Flashcards in Neuro-oncology Deck (136):
What is the evidence for extent of resection in GBM?
Level 2 evidence that those with complete resection have longer survival (Pichimerie et al ALA study patients)
What was the outcome of the Pichmeier et al study?
Patients with worse KPA and older have increased life expectancy with extent of surgical resection
What is the standard of care for GBM?
Stupp et al 2005 showed RT + concomitant temozolamide have better progression free and overall survival
What does MGMT methylation signify?
What is the evidence for operating on recurrent GBM?
Multiple small retrospective studies have shown a small improvement in survival with repeat surgery and extent of resection
What is a secondary line agent after Temezolamide for GBM?
Avastin (Bevacizumab) - approved for use with recurrent GBM as it improves progression free survival (not overall survival) compared to historical controls
What is a potential problem with Avastin (bevacizumab)
Disease may progress but the avastin prevents contrast enhancement so cannot see it on imaging
Would you give chemo/radiotherapy following resection of LGG?
If 40 y and/or subtotal resection had better progression free survival with chemoradiotherapy.
What is the role of TERT promoter mutations?
TERT mutation alone gives worst prognosis but TERT mutation with IDH-1 +/- 1p19q mutation gives the best prognosis!
What is the earliest mutation to occur in LGG?
What extra investigations can be performed prior to oncology surgery?
fMRI, intraoperative guidance, awake craniotomy, DTI for white matter tracts and angiography
What is the differential diagnosis of a durally based lesion?
Meningioma, haemangiopericytoma, lymphoma, metastasis, primary bone tumour and inflammatory lesions
What is the evidence for adjuvant therapy following surgery for a single metastasis?
SRS alone favoured survival and not giving WBRT prevents neurocognitive decline especially if
What is the differential diagnosis of a 4th ventricular lesion in a child?
Ependymoma / subependymoma
What is the management of a patient with a 4th ventricular lesion causing hydrocephalus?
Gross total resection of the lesion
Which foramen does the teloveoltonsillar approach open?
Foramen of magendie between the tonsil and the uvula
What is the disadvantage of a transvermian approach?
Should residual medulloblastoma be resected from the floor of the 4th ventricle?
No - chemoradiotherapy can be given to the residual
What is SUNCT?
Short lasting unilateral neuralgiform headache with conjunctival tearing
What does the spectroscopy for radionecrosis look like?
Flat line - lactate can be raised
AIDs, non-enhancing lesion with high flair signal - diagnosis?
PML - once treated with steroids will result in IRIS and start to enhance
What does the eccentric target sign in a ring enhancing lesion suggest?
What is the diagnosis of a T2 hypointensity with peripheral contrast enhancement and no restriction on DWI?
Granulomatous lesion - TB or sarcoid
Small cystic lesion with a vessel running through. Diagnosis?
Virchow Robin Cyst! (Dilated CSF space)
What should you think about in a patient with multiple VR lesions
Muchopolysacharidosis (Hurlers) and cryptococcus (if HIV)
What is TORCH?
Congenital infections that cause abnormalities:
Toxo, Rubella, CMV and Herpes encephalitis
What are the goals of surgery?
+/- seizure elimination
How are the white matter tracts classfied?
Association (short and long same side)
Projection (cranial to spinal)
Commissural (different side)
What are U fibres
Short adjacent association fibres between gyri
What are the components of the superior long fasciculus?
Arcuate fasciculus connects brocas and wernickes areas
What white matter tract runs to the post-central gyus?
What sulcus seperates the insula into anterior and posteiror portions?
Central sulcus of the insula
What is the role of the extreme capsule?
White matter U association fibres of the insula
Where do the insular perforators arise from?
What forms the corona radiata?
Both internal and external capsule fibres
Which arteries are found at the limen insula?
The lenticulostriate perforators
What forms the roof of the ventricular atrium?
Why are anterior cingulotomy performed?
Chronic refractory depression / OCD and Chronic pain
What are the projections of the medial and lateral olfactory gyri?
Medial to cingulate and lateral to amygdala
Where is the collateral sulcus?
