Potential of vacuum-compression test in evaluation of corneal topographic indices for glaucoma diagnosis in young adults

PURPOSE. To evaluate the effectiveness of a novel loading corneal topographic test as a method for objectively determining intraocular pressure levels in the comprehensive diagnostics of glaucoma in young patients with corneal ectasia. METHODS. Fifteen patients with glaucoma and suspected glaucoma were examined at the Vostok-Prozrenie Eye Center. The average age was 33.9±8.02 years. All patients underwent standard ophthalmological examination and additional methods, including a vacuum-compression test (VCT) with corneal topographic indices recording before and during a short-term induced increase in IOP. RESULTS. In patients with glaucoma combined with corneal ectasia, the vacuum-compression load with induced IOP elevation revealed biomechanical and topographic changes: decreased corneal hysteresis, decreased IOP values, increased central corneal thickness and curvature, elevated anterior and posterior corneal surface elevation indices. CONCLUSION. In patients with low corneal hysteresis or fluctuating IOP levels, all patients should undergo corneal topography to detect corneal ectasia, which may lead to underestimation of tonometry results. A stress test with recording of corneal topography during induced IOP elevation can facilitate early detection of glaucoma combined with corneal ectasia in young patients.