Abstract
Purpose :
To evaluate the feasibility and accuracy of using the Terahertz (THz) scanning system as a quantitative tool in the evaluation of corneal edema.
Methods :
Fifty fresh porcine corneas and ten human cadaveric corneas with different extents of corneal edema resulting from different time duration after procurement were used. All the corneas were scanned with the TPS Spectra 3000 Teraview Terahertz scanning system, as well as the anterior segment optical coherence tomography systems for the central corneal thickness (CCT). The porcine corneas were further scanned for 5 consecutive days. The THz peak intensity and the area under the curve (AUC) from the spectral domain was recorded, and were correlated with the CCT measurements.
Results :
For the 50 porcine eyes, the THz peak intensity and AUC, as well as the CCT, increased with time (Figure 1). The mean peak signal intensity was 159951±5122, 177338±5012, 224761±6223, 250290±5665, and 327236±6368 atomic units, mean AUC was 72978±4689, 77368±6522, 80913±5651, 80914±7815, and 153146±6790, and mean CCT was 682±45, 745±68, 836±48, 1006±66, and 1225±62 μm, for the corneas with the procurement time of 0, 1, 2, 3 and 4 days, respectively. The correlation was stronger between the AUC and CCT (r=0.80, P=0.028), than between the peak intensity and CCT (r=0.75, P=0.034). For the human cadaveric corneas with different extents of corneal edema, the AUC was positively and strongly correlated with the CCT (r=0.81, P=0.014).
Conclusions :
The Terahertz scanning system has the potential to be used a novel tool to quantitatively evaluate corneal edema. It may be helpful in monitoring the disease progression in patients with corneal edema.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.