Effect of Manual Upper Eyelid Elevation on Intraocular Pressure Measurement by Four Different Tonometers

Effect of manual upper eyelid elevation on intraocular pressure measurement by noncontact tonometer

PURPOSE

To evaluate whether manual upper eyelid elevation (MUEE) affects intraocular pressure (IOP) values obtained with a noncontact tonometer (NT).

METHODS

This cross-sectional study included 122 eyes of 122 non-glaucomatous adults. All patients underwent IOP measurement using both NT and Goldmann applanation tonometer (GAT). The order of measurements was NT without MUEE, NT with MUEE, and GAT. Both eyes of each patient were measured and one of the eyes was randomly selected for inclusion in the study. Central corneal thickness (CCT) and palpebral fissure height (PFH; distance between upper and lower eyelids) was recorded.

RESULTS

The patients' mean age was 43.91 ± 12.36 (20-61) years and 62.3% were women. Mean IOP values measured by NT without MUEE, NT with MUEE, and GAT were 15.98 ± 2.39, 15.84 ± 2.53, and 14.33 ± 2.3 mmHg, respectively. There was no statistically significant difference in mean IOP between NT without and with MUEE (p = 0.506). Mean IOP values obtained by NT with and without MUEE were significantly higher than those obtained by GAT (p < 0.001). The difference in IOP values measured by NT without and with MUEE was positively correlated with PFH (r = 0.214; p = 0.018). CCT and IOP values obtained by NT without MUEE and GAT were positively correlated (r = 0.300; p = 0.001 and r = 0.311; p = 0.001, respectively).

CONCLUSION

MUEE does not have a significant effect on IOP measurements by NT. The difference between IOP measured by NT without and with MUEE increases with greater PFH.

Evaluation of rebound tonometer iCare IC200 as compared with IcarePRO and Goldmann applanation tonometer in patients with glaucoma

Background

This study investigated the agreement between a new rebound tonometer, IC200, and IcarePRO and Goldmann applanation tonometry (GAT).

Methods

This was a prospective cross-sectional study. We measured the intraocular pressure (IOP) in 145 eyes of 145 glaucoma patients in the sitting position using GAT, IcarePRO, and IC200. IcarePRO and IC200 measurements were also obtained in the supine position. IC200 measurement was performed using two modes: single six (IC200-single) and automatic (IC200-continuous) six-measurements mode.

Results

All tonometers provided high reproducibility in both positions (all intraclass correlation coefficients > 0.90), although it was highest with GAT, followed by IC200-continuous and IC200-single and then IcarePRO. In the sitting position, the mean (± SD) IOPs of GAT, IcarePRO, IC200-single, and IC200-continuous were 14.5 ± 2.9 mmHg, 13.3 ± 3.2 mmHg, 11.6 ± 3.2 mmHg, and 11.5 ± 3.2 mmHg, respectively. IOPs measured with IcarePRO or IC200 were significantly lower than those with GAT, particularly in patients with low IOP. IOPs measured with all tonometers were significantly elevated in the supine position as compared with the sitting position, but this difference was significantly greater with IC200-single and IC200-continuous compared with IcarePRO. IOP elevation was significant in eyes without bleb versus those with bleb, but this finding was not observed when IOP was measured with IcarePRO. The IOPs of the single and continuous modes of IC200 were interchangeable in both positions.

Conclusions

GAT, IcarePRO, and IC200 had sufficiently high reproducibility, but measurements with IcarePRO may not be accurate in the supine position. Elevation of IOP in the supine position, especially in eyes with bleb, was more sensitively captured with IC200 than with IcarePRO.

Trial registration

Japan Clinical Trials Register, No. UMIN000039982.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-021-00249-z.

Comparative Evaluation of Rebound and Perkins Tonometers in Pediatric Glaucoma With Varied Corneal Characteristics

PRECIS

Icare tonometer overestimated intraocular pressure (IOP) as compared with Perkins and this variation was higher in IOP>19 mm Hg and corneal opacity in patients with pediatric glaucoma.

PURPOSE

To compare the IOP measured by Icare ic200 with Perkins tonometer in pediatric glaucoma with different corneal characteristics.

METHODS

Patients of pediatric glaucoma posted for routine examination under anesthesia, age below 12 years were enrolled. All patients underwent IOP measurement with Perkins and Icare ic200 tonometer by the same observer. Basic demographic data and other relevant clinical data were recorded. Central corneal thickness (CCT), horizontal corneal diameter, and corneal characteristics such as cornea clarity was recorded.

RESULTS

A total of 194 eyes of 105 patients were analyzed. The difference between Perkins and Icare IOP was -0.816 mm Hg with the Bland-Altman plot 95% limits of agreement (LoA) from -11.194 to 9.562 mm Hg and 5.1% (10) values lying outside LoA. At IOP <19 mm Hg, the difference was -0.65 mm Hg and IOP ≥19 mm Hg, the difference was higher, -1.12 mm Hg. In the clear cornea group (123 eyes), the difference in IOP by 2 tonometers was -0.776 mm Hg with the Bland-Altman plot 95% LoA between -10.679 and 9.128 mm Hg. In hazy corneas (36 eyes), the difference in IOP was 0.531 mm Hg. The Bland-Altman plot showed 95% LoA between -6.242 and 7.303 mm Hg. In the scarred cornea group (35 eyes), the difference in IOP between the 2 was -2.343 mm Hg and the Bland-Altman plot showed wide 95% LoA from -16.302 to 11.616 mm Hg.

CONCLUSION

Icare tonometer overestimated IOP as compared with Perkins and this variation was higher in eyes with IOP≥19 mm Hg, CCT >615 μm, and scarred corneas. A moderate correlation between IOP and CCT for both tonometers was noted.