Uso da tonometria de ar em pesquisas populacionais - comparação com o tonômetro de Goldmann em indivíduos com suspeita de hipertensão ocular / Air-Puff Tonometry in population research - a comparison with Goldmann tonometer in individuals with suspected ocular hypertension

RESUMO Objetivo: Avaliar a utilidade do tonômetro de ar (TA) em estudos populacionais em indivíduos suspeitos de hipertensão ocular, comparando os valores com os fornecidos pelo tonômetro de aplanação de Goldmann (TG). Métodos: Estudo transversal, de amostra probabilística, composta por 11.452 indivíduos e"20 anos, compondo-se uma subamostra dos que apresentaram valores de pressão intraocular (PIO) obtidos com o TA e"20mmHg, nos quais a PIO foi repetida com o TG. Os resultados dos dois tonmetros foram comparados considerando sexo, cor da pele referida, lateralidade, relação escavação/disco (Â0,6; entre e"0,6 e <0,8; e"0,8) e diagnóstico. Foram consideradas três situações: não-portadores de glaucoma (NG), suspeitos (SG) e portadores de glaucoma (CG). Para comparação entre as medidas foi utilizado o teste t de Student para amostras pareadas e o teste de correlação de Pearson para avaliar a associação entre PIO, idade e tonometria. Resultados: Foram detectados 198 indivíduos (339 olhos) com PIOe"20mmHg com o TA, que tiveram a medida repetida com o TG. Foram considerados 233 olhos como NG, 47 olhos como SG e 19 olhos como CG. Em olhos com escavação e"0,8, a medida com TA e TG foram semelhantes. Nos NG e SG, o TA superestimou os valores. Houve associação entre aumento da PIO e aumento da idade com os dois tonmetros. Conclusão: Valores de PIO são superiores com TA comparados ao TG, principalmente quando a PIO é normal. Há concordância entre os métodos quando a PIO é alta e a escavação do nervo óptico é aumentada, o que valida a aplicação do TA em campanhas populacionais.

ABSTRACT Purpose: to evaluate the use of air tonometer (TA) in population studies in individuals suspected of ocular hypertension, comparing values with those provided by the Goldmann Tonometer (GT). Methods: a cross-sectional study was done using a probabilistic sample consisting of 11,452 individuals e"20 years old.A subsample composed by the individuals with IOP values obtained with TA e"20 mmHg was selected, in which IOP was repeated with the GT. The results of both tonometers were compared considering gender, referred color of skin, laterality, cup-to-disc ratio (Â0.6; e"0.6 and <0.8; e"0.8) and diagnosis, considering three situations: without glaucoma (NG), suspected glaucoma (SG) and patients with glaucoma (CG). The Student t test was used for paired samples and the Pearson correlation test to evaluate the association between IOP, age and tonometry. Results: we identified 198 individuals (339 eyes) with IOP e"20mmHg with the TA, who had the measures repeated with the GT. Two hundred and thirty-three eyes were considered as NG, 47 eyes as SG and 19 eyes as CG. In eyes with cup-to-disc ratio e"0.8, the TA and GT measurements were similar. In NG and SG, the TA overestimated values. There was an association between increased IOP and increasing age with both tonometers. Conclusion: IOP values are higher with TA compared to GT, especially when IOP is normal.There is agreement between the methods when IOP is high and the optic nerve excavation is increased, which validates the application of TA in population campaigns.

Investigation of intraocular pressure changes due to different serum level heights by using tonopen in acquired globes from the Iran Eye Bank

To investigate intraocular pressure [IOP] changes due to different serum level heights by using Tonopen in acquired globes from the Iran Eye Bank [IEB]. In this interventional prospective case series, serum were infused into 18 normal globes acquired from IEB by using 21G needle inserted in vitreal space through optic nerve head to change the IOP by different fluid level heights from the globe surface. IOP of globes were measured and recorded by Tonopen over the sclera and over the cornea at different serum level heights. Twelve globes were acquired from male donors and 6 globes were from female donors. Mean age of donors were 57 year old. Mean measured pressures by Tonopen of the 18 globes at the serum level heights of 13.6, 27.2, 40.8, 54.4 and 68 cm from the globe surface were 14, 23.6, 34.8, 44 and 52.8 mmHg over the sclera and 13.1, 22.8, 34.8, 44.1 and 52.8 mmHg over the cornea respectively. Using a Tonopen is a proper method to measure the acquired globes IOP, except in serum level height of 13.6 cm [10 mmHg] from the globe surface. In addition, if tonometry over the cornea is not available, it can be done by using Tonopen over the sclera