ProTon tonometer determination of intraocular pressure in patients with scarred corneas.
OBJECTIVE
To evaluate the measure of intraocular pressure (IOP) in patients with scarred corneas obtained from the affected and non-affected areas.


METHODS
Eighteen patients with small maculo-leucomatous corneal opacity following microbial keratitis were prospectively included in the study. Goldmann applanation tonometry was done first on the non-affected corneal surface. ProTon tonometry (PT) was then carried out on the same eye, to obtain IOP measurements from the non-affected (PT1) and the affected area (PT2) of the cornea. The IOP measurements were compared using a two-tail paired t test.


RESULTS
The mean of IOP measurements of PT 2 and PT1 was 22 mm of Hg (SD +/- 5.2) and 14.8 mm of Hg (SD +/- 5.4), respectively. The higher reading of PT2 was statistically significant ( P < 0.001). The mean Goldmann applanation tonometry was 14.6 mm of Hg (SD 5.4) and it did not differ significantly ( P = 0.86) from the PT1 readings of 14.8 mm of Hg (SD 5.4).


CONCLUSIONS
In patients with maculo-leucomatous corneal opacity, determination of IOP by ProTon tonometer varies from the affected to the non-affected area. The ProTon tonometer overestimates the level of IOP when it is applied to a leucomatous corneal opacity.
Jain
Arun K
AK
Department of Ophthalmology, Post Graduate Institute of Medical Research and Education, Chandigarh, India. aronkjain@yahoo.com
Sukhija
Jaspreet
J
Gupta
Amod
A
D000293:Adolescent; D000328:Adult; D002648:Child; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology*; D003315:Cornea / Q000473:pathology*; D003318:Corneal Opacity / Q000473:pathology / Q000503:physiopathology*; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D014065:Tonometry, Ocular / Q000295:instrumentation*