sjldllds ;l;sf’;’;s بسم الله الرحمن الرحیم 1389 1 isfahan medical faculty,...

sjldllds

• ;l;sf’;’;s

بسم الله الرحمن الرحیم

1389 1Isfahan Medical Faculty, Anatomical Sciences Department

1389 Isfahan Medical Faculty, Anatomical Sciences Department

2


3Figure 12.2b

) ( فرمود ع صادق :امام

»روز – واقعى فضيلت مردم اگر قسم خدا بهىىىى ىىىى ىىىىىىى ىىى غدير«رامىشناختند،فرشتگانروزىدهبارىىىىى ىى ىىى

ىىىى بخششهاىىى ىىىى ىى و باآنانمصافحهمىكردندشناخته، را روز خدابهكسىكهآن

. نيست قابلشمارش


4Figure 12.2b

Brain Stem 8th Lecture

Clinical points of Brain stem


5


6

Review blood supply

• Vertebral• Basilar• Posterior cerebral• Anterior spinal• Posterior spinal• PICA• AICA• Superior cerebellar• Posterior communicating


7


8


9


10


11


12


13


14


15


16


17


18


19


20


21

C-P angle

• An space in posterior cranial fossa bordered by:

• 1- superipr petrosal crest

• 2- lateral pons, interiorly

• 3- cerebellum, posteriorly


22


23


24


25


26


27

Thank youThank you


28

Lesions of Brain Stem


29

Lesions of cerebral hemispheres


30

Projection of Cerebral Hemispheres to Brain stem & Spinal cord

• Contra lateral projection of cerebral hemispheres to spinal cord

• Bilateral projection of cerebral hemispheres to Brain stem except two points:– Genioglossus– Lower 1/3 of the face muscles


31


32


33


34


35

Facial pathway


36

Facial pathway


37


38


39


40

Right abducent Palsy


41

What is your Diagnosis?

•


42

Left oculomotor Palsy Left abducent Palsy


43

Hook & 3 pillars

CN 7 closes & CN III pens


44

Ptosis or Droping of the eyelid


45


46

Trochlear Palsy

• Produces elevation of eye; patients often bring down chin and tilt head away from affected eye to correct diplopia.

• TN is most commonly injured CN in head trauma; tumor, infection and aneurysm can also damage TN.


47

Trochlear Palsy


48


49


50


51


52


53


54


55

Thank YouThank YouThank YouThank You


56


57


58

Thank YouThank YouThank YouThank You

1389Isfahan Medical Faculty,

Anatomical Sciences Department 59


60


61

BRAIN STEM LESIONS Unilateral brain stem lesions (Fig. 19.21, Fig. 19.22) may arise as a result of extrinsic compression of the brain stem by space occupying tumours (e.g. meningioma, acoustic neuroma or metastatic carcinoma) or may be caused by intrinsic disease (e.g. glioma, demyelination or stroke). The clinical syndrome is determined by the neuroanatomical site of the lesion.


62

At the segmental level, an ipsilateral cranial nerve palsy occurs. Below the level of the lesion, there is a contralateral loss of power and sensation in the limbs (corresponding to dysfunction of the decussating corticospinal and ascending sensory pathways), and ipsilateral incoordination of the limbs (as a result of the interruption of efferent and afferent cerebellar connections).

1389

Isfahan Medical Faculty, Anatomical Sciences Department

63

The ipsilateral cranial nerve dysfunction reflects the segmental level of the lesion in the midbrain, pons and medulla. Midbrain lesions cause ophthalmoplegia, pupillary dilatation and ptosis (oculomotor nerve palsy) and impaired upward gaze (e.g. due to a pinealoma). Pontine lesions (e.g. an acoustic neuroma in the cerebellopontine angle) lead to ophthalmoplegia (abducens nerve lesion), loss of facial sensation and weakness of masticatory muscles (trigeminal nerve lesion), weakness of facial muscles (facial nerve lesion), deafness and vertigo (vestibulocochlear nerve lesion). Medullary lesions cause a ‘bulbar palsy', i.e. dysarthria, dysphagia and dysphonia, with wasting of the hemi-tongue and palate (glossopharyngeal, vagal and hypoglossal nerve lesions) and weakness and wasting of sternocleidomastoid and trapezius (accessory nerve lesion).In addition to this focal brain stem syndrome, blockage of the outflow of CSF from the fourth ventricle via the foramina of Magendie and Luschka (e.g. by extrinsic tumours) produces hydrocephalus, which is characterized by headache, papilloedema and progressive stupor and coma.


64

Bilateral destructive lesions of the brain stem are fatal if untreated, because of damage to ‘centres’ in the medulla that control respiration, heart rate and blood pressure. Impairment of the reticular activating system in the core of the brain stem leads to progressive impairment of consciousness, followed by stupor and coma. In this state of ‘brain stem death', life can only be supported artificially. This is the fate of all untreated expanding space-occupying lesions in the cranium (e.g. haematoma, abscess, tumour, whether extrinsic or intrinsic to the brain, and cerebral oedema). A space-occupying lesion within the unyielding skull raises the intracranial pressure directly and also indirectly by obstruction of CSF flow, which causes headache and papilloedema


65

The brain is distorted and displaced downward (rostro-caudally) within the skull and meningeal framework. The brain stem is vulnerable to compression at two critical sites, which are determined by the neuroanatomical relationship of the meningeal tentorium and foramen magnum to the cerebral hemisphere (supratentorial) and brain stem (infratentorial).


66

The downward displacement of the cerebral hemisphere leads to herniation of the ipsilateral medial temporal lobe (uncus) through the tentorial notch. There may be direct ipsilateral compression of the midbrain and emergent oculomotor and trochlear cranial nerves or contralateral compression of the upper brain stem by the abutting sharp edge of the tentorium. The ipsilateral posterior cerebral artery is vulnerable to compression at this site. Unilateral herniation is heralded by a progressive oculomotor nerve palsy (ophthalmoplegia, pupillary dilatation and ptosis), contralateral limb weakness, falling


67

• انسانها از که چیزی اولین پنج نمازهای شود، می سؤال

است گانه

• كند رفتار چنان مردم با كه هرآنگونه او با آنها دارد دوست كه

است عادل كنند، رفتار

• كه . آنگونه را، خدا كه هركند، بندگى اوست، سزاوارو ازآرزوها بیش خداوند

كند مى عطا او به كفایتش

• و باشید معتدل دنیا طلب دركس هر به زیرا ، نزنید حرص

رسد می اوست قسمت چه هر

• این . در خداوند را چیز دوو : ، تعدی میدهد كیفر جهان

مادر و پدر ناسپاسی• باکی مردی که دیدید هرگاه

چه و گوید می چه که نداردمی گفته اش دربارهشریک کسی شود،چنین

است . شیطان

sjldllds ;l;sf’;’;s بسم الله الرحمن الرحیم 1389 1 isfahan medical faculty,...

Documents