scholarly journals The Relationship Between Stimulation Current and Functional Site Localization During Brain Mapping

Neurosurgery ◽  
2020 ◽  
Author(s):  
Rachel H Muster ◽  
Jacob S Young ◽  
Peter Y M Woo ◽  
Ramin A Morshed ◽  
Gayathri Warrier ◽  
...  

Abstract BACKGROUND Gliomas are often in close proximity to functional regions of the brain; therefore, electrocortical stimulation (ECS) mapping is a common technique utilized during glioma resection to identify functional areas. Stimulation-induced seizure (SIS) remains the most common reason for aborted procedures. Few studies have focused on oncological factors impacting cortical stimulation thresholds. OBJECTIVE To examine oncological factors thought to impact stimulation threshold in order to understand whether a linear relationship exists between stimulation current and number of functional cortical sites identified. METHODS We retrospectively reviewed single-institution prospectively collected brain mapping data of patients with dominant hemisphere gliomas. Comparisons of stimulation threshold were made using t-tests and ANOVAs. Associations between oncologic factors and stimulation threshold were made using multivariate regressions. The association between stimulation current and number of positive sites was made using a Poisson model. RESULTS Of the 586 patients included in the study, SIS occurred in 3.92% and the rate of SIS events differed by cortical location (frontal 8.5%, insular 1.6%, parietal 1.3%, and temporal 2.8%; P = .009). Stimulation current was lower when mapping frontal cortex (P = .002). Stimulation current was not associated with tumor plus peritumor edema volume, world health organization) (WHO grade, histology, or isocitrate dehydrogenase (IDH) mutation status but was associated with tumor volume within the frontal lobe (P = .018). Stimulation current was not associated with number of positive sites identified during ECS mapping (P = .118). CONCLUSION SISs are rare but serious events during ECS mapping. SISs are most common when mapping the frontal lobe. Greater stimulation current is not associated with the identification of more cortical functional sites during glioma surgery.

Neurosurgery ◽  
2011 ◽  
Vol 69 (4) ◽  
pp. 852-863 ◽  
Author(s):  
Daniela Kuhnt ◽  
Oliver Ganslandt ◽  
Sven-Martin Schlaffer ◽  
Michael Buchfelder ◽  
Christopher Nimsky

Abstract BACKGROUND: The beneficial role of the extent of resection (EOR) in glioma surgery in correlation to increased survival remains controversial. However, common literature favors maximum EOR with preservation of neurological function, which is shown to be associated with a significantly improved outcome. OBJECTIVE: In order to obtain a maximum EOR, it was examined whether high-field intraoperative magnetic resonance imaging (iMRI) combined with multimodal navigation contributes to a significantly improved EOR in glioma surgery. METHODS: Two hundred ninety-three glioma patients underwent craniotomy and tumor resection with the aid of intraoperative 1.5 T MRI and integrated multimodal navigation. In cases of remnant tumor, an update of navigation was performed with intraoperative images. Tumor volume was quantified pre- and intraoperatively by segmentation of T2 abnormality in low-grade and contrast enhancement in high-grade gliomas. RESULTS: In 25.9% of all cases examined, additional tumor mass was removed as a result of iMRI. This led to complete tumor resection in 20 cases, increasing the rate of gross-total removal from 31.7% to 38.6%. In 56 patients, additional but incomplete resection was performed because of the close location to eloquent brain areas. Volumetric analysis showed a significantly (P < .01) reduced mean percentage of tumor volume following additional further resection after iMRI from 33.5% ± 25.1% to 14.7% ± 23.3% (World Health Organization [WHO] grade I, 32.8% ± 21.9% to 6.1% ± 18.8%; WHO grade II, 24.4% ± 25.1% to 10.8% ± 11.0%; WHO grade III, 35.1% ± 27.3% to 24.8% ± 26.3%; WHO grade IV, 34.2% ± 23.7% to 1.2% ± 16.2%). CONCLUSION: MRI in conjunction with multimodal navigation and an intraoperative updating procedure enlarges tumor-volume reduction in glioma surgery significantly without higher postoperative morbidity.


