Techniques in Epilepsy Surgery: The MNI Approach

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Techniques in Epilepsy Surgery: The MNI Approach
Title
Copyright
Contents
Acknowledgment
Preface
1: History of epilepsy surgery
Introduction
Paul Broca (1824–1880)
William Macewen (1848–1924)
Victor Horsley (1857–1916)
Fedor Krause (1857–1937)
Harvey Cushing (1869–1939)
Otfrid Foerster (1873–1941)
Montreal Neurological Institute
Theodore Rasmussen (1910–2002)
Percival Bailey and the Gibbs
Murray Falconer (1910–1977)
Paulo Niemeyer (1914–2004)
Paul Crandall
Jean Talairach (1911–2007)
Gazi Yasargil
References
2: The search for the epileptic focus: investigation of the surgical candidate
Introduction
Concept of the epileptic focus
The limbic focus
The neocortical focus
Investigation of the surgical candidate
Initial patient evaluation
The seizure pattern(s)
EEG and video monitoring
Intracranial recording
Imaging
Spectroscopy
Volumetry
Nuclear imaging
Magneto-encephalography
EEG–Functional magnetic resonance imaging
Neuropsychology
Intracarotid memory and speech evaluation
Psychiatry
Epilepsy team
References
3: Surgical anatomy
Surgical anatomy
The gyral continuum
The gyral continuum over the lateral convexity
The gyral continuum over the mesial surface: the temporo-occipito-parietal region
The gyral continuum over the mesial surface: the frontal area
The gyral continuum over the inferior surface
Vascular considerations
The callosal grid
Construction of the callosal grid
Callosal planes (Figure 3.12)
Cerebral planes
The temporal grid
Display of the callosal grid on anatomical MRI and over the vasculature of the brain
Applications of the callosal grid (surgical anatomy)
Localization of lesions within various compartments or in reference to callosal planes
Surgical planning and postoperative evaluations
Application of the callosal grid as a brain-imaging (MRI) methodology
Conclusion
References
4: Neuronavigation and preoperative brain mapping
Introduction
Neuronavigation procedure
Preoperative data acquisition: MR and CT imaging
Functional activation data
Functional activation of speech areas
Operative procedure
Applications
Presurgical and topographic planning
Craniotomy
Topographic brain mapping
Electrocorticography (ECOG)
Removal of brain tumors
Surgery of cortical dysplasias
Temporal resections
Frontal resections
Central resections
Parieto-occipital resections
Callosotomy
Reoperations
Discussion
Accuracy of measurements and system limitations
Conclusion
References
5: Stereoelectroencephalography (stereotactic intracranial recording)
Introduction
Direct brain recording
Purpose of intracranial recording
Main indications for SEEG
Ambiguity of hemispheric lateralization
Ambiguity of intrahemispheric localization
SEEG in migration disorders
Preoperative magnetic resonance imaging
Integration of positron emission tomography with magnetic resonance imaging or functional magnetic resonance imaging
Target selection
Coverage of temporal lobe
Lateral orthogonal approach
Occipito-temporal approach
Coverage of the insula
Coverage of frontal lobe
Coverage of central area
Coverage of parieto-occipital area
Recording electrodes
Frameless electrode placement
Frameless stereotactic apparatus (Free Guide)
Robotic Assistance
Registration
Fixation of the optical reference device
Insertion of the Free Guide to the head clamp
Depth electrode placement
Step 1: Selection of trajectory to target
Step 2: Scalp punch
Step 3: Skull perforation
Step 4: Bone peg insertion
Step 5: Dural perforation
Step 6: Calculation of distance to target
Step 7: Insertion of ruler guide
Step 8: Placement of electrode
Step 9: Immobilization of electrode
Step 10: Electrode identification
Placement of cortical electrodes
Step 1: Identification of cortical sites
Step 2: Identification of scalp sites
Step 3: Skull perforation and peg insertion
Step 4: Placement of cortical epidural electrodes
Reference and ground electrodes
Dressing
Brain maps
Connecting the electrodes
Electrode montage and recording
Patient monitoring
Stimulation of depth electrodes
Head dressing and dressing care
Removal of electrodes
Results
Conclusion
References
6: Anesthesia and awake procedure
Historical perspective
Local anesthesia for awake craniotomy
General anesthesia for epilepsy surgery
References
7: Peroperative brain mapping
Introduction
History of human brain mapping
Electrocorticography
Mapping under local anesthesia: visual identification of the central sulcus
