Brain mapping for lesions in primary motor cortex: integrated surgical approach

Abstract

Background
Lesions within the corticospinal tract (CST) represent significant surgical challenge with a delicate functional trade-off that should be integrated in the overall patient-centred treatment plan.

Methods
Patients with lesions within the CST with preoperative cortical and subcortical mapping (nTMS and tractography), intraoperative mapping and intraoperative provisional histological information (smear +- 5-ALA) were included. This independently acquired information was integrated in a decision-making process model to determine the intraoperative extent of resection.

Results
10 patients (6 patients with metastatic precentral tumour; 1 patient with Grade III and 2 patients with grade IV gliomas; 1 patient with precentral vascular malformation) were included in the study. Majority of the patient had pre-operative motor deficit (60%). 50% patients underwent gross total resection and 40% patients underwent near total resection of the lesions. In only one patient, no surgical resection was possible after both pre-operative and intraoperative mapping. 70% of patients remained stable postoperatively and 20% improved from previous motor weakness.

Conclusion
The independently acquired anatomical (anatomical MRI) and functional (nTMS and tractography) in patients with CST lesions provide a more accurate guide for resection. The inclusion of the histological information (smear +- 5-ALA) further allows the surgical team to balance the potential functional risks within the global treatment plan. Therefore, the patient is kept at the centre of the informed decision making process.

