| (1) Trauma: |
| (2) Vascular: |
| Intracavernous carotid artery aneurysm |
| Posterior cerebral artery aneurysm |
| Carotid-cavernous fistula |
| Carotid-cavernous thrombosis |
| Posterior communicating artery aneurysm |
| Internal carotid artery dissection |
| (3) Neoplasm: |
| Primary intracranial tumour |
| Pituitary adenoma |
| Meningioma |
| Craniopharyngioma, others |
| Primary cranial tumour |
| Chordoma, others |
| Local metastases |
| Nasopharyngeal tumour |
| Squamous cell carcinoma |
| Distant metastases |
| Lymphoma |
| Multiple myeloma |
| Carcinomatous metastases |
| (4) Inflammation, infection: |
| Bacterial |
| Contiguous sinusitis |
| Mucocele (sphenoid sinus) |
| Periostitis |
| Abcess |
| Viral |
| Herpes zoster |
| Fungal |
| Mucormycosis, Actinomycosis |
| Spirochetal |
| Treponema pallidum |
| Mycobacterial |
| Mycobacterium tuberculosis |
| Others |
| Sarcoidosis |
| Granulomatosis with polyangiitis |
| Eosinophilic granuloma |
| Tolosa-Hunt syndrome |
| Orbital pseudotumor |
| (5) Miscellaneous: |
| Diabetic ophthalmoplegia |
| Ophthalmoplegic migraine |
| Giant cell arteritis |
