Navegando por Assunto "Oftalmologia"

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Acesso aberto (Open Access)
Avaliação da razão sinal ruído em eletrorretinografia multifocal: descrição do método e aplicação em toxoplasmose ocular
(Universidade Federal do Pará, 2009) CARVALHO, Aline Correa de; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; SILVEIRA, Luiz Carlos de Lima; http://lattes.cnpq.br/9383834641490219
The purpose of this work was to develop a quantitative analysis that allows, in healthful and patient with visual loss, to separate registers with signal correlated with the visual stimulation, of the registers that contain noise. System VERIS Science v6.0.5d was used to extract kernel first-class of the registers, and posterior exportation of the data for analysis in the MATLAB. In this environment of programming was carried the analysis of the main components (PCA), that is used to reduce the dimensionalidad of the data conserving its variation and minimizing the influence of the noise; the signal-to-noise analysis (SNR) of the multifocal responses (mfERG) using cumulative distribution SNR carried through in two intervals of time, one understanding only the signal and another one only the noise, for classification of the valid, diminished or absent responses. We have found that in a group healthy subjects, the noise and signal SNR cumulative distributions have not overlapped and occupy distinct ranges of SNR values in all subjects. By using a 1% criterion for false positives and false negatives, it was possible to define the borders of noise, low response, and signal SNR ranges. We have also applied this protocol to a three subject with visual loss due to ocular toxoplasmosis scares. In this case, there was a degree of overlapping between the noise and signal SNR distributions. It was still possible to separate the noise, low response, and signal SNR range by using the confidence limits for the distance between noise and signal boundaries obtained from the group of healthy subjects. The results of SNR evaluation were then used to display the mfERG waveforms in topographical plots that discriminate between reliable responses (signal), low responses, and no responses (noise). Using this approach, features of retinal topography, such as the optic nerve head, are more easily discriminate, whilst artifacts such as an erroneous central peak, are more easily rejected. The combinations of PCA to reconstruct mfERG waveforms with SNR evaluation are useful tools to analyze retinal topography both in healthy and impaired conditions.
Acesso aberto (Open Access)
Eletrorretinografia multifocal: desenvolvimento de método avaliativo e aplicação em pacientes com toxoplasmose ocular e investigação funcional da função retiniana em pacientes com malária, infectados pelo P. Vivax
(Universidade Federal do Pará, 2014-11-03) CARVALHO, Aline Correa de; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; SILVEIRA, Luiz Carlos de Lima; http://lattes.cnpq.br/9383834641490219
The current thesis was composed by two studies performed in parallel. The first purpose was the development of a reliable method to classify the electroretinographic responses and to validate this method in ocular toxoplasmosis. The second purpose was to investigate the effect of the acute use of chloroquine in the retina of vivax malaria patients, which received the standard treatment of the Ministry of Health of Brazil. The experimental tool of both studies was the multifocal electroretinogram (mfERG). In the first study the Veris system was used to test 10 healthy subjects to calculate a signal to noise ratio analysis in order to find the best values to separate normal responses from impaired retinal responses. The final results of this analysis were applied in three patients with visual loss due ocular toxoplasmosis. The results showed an optimal signal to noise ratio of 0.47 to separate waveforms with and without signal. The signal to noise ratio of 0.47, 0.44, 0.48, 0.57, 0.78, 1.21 were optimal to separate normal responses from progressively attenuated responses. The application of the signal to noise ratio analysis into ocular toxoplasmosis patients was able to map the retinal area with no activity evoked by the light. The second study was performed using mfERG to evaluate 48 vivax malaria patients which received chloroquine-based treatment. Their data were compared to 37 healthy subjects. The results showed that number of infections ranged between from 01 to 18 times. During the treatment, the mean dosage of intaken chloroquine was 5429 ± 782.3 mg. The cumulative dosage normalized to the body mass ranged from 14.58 to 545.45 mg/kg. No difference was observed in the mfERG amplitude and implicit time obtained from malaria patients and control group at any concentric rings of the visual field. There was no significant correlation between the retinal activity with the chloroquine cumulative dosage. It was concluded that the signal to noise analysis developed in this thesis can be used as a reliable method to study impaired retinal function, including the mapping of ocular toxoplasmosis consequences; and the acute use of chloroquine for malaria treatment caused no impairments to retinal activity recorded by mfERG.
Acesso aberto (Open Access)
Life quality assessment of patients after phacoemulsification or extracapsular cataract extraction
(2014-02) MENDONÇA, Paula Teixeira de; MENDONÇA, Leonardo Teixeira de; ROSA, Alexandre Antonio Marques; SILVEIRA, Luiz Carlos de Lima
Purpose: To study the quality of life, treatment outcomes, and satisfaction in patients who have undergone cataract surgery Methods: This comparative case series study was conducted at the Ophthalmology Service of the Bettina Ferro de Souza University Hospital, Belém, Pará, Brazil. Totally, 60 patients with cataract were included; 50% underwent conventional extracapsular cataract extraction (ECEE) and 50% underwent cataract extraction by phacoemulsification (PHACO). Patients were interviewed using the Visual Function 14 (VF-14) questionnaire to determine the quality of life before and 30 days after surgery. The results of ophthalmological examination were recorded in the patients' files and were available throughout this study. One-way ANOVA, Tukey's post-hoc comparison, and the sign test were used for statistical analyses. Results: The mean VF-14 satisfaction index was 38.0 and 89.4 before and after surgery, respectively, for the ECEE group and 47.0 and 94.1, respectively, for the PHACO group. The improvement in patient quality of life after surgery was significant in both groups (p<0.0001), with a similar amount of improvement in both groups. Conclusions: The observed improvement in quality of life was significant (p<0.0001) and directly related to patient satisfaction with surgical outcomes, which was also significant (p<0.0001) as assessed using the VF-14. Satisfaction and quality of life are individual factors; consequently, patient responses to questions regarding improvements in the ability to perform each activity are subjective and depend uniquely on individual perception.
