Epilepsy Surgery Flashcards
Factors that suggest good postsurgical outcomes
- Later age at onset
- Shorter duration of epilepsy
- presence of febrile seizures
- Positive MRI or PET
- Unilateral findings on PET
- Concordant data (between MRI/PET/EEG)
- lack of need for intracranial monitoring
MRI sequence best to identify subtle features of temporal lobes (MTS, incomplete hippocampal inversion)
Oblique coronal
Criteria for MTS
Main (3)
Other features you may see (5
Main
- hippocampal atrophy
- increased T2 signal
- abnormal morphology or loss of internal architecture of hippocampus
Secondary features
- dilation of temporal horn of lateral ventricle
- Loss of gray-white matter differentiation in the temporal lobe
- decreased white matter in the adjacent temporal lobe
- atrophy of ipsilateral forinx
- atrophy of mamillary body
% of MTS cases that are bilateral
10%
What 3 things do you see in this picture?
- Enlargement of left lateral ventricle temporal horn
- left hippocampus smaller and hyperintense compared to contralateral side
- Left hippocampus is abnormally smooth
What 3 things do you see in this picture
Left hippocampal volume loss
- Hyperintense hippocampus
- subtle laminar blurring
What sequence is this?
What is this showing?
- T2-waited image
- globular let hippocampus
What sequence is this?
What is the arrow showing? (1+2
-T2-weighted image
Showing incomplete hippocampal inversion
- More vertical left collateral sulcus
- Low-lying left body of the fornyx
What sequence is this?
What is this showing?
- Coronal Flair
- FLAIR hyperintensity in bilateral MTS
What is this sequence?
What is this showing?
T2 waited
- laminar blurring bilateral MTS
What is this sequence?
What is this showing? (2)
Coronal T2
Right volume loss and laminar blurring (Right MTS and right fornix atrophy)
What is this Sequence?
What is this showing?
- 3D T1-weighted image
- volume loss in bilateral MTS
What are these sequences?
What is this showing?
Small Gray matter heterotopia on T2-weighted(B), but better seen on Coronal double-inversion (C) and T1 (D)
What are these sequences?
What are they showing?
Axial + coronal T2 (A+B), Coronal Flair (C)
small emphalocele in fusiform gyrus extending to right foramen ovale
What is this sequence
What is this showing (2)
Coronal FLAIR
- gray-white Blurring
- FLAIR hyperintensity in left frontal anterior cingulate gyrus (FCD)
What is this sequence
What is this showing (2)
Axial FLAIR sequences
- gray-white Blurring
FLAIR hyperintensity in left medial frontal gyrus (FCD)
What are these sequences?
what do they show?
- T1-weighted (A) and Axial FLAIR (B)
- Pachygyria
What are these sequences? (2)
What are they showing?
- Coronal and axial FLAIR
- thickened cortex in right posterior sylvian fissure (Polymicrogyria)
What are these sequences? (2)
What are they showing?
- Sagittal and axial post-contrast T1
- Thickened cortex extending from right sylvian fissure toward vertex (Polymicrogyria)
What are these sequences?
What are they showing
Coronal / Axial FLAIR (A,B) and Sagittal/Axial Post-contrast T1 (CD)
- thickened cortex in right posterior sylvian fissure, extending to vertex (Polymicrogyria)
Symptoms of a common side effect syndrome following :
ANTERIOR corpus callosotomy (3)
POSTERIOR Corpus Callsotomy (2)
TOTAL callostomy (4)
Anterior disconnection syndrome
- Mutism
- left leg paresis
- urge urinary incontinence
Posterior acute disconnection syndrome
- tactile transfer deficits
- visual transfer defects
TOTAL / near total resection: Split brain syndrome
- language impairment
- disordered attention
- disordered memory sequencing
- hemisphere competition
What type of electrodes are best used to detect DC shift?
What is the best Time constant?
What type of impedence?
Platinum electrodes
long time constant
High impedence
What is included in a “standard” anterior temporal lobectomy (4 + one omitted)
- amygdala
- hippocampus
- parahippocampal gyrus
- 3.5-4 cm of lateral temporal neocortex
NOT resected: - Superior temporal gyrus
what is included in a selective amygadlo-hippocampectomy (3 + omitted)
- amygdala
- hippocampus
- limited resection of parahippocampal gyrus
NOT resected: - temporal neocortex