ArticleNPJ Parkinson's disease2021
Corneal nerve fiber loss relates to cognitive impairment in patients with Parkinson's disease.
Article in NPJ Parkinson's disease, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 28 citations in OpenAlex.
- Deep learning-based segmentation and density estimation of corneal nerves and dendritic cells from In Vivo confocal microscopy images.Scientific reports · 2026Article
- Ocular Surface Changes Associated with Neurological Diseases.Medicina (Kaunas, Lithuania) · 2025Review
- Cornea Nerves Can Identify Different Types of Parkinson's Disease.Investigative ophthalmology & visual science · 2025Article
- Corneal confocal microscopy differentiates patients with secondary parkinsonism from idiopathic Parkinson's disease.NPJ Parkinson's disease · 2025Article
- Obesity negatively impacts corneal nerves in patients with diabetes mellitus.Eye and vision (London, England) · 2025Article
- Corneal confocal microscopy may help to distinguish Multiple System Atrophy from Parkinson's disease.NPJ Parkinson's disease · 2024Article
- Corneal confocal microscopy demonstrates sensory nerve loss in children with autism spectrum disorder.PloS one · 2023Article
- Chaudhuri's Dashboard of Vitals in Parkinson's syndrome: an unmet need underpinned by real life clinical tests.Frontiers in neurology · 2023Review
- The severity of corneal nerve loss differentiates motor subtypes in patients with Parkinson's disease.Therapeutic advances in neurological disorders · 2023Article
- Ocular Surface Features in Patients with Parkinson Disease on and off Treatment: A Narrative Review.Life (Basel, Switzerland) · 2022Review
- Artificial Intelligence and Corneal Confocal Microscopy: The Start of a Beautiful Relationship.Journal of clinical medicine · 2022Review
- Corneal confocal microscopy differentiates patients with Parkinson's disease with and without autonomic involvement.NPJ Parkinson's disease · 2022Article
- Small fiber neuropathy for assessment of disease severity in amyotrophic lateral sclerosis: corneal confocal microscopy findings.Orphanet journal of rare diseases · 2022Article
- Association of corneal endothelial cell morphology with neurodegeneration in mild cognitive impairment and dementia.Alzheimer's & dementia (New York, N. Y.)Article
Corrections and comments
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Authors and funding
9 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Cognitive impairment in Parkinson's disease (PD) adversely influences quality of life. There is currently no available biomarker to predict cognitive decline in PD. Corneal confocal microscopy (CCM) has been used as a non-invasive tool for quantifying small nerve damage in PD. The present study investigated whether corneal nerve measures were associated with cognitive function in PD. Patients with PD were classified into those with normal cognitive function (PD-CN), mild cognitive impairment (PD-MCI), and dementia (PDD). Corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and corneal nerve fiber length (CNFL) were quantified with CCM and compared with a control group. Sixty-five PD patients and thirty controls were studied. CNFD was decreased and CNBD was increased in PD patients compared to controls (P < 0.05). CNBD and CNBD/CNFD ratio was higher in PD-CN compared to controls. CNFD was positively correlated with the Montreal cognitive assessment (MoCA) score (r = 0.683, P < 0.001), but negatively associated with unified Parkinson disease rating scale (UPDRS)-part III (r = -0.481, P < 0.001) and total UPDRS scores (r = -0.401, P = 0.001) in PD patients. There was no correlation between CNFD and Levodopa equivalent daily dose (LEDD) (r = 0.176, P = 0.161). CNFD, CNBD, CNFL, and CNBD/CNFD ratio was lower with increasing Hoehn and Yahr stage. PD patients show evidence of corneal nerve loss compared with controls and corneal nerve parameters are associated with the severity of cognitive and motor dysfunction in PD. CCM could serve as an objective in vivo ophthalmic imaging technique to assess neurodegeneration in PD.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.