Purpose:
Compare the posture-induced changes in the intraocular pressure in glaucoma patients treated surgically and clinically as well as to compare the ocular perfusion pressure stability proportioned by these 2 modalities of glaucoma treatment.
Methods:
Patients were recruited from the GLAUCOMA section of UNIFESP. three groups were evaluated: (A) controlled glaucomatous patients that had undergone trabeculectomy surgery, in use of no medications; (B) Glaucomatous patients controlled with anti-glaucomatous drugs; (C) control group, patients without glaucoma. The patients were asked to remain seated for 10 minutes and then had their baseline IOP measured with the Tonopen tonometer. The patients then assumed the supine position and once again had their IOP measured with the same tonometer at 5 minutes intervals until the IOP got back to it’s baseline levels or reached stability. The IOP values were achieved by the median of at least three acceptable readings of the tono-pen (5%). The arterial pressure was also measured right after each IOP measurement, with sphygmomanometer and stethoscope, in order to calculate the ocular perfusion pressure. Wald Chi Square Test was used to compare the groups.
Results:
Eighteen eyes were evaluated in group 1,twenty four in group 2, eighteen in group 3. In group 1,comparing the IOP seated with the IOP in supine position there is a transient rise until the 10-minutes measurement, after which the difference is no longer statistically significant(p=0,19).In group 2 the difference is sustained until the last measurement(p=0,001). Group 3 showed a pattern similar to group 1, with the IOP rise loosing its statistical significance after 10 minutes of supine position(p=0,18).There was no statistical difference between groups when comparing the OPP in seated patients with the OPP in different times of supine position (p=0,19).
Conclusions:
This study suggests that trabeculectomy could provide stability in the IOP levels in glaucomatous eyes during the postural change from a sitting/upright position to the supine position. It also suggests that the IOP control might not be satisfactory during supine position in patients controlled with anti-glaucomatous drugs.
Keywords: intraocular pressure • differentiation