Stimulation of somatic motor and sensory areas
Cortical stimulation and parameters of stimulation
Identification of the tongue area under local anesthesia
Motor mapping under general anesthesia
Speech mapping
Functional imaging
Conclusion
References
8: Endopial resection (intervascular endopial gyral emptying)
Introduction
The rationale
Technique of intervascular multicompartment endopial gyral emptying
Subpial endopial resection examples
Anterior temporal resection
Selective amygdalohippocampectomy
Opercular resection
Frontal-parietal resection
Central resection
Illustrative case of central area resection
Conclusion
Reference
9: Surgery of temporal lobe epilepsy: cortico-amygdalohippo-campectomy
Introduction
Surgical anatomy of the temporal lobe
Temporal grid
White matter connections of the temporal lobe
Long association fibers
Circuit of Papez
Projection pathways
Commissural pathways
Amygdala
Visual radiations
Auditory area
Different modalities of temporal cortical resections
Temporal lobectomy
Cortico-amygdalohippocampectomy (CAH)
Technique of CAH
Head position
Scalp incision
Craniotomy
Topographic landmarks
Opercular arteries
Extent of resection
En bloc resection of neocortex
Resection of the mesial temporal structures
Cortico-amygdalectomy
References
10: Surgery of temporal lobe epilepsy: transcortical selective amygdalohippocampectomy
Introduction
Concept of mesial temporal lobe epilepsy
Concept of selective amygdalohippocampectomy
Transsylvian selective amygdalohippocampectomy
Subtemporal selective amygdalohippocampectomy
Stereotactic lesioning
The MNI selective amygdalohippocampectomy
Surgical technique
Preoperative imaging and planning
Positioning and registration
Pterional craniotomy approach
Keyhole approach
Cortical incision
Pitfalls of selective amygdalohippocampectomy
Corticoamygdalectomy
Tailored resections associated with a lesion of the temporal lobe
Advantages and disadvantages: selective versus non-selective resections
Seizure outcome: selective versus non-selective resections
Neuropsychological outcome: selective versus non-selective temporal resections
How selective is SelAH?
Conclusion
References
11: Surgery of central area epilepsy
Historical perspective
Central area anatomy and function
Topography
Somatotopic organization
Cortical structure
Connections of the central area
Functional anatomy of the central area
Central area vascular anatomy
Surgery of the central area
Stimulation under local anesthesia
Resections of the lower pre- and postcentral gyri
Resection in lower right central area: illustrative case
Illustrative case – left dominant
Resection of cavernous hemangioma: illustrative case
En bloc cortical central resections in the sensorimotor area
Multiple subpial cortical transections
Illustrative case
Pitfalls and complications of surgery in the central area
References
12: Surgery of frontal lobe epilepsy
Introduction
Historical perspective
Seizure patterns in frontal lobe epilepsy
Substratum of frontal lobe seizures
Strategies of investigation
Surgical anatomy
Overview of the frontal lobe
Sulcal anatomy
Gyral anatomy
Functional anatomy of the frontal lobe: main connection systems
Surgical strategy in frontal lobe epilepsy
Main surgical options in frontal lobe epilepsy in relation to etiology and localization
Surgical method and techniques of cortical resection
Scalp incisions and types of craniotomies
Dural opening
Cortical resection proper
Various types of frontal resections
Frontal lobectomy
Illustrative case
Anterior subtotal lobectomy
Illustrative case
Fronto-polar resections
Illustrative case: fronto-polar orbital
Paramedian frontal resections (medio-dorsal)
Illustrative case of F1 (mesio-dorsal resection)
Illustrative case of F1 (mesio-dorsal resection)
Lateral convexity resections
Illustrative case
Example of posterior F2 resection (lesionectomy)
Outcome of surgery: results on seizure tendency
Complications in frontal lobe surgery
Conclusion
References
13: Surgery of parietal lobe epilepsy
Introduction
Historical perspective
Surgical anatomy of the parietal lobe
Functional anatomy of the parietal region
Seizure patterns and clinical manifestations
Scalp incision and craniotomy
Technical pitfalls in parietal resections
Illustrative cases
Case A.H.
Case K.G.
Case L.M.
Surgical results
Conclusion
References
14: Surgery of insular lobe epilepsy
Introduction
Anatomy
Sulci
Gyri
Vascular
Functional anatomy
Insular epilepsy
Surgical approaches to the insula
Pitfalls
Illustrative case L.N.
