Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

mrcs - General > Neurosurgery > Flashcards

Neurosurgery Flashcards

1
Q

Ventricular system

A

Paired lateral ventricles
Communicate by foramin of Munro with third ventricle

Third ventircle communicates via the aqueduct to the foruth ventricle

Outflow foramina: Luschka, and Magendie connect with basal and subarachnoid spaces

Large CSF cisterns around the base of the brain (e.g. cisterna magna, cerebellopontine cistern).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Anterior cerebrlal artery supplies

A

Frontal lobe and medial parts of parietal lobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Middle cerebral artery supplies

A

Posterior frontal region and most of temporal and parietal regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Posterior circulation supplies

A

Brain stem
Cerebellum
Occipital lobes
Inferior part of temporal lobes

End-arteries –> well defined stroke syndromes

Paired vertebral arteries –> basilar artery –> paired posterior cerebral arteries

Posterior cerebral arteries communicate with the anterior circulation through the posterior communicating arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In a normal supine adult, ICP is the same as the CSF pressure

A

Opening pressure of LP = ICP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cerebral perfusion pressure (CPP)

A

= MAP - ICP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why do you get a brady with raised ICP?

A

Rising ICP

Cerebral perfusion pressure = MAP - ICP

To achieve CPP, MAP increases as ICP increases

Increased MAP –> reflex bradycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Cerebral perfusion pressure (CPP)

A

= MAP - ICP

CPP of > 60 mmHg is generally required to sustain adequate cerebral perfusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sub-falcine herniation (cingulate gyral)

A

Caused by para-sagittal mass

Ipsilateral cingulate gyrus may herniate beneath the free edge of the falx

Anterior cerebral artery may be compressed leading to hemispheric infarction
Otherwise, reduced GCS is only clinical sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Tentorial herniation

A

Large ipsilateral lesion

Medial part of temporal lobe is pushed down through tentorial notch –> becomes wedged between tentorial edge and midbrain

Cerebral peduncle is pushed against sharp tenrotial edge

Midbrain and uncus become wedges at tentorium

Aqueduct is compressed , obstructing CSF flow

Obstruced venous flow –> midbrain haemorrhage

Uncul herniation:

  • Falling GCS
  • Motor component of GCS becomes asymmetrical
  • Ipsilateral 3rd nerve palsy, dilated an ddixed pupil
  • Hypertension and bradycardia
  • Respiratory arrest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Tentorial (uncal) herniation

A

Large ipsilateral lesion

Medial part of temporal lobe is pushed down through tentorial notch –> becomes wedged between tentorial edge and midbrain

Cerebral peduncle is pushed against sharp tenrotial edge

Midbrain and uncus become wedges at tentorium

Aqueduct is compressed , obstructing CSF flow

Obstruced venous flow –> midbrain haemorrhage

Uncul herniation:

  • Falling GCS
  • Motor component of GCS becomes asymmetrical
  • Ipsilateral 3rd nerve palsy, dilated an ddixed pupil
  • Hypertension and bradycardia
  • Respiratory arrest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Foraminal (tonsillar) herniation

A

Lesion in posterior fossa

Causes cerebellar tonsills and midbrain to be pushed down through foramen magnum

Cerebellar impaction –> medulla compression

Clinical features:

  • Rapid reduction in GCS
  • Acute hypertension
  • Bilateral extensor responses
  • Bilateral fixed and dilated pupils
  • Respiratory arrest

(Can be caused by LP in raised ICP –> coning)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Berri aneurysms

A

85% in anterior circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Nimodipine

A

Medical management of SAH

Alonside maintaining CCP and haemodilution

Avoid hypotension and fever - associated with poorer outcome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Amyloid angiopathy

A

Common cause of intracerebral bleed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Coma

A

Defined as GCS of 8 or less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Indications for haematoma evacuation

A

> 5mm midline shift

Significant impairment of GCS

Protracted headache or vomiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Intracranial haematoma risk pattern

A

No skull fracrure, GCS 15 –> 1 in 6,000

Skull fracture, GCS 15 –> 1 in 30

GCS 14 or less –> 1 in 4

19
Q

Cervical spinal trauma

A

Commonly subluxation C5 on C6

20
Q

Glioblastoma

A

Grade IV

21
Q

Gliosarcomas

A

Grade IV

22
Q

Anaplastic astrocytoma

A

Grade III

23
Q

Anaplastic oligodendroglioma

A

Grade III

24
Q

Astrocytoma

A

Grade II

25
Q

Oligodendroglioma

A

Grade II

26
Q

Ependymoma

A

Grade II

27
Q

Pilocystic astrocytoma

A

Grade I

28
Q

Dysembroplastic neuroepithelial tumour

A

Grade I

29
Q

Ganglioma

A

Grade I

30
Q

Shwannomas

A

Cranial nerve tumour

Nearly all affect the vestibulocochlear nerve

Grows and expands within internal auditory meatus

Cranial nerve VII and VIII become compressed as it grows into cerebellopontine angle

Early VIII th nerve symptoms:

  • Progress deafness
  • Tinnitus
  • Vertigo

Larger tumours may involve the trigeminal nerve, eading to diminished facial sensation, as well as the pons and cerebellum, leading to ataxia and nystagmus.

Compression of fourth ventricle –> hydrocephalus

31
Q

Prostate cancer metastasis

A

Commonly mets to cranium itself

NOT brain parenchyma

32
Q

Galidium contrast doesn’t cross BBB so…

A

In areas of pathology there is breakdown of the BBB
–> uptake by tumours

Meningiomas are mesodermal in origin hence don’t have BBB —> they will take up contrast depist being only Grade I

33
Q

Brain Primary

A

Primary cerebral tumours arise from:

supporting cells of the brain (gliomas)

from the walls of ventricles (ependymomas)

from the roof of the fourth ventricle (medulloblastomas).

34
Q

Brain Primary

A

Primary cerebral tumours arise:

Supporting cells of the brain (gliomas)

Walls of ventricles (ependymomas)

Roof of the fourth ventricle (medulloblastomas).

35
Q

Paediatric primary brain tumours

A

Age <2: Teratomas, Astrocytomas, PTENs
Occur anywhere

Age 2 - 15:
Usually PTENs (primitive neuroectodermal tumours) (also known as medulloblastomas when in posterior fossa), astrocytomas and ependymomas
Most common site is posterior fossa

36
Q

Management of paediatric brain tumours

A

Surgery alone is not curative in High Grade tumours

Combination of surgery, chemotherapy and radiotherapy used

Radiotherapy not suitable for children under 3 –> damages developing brain
Age 3- 8: Radiotherapy may cause loss of IQ and other neurodevelopmental delays

37
Q

Open spinal dysraphism

A

Spina bifida aperta
Myelomenigocoele

Open spinal defect with LMN signs, weakness and numbness below lesion and a neuropathic badder

Often develop hydrocephalus post closure and require a ventriculoperitoneal shunt

90% have malformation of hindbrain: Chiari II –> respiratory and feeding difficulties

Also develop scoliosis

38
Q

Closed spinal dysraphism

A

Spina bifida occulta
Encompasses lesions: Lipomyelomeningoceole, meningoceole, tight filum terminale syndrome, sinus tract and intradural dermoids, split cord malformations and cuadal agenesis

Often asymptomatic

Later neurological deterioration or bladder dysfunction are due to tethering of the developing cord at the lesion site
Mx: surgical untethering

Individuals do not develop hydrocephalus and
there is no association with the Chiari malformation

39
Q

Causes of hydrocephalus

A

Osbtruction - non-communication

  • Congenital: aqueduct stenosis
  • Tumour
  • Arachnoid adhesions or fibrosis secondary to intraventricular haemorrhage or SAH

Communicationg / external

  • Ventricular system is patent
  • There is reduced flow through basal cisterns or absrobtion of CSF by arachnoid granulations
  • -> commonly due to fibrosis post meningitis, SAH, or sagittal sinus thrombosis

Over-production
-Choroid plexus papilloma

40
Q

Gait ataxia, Incontinence and Cognitive decline

A

Normal pressure hydrocephalus

41
Q

Craniosynostosis

A

Premature closure of / absence of cranial suture

Premature fusion of sagittal suture: Scaphocephaly
Premature fusion of coronal suture: Plagiocephaly

42
Q

Dermal sinuses

A

Squamous epithelium communicate with intracranial cavity

Mostly occipital region
Associated with inclusion dermoids

43
Q

Complications of chronic disc herniation

A

Nerve root compression: lateral recess stenosis

Cord compression: Spondylitic myelopathy

Cauda equina: Lumbar canal stenosis

Pain along root of compression and diminished sensation in roots below

44
Q

Mx of disc prolapse

A

If mild causing radiculopathy: conservative +/- delayed micropdiscectomy at 6 weeks

If posterior rupture into canal: urgent removal and plating

mrcs - General (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions