Hochschule für Technik und Umwelt FHNW
Dauerhafte URI für den Bereichhttps://irf.fhnw.ch/handle/11654/35
Listen
6 Ergebnisse
Bereich: Suchergebnisse
Publikation Does air gas aesthesiometry generate a true mechanical stimulus for corneal sensitivity measurement?(Wiley, 01.03.2018) Nosch, Daniela; Pult, Heiko; Albon, Julie; Purslow, Christine; Murphy, Paul JAim of this study - to determine: (A) the stimulus temperature inducing no or least change in ocular surface temperature (OST), using the Belmonte Ocular Pain Meter (OPM); and (B) to evaluate if OST remains unchanged with different stimulus durations and airflow rates. A total of 14 subjects (mean age 25.14 ± 2.18 years) participated: (A) OST was recorded using an infrared camera (FLIR A310) during the presentation of airflow stimuli, at five temperatures, ambient temperature (AT) +5°C, +10°C, +15°C, +20°C and +30°C, using the OPM; and (B) OST measurements were repeated with two stimulus temperatures (AT +10°C and +15°C) while varying stimulus durations and airflow rates. Results: (A) Stimulus temperatures of AT +10°C and +15°C induced the least changes in OST (-0.20 ± 0.13°C and 0.08 ± 0.05°C). (B) OST changes were statistically significant with both stimulus temperatures and increased with increasing airflow rates (p < 0.001).01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Relationship between corneal sensation, blinking, and tear film quality(Lippincott Williams & Wilkins, 17.05.2016) Nosch, Daniela; Pult, Heiko; Albon, Julie; Purslow, Christine; Murphy, Paul JPurpose. To examine the possible role of corneal sensitivity and tear film quality in triggering a blink by investigating the relationship between blink rate, central corneal sensitivity threshold (CST), ocular surface temperature (OST), tear meniscus height (TMH), tear film quality (noninvasive tear break-up time [NIBUT]), and tear film lipid pattern under normal conditions. Methods. Fortytwo volunteers (average age 27.76+/-5.36 years; 11males) with good ocular health( OcularSurfaceDisease Index, <15.0) were recruited for this cross-sectional cohort study. Blink rate, CST (noncontact corneal air gas aesthesiometry, NCCA), minimum and maximum OST in the central and inferior cornea between blinks (thermal infrared camera), TMH, NIBUT, and lipid pattern of the tear film (Keeler Tearscope Plus) were recorded on the right eye only. Results. Median blink ratewas 11blinks/min (interquartilerange [IR], 6.95 to 17.05), CST was 0.35mbars (IR,0.30to0.40), minimum OST in the central cornea was 35.15°C (IR, 34.58 to 35.50), and NIBUT was 34.55 s (IR, 12.45 to 53.80). Moderate but statistically significant correlations were observed between CST and NIBUT (r = 0.535, p < 0.001), CST and blink rate (r = -0.398, p < 0.001), lipid pattern and OST (r = 0.556, p < 0.001), and between CST and OST (r = 0.371, p = 0.008). The correlations between blink rate and NIBUT (r = -0.696, p < 0.001) and between OST and NIBUT (r = 0.639, p G 0.001; Spearman test) achieved higher significance; this was highlighted by the linear regression model where NIBUT and minimum central and inferior OST were identified as significant predictor variables. Conclusions. There is strong evidence for significant interactions between corneal sensitivity, NIBUT, OST, and blink frequency, emphasizing that ocular surface conditions represent a possible important trigger for the initiation of a blink. However, the mechanisms involved in the initiation of a blink are complex, with local ocular sensory input as only one trigger, along with other external influences and internal factors under cortical control.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Blink animation softare to improve blinking and dry eye symptoms(Lippincott Williams & Wilkins, 09/2015) Nosch, Daniela; Foppa, Curdin; Toth, Mike; Joos, Roland E.Purpose: To evaluate if the animation “blink blink” increases blink rate and improves dry eye symptoms during prolonged computer use. Methods: Study part A: Blink rate was recorded at baseline and during computer work of normal subjects without symptoms of dry eye. Half of the subjects used “blink blink,” instructed to blink on animation appearance; the other half used a placebo version for 1 week during computer use. Thereafter, blink rate was recorded again with the use of “blink blink.” Study part B: Blink rate was recorded during computer work with dry eye symptoms (modified Ocular Surface Disease Index > 15.0). Subjects used the test and placebo version of “blink blink” each for 1 week (1 week washout; crossover) and were instructed to blink twice on presentation of the animation. Blink rate and dry eye symptoms were assessed after each phase and compared with baseline. Results: Study part A: Ten subjects participated (mean [±SD] age, 38.3 [±16.0] years; 5 women). A greater increase in blink rate was observed in the test group (5.62 blinks/min for the test group and 0.96 blinks/min for the control group). Study part B: Twenty-four subjects participated (mean [±SD] age, 39.3 [±19.1] years; 11 women). Dry eye symptoms improved during both phases (with test and placebo) to a statistically significant degree (each, p < 0.001). This difference was more marked with the test (−5.42 [±2.86] points) compared with the placebo version (−1.79 [±1.38] points). Blink rate increased with the program by 6.75 (±3.80) blinks/min (p < 0.001), compared with 0.50 (±2.83) blinks/min with placebo (p = 0.396). This difference between test and placebo was statistically significant (p < 0.001). Twenty of the 24 subjects could tolerate “blink blink” well during computer use. Conclusions: Blink rate and dry eye symptoms improved with “blink blink.” The double blink prompted by the animation allowed