SAT-584 Headache, Diplopia, and Ophthalmoplegia, and Eye Pain in a Well-Controlled Diabetic Patient: An Important Consideration in the Differential Diagnosis

Abstract Disclosure: A. Lazarev: None. A 76-year-old female with a history of type 2 diabetes mellitus and hypertension presented to the emergency room (ER) with complaints of headache, nausea and vomiting, double vision, and pain in her right eye (described as "someone is sucking it out") that had been ongoing for six days. She also noted that her right eye was deviating to the right side and was unable to move correctly. Initially, she visited a different ER and was sent home with antibiotics for a presumed eye infection; however, her symptoms failed to improve. It was noted that her pupils were reactive. She returned to the ER and was admitted to the hospital to rule out a stroke. Both CT and MRI of the head did not show acute hemorrhagic or ischemic changes, although the MRI showed a few widely scattered high T2 signal hyperintensities within the periventricular white matter, possibly related to old ischemic injury or migraine headache. MRA of the head and neck was unremarkable, as was the MRI of the orbits. MRI of the spine showed no evidence of demyelinating disease but revealed degenerative changes in the cervical, thoracic, and lumbar spine, as well as a small focus of cord edema or myelomalacia at C5-C6 on the left. Her labs showed an HbA1c of 5.4%. A lumbar puncture was performed and revealed colorless, slightly cloudy cerebrospinal fluid (CSF) with 7 RBCs and 6 WBCs per microliter, as well as a total protein of 103.8 mg/dL and glucose of 81 mg/dL. The CSF cytology examination was negative for malignancy or inflammation. Her ESR, CRP, RPR, as well as CSF tests for HSV, NMO-IgG antibodies, VDRL, and cultures were all negative. She received IV methylprednisolone at pulse doses during her hospital stay, which was later tapered to prednisone 60 mg daily upon discharge. The patient was discharged with an eye patch with follow-up appointments with an ophthalmologist and neurologist. The ophthalmologist discontinued prednisone due to its effect on her blood glucose levels. Two months later, her symptoms had completely resolved: she no longer experienced diplopia, and her extraocular movements were intact. She also reported having had a similar episode more than twenty years ago. At this point, the episode was believed to be related to isolated right oculomotor nerve palsy, the most common cranial mononeuropathy observed in diabetic patients. Isolated oculomotor nerve (CN III) mononeuropathy can be a challenging diagnosis in diabetic patients and may lead to extensive diagnostic testing. Pathophysiology of it is related to infarction of vasa nervorum of CN III with the sparing of peripheral fibers of the nerve which results in pupillary sparing. The recurrence of cranial mononeuropathies in diabetic patients warrants further investigation. Despite that it might mimic multiple other important neurologic disorders, isolated oculomotor nerve mononeuropathy is an important differential to consider while maintaining a cost-effective approach to the diagnosis. Presentation: Saturday, July 12, 2025