Correlation Between Intraocular Pressure Measurements Using Applanation Tonometry and Ocular Response Analyzer (Ora) in Primary Congenital Glaucoma (Pcg) Patients

Objective: This study aims to assess the degree of agreement between IOP measured usingPerkins and Goldmann applanation tonometers, and both Goldmann correlated intraocular pressure(IOPg) and corneal compensated intraocular pressure (IOPcc) measured using ORA in PCG patients.Study Design: a prospective, single-center, observational study. Patients and Methods: Allpatients with PCG and fulfilling the inclusion criteria of the study underwent full ophthalmologicalexamination and CCT measurement using ultrasound pachymetry. Applanation tonometer was usedto measure the IOP. ORA was used to detect CH, CRF, IOPcc, and IOPg. Agreement between IOPmeasured using applanation tonometers, and both IOPg and IOPcc was tested using interclasscorrelation (ICC). Results: Forty three eyes of 28 patients were included. Twenty two were males.The mean patients age was 9.14 years. The mean IOP measured using applanation tonometry was16.07 mmHg. The mean IOPg was 21.857 mmHg. The mean IOPcc was 24.17 mmHg. The meandifference of IOP measured by applanation and both IOPg and IOPcc was 5.78 mmHg and8.1mmHg respectively with higher measurements by ORA. These differences were statisticallysignificant (p =0.00). IOPg error % was statistically significantly positively correlated with CCT(p=0.009) and CRF (p=0.00) with correlation coefficient of 0.399 and 0.504 respectively. IOPccerror % was statistically significantly negatively correlated with CH (p=0.034) with correlation coefficient of - 0.324. Conclusion: In the current study, a statistically significant difference betweenthe IOP measured using applanation tonometry and ORA obtained IOP namely IOPg and IOPccwas detected with higher ORA measurements.