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J Kuchenbecker

Publications and source records attributed to J Kuchenbecker.

At least 19 recordsLinked to original sources
PubMed2007

[Validity of a web-based color vision test for screening examinations of color vision].

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.

Adolescent↗
PubMed2006

[Influence of intraoperative pupil diameter and nuclear grade due to complications during Aqualase phacoemulsification].

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.

Aged↗
PubMed2004

[Investigation of color vision using a web-based color vision test].

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.

Adult↗
PubMed2004

[Use of an electronic patient record system at the Department of Ophthalmology, Otto-von-Guericke University of 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.

Computer Communication Networks↗
PubMed2004

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.

Color Perception Tests↗
PubMed2002

[Quantitative and objective topometrical analysis of drusen of the optic nerve head with the Heidelberg retina tomograph (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.

Adult↗
PubMed2002

[Options and limits of visual function tests available on the 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.

Color Perception Tests↗
PubMed2001

[Internet-based teaching and learning in ophthalmology].

The transmission of clinical knowledge occurs traditionally through lectures, theoretical and practical courses, bed-side teaching as well as case-oriented teaching in small groups. The realisation is, however often very laborious and problematical because of low resources. For these reasons the development of computer-based, and in particular internet-based tutorials have increased dramatically in recent years. Furthermore, the transmission of knowledge by means of internet-based tutorials offers several advantages. The content can be quickly updated and multimedia presentations are possible. The use of these sources is normally independent of time and location. The possibilities of internet-based teaching and learning are on-line lectures, case simulations and online quizes. At present, the number of ophthalmological applications on the internet is still restricted. Internet-based multimedial tutorials represent a meaningful supplement to traditional forms of teaching. Especially in ophthalmology, a visual presentation of details can be performed in an easier way via multimedial tools and the training is followed without causing stress for the patients.

Computer Graphics↗
PubMed2001

[Electrophysiological studies in breast carcinoma patients with tamoxifen retinopathy].

PURPOSE: Crystalline plaques in the cornea or the retinal nerve fiber layer are well-known side effects of tamoxifen therapy. We investigated whether electrophysiological methods for determining the function of the retinal nerve fiber layer and retinal pigment epithelium demonstrate changes in tamoxifen retinopathy. PATIENTS AND METHODS: We compared the right eyes of four women with breast cancer and mono- or bilateral tamoxifen retinopathy to ten right eyes of age-matched, eyehealthy patients who had not received tamoxifen by means of electrophysiological investigations (e.g., pattern-reversal electroretinography, flash electroretinography for the maximal combined response, electrooculography; ISCEV standard conditions). RESULTS: No significant differences were observed between patients with tamoxifen retinopathy and controls regarding mean visual acuity, basal level of the electro-oculographic standing potential, basal level on the Arden index, or any of the other electrophysiological potentials. CONCLUSIONS: Pattern-reversal electroretinographic measurements revealed no damage of retinal ganglion cells in the presence of crystalline plaques in the retinal nerve fiber layer. Electro-oculography did reveal differences, but these were not statistically significant, possibly due to the small number of cases.

Aged↗
PubMed2001

Ophthalmodynamometry: a reliable method for measuring intracranial pressure.

Under physiological conditions, the pressure in the central retinal vein is equal to or higher than the intracranial pressure (ICP) because the cerebrospinal fluid (CSF) passes the sheath of the optic nerve before draining into the cavernous sinus. The optic nerve sheath is where the ICP affects the retinal venous pressure. Ophthalmodynamometry (ODM) is a useful method for determining the central retinal artery pressure. While papilledema and a lack of venous pulsations are commonly used as a vague indication of the ICP, ODM may be advantageous for determining the pressure in the central retinal vein. Until now, however, the venous pressure has never been compared with the intracranial pressure. In the present study, the pressure in the central retinal vein was recorded in 31 patients while the ICP was simultaneously being recorded for various reasons. The results demonstrate a linear correlation (r = 0.968) between the pressure in the central retinal vein and the ICP. This correlation is of great practical value since until now, reliable intracranial pressure monitoring has only been possible by invasive means, by placing a probe either in the brain parenchyma or the ventricle. Ophthalmodynamometry is useful for momentary assessment of the ICP, can easily be repeated, and may be used whenever an elevated ICP is suspected in hydrocephalus, brain tumors and after head injury. However, it is not suitable for continuous ICP monitoring.

Adolescent↗
PubMed2001

Use of internet technologies for data acquisition in large clinical trials.

Data acquisition for automated processing is a central aspect of clinical trials with large numbers of cases because of their extensive demand for manpower. Scientific data can be collected using data forms, which are created in Hypertext Markup Language and published on the Internet. The completed data form can be returned via E-mail or Common Gateway Interface-Script and forwarded into a study database. For the Internet-based data acquisition of a prospective multicenter trial (e.g., on endophthalmitis incidence after cataract extraction), we developed two special HTML forms that can be opened in the ophthalmology department's homepage. A large number of acquired anonymous data has been collected via Internet and automatically transferred into the trial database. The Internet provides a fast and easy avenue for the acquisition of scientific data. This method of data acquisition and data processing will become more common place in multicenter clinical trials.

Clinical Trials as Topic↗
PubMed2000

[On line ophthalmologic education. Live transfers and on demand lectures via Internet].

Continuing medical education for ophthalmologist is important and demanded from the board of ophthalmic organizations. The use of new multimedia possibilities provided by the internet, offers an alternative to acquire the training sessions requested by the board. Aim of the paper is to show the efforts made, to place an internet-based training website for ophthalmologists by transferring live ophthalmology events via the internet. The live-transfers of selected lectures is realized by transferring the original sound compatible to the software "Real-Audio-Player" with an rate of 8000 Hz (encoding-depth 14 bits). By using this software it is possible to follow the lectures live. It includes also 2 live-pictures of 2 digital camcorders to show the appropriate slides from the lecturer. The live broadcasted lectures were afterwards revised and are available at any time as "on-demand lectures" with original sound and slides. Since November 1997, 15 continuing medical education events for ophthalmologists of the University Erlangen-Nürnberg, Germany and from other universities were live broadcasted covering all aspects of phthalmology can be viewed as "on-demand lectures" with original-sound and slides under the internet-addresse http:¿www.onjoph.com/deutsch/live.html. The broadcasted events of workshops were watched via the internet with the appropriate software by 3500 persons, and approximately 5200 persons were listening at least one of the lectures since 1997.

Education, Medical, Continuing↗
PubMed2000

[Online literature search].

The internet offers charge-free access to electronic online databases and thus has revolutionized the handling of information. Today's challenge is the rational management of the large amount of attainable data. This overview presents the various databases--particularly databases for online Medline search--and basic knowledge for effective and successful search strategies. There are numerous important advantages of online access to literature databases: availability at any time and any place in the world, easy handling due to the user-friendly surface of the World Wide Web, capability of linking directly to the private database. Clinicians, scientists, and ophthalmologists in private practice can equally profit from the advantages of fast, easy, and charge-free online-search in medical literature databases. Literature search should thus be an important tool to obtain the latest scientific knowledge for every physician.

Databases, Bibliographic↗
PubMed2000

[Internet presence and home page design for the ophthalmologist].

An increasing number of people uses the internet for information retrieval. In the past three years nearly every University Eye Hospital provides its own information using homepages in the Internet. More and more Eye Departments and comprehensive ophthalmologists use the Internet to provide information on their own. We provide advice for the selection of a provider, use examples on how to deal with an HTML editor program and explain the technical realisation of the own Internet presence. Legal circumstances and strategies to promote the own homepage are discussed.

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