The first thing to consider in neurology is the onset of migraine when a patient presents with left eye swelling and pain accompanied by a left-sided headache. Migraine is usually dominated by migraines, and in severe cases, eye distension can occur. In this case, patients are advised to take oral aminoglutethimide tablets and ibuprofen extended-release capsules to relieve the headache. Also consider the discomfort caused by increased intraocular pressure, such as glaucoma on the left side, elevated intraocular pressure, resulting in the appearance of left-sided eye distention and pain, as well as head distension, which requires ophthalmic surgery to improve. If the discomfort is caused by painful ocular muscle paralysis, a cavernous sinus MRI and cerebrospinal fluid examination should be performed to clarify the diagnosis and provide treatment.