Indolent corneal ulcers\u2014also known as refractory ulcers, \u201cboxer\u201d ulcers, spontaneous chronic corneal epithelial defects, and recurrent erosions\u2014are a special type of superficial ulcer. They are always nonhealing, superficial corneal ulcers with loose edges and can have varying amounts of ocular discomfort, a characteristic \u201chalo\u201d stain pattern, and corneal vascularization. Indolent ulcers are never infected.<\/p>\n
It is critical to rule out other underlying causes before diagnosing an indolent ulcer. Always look for reasons that an ulcer may not be healing. As with many ophthalmic conditions, indolent ulcers can often be managed in a primary care setting. However, accurate diagnosis, appropriate therapies, and proper postoperative care are critical for successful outcomes. A variety of medical and surgical options are available for the treatment of indolent ulcers in a general practice setting, including cotton-tipped applicator debridement, grid keratotomy, and diamond burr debridement.<\/p>\n
Take-Home Points<\/strong><\/p>\n The cornea is the transparent, anterior portion of the fibrous<\/span> tunic of the globe. Damage to the cornea, resulting in epithelial cell loss with exposed corneal stroma, creates an ulcer on the corneal surface. Squinting (blepharospasm) or holding an eye shut and tearing (epiphora) are often the signs owners will first notice in pets with corneal ulcers. Fluorescein stain uptake in the ulcerated region confirms the diagnosis of an ulcer. Categorization of the ulcer is based on a combination of clinical signs and visual inspection of the eye.<\/span><\/p>\n Indolent corneal ulcers, also known as refractory ulcers, \u201cboxer\u201d ulcers, spontaneous chronic corneal epithelial defects (SCCEDs), and recurrent erosions, are a special type of superficial ulcer that fails to resolve through the normal wound-healing process.1<\/sup> Hallmark clinical and histologic features of SCCEDs include a superficial corneal ulcer that (1) does not extend into the stroma; (2) is associated with redundant, nonadherent corneal epithelial borders that may be associated with an acellular hyaline zone in the anterior stroma; (3) persists for weeks or months if not adequately addressed; and (4) may or may not include neovascularization and edema.2-8<\/sup> <\/span><\/p>\n The underlying pathophysiology of SCCEDs is not completely understood, and there is some thought that these ulcers may be the shared end result of a variety of pathways.1<\/sup> Ultimately, indolent corneal ulcers result from dysmaturation of corneal epithelia that do not properly attach to the underlying stroma of the eye, creating a lesion composed of loose, poorly adhered epithelia overlaying corneal stroma (lipping).1,9<\/sup><\/span><\/p>\n Nonhealing ulcers are often incorrectly labeled as \u201cindolent\u201d without exclusion of other causes of improper healing first, which can lead to inappropriate treatments and catastrophic consequences for the affected eye. Possible underlying issues that could be the cause of a nonhealing ulcer aside from the category of \u201cindolent\u201d include infection, tear film deficiencies (qualitative or quantitative), exposure due to conformation or buphthalmia, a foreign body, an eyelid mass<\/a>, aberrant hairs (ectopic cilia, distichia, trichiasis), and entropion.2<\/sup> It is critical to rule out underlying causes <\/i>before<\/i><\/b> a diagnosis of an indolent ulcer. Always look for reasons that an ulcer may not be healing, especially in younger animals.<\/i><\/span><\/p>\n As with many ophthalmic conditions, indolent ulcers can often be managed in a primary care setting. However, accurate diagnosis, appropriate therapies, and proper postoperative care are critical for successful outcomes. This article discusses diagnosis of indolent ulcers, treatment options, and conditions for referral.<\/span><\/p>\n Indolent corneal ulcers are always nonhealing, superficial ulcers with loose edges and can have varying amounts of ocular discomfort, a characteristic \u201chalo\u201d stain pattern, and corneal vascularization (<\/strong><\/span>FIGURE 1<\/span><\/strong>)<\/strong>. They are most commonly found in middle-aged to older dogs (average age of 8 to 9 years), although they can be found at any age.7,9-11<\/sup> Indolent ulcers have been documented in almost every canine breed, but some studies suggest that boxers may be overrepresented.8,11<\/sup> <\/span><\/p>\n\n
Diagnosis of Indolent Corneal Ulcers<\/h2>\n
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2023\/04\/FooteMcIntosh_TVPMayJune23_IndolentUlcers_Figure1A.png\")
Figure 1. Examples of indolent ulcers on presentation, prior to treatment, with variable amounts of edema, vascularization, and scrolled epithelium. (A) Note the \u201chalo\u201d effect (arrow) where stain has leaked under the loose ulcer margins, but no corneal vessels or scrolled epithelium.<\/span><\/a><\/div><\/div>
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2023\/04\/FooteMcIntosh_TVPMayJune23_IndolentUlcers_Figure1B.png\")
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2023\/04\/FooteMcIntosh_TVPMayJune23_IndolentUlcers_Figure1C.png\")
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2023\/04\/FooteMcIntosh_TVPMayJune23_IndolentUlcers_Figure1D.png\")