Commentary: Novel Use of Stimulating Fence-Post Technique for Functional Mapping of Subcortical White Matter During Tumor Resection: A Technical Case Series

Abstract Background Maximal safe resection remains a key principle in infiltrating glioma management. Stimulation mapping is a key adjunct for minimizing functional morbidity while “fence-post” procedures use catheters or dye to mark the tumor border at the start of the procedure prior to brain shift. Objective To report a novel technique using stereotactically placed electrodes to guide tumor resection near critical descending subcortical fibers. Methods Navigated electrodes were placed prior to tumor resection along the deep margin bordering presumed eloquent tracts. Stimulation was administered through these depth electrodes for subcortical motor and language mapping. Results Twelve patients were included in this preliminary technical report. Seven patients (7/12, 58%) were in asleep cases, while the other 5 cases (5/12, 42%) were performed awake. Mapping of motor fibers was performed in 8 cases, and language mapping was done in 1 case. In 3 cases, both motor and language mapping were performed using the same depth electrode spanning corticospinal tract and the arcuate fasciculus. Conclusion Stereotactic depth electrode placement coupled with stimulation mapping of white matter tracts can be used concomitantly to demarcate the border between deep tumor margins and eloquent brain, thus helping to maximize extent of resection while minimizing functional morbidity.

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Receptor tyrosine kinase gene amplification is predictive of intraoperative seizures during glioma resection with functional mapping

Journal of Neurosurgery ◽

10.3171/2018.12.jns182700 ◽

2020 ◽

Vol 132 (4) ◽

pp. 1017-1023 ◽

Cited By ~ 2

Author(s):

Bryan D. Choi ◽

Daniel K. Lee ◽

Jimmy C. Yang ◽

Caroline M. Ayinon ◽

Christine K. Lee ◽

...

Keyword(s):

Tyrosine Kinases ◽

Univariate Analysis ◽

Tumor Resection ◽

Tumor Grade ◽

Molecular Data ◽

Genetic Alterations ◽

Functional Mapping ◽

Chi Square ◽

Kinase Gene ◽

Glioma Resection

OBJECTIVEIntraoperative seizures during craniotomy with functional mapping is a common complication that impedes optimal tumor resection and results in significant morbidity. The relationship between genetic mutations in gliomas and the incidence of intraoperative seizures has not been well characterized. Here, the authors performed a retrospective study of patients treated at their institution over the last 12 years to determine whether molecular data can be used to predict the incidence of this complication.METHODSThe authors queried their institutional database for patients with brain tumors who underwent resection with intraoperative functional mapping between 2005 and 2017. Basic clinicopathological characteristics, including the status of the following genes, were recorded: IDH1/2, PIK3CA, BRAF, KRAS, AKT1, EGFR, PDGFRA, MET, MGMT, and 1p/19q. Relationships between gene alterations and intraoperative seizures were evaluated using chi-square and two-sample t-test univariate analysis. When considering multiple predictive factors, a logistic multivariate approach was taken.RESULTSOverall, 416 patients met criteria for inclusion; of these patients, 98 (24%) experienced an intraoperative seizure. Patients with a history of preoperative seizure and those treated with antiepileptic drugs prior to surgery were less likely to have intraoperative seizures (history: OR 0.61 [95% CI 0.38–0.96], chi-square = 4.65, p = 0.03; AED load: OR 0.46 [95% CI 0.26–0.80], chi-square = 7.64, p = 0.01). In a univariate analysis of genetic markers, amplification of genes encoding receptor tyrosine kinases (RTKs) was specifically identified as a positive predictor of seizures (OR 5.47 [95% CI 1.22–24.47], chi-square = 5.98, p = 0.01). In multivariate analyses considering RTK status, AED use, and either 2007 WHO tumor grade or modern 2016 WHO tumor groups, the authors found that amplification of the RTK proto-oncogene, MET, was most predictive of intraoperative seizure (p < 0.05).CONCLUSIONSThis study describes a previously unreported association between genetic alterations in RTKs and the occurrence of intraoperative seizures during glioma resection with functional mapping. Future models estimating intraoperative seizure risk may be enhanced by inclusion of genetic criteria.

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High Resolution Diffusion Tensor Imaging of Cortical-Subcortical White Matter Tracts in TBI

10.21236/ada549548 ◽

2010 ◽

Author(s):

Deborah M. Little

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

High Resolution ◽

Diffusion Tensor ◽

Subcortical White Matter ◽

White Matter Tracts

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What Has Direct Cortical and Subcortical Electrostimulation Taught Us about Neurolinguistics?

