2020–2021 BCSC Basic and Clinical Science Course™
8 External Disease and Cornea
Chapter 14: Clinical Aspects of Toxic and Traumatic Injuries of the Anterior Segment
Concussive (Blunt) Trauma
Iridodialysis and Cyclodialysis
Iridodialysis
Blunt trauma may cause iridodialysis, or traumatic separation of the iris root from the ciliary body (Fig 14-14). Anterior segment hemorrhage often ensues, and the iridodialysis may not be recognized until the hyphema has cleared. A small iridodialysis requires no treatment. A large iridodialysis may cause polycoria, polyopia, and monocular diplopia, requiring surgical repair (Figs 14-15, 14-16) (see Surgical Management later in the chapter). If possible, the iridodialysis should be repaired within a few weeks of the injury, because prolonged contracture of the radial iris fibers may prevent a round pupil after normal iris anatomy is reestablished.
Cyclodialysis
Traumatic cyclodialysis is characterized by separation of the ciliary body from its attachment to the scleral spur, resulting in a cleft. A hyphema may result from the tearing of the tissue. Gonioscopically, this cleft appears as a gap at the posterior edge of the scleral spur from posterior displacement of the ciliary body band. Sclera may be visible through the gap. Ultrasound biomicroscopy can be useful in identifying the location and extent of the cyclodialysis (Fig 14-17). A cyclodialysis cleft can cause increased uveoscleral outflow, leading to chronic hypotony, and macular edema. If treatment with topical cycloplegics does not suffice, closure may be attempted using an argon laser, diathermy, cryotherapy, or direct suturing. If repair is necessary, it should be performed after resolution of the hyphema.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.