Influence Of Postural Change On Intraocular Pressure Of Normal And Glaucomatous Eyes

Objective:To compare postural intraocular pressure(IOP)change in normal and primary open-angle glaucoma(POAG)eyes.Methods:Thirty normal volunteers(60eyes)(NC group)and twenty POAG patients(40eyes)(POAG group)were selected.Utilized Perkins applanation tonometry measure IOP at all positions. All patients were ordered to change the body posture from sitting(initial sitting)to recumbent then to sitting position again(post sitting).At the recumbent position IOP value measured for 25 minutes.The post sitting position recorded IOP values for 15 minutes.Results:In NC group,the average of initial sitting IOP value was 14.267±2.15mmHg,the supine position IOP was more than initial sitting position IOP,the different IOP value was 2.46±1.44mmHg.And the different IOP value of post to initial sitting IOP was -0.62±0.89mmHg.In POAG group,the average of initial sitting IOP value was28.15±5.37mmHg,the different IOP value of supine to initial sitting IOP was 4.85±1.94 mmHg,and was -2.025±1.79mmHg of post to initial sitting IOP.On the same position every point average of the IOP value approximately the same,between each other there was no obvious significant differences(p>0.05),but between different positions there was significant differences(P<0.05).When body posture changed,the IOP finished fluctuation in the first minute,didn't change much along with the time later.The range of average different value of IOP between different position in POAG group was significant difference to NC group(P<0.01).The normal and glaucoma eyes linear regression of the supine IOP with initial the sitting IOP presented positive correlation,r= 0.797 and r=0.946 separately(P< 0.01).And initial sitting position IOP with post sitting IOP also presented positive correlation r= 0.921and r=0.952 separately(P<0.01).Conclution:1.The supine IOP is higher than initial sitting IOP in both normal and POAG group.The post sitting IOP was less than the initial sitting IOP,especially in POAG group.When posture changes,the IOP finishes fluctuation in the first minute,doesn't change much along with the time.2.The range of different IOP value of different position in primary open-angle glaucoma group is more than healthy group.