👉 Subvitreousness is a medical condition in which there is fluid or pus in the space between brain cells, usually in the part of the skull called the subarachnoid space. It can occur due to various causes such as tumors, infections, or even chronic inflammation. The fluid is often produced by the brain itself and is known as cerebrospinal fluid (CSF). This condition can cause symptoms like headaches, fever, and sensitivity to light, especially in those with certain