Acesso aberto (Open Access)
Manifestações retinianas em pacientes portadores de anemia de células falciformes
(Universidade Federal do Pará, 2011-10) ALMEIDA SOBRINHO, Edmundo Frota de; SARAIVA FILHO, João Carlos de Pina; SILVA, James Nunes da; SILVA, Ana Paula Siqueira da; LIMA, Rafaela Cavalcante de
The World Health Organization counts that more than 5% of the world's population carry some type of hemoglobinopathy. Among them we find the sickle cell aneamia that presents its main harmful effect on the peripheral vasculature. In the retina, the falciform lesions have a well defined physiopathology and classification. To identify the retinal manifestations caused by the falciform aneamia in patients directed to the Bettina Ferro de Souza Hospital from the Hemocenter of the State of Pará – HEMOPA, in the months of September through December of 2006. METHODS: Ophthalmologic examination was performed in the Department of Ophthalmology of the Bettina Ferro de Souza Hospital. and fifty patients with sickle cell aneamia (SS or SC) followed by the department of falciform aneamia of the Hematologia e Hemoterapia do Pará - HEMOPA have been randomly selected and submitted to interview in order to register their: sex; age; color; genotype; ocular alterations; medicines taken. Ophthalmologic examination was performed in the Department of Ophthalmology of the Bettina Ferro de Souza Hospital. It consisted of: evaluation of the acuity of vision with and without correction, indirect biomicroscopy, indirect binocular ophthalmoscopy, and, in case the latter presented alterations, a complementary study witangiofluoresceinography would be carried through. RESULTS: The outcomes have been registered in research protocol and later submitted to the statistic analysis using the Qui-square test, adopting, as level of significance, p<0,05. Eighty-eight percent of the patients did not present any falciform retinal sign, 3% presented peripheral vascular occlusion; in 2%, pigmented plate was shown, and 7% presented injuries which were not compatible with the falciform disease; there was a proportionality of 50% for males and females; there was a higher predominance (38%) of people aged from 11 and 15; 74% had SS genotype and 26% SC genotype; in relation to the use of medicines there was a higher prevalence of ocular alterations in patients who had made use of the folic acid isolated, with 5%, in contrast with those who had used the hidroxyurea association and folic acid, when all (27%) presented normal fundoscopic examination; all the patients (29%) that showed fetal hemoglobin rate above 10% had retina without alterations. CONCLUSION: Few cases of retinal signs have been observed in the studied group, however this research does not diminish the importance of early and periodic ophthalmologic examination, since falciform retinopathy is largely registered and its complications can lead to amaurosis.
Acesso aberto (Open Access)
Relação entre a biometria ultra-sonográfica em modo B do bulbo ocular e os diâmetros fronto occiptal e bizigomático em Canis familiaris
(2009-04) CARVALHO, Poliana Silva Beserra; SALES, Gustavo Aguiar; SANTANA, Expedito Junior de Matos; MIRANDA, Stefânia Araújo; BRITO, Adriel Behn de; NIKOLAK, Elizabete; DOMINGUES, Sheyla Farhayldes Souza
In the experiment 31 healthy mongrel dogs, 8 months to 7 years of age, were used, 10 males and 21 females, weighing 1.5-28 kg. Initially, fronto-occipetal (FOD) and bizigomatic (BZD) diameters were measured using a caliper. The ophthalmologic transpalpebral B-mode ultrasonography (US) was performed to measure the ocular bulbi structures, as follows: The cornea thickness (D1), distance between cornea and anterior lens capsule (D2), distance between cornea and posterior lens capsule (D3), lens thickness (D4), lens diameter (D5), lens area (D6), distance between posterior lens capsule and retina (D7), distance between anterior lens capsule and retina (D8), and the distance between cornea and retina (D9). Except for D4, there were effect of FOD and BZD on the measures of the internal structures of BO. The Lineal Regression Analysis between the measures of the internal oculars structures and DFO and DBZ were significant for D1, D2, D3, D4, D5, D6, D7, D8 and D9.
Acesso aberto (Open Access)
Retinopatia em pacientes hipertensos e/ou diabéticos em uma unidade de saúde da família
(Universidade Federal do Pará, 2014-04) ALVES, Aline Pinto; SANTOS, Reny Wane Vieira dos; ALMEIDA SOBRINHO, Edmundo Frota de; ROCHA, Sheila Patrícia Lopes; LOCH, Ana Cláudia Nóbrega
Purpose: To identify the prevalence of abnormal ophthalmoscopy in patients with systemic hypertension (SH) and / or diabetes mellitus (DM) in a Family Health Unit (FHU). Method: was performed a individual study, observational, primarily descriptive and crosssectional of a sample of a cohort of 50 patients with hypertension and / or diabetic enrolled in the program HIPERDIA in a FHU of the city of Ananindeua – Para, between the months of september and november 2009. Results: ophthalmoscopy was performed in 46 patients and 27 (58.7%) had some alteration. When performing a specific analysis (excluding the findings of arteriolar narrowing and venous engorgement) were changes in 18 (39.1%), 45.5% with DM and SH, 40% with DM and 36% with SH. Conclusion: The high prevalence of the changes in ophthalmoscopy found in this study demonstrates that effectiveness as a screening method in the context of primary health care, justifying that use. corroborates also the importance of primary care in the prevention of diabetic and hypertensive retinopathy, through periodic control of patients at high vascular risk as the population studied.