Biomedical subjects

Wolfgang Radner

Publications and source records attributed to Wolfgang Radner.

14 recordsLinked to original sources

PubMed2006

Reading performance of patients with uveitis-associated cystoid macular edema.

PURPOSE: To evaluate the extent of the visual impairment caused by uveitis-associated cystoid macular edema (CME) and compare the results with lesion size. DESIGN: Observational case series. METHODS: setting: Uveitis outpatient clinic of the Department of Ophthalmology and Optometry, Medical University of Vienna. patient population: CME was verified in 30 eyes of 30 consecutive uveitis patients with optical coherence tomography and lesion size was assessed with retinal thickness analyzer. main outcome measures: Distance visual acuity (VA) (measured with Early Treatment Diabetic Retinopathy Study charts), reading acuity, and reading speed (tested with Radner Reading Charts). Results were compared with nonaffected partner eyes. RESULTS: Distance VA was logMAR 0.22 +/- 0.15 in CME eyes vs -0.02 +/- 0.17 in healthy controls. Reading acuity was 75% of logMAR in CME eyes vs 92% of logMAR in control eyes (P = .01). The mean reading speed was 148.4 +/- 36.6 words per minute in patients with CME vs 168.9 +/- 36.3 in patients without CME (P = .04). Reading acuity correlated with both lesion size and distance VA (r = 0.61; P = .01 and r = 0.53; P = .028, respectively). Neither anatomical classification of uveitis nor gender or age had a significant influence on the evaluated parameters. CONCLUSIONS: Reading acuity and reading speed were considerably more impaired than distance visual acuity. The assessed parameters showed a better correlation to lesion size and seem to be a better reflection of macular dysfunction. Analyzing reading function is an important factor when following patients with CME and evaluating success of treatment modalities.

Adolescent↗

PubMed2005

Differences in reading performance of patients with Drusen maculopathy and subretinal fibrosis after CNV.

PURPOSE: To evaluate differences in reading performance and contrast sensitivity on patients with drusen maculopathy and subretinal fibrosis after CNV (choroidal neovascularisation). METHODS: 136 patients (60 with drusen (D), 76 with fibrosis (F)) were studied. Patients were classified according to type of maculopathy and best-corrected visual acuity into groups D1 and F1 (LogMAR 0.2-0.4), groups D2 and F2 (LogMAR>0.4-0.7), and group F3 (LogMAR>0.7-1.3). Reading acuity (in LogRAD) and speed were examined with the Radner Reading charts and compared to the reading speed measured with the long paragraphs of the Zuercher Reading Test. Contrast sensitivity was measured with Pelli-Robson charts. RESULTS: The patients' distance visual acuity was comparable between the drusen and fibrotic CNV groups (D1 versus F1, D2 versus F2). The reading acuity of the corresponding groups D1 and F1 was also comparable, but F2 patients showed a statistically lower reading acuity than D2 patients (P=0.03). All reading speed measurements of the groups F1 and F2 were significantly worse than those of the corresponding groups D1 and D2 (P-values: 0.0005-0.02). The correlation of reading speed between the Radner and Zuercher texts was very high (r=0.73-0.94). The contrast sensitivity was significantly lower in all groups compared with group D1 (P<0.001), but comparable for groups F1, F2, and F3. CONCLUSIONS: Despite comparable results in distance visual acuity, patients with subretinal fibrosis after CNV had a greater reduction in reading ability than the patients with drusen. The distance visual acuity measurements alone, therefore, underestimate the real-life conditions and impact of AMD.

Aged↗

PubMed2005

Influence of laser in situ keratomileusis and laser epithelial keratectomy on patients' reading performance.

