Fourth ventricle
- 1. Click to edit Master title style 1 Fourth Ventricle B y : D r A b h i s h e k K u m a r R a i D N B T h i r d y e a r r e s i d e n t S a k r a Wo r l d H o s p i t a l
- 2. Click to edit Master title style 2 The four th ventr ic le is a br oad tent s haped midline c avity, loc ated betw een c er ebellum and br ains tem. C avity of hind br ain. 2 Introduction
- 3. Click to edit Master title style 3 • T h e neur al tube for ms ar ound the four th w eek of ges tation. • Th e c enter, hollow por tion of the neur al tube eventually d e ve lo p s in to th e ve n tr ic u la r s ys te m. • Thre e dilat ions , c a lle d th e pr os enc ephalon , mes enc ephalon, a n d r hombenc ephalon , for m fr om the neur al tube . • W ith in e a c h o f th e s e d ila tio n s th a t d e ve lo p fr o m th e n e u r a l tu b e a r e c a vitie s th a t b e c o me th e ve n tr ic le s . • Th e c avity loc ated in the r hombencephalon bec omes the four th ve n tr ic le . 3 Embryology
- 4. Click to edit Master title style 4 • p o s te r io r infer ior c er ebellar ar ter y ( PIC A ) • a n te r io r infer ior c er ebellar ar ter y ( AIC A) • s u p e r io r c er ebellar ar ter y ( SC A ) . 4 Blood Supply and Lymphatics
- 5. Click to edit Master title style 5 • R e c e s s a r e e xte n s io n o f ma in c a vity o f ve n tr ic le . 1 . Later al - 2 2 . Medial D or s al - 1 3 . Later al D or s al - 2 5 Recess
- 6. Click to edit Master title style 6 Inf c er ebellar pedunc le ( Ventr al) LR Floc c us ( D or s ally) 6 Lateral Recess Reach up to Flocculus Foramen of luschka
- 7. Click to edit Master title style 7 • Me dia l c e re be lla r pe dunc le : extens ion into w hite c or e of c e r e b e llu m. • Lies just in front of Nodule • La t e ra l dors a l re c e s s : • Lies above inferior medullary velum • Lateral to Nodule 7 Recess
- 8. Click to edit Master title style 8 • Su p e r io r • In fe r io r • L a te r a l 8 Angle
- 9. Click to edit Master title style 9 • L a te r a l w a ll • Flo o r • R o o f 9 Boundaries
- 10. Click to edit Master title style 10 • Su p e r o la te r a l • Superior cerebellar peduncle • In fe r o la te r a l • Inferior cerebellar peduncle • Gracile and cuneate tubercle 10 Lateral wall
- 11. Click to edit Master title style 1111 Floor
- 12. Click to edit Master title style 1212 Roof
- 13. Click to edit Master title style 13 1 . Medulloblas tomas 2 . Ependymomas 3 . As tr oc ytomas 4 . D andy- w alk er c ys ts 5 . Metas tas is to c hor oid plexus or ependyma is mos t c ommon in adults 6 . Epider moid c ys t 7 . N eur ofibr oma 13 Common lesions
- 14. Click to edit Master title style 14 • Th e lin e o f a tta c h me n t o f inf med velum to Tela is Telovelar ju n c tio n , e xte n d fr o m n o d u le in to e a c h la te r a l r e c e s s . H ydr oc ephalus is one of the c onditions that c an r es ult fr om: • in A rnold C hiari malf ormat ion ( Typ e II C h ia r i malfor mation) a n d Oth e r ma s s e s • Me d u llo b la s to m , ar is es in the c er ebellum and c an ther efor e imp in g e o n th e r o o f o f th e fo u r th ve n tr ic le . 14 Clinical
- 15. Click to edit Master title style 1515 Clinical
- 16. Click to edit Master title style 16 Thank You
Editor's Notes
- #3: Hz section rhomboid, tent shaped, csf filled. The choroid plexus produces the majority of CSF, along with the ependymal cell layer of the ventricles and cells lining the subarachnoid space. CP are modified ependymal cells Situated in posterior cranial fossa. Infront of cerebellum behind upper part of mo and pons
- #5: The AICA was responsible for supplying the plexus near the cp angles, as well as a portion of the lateral recess of the fourth ventricle into the lateral apertures. The PICA supplied the choroid plexus in the median aperture and roof of the fourth ventricle.
- #7: Lat recess : left and right The lateral recess is a unique structure communicating between the ventricle and cistern, which is exposed when treating lesions involving the fourth ventricle and the brainstem with surgical approaches such as the transcerebellomedullary fissure approach In addition of a lateral recess incision to cerebellomedullary fissure dissection facilitates cerebellar hemisphere retraction. it was directed toward internal lesions of the fourth ventricle from the foramen of Magendie to avoid a vermis incision.
- #9: Sup : continue above with third ventricle with cerebral acueduct, present in midbrain Inf : continue below with cental canal of spinal cord Lateral angle : 2 in number, lies above inferior medullary velum and lateral to nodule
- #10: Floor in 3 parts : upper triangular, lower triangular, intermediate area. Gracile and cuneate are in mo
- #11: Gracile and cuneate are in mo
- #12: Superior collcululus : superior brachium and same for inf. Part of tectum of midbrain eye movements like pursuit and saccades Inf colliculus tectum : vestibule ocular response and specific amplitude modulation 1. Median sulcus 2. median eminence 3. sulcus limitans 4 vestibular area 3.5 superior fovea 3.6 locus ceruleus (NE) 3.7 inf fovea, 2.8 stria medullaris 2.9 facial colliculus 2.10 hypoglos tri 2,11 vagal tria 2.12 area postrrema ( vomit)
- #13: Upper slo[pe: formed by smv (thin sheet of white matter), sup cerebellar ped. Apex ext into white core of cerebell Lower slope formed by thin sheet of non neur tissue( Inf med vel). Vent and dorsal layer of pia form tela choroidea , lie b/w inf part of vermis and lower part of roof of 4th vent ,at tip lie nodule. Imv : formed by ventricular ependyma + pia choroid plexus : tuft of capillaries (br of pica)
- #14: Pediatric masses are more common. Ependymomas are the third most common pediatric brain tumors but only account for 1.9% of adult primary brain tumors. Mb account for 10% of pediatric tumor
- #15: In the past, access to lesions of the fourth ventricle was through the cerebellar cortex by opening the cerebellar vermis; this was called the transvermian approach. telovelar approach is gaining favor; this is performed by accessing the fourth ventricle through the cerebellomedullary fissure, a space. This functions as a natural track into the ventricular cavity