Dynamic contour tonometry in asymmetric glaucoma patients

Emilio Rintaro Suzuki Jr1, Cibele Lima Belico Suzuki1, Danielle Carlier1, Daniele Penha1, Marta dos Anjos Rodrigues Parchen¹, Wagner Duarte Batista¹, Joao Agostini Netto^2
1Glaucoma Service, 2Department of Ophthalmology, Santa Casa de Belo Horizonte, MG, Brazil

Background: The purpose of this study was to determine any difference in dynamic contour tonometry and ocular pulse amplitude in asymmetric glaucoma patients with the same applanation intraocular pressure.
Methods: This is a prospective, observational study of 30 glaucoma patients and 11 controls from June 2007 to February 2008. Most of the glaucoma patients were on prostaglandin analog treatment.
Results: Mean applanation intraocular pressure in the control group was 14.28 mmHg for the right eye and 14.10 mmHg for the left eye (P > 0.05). Corneal thickness was 519.10 µm for the right eye and 511.07 µm for the left eye (P > 0.05). Mean dynamic contour tonometry intraocular pressure was 17.28 mmHg for the right eye and 17.25 mmHg for the left eye (P > 0.05). Mean ocular pulse amplitude was 2.80 mmHg for the right eye and 2.92 mmHg for the left eye (P > 0.05).
Conclusion: No differences in ocular pulse amplitude were found between the two groups and between the worst and the best eye. In spite of there being no difference in ocular pulse amplitude, dynamic contour tonometry intraocular pressure was 2.44 mmHg higher in the worst eye than in the best eye in the glaucoma patients, even with the same applanation intraocular pressure. Further studies are needed to confirm if this difference is related to glaucoma progression or a worst prognosis and whether it can be considered to be a new risk factor.

Keywords: dynamic contour tonometry, central cornea thickness, assymetric glaucoma