Right perirolandic high-grade glioma

Introduction

The surgery of brain tumors, namely gliomas, requires a delicate balance between extensive resection and avoidance of neurologic deficits. The risk of neurologic deficits is highest in those tumors that involve eloquent motor and/or language cortical and subcortical regions. There are a variety of methods for monitoring these pathways, which include passive monitoring, including motor evoked potentials (MEP) and somatosensory evoked potentials (SSEP), as well as direct monitoring, including cortical stimulation. These methods are most utilized for lesions involving motor pathways. In this chapter, we present a high-grade glioma that is in close proximity and possibly involves the perirolandic region and corticospinal tracts in the nondominant hemisphere.

Example case

Chief complaint: left-sided weakness

History of present illness

A 41-year-old, right-handed man with no significant past medical history presented with progressive left-sided weakness. Over the past 3 weeks, he developed progressive left arm and leg weakness to the point in which he could not button his shirt and was dragging his leg while he was walking. He was seen by his primary care physician who ordered brain imaging that revealed a brain lesion ( Fig. 17.1 ). He was referred for evaluation and management.

Medications : None.
Allergies : No known drug allergies.
Past medical and surgical history : None.
Family history : Father died of glioblastoma within the last couple of months.
Social history : Works as an engineer. No smoking history or alcohol.
Physical examination : Awake, alert, oriented to person, place, and time; Cranial nerves II to XII intact; Left drift, left upper extremity 4/5, left lower extremity 4+/5, right upper extremity/right lower extremity 5/5.
Imaging : Chest/abdomen/pelvis computed tomography negative for primary malignancy.

	Mark Bernstein, MD, University of Toronto, Toronto, Canada	Chetan Bettegowda, MD, PhD, Johns Hopkins University, Baltimore, MD, United States	Randy L. Jensen, MD, PhD, University of Utah, Salt Lake City, UT, United States	Eslam Mohsen Mahmoud Hussein, MBBS, MSc, Ain Shams University, Cairo, Egypt
Preoperative
Additional tests requested	DTI fMRI	DTI	DTI	DTI fMRI Neuropsychological assessment
Surgical approach selected	Right frontal awake craniotomy for tumor for motor and sensory mapping	Right frontal craniotomy with tubular retractor and asleep motor mapping	Right frontal-parietal craniotomy for tumor with asleep cortical mapping and intraoperative MRI	Right posterior frontal or parieto-occipital craniotomy
Anatomic corridor	Right frontal	Right frontal lateral and anterior to motor cortex	Right frontal	Right posterior frontal
Goal of surgery	Maximal safe resection of enhancing portion of the tumor	Gross total resection of enhancing component	Gross total resection of enhancing component	Gross total resection of enhancing component
Perioperative
Positioning	Right supine with left rotation	Right supine	Right supine 30-degree rotation	Right supine with left rotation
Surgical equipment	Surgical navigation Surgical microscope Brain stimulator	Surgical navigation IOM (MEP, SSEP, EEG) Brain stimulator Surgical microscope Tubular retractors	Surgical navigation Ultrasonic aspirator Brain stimulator IOM (SSEP/MEP/phase reversal) Intraoperative MRI	Surgical navigation Ultrasonic aspirator Surgical microscope
Medications	Steroids	Steroids Antiepileptics Mannitol	Steroids	Steroids Antiepileptics Mannitol Diuretics
Anatomic considerations	Precentral gyrus	Precentral gyrus, SMA, internal capsule	Central sulcus, precentral gyrus	Precentral gyrus
Complications feared with approach chosen	Motor deficit	Motor deficit	Motor deficit	Motor deficit
Intraoperative
Anesthesia	Asleep	General	General	General
Skin incision	Linear	Linear	Linear/curvilinear	Linear
Bone opening	Right frontal	Right frontal	Right frontal-parietal	Right posterior frontal or parieto-occipital
Brain exposure	Right frontal	Right frontal	Right frontal-parietal	Right posterior frontal or parieto-occipital
Method of resection	Regional field block with local anesthetic, craniotomy based on navigation over lesion, cruciate dural opening, motor and speech mapping with electrocortical stimulation, find pseudoplane between tumor and normal parenchyma, stay 1 cm away from positive mapping sites, periodic confirmation with navigation, close when satisfied with maximal resection	Craniotomy to encompass lesion based on navigation, cruciate dural opening, placement of strip electrode and phase reversal to identify motor cortex, stimulate cortex to confirm absence of motor cortex, small corticectomy over negative motor mapping site, place tubular retractor into hematoma, debulk hematoma to reduce mass effect, debulk remaining tumor with continuous subcortical mapping	Craniotomy based on navigation, dural opening, placement of strip electrode, and phase reversal assessment, identify tumor volume based on navigation, cortical mapping to confirm absence of motor cortex, corticectomy over negative mapping sites, microscopic guided resection with continuous MEP, subcortical mapping as needed for deep portion of tumor, intraoperative MRI when maximal resection anticipated, further resection with recalibrated navigation if necessary	Larger craniotomy to avoid postoperative edema, monitor for increased intracranial pressure based on dural pulsation, cruciate dural opening if not tense, trajectory based on DTI and navigation, small corticectomy over nonfunctional areas, attempt to find a cleavage plane, debulk tumor without violating neural structures, expansile duraplasty if brain swelling, closure with subgaleal drain
Complication avoidance	Awake motor and speech mapping, staying 1 cm away from positive mapping sites	IOM, cortical and subcortical mapping	IOM, cortical and subcortical mapping, intraoperative MRI	DTI, finding cleavage plane around tumor
Postoperative
Admission	Outpatient	ICU	ICU	ICU
Postop complications feared	Motor deficit	Seizures, motor deficit, hydrocephalus, intraventricular hemorrhage	Motor deficit	Motor deficit, seizure, altered mental status
Follow-up testing	CT within 4 hours after surgery MRI prior to radiation	CT immediately after surgery MRI within 24 hours after surgery Physical and occupational therapy	MRI within 48 hours after surgery	CT with and without contrast within 48 hours after surgery MRI before radiation therapy
Follow-up visits	10–14 days after surgery and follow-up with radiation and neurooncology	14 days after surgery	2–4 weeks with neurooncology 4–6 weeks after surgery	10 days after surgery
Adjuvant therapies recommended
IDH status	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–whole brain radiation/temozolomide or bevacizumab Wild type–whole brain radiation therapy, neurooncology evaluation
MGMT status	Methylated–radiation/temozolomide Unmethylated–radiation/ temozolomide	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–whole brain radiation/temozolomide or bevacizumab Unmethylated–whole brain radiation therapy, neurooncology evaluation