PURPOSE: To evaluate the influence of laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK) on reading performance regarding reading acuity, reading speed based on print size, maximum reading speed, and critical print size. SETTING: Department of Ophthalmology, University of Vienna, Vienna, and Auge-und-Laser, Medicent Baden, Austria. METHODS: Fifty-two eyes of 34 patients (26 eyes per group) were studied. Best corrected LogMAR visual acuity (Early Treatment Diabetic Retinopathy Study charts), reading acuity, and reading speed were tested monocularly before LASIK or LASEK and 3 weeks after surgery. Reading acuity (LogRAD) and reading speed were determined with the standardized Radner reading charts. RESULTS: Preoperatively, the distance visual acuity and reading acuity were comparable between the LASIK and LASEK patients. Reading speed measurements also showed no statistical difference. Three weeks after refractive surgery, no statistically significant differences in the preoperative measures and between the 2 surgical procedures could be found in any tested parameters. The mean distance visual acuity was LogMAR -0.02 +/- 0.06 (SD) (LASIK) and LogMAR -0.05 +/- 0.07 (LASEK). The mean reading acuity was LogRAD 0.00 +/- 0.12 (97.7% of LogMAR) (LASIK) and LogRAD 0.04 +/- 0.16 (93.7% of LogMAR) (LASEK). The mean maximum reading speed was 235 +/- 35 words per minute (LASIK) and 240 +/- 37 words per minute (LASEK), and the mean critical print size was at LogRAD 0.48 +/- 0.19 (LASIK) and 0.49 +/- 0.17 (LASEK). CONCLUSIONS: In a standardized reading test setting, no significant effects of LASIK and LASEK on individual reading performance could be evaluated. This indicates that patients can expect to retain their normal visual function after refractive surgery with these 2 procedures under full light conditions.

Adult↗

PubMed2005

Discriminative power of reading tests to differentiate visual impairment caused by cataract and age-related macular degeneration.

PURPOSE: To determine whether preoperative reading tests can be used for differentiating visual impairments with regard to the diagnosis of cataract and age-related macular degeneration (ARMD). SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: Reading performance of patients with nuclear cataract, posterior subcapsular cataract, and ARMD were evaluated with respect to reading acuity, maximum reading speed, and critical print size; normal-sighted participants were tested as controls. A multivariate discriminant analysis of the 4 groups (100 eyes of 100 participants) was performed to evaluate how many patients could be correctly diagnosed by significant differences in the tested reading parameters. Subsequently, the nuclear cataract and posterior subcapsular cataract patients were compared with cataract patients with coexisting ARMD. RESULTS: Distance visual acuity was comparable in the nuclear cataract, posterior subcapsular cataract, and ARMD groups (P>.05). Reading acuity was significantly reduced in posterior subcapsular cataract and ARMD patients compared with nuclear cataract patients and controls (P<.0001). No significant difference in maximum reading speed was found between the nuclear cataract patients and the controls (P = .07), whereas the maximum reading speed of the posterior subcapsular cataract and ARMD patients was significantly reduced (P<.0001). In the discriminant analysis, it was possible to assign the correct diagnosis to 72% of the nuclear cataract patients, 76% of the posterior subcapsular cataract patients, 72% of the ARMD patients, and 92% of the controls. Comparing the reading performance of nuclear cataract and posterior subcapsular cataract patients and cataract patients with coexisting ARMD showed that reading performance was significantly impaired in the comorbid patients (nuclear cataract and ARMD, P<.001; posterior subcapsular cataract and ARMD, P<.05). CONCLUSION: The high discriminant accuracy shows that this standardized reading test system is a valuable diagnostic tool for evaluating functional visual impairments when distance visual acuity alone cannot elucidate the origin of functional impairment. Considering the significant discrepancies in reading performance among patients with nuclear cataract, posterior subcapsular cataract, and ARMD, reading tests may relevantly improve the clinical evaluation of patients with visual loss, even of patients with ocular comorbidity.

Aged↗

PubMed2004

Proliferative vitreoretinopathy--at what risk is the fellow eye?

