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The Icare-Pro Rebound Tonometer Versus the Hand-held Applanation Tonometer in Congenital Glaucoma
Lara Borrego Sanz1, Laura Morales-Fernandez, Jose M Martínez de-la-Casa
1Clínico San Carlos Hospital, Madrid, Spain.
Insights
The Icare-Pro rebound tonometer provides reliable intraocular pressure (IOP) measurements in children with primary congenital glaucoma (PCG) under anesthesia, correlating well with the established Perkins tonometer.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Glaucoma Research
Background:
- Accurate intraocular pressure (IOP) measurement is crucial for managing pediatric glaucoma.
- Primary congenital glaucoma (PCG) often requires general anesthesia for tonometry.
- The Icare-Pro rebound tonometer is a newer device for IOP assessment.
Purpose of the Study:
- To compare IOP measurements between the Icare-Pro rebound tonometer and the Perkins hand-held applanation tonometer.
- To evaluate the reliability of the Icare-Pro in children with PCG under general anesthesia.
Main Methods:
- Prospective study involving 50 eyes of 50 patients with PCG under general anesthesia.
- Three IOP measurements were taken with both Icare-Pro (first) and Perkins tonometers.
- Central corneal thickness, anterior chamber depth, and axial length were also measured.
- Data analyzed using interclass correlation coefficient and Bland-Altman plots.
Main Results:
- Good linear correlation (r=0.75) and agreement (ICC=0.74) were found between Icare-Pro and Perkins IOP readings.
- Icare-Pro readings were slightly higher (mean difference 0.42 ± 3.69 mm Hg).
- No correlation of IOP with central corneal thickness or axial length; positive relation with anterior chamber depth.
Conclusions:
- The Icare-Pro rebound tonometer demonstrates good correlation and agreement with the Perkins tonometer for IOP measurement in children with PCG under general anesthesia.
- This suggests the Icare-Pro is a viable option for IOP assessment in this population.
Purpose:
To compare intraocular pressure (IOP) measurements obtained using the new rebound tonometer Icare-Pro and the hand-held version of Goldmann Applanation Tonometer (Perkins tonometer) in children with primary congenital glaucoma (PCG) under general anesthesia.
Materials And Methods:
Using both tonometers, 3 IOP measurements were prospectively determined in 1 single session. Icare-Pro was always used first, and then Perkins. All measurements were recruited in 50 eyes of 50 patients with PCG under general anesthesia. Central corneal thickness, anterior chamber depth, and axial length were also measured in each patient. Data were compared by determining interclass correlation coefficient for each tonometer and representing the differences detected as Bland-Altman plots.
Results:
Good linear correlation was observed between IOP readings obtained using the Perkins and Icare-Pro (r=0.75, P<0.001), although the Icare-Pro readings were slightly higher (mean IOP difference 0.42 ± 3.69 mm Hg, P=0.41). A Bland-Altman plot revealed the 95% limits of agreement between the 2 methods: 7.7 to -6.8 mm Hg (slope=0.109, P=0.32). Intraclass correlation coefficient was 0.74 (95% confidence interval, 0.59-0.84) showing good agreement. For both tonometers, no correlation was detected between IOP measurements and central corneal thickness and axial length, but positive relation was found with anterior chamber depth.
Conclusions:
IOP measurements determined using the new Icare-Pro rebound tonometer showed good correlation with those obtained using the hand-held Perkins applanation tonometer in children with PCG under general anesthesia.
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