Floor Of Fourth Ventricle Ppt

The features of the lower part of the floor of fourth ventricle resemble with that of a pen nib hence it is called calamus scriptorius 17.

Floor of fourth ventricle ppt.

Projection of the ventricles onto the left surface of the brain. Boundaries floor of 4 th ventricle 8. The whole floor is split into left and right symmetrical halves by a median sulcus which stretches from the aperture of the aqueduct of the midbrain above to the commencement of the central canal below. The fourth ventricle is the last in the system it receives csf from the third ventricle via the cerebral aqueduct.

The caudal tip of the fourth ventricle where it becomes the central canal is known as the obex. The fourth ventricle has an anterior ventral floor with a characteristic diamond shape named the rhomboid fossa and a posterior dorsal tent shaped roof. From the 4th ventricle the fluid drains into two places. It lies within the brainstem at the junction between the pons and medulla oblongata.

The superior pontine part of the floor begins at the aqueduct and expands to the lower margin of the cerebellar peduncles. The fourth ventricle contains cerebrospinal fluid. The obex is also a. Features of the floor of the fourth ventricle rhomboid fossa the floor of the 4th ventricle displays the following features.

Fourth ventricle central canal fourth ventricle mesencephalic aqueduct third ventricle position situated ventral to cerebellum and dorsal to pons and cranial half of medulla 5. The inferolateral margins marked by a narrow white ridge called taenia. It has a diamond shape and is located in the upper portion of the medulla. Exposure of the fourth ventricle was satisfactory in all of the patients and the floor of the fourth ventricle could be visualized early and be protected.

4 1 lateral walls of fourth ventricle. Eor and outcomes were satisfactory in 90 of patients including those harboring large tumors or lesions attached to the lateral or superolateral recesses of the ventricle. The fourth ventricle has a roof at its upper posterior surface and a floor at its lower anterior surface and side walls formed by the cerebellar peduncles nerve bundles joining the structure on the posterior side of the ventricle to the structures on the anterior side. Csf produced and or flowing into the fourth ventricle can exit to the subarachnoid space through lateral apertures and a single median aperture located in the inferiorportion of the roof.

Specifically it spans from the obex an area in the medulla. 4 2 floor or ventral wall of fourth ventricle 4 3 roof of the fourth ventricle. The glistening white floor of the fourth ventricle is the posterior surface of the brain stem. Central spinal canal bathes the spinal cord.

Mri scan of head in sagittal plane. The two taenia meet at the inferior angle of the ventricle to form a small fold called obex.