BACKGROUND: An irregular corneal surface compromises IOP measurement by Goldmann applanation tonometry. In such cases accurate measurement without corneal contact would be desirable. The new eyelid tonometer TGDc-01 measures IOP without corneal contact through the eyelid. The aim of the study was to evaluate the accuracy of the eyelid tonometer compared with Goldmann applanation tonometry (cornea thickness-corrected values) in subjects without corneal alterations. METHODS:IOP was measured in 199 eyes of 103 subjects without corneal alterations by means of two different methods. Measurements with the transpalpebral tonometer TGDc-01 and the Goldmann applanation tonometer were performed within 5 min in random order. RESULTS: The mean difference between lid tonometry and Goldmann applanation tonometry was 0.71 mmHg, SD +/-2.467 mmHg. In the reliability analysis the intraclass correlation coefficient was 0.8620. Compared with Goldmann applanation tonometry 66.4% of the IOP readings measured by lid tonometry were in an interval of +/-2 mmHg, 81.0% in an interval of +/-3 mmHg. The maximum of deviation was -6 mmHg and +6 mmHg, respectively. The Bland and Altman plots are shown. CONCLUSIONS:Lid tonometry correlates sufficiently with Goldmann applanation tonometry, but in more than 10% of the measurements the IOP readings differed by more than 3 mmHg. The eyelid tonometer may be helpful as a screening tool when Goldmann applanation tonometry is not applicable.
RCT Entities:
BACKGROUND: An irregular corneal surface compromises IOP measurement by Goldmann applanation tonometry. In such cases accurate measurement without corneal contact would be desirable. The new eyelid tonometer TGDc-01 measures IOP without corneal contact through the eyelid. The aim of the study was to evaluate the accuracy of the eyelid tonometer compared with Goldmann applanation tonometry (cornea thickness-corrected values) in subjects without corneal alterations. METHODS: IOP was measured in 199 eyes of 103 subjects without corneal alterations by means of two different methods. Measurements with the transpalpebral tonometer TGDc-01 and the Goldmann applanation tonometer were performed within 5 min in random order. RESULTS: The mean difference between lid tonometry and Goldmann applanation tonometry was 0.71 mmHg, SD +/-2.467 mmHg. In the reliability analysis the intraclass correlation coefficient was 0.8620. Compared with Goldmann applanation tonometry 66.4% of the IOP readings measured by lid tonometry were in an interval of +/-2 mmHg, 81.0% in an interval of +/-3 mmHg. The maximum of deviation was -6 mmHg and +6 mmHg, respectively. The Bland and Altman plots are shown. CONCLUSIONS: Lid tonometry correlates sufficiently with Goldmann applanation tonometry, but in more than 10% of the measurements the IOP readings differed by more than 3 mmHg. The eyelid tonometer may be helpful as a screening tool when Goldmann applanation tonometry is not applicable.
Authors: Jennifer Swingle Fogt; Cherie B Nau; Muriel Schornack; Ellen Shorter; Amy Nau; Jennifer S Harthan Journal: Optom Vis Sci Date: 2020-09 Impact factor: 2.106