Fundus (brain)

Fundus (brain)

The Fundus is a term used in neuroanatomy to refer to the bottom or base of certain structures within the brain. The term is most commonly used in reference to the ventricular system of the brain, specifically the floor of the third ventricle and the fourth ventricle.

Anatomy

The fundus of the third ventricle is located at the bottom of the ventricle, and is formed by the hypothalamus. It contains several important structures, including the mammillary bodies, which are involved in memory processing, and the tuber cinereum, which connects the hypothalamus to the pituitary gland.

The fundus of the fourth ventricle is located at the bottom of the ventricle, and is formed by the medulla oblongata and pons, two structures of the brainstem. It contains the obex, a marker for the lower limit of the fourth ventricle, and the area postrema, a region of the brain involved in the control of vomiting.

Clinical significance

Abnormalities in the fundus of the third or fourth ventricle can lead to a variety of neurological conditions. For example, tumors in the fundus of the third ventricle can cause hydrocephalus, a condition characterized by an accumulation of cerebrospinal fluid in the brain. Similarly, lesions in the fundus of the fourth ventricle can lead to ataxia, a lack of muscle coordination, or nystagmus, a condition characterized by involuntary eye movements.

See also

• Ventricular system
• Third ventricle
• Fourth ventricle
• Brainstem
• Hypothalamus