PURPOSE: To find out if patients with proliferative vitreoretinopathy (PVR) due to complicated retinal detachment are at risk to acquire the same disease or other vision-threatening retinal abnormalities in the fellow eye. To furthermore assess in what time-period they appear and if subgroups of patients have special risks. METHODS: 100 consecutive PVR-patients were studied retrospectively. 21 patients with PVR graded lower than C3, traumatic PVR, diabetic retinopathy or congenital vitreoretinal diseases were excluded. Age, gender, best-corrected visual acuity at the first and last visit, refraction, ocular disease in both eyes and observation-time were recorded. RESULTS: After a mean follow-up of 8.5 years, 42 of 79 patients (53.4%) showed vision-threatening abnormalities in their fellow eyes: among them, 9 patients (11.4%) had PVR, 13 (16%) simple retinal detachments and 14 (17.3%) retinal breaks. Abnormalities in the fellow eye did not develop after a certain time following surgery of the primary eye; 71.4% appeared within 5 years. Aphakic and pseudophakic patients had retinal breaks significantly more often (p = 0.011) than phakic patients. Myopia did not increase the risk for any abnormality. Men developed retinal detachment (p = 0.037) and PVR (p = 0.025) significantly more often than women. CONCLUSION: Patients with PVR have a greater than 50% risk of developing vision-threatening retinal abnormalities in their fellow eye. Because of this increased risk, these patients need regularly-scheduled long-term follow-up. SUMMARY STATEMENT: Patients with PVR have a greater than 50% risk of developing vision-threatening retinal abnormalities in their fellow eye and a 37% risk to develop PVR from rhegmatogenous retinal detachment. More than two thirds of abnormalities in the fellow eye developed within five years of surgery of the primary eye.

Adult↗

PubMed2004

Informed consent and decision making by cataract patients.

OBJECTIVES: To investigate decision making by patients on the day before cataract surgery and to evaluate to what extent the informed consent process influences the patients' decision regarding consent. METHODS: On the day before surgery, 70 patients (mean +/- SD age, 70.3 +/- 10.3 years) underwent a standardized informed consent procedure. They were also invited to answer 15 questions established in interdisciplinary cooperation among clinical psychologists, lawyers, and ophthalmologists. MAIN OUTCOME MEASURES: We assessed presurgical information and personal estimation of risks in cataract surgery; the patient-physician relationship regarding surgery-related decisions; and evaluations of the informed consent procedure and the patients' decision. RESULTS: Questionnaire answers indicated that 28 (40%) of the 70 participating patients arrived for surgery without any information; 16 (23%) believed that there were surgical procedures without risks; and 53 (76%) estimated that there were no risks for their cataract surgery. A physician-dominated decision for surgery was preferred by 31 patients (44%); 16 (26%) wanted to decide together with their ophthalmologist. Possible risks of a sight-threatening complication did not influence 54 patients' (77%) decisions, and 55 patients (78%) said the informed consent process did not influence their decision. The remaining 15 (22%) stated that the informed consent process positively confirmed their decision. CONCLUSIONS: Informed consent 1 day preoperatively does not seem to influence the decision for cataract surgery. Cognitive dissonance as part of a decision-making process makes changes in an already chosen option unlikely. The resulting limited decisive potential is very important for credibility in a trial and has to be considered in ophthalmologic surgery.

Aged↗

PubMed2004

Reading performance depending on the type of cataract and its predictability on the visual outcome.

PURPOSE: To investigate the influence of various types of cataract on reading performance in a standardized reading test setting. SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: The reading performance of 94 eyes with age-related cataract and normal macular function was evaluated with the Radner Reading Charts preoperatively and 4 weeks after cataract surgery. Distance visual acuity was tested with the ETDRS charts. Cataracts were graded using the Lens Opacities Classification System (LOCS) III, on which NO is nuclear opalescence and NC is nuclear color. RESULTS: Patients with pure nuclear cataracts (LOCS III: NO/NC 2.1-5) achieved a normally high MRS (99.84% +/- 7.65% of their postoperative MRS): preoperative MRS(1): 190.6 +/- 30.74 words per minute (wpm); postoperative MRS(2): 191.21 +/- 29.36 wpm. Patients with mixed nuclear-cortical cataracts (LOCS III: NO/NC 2.1-5; C>2) preoperatively achieved 96.96% +/- 5.6% of their postoperative MRS (MRS(1): 175.77 +/- 31.54 wpm; MRS(2): 181.34 +/- 30.56 wpm). In dense nuclear cataracts (LOCS III: NO/NC>5), the MRS was significantly reduced, achieving only 72.64 +/- 19.19% of the postoperative MRS (MRS(1): 133.06 +/- 39.43 wpm; MRS(2): 185.76 +/- 40.18 wpm). In posterior subcapsular cataracts, the preoperative MRS (134.1 +/- 33.72 wpm) was significantly lower than postoperatively (191.14 +/- 27.08 wpm). CONCLUSIONS: In contrast to dense nuclear cataracts and posterior subcapsular cataracts, the preoperative reading speed of patients with pure nuclear or nuclear-cortical cataracts was normal at large print sizes. The preoperative evaluation of reading acuity and speed with standardized reading tests can therefore be used to estimate the postoperative reading performance in the latter 2 types of cataract.

