Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines
The endothelial layer of the cornea plays a critical role in regulating its hydration by actively controlling fluid intake in the tissue via transporting the excess fluid out to the aqueous humor. A damaged corneal endothelial layer leads to perturbations in tissue hydration and edema, which can imp...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-11-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/22/23/9071 |
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| author | Andrew Chen Zachery B. Harris Arjun Virk Azin Abazari Kulandaiappan Varadaraj Robert Honkanen Mohammad Hassan Arbab |
| author_facet | Andrew Chen Zachery B. Harris Arjun Virk Azin Abazari Kulandaiappan Varadaraj Robert Honkanen Mohammad Hassan Arbab |
| author_sort | Andrew Chen |
| collection | DOAJ |
| description | The endothelial layer of the cornea plays a critical role in regulating its hydration by actively controlling fluid intake in the tissue via transporting the excess fluid out to the aqueous humor. A damaged corneal endothelial layer leads to perturbations in tissue hydration and edema, which can impact corneal transparency and visual acuity. We utilized a non-contact terahertz (THz) scanner designed for imaging spherical targets to discriminate between ex vivo corneal samples with intact and damaged endothelial layers. To create varying grades of corneal edema, the intraocular pressures of the whole porcine eye globe samples (<i>n</i> = 19) were increased to either 25, 35 or 45 mmHg for 4 h before returning to normal pressure levels at 15 mmHg for the remaining 4 h. Changes in tissue hydration were assessed by differences in spectral slopes between 0.4 and 0.8 THz. Our results indicate that the THz response of the corneal samples can vary according to the differences in the endothelial cell density, as determined by SEM imaging. We show that this spectroscopic difference is statistically significant and can be used to assess the intactness of the endothelial layer. These results demonstrate that THz can noninvasively assess the corneal endothelium and provide valuable complimentary information for the study and diagnosis of corneal diseases that perturb the tissue hydration. |
| first_indexed | 2024-03-09T17:33:10Z |
| format | Article |
| id | doaj.art-bbe85275f8bd4d4383a55a65e1ea802b |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-09T17:33:10Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-bbe85275f8bd4d4383a55a65e1ea802b2023-11-24T12:07:59ZengMDPI AGSensors1424-82202022-11-012223907110.3390/s22239071Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector MachinesAndrew Chen0Zachery B. Harris1Arjun Virk2Azin Abazari3Kulandaiappan Varadaraj4Robert Honkanen5Mohammad Hassan Arbab6Department of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Ophthalmology, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Physiology and Biophysics, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Ophthalmology, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USADepartment of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USAThe endothelial layer of the cornea plays a critical role in regulating its hydration by actively controlling fluid intake in the tissue via transporting the excess fluid out to the aqueous humor. A damaged corneal endothelial layer leads to perturbations in tissue hydration and edema, which can impact corneal transparency and visual acuity. We utilized a non-contact terahertz (THz) scanner designed for imaging spherical targets to discriminate between ex vivo corneal samples with intact and damaged endothelial layers. To create varying grades of corneal edema, the intraocular pressures of the whole porcine eye globe samples (<i>n</i> = 19) were increased to either 25, 35 or 45 mmHg for 4 h before returning to normal pressure levels at 15 mmHg for the remaining 4 h. Changes in tissue hydration were assessed by differences in spectral slopes between 0.4 and 0.8 THz. Our results indicate that the THz response of the corneal samples can vary according to the differences in the endothelial cell density, as determined by SEM imaging. We show that this spectroscopic difference is statistically significant and can be used to assess the intactness of the endothelial layer. These results demonstrate that THz can noninvasively assess the corneal endothelium and provide valuable complimentary information for the study and diagnosis of corneal diseases that perturb the tissue hydration.https://www.mdpi.com/1424-8220/22/23/9071terahertz time domain spectroscopycorneal endotheliumcorneal tissue hydrationintraocular pressurecorneal edema |
| spellingShingle | Andrew Chen Zachery B. Harris Arjun Virk Azin Abazari Kulandaiappan Varadaraj Robert Honkanen Mohammad Hassan Arbab Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines Sensors terahertz time domain spectroscopy corneal endothelium corneal tissue hydration intraocular pressure corneal edema |
| title | Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines |
| title_full | Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines |
| title_fullStr | Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines |
| title_full_unstemmed | Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines |
| title_short | Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines |
| title_sort | assessing corneal endothelial damage using terahertz time domain spectroscopy and support vector machines |
| topic | terahertz time domain spectroscopy corneal endothelium corneal tissue hydration intraocular pressure corneal edema |
| url | https://www.mdpi.com/1424-8220/22/23/9071 |
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