2018 ◽  
Vol 37 (02) ◽  
pp. 088-094
Author(s):  
Ricardo Ramina ◽  
Erasmo Silva Júnior ◽  
Felipe Constanzo ◽  
Maurício Coelho Neto

Introduction The improvement on the extent of resection (EOR) of gliomas with the combination of 5-aminolevulinic acid (5-ALA) and intraoperative magnetic resonance imaging (iMRI) has been demonstrated in previous studies. We present our results with the combined use of 5-ALA and (iMRI) in the surgery of glial lesions. Methods A total of 64 cases of patients with intracranial gliomas who underwent image-guided surgery using 5-ALA with and without (iMRI) were reviewed. All patients underwent an early postoperative MRI to evaluate the EOR. Other intra-operative techniques (awake surgery, electrophysiological stimulation and monitoring) were also performed according to the location of the tumor. Results A total of 18 tumors did not show intraoperative 5-ALA fluorescence (according to the World Health Organization [WHO] classification of tumors, 2 WHO-grade I, 14 WHO-grade II, 1 WHO-grade III and 1 WHO-grade IV), and 46 tumors showed intraoperative 5-ALA fluorescence (3 WHO-grade II, 3 WHO-grade III, 40 WHO-grade IV). In 28 of the 46 5-ALA positive cases, a safe 5-ALA free resection was achieved. In the 5-ALA negative cases, the (iMRI) findings guided the EOR, and complete resection was achieved in 11 cases. Complete resection was opted out in gliomas infiltrating eloquent areas. Conclusions The combined use of 5-ALA and IMRI showed improved results in glioma surgery, offering the safest maximal EOR. In the 5-ALA positive cases (mostly high-grade), fluorescence was a more useful tool. In the 5- ALA negative cases (mostly low-grade), the (iMRI) was decisive to guide the EOR of the tumor.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi240-vi241
Author(s):  
So Young Ji ◽  
Chae Eun Lee ◽  
Tamrin Chowdhury ◽  
Jin Wook Kim ◽  
Chul-Kee Park

Abstract Numerous studies reported a usefulness of 5-ALA fluorescence-guided surgery (FGS) in high grade gliomas. However, fluorescence pattern and intensity is variable among gliomas. In this study, we report our extensive experiences of FGS in various gliomas focusing on epidemiological data of fluorescence pattern. A total of 827 histologically proven glioma patients out of 900 brain tumor patients who had undergone FGS using 5-ALA during the period of 8.5 years between July 2010 and January 2019 were analyzed. Indication for FGS in glioma surgery harbored any evidence of possible high-grade foci at presumed gliomas in preoperative magnetic resonance images (MRI). Among the 827 gliomas, the number of cases corresponding to 2016 World Health Organization (WHO) grade IV, III, II, and I are 528 (58.7%), 193 (21.4%), 87 (9.7%) and 19 (2.1%), respectively. In terms of fluorescence rate, grade IV gliomas showed positive fluorescence in 95.4% of cases including strong intensity in 85.6%. Grade III gliomas showed fluorescence in about half of cases (55.0%), while 45.0% of cases did not show any fluorescence. Anaplastic oligodendroglioma had more positive rate (63.9%) than anaplastic astrocytoma (46.2%). Both grade II and I gliomas still showed positive fluorescence in about one-fourths of cases (24.1% and 26.3%, respectively). Among them ependymoma and pilocytic astrocytoma were fluorescence-prone tumors. This epidemiological data of 5-ALA fluorescence in various grades of gliomas provides fundamental reference to clinical application of FGS using 5-ALA in glioma surgery.


Author(s):  
Deepti Narasimhaiah ◽  
Bejoy Thomas ◽  
Mathew Abraham ◽  
Rajalakshmi Poyuran

AbstractDiffuse midline glioma, H3 K27M-mutant, is a World Health Organization (WHO) grade IV glioma arising in pons, thalamus, and spinal cord. They show mutations resulting in replacement of lysine at position 27 by methionine (K27M) of histone genes, H3F3A, HIST1H3B, and HIST1H3C. The H3 K27M mutant protein is identified in tumor tissue by immunohistochemistry. As these mutations are clonal and homogeneous, the mutant protein is normally identified in all tumor cells. Here we report a case of diffuse midline glioma with mosaic pattern of expression of H3 K27M mutant protein and discuss the diagnostic and therapeutic implications of this unusual pattern.


