Neuro Block Iii - I

Front 1

Name the boundaries of the interpeduncular fossa?

Back 1

Anteriorly - Optic chiasma
Posteriorly - superior border of pons
Anterolaterally – Optic tracts
Posterolaterally – crus cerebri

Front 2

What are the structures that lie in the floor of the interpeduncular fossa?

Back 2

Tuber cinereum with infundibulum
Mamillary bodies
Posterior perforated substance
“Interpeduncular cistern” a dilated subarachnoid space lies in it and it contains the“circulus arteriosus”

Front 3

What are the structures that cross the crus cerebri?

Back 3

What are the structures that cross the crus cerebri?
Optic tract
Basal vein
Posterior cerebral artery
Trochlear nerve

Front 4

Name the cranial nerve that emerges through the medial border of the crus cerebri?

Back 4

Oculomotor Nerve III

Front 5

Name the cranial nerve that emerges on the dorsal aspect of the brainstem?

Back 5

Trochlear Nerve IV

Front 6

What is tectum and how many colliculi that it contains?

Back 6

It is made up of two pairs of colliculi (quadrigeminal bodies)
A Pair of superior colliculi
A pair of inferior colliculi.

Tectum = Roof

Front 7

What is the function of superior colliculus?

Back 7

Superior colliculi are stations of visual reflexes

Front 8

What is the function of inferior colliculus?

Back 8

Inferior colliculi are part of the auditory pathway

Front 9

Which tunnel lies within the midbrain?

Back 9

Cerebral aqueduct.

Front 10

What is the name of the grey matter surrounding the cerebral aqueduct? What is its functional importance?

Back 10

Periaqueductal Gray matter. It surrounds the aqueduct and is important in modulation of pain.

Front 11

What happens when cerebral aqueduct is blocked?

Back 11

Hydrocephalus

Front 12

What are the three parts of the cerebral peduncle?

Back 12

Tegmentum, Crus Cerebri, Substantia nigra.

Front 13

What are the tracts that lie in the crus cerebri?

Back 13

Motor tracts

Front 14

What are the lemnisci that lie at the level of inferior colliculus?

Back 14

Medial lemniscus – contains contralateral fibers of three sensations (conscious proprioception, vibration and two point discrimination)
Trigeminothalamic tract – Pain and temperature of contralateral half of the face
Spinothalamic tract – carries pain and temperature of the opposite half of the body
Lateral lemniscus – carries predominantly contralateral hearing fibers

Front 15

What are the lemnisci that lie at the level of superior colliculus?

Back 15

Everything except lateral lemniscus

Front 16

At which level the red nucleus is present?

Back 16

Level of the superior colliculus

Front 17

What type of neurons is present in the substantia nigra?

Back 17

Dopaminergic

Front 18

What happens when substantia nigra is degenerated bilaterally?

Back 18

Parkinsonism

Front 19

Where do you locate the nuclei of oculomotor nerve?

Back 19

Level of superior colliculus of midbrain.

Front 20

Where do you locate the nucleus of trochlear nerve?

Back 20

Trochlear nerve nucleus lies in the floor of the cerebral aqueduct of the midbrain at the level of inferior colliculus

Front 21

What are the four signs of oculomotor involvement?

Back 21

ophthalmoplegia on the same side. Fixed and dilated pupil on the same side.

Front 22

What is the sign of trochlear involvement?

Back 22

Nucleus - opposite side paralysis of superior oblique since the trochlear nerve crosses. Trochlear nerve – same side superior oblique muscle

Front 23

What are the two structures involved in the medial midbrain syndrome?

Back 23

Webers syndrome = Medial midbrain syndrome. Crus Cerebri and Oculomotor nerve

Front 24

What are the two structures involved in the Benedikt’s syndrome?

Back 24

It involves oculomotor nerve and red nucleus.

Front 25

What is parinaud’s disease or syndrome? What is characteristically lost in this syndrome?

Back 25

Most common cause is pineal tumor which compresses the superior colliculus and Pretectal area. The vertical gaze is lost.

Front 26

What happens when the left crus cerbri is cut?

Back 26

Right Spastic paralysis. (Contralateral)

Front 27

What happens when the right crus cerebri is cut?

Back 27

Left Spastic Paralysis (Contralateral)

Front 28

What happens when the right medial lemniscus is cut?

Back 28

Contralateral (LEFT side) loss of conscious proprioception, vibration and two point discrimination

Front 29

What happens when the left medial lemniscus is cut?

Back 29

Contralateral (RIGHT side) loss of conscious proprioception, vibration and two point discrimination

Front 30

What happens when the right trigeminolemniscal tract is cut?

Back 30

Contralateral (LEFT side) loss of pain and temperature of face

Front 31

What happens when the left spinal lemniscus is cut?

Back 31

Contralateral (RIGHT side) loss of pain and temperature of the body

Front 32

What happens when the lateral lemniscus is cut?

Back 32

diminished hearing but not complete loss because auditory fibers are represented bilaterally

Front 33

Where does lateral lemniscus terminate?

Back 33

Inferior colliculus of Midbrain.

Front 34

In which cranial fossa the cerebellum is located?

Back 34

Posterior cranial fossa

Front 35

What roofs the cerebellum?

Back 35

Occipital bone

Front 36

Which structure lies in the roof of the fourth ventricle?

Back 36

Cerebellum

Front 37

What are the three structures included under the hind brain?

Back 37

Two cerebellar hemispheres and a median vermis

Front 38

What are the three parts of the cerebellum?

Back 38

i) vermis and floculonodular lobes
ii) intermediate part (paravermal)
iii) lateral part)

Front 39

What is the name of the most anterior part of the vermis of the cerebellum?

Back 39

Anterior lobe

Front 40

What is the name of the most posterior part of the vermis of the cerebellum?

Back 40

Posterior or middle lobe

Front 41

Name the three peduncles of the cerebellum and what do they interconnect?

Back 41

Superior - Connects midbrain with cerebellum, Middle - It connects the pons with the cerebellum and Inferior - It connects the medulla oblongata with the cerebellum

Front 42

What are the three functional zones of the cerebellum?

Back 42

i) vermis and floculonodular lobes
ii) intermediate part (paravermal)
iii) lateral part

Front 43

What is the nucleus of the vermal zone of the cerebellum?

Back 43

Fastigial

Front 44

What is the nucleus of the paravermal zone of the cerebellum?

Back 44

Emboliform

Front 45

What is the nucleus of the lateral zone of the cerebellum?

Back 45

Dentate