Table 2 Patient characteristics for when corneal sensitivity testing is strongly recommended or may be considered

• Persistent epithelial defect that does not improve within 14 days

• Painless, newly observed epithelial defect of unknown etiology

• History of herpetic eye disease

• History of procedures that might have damaged the trigeminal nerve or conditions that might have involved the trigeminal nerve

• Pain in the affected eye and multiple, concurrent risk factors, such as persistent poorly controlled diabetes and either reduced blink or a history of corneal procedures

• Acquired limbal stem cell deficiency

• Newly observed epithelial staining and persistent poorly controlled diabetes

• Persistent poorly controlled diabetes and vision changes not ascribed to diabetic retinopathy or cataract (even in the absence of corneal findings)