Wernicke area high-grade glioma

Introduction

Historically, the Wernicke area has been defined as residing primarily within the posterior superior temporal lobe in the dominant hemisphere. ^, However, there is great individual variability. ^, The methods of identifying this area radiographically primarily involve functional magnetic resonance imaging (MRI), in which neurovascular coupling allows the identification of flow changes in conjunction with neuronal activity. The difficulty with functional MRI is that it is prone to false positives and false negatives, does not identify critical functional thresholds, and can be less sensitive and/or specific in tumor-infiltrated and/or edematous areas that are common for gliomas, especially high-grade gliomas. The direct method of identifying these areas is awake brain mapping with direct electrical stimulation, whereby electrical stimulation impairs normal neurologic firing to identify functional processes. In this chapter, we present a case of a high-grade glioma in close proximity to the superior temporal gyrus, which has historically been identified as the Wernicke area.

Example case

Chief complaint: speaking difficulties

History of present illness

A 51-year-old, right-handed man with a history of hypertension presented with difficulty speaking. Over the past 2 months, he has noticed an increased difficulty getting the right words out, especially during business meetings. He has also had several instances in which his words did not sound right. He underwent brain imaging that revealed a brain lesion ( Fig. 20.1 ).

Medications : Hydrochlorothiazide.
Allergies : No known drug allergies.
Past medical and surgical history : Hypertension.
Family history : No history of intracranial malignancies.
Social history: Business executive, no smoking or alcohol history.
Physical examination : Awake, alert, oriented to person, place, and time; Language: slowness in speech, dysarthria, intact naming and repetition; Cranial nerves II to XII intact; No drift, moves all extremities with full strength.
Imaging : Chest/abdomen/pelvis imaging negative for primary malignancy.

