1
|
Chin JY, Liu C, Lee IXY, Lin MTY, Cheng CY, Wong JHF, Teo CL, Mehta JS, Liu YC. Impact of Age on the Characteristics of Corneal Nerves and Corneal Epithelial Cells in Healthy Adults. Cornea 2024; 43:409-418. [PMID: 37643477 PMCID: PMC10906190 DOI: 10.1097/ico.0000000000003363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/26/2023] [Accepted: 07/02/2023] [Indexed: 08/31/2023]
Abstract
PURPOSE The aim of this study was to investigate age-related changes in corneal nerves and corneal epithelial cell parameters and to establish age-adjusted reference values. METHODS A total of 7025 corneal nerve images and 4215 corneal epithelial images obtained using in vivo confocal microscopy from 281 eyes of 143 healthy participants were included. Seven corneal nerve parameters and 3 corneal epithelial cell parameters were quantified using 2 automatic analytic software and analyzed across 6 age groups ranging from 21 to 80 years. RESULTS There was a declining trend in all 7 nerve parameters with advancing age. In particular, corneal nerve fiber length and corneal nerve fiber density demonstrated a significant decrease in subjects aged 65 years or older compared with subjects younger than 65 years (10.8 ± 2.6 mm/mm 2 vs. 9.9 ± 2.0 mm/mm 2 , P = 0.011 in corneal nerve fiber length; 15.8 ± 5.2 fibers/mm 2 vs. 14.4 ± 4.3 fibers/mm 2 , P = 0.046 in corneal nerve fiber density), whereas corneal nerve fractal dimension demonstrated a borderline significant decrease ( P = 0.057). Similarly, there was a general declining trend in all epithelial cell parameters with advancing age. Corneal epithelial cell circularity was significantly lower in subjects aged 65 years and older as compared to subjects younger than 65 years (0.722 ± 0.021 μm 2 vs. 0.714 ± 0.021 μm 2 ; P = 0.011). CONCLUSIONS Advancing age results in reduced corneal nerve metrics and alteration of corneal cell morphology. Aging effects should be considered when evaluating patients with corneal neuropathy.
Collapse
Affiliation(s)
- Jia Ying Chin
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
| | - Chang Liu
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
| | - Isabelle Xin Yu Lee
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
| | - Molly Tzu Yu Lin
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
| | - Ching-Yu Cheng
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
- Epidemiology Group, Singapore Eye Research Institute, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | - Jipson Hon Fai Wong
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
| | - Cong Ling Teo
- Epidemiology Group, Singapore Eye Research Institute, Singapore
| | - Jodhbir S. Mehta
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
- Department of Cornea and External Eye Disease, Singapore National Eye Centre, Singapore; and
| | - Yu-Chi Liu
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
- Department of Cornea and External Eye Disease, Singapore National Eye Centre, Singapore; and
- Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan
| |
Collapse
|
2
|
Liu C, Lin MTY, Lee IXY, Wong JHF, Lu D, Lam TC, Zhou L, Mehta JS, Ong HS, Ang M, Tong L, Liu YC. Neuropathic Corneal Pain: Tear Proteomic and Neuromediator Profiles, Imaging Features, and Clinical Manifestations. Am J Ophthalmol 2024; 265:6-20. [PMID: 38521157 DOI: 10.1016/j.ajo.2024.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 01/05/2024] [Accepted: 03/15/2024] [Indexed: 03/25/2024]
Abstract
PURPOSE To investigate the tear proteomic and neuromediator profiles, in vivo confocal microscopy (IVCM) imaging features, and clinical manifestations in neuropathic corneal pain (NCP) patients. DESIGN Cross-sectional study. METHODS A total of 20 NCP patients and 20 age-matched controls were recruited. All subjects were evaluated by corneal sensitivity, Schirmer test, tear break-up time, and corneal and ocular surface staining, Ocular Surface Disease Index and Ocular Pain Assessment Survey questionnaires were administered, as well as IVCM examinations for corneal nerves, microneruomas, and epithelial and dendritic cells. Tears were collected for neuromediator and proteomic analysis using enzyme-linked immunosorbent assay and data-independent acquisition mass spectrometry. RESULTS Burning and sensitivity to light were the 2 most common symptoms in NCP. A total of 188 significantly dysregulated proteins, such as elevated metallothionein-2, creatine kinases B-type, vesicle-associated membrane protein 2, neurofilament light polypeptide, and myelin basic protein, were identified in the NCP patients. The top 10 dysregulated biological pathways in NCP include neurotoxicity, axonal signaling, wound healing, neutrophil degradation, apoptosis, thrombin signaling mitochondrial dysfunction, and RHOGDI and P70S6K signaling pathways. Compared to controls, the NCP cohort presented with significantly decreased corneal sensitivity (P < .001), decreased corneal nerve fiber length (P = .003), corneal nerve fiber density (P = .006), and nerve fiber fractal dimension (P = .033), as well as increased corneal nerve fiber width (P = .002), increased length, total area and perimeter of microneuromas (P < .001, P < .001, P = .019), smaller corneal epithelial size (P = .017), and higher nerve growth factor level in tears (P = .006). CONCLUSIONS These clinical manifestations, imaging features, and molecular characterizations would contribute to the diagnostics and potential therapeutic targets for NCP.
