Left temporal low-grade glioma

Introduction

A common location of low-grade gliomas (LGGs) is the temporal lobe. In most series, this number ranges from 15% to 25%. Patients with temporal lobe LGGs typically have subtle deficits, in which patients with left temporal lobe lesions typically have more deficits in attention, object naming, and language as compared with right temporal lesions. Moreover, patients with left temporal glioma function poorer on neurocognitive tests than patients with right temporal gliomas. In this chapter, we present a case of a left temporal lobe LGG.

Example case

Chief complaint: seizures

History of present illness

A 26-year-old, right-handed woman with no significant past medical history presented with confusion and possible seizures. Over the past several months, her family has noted that she has several episodes in which she stares for several seconds and has several minutes of confusion following these events. They deny any loss of consciousness, tongue biting, and/or bowel/bladder incontinence. In addition, she has intermittent episodes in which she has trouble speaking. She saw her primary care physician who ordered brain imaging, which revealed a brain tumor ( Fig. 10.1 ). She was referred for further evaluation and management.

Medications : None.
Allergies : No known drug allergies.
Past medical and surgical history : None.
Family history : No history of intracranial malignancies.
Social history : Nursing student. No smoking or alcohol.
Physical examination : Awake, alert, oriented to person, place, and time; Language: intact naming and repetition; Cranial nerves II to XII intact; No drift, moves all extremities with full strength.

	Jeffrey N. Bruce, MD, Columbia University, New York, NY, United States	Victor Garcia-Navarro, MD, Tec de Monterrey Institute, Campus Guadalajara, Mexico	John S. Kuo, MD, PhD University of Texas at Austin, Austin, TX, United States	Pierre A. Robe, MD, PhD, University Medical Center of Utrecht, The Netherlands
Preoperative
Additional tests requested	DTI fMRI Neuropsychological assessment	fMRI, DTI, MRS Perfusion MRI (CBF/CBV) Neuropsychological assessment and language evaluation	fMRI Wada (sodium amytal) test Neuropsychological assessment	Neuropsychological assessment
Surgical approach selected	Left fronto-temporal awake craniotomy with speech and motor mapping	Left fronto-temporal awake craniotomy with speech and motor mapping	Left fronto-temporal craniotomy	Left temporal awake craniotomy with ECoG and cortical and subcortical mapping
Anatomic corridor	Left fronto-temporal	Left temporal	Left fronto-temporal	Left temporal
Goal of Surgery	Extensive resection with functional preservation	Diagnosis, maximal safe resection, seizure control	Diagnosis, maximal safe resection	Tumor removal to limits of neurocognitive function
Perioperative
Positioning	Left supine with right rotation	Left semilateral	Left supine with right head rotation	Left park bench
Surgical equipment	Surgical navigation IOM (ECoG) Brain stimulator Ultrasound Ultrasonic aspirator Surgical microscope	Surgical navigation Ultrasound Brain stimulator IOM (ECoG) Ultrasonic aspirator	Surgical navigation Surgical microscope Ultrasound	Surgical navigation Ultrasound Neuropsychological testing IOM (EcoG) Surgical microscope
Medications	Steroids Antiepileptics	Steroids Antiepileptics Hypertonic saline	Steroids Antiepileptics Mannitol, furosemide	Steroids Mannitol
Anatomic considerations	Sylvian fissure, speech and motor areas	MCA perforators, cortical and bridging veins, motor and language tracts	Sylvian fissure, MCA and branches, anterior choroidal artery, temporal ventricular horns, perimesencephalic cisterns	Temporal cortex, optic radiations, IFOF
Complications feared with approach chosen	Language dysfunction, motor deficit, memory loss	Transient or permanent motor deficit, language or memory deficit, stroke	Speech deficit	Speech deficit, prosopagnosia, working memory deficit, quadrantopsia (upper right)
Intraoperative
Anesthesia	Asleep-awake-asleep	Asleep-awake-asleep with bispectral index	General	Awake-awake-awake
Skin incision	Curvilinear/pterional	C-shaped	Pterional	Question mark
Bone opening	Left fronto-temporal	Left fronto-temporal		Left fronto-temporal
Brain exposure	Left fronto-temporal	Left fronto-temporal	Left fronto-temporal	Left temporal
Method of resection	Monitored anesthesia care for opening, large fronto-temporal craniotomy and removal of lesser sphenoid wing, U-shaped dural opening based on sphenoid wing, ECoG grid, patient awoken, speech and motor mapping, identify margins based on navigation, resection starting at STG and dissecting from Sylvian fissure based on negative mapping of speech and motor, debulk tumor with ultrasonic aspirator, dissection from speech and motor fibers, ultrasound to guide further resection, watertight dural closure	Patient awakened, C-shaped dural incision and motor mapping to confirm a positive response, stimulation intensity determined by progressively increasing amplitude, language (counting, picture-naming tasks) mapping, eloquent areas marked by sterile number, ultrasound performed, transcortical subpial temporal lobectomy with lesionectomy, hippocampus and amygdala are identified in the temporal horn and tumor resected, functional structures determined by cortical and subcortical stimulation and represent the limits of surgery, goal is supramarginal resection, final ECoG and ultrasound to assess resection	Myocutaneous flap, left fronto-temporal craniotomy based on navigation, confirm location of Sylvian fissure, dural opening with copious antibiotic-impregnated irrigation, left anterior temporal lobectomy 4 cm from temporal tip, remove en bloc if possible under microscopic visualization, remove posterior and deep margins based on navigation, identify deep vasculature (MCA, anterior choroidal), use ultrasound to identify temporal ventricular horns and basal cisterns, protect with gelfoam, watertight dural closure	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	Cortical and subcortical brain mapping, ultrasound	Preservation of bridging veins, motor and language mapping, resection to functional boundaries, ultrasound, ECoG	Limit temporal lobectomy to 4 cm from anterior edge of temporal lobe, en bloc resection, navigation-guided additional resection, ultrasound	ECoG, cortical and subcortical stimulation, ultrasound
Postoperative
Admission	ICU	ICU	ICU	Floor
Postoperative complications feared	Language dysfunction, short-term memory loss, motor deficit, seizures	Seizures, stroke	Seizures, speech deficit	Vasospasm, seizures, CSF leak
Follow-up testing	MRI within 48 hours after surgery	CTA within 24 hours after surgery MRI within 72 hours after surgery	MRI within 24 hours after surgery	MRI within 72 hours after surgery
Follow-up visits	7 days after surgery	7 days after surgery	2 weeks after surgery	As needed
Adjuvant therapies recommended
Diffuse astrocytoma (IDH mutant, retain 1p19q)	GTR–radiation/temozolomide STR–radiation/temozolomide	GTR–observation STR–temozolomide, possible radiation or repeat resection with recurrence	GTR–observation STR–second look surgery if resectable, neuro-oncology and radiation oncology evaluation if not resectable	GTR–radiation/temozolomide STR–radiation/temozolomide
Oligodendroglioma (IDH mutant, 1p19q LOH)	GTR–observation STR–radiation/temozolomide or observation	GTR–observation STR–PCV or temozolomide, possible radiation or repeat resection for recurrence	GTR–observation STR–second look surgery if resectable, neuro-oncology and radiation oncology evaluation if not resectable	GTR–observation/discussion STR–radiation/PCV
Anaplastic astrocytoma (IDH wild type)	GTR–radiation/temozolomide STR–radiation/temozolomide	GTR–radiation/temozolomide STR–radiation/temozolomide	STR–second look surgery if resectable, radiation/chemotherapy GTR–radiation/chemotherapy	GTR–radiation/temozolomide STR–radiation/temozolomide