Permanent deterioration of fine motor skills after the resection of tumors in the supplementary motor area

Supplementary motor area syndrome (SMAS) represents a common neurosurgical sequela. The incidence and time frame of its occurrence have yet to be characterized after surgery for brain tumors. We examined patients suffering from a brain tumor preoperatively, postoperatively, and during follow-up examinations after three months, including fine motor skills testing and transcranial magnetic stimulation (TMS). 13 patients suffering from a tumor in the dorsal part of the superior frontal gyrus underwent preoperative, early postoperative, and 3-month follow-up testing of fine motor skills using the Jebsen-Taylor Hand Function Test (JHFT) and the Nine-Hole Peg Test (NHPT) consisting of 8 subtests for both upper extremities. They completed TMS for cortical motor function mapping. Test completion times (TCTs) were recorded and compared. No patient suffered from neurological deficits before surgery. On postoperative day one, we detected motor deficits in two patients, which remained clinically stable at a 3-month follow-up. Except for page-turning, every subtest indicated a significant worsening of function, reflected by longer TCTs (p < 0.05) in the postoperative examinations for the contralateral upper extremity (contralateral to the tumor manifestation). At 3-month follow-up examinations for the contralateral upper extremity, each subtest indicated significant worsening compared to the preoperative status despite improvement to the immediate postoperative level. We also detected significantly longer TCTs (p < 0.05) postoperatively in the ipsilateral upper extremity. This study suggests a long-term worsening of fine motor skills even three months after SMA tumor resection, indicating the necessity of targeted physical therapy for these patients.

The role of molecular tumor boards in neuro-oncology: a nationwide survey

BACKGROUND

In neuro-oncology, the inclusion of tumor patients in the molecular tumor board has only become increasingly widespread in recent years, but so far there are no standards for indication, procedure, evaluation, therapy recommendations and therapy implementation of neuro-oncological patients. The present work examines the current handling of neuro-oncological patients included in molecular tumor boards in Germany.

METHODS

We created an online based survey with questions covering the handling of neuro-oncologic patient inclusion, annotation of genetic analyses, management of target therapies and the general role of molecular tumor boards in neuro-oncology in Germany. We contacted all members of the Neuro-Oncology working group (NOA) of the German Cancer Society (DKG) by e-mail.

RESULTS

38 responses were collected. The majority of those who responded were specialists in neurosurgery or neurology with more than 10 years of professional experience working at a university hospital. Molecular tumor boards (MTB) regularly take place once a week and all treatment disciplines of neuro-oncology patients take part. The inclusions to the MTB are according to distinct tumors and predominantly in case of tumor recurrence. An independently MTB member mostly create the recommendations, which are regularly implemented in the tumor treatment. Recommendations are given for alteration classes 4 and 5. Problems exist mostly within the cost takeover of experimental therapies. The experimental therapies are mostly given in the department of medical oncology.

CONCLUSIONS

Molecular tumor boards for neuro-oncological patients, by now, are not standardized in Germany. Similarities exists for patient inclusion and interpretation of molecular alterations; the time point of inclusion and implementation during the patient treatment differ between the various hospitals. Further studies for standardization and harmonisation are needed. In summary, most of the interviewees envision great opportunities and possibilities for molecular-based neuro-oncological therapy in the future.

Neurological Outcome and Respiratory Insufficiency in Intramedullary Tumors of the Upper Cervical Spine

