Brain Stem Class Notes

Brain Stem Medulla bilangata (in Melenaphaton). Pens (in Helentaphalon) Milbratacephalon). Medulla (lower part of brainstem) starts from the upper part of the spinal cord (but no and bourk but asusly its the first thing forming after exitat foramen magnum Also, the upper part of brainstem usually continues with the Ofencephalon •Its called the Brainstem because it is neccessary to be alle because if there is a lesion to the lower broin stem, the result is death, and lesion in upper brainstem will resull in a comma. •It is also neccessory because its the center of contred of cordionscular and respiratory systems. •Awareness, conclousness, Homeostasis, de all controlled in the Brain Sten Functions of Brainstem Homeostasis & conciousness •Passage & Afferont & Efferent fibers •Orlyin & Cranial Nerves Clinicallyel a patient has a paralysis of the body and bongue of the Some time, usually we guess that the lesion is in the Brain stem -If a patient has a body paralysis, or loss of sensation, and at the same time, a medial/lateral deviation & the eye, it can be guessed that the lesion is in the brain stem -If a patient has a problem with swallowing, the lesion would be in the Brain stem. foo All of these clinical guesses are because the Brainstem is -NILAIA the origin of all the CN'S Brainstem Has four surfaces: Anterior, pusla Anterior border In the Medulla Asalons with continuation of the Anteriomedian sulces Two anterolateral sulei continuing with the ansonstaterad sulard Se Between Mer sulol, them rexagonite gids wuppo The -In the Ankerdoteral sudd, exist's be origin of CNX Sparkassid nerve -Behind those two sutet, more towards posterior lateral, Bsist the emergence of three cronial nerves CN Glossophorungent n, Vagus os and Accesorry in respectively the macions & that comil metre sully angis of the che -Between the Medulla and pons, there is a horizontal sulcus called (Ponto medullar sulkus -Fortemedullar sulcuss the eggs of three cruftiol nerves on each side! CNAbducens n., Fabial n., Vestidocochlearn. respectively from medial Lo lateral side thin -Facial n. hos tue rats everying thick modor By sensory In the Pons! It is a wide area in the Brainstem. -There is a vertical sulcus on the medial side culled Basiler s because this is where the Basilar artery passes -Laterally in the Pons, Berge's the Trigeminal n.CNI, also with two the roots i thin motor and thick Sensory Between the forms and midbrain, exists a horizontal sulcus called Porhopeh Sulrs where two CN emerge: CNTE&CNN: Oculomotor & Trochlear netes -NILAI-respectively from babushitential medial to later In the Midbinin uppermest & Smallest port of the bandisten -Infandikuken & mammilary bodies are not porn di the midtenin but they appear hanging in that area -It has a serebral peduncle on auch side and betimon them there is a space ated interpedunculor fossa, -In this space there are many inholes catted gruply called Fosterior perforated substance for the passage of It's called a posterior perforated Substance because there are also other Anterior perforated substances. They're both on the anterior side, but the Anterior perforated Substance is a bit more anterior because the Brainstein is inclived. As known, the first and second CNs are parts of the Brain, Not the Brainstem, which means they are parts of the CNS, and hence, they are not peripheral. This is because around those two CNS, there are meninges. -Optic tracts cross above the two peduncles pand join in the ophic Chiasma which is the continuation of optic nerve (CNII) Starting from the eye. oplic track ques othe deep bensin back to the posterior port of the Thalamus Lateral view of Brainstem -In the Medulla, there is an oval shaped eminence called the -Lateral part of Plons has the middle cerebellar peduncle -Milbrain has the oate tract passing laterally Posterior vie In the pocherior side of the bombaster, Bits the cerebellum. Medulla -is dended into two parts i lover port and Alor part - -Liver part is the some as the sc. It has a sulcus in the middle called Poviromentul sidors, and to later) Suk alled Pobtoul suc -Groche e cureakis Fascicula in spinal cond home comme in the Brainstem is the Medalla as fascicular m then go up to the kaucies of concile & comahn habercles in the cloned pars of Proin them -Open parte of Brainstem is posterior behind the Medulla le pers which is the location of the 4th ventricle 4th ventricles hos 2 triangles: upper longle flower frangle -has a roof and floor, because the Brainstem is not writ positioned, it is a lille bit inclined ses we can not callll Anterior leposteriat instead of road for -roof of the 4th ventricle is conred by meninges (Pia matter J& un ependymal layer -It has three fommins, one infefor, and two literal -Medion foromen s called Magendie Foramen, and lateral forumina are called Lushka Fummins - Through these foramina, CSF passes into the Epidural space, covering the brain & Spinal and * If one of these fuormina is blocked, CSF will be trapped in the ventricles causing Hydrocephalia -CSF goes into the central through the 4th ventricl because control canal is the continuation of the way & ventricles. So sc is exterilly d'internally cover with CSF Posterior part of Milbemin: -There are four collicult two superior I tuo infartor -Superior calliciull are parts of the viewed system and Inferior Callicidi are parts of the auditory system Oragnof the Fecto spinal tract Strats from the Superior callbull of the midbrain Inferior to the Colliculi is the the Trochlew n (CANIT). The the only CN twal emerges posteriority in the Bratasem Pineal gland isn'tia port of the medbrain, but it hongs in that area, is part of the Diencephallon -3rd ventricle is a part & the Diencephallon asuell -Laterally there are medial & lateral Groniculate bodies on pch -Medial is for pathway flateral is for me bisual puthienng -There is a connection between Superior callicunt & lateral φανήμα -hal. Calliculi & medial genkidute since they both share the same pathway