optic disc pathology in 23 unselected patients (15 women and 8 men) who underwent out-patient cataract surgery. Nuclear grade, intraoperative pupil diameters and complications were recorded. The correlation of intraoperative complications with intraoperative pupil diameter and nuclear grade was determined using "Fisher's exact" test. RESULTS: The average age of our patients was 70.3 (+/- 12.5) years, the mean best spectacle-corrected visual acuity (BSCVA) preoperatively was 0.39 (+/- 0.15) and the mean BSCVA postoperatively was 0.79 (+/- 0.13). The mean aqua time was 3.11 s (+/- 1.55 s) with maximum nuclear sclerosis of up to grade 3 (mean nuclear sclerosis 1.9). The aqua time correlated with the nuclear sclerosis (r = 0.90). The mean intraoperative pupil diameter was 7.2 (+/- 0.7) mm. In 2 of 3 patients with an intraoperative pupil diameter of 6 mm, iris touch occurred intraoperatively. There were no other intra- or postoperative complications. The frequency of iris touch was statistically significantly higher for reduced pupil diameters (p = 0.01). The nuclear grade with a maximum of 3 was without statistical significance to iris touch frequency (p > 0.05). CONCLUSIONS: The number of iris traumas is significantly higher when the intraoperative pupil diameter is reduced. The iris should be protected in these cases. A prospective, randomised study should be performed to compare the number of intraoperative complications between ultrasound and Aqualase phacoemulsification.

[Use of an electronic patient record system at the Department of Ophthalmology, Otto-von-Guericke University of Magdeburg]. / Einsatz einer elektronischen Patientenakte (EPA) an der Universitätsaugenklinik Magdeburg.

BACKGROUND: The electronic or paper-based patient record is the most important documentation file. The electronic patient record has many advantages compared to a paper-based record. METHODS: An example of an electronic patient record (EPR) system accessed by several departments of the Faculty of Medicine of Magdeburg is presented. RESULTS: To guarantee faculty-wide communication with sharing of clinical pictures and findings, e.g., with the Departments of Radiology and Pathology, the system of MEDOS Inc. is used in our department. Several examination devices, for example fundus camera, slit lamp, and ultrasound, are equipped with an digital picture storage and communication system via a DICOM interface to the MEDOS system. The software AnalySIS is used as a gateway for picture transferation. The MEDOS system also supports the clinical workflow. CONCLUSIONS: The use of an electronic patient record system in ophthalmology is already possible, but still needs further tuning and improvement.

[Investigation of color vision using a web-based color vision test]. / Untersuchungen des Farbsinns mittels eines web-basierten Farbsehtests.

BACKGROUND: Screening tests of visual functions using the Internet are theoretically possible. To use these tests as a screening test, they must deliver comparable results with conventional test procedures. A web-based color vision test was developed based on pseudoisochromatic color plates. METHOD: The web-based color vision test was developed according to the pseudoisochromatic color plates by Velhagen and Broschmann using the programming-languages HTML, Java, and Perl. Sixty-five voluntary subjects, including nine color-deficient subjects, were examined by luminescence color plates (via web-based color vision test) and pigment color plates (via book). The statistical analysis was performed by determining the correspondence and the 95%-confidence interval. RESULTS: The correspondence of the test results for all subjects was 0.98 and the 95%-confidence interval was within 0.91 and 0.99. The correspondence of the test results in the group of color-deficient subjects was 1.0 and because of the limited number the 95%-confidence interval was within 0.71 and 1.0. CONCLUSIONS: The web-based color vision test with luminescence color plates for color-efficient and color-deficient subjects delivers test results comparable to pigment color plates under standardized examination conditions. Further studies are needed to examine if the web-based color vision test can also be used as an Internet screening test.

Visual function tests on the Internet--sense or nonsense?

