Estudo comparativo entre o tonômetro de aplanação de Goldmann e o tonômetro de contorno dinâmico de Pascal no glaucoma primário de ângulo aberto e olhos normais Dynamic contour tonometry (DCT) versus Goldmann applanation tonometry (GAT) in open-angle glaucoma and normal eyes: a comparative study

Abstract

OBJETIVO: Comparar as medidas da pressão intra-ocular (PIO) obtidas com o tonômetro de aplanação de Goldmann (TAG) e o tonômetro de contorno dinâmico (TCD) e correlacioná-las com a espessura central da córnea (ECC). MÉTODOS: Estudo transversal, com os pacientes divididos em dois grupos: glaucoma primário de ângulo aberto (GPAA) e olhos normais (ON). As medidas da PIO foram obtidas em todos os pacientes com o TAG e o TCD. Um examinador realizou as tonometrias com o TAG e outro examinador com o TCD. A ECC foi obtida pelo paquímetro ultrassônico. Os resultados foram avaliados através do teste Z para amostras independentes, teste t de Student para amostras relacionadas, teste de correlação linear de Pearson e gráfico de Bland-Altman. RESULTADOS: Foram incluídos 134 olhos de 71 pacientes. O grupo GPAA foi constituído por 85 olhos de 45 pacientes e o grupo ON por 49 olhos de 26 indivíduos com olhos normais. Não houve diferença significativa da ECC entre os dois grupos em ambos os olhos (p= 0,54 OD; p= 0,71 OE). As tonometrias realizadas com o TCD foram maiores nos dois grupos (GPAA: pPURPOSE: To compare intraocular pressure (IOP) readings of Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT), and to correlate central corneal thickness (CCT) with these readings. METHODS: This transversal study included patients in two groups: open-angle glaucoma (OAG) and normal eyes (NE). IOP measurements were obtained in all patients using GAT and DCT. The same examiner made all GAT measurements. Another examiner, who was masked to the GAT readings, made DCT measurements. CCT was determined by ultrasound pachimetry. RESULTS: The study included 134 eyes of 71 subjects. The groups were composed of 85 eyes from 45 patients with OAG and 49 eyes from 26 subjects with NE. There was no statically significant difference between CCT in the two groups (p = 0,54, right eye; p = 0,71, left eye). DCT readings consistently were higher than GAT measurements in the two groups (OAG: p < 0,001; NE: p = 0,01). There was good correlation between GAT and DCT in both groups (p < 0,001). Neither GAT nor DCT showed a significant correlation with CCT, except in the separate analysis of all right eyes (p = 0,03; r² = 0,07). Bland-Altman graphs showed disagreement between GAT and DCT. CONCLUSION: Measurements with both GAT and DCT were not correlated with CCT. The agreement between GAT and DCT were not good. The IOP measurements by GAT were lower when compared with DCT. DCT readings seem to be less dependent on CCT than TAG readings.

Keywords

• Glaucoma de ângulo aberto
• Pressão intra-ocular
• Técnicas de diagnóstico oftalmológico
• Tonometria ocular
• Estudos de casos e controles
• Glaucoma, open-angle
• Intraocular pressure
• Diagnostic techniques, ophthalmological
• Tonometry, ocular
• Case-control studies