Related Experiment Videos
[Disparity between applanation and impression tonometry in corneal edema]
Klinische Monatsblatter Fur Augenheilkunde
|November 1, 1982
Summary
Applanation tonometers underestimate intraocular pressure in edematous corneas compared to the Schiötz instrument. This difference, crucial for patients with glaucoma and poor retinal vascular function, stems from corneal alterations.
Area of Science:
- Ophthalmology
- Biomedical Engineering
Background:
- Acute glaucoma can cause corneal edema, potentially affecting intraocular pressure (IOP) measurements.
- Accurate IOP measurement is critical for managing glaucoma and preventing vision loss.
Purpose of the Study:
- To investigate the discrepancy in IOP readings between applanation and Schiötz tonometers in the presence of corneal edema.
- To identify the physical basis for the observed differences in tonometry values.
Main Methods:
- Experiments were conducted using rabbit corneae with induced edema.
- Characteristic alterations in edematous corneal tissue were analyzed.
- Tonometer specifications were considered in relation to corneal properties.
Main Results:
- Applanation tonometry yielded significantly lower IOP values than the Schiötz instrument in edematous corneas.
- Specific physical alterations in the edematous cornea were identified as the cause of this disparity.
Conclusions:
- Corneal edema significantly impacts IOP measurements, leading to underestimation by applanation tonometers.
- The findings have clinical implications for managing patients with coexisting acute glaucoma, corneal edema, and compromised retinal vascular function.