[Are we measuring the right intraocular pressure after excimer laser photorefractive laser keratoplasty in myopia?].
BACKGROUND
It is possible that the traditional method to determine the intraocular pressure after excimer-laser PRK is inaccurate. Measuring the pressure in the temporal part of the cornea might give the true values.


METHODS
Intraocular pressure was measured with a Goldmann Applanation Tonometer and with the Tonopen, before and after PRK for myopia in the central and in the temporal parts of the cornea. The paired student t-test was used for statistical analysis.


RESULTS
The results of central and temporal measurements before treatment were identical with both instruments. After PRK, central values were 2 to 3 mm Hg lower than temporal values when measured with a Goldmann Tonometer, and about 2 mm lower when measured with the Tonopen. The differences were highly significant (p < 0.0001 and p = 0.004 respectively).


CONCLUSIONS
The intraocular pressure measured in the usual manner after excimer-laser PRK is lower than the temporally measured pressure. These differences could be caused by absence of the Bowman's membrane, thinning of the cornea and/or change of its topography.
Schipper
I
I
Augenklinik Kantonsspital Luzern.
Senn
P
P
Niesen
U
U
D003315:Cornea / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D053685:Laser Therapy; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000503:physiopathology*; D012016:Reference Values; D012029:Refraction, Ocular; D014065:Tonometry, Ocular / Q000706:statistics & numerical data