Author(s):  
Sima Sayyahmelli ◽  
Zhaoliang Sun ◽  
Emel Avci ◽  
Mustafa K. Başkaya

AbstractAnterior clinoidal meningiomas (ACMs) remain a major neurosurgical challenge. The skull base techniques, including extradural clinoidectomy and optic unroofing performed at the early stage of surgery, provide advantages for improving the extent of resection, and thereby enhancing overall outcome, and particularly visual function. Additionally, when the anterior clinoidal meningiomas encase neurovascular structures, particularly the supraclinoid internal carotid artery and its branches, this further increases morbidity and decreases the extent of resection. Although it might be possible to remove the tumor from the artery wall despite complete encasement or narrowing, the decision of whether the tumor can be safely separated from the arterial wall ultimately must be made intraoperatively.The patient is a 75-year-old woman with right-sided progressive vision loss. In the neurological examination, she only had light perception in the right eye without any visual acuity or peripheral loss in the left eye. MRI showed a homogeneously enhancing right-sided anterior clinoidal mass with encasing and narrowing of the supraclinoid internal carotid artery (ICA). Computed tomography (CT) angiography showed a mild narrowing of the right supraclinoid ICA with associated a 360-degree encasement. The decision was made to proceed using a pterional approach with extradural anterior clinoidectomy and optic unroofing. The surgery and postoperative course were uneventful. MRI confirmed gross total resection (Figs. 1 and 2). The histopathology was a meningothelial meningioma, World Health Organization (WHO) grade I. The patient continues to do well without any recurrence and has shown improved vision at 15-month follow-up.This video demonstrates important steps of the microsurgical skull base techniques for resection of these challenging tumors.The link to the video can be found at https://youtu.be/vt3o1c2o8Z0


Author(s):  
Sima Sayyahmelli ◽  
Emel Avci ◽  
Burak Ozaydin ◽  
Mustafa K. Başkaya

AbstractTrigeminal schwannomas are rare nerve sheet tumors that represent the second most common intracranial site of occurrence after vestibular nerve origins. Microsurgical resection of giant dumbbell-shaped trigeminal schwannomas often requires complex skull base approaches. The extradural transcavernous approach is effective for the resection of these giant tumors involving the cavernous sinus.The patient is a 72-year-old man with headache, dizziness, imbalance, and cognitive decline. Neurological examination revealed left-sided sixth nerve palsy, a diminished corneal reflex, and wasting of temporalis muscle. Magnetic resonance imaging (MRI) showed a giant homogeneously enhancing dumbbell-shaped extra-axial mass centered within the left cavernous sinus, Meckel's cave, and the petrous apex, with extension to the cerebellopontine angle. There was a significant mass effect on the brain stem causing hydrocephalus. Computed tomography (CT) scan showed erosion of the petrous apex resulting in partial anterior autopetrosectomy (Figs. 1 and 2).The decision was made to proceed with tumor resection using a transcavernous approach. Gross total resection was achieved. The surgery and postoperative course were uneventful, and the patient woke up the same as in the preoperative period. MRI confirmed gross total resection of the tumor. The histopathology was a trigeminal schwannoma, World Health Organization (WHO) grade I. The patient continues to do well without any recurrence at 15-month follow-up.This video demonstrates important steps of the microsurgical skull base techniques for resection of these challenging tumors.The link to the video can be found at https://youtu.be/TMK5363836M


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii46-ii46
Author(s):  
Jonathan Weller ◽  
Sophie Katzendobler ◽  
Philipp Karschnia ◽  
Stefanie Lietke ◽  
Rupert Egensperger ◽  
...  