Full text

Abstracts
iv18 NEURO-ONCOLOGY • Oc t O b e r 2019
with low grade glioma underwent awake craniotomy using the Modus
V. Qualitative feedback (semi-structured interview) was received from
the MDT including surgeons, occupational/ speech and language/ physio-
therapists, neurophysiologists, anaesthetists and scrub team. Optimal device
positioning is described. RESULTS: Both female patients (38 and 52years
old) underwent surgery between December 2018 and February 2019. Le-
sions were located in right perisylvian and posterior inferior frontal gyrus
locations respectively.
Surgical resection was satisfactory. Patient 1 developed a wrist-drop intra-
operatively. Patient 2 had transient mild word nding difculties. Surgeons
reported easier surgical ow with hands-free positioning, larger working
area and improved ergonomics. Adapting to non-stereoscopic vision in-
creased operating times. Multi-disciplinary team members reported an
better communication with the operating surgeon during patient assessment
and a more involved educational experience. CONCLUSION: Hands-free
exoscopes may provide improved surgical ow and efciency for awake cra-
niotomy whilst simultaneously improving multidisciplinary communication
and education. There is an, as yet, unidentied learning curve for its use that
requires learning curve data generation.
BRAIN MAPPING FOR LESIONS IN PRIMARY MOTOR CORTEX:
INTEGRATED SURGICAL APPROACH
JoséLavrador1, PrajwalGhimire1, ChristianBrogna1, LucianoFurlanetti1,
SabinaPatel1, RichardGullan1, KeyoumarsAshkan1, RanjeevBhangoo1,
FrancescoVergani1; 1King’s College Hospital Foundation Trust, United
Kingdom
BACKGROUND: Lesions within the corticospinal tract (CST) represent
signicant surgical challenge with a delicate functional trade-off that should
be integrated in the overall patient-centred treatment plan. METHODS: Pa-
tients with lesions within the CST with preoperative cortical and subcor-
tical mapping (nTMS and tractography), intraoperative mapping and
intraoperative provisional histological information (smear +- 5-ALA) were
included. This independently acquired information was integrated in a
decision-making process model to determine the intraoperative extent of
resection. RESULTS: 10 patients (6 patients with metastatic precentral tu-
mour; 1 patient with Grade III and 2 patients with grade IV gliomas; 1
patient with precentral vascular malformation) were included in the study.
Majority of the patient had pre-operative motor decit (60%). 50% pa-
tients underwent gross total resection and 40% patients underwent near
total resection of the lesions. In only one patient, no surgical resection was
possible after both pre-operative and intraoperative mapping. 70% of pa-
tients remained stable postoperatively and 20% improved from previous
motor weakness. CONCLUSION: The independently acquired anatomical
(anatomical MRI) and functional (nTMS and tractography) in patients with
CST lesions provide a more accurate guide for resection. The inclusion of
the histological information (smear +- 5-ALA) further allows the surgical
team to balance the potential functional risks within the global treatment
plan. Therefore, the patient is kept at the centre of the informed decision
making process.
COMBINED EXTRADURAL-INTERDURAL-INTRADURAL
APPROACH TO A TRIGEMINAL NERVE CYSTIC
HAEMANGIOPERICYTOMA WITH INTRA-OPERATIVE CRANIAL
NERVE MONITORING
JosephFrantzias1, JoséLavrador1, NoémiaPereira2, RichardGullan1,
KeyoumarsAshkan1, FrancescoVergani1, RanjeevBhangoo1,
NickThomas1; 1King’s College Hospital Foundation Trust, United
Kingdom, 2INOMED, United Kingdom
OBJECTIVES: Haemangiopericytoma of the trigemimal nerve is ex-
tremely rare, with only two previous cases described to our knowledge.
We present the surgical approach to this tumour, and describe a previously
poorly reported method of monitoring the function of the branches of the
trigeminal nerve: mapping of the sensory roots through transcranial somato-
sensory cortex sensory evoked potentials (SSEPs), motor evoked potentials
(MEP) for the motor root and blink reex. DESIGN: Case and technical
reports SUBJECTS: 32year-old male patient presenting with headaches and
vomiting, found to have a mixed cystic-solid tumour of the left middle skull
base region, in close relation with the foramen ovale and Meckel’s cave.
METHODS: The radiological features of the tumour, technical aspects of
the technical approach and neurophysiologic monitoring will be described.
RESULTS: A pterional craniotomy with fronto-temporal extradural-
interdural-intradural approach, and the tumour was debulked with MEP,
SSEP and blink reex monitoring of the branches of the trigeminal nerve.
Complete tumour removal was achieved with no post-operative cranial
nerve decits.
The histopathology revealed a cystic haemangiopericytoma. CONCLU-
SIONS: Haemangiopericytoma is a rare entity. MEP and SSEP monitoring
of the trigeminal nerve can be used to achieve complete and safe removal
of the tumour.
GRADE III MENINGIOMA: 10YEAR SINGLE CENTRE CASE SERIES
HariMcgrath1, JoseLavrador2, IoannisChristodoulides2,
PrajwalGhimire2, RichardGullan2, RanjeevBhangoo2,
KeyoumarsAshkan1,2, FrancescoVergani2; 1King’s College London,
London, United Kingdom, 2King’s College Hospital, London, United
Kingdom
RATIONALE: WHO Grade 3 meningiomas are a rare, malignant sub-
type of meningioma. Few controlled case series detailing its treatment and
follow-up are to be found in the literature. METHODS: Retrospective co-
hort study of patients treated in a single neuro-oncology centre in the period
between September 2008 and March 2019 with an initial diagnosis of WHO
Grade 3 meningioma. Demographic and clinical data has been collected
from the available medical records. RESULTS: 9 patients were included in
this series: 2 had convexity, 2 sphenoid wing, 2 parafalcine, 1 parasagittal
with a further 3 multiple locations and 1 patient with parietal convexity
meningioma. 3 tumours displayed rhabdoid features, whilst 4 displayed pap-
illary features and a further 2 displayed epithelial structures. All patients
underwent surgical intervention: 5 patients had a subtotal resection with 3
having total resection. 3/4 of reported Simpson Grading was grade 2, whilst
the remaining 1/4 was grade 1.The extent of resection for 1 patient was un-
certain. Post surgically, 6 received adjuvant radiotherapy, 2 had no further
treatment and 1 received gamma knife therapy. No patient received chemo-
therapy. 5 patients saw no tumour recurrence at follow up appointments
(mean 50months). Within 2years of their respective surgical interventions,
4 patients died due to tumour recurrence and associated complications (3
patients). CONCLUSION: To establish a uniform approach to treatment
of patients with WHO Grade 3 meningiomas is challenging. Management
involves a patient-centred approach based on multidisciplinary meeting de-
cisions. Multicentre registries may allow further conclusions.
REDO-SURGERY FOR RECURRENT GLIOBLASTOMA: A10-YEAR
SINGLE-INSTITUTION SERIES
JoséLavrador1, PrajwalGhimire1, ShamiAcharya1, AngelaSwampillai2,
JenniferGlendenning3, LucyBrazil2, OmarAlsahib2, RichardGullan1,
FrancescoVergani1, RanjeevBhangoo1, KeyoumarsAshkan1; 1King’s
College Hospital Foundation Trust, United Kingdom, 2Department of
Oncology, King’s Health Partners, London, UK, United Kingdom, 3Kent
Oncology Centre, Maidstone and Tunbridge Wells NHS Trust, Maidstone,
United Kingdom
INTRODUCTION: Multiple surgeries for recurrent / progressive glio-
blastomas is a matter of debate within the neuro-oncology community re-
ecting the higher risk of complications and the limited adjuvant treatment
options for patients who recurred after initial treatment. Therefore it is cru-
cial to identify who may benet of a more aggressive approach and if the
neurosurgical practice has changed in the last years. METHODS: Single-
Neuro-Oncology Surgical Centre (1 neurosurgical and 2 medical neuro-
oncology units) retrospective cohort study of patients with more than
one surgery for intracranial Glioblastoma Multiforme (GBM). All patient
diagnised with GBM at the time of the rst surgery in the period between
2009–2018. Second surgery within 2-months time following initial biopsy
or surgical complication or prior to chemo-radiotherapy were excluded.
Demographic and clinical data was collected from the medical records. RE-
SULTS: 96 patients underwent second surgery (63 males, 33 females, mean
age of 52.6) met criteria for surgery at progression. At the time of the rst
surgery, the extent of resection (EOR) was: 15 biopsy, 17 subtotal rescetion
(STR) and 35 gross total resection (GTR) – 29 missing data. With regards
to the molecular markers, 26 were IDH mutant, 73 were MGMT methy-
lated. All of the patients recieved adjuvant chemoradiotherapy following the
STUPP protocol prior. CONCLUSION: Our data corresponds to the data in
the current literature. Further qualitative study will provide an insight into
the effectiveness and aggressive approach to the recurrent GBMs.
A PROFILE OF ARGININE METHYLTRANSFERASE RECEPTORS IN
TWO IMMORTAL GLIOBLASTOMA CELL LINES: THE PRECURSOR
TO A NOVEL TARGET?
SrihariDeepak1, MissSabrinaSamuel2, JohnGreenman1,2,
ShailendraAchawal3, PedroBeltran-Alvarez2; 1Hull York Medical School,
Hull, United Kingdom, 2University of Hull, Hull, United Kingdom,
3Department of Neurosurgery, Hull Royal Inrmary, Hull, United Kingdom
BACKGROUND: Glioblastoma is a deadly disease with a median survival
of 15months after treatment. While maximal safe surgical resection and ad-
juvant chemoradiotherapy continues to be the mainstay of treatment, glio-
blastoma demostrates a remarkably heterogeneous molecular prole, and
there is a drive to discover further chemotherapeutic targets that can effectively
augment current multimodal therapy. INTRODUCTION: Post-translational
modication of proteins plays a key role in maintenance of regulatory cell
networks, and protein arginine methyltransferases (PRMT) are one of the en-
zymes involved in symmetric and asymmetric methylation of various proteins.
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