The Oxford Handbook of Neurolinguistics ◽

10.1093/oxfordhb/9780190672027.013.8 ◽

2019 ◽

pp. 185-211

Author(s):

Hugues Duffau

Keyword(s):

White Matter ◽

Large Scale ◽

Functional Neuroimaging ◽

Great Accuracy ◽

Subcortical White Matter ◽

Cerebral Lesions ◽

Physiological Basis ◽

Postoperative Mri ◽

The Brain

Investigating the neural and physiological basis of language is one of the most important challenges in neurosciences. Direct electrical stimulation (DES), usually performed in awake patients during surgery for cerebral lesions, is a reliable tool for detecting both cortical and subcortical (white matter and deep grey nuclei) regions crucial for cognitive functions, especially language. DES transiently interacts locally with a small cortical or axonal site, but also nonlocally, as the focal perturbation will disrupt the entire subnetwork sustaining a given function. Thus, in contrast to functional neuroimaging, DES represents a unique opportunity to identify with great accuracy and reproducibility, in vivo in humans, the structures that are actually indispensable to the function, by inducing a transient virtual lesion based on the inhibition of a subcircuit lasting a few seconds. Currently, this is the sole technique that is able to directly investigate the functional role of white matter tracts in humans. Thus, combining transient disturbances elicited by DES with the anatomical data provided by pre- and postoperative MRI enables to achieve reliable anatomo-functional correlations, supporting a network organization of the brain, and leading to the reappraisal of models of language representation. Finally, combining serial peri-operative functional neuroimaging and online intraoperative DES allows the study of mechanisms underlying neuroplasticity. This chapter critically reviews the basic principles of DES, its advantages and limitations, and what DES can reveal about the neural foundations of language, that is, the large-scale distribution of language areas in the brain, their connectivity, and their ability to reorganize.

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Primary Calvarial Ewing Sarcoma: A Case Series

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0041-1722900 ◽

2021 ◽

Author(s):

Sandeep Mohindra ◽

Manjul Tripathi ◽

Aman Batish ◽

Ankur Kapoor ◽

Ninad Ramesh Patil ◽

...

Keyword(s):

Ewing Sarcoma ◽

Tumor Resection ◽

Case Series ◽

Radical Excision ◽

Term Outcome ◽

Long Term Outcome ◽

Intradural Tumor ◽

Age Range

Abstract Background Calvarial Ewing tumor is a relatively rare differential among bony neoplasms. We present our experience of managing primary calvarial Ewing sarcoma (EWS), highlighting their clinical and radiological findings. Method In a retrospective analysis, we evaluated our 12-year database for pathologically proven EWS. A literature search was conducted for the comparative presentation and update on the management and outcome. Result From January 2008 to December 2020, we managed eight patients (male:female = 5:3; age range 6 months to 19 years, mean 11.5 years) harboring primary calvarial EWS. All cases underwent wide local excision; two patients required intradural tumor resection, while one required rotation flap for scalp reconstruction. Mean hospital stay was 8 days. All patients received adjuvant chemo- and radiotherapy. Three patients remained asymptomatic at 5 years of follow-up, while two patients died. Conclusion Primary calvarial EWS is a rare entity. It usually affects patients in the first two decades of life. These tumors can be purely intracranial, causing raised intracranial pressure symptoms, which may exhibit rapidly enlarging subgaleal tumors with only cosmetic deformities or symptoms of both. Radical excision followed by adjuvant therapy may offer a favorable long-term outcome.

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Preliminary Evidence for a Relationship between Elevated Plasma TNFα and Smaller Subcortical White Matter Volume in HCV Infection Irrespective of HIV or AUD Comorbidity

International Journal of Molecular Sciences ◽

10.3390/ijms22094953 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4953

Author(s):

Natalie M. Zahr ◽

Kilian M. Pohl ◽

Allison J. Kwong ◽

Edith V. Sullivan ◽

Adolf Pfefferbaum

Keyword(s):