BACKGROUND: The quantitative capability of the visual system can be tested using graphic presentations with defined size, form and color. For presentations, a chart projector or monitor can be used. Today, the number of visual function tests on the Internet is increasing constantly. Options and limitations of visual function tests using the METHODS: Internet and the authors' own test results are described. RESULTS: Several visual function tests, such as visual acuity tests, the Amsler-Grid, stereo and color vision tests, can already be given via Internet. The variability of the tests ranges from the simple presentation of graphic elements to the laboriously programmed interactive input by the user to specify the test result. Under standardized examination conditions, there was a very high correspondence between the results of the authors' own web-based color vision test and those of luminescence color test plates and conventional pigment color plates. CONCLUSIONS: However, the interpretation of the test results is difficult due to the absence of controls during the test as well as the heterogeneity of the hardware. In order to obtain comparable test results, differences in size and resolution as well as in brightness, contrast and color of computer monitors must be taken into consideration. Due to the deficits described in the tests, the value of visual function tests on the Internet is rather limited. Currently, the data of test distributers with respect to the test conditions are all still insufficient. Standards need to be defined for Internet-based visual function tests. However, visual function tests on the Internet can achieve test results comparable to those of conventional visual function tests under standardized examination conditions in clinical practice. Further studies are needed to check the accuracy of web-based screening examinations in ophthalmology.

[Options and limits of visual function tests available on the internet]. / Möglichkeiten und Grenzen der Testung visueller Funktionen mittels Internet Eine Analyse von Sehtests im Internet.

BACKGROUND: The quantitative capability of the visual system can be tested using graphic presentations with defined size, form and colour. For presentations a chart projector or personal computer (PC) can be used. In the meantime the number of visual function tests on the internet is continually increasing. These tests are potentially available for over 400 million internet users with different hard- and software requirements. METHODS: From 38 on-line visual acuity tests and 19 on-line colour vision tests found by means of search engines on german language web pages, the offerer of the test, the type of chart used and the data for the test conditions, as well as hard- and software adjustment were registered. RESULTS. Various visual function tests, such as visual acuity tests, the Amsler grid, stereo and colour vision tests, can already be planned via internet. The variability of the tests ranges from a simple presentation of graphic elements to a laboriously programmed interactive input by the user to specify the test result. Most of the tests are presented by opticians and the optical industry. DISCUSSION: The analysed tests allow for a considerable variability of the test conditions, for example by missing data concerning the room lighting and lacking monitor calibration. Furthermore, problems of the web-based colour presentation were not considered or not considered sufficiently in most of the on-line colour tests. CONCLUSIONS: Because of the test deficits determined, the results of visual function tests on the internet are to be classified as doubtful. At present, most data of test offerers are not sufficient with respect to the test conditions. Standards should be defined for internet-based visual function tests and further studies should be followed to check the effectiveness of these tests for screening examinations.

[Quantitative and objective topometrical analysis of drusen of the optic nerve head with the Heidelberg retina tomograph (HRT)]. / Quantitative und objektive topo-metrische Analyse von Drusenpapillen mit dem Heidelberg-Retina-Tomographen (HRT).

BACKGROUND AND PURPOSE: Optic nerve head drusen (ONHD) are one of the most frequent causes for congenital swelling of the optic nerve head. Visual field and retinal nerve fiber layer defects are reported in cases of ONHD. The Heidelberg Retina Tomograph (HRT) allows a 3-dimensional topometric analysis of the optic nerve disc and measurement of the peripapillary mean retinal nerve fiber layer. PATIENTS AND METHODS: A total of 18 eyes from 9 patients with sonographically confirmed drusen were analyzed with the HRT. Data were compared to a control group of 18 eyes from 9 matched healthy individuals. Statistical analyses were performed by using ANOVA (univariate). All patients with ONHD underwent a computerised visual field test (30 degrees, Octopus 101). Due to a bad reliability factor of over 10 in the visual fields by 4 out of 18 eyes, only measurements from 14 eyes were included in the study. We correlated visual field and HRT parameters and calculated the Pearson's correlation coefficient (r). RESULTS: We found a significant difference in the measured parameter mean retinal nerve fiber layer (RNFL) thickness ( p<0.05) between the two groups. In the ONHD group a negative correlation coefficient was found between the peripapillary mean RNFL thickness and the loss variance (r=-0.50, p=0.03) as well as between the peripapillary RNFL cross-sectional area and the loss variance (r=-0.47, p=0.04). CONCLUSIONS: The HRT is able to detect a peripapillary RNFL thinning in cases with ONHD. The mean RNFL thickness correlated with the loss variance. The HRT should be used to perform a quantitative and objective topometric analysis in cases with ONHD.