Presentation on theme: "Awake Craniotomy: Role in Neurosurgical Management Christine Stewart University of Minnesota, MS4."— Presentation transcript:
Awake Craniotomy: Role in Neurosurgical Management Christine Stewart University of Minnesota, MS4
Outline Case R.P. Classic indications and exclusion criteria Factors to consider when defining eloquent areas Recommendations
R.P. 42 RHM w/ long history of seizures recently changed in character, worsening H/A over past several months. Wife notes increasing apathy, slow processing Difficulty with word-finding, long-term memory, mood-swings Other PMHx: – Cyclist v. car 1983: LOC 1-2 minutes, right frontal frx w/ CSF leak meningitis – 1 st seizure 1985 GTC w/ auras – Another episode of meningitis 1985 intracranial abscess R. frontal lobe R. frontal craniotomy – Imaging from 2002-2008 show a hypodensity in the left frontal lobe which was interpreted as encephalomalcia given hx – Hypothyroidism Medications: – Lamictal 400 mg – Vimpat 200 mg BID – Levothyroxine
Classic Indications for Awake Craniotomy 1 Surgery in ‘eloquent’ brain – Near motor strip – Speech/language centers – Thalamus Removal of brainstem tumors Search for a focus of seizure activity
Exclusion Criteria 2,3, 4 Inability to cooperate: dysphasia, language barrier, emotional labiality, cognitive impairment Low occipital tumors Tumors with significant dural attachment Patients < 11 years old 5
Eloquent areas and factors to consider: Anatomical variability 6 – ICBM 452 atlas “Average” brain – Factors: sex, age, handedness, neurological and psychiatric disease
Eloquent areas and factors to consider: Functional variability 6,7,8 – Even areas with the same anatomical landmarks may not harbor the same underlying function Motor cortex variability: – “Hand knob” of pre-central gyrus can represent primary motor cortex or premotor cortex – Stimulation in pre-central cortex can result in sensory and motor responses or motor responses in > 1 motor group – Primary motor area may extend > 20 mm anterior to the central sulcus
Eloquent areas and factors to consider: Functional variability Variability in language cortices 6 – > 4cm of variability in intraoperative speech arrest J Neurosurg 71:316–326, 1989.
Eloquent areas and factors to consider: Effect of space-occupying lesions – Unusual functional acquisition: congenital lesions (AVMs) higher incidence right v. left sided language 6 – Reorganization: LGG (low grade gliomas)/other adult neurological injury reorganization of speech center s.t more frontal speech centers in pt vs. controls 10 – Extent likely depends on time-course of injury 9 – Illustratively, these patients rarely present with neurodeficits 9
Variability in Mapping Functional Localization 2,6 Either measuring electrophysiological signals or perfusion Electrocortical stimulation mapping (ESM) identifies essential and involved areas – Other methods seem to be more sensitive to map all involved areas, but do not identify which are essential If essential area is identified: – Appropriate resection margins have not been recommended
Effects of Mapping 4 % of all patients% w/ post-op neurodeficits % w/ deficits who were previously intact + Mapping22.5%20.9%4.4% - Mapping77.5%13.5%1.8%
When considering awake craniotomy: Outcomes – No prospective randomized control trial has been done directly comparing awake v. GA 3 Patient experience – Awake procedures are well-tolerated 11 Overall satisfaction rated: 71-93% Significant pain identified: 8-29% All of this literature asks post-op and relies on recall – Non-language deficits are noted after surgeries done under GA 2 Visual, spatial perceptions, cognitive and behavioral disorders noted as more individuals do neuropsychological testing. Cost 4 – Reduces operating time Dependent on experience level – Reduces post-op ICU stay – Reduces total hospital stay Median LOS: 1 day
Recommendations No ‘gold standards’ for pre-operative mapping b/c no outcomes-correlated evidence – fMRI at minimum – DTI may help define white matter tracts in and around the lesion – Others: MEG, PET Intra-operative monitoring should be mandatory – only technique with validated outcomes measures
References 1 Greenberg, M. Handbook of Neurosurgery. 7 th edition. 2 Duffau, H. Awake surgery for non-language mapping. Neurosurgery. 66:523-529, 2010. 3 Kirsch, B. and Bernstein, M. Ethical challenges with awake craniotomy for tumor. Can. J. Neurol Sci 39: 78-82, 2012. 4 Serletis, D. and Bernstein, M. Prospective study of awake craniotomy used routinely and non- selectively for supratentorial tumors. J Neurosurgery. 107:1-6, 2007. 5 Berger, MS. The impact of technical adjuncts in surgical management of cerebral low grade gliomas of childhood. J. of neuro-oncology. 1996; 28:129-155. 6 Pourtrain, N. and Bookheimer, S. Reliability of anatomy as a predictor of eloquence: a review. Neurosurg Focus 28:E3, 2010. 7 Shinoura N, Suzuki Y, Yamada R, Tabei Y, Saito K, Yagi K:Precentral knob corresponds to the primary motor and premotor area. Can J Neurol Sci 36:227–233, 2009 8 Uematsu S, Lesser R, Fisher RS, et al: Motor and sensory cortex in humans: topography studied with chronic subdural stimulation. Neurosurgery 31:59–72, 1992 9 Desmurget M, Bonnetblanc F, Duffau H: Contrasting acute and slow-growing lesions: a new door to brain plasticity. Brain 130:898–914, 2007 10 Lucas TH II, Drane DL, Dodrill CB, Ojemann GA: Language reorganization in aphasics: an electrical stimulation mapping investigation. Neurosurgery 63:487–497, 2008 11 Manchella, S. et al. The experience of patients undergoing awake craniotomy for excision of intracranial masses: expectations, recall, satisfaction and functional outcome. British Journal of Neurosurgery. June 2011. 25(3): 391-400.