Between the parahippocampal and fusiform gyri
Where is the diagonal band of Broca?
White matter fibre tract from the amygdala running to the anterior perforated substance
What histology marker suggests meningioma?
EMA (Epithelial membrane antigen)
What is the histology of a meningioma?
What is a new change in the WHO 2016 tumour classification for meningioma>
Brain invasive alone makes it grade 2
What is the grade of haemangiopericytoma?
WHO 2 (Solitory fibrous tumour = 1 and anaplastic = 3)
Synaptophysin positive tumour with oligodendrocyte-like cells?
What is the grade of SEGA?
What the histological features of a colloid cyst?
Arises from the anterior roof of the 3rd ventricle
Pineal region with rosettes?
Pituitary lesion with microcysts and Rosenthal fibres?
What is the difference between adamantinomatous and papillary craniopharyngioma?
Ada = 90% of all cranio's. Mainly in paediatric. Mutations in beta-catenin
Pap = 10% of all cranio's. Adults. BRAF mutation can be stained for!
What is the normal role of IDH-1?
Converts isocitrate to a-ketoglutarate
What is the function of mutated IDH-1?
What is the main IDH-1 mutation?
What is the prognostic benefit of IDH mutation?
In GBM survival is better with mutant IDH-1
What mutation is associated with astrocytoma?
What is ATRX?
Chromatin regulator. A loss of function mutation occurs in astrocytomas. The absence of ATRX in the nucleus suggests astrocytoma! Blood cells act as an internal control.
What does wild type mean?
What are the features of oligodendroglioma?
Fried egg appearance with staghorn vascularisation
Tumour has no IDH1, no 1p19q and TERT promoter mutation. What is the grade?
What is the diagnosis of a GBM which is Vimentin positive?
What are the histological features of a pilocytic astrocytoma?
Elongated hair like astrocytes with rosenthal fibres
What is the histological difference between schwannoma and neurofibroma?
Neurofibroma has the nerve fascicles running through the tumour whilst schwannoma is eccentric from the nerve.
What is the differential of an esthesioneuroblastoma?
Sinonasal undifferentiated tumour (SUNT)
Olfactory groove meningioma
What abscess occurs in AIDS patients in the basal ganglia?
Toxoplasmosis! With eccentric target sign means there is a nodule at the edge of the ring enhancement
How can you differentiate radiation necrosis from tumour?
What does incomplete ring enhancement suggest?
Demyelination (open ring is towards the ventricle)
What radiological sign do you see with large aneurysms?
Phase encoding pulsation artefact
What is IRIS?
Immune reconstitution inflammation syndrome - when the immune system response is over exaggerated after starting treatment
Which demyelination syndrome occurs in a monophasic pattern?
ADEM - all lesions are of the same age so all enhance! May have recent viral infection.
What organism causes a fungal mucocoele?
What T2 feature suggest TB abscess?
Dark on T2!
What are the causes of a miliary patter of lesions in the brain?
What are neuroglial cysts?
What are choroidal fissure cysts?
What are the locations for Virchow-Robin spaces?
Posterior perforated substance
Anterior temporal lobe (can have flair signal)
What condition should you think of in a patient with large VR spaces?
What do you think of in a HIV patient with dilated VR spaces?
Posterior fossa proteinaceous cyst without restriction?
What is TORCH?
Congenital infections that cause calcification within the walls of the ventricle:
What is a sign of chronic venous congestion with DAVF?
What is the most common tumour of the cavernous sinus?
Which nerve courses through the pterygopalatine fossa?
V2 (Maxillary branch) goes through for. rotundum to the pterygopalatine fossa
Where does V3 go?
Through the for. ovale to the Infratemporal fossa
What are the treatments for cavernous sinus meningiomas?
Symptomatic in young patient = debulk to decompress nerves and then SRS for residual
Non-symptomatic = conservative or SRS
What grading system is used for encasement of the carotid artery with meningiomas?
What is the name given to a hyperostotic meningioma of the lateral orbital wall?
What is a safe entry zone to the brainstem?
Areas with sparse brainstem nuceli or tracts
Should you resect a DVA with the cavernoma?
