(6) Neurosurgery Flashcards
What is neurosurgery?
Surgery performed on the brain or the spinal cord usually for brain and spine tumours, congenital spine defects and vascular lesions
What is a subarachnoid (SA) haemhorrage?
Bleeding into the SA usually from ruptured aneurysm at or near the Circle of Willis
What lies in the SA space?
Intracranial vessels that give off small perforating branches to the brain tissue
What happens when there is in intercranial aneurysm rupture?
Causes intracerebral bleeding with or without a subarachnoid haemorrhage
What is an aneurysm?
Localised blood filled dilation of a blood vessel caused by a disease or weakening of vessel wall
What causes an aneurysm?
Stretching and thinning of the artery wall over time
What are the two forms of aneurysms?
- Saccular which is a single bulge on one side
- Fusiform which is a bulge in the middle of the vessel
What are the common sites for aneurysms?
- 85% vessels from the Circle of Willis
- 20-25% MCA
- 35-40% ACA
- 30% internal carotid
- 10% posterior circulation
What is the most common type of subarachnoid haemorrhage aneurysm?
Berry aneurysm (balloon like structure in vessel)
What are risk factors for SAH?
- Age (most common 40-60)
- F:M (3:2)
- Hypertension
- Family history
- Smoking
- Cocaine use
- Alcohol abuse
What are clinical feature of SAH (7)?
- Severe, unrelenting headache (thunderclap)
- Vomiting
- Neck stiffness
- Seizure
- Lethargy
- Limb weakness
- Associated trauma
What are the symptoms and signs of SAH (9)?
- Headache
- Transient or prolonged loss consciousness
- epileptic seizure?
- +/- nausea & vomiting
- signs of meningism
- Focal damage
- papilloedema
- Reactive hypertension
- Pyrexia
How is a SAH investigated?
- CT most common diagnosis
- MRI not routinely used but helps identify multiple aneurysms
- Lumbar puncture (CSF)
- Angiography
How is a cerebral aneurysm treated?
Surgical treatment
- direct clipping
- balloon embolisation
- wrapping
May be ventilated similar to TBI
What is a complication of SAH?
Cerebral Vasospasm
What is cerebral vasospasm?
a delayed narrowing of large arteries at the base of the brain after a SAH
When does a cerebral vasospasm usually occur?
- Typical 3-5 days after haemorrhage
- Maximal narrowing at 5-14 days
What is the treatment for cerebral vasospasm (6)?
- Triple H Therapy
- keep blood vessels open by increasing the amount of blood to the brain
- keeping BP up
- hydration
- if untreated can lead to cerebral infarcation
What is Triple H Therapy?
- Hypertension
- Increase cardiac output & control BP - Hypervolemia
- intravenous fluids - Haemodilution
What are other complication associated with SAH?
- Rebleeding
- Hydrocephalus
- Hyponatremia
- Seizures
- Tentorial herniation
What is rebleeding?
- major problem following aneurysm SAH
- 28 days, 30% rebleed & 70% of those die
What is hydrocephalus?
It is an abnormal build up of fluid in the fluid containing cavities in the brain
How does hydrocephalus occur?
- Excessive accumulation of CSF results in widening of spaces in the brain (ventricles)
- Widening creates potentially harmful pressure on the tissues in brain (increase ICP)
When does hydrocephalus occur in patients with SAH?
- Acute occurs within 72 hours in ~20% due to CSF obstruction
- Further 10% it can develop late
What is the management for an aneurysm?
- clipping via craniotomy used to be used
- coiling new technique
- has less complications & greater survival
What does wrapping involve?
- if the width of the aneurysm neck prevents clipping, the muslin gauze may be wrapped around fundus
- increased risk of haemorrhage
What does coiling involve?
insertion of platinum coil into the blood vessels through small incision under X ray guidance
What is involved in physiotherapy during the acute phase of SAH?