References
15: Surgery of occipital lobe epilepsy
Introduction
Surgical anatomy of the occipital lobe
Functional anatomy of the occipital region
Seizure patterns and clinical manifestations
Occipital lobe surgery
Scalp incisions and craniotomies
Technical pitfalls in the occipital resections
Visual loss following occipital surgery
Neuronavigation
Case B.B.
Case T.
Case J.G.
Case H.
Results of surgery
Conclusion
References
16: Hemispherectomy
Introduction and historical perspective
Indications and preoperative evaluation
Surgical techniques
Step 1: Central resection
Step 2: Temporal lobectomy
Step 3: Callosotomy
Step 4: Anterior and posterior disconnections
Pitfalls
References
17: Callosotomy
Introduction and historical perspective
Physiological observations
Surgical anatomy
Patient selection
Preoperative evaluation
Callosotomy versus hemispherectomy
Surgical procedure
Preoperative – preparation
Positioning
Scalp incision
Craniotomy
Dural opening
Interhemispheric dissection and separation of the hemisphere
Callosotomy proper
Reoperation and extension of callosotomy
Anterior approach
Posterior approach
Positioning
Dealing with ascending veins
Interhemispheric approach
Transection of the splenium proper
Results of callosotomy on seizure tendency
Conclusion
References
18: Epilepsy and brain tumors
Incidence of epilepsy as a symptom of brain tumor
Pathophysiology
Clinical presentation
Investigation of the epileptic tumor suspect
Tumor diagnosis
Seizure focus identification
Surgical treatment
Surgical techniques
Local or general anesthesia
Scalp incisions and craniotomy
Intraoperative cortical mapping
Cortical resection: general principles
Resection methods and illustrative cases
Frontal tumors
Illustrative case L.C.
Central tumors
Illustrative case P.Y.
Illustrative case C.A.
Temporal neocortical tumors
Example of neocortical tumor within left dominant temporal lobe: Case N.A.
Parietal area lesions
Illustrative case A.O.
Distribution of benign gliomas with seizures
Temporal lobe gliomas
Frontal lobe gliomas
Gliomas of the frontal, central, parietal, and occipital areas
Tumor recurrence
Discussion
Conclusion
References
19: Surgical treatment of cortical dysplasias
Introduction
Development of cerebral cortex and pathogenesis of dysplasias
Classification of dysplasias
Their association with tumor
Location, size and extent
Epileptogenicity
Surgical approach
Distribution according to regions and pathology
Dysplasia of right temporal area
Dysplasia of right frontopolar area
Dysplasia of left frontal cingulate area
Outcome in temporal lobe resections
Outcome in frontal lobe resections
Outcome in extra-temporal and extra-frontal resections
Outcome of callosotomy
Surgical complications
Discussion
Size of lesion
Location of lesions
Relationship to the electrically defined epileptogenic area
Relationship of dysplastic lesions to tumor
Conclusion
References
20: Reoperations in failed epilepsy surgery
Introduction
Preoperative evaluation
Indications for reoperations
Technical aspects of reoperation in temporal lobe epilepsy
Outcome of reoperations in temporal lobe epilepsy
Causes of seizure recurrence after temporal lobe surgery
Results of surgery and morbidity following reoperation for temporal lobe epilepsy
Reoperation for extra-temporal lobe epilepsy
Reoperations after callosotomy
Conclusion
References
21: Alternative procedures in surgery for epilepsy
Introduction
Multiple subpial transections
Indications
Surgical technique
Pitfalls
Vagus nerve stimulation
Indications
Surgical technique
Mechanism of action
Conclusion
Brain stimulation
Mechanism of action
Anterior nucleus of thalamus stimulation
Intracerebral and cortical stimulation
Gamma Knife radiosurgery
Hypothalamic hamartoma
Medial temporal lobe epilepsy
Intracerebral drug delivery
Gene- and cell-based therapies for epilepsy
Gene therapy for epilepsy
Cell-based therapy for epilepsy
Conclusion
References
22: Complications of epilepsy surgery
Introduction
Definition of a complication
Complications of invasive recordings
Complications of craniotomy
Surgical complications
Neurological complications
Callosotomy
Miscellaneous complications
Neuronavigation
Conclusion
References
23: Quality of life after epilepsy surgery
Introduction
Quality of life after temporal lobe epilepsy surgery
Quality of life after extra-temporal lobe epilepsy surgery
Conclusion
References
Index