Aged↗

PubMed2004

Tissue damage at anterior capsule edges after continuous curvilinear capsulorhexis, high-frequency capsulotomy, and erbium:YAG laser capsulotomy.

PURPOSE: To compare the effect of erbium:YAG laser photocapsulotomy (ELC), continuous curvilinear capsulorhexis (CCC), and high-frequency capsulotomy (HFC) on anterior capsule edges using light microscopy (LM) and transmission electron microscopy (TEM). SETTING: Department of Ophthalmology, Department of Histology and Embryology II, University of Vienna, Vienna, Austria. METHODS: Five anterior capsule membranes were obtained experimentally by ELC, which was performed with the Oertli MicroLaser photoemulsification tip in eyes from 5 human cadavers. Thirty anterior capsule membranes were obtained during cataract surgery by CCC (n = 15) or, in cases with poor or missing red fundus reflexes, by HFC (n = 15). Continuous curvilinear capsulorhexis was performed conventionally with a manual, bent, 27-gauge cannula, and HFC was performed according to Klöti. Membranes were processed and examined by LM and TEM according to standard procedures. RESULTS: The edges obtained by ELC showed mild signs of denaturation and mechanical disruption, tears, and micro-tears. Lens capsule edges obtained by CCC were smooth with no irregularities in any specimen; the edges were beveled anteriorly to posteriorly with no evidence of tearing. Edges produced by HFC were considerably wider; the surfaces showed distinct denaturation, preformed tears, and micro-tears. The edges were surrounded by a nonhomogeneous mass, which consisted mainly of denatured lens capsule material. CONCLUSIONS: Of the 3 techniques, CCC produced the mildest tissue damage. The histological damage at ELC edges was relatively mild and intermediate compared with that seen at CCC and HFC edges. These observations suggest that ELC is an appropriate option for anterior capsulotomy in cataract surgery.

Aged↗

PubMed2003

Reliability of a standardized reading chart system: variance component analysis, test-retest and inter-chart reliability.

BACKGROUND: The purpose of this study was to analyze statistically the test-retest and inter-chart reliability of three standardized Radner Reading Charts with respect to reading acuity, maximum reading speed, critical print size and LogRAD/LogMAR ratio and to quantitatively identify the sources of variability. METHODS: At two testing sessions (3 to 4 weeks apart), 36 volunteers read monocularly all three Radner Reading Charts in randomized order (orthogonal Latin square design). The subjects were grouped according to their distance LogMAR visual acuity (group 1, 0.1 or better; group 2, 0.12-0.4; group 3, 0.42-0.8). Based on these 216 reading tests, crude correlations were calculated between the two testing sessions and between the three charts, and "variance component analyses" were performed for all variables. RESULTS: For all visual acuity groups and variables, the test-retest and the inter-chart reliability was high. The variance component analyses showed that the differences between individuals predominantly influenced the variance, whereas the effect of the test replication was low. The three charts caused minimal variability, indicating equality for clinical examinations. CONCLUSION: The standardized Radner Reading Charts provide clinically reliable and reproducible results for individuals with normal eyesight and for patients with visual impairment. These findings indicate that reading test systems, which consider the current international standards for visual acuity measurements (EN ISO 8596, NAS-NRC) and the psychophysical requirements for controlling optical item interactions, can provide reliable measures for clinical and scientific analyses of reading performance.