White Matter ◽

Proinflammatory Cytokines ◽

Soluble Protein ◽

Subcortical White Matter ◽

Control Group ◽

White Matter Volume ◽

Brain Volumes ◽

Protein Levels ◽

Matter Volume ◽

Patient Groups

Classical inflammation in response to bacterial, parasitic, or viral infections such as HIV includes local recruitment of neutrophils and macrophages and the production of proinflammatory cytokines and chemokines. Proposed biomarkers of organ integrity in Alcohol Use Disorders (AUD) include elevations in peripheral plasma levels of proinflammatory proteins. In testing this proposal, previous work included a group of human immunodeficiency virus (HIV)-infected individuals as positive controls and identified elevations in the soluble proteins TNFα and IP10; these cytokines were only elevated in AUD individuals seropositive for hepatitis C infection (HCV). The current observational, cross-sectional study evaluated whether higher levels of these proinflammatory cytokines would be associated with compromised brain integrity. Soluble protein levels were quantified in 86 healthy controls, 132 individuals with AUD, 54 individuals seropositive for HIV, and 49 individuals with AUD and HIV. Among the patient groups, HCV was present in 24 of the individuals with AUD, 13 individuals with HIV, and 20 of the individuals in the comorbid AUD and HIV group. Soluble protein levels were correlated to regional brain volumes as quantified with structural magnetic resonance imaging (MRI). In addition to higher levels of TNFα and IP10 in the 2 HIV groups and the HCV-seropositive AUD group, this study identified lower levels of IL1β in the 3 patient groups relative to the control group. Only TNFα, however, showed a relationship with brain integrity: in HCV or HIV infection, higher peripheral levels of TNFα correlated with smaller subcortical white matter volume. These preliminary results highlight the privileged status of TNFα on brain integrity in the context of infection.

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Diffusion tensor imaging analysis in scrub typhus meningoencephalitis to determine the alteration of microstructural subcortical white-matter integrity

The Neuroradiology Journal ◽

10.1177/1971400920980311 ◽

2020 ◽

pp. 197140092098031

Author(s):

Pranjal Phukan ◽

Kalyan Sarma ◽

Aman Yusuf Khan ◽

Bhupen Barman ◽

Md Jamil ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Scrub Typhus ◽

Diffusion Tensor ◽

Neuronal Degeneration ◽

Central Nervous System Involvement ◽

Subcortical White Matter ◽

White Matter Integrity ◽

Conventional Mri ◽

Significant Difference

Background and purpose Magnetic resonance imaging (MRI) of the brain in scrub typhus meningoencephalitis is non-specific, and in the majority of the cases, conventional MRI fails to detect any abnormality. However, autopsy reports depict central nervous system involvement in almost all patients. There is therefore a need for research on the quantitative assessment of brain parenchyma that can detect microstructural abnormalities. The study aimed to assess the microstructural integrity changes of scrub typhus meningoencephalitis by using different diffusion tensor imaging (DTI) parameters. Methods This was a retrospective analysis of scrub typhus meningoencephalitis. Seven patients and seven age- and sex-matched healthy controls were included. Different DTI parameters such as apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative anisotropy (RA), trace, volume ratio (VR) and geodesic anisotropy (GA) were obtained from six different regions of subcortical white matter at the level of the centrum semiovale. Intergroup significant difference was determined by one-way analysis of variance followed by Tukey’s post hoc test. Receiver operating characteristic curves were constructed to determine the accuracy of the DTI matrices. Results There was a significant decrease in FA, RA and GA as well as an increase in ADC and VR in the subcortical white matter in patients with scrub typhus meningoencephalitis compared to controls ( p < 0.001). The maximum sensitivity of the DTI parameters was 85.7%, and the maximum specificity was 81%. Conclusion There was an alteration of subcortical white-matter integrity in scrub typhus meningoencephalitis that represents the axonal degeneration, myelin breakdown and neuronal degeneration. DTI may be a useful tool to detect white-matter abnormalities in scrub typhus meningoencephalitis in clinical practice, particularly in patients with negative conventional MRI.

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The Role of Visceral Transplantation for Neoplastic Disease

Digestive Disease Interventions ◽

10.1055/s-0040-1715810 ◽

2020 ◽

Vol 04 (03) ◽

pp. 273-281

Author(s):

Masato Fujiki ◽

Amit Nair ◽

Giuseppe D'amico ◽

Mohammed Osman

Keyword(s):