Collapse
Affiliation(s)
- Chang Liu
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Cornea and Refractive Surgery Group (C.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore
| | - Molly Tzu-Yu Lin
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore
| | - Isabelle Xin Yu Lee
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore
| | - Jipson Hon Fai Wong
- Clinical Research Platform (J.H.F.W.), Singapore Eye Research Institute, Singapore
| | - Daqian Lu
- Centre for Myopia Research (D.L., T.C.L.), School of Optometry, Hong Kong Polytechnic University, Hong Kong
| | - Thomas Chuen Lam
- Centre for Myopia Research (D.L., T.C.L.), School of Optometry, Hong Kong Polytechnic University, Hong Kong; Centre for Eye and Vision Research (CEVR) (T.C.L.), Hong Kong
| | - Lei Zhou
- School of Optometry (L.Z.), Department of Applied Biology and Chemical Technology, Research Centre for SHARP Vision (RCSV); The Hong Kong Polytechnic University, Hong Kong
| | - Jodhbir S Mehta
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Cornea and Refractive Surgery Group (C.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Department of Cornea and External Eye Disease (J.S.M., H.S.O., M.A., L.T., Y.-C.L.), Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program (J.S.M., H.S.O., M.A., Y.-C.L.), Duke-NUS Medical School, Singapore
| | - Hon Shing Ong
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Cornea and Refractive Surgery Group (C.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Department of Cornea and External Eye Disease (J.S.M., H.S.O., M.A., L.T., Y.-C.L.), Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program (J.S.M., H.S.O., M.A., Y.-C.L.), Duke-NUS Medical School, Singapore
| | - Marcus Ang
- Department of Cornea and External Eye Disease (J.S.M., H.S.O., M.A., L.T., Y.-C.L.), Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program (J.S.M., H.S.O., M.A., Y.-C.L.), Duke-NUS Medical School, Singapore
| | - Louis Tong
- Department of Cornea and External Eye Disease (J.S.M., H.S.O., M.A., L.T., Y.-C.L.), Singapore National Eye Centre, Singapore; Ocular Surface Research Group (L.T.), Singapore Eye Research Institute, Singapore; Eye Academic Clinical Program (L.T.), Duke-NUS Medical School, Singapore; Department of Ophthalmology (L.T.), Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yu-Chi Liu
- From Tissue Engineering and Cell Therapy Group (C.L., M.T.-Y.L., I.X.Y.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Cornea and Refractive Surgery Group (C.L., J.S.M., H.S.O., Y.-C.L.), Singapore Eye Research Institute, Singapore; Department of Cornea and External Eye Disease (J.S.M., H.S.O., M.A., L.T., Y.-C.L.), Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program (J.S.M., H.S.O., M.A., Y.-C.L.), Duke-NUS Medical School, Singapore; Department of Ophthalmology (Y.-C.L.), National Taiwan University, Taiwan.
| |
Collapse
|