a decrease in number of presentations and improved acceptance of “blink blink.”01A - Beitrag in wissenschaftlicher ZeitschriftPublikation The application of a computerised videokeratography (CVK) based contact lens fitting software programme on irregularly shaped corneal surfaces(Elsevier, 09/2007) Nosch, Daniela; Mavrikakis, Ioannis; Morris, Judith; Ong, Gek L.Purpose: To explore the success of the application of a computerised videokeratography (CVK) software system for the fitting of rigid gas permeable (RGP) contact lenses (CLs) on irregular corneal surfaces and compare it to the standard diagnostic fitting procedure. Methods: This was a comparative prospective study, over a 1-year period (2004–2005). It included 41 RGP CL wearers (68 eyes) with irregular corneal surfaces. Of these, 51 (75%) had keratoconus, 7 (10%) corneal scarring (infectious or traumatic), 6 (6.82%) corneal transplants, 2 (2.9%) astigmatism, and 2 (2.9%) aphakia. Each eye was being re-fitted with a new RGP CL based on a topographical measurement in conjunction with a CL fitting software programme. The performance of the CLs was evaluated regarding visual outcome, fitting characteristics, and efficiency of the fitting procedure. Results: Of the 68 eyes, 53 (77.94%) chose the CL fitted using the CVK software system, 9 (13.24%) chose the CL fitted using the standard procedure, and 6 (8.82%) showed no preference for either CL. There was a statistically significant improvement regarding visual outcome [contrast sensitivity at the spatial frequencies of 0.66 ( p = 0.029), 3.40 ( p = 0.008), and 17 ( p = 0.032), subjective vision ( p = 0.009)], fitting characteristics [grading scale ( p = 0.00), lens comfort ( p = 0.00) and daily wearing time ( p = 0.002)], and efficiency [number of trial lenses required ( p = 0.00)] with the CL fitted using the CVK software system. Correlating factors for the likely preference for the CL fitted using the CVK software system were subjective vision ( p = 0.004), lens comfort ( p = 0.009), and convenience of the fitting procedure ( p = 0.023). Conclusion: The application of a CVK software system for the fitting procedure of RGP CLs on irregular corneal surfaces was a safe procedure and shown to be more successful and efficient than the standard diagnostic fitting method.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Contact Lens profile: a tale of two countries(Elsevier, 12/2009) Bowden, Tim; Nosch, Daniela; Harknett, TonyIntroduction: This study investigated the modality, type and duration of contact lens wear as well as compliance and hygiene related issues (hand and case hygiene, use of tap water, dozing and overnight wear) in the UK and Germany. Questionnaires were collected anonymously from 417 UK and 767 German patients attending optometric practices for contact lens appointments. It is the seventh of a series of contact lens wearer profiles conducted since 2000. Results: The proportion of rigid gas permeable lenses worn was significantly higher at 55.4% in Germany, compared to 16.1% in the UK. Overall, a significantly larger proportion of German participants used tap water to rinse their lenses and cases (P < 0.001). Also, German respondents changed their lens cases less frequently (p < 0.001). Fewer UK than German respondents stated they washed their hands before lens insertion (p = 0.009), removal (p = 0.01), before eating (p < 0.001). German participants were less likely to wash their hands before preparing food (p = 0.042) and after using the toilet (p = 0.002). The two sample groups differed significantly regarding the care regimens they used for their CLs (p < 0.001). Conclusion: The differences between Germany and the UK highlighted in this study were caused by differences in legal regulations, plumbing and practitioners’ guidance. Although many of the questions relating to hygiene differed statistically between the two participating sample groups, the absolute differences in figures were not considered to be large.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Dynamic contour tonometry (DCT) over a thin daily disposable hydrogel contact lens(Elsevier, 2010) Nosch, Daniela; Herrmann, Didier; Duddek, Armin P.; Stuhrmann, Oliver M.Dynamic Contour Tonometry (DCT) has been shown to measure the intraocular pressure (IOP) independent of corneal physical properties such as thickness, curvature and rigidity. The aim of this study was to find out if DCT remains accurate when it is applied on regularly shaped corneas while a thin, daily hydrogel contact lens (CL) is worn. Methods: This was a prospective, randomised study and included 46 patients (46 right eyes): 26 females and 20 males. The age varied from 22 to 66 years (mean: 43.0±12.70 years). IOP and ocular pulse amplitude (OPA) measurements were taken with and without a daily disposable hydrogel CL (−0.50 D), Filcon IV) in situ (using the DCT), with a randomised order of measurements. Results: The average value for the IOP measurements without CL was 16.51±3.20mmHg, and with CL in situ it was 16.10±3.10mmHg. The mean difference was 0.41mmHg and not found to be statistically significant (p = 0.074). The average value for the OPA measurement without CL was 2.20±0.79mmHg. With CL in situ it was 2.08±0.81mmHg. This gave a mean difference of 0.11mmHg and was statistically significant (p = 0.025). The Bland–Altman plot showed a maximum difference in IOP of +2.44 and −2.00mmHg (CI 0.95). Regarding OPA, the maximum difference was +0.81 and −0.60mmHg (CI 0.95). Conclusion: The presence of a thin hydrogel CL did not affect the accuracy of IOP measurements using the DCT. The ocular pulse amplitude was measured on average 5.45% lower with a CL in situ.01A - Beitrag in wissenschaftlicher Zeitschrift