Aged↗

PubMed2003

Scotoma size and reading speed in patients with subfoveal occult choroidal neovascularization in age-related macular degeneration.

PURPOSE: To investigate the correlation between reading speed and scotoma size in patients with subfoveal occult with no classic choroidal neovascularization (CNV) in age-related macular degeneration (AMD) participating at 2 of 28 centers in the Verteporfin in Photodynamic Therapy trial. DESIGN: Prospective, observational case series. PARTICIPANTS: Twenty-two eyes of 22 patients with occult with no classic CNV in AMD. METHODS: Patients' reading speed was examined using a German-language reading test (Radner Lesetest). Scotoma size was measured using the microperimetry program 2.01 of the Rodenstock Scanning Laser Ophthalmoscope. MAIN OUTCOME MEASURES: Reading acuity, reading speed, size of absolute (AS) and relative scotoma (RS). RESULTS: There was a significant correlation between the size of AS and reading speed (r = -0.48, P = 0.023), as well as AS and reading acuity (r = 0.52, P = 0.013). No correlation was seen between RS and reading speed or reading capacity. CONCLUSION: The size of absolute scotoma correlated significantly with reading capacity and reading speed and may influence these measures.

Aged↗

PubMed2002

The validity and reliability of short German sentences for measuring reading speed.

PURPOSE: To investigate whether short German sentences that have been developed to be highly comparable in number and length of words, as well as in difficulty and construction, are reliable and valid test items for measuring reading speed in order to use them for measuring simultaneously reading acuity and speed with the "Radner Reading Charts". METHODS: Tests were performed in 198 persons: 99 university students (average age 23.6+/-2.8 years) and blue-collar apprentices (average age 18.4+/-2.5 years). Reading speed and the number of errors were determined first with 24 sentences for our recently developed German reading charts (14 words equal in difficulty, length and construction) and secondly with long paragraphs of the "Zuercher Reading Test" (ZRT; paragraphs 3-5, 261 words). RESULTS: The overall mean reading speed obtained with short sentences was 209.6+/-41.0 words per minute (wpm), compared with 169.2+/-35.0 wpm for the ZRT ( P<0.001). The correlation between the short sentences and the ZRT was high ( r=0.9). Students read faster and made fewer errors than did the apprentices. Reliability analyses yielded an overall Cronbach's alpha coefficient of 0.98. The coefficient of selectivity of the 24 sentences (test items) varied from 0.75 to 0.88. CONCLUSION: The present study indicates that the 24 short single sentences we have tested are highly comparable in terms of both lexical difficulty and reading length, and it has demonstrated the validity and reliability of such sentences as test items for determining reading speed.

Adolescent↗

PubMed2002

Reading performance with a refractive multifocal and a diffractive bifocal intraocular lens.

PURPOSE: To evaluate the reading performance of a diffractive bifocal (811E, Pharmacia) and a refractive multifocal (SA40N, Allergan) intraocular lens (IOL) and compare it with that of a monofocal IOL (811C, Pharmacia) with respect to reading acuity, reading speed based on print size, maximum reading speed, reading distance, and critical print size. SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: This study comprised 120 pseudophakic eyes of 70 patients; each IOL group had 40 eyes. The patients' age, sex, and best corrected logMAR visual acuity were recorded. Reading acuity and speed were tested monocularly. Reading acuity was determined in logRAD (ie, the reading equivalent of logMAR). Patients with bifocal and multifocal IOLs read with best distance correction and patients with a monofocal IOL, with an addition of +3.0 diopters. RESULTS: The age, mean spherical equivalent, cylinder, and best corrected distance visual acuity were comparable among the 3 groups. The mean logRAD reading acuity was 0.17 +/- 0.18 (SD) in the 811E group (94.0% of logMAR), 0.31 +/- 0.13 in the SA40N group (73.2% of logMAR), and 0.24 +/- 0.22 in the 811C group (94.1% of logMAR). The reading acuity in the SA40N group was statistically significantly lower than in the 811E and 811C groups. The best reading distance was 30 cm in the 811E group and 40 cm in the SA40N group. The mean maximum reading speeds in words per minute were comparable: 187.5 +/- 26.1 (811E), 171.0 +/- 21.1 (SA40N), and 179.4 +/- 21.6 (811C). The reading speed, which ranged from logRAD 0.7 to 0.3, and the critical print size in the SA40N group were significantly worse than in the 811E and 811C groups. The mean critical print size in the 811E group was significantly worse than in the 811C group. CONCLUSIONS: Reading performance was acceptable in the bifocal and multifocal IOL patients, with the diffractive bifocal IOL performing best in a standardized reading test setting.