Abstract BACKGROUND Current treatment guidelines for oligodendrogliomas (OD) recommend watch-and-wait strategies after gross total resection and radiation with subsequent chemotherapy (procarbazine, CCNU and vincristine (PCV)) after incomplete resection. The value of chemotherapy alone as an option to delay the risk of late cognitive deficits is not well defined yet. Here, we retrospectively investigated long-term outcome in OD WHO II with respect to initial therapy and tumor volume in magnetic resonance imaging (MRI). METHODS A total of 142 patients with OD WHO (World Health Organization) II according to WHO 2016 were retrospectively included. Patients either had watch and wait (W&W) after histological sampling through stereotactic biopsy (n=59) or tumor resection (n=27) or else stereotactic biopsy with subsequent temozolomide (TMZ) (n=26) or PCV (n=30). Pre- and post-therapeutic T2 tumor volumes were obtained. Progression-free survival (PFS), post-recurrence PFS (PR-PFS) and rate of secondary malignization after 10 years (MR-10yrs) were correlated with clinical and volumetric data. RESULTS PFS was significantly longer in the PCV cohort compared to TMZ (9.1 vs. 3.6 years, p = 0.04), even after matching patients according to age and initial tumor volume (9.1 vs 4.7 yrs, p = 0.03). PFS in the W&W cohort was 5.1 years and 4.4 years in those receiving tumor resection only. MR-10yrs was 4% in PCV cohort, 18% in the W&W cohort and 52% in the resection only cohort (p = 0.01). In the W&W cohort, patients treated with PCV at first relapse had a longer PR-PFS than those treated with TMZ (in years, 7.2 vs 4.0, p = 0.04). Multivariate analysis confirmed initial PCV therapy (p = 0.01) and initial T2 tumor volume (p = 0.02) to be prognostic. CONCLUSION In oligodendrogliomas WHO II PCV chemotherapy alone is superior in terms of PFS and rate of secondary malignization compared to TMZ chemotherapy alone or tumor resection only.


Author(s):  
Mizuho Inoue ◽  
Mohamed Labib ◽  
Alexander Yang ◽  
A. Samy Youssef

AbstractA case of a recurrent sphenocavernous meningioma is presented. The patient is a 42-year-old male who presented with an episode of transient right-sided numbness. A magnetic resonance imaging (MRI) revealed a large left sphenocavernous meningioma. The patient underwent a frontotemporal craniotomy for tumor resection. Near total resection was achieved with minimal residual in the left cavernous sinus (CS) and orbital apex. The pathology was consistent with meningioma, World Health Organization (WHO) grade I. A follow-up MRI was done 9 months after surgery and showed a growth of the residual tumor, which was treated with intensity modulated radiotherapy. Tumor growth was detected on serial imaging over a 4-year period. Surgical resection was offered. A left frontotemporal craniotomy with pretemporal transcavernous approach was performed. The bone flap was reopened and the dura was opened in a Y-shaped fashion. The roof of the optic canal was drilled off, and the falciform ligament was opened to decompress the optic nerve. The tumor was disconnected from the anterior clinoid region (the anterior clinoid process was eroded by the tumor) and reflected off the wall of the lateral CS. Tumor was adherent to the V2 fascicles (the lateral CS wall was resected in the first surgery) and was sharply dissected off. Gross total resection was achieved. The pathology was consistent with meningioma, WHO grade I. The patient had an unremarkable postoperative course without any new neurological deficits.The link to the video can be found at: https://youtu.be/KVBVw_86JqM.


BMC Neurology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Jessica Rossi ◽  
Lucia Giaccherini ◽  
Francesco Cavallieri ◽  
Manuela Napoli ◽  
Claudio Moratti ◽  
...  

Abstract Background Glioblastoma (GBM) is known for its devastating intracranial infiltration and its unfavorable prognosis, while extracranial involvement is a very rare event, more commonly attributed to IDH wild-type (primary) GBM evolution. Case presentation We present a case of a young woman with a World Health Organization (WHO) grade II Astrocytoma evolved to WHO grade IV IDH mutant glioblastoma, with subsequent development of lymphatic and bone metastases, despite the favorable biomolecular pattern and the stability of the primary brain lesion. Conclusions Our case highlights that grade II Astrocytoma may evolve to a GBM and rarely lead to a secondary metastatic diffusion, which can progress quite rapidly; any symptoms referable to a possible systemic involvement should be carefully investigated.


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