Diplopia Rhinoceros.

Abstract: Bilateral cranial nerve VI palsy is a rare neuro-ophthalmological presentation often associated with systemic or intracranial pathologies. In diabetic patients, cranial neuropathies can occur due to immune suppression, ischemia, or infectious complications. This case highlights the interplay of poorly controlled type 2 diabetes mellitus (T2DM), sinusitis, and skull base inflammation leading to bilateral lateral rectus palsy. A 56-year-old postmenopausal woman presented with a 10-day history of headache, an 8-day history of right-sided facial pain, and progressive binocular diplopia over 5 days. Initial evaluation revealed poorly controlled T2DM (blood glucose: 256 mg/dL) and hypertension. Neurological examination identified bilateral esotropia, limited abduction, and confirmed bilateral cranial nerve VI palsy. Imaging revealed bilateral ethmoidal and sphenoidal sinusitis with skull base inflammation. The patient had a concurrent diagnosis of esophageal candidiasis. The findings suggested diabetic predisposition to infection leading to sinusitis-related skull base osteitis and cranial neuropathy. Cranial nerve VI is anatomically vulnerable to ischemic and compressive injury due to its long intracranial course and proximity to the clivus and sphenoid sinus. Chronic hyperglycemia exacerbates susceptibility to infections and ischemia by impairing immune responses and inducing microvascular damage. The patient was treated with glycemic optimization, antimicrobial therapy for sinusitis, and antifungal agents for candidiasis. Multidisciplinary care ensured systemic and local disease control, preventing further complications. This case underscores the importance of considering neuro-ophthalmological complications in diabetic patients presenting with cranial nerve involvement and systemic infection. It highlights the need for timely diagnosis and targeted management to prevent permanent neurological deficits. Further studies are warranted to explore the pathophysiology and optimal treatment approaches for such rare diabetic complications.