	Mitchel S. Berger, MD, University of California at San Francisco, San Francisco, CA, United States	Shawn L. Hervey-Jumper, MD, University of California at San Francisco, San Francisco, CA, United States	Manabu Natsumeda, MD, PhD, Niigata University, Niigata, Japan	Pierre A. Robe, MD, PhD, University Medical Center of Utrecht, The Netherlands
Preoperative
Additional tests requested	DTI MEG	DTI MEG Neuropsychological assessment	fMRI DTI Neuropsychological assessment Angiography and Wada test 3D-CTA/CTV	Neuropsychological assessment
Surgical approach selected	Left temporal-parietal craniotomy with awake language and motor cortical and subcortical mapping with 5-ALA	Left temporal craniotomy with awake language mapping with 5-ALA	Left parietal awake craniotomy with cortical and subcortical mapping	Left temporo-parietal awake craniotomy with cortical and subcortical mapping with 5-ALA
Anatomic corridor	Left temporal-parietal with awake cortical and subcortical mapping	Left STG	Left parietal	Left posterior temporal
Goal of surgery	Complete resection of the enhancing and as much FLAIR as possible	Maximal resection of enhancing core and FLAIR with minimal language morbidity	Complete resection of the enhancing and as much FLAIR as possible	Maximal resection of FLAIR according to functional boundaries
Perioperative
Positioning	Left supine	Left semilateral	Right lateral (left side up)	Left park bench
Surgical equipment	Surgical navigation Surgical microscope with 5-ALA Brain stimulator	Surgical navigation IOM (ECoG) Surgical microscope with 5-ALA Brain stimulator Ultrasonic aspirator	Surgical navigation IOM (MEP/SSEP) Brain stimulator Surgical microscope with 5-ALA Intraoperative CT	Surgical navigation Ultrasound Neuropsychological testing Surgical microscope
Medications	Mannitol Steroids Antiepileptics	Mannitol Steroids Antiepileptics	Mannitol Steroids Antiepileptics	Steroids Mannitol
Anatomic considerations	Language cortical and subcortical areas	STG, MTG, SLF, AF, IFOF, uncinate, ILF, MdLF	Angular artery, temporal occipital artery, SMG, AG, STG, AF, IFOF, MdLF, Sylvian fissure, vein of Labbe	Temporal cortex, optic radiations, IFOF
Complications feared with approach chosen	Language deficits	Long-term language deficits	Language dysfunction, Gerstmann syndrome, visual field deficit	Speech deficit, prosopagnosia, working memory deficit, quadrantopsia
Intraoperative
Anesthesia	Asleep-awake-asleep	Asleep-awake-asleep	Asleep-awake-asleep	Awake
Skin incision	Inverted U	Inverted U	Horseshoe	Semicircular, supraauricular
Bone opening	Left temporal-parietal with 2-cm margin	Left temporal	Left temporal-parietal	Left temporal-parietal
Brain exposure	Left temporal-parietal	Left temporal	Left temporal-parietal	Left temporal-parietal
Method of resection	Skin anesthetized, craniotomy overlying lesion with 2-cm margin based on navigation, dural opening, awake language cortical mapping, corticectomy based on negative mapping areas, continue resection with continuous subcortical language mapping, aim to resect all enhancement as well as FLAIR pending mapping results, resection until positive cortical and subcortical mapping, 5-ALA fluorescence assessemnts for residual, watertight dural closure, subgaleal drain insertion	Local anesthetic into pins sites, wide scalp block, myocutaneous flap extended inferiorly, confirm body temperature and optimal mapping conditions, mapping team present including neurology and speech pathology, language mapping over STG and MTG to determine positive mapping threshold, mapping over tumor site with 1-cm margin around FLAIR, entry into functional free zones with ultrasonic aspirator, resection first along anterior and medial FLAIR margins subpially and then lateral margin down to subcortical U-fibers, mass truncated at bottom of sulcus, subcortical stimulation until medial margin reached	Scalp bloc, LMA, craniotomy based on navigation, awaken patient and removal of LMA, language mapping, corticectomy based on negative mapping results, resection of enhancing portion with ultrasonic aspirator and suction, check for 5-ALA staining, removal of FLAIR portion until positive mapping areas reached, patient put back to sleep with LMA, continuous monitoring, intraoperative CT to guide further resection, watertight dural closure, insertion of subgaleal drain	Local field block, myocutaneous opening, left temporal/pterional bone flap, ultrasound to delineate tumor margins, opening dura, ECoG, cortical stimulation for positive sites (1–3 mA), tumor resection with repetitive cortical and subcortical stimulation, decrease simulation to 2 and 1 mA near eloquent area, ultrasound to evaluate extent of resection and hematoma
Complication avoidance	Language mapping, continuous monitoring	Language mapping, subcortical mapping once sulcus level reached	Language mapping, continuous monitoring, intraoperative CT	Cortical and subcortical stimulation, ultrasound
Postoperative
Admission	ICU	ICU	ICU	Floor
Postoperative complications feared	Language dysfunction, seizures	Language dysfunction, venous infarct	Language dysfunction, Gerstmann syndrome, visual field deficit	Language dysfunction, vasospasm, seizure
Follow-up testing	MRI within 24 hours after surgery with DWI and DTI	MRI within 48 hours after surgery Speech evaluation 24 hours after surgery	CT immediate postoperative MRI within 24 hours after surgery Neuropsychological assessment 7 days after surgery	MRI within 72 hours after surgery Postoperative neuropsychological assessment and 3 months after surgery
Follow-up visits	10 days after surgery with neurooncology	14 days after surgery	On pathology diagnosis	As needed with neurosurgery Speech therapy
Adjuvant therapies recommended
IDH status	Mutant–radiation/temozolomide +/– lomustine Wild type–radiation/temozolomide +/– lomustine	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide with TTF Wild type–radiation/temozolomide with TTF	Mutant–radiation/temozolomide Wild type–radiation/temozolomide
MGMT status	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide under 65 years of age	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–radiation/temozolomide +/– TTF Unmethylated–radiation/temozolomide +/– TTF	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide