There are two main types of intraocular<unk> s: primary central nervous system involvement (PCNSL) and primary central nervous system with ocular involvement (PCNSLO). The difference between PCNSL and PCNSLO is that PNSCL involves the central nervous system, while PCNSLO does not. 56-86% of<unk> s are classified PCNSL and 15-25% are classified PCNSLO. PCNSLO is common in people who are severely immunosuppressed. Symptoms of this form of ocular<unk>  include painless decreased vision, sensitivity to light, a red eye, and floaters. Diagnosis is difficult due to its gradual onset and the fact that the symptoms are the same as other diseases. PCNSLO is usually bilateral, but sometimes grows unevenly. Like other metastatic tumors of the eye, it is usually confined to the choroid.
Orbital lymphoma
Orbital cellulitis
Intraocular lymphoma
Periorbital cellulitis
Labyrinthitis
Optic papillitis
Idiopathic orbital inflammatory disease
Vestibular adenitis