Patient Survival ◽

Ex Vivo ◽

Tumor Resection ◽

Case Series ◽

National Database ◽

Neuroendocrine Neoplasms ◽

Neoplastic Disease ◽

Desmoid Tumors ◽

Post Transplant ◽

Recipient Tissue

AbstractVisceral transplantation has been utilized as the most radical surgical treatment for neoplasms not amenable to conventional resection. The main indications for this procedure include mesenteric desmoid tumors threatening the root of mesentery and metastatic neuroendocrine neoplasms. Published case-series of visceral transplantation for such indications are reviewed in this article. Patients with desmoid tumors associated with familial adenomatous polyposis are transplanted with intestinal or multivisceral allografts. With surgical modification of technique, the native spleen is preserved while duodenopancreatic complex is removed to obviate the risk of malignant transformation of duodenal polyposis after transplantation. Preservation of spleen decreased incidence of post-transplant lymphoproliferative disorder, conferring therapeutic advantage. Patient survival is comparable to that of other indications, and desmoid tumor recurrence has been observed in the recipient tissue but not in the donor allograft. For visceral transplantation of metastatic neuroendocrine neoplasms, the majority of these patients have diffuse liver involvement, thus requiring full multivisceral transplantation. Post-transplant patient survival is acceptable with limited data available on recurrence. Autotransplantation following ex vivo tumor resection using visceral allografts has been also performed in a limited, select cohort of patients with various pathologies. Adenocarcinomas are associated with a prohibitive recurrence rate following the procedure, and its use for this indication is therefore not recommended. A national database of visceral transplantation undertaken for neoplastic disease should be developed to better understand predictors of outcomes and to help produce and standardize selection criteria.

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Complex Bone Tumors of the Trunk—The Role of 3D Printing and Navigation in Tumor Orthopedics: A Case Series and Review of the Literature

Journal of Personalized Medicine ◽

10.3390/jpm11060517 ◽

2021 ◽

Vol 11 (6) ◽

pp. 517

Author(s):

Martin Schulze ◽

Georg Gosheger ◽

Sebastian Bockholt ◽

Marieke De Vaal ◽

Tymo Budny ◽

...

Keyword(s):

3D Printing ◽

Tumor Resection ◽

Case Series ◽

Main Process ◽

Patient Centered ◽

Individual Care ◽

Real Time Visualization ◽

Bone Tumor Resection ◽

Virtual Modeling

The combination of 3D printing and navigation promises improvements in surgical procedures and outcomes for complex bone tumor resection of the trunk, but its features have rarely been described in the literature. Five patients with trunk tumors were surgically treated in our institution using a combination of 3D printing and navigation. The main process includes segmentation, virtual modeling and build preparation, as well as quality assessment. Tumor resection was performed with navigated instruments. Preoperative planning supported clear margin multiplanar resections with intraoperatively adaptable real-time visualization of navigated instruments. The follow-up ranged from 2–15 months with a good functional result. The present results and the review of the current literature reflect the trend and the diverse applications of 3D printing in the medical field. 3D printing at hospital sites is often not standardized, but regulatory aspects may serve as disincentives. However, 3D printing has an increasing impact on precision medicine, and we are convinced that our process represents a valuable contribution in the context of patient-centered individual care.

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Magnetic resonance imaging findings in children with Parry-Romberg syndrome and en coup de sabre

Pediatric Rheumatology ◽

10.1186/s12969-021-00512-6 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Harry Knights ◽

Elizabeth Minas ◽

Faraan Khan ◽

Lindsay Shaw ◽

Muthana Al Obaidi ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

White Matter ◽

Magnetic Resonance ◽

Brain Imaging ◽

Case Series ◽

Dystrophic Calcification ◽

Resonance Imaging ◽

Cutaneous Manifestations ◽

Street Hospital ◽

Parry Romberg Syndrome

Abstract Background The aim of this study was to: (i) describe the abnormalities seen on brain imaging in a group of children with en coup de sabre (EDCS) with/without Parry-Romberg syndrome (PRS); and (ii) identify clinical predictors of brain imaging abnormalities. Methods This was a single centre (Great Ormond Street Hospital, London) retrospective case series of patients with ECDS/PRS seen from 2000 to 2018. We identified patients with cutaneous manifestations consistent with the clinical descriptions of ECDS/PRS. Presenting clinical, laboratory, and radiological brain findings are described. Results are expressed as medians and ranges or frequencies and percentages. Fisher’s exact test was used to identify clinical associations with magnetic resonance imaging (MRI) abnormalities. Results Fourteen patients were studied: 6 males and 8 females; median age 14 years (range 3–20). We observed neuroimaging abnormalities in 2/6 ECDS and 5/8 ECDS/PRS patients. White matter signal abnormality, dystrophic calcification, leptomeningeal enhancement, and sulcal crowding were the typical findings on brain imaging. A total of 50% of patients had no MRI abnormality despite some of these patients having neurological symptoms. The presence of seizures was significantly associated with ipsilateral enhanced white matter signalling on MRI (p < 0.05). Conclusions In summary, we observed several distinct radiographic patterns associated with ECDS/PRS. Seizure disorder was strongly associated with the presence of ipsilateral enhanced white matter signalling. Improved neuroimaging techniques that combine morphological with functional imaging may improve the detection rate of brain involvement in children with ECDS/PRS in the future.

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