👉 The oval fluid, also known as the oval sinus or oval space, is a thin, transparent, and slightly gelatinous fluid found in the cranial cavity, specifically within the lateral walls of the fourth ventricle and the posterior horns of the third ventricle. This fluid plays a crucial role in cushioning the brain and spinal cord, facilitating smooth movement of cerebrospinal fluid (CSF) through the ventricular system, and maintaining a stable environment for neural tissues. It also helps in the distribution of nutrients and waste products, and its oval shape contributes to the structural integrity of the ventricular system.