Aged↗

PubMed2002

Interlacing of collagen lamellae in the midstroma of the human cornea.

PURPOSE: To investigate by means of scanning electron microscopy (SEM) the interlacing of collagen lamellae in the midstroma of the human cornea after opening the interlamellar spaces. MATERIAL AND METHODS: For SEM, cells and noncollagenous extracellular matrix were removed with 10% sodium hydroxide. Specimens were dehydrated in a series of graded tertiary butanols, frozen at -24 degrees C and dried in an exsiccator by sublimation of the frozen butanol. Dried corneas were cut vertically with a razor blade, and the interlamellar spaces were exposed by stretching the stroma along its anterior-posterior axis by pulling apart the inner (endothelial) and outer (epithelial) edges. Specimens were sputtered with gold and examined with a Cambridge Stereoscan 90 microscope. RESULTS: The opened interlamellar spaces gave the stroma at the cutting edge the appearance of a polymorphic honeycomb. The stromal openings differed in size, from approximately 10 microm to over 150 microm length and up to 80 microm in height. Adjacent lamellae remained connected at several interconnecting regions, either through an exchange of short merging sublamella or single fibrils. Interlacing lamellae crossed through fissures between the branches of splitting lamellae. Others crossed clefts of neighboring lamellae, and other lamellae tunneled crosswise through a horizontally split lamellae hanging in the inferior branch as in a hammock. Large interweaving zones in which a mixture of several types of interlacing was localized close together could also be found. CONCLUSION: The current study indicates that interlacing is a distinct and important feature of the human cornea, and it gives new insights into the stromal morphology by demonstrating various types of interlacing that occur between collagen lamellae.

Aged↗

PubMed2002

Increased spontaneous retinal ganglion cell activity in rd mice after neural retinal transplantation.

PURPOSE: To study the functional success of neural retinal transplantation by means of retinal surface ganglion cell recordings. METHODS: Eight-week-old C3H/HeJ (rd/rd) retinal degeneration mice received transplants (subretinal) in one eye only of neural retinal tissue isolated from newborn normal C57/BL6J mice. Four weeks after transplantation, ganglion cell responses were recorded directly from the retinal surface over the transplant, with a differential bipolar surface electrode. Measurements were performed, both with and without light stimulation. Similar recordings were performed in nontransplant areas of the transplant-recipient eyes, and in age-matched sham-treated and untreated control eyes. After the recordings, the eyes were processed for light and transmission electron microscopy. RESULTS: Histologic examination showed that in some areas, transplanted cells were organized into small sheets and differentiated into photoreceptors with outer segments in intimate contact with the host RPE. No light-driven ganglion cell responses were recordable from the transplant-recipient or control eyes. However, the spontaneous ganglion cell activity was higher in the transplant areas (mean: 10.8 +/-12.0 spikes/1.6 sec) compared with nontransplant areas of these recipient eyes (mean: 2.4 +/- 5.7spikes/1.6 sec; P < 0.001), sham-treated eyes (mean: 2.5 +/- 4.8 spikes/1.6 sec; P < 0.001), and the untreated control eyes (mean: 2.2 +/- 4.4 spikes/1.6 sec; P < 0.001). CONCLUSIONS: Subretinal transplantation of neural retinal tissue results in a local increase of spontaneous ganglion cell activity. The increased activity may be due to the release of neurochemically active substances as a result of the presence of the transplant. Although light responses were not recordable, the technique of retinal surface ganglion cell recording may be useful for assessing the functional success of transplantation.

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