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COMPARISON OF IOP READINGS USING REBOUND I CARE TONOMETER AND PERKINS APPLANATION TONOMETER IN AN AFRICAN POPULATION
D S Ademola-Popoola1, A F Odi, T M Akande
1Department of Ophthalmology, University of Ilorin Teaching Hospital, Ilorin, Nigeria.
Insights
The ICare tonometer provides accurate intraocular pressure (IOP) readings comparable to the Perkins tonometer. ICare is significantly easier to use in young children without sedation, making it a valuable tool for pediatric glaucoma management.
Area of Science:
- Ophthalmology
- Medical Devices
- Pediatric Care
Background:
- Intraocular pressure (IOP) monitoring is crucial for glaucoma diagnosis and management.
- Pediatric IOP measurement presents unique clinical challenges.
- Handheld tonometers like ICare (rebound method) and Perkins (applanation) are commonly used.
Purpose of the Study:
- To compare IOP values obtained from ICare and Perkins tonometers.
- To assess the ease of use of both tonometers in young children.
- To document successful IOP measurement positions in pediatric patients.
Main Methods:
- IOP readings were taken by experienced examiners without sedation or anesthesia.
- ICare tonometer was used first, followed by Perkins.
- Paired sample T-test was employed for statistical analysis of mean IOP differences.
Main Results:
- A high correlation and no statistically significant difference in mean IOP between ICare and Perkins tonometers.
- The mean difference in IOP readings was within 2mmHg for 66.2% of eyes.
- ICare demonstrated a significantly higher success rate (97.6%) compared to Perkins (50%) in children aged ≤6 years.
Conclusions:
- ICare tonometer readings are comparable to Perkins tonometer readings.
- ICare offers superior ease of use in young children (≤6 years) without requiring sedation or anesthesia.
- ICare is a practical and effective tool for IOP measurement in pediatric populations, particularly in African settings.
Background:
Accurate intra ocular pressure (IOP) measurement and monitoring using tonometry is a common clinical measurement in diagnosis and management of glaucoma, this is often a challenge in children. The ICare and Perkins tonometers are both handheld tonometers, Perkins uses applanation while ICare measures IOP with a rebound method.
Objectives:
The objectives of research were to study the IOP values from each tonometer, compare the value of IOP readings from both tonometers, determined the ease of their use in young children and document the various positions in which the tonometers were used successfully in children.
Method:
Intra ocular pressure readings were taken by two experienced examiners in upright position without sedation or anaesthesia. ICare tonometer was first used. Data were entered and analysed with SPSS 17 statistical package. The means were compared using paired sample T-test.
Results:
A total of 480 eyes of 240 persons, aged between 2months and 90years with a mean of 46.2±22 years had their intra-ocular pressure range between 3 and 44mmHg( Mean16.3±6) measured using ICare and Perkins tonometry. There was a high correlation, and no statistically significant differences in the mean IOP comparing ICare and Perkins tonometers. The mean difference in average IOP readings between ICare and Perkins was -0.08±2.8 (95% CI: 0.45-0.30; r=0.87, p= 0.68) for right eye and -0.15±2.8mmHg (95% CI -0.53 to 0.23; r=0.86, p=0.44) in the left eye The difference in the average IOP reading from both tonometers was within 2mmHg 288(66.2%) eyes. Among the 147 (33.8%) eyes with a difference in IOP greater than 2mmHg, Perkins was responsible for the higher IOP reading in 76(51.7%) and ICare in 71(48.3%) p=0.56. Among 42 eyes of 21 children aged ≤6years, IOP reading was successfully taken in 41(97.6%) and 21(50%) eyes with ICare and Perkins respectively without sedation or anaesthesia.
Conclusion:
The IOP readings using the ICare tonometer compares well with that of Perkins tonometer. The ICare was easier to use in young children (≤6year olds) without sedation or anaesthesia in this African population.
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