Orbital compartment syndrome secondary to retrobulbar hematoma after infratrochlear nerve block for nasolacrimal probing.

After infratrochlear nerve block for nasolacrimal probing, sudden vision loss, proptosis, pain, loss of light reflexes, and a total limitation of ocular movement was observed in a 71-year-old female patient. She was diagnosed with retrobulbar hemorrhage and orbital compartment syndrome (OCS). Lateral canthotomy, cantholysis, and medial orbitotomy were performed on the patient. She was not taking any oral anticoagulant medication and did not have any disease other than hypothyroidism and systemic hy-pertension. All the clinical findings returned to normal right after the intervention except mild ptosis (~1 mm), which persisted for 2 months. All patients scheduled for periocular anesthesia should be questioned about using oral anticoagulant medications, and the possibility of serious complications should be kept in mind even for patients without any risk factors. Patients with OCS secondary to retrobulbar hemorrhage should be surgically managed within the critical window (90 min) to prevent any irrevers-ible optic nerve injury.