Background and Objectives: Intramedullary spinal cord tumors (IMSCT) are rare entities. A location in the upper cervical spine as a highly eloquent region carries the risk of postoperative neurological deficits, such as tetraparesis or respiratory dysfunction. Evidence for respiratory dysfunction is scarce. This study aimed to describe these highly eloquent tumors' early and late postoperative clinical course. Materials and Methods: This is a single-center retrospective cohort study. We included 35 patients with IMSCT at levels of the craniocervical junction to C4 who underwent surgical treatment between 2008 and 2022. The authors analyzed the patients' preoperative status, tumor- and surgery-specific characteristics, and follow-up functional status. Results: The study cohort included twenty-two patients with grade II ependymoma (62.9%), two low-grade astrocytomas (5.7%), two glioblastomas (5.7%), six hemangioblastomas (17.1%), two metastases (5.7%), and one patient with partially intramedullary schwannoma (2.9%). Gross total resection was achieved in 76% of patients. Early dorsal column-related symptoms (gait ataxia and sensory loss) and motor deterioration occurred in 64% and 44% of patients. At a follow-up of 3.27 ± 3.83 years, 43% and 33% of patients still exhibited postoperative sensory and motor deterioration, respectively. The median McCormick Scale grade was 2 in the preoperative and late postoperative periods, respectively. Only three patients (8.6%) developed respiratory dysfunction, of whom, two patients, both with malignant IMSCT, required prolonged invasive ventilation. Conclusions: More than 60% of the patients with IMSCT in the upper cervical cord developed new neurological deficits in the immediate postoperative period, and more than 40% are permanent. However, these deficits are not disabling in most cases since most patients maintain functional independence as observed by unchanged low McCormick scores. The rate of respiratory insufficiency is relatively low and seems to be influenced by the rapid neurological deterioration in high-grade tumors.

A rare case of H3K27-altered diffuse midline glioma with multiple osseous and spinal metastases at the time of diagnosis

BACKGROUND

H3K27-altered diffuse midline gliomas are uncommon central nervous system tumors with extremely poor prognoses.

CASE PRESENTATION

We report the case of a 24-year-old man patient with multiple, inter alia osseous metastases who presented with back pain, hemi-hypoesthesia, and hemi-hyperhidrosis. The patient underwent combined radio-chemotherapy and demonstrated temporary improvement before deteriorating.

CONCLUSIONS

H3K27-altered diffuse midline glioma presents an infrequent but crucial differential diagnosis and should be considered in cases with rapid neurological deterioration and multiple intracranial and intramedullary tumor lesions in children and young adults. Combined radio-chemotherapy delayed the neurological deterioration, but unfortunately, progression occurred three months after the diagnosis.

Preoperative angiographic considerations and neurological outcome after surgical treatment of intradural spinal hemangioblastoma: a multicenter retrospective case series

PURPOSE

Intradural spinal hemangioblastomas are rare highly hypervascularized benign neoplasms. Surgical resection remains the treatment of choice, with a significant risk of postoperative neurological deterioration. Due to the tumor infrequency, scientific evidence is scarce and limited to case reports and small case series.

METHODS

We performed a retrospective multicenter study including five high-volume neurosurgical centers analyzing patients surgically treated for spinal hemangioblastomas between 2006 and 2021. We assessed clinical status, surgical data, preoperative angiograms, and embolization when available. Follow-up records were analyzed, and logistic regression performed to assess possible risk factors for neurological deterioration.

RESULTS

We included 60 patients in Germany and Austria. Preoperative angiography was performed in 30% of the cases; 10% of the patients underwent preoperative embolization. Posterior tumor location and presence of a syrinx favored gross total tumor resection (93.8% vs. 83.3% and 97.1% vs. 84%). Preoperative embolization was not associated with postoperative worsening. The clinical outcome revealed a transient postoperative neurological deterioration in 38.3%, depending on symptom duration and preoperative modified McCormick grading, but patients recovered in most cases until follow-up.

CONCLUSION

Spinal hemangioblastoma patients significantly benefit from early surgical treatment with only transient postoperative deterioration and complete recovery until follow-up. The performance of preoperative angiograms remains subject to center disparities.

Digital cognitive testing using a tablet-based app in patients with brain tumors: a single-center feasibility study comparing the app to the gold standard

OBJECTIVE

Healthcare digitization has led to increasing tablet-based apps to improve diagnostics, self-discipline, and well-being in patients. Moreover, patient-reported outcome measures are crucial for optimized treatment, with superior applicability if independent from patient visits. Whereas most