2020–2021 BCSC Basic and Clinical Science Course™
4 Ophthalmic Pathology and Intraocular Tumors
Part I: Ophthalmic Pathology
Chapter 4: Wound Repair
General Aspects of Wound Repair
The purpose of wound healing is to restore the anatomical and functional integrity of an organ or tissue as quickly as possible. Although it is a common physiologic process, wound healing involves a complicated sequence of tissue events. The process may take many months, and the end result is typically a scar (Fig 4-1). When wound healing occurs in the eye, it can interfere with vision. There are 3 general phases of wound healing:
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Inflammatory phase: The acute inflammatory phase may last from minutes to hours. Blood clots quickly in adjacent vessels in response to tissue activators. Neutrophils and fluid enter the extravascular space. Histiocytes (also called macrophages) remove debris from the damaged tissues, and new vessels form. Fibroblasts begin to produce collagen, the main structural protein in connective tissues. Collagen plays multiple roles in wound healing, including interacting with platelets to initiate the inflammatory phase and functioning as a scaffold or guide for fibroblast migration.
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Proliferative phase: Regeneration is the replacement of lost cells and occurs only in tissues composed of cells capable of undergoing mitosis throughout life (eg, epithelial cells, fibroblasts).
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Remodeling phase: Repair is the process of restructuring of tissues to recapitulate normal tissue and typically results in a fibrous scar. In this final phase, contraction causes the reparative tissues to shrink so that the scar is smaller than the surrounding uninjured tissues. This process may affect adjacent tissues and structures. Both repair and contraction of wounds are highly dependent on fibroblasts.
Excerpted from BCSC 2020-2021 series: Section 4 - Ophthalmic Pathology and Intraocular Tumors. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.