Assessment of dynamic corneal nerve changes using static landmarks by large-area confocal microscopy-a longitudinal proof-of-concept study.

Background: The purpose of the present proof-of-concept study was to use large-area confocal laser scanning microscopy (CLSM) mosaics to determine the migration rates of nerve branching points in the human corneal subbasal nerve plexus (SNP).

Methods: Three healthy individuals were examined roughly weekly over a total period of six weeks by large-area confocal microscopy of the central cornea. An in-house developed prototype system for guided eye movement with an acquisition time of 40 s was used to image and generate large-area mosaics of the SNP.

Hyperosmolar Tears Induce Functional and Structural Alterations of Corneal Nerves: Electrophysiological and Anatomical Evidence Toward Neurotoxicity.

Purpose: In an effort to elucidate possible neural mechanisms underlying diminished tearing in dry eye disease, this study sought to determine if hyperosmolar tears, a ubiquitous sign of dry eye disease, produce functional changes in corneal nerve responses to drying of the cornea and if these changes correlate with alterations in corneal nerve morphology.

Methods: In vivo extracellular electrophysiological recordings were performed in rat trigeminal ganglion neurons that innervated the cornea before, and up to 3 hours after, the ocular application of continuous hyperosmolar tears or artificial tears. In corollary experiments, immunohistochemical staining was performed to compare corneal nerve morphology in control and in eyes treated with hyperosmolar solutions.

Gross anatomy and morphometric evaluation of the canine lacrimal and third eyelid glands.

Objective: The lacrimal gland (LG) and the third eyelid gland (TELG) are two intraorbital glands that, in dogs, secrete the aqueous component of the tear film. Despite the central importance of these structures for maintaining ocular surface health, the gross anatomy of the glands remains understudied. We investigated the macroscopic morphometric characteristics of the LG and TELG in three different dog breeds.

Loss of corneal sensory nerve fibers in SIV-infected macaques: an alternate approach to investigate HIV-induced PNS damage.

Peripheral neuropathy is the most frequent neurological complication of HIV infection, affecting more than one-third of infected patients, including patients treated with antiretroviral therapy. Although emerging noninvasive techniques for corneal nerve assessments are increasingly being used to diagnose and monitor peripheral neuropathies, corneal nerve alterations have not been characterized in HIV. Here, to determine whether SIV infection leads to corneal nerve fiber loss, we immunostained corneas for the nerve fiber marker βIII tubulin.

Metaherpetic corneal disease in a dog associated with partial limbal stem cell deficiency and neurotrophic keratitis.

Objective: To describe clinical, in vivo confocal microscopic, histopathologic, and immunohistochemical features of a dog with metaherpetic corneal disease that developed subsequent to a protracted episode of canine herpesvirus-1 (CHV-1) dendritic ulcerative keratitis.

Case Description: A 7-year-old, spayed-female, Miniature Schnauzer was treated for bilateral CHV-1 dendritic ulcerative keratitis. Following resolution of ulcerative keratitis, sectoral peripheral superficial corneal gray opacification, vascularization, and pigmentation slowly migrated centripetally to the axial cornea of both eyes.

Anatomy of the human corneal innervation.

The anatomy of the human corneal innervation has been the subject of much investigation; however, a comprehensive description remains elusive. The purpose of the present study was to provide a detailed description of the human corneal innervation using a novel approach involving immunohistochemically stained anterior-cornea whole mounts. Sixteen donor corneas aged 19-78 years were cut with a 6.

Age-related changes in rat corneal epithelial nerve density.

Purpose: To determine the effect of aging on corneal epithelial nerve density in an animal model.

Methods: Corneal whole mounts from rats aged 6, 12, 18, and 24 months were stained immunohistochemically with antisera against the pan-neuronal marker neurotubulin. Epithelial nerve terminals and subbasal nerves in standardized 1-mm(2) central and peripheral zones from each cornea were drawn using a drawing tube attached to a light microscope.

Nerve growth factor and corneal wound healing in dogs.

Nerve growth factor in the tear film and corneal epithelium is hypothesized to play an important role in ocular surface maintenance and corneal wound healing. The purpose of this study was to determine the expression of nerve growth factor and its high affinity (trkA) receptor in tears, cornea, and lacrimal glands of normal dogs, the modulation of nerve growth factor and its trkA receptor during corneal wound healing, and the effect of topical nerve growth factor application on canine corneal epithelial wound healing. In the first of three experiments, the nerve growth factor content of tears, corneal epithelium, lacrimal gland, and 3rd eyelid gland was determined in normal dogs by enzyme-linked immunosorbent assay and the expression of nerve growth factor and its trkA receptor were evaluated in the cornea and lacrimal glands by immunohistochemistry.

Expression and immunolocalization of plasma membrane calcium ATPase isoforms in human corneal epithelium.

Purpose: Plasma membrane Ca2+-ATPases (PMCAs) are integral membrane proteins essential to the control of intracellular Ca2+ ([Ca2+]i) concentration. Four genes encode PMCA proteins termed PMCA1-PMCA4. Little is known about the expression of these isoforms in corneal epithelium (CE).

Corneal nerves: structure, contents and function.

This review provides a comprehensive analysis of the structure, neurochemical content, and functions of corneal nerves, with special emphasis on human corneal nerves. A revised interpretation of human corneal nerve architecture is presented based on recent observations obtained by in vivo confocal microscopy (IVCM), immunohistochemistry, and ultrastructural analyses of serial-sectioned human corneas. Current data on the neurotransmitter and neuropeptide contents of corneal nerves are discussed, as are the mechanisms by which corneal neurochemicals and associated neurotrophins modulate corneal physiology, homeostasis and wound healing.

Effects of cyclophotocoagulation with a neodymium:yttrium-aluminum-garnet laser on corneal sensitivity, intraocular pressure, aqueous tear production, and corneal nerve morphology in eyes of dogs.

Objective: To determine effects of cyclophotocoagulation via administration of 100 J with a neodymium:yttrium aluminum garnet (Nd:YAG) laser on corneal touch threshold (CTT), intraocular pressure (IOP), aqueous tear production, and corneal nerve morphology in eyes of dogs.

Animals: 15 dogs.

Procedure: Noncontact Nd:YAG laser was transsclerally applied (10 applications; 25 W for 0.