Eye & Contact Lens

Skip Navigation LinksHome > September 2012 - Volume 38 - Issue 5 > Tonopen XL Assessment of Intraocular Pressure Through Silico...
Eye & Contact Lens: Science & Clinical Practice:
doi: 10.1097/ICL.0b013e318257a123

Tonopen XL Assessment of Intraocular Pressure Through Silicone Hydrogel Contact Lenses

Schornack, Muriel O.D.; Rice, Melissa O.D.; Hodge, David M.S.

Collapse Box


Objectives: To assess the accuracy of Tonopen XL measurement of intraocular pressure (IOP) through low-power (−0.25 to −3.00) and high power (−3.25 to −6.00) silicone hydrogel lenses of 3 different materials (galyfilcon A, senofilcon A, and lotrafilcon B).

Methods: Seventy-eight patients were recruited for participation in this study. All were habitual wearers of silicone hydrogel contact lenses, and none had been diagnosed with glaucoma, ocular hypertension, or anterior surface disease. IOP was measured with and without lenses in place in the right eye only. Patients were randomized to initial measurement either with or without the lens in place. A single examiner collected all data.

Results: No statistically significant differences were noted between IOP measured without lenses and IOP measured through low-power lotrafilcon B lenses or high-power or low-power galyfilcon A and senofilcon A lenses. However, we did find a statistically significant difference between IOP measured without lenses and IOP measured through high-power lotrafilcon B lenses.

Conclusion: In general, Tonopen XL measurement of IOP through silicone hydrogel lenses may be sufficiently accurate for clinical purposes. However, Tonopen XL may overestimate IOP if performed through a silicone hydrogel lens of relatively high modulus.

© 2012 Lippincott Williams & Wilkins, Inc.


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.