Abstract
Purpose :
To compare peak diurnal intraocular pressure (IOP) assessed by serial home tonometry using the iCare HOME tonometer by the water drinking test (WDT).
Methods :
Healthy adults 20-40yrs old with normal ocular health were eligible for inclusion. One eye selected at random was enrolled in the study. All study IOP measurements are the mean of 3 sequential recordings of “Excellent” or “Good” reliability obtained via self-tonometry using an iCare HOME device in an upright seated posture. The WDT was performed after a training session and demonstrated proficiency using the tonometer. Baseline IOP was established, then 1 liter of bottled drinking water was consumed within 5 min. Self-tonometry was performed at 15, 30 and 45 min. The tonometer was then dispensed to the patient for serial home tonometry performed every 2 hrs over a 24 hr period commencing >12 hrs following the WDT. Finally, the subject completed an opinion survey regarding the two procedures.
Results :
11 subjects (5M, 6F; 5 OD, 6 OS; mean±SD age: 24.6±1.8yr) completed the study. Peak IOP achieved during the WDT was significantly correlated with the peak obtain by serial home tonometry (r = 0.81, p = 0.003). Mean (±SD) difference in peak IOP between the two procedures was 0.2±2.2 mmHg, with ±4.3 mmHg 95% CI. Reliability of home tonometry assessed via agreement of the 3 sequential IOP measurements was excellent (ICC(2,1): 0.86; 95%CI: 0.58-0.94). There was no indication that nocturnal measurements (00:00-06:00 hours) were less reliable than those obtained during waking hours (NIGHT ICC(2,1): 0.87; 95%CI: 0.57-0.95, DAY ICC(2,1): 0.86; 95%CI: 0.57-0.94). Survey responses indicated that a majority of subjects (73%-82%) had no difficulty performing either procedure; however, a majority expressed preference for the WDT (64% vs 36%).
Conclusions :
There is good agreement between serial home tonometry performed using the iCare HOME tonometer and the WDT in estimating peak diurnal IOP of healthy young adults. These results suggest that both procedures may be useful in the assessment of peak diurnal IOP. Further research in glaucoma patients is warranted.
This is a 2021 ARVO Annual Meeting abstract.