No, this is draining normal brain!
How do you manage carotid cave aneurysms?
How do you manage opthalmic artery aneurysms?
What factors affect coil vs clipping?
Which AComs are easier to coil?
What are the aneurysm configuration factors that need to be considered?
Pointing of aneurysm
Perforators / branches
Neck to dome ASPECT ratio
Bifurcation vs side wall aneurysm
What is the impact of angulation on coiling outcome?
Angles >90 deg have a higher chance of recurrance
What are the factors at angiography that suggest a false aneurysm?
Delayed inflow and outflow of contrast
Should you coil a false aneurysm?
NO! It will rupture
How do neck calcifications effect clipping?
If they are in the plane of the clip then it will prevent the clip from closing
When should you do a prophylactic EVD in a patient having endovascular treatment?
When there is blood in the 4th ventricle and they are having a stent (as this will need dual antiplatelet agents)
Does opening the lamina terminalis prevent hydrocephalus in SAH?
Yes, reduces risk from 14 to 4%
What are the endovascular types of angioplasty
What factors suggest which aneurysm has ruptured when there are mutliple ones?
Shape (round vs elongated)
Why should Marfans / FMD patients not be coiled?
The catheters can cause dissections on the way up
Should large partially thrombosed aneurysms be coiled?
No, surgery or flow diverter is needed
How do you manage false aneurysms?
Parent vessel occlusion or coil the part that is before the false aneurysm
What is the prevalence of aneurysms?
In a population of 100,000 how many aneurysms ruputure?
ISUIA trial rupture risks per 5 years?
Size: <7, 7-12, 13-24 and >25
Ant circ: 0, 2.6, 14, 40
Post circ: 2.5, 14, 18.4, 50
How is risk of aneurysm rupture calculated?
= 1 - (Risk of rupture per year x Life expectancy)
What factors are part of the PHASES score?
Size of aneurysm
Site of aneurysm
What are the non-surgical treatments of craniopharyngioma?
Gamma knife to the solid component
Cyst - ommaya reservior for aspiration
Bleomycin injection into the cyst
Lesions of the 3rd ventricle?
What factors should you consider when approaching a ventricular lesion?
Hemispheric dominance if transcortical
What are the approaches to the lateral ventricle?
Temporal (lateral or subtemporal)
What is the circulating volume of a child?
80 ml / kg
What is the surface marking for transcortical approach to the lateral ventricle?
MFG = 1 cm precoronal, 3.5cm lateral to the midline
What are the features of a colloid cyst on CT?
What are the causes of an intracranial cyst?
Developmental - neurenteric / arachnoid / porencephalic cyst
Neoplastic - benign / malignant / subependymoma
Infectious - hydatid cyst / neurocystercocosis / toxoplasmosis
Where is the most common location for an arachnoid cyst?
Middle temporal fossa
What is the Galassi classification of arachnoid cysts?
Why do arachnoid cysts grow?
Ball valve mechanism
Fluid production from the wall
What does head-bobbing suggest?
Large 3rd ventricle dilatation (pyramidal tract sign) LOOK UP
Large cyst within the brain, no oedema and no contrast uptake?
How do you resect a hydatid cyst?
Dowling's water dissection technique!
What is the incidence of a colloid cyst?
1 in a million person years
Why do you need an MRI for a brain tumour?
Surrounding Brain structures anatomy
Characterisation of the lesion
What are the management options for a brain tumour?
Surgery - biopsy / open
Depending on lesion - immunological / biological therapies
Approaches to a lateral ventricular lesion
Approaches to third ventricle
6 month old with cortical lesion, lots of oedema, string enhancement and seizures?
Desmoplastic infantile ganglioglioma
Which patients should you not do awake craniotomy on?
COPD as they don't ventilate well, CO2 rises and brain swells!
Is IDH1/2 seen in Pilocytic astrocytoma?
What is the management for oligos?
What are adjuvant therapies for LGG?
Radiation + PCV IF HIGH RISK = residual tumour
NEJM study Buckner et al 2016
When should you operate on a met?
Age < 65
Survival >6 months
3 or less lesions
Limited systemic disease