1.Five-year, private sector cost comparison of iStent inject®w, trabeculectomy, glaucoma medications for primary open-angle glaucoma with and without phacoemulsification: A filipino patient perspective.
Jose Ma Martinez ; Rommel Bautista ; Ivan Tecson ; Alice Chu ; Sheena Suthen ; David Champion ; Anand Jha
Philippine Journal of Ophthalmology 2026;51(1):7-16
OBJECTIVE
To perform a cost comparison of the 5-year total direct medical costs of iStent inject® W vs. trabeculectomy vs. glaucoma medications for the treatment of primary open-angle glaucoma, with and without phacoemulsification, from the perspective of Filipino patients.
METHODSThis cost-comparative analysis compared total private sector costs of surgery, post-operative care, and medication usage over 5 years on combined phacoemulsification (combined) or standalone (SA) procedures using iStent inject W, trabeculectomy, and glaucoma medications for the general population and senior citizens/individuals with disabilities. Data, including unit costs and frequencies, were obtained from published literature and local primary research. Scenario analysis consisted of three payment models: 100% out-of-pocket (OOP), coverage from PhilHealth public health insurance, and combined subsidies from both private and PhilHealth insurance.
RESULTSiStent inject W was less costly than glaucoma medications in all scenarios and patient populations. When compared with trabeculectomy, iStent inject W, was less costly in all patient populations in the OOP scenario, providing savings of 5% for SA procedures and 5% to 6% for combined procedures. It was also less costly as a combined procedure in all populations in the combined private health and PhilHealth insurance scenario, offering 6% savings in the general population and 9% in elderly and disabled patients. However, it was costlier by 1% in the PhilHealth scenario. As an SA procedure, it was costlier vs. trabeculectomy in both populations in the PhilHealth and PhilHealth plus private health insurance scenarios by 18% to 22% and 101% to 109%, respectively. The highest incremental cost for iStent inject W was US$1,662 vs. trabeculectomy as an SA procedure in the general population under the combined private health and PhilHealth insurance scenario.
CONCLUSIONFor Filipino glaucoma patients who are treated in the private sector, iStent inject W, whether combined or as an SA procedure, may be cost-saving compared with glaucoma medications over a 5-year period; however, it may be costlier compared with trabeculectomy depending on health insurance coverage scenarios.
Human ; Glaucoma ; Philippines ; Costs And Cost Analysis
2.Comparative analysis of cataract refractive outcomes based on varied axial length and keratometry measurements from diverse diagnostic devices
Robert Edward T. Ang ; Ivan O&rsquo ; neill C. Tecson ; Bennice Leslie Hope F. Robles ; Ryan S. Torres ; Maria Fe S. Navarrete ; Emerson M. Cruz
Philippine Journal of Ophthalmology 2025;50(1):10-17
OBJECTIVE
To compare the refractive absolute error when axial length (AL), anterior chamber depth (ACD) and keratometry (K) are sourced from different measuring devices (IOL Master vs a combination of automated keratometer and A-scan) and inputted into the Barrett Universal II or SRK/T formula.
METHODSThis was a retrospective study. Medical charts of eyes that underwent uncomplicated phacoemulsification with in-the-bag implantation of Envista or multifocal FineVision IOL were reviewed. The results of manifest refraction at 1 month after surgery were collected. The predicted refraction corresponding to the IOL power implanted was collected from 4 IOL sheets: using the SRK/T with AL, ACD, and K from IOL Master (Group A); SRK/T formula with AL and ACD from A-scan and K from the automated keratometer (Group B); Barrett formula with AL, ACD and K from IOL Master (Group C); and Barrett formula using with AL, ACD from A-scan and K from automated keratometer. For each group, the absolute error, prediction error, and variances of prediction error were computed.
RESULTSA total of 132 eyes were included in the study: 56 in the monofocal group and 76 in the multifocal group. The means of manifest refraction spherical equivalent (MRSE) were 0.06 ± 0.38 D and –0.08 ± 0.31 D in the monofocal and multifocal groups, respectively. When AL and K were obtained from various sources and entered into the Barrett formula, the mean absolute error difference in both the monofocal (p = 0.70) and multifocal (p = 0.10) groups did not reach statistical significance. If the SRK/T formula was used, similar outcomes were observed (monofocal p = 0.97; multifocal p = 0.37). When compared to A-scan groups, the prediction error variances are significantly smaller in the groups that used the IOL Master as their data source. Among the four groups, the Barrett group using IOL Master as the data source showed the lowest overall variation of prediction error (monofocal F = 0.04; multifocal F = 0.03).
CONCLUSIONThough the refractive outcomes may not be statistically different, using the IOL Master as the source of AL and K makes the refractive outcomes more consistent and predictable. Combining the AL and K from the IOL Master with the Barrett Universal II formula further increases the predictability of refractive outcomes.
Human ; Anterior Chamber ; Cataract

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