No description available.

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 104-109).

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Orientador: Vital Paulino Costa / Tese (doutorado)- Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T22:24:08Z (GMT). No. of bitstreams: 1 Silva_MarceloJordaoLopesda_D.pdf: 4720767 bytes, checksum: e65a7faa1b4b7b160cef41acf6f4b989 (MD5) Previous issue date: 2009 / Resumo: Os objetivos deste trabalho são comparar a pressão intra-ocular (PIO), medida com tonometria de contorno dinâmica (TCD) e tonometria de aplanação de Goldmann (TAG), analisar a influência da espessura central da córnea (ECC) e idade, em ambas as medições, bem como a influência do índice de qualidade sobre as leituras da TCD. Foram avaliados 500 indivíduos saudáveis (1000 olhos), sem história prévia de glaucoma ou hipertensão ocular (idade: 7 a 86 anos) recrutados consecutivamente. TAG, TCD e ECC foram obtidos de ambos os olhos de cada indivíduo, nessa ordem, por três observadores. A média de cinco medidas da ECC foi utilizada para análise. As medições da TCD foram aceitas quando o escore de qualidade variou entre 1 (qualidade superior) e 3 (menor qualidade). A média das PIOs obtidas com TCD foram superiores em 3,2 mmHg às medições com TAG. A análise de Bland-Altmann revelou má concordância entre as leituras de TCD e TAG, com intervalos de confiança de 95% de ± 6,98 mmHg. Os valores da ECC variaram entre 449 e 653 µm. As PIOs medidas com TAG mostraram-se fortemente correlacionadas à ECC (r? = 0,28, p <0,001), enquanto as PIOs obtidas com TCD apresentaram fraca correlação com a ECC (r2 = 0,01, p = 0,017). Tanto as medidas de TCD (r2 <0,01, p = 0,044) quanto as obtidas com TAG (r2 = 0,01, p <0,001) apresentaram fraca correlação com a idade. Os escores de qualidade das medidas de TCD foram 1 (n = 369, 36,9%), 2 (n = 340, 34,0%) e 3 (n = 291, 29,1%). As leituras de medida com TCD com escore de qualidade 3 (18,8 ± 3,4 mmHg) foram significativamente maiores do que aquelas com escore 1 (16,7 ± 2,9 mmHg) e 2 (17,4 ± 2,9 mmHg) (p <0,001). Concluiu-se que a medida com TCD não é influenciada pela ECC, ao contrário daquela com TAG. As medidas de PIO tomadas com TCD e com TAG não são influenciados pela idade. Finalmente, medidas de TCD com qualidade inferior apresentam valores maiores que as de qualidade superior. / Abstract: The purposes of this study are to compare the IOP measurements obtained with dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT), and to analyze the influence of central corneal thickness (CCT) and age on both measurements, and the influence of the quality score on DCT readings. 500 healthy subjects with no previous history of glaucoma or ocular hypertension (ages: 7 to 86 years old) were consecutively recruited. GAT (Haag Streit R900, Switzerland), DCT (SMT Swiss Micro Technology, Switzerland), and CCT (Sonomed Micropach 200P+, USA) measurements were obtained from both eyes of each individual, in this order, by three observers. The mean of five CCT measurements was used for analysis. DCT measurements were accepted when quality scores varied between 1 (higher quality) and 3 (lower quality). In our series, the mean DCT measurements were 3.2 mmHg higher than GAT readings. CCT values varied between 449 and 653 µm. IOP measured by GAT correlated strongly with CCT (r2=0.28, p<0.001), whereas DCT readings correlated poorly with CCT (r2=0.01, p=0.017). Both DCT (r2<0.01, p=0.044) and GAT (r2=0.01, p<0.001) measurements correlated poorly with age. Bland-Altmann analysis revealed disagreement between DCT and GAT readings, with 95% confidence intervals of ± 6.98 mmHg. Quality scores for DCT measurements were 1 (n=369, 36.9%), 2 (n=340, 34.0%) and 3 (n=291, 29.1%). DCT readings with quality score of 3 (18.77±3.35 mmHg) were significantly higher than those with quality scores of 1 (16.61±2.91 mmHg) and 2 (17.44±2.93 mmHg) (p<0.001). In conclusion, DCT is not influenced by CCT, unlike GAT. Both DCT and GAT measurements are not influenced by age. DCT measurements with lower quality scores are associated with higher readings. / Doutorado / Doutor em Ciências Médicas

The principal work in this thesis describes the investigation of the impact that alterations to ocular aberrations following refractive surgery have on the accommodative mechanism. A series of prospective studies were conducted with healthy adults (n=36) that had chosen to undergo refractive surgery at Manchester Royal Eye Hospital. A variety of monocular accommodative functions were assessed prior to surgery and then at one and three months following surgery on the same cohort of patients. Accommodative functions included amplitude of accommodation, accommodative facility (at 6m and 0.4m) including positive and negative response times, and accommodative stimulus-response functions. Dynamic accommodation responses were examined in a subgroup (n=10) at three months following refractive surgery and compared to an age-matched emmetropic control group (n=10) to evaluate differences in latency, amplitude, time constant and peak velocity of accommodation and disaccommodation. During the studies, ocular aberrations were concurrently measured to determine whether alterations to aberrations could help explain any observed changes in accommodative functions. Evaluation of visual, refractive and questionnaire outcome measures indicated that the patient cohort underwent successful surgery. Following surgery, significant alterations to a number of accommodative functions were discovered. Mean subjective ocular amplitude of accommodation increased by approximately 0.50D (p<0.05), mean stimulus-response function gradient decreased by approximately 10% (p<0.05) and distance facility rate increased by approximately 2-3 cycles/minute (p<0.05). Significant correlation was found between the change in accommodative stimulus-response function gradient, and the change in spherical aberration following surgery (p<0.05). Significant differences were also found in the parameters of accommodative dynamics, although some of these factors may be explained by refractive error differences between the refractive surgery patients (pre-operative myopes) and the emmetropic control group. The results suggest that alterations to aberrations following refractive surgery may be capable of influencing elements of the accommodation response. Additional studies were conducted to investigate the changes in aberrations during accommodation (n=31 subjects), and explore the contribution of the tear film (n=19 subjects) to higher order aberrations in eyes that have undergone refractive surgery. The results suggested that the rate of change in aberrations during accommodation is not affected by refractive surgery, but that the pattern of aberrations induced by post-blink tear film changes may differ in patients that have undergone refractive surgery. A further study is presented which investigated the form of the accommodative stimulus-response function to grating target of different spatial frequencies in groups of myopic (n=10) and emmetropic (n=10) participants recruited from among the staff and students at The University of Manchester. Both refractive groups appeared to show similar accommodative behavior, however the dominant feature of the data in both groups was between subject variation.

No description available.

No description available.

No description available.

No description available.

CD4+ T cells can be subdivided on the basis of their lymphokine repertoire produced on activation resulting in TH1 like and TH2 like populations. The purpose of this study was to measure the intraocular expression of cytokines as a means of defining the CD4+ lymphocyte subsets present during the development of uveoretinitis. Lewis rats were immunised with retinal antigen and pertussis toxin resulting in early signs of disease activity evident by day 9 with increasing severity evident by day 12. Extensive clinical and histological damage was observed by day 14 with a reduction in severity through to end stage disease at day 24. In this study, the failure to establish pure populations of retinal antigen specific T lymphocyte cell lines and the observation of the lack of sensitivity of Northern hybridization to signals expressed at low levels resulted in the more sensitive technique of RT-PCR being utilized. Both IL2 and IFN mRNA expression was detected at all stages of disease with highest levels being present early in uveitis. In contrast IL4 mRNA levels increased with disease progression. This study suggests a pathogenic role for TH1 like cells and a protective role for TH2 like cells in this autoimmune disease. In order to provide an insight into alternative treatment strategies of the disease, immunomodulation of EAU was carried out using the immunosuppressive drugs CsA, FK506 and rapamycin and the resultant cytokine mRNA profiles examined. The results indicated that CsA and FK506 downregulated the TH1 response having suppressive effects on the levels of IL2 and IFN mRNA respectively. In contrast rapamycin was found to modulate the TH2 response enhancing IL4 levels. From this data, a drug based strategy employing rapamycin appears to be the most favourable approach.