Comparison of Noncontact tonometer with Goldmann Applanation tonometer for intraocular pressure measurement in non–glaucomatous patients in central India

Dr. Pande Arundhati S; Dr. Godbole Veerendra V; Dr. Halikar Swapnagandha S; Dr. Dudhbhate Anil D

Volume : IV, Issue : IV, April - 2014

Comparison of Noncontact tonometer with Goldmann Applanation tonometer for intraocular pressure measurement in non–glaucomatous patients in central India

Dr. Pande Arundhati S, Dr. Godbole Veerendra V, Dr. Halikar Swapnagandha S, Dr. Dudhbhate Anil D

Abstract :

The intraoccular pressure (IOP) value is a vital parameter in the detection of Glaucoma. The Goldmann Applanation tonometer (GAT) has been the “gold standard” for IOP measurements despite its inherent shortcomings. The IOP measurement by GAT requires topical anesthesia and direct corneal contact. The use of GAT can cause corneal aasion and carries risk of spread of infection. The process requires expertize and is time consuming. The Non contact tonometer (NCT) is an alternate tool for IOP measurement. It uses rapid air puff for IOP measurement. It does not require anesthesia or corneal contact and can be operated with relative ease as compared with GAT. The NCT is portable instrument, carries no risk of infection, especially well suited in post refractive surgery patients. Several studies available on comparison of NCT with GAT established that IOP measurements by NCT are comparable to IOP measurements by GAT, while there are still good number of studies reporting no statistical co-relation between IOP measurements by NCT and GAT.

Aims:

To compare NCT with GAT for IOP measurements in non-glaucomatous patients in central India.

Settings and Design:

Simple random study

Methods and Material:

The IOP measurements of 597 eyes in 300 non-glaucomatous patients were taken using both NCT and GAT tools in central India. The IOP was first measured by NCT and then by GAT in same patient after a gap of 10 minutes.

Statistical analysis used:

Student’s t-test & the Bland Altman methods. The analysis was carried using Microsoft Excel.

Results:

Mean IOP reading by NCT is 14.73mm of Hg with a standard deviation of 2.68 whereas the Mean IOP reading by GAT is 12.61mm of Hg with a standard deviation of 2.65. The difference in readings is statistically significant p = 0.0001.

Conclusions: Mean difference of IOP was statistically significant in NCT and GAT. So NCT should not be used as diagnostic tool for IOP measurement. However NCT can be used as a screening tool in community practice