- check angiogram results
- untreated aneurysm = FLAT BED REST
- treated aneurysm = risk developing vasospasm
- when stable physio treatment dependent on presenting problems
What is Arteriovenous Malformation (AVM)?
- leading cause of stroke in young people
- developmental anomalies in the intracranial vasculature (not neoplastic)
- “Tangled” blood vessels
- capillaries are missing meaning arteries directly connected veins
- most common in MCA
- usually superficial but can be deep
What is the clinical presentation of AVM?
- well-localised headache unilateral & throbbing
- +/- nausea & vomiting
- cranial nerve involvement?
- seizures
- hemiparesis
- cognitive, language etc
How are AVMs investigated?
- MRI
- Angiogram
- CT scan
What is the treatment for AVMs?
- Goal to diminish amount of blood flowing to AVM
- Excision (most effective)
- Embolization of feeding vessels
- May use stereotactic frame
- If not treated AVMs will enlarge
What is the stereotactic technique?
- Enables accurate placement cannula or electrode in predetermined target
- CT & MRI compatible
- head ring attached to skull and rods inserted
- rods removed and probe inserted using CT
What is a brain tumour?
- Growth from different brain cells such as astrocytes, glial cells, lining of ventricles and meninges
- Benign or Malignant
- Secondary metastases
When is stereotactic surgery used?
- Lesions in thalamic nuclei for tremor
- lesions globus pallidus
- electrical stimulation movement disorders
- aspiration of cyst
- biopsy for deep tumours
- irradiation of small, deep rooted AVMs
What are the most common sites of tumours in adults?
- Cerebral 80-85%
- Cerebellar 15-20 %
What are the most common sites of tumours in children?
- Cerebral 40%
- Cerebellar 60%
How are brain tumours classified?
- cell type it originates
- location it originates
What are the pathological classifications of brain tumours?
- Gliomas from glial cells
- Meningiomas from meninges
- Haemangioblastoma from blood vessels
- Neuroma from nerve sheets
- Pituitary adenoma
What are the most common types of brain tumours?
- Glioblastoma Multiformes (GBMs) most primary (12-15%)
- Meningiomas most common benign
- 67% brain tumours are gliomas
What are the grading of Gliomas?
G1 - pilocytic astrocytoma
G2 - diffuse astrocytoma
G3 - Anaplastic astrocytoma
G4 - Glioblastomas
What are Glioblastoma Multiforme (GBM) tumours?
- most common and aggressive tumour
- M:F 3:2
- frontal, parietal, temporal, and thalamic regions
What causes GBM?
- unknown
- genetic abnormalities found
What are the symptoms of GBM?
- Headaches
- Seizures
- Changes in mental status
- Personality changes and memory loss
- vomiting
- reduced consciousness
How are GBM’s investigated?
- MRI
- CT scans
What is the treatment of GBM?
- Surgery (partial debulking)
- Radiotherapy
- Stereotactic irradiation
- Chemotherapy
What are the complications of surgery for GBM?
- infection
- bleeding
- oedema
- damage normal tissue
What are the complications of radiography for GBM?
- oedema
- demyelination
- radionecrosis
What are the complications of chemotherapy for GBM?
- Toxicity
- bone marrow suppression
What is the mortality for high grade gliomas?
- depends on tumour location, progression, and pressure
- many won’t survive >3 years
Where do meningiomas occur?
Intracranially at the base of the skull close to venous sinuses
What are the complications for brain surgery?
- brain damage (primary or secondary)
- cerebral oedema
- CSF leak
- Thrombosis or haemorrhage
- DVT
- Epilepsy
- Infection
What should be done on objective assessment with a patient?
- motor
- sensory
- cognitive
- speech
- cranial nerves
- balance and mobility
- functional activity
What is involved in physiotherapy for neurosurgery?
- similar to head injury
- depends on site and severity
- MDT approach
- Family involvement
- Discharge plan
