10
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Corneal Innervation and Sensation: The Eye and Beyond

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          The cornea is one of the most densely innervated and sensitive tissues in the body. In addition to their important sensory functions, corneal nerves induce reflex tear production, blinking, and the release of trophic factors – all of which combined help to maintain the structural and functional integrity of the surface of the eye. Consequently, damage to corneal nerves as a result of disease, surgery, or trauma can lead to diminished corneal sensitivity, epithelial defects, and possible blindness. In this review, we describe commonly used tools that have provided considerable new information on corneal architecture and sensation in healthy and diseased corneas, with special emphasis on changes seen in herpes zoster ophthalmicus, corneal and other therapeutic ocular procedures, antiglaucoma medical therapy, aging, and diabetes. With its potential applications ranging from managing ocular-specific to systemic diseases, the study of corneal innervation has implications for future therapies extending beyond just the eye itself.

          Related collections

          Most cited references 107

          • Record: found
          • Abstract: found
          • Article: not found

          Corneal nerves: structure, contents and function

          Experimental Eye Research, 76(5), 521-542
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Prevalence of ocular surface disease in glaucoma patients.

            To examine the prevalence of ocular surface disease (OSD) in glaucoma patients. This was a cross-sectional study. One hundred and one patients, 18 years of age or older, with open-angle glaucoma or ocular hypertension were consecutively recruited for the study. Patients with a history of use of cyclosporine, steroids, topical ocular nonsteroidal anti-inflammatory drugs, or punctal plugs within the last 3 months were excluded. Each patient completed an Ocular Surface Disease Index questionnaire and underwent evaluation by Schirmer test, corneal and conjunctival lissamine green staining, and tear break-up time. Using Ocular Surface Disease Index for measuring symptoms of dry eye, 60 (59%) patients reported symptoms in at least 1 eye. Severe symptoms were reported by 27 (27%) patients. Schirmer testing showed 62 (61%) patients with decrease in tear production in at least 1 eye. Severe tear deficiency was presented in 35 (35%) patients. Corneal and conjunctival lissamine green staining showed positive results in 22 (22%) patients. None had severe staining. Tear break-up time showed abnormal tear quality in 79 (78%) patients and severe decrease in tear quality was found in at least 1 eye in 66 (65%) patients. Multivariate logistic regression models were used to investigate the association between the number of benzalkonium chloride (BAK)-containing eyedrops and results on the clinical tests of OSD. After adjustment for age and sex, each additional BAK-containing eyedrop was associated with an approximately 2 times higher odds of showing abnormal results on the lissamine green staining test (odds ratio=2.03; 95% confidence interval: 1.06 to 3.89; P=0.034). A large proportion of patients with open-angle glaucoma or ocular hypertension had signs and/or symptoms of OSD in at least 1 eye. The coexistence of OSD and the use of BAK-containing medications may impact vision-related quality of life in this patient population.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Surrogate markers of small fiber damage in human diabetic neuropathy.

              Surrogate markers of diabetic neuropathy are being actively sought to facilitate the diagnosis, measure the progression, and assess the benefits of therapeutic intervention in patients with diabetic neuropathy. We have quantified small nerve fiber pathological changes using the technique of intraepidermal nerve fiber (IENF) assessment and the novel in vivo technique of corneal confocal microscopy (CCM). Fifty-four diabetic patients stratified for neuropathy, using neurological evaluation, neurophysiology, and quantitative sensory testing, and 15 control subjects were studied. They underwent a punch skin biopsy to quantify IENFs and CCM to quantify corneal nerve fibers. IENF density (IENFD), branch density, and branch length showed a progressive reduction with increasing severity of neuropathy, which was significant in patients with mild, moderate, and severe neuropathy. CCM also showed a progressive reduction in corneal nerve fiber density (CNFD) and branch density, but the latter was significantly reduced even in diabetic patients without neuropathy. Both IENFD and CNFD correlated significantly with cold detection and heat as pain thresholds. Intraepidermal and corneal nerve fiber lengths were reduced in patients with painful compared with painless diabetic neuropathy. Both IENF and CCM assessment accurately quantify small nerve fiber damage in diabetic patients. However, CCM quantifies small fiber damage rapidly and noninvasively and detects earlier stages of nerve damage compared with IENF pathology. This may make it an ideal technique to accurately diagnose and assess progression of human diabetic neuropathy.
                Bookmark

                Author and article information

                Journal
                Yale J Biol Med
                Yale J Biol Med
                yjbm
                YJBM
                The Yale Journal of Biology and Medicine
                YJBM
                0044-0086
                1551-4056
                28 March 2018
                March 2018
                : 91
                : 1
                : 13-21
                Affiliations
                Department of Ophthalmology and Visual Science, Yale School of Medicine, New Haven, CT
                Author notes
                [* ]To whom all correspondence should be addressed: Ji Liu, MD, 40 Temple St. Department of Ophthalmology and Visual Science, Yale School of Medicine, New Haven, CT 06510; Tel: 203-785-2020, Fax: 203-785-7090, Email: liu.ji@ 123456yale.edu .
                Article
                yjbm91113
                5872636
                Copyright ©2018, Yale Journal of Biology and Medicine

                This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License, which permits for noncommercial use, distribution, and reproduction in any digital medium, provided the original work is properly cited and is not altered in any way.

                Categories
                Review
                Focus: Sensory Biology and Pain

                Comments

                Comment on this article