Ocular phenomena can be one of the first signs of a serious disease. As Jim Williamson, OD, explained in his course “Seeing Double: The Urgent and Chronic Causes of Diplopia,” at the Southeastern Educational Congress of Optometry (SECO) 2021 meeting, several causes of diplopia, or “double vision,” can be deadly.
The course offered attendees a review of the medical differential diagnosis and treatment strategies for the root causes of diplopia. Clinicians must first rule out urgent medical causes and only then consider whether a chronic cause is responsible.
Critical conditions diplopia can signal may include third nerve palsy (CNIII Palsy), granulomatosis with polyangiitis (GPA), and thyroid-associated orbitopathy (TAO).
In CNIII Palsy, intracranial aneurysms jeopardize the oculomotor nerve. While the standard of care for detecting aneurysms is cerebral digital subtraction angiography (DSA), Dr Williamson recommends a preliminary course of action using magnetic resonance angiogram (MRA) if there are no contraindications and then follow with computed tomography angiography (CTA) if no intracranial aneurysms appear.
He also reviewed vasculitides, such as GPA, polyarteritis nodosa, and giant cell arteritis (GCA).
GPA, chronic inflammation coinciding with granuloma formation, is fatal if it is not treated. Many patients have ocular and orbital symptoms, including diplopia, which is caused by affected extraocular muscles and superior orbital fissure. Dr Williamson explained appropriate testing and potential treatments, which include immunosuppressives and rituximab therapy.
Thyroid-associated orbitopathy (TAO) is another possible cause of diplopia. In this disorder, eye movement is limited because of later-stage fibrosis or extraocular muscles’ inflammation. It includes both active phases and inactive phases, and smoking can reactivate it.
Dr Williamson also covered several other diseases and conditions in the course, including traumatic brain injury (TBI), Parkinson’s disease, dragged-fovea diplopia syndrome, and supranuclear lesions, such as internuclear ophthalmoplegia (INO) and skew deviation.
While not all patients with double vision have an underlying neurological or systemic disease that could be life-threatening, it is absolutely essential for optometrists to treat each unexplained case as a priority until they can establish the patient’s immediate risk.
Williamson J. Seeing Double: The Urgent and Chronic Causes of Diplopia. Presented at: Southeastern Educational Congress of Optometry (SECO) 2021 Annual Meeting; April 28-May 2, 2021; Atlanta, GA. Course 120.
This article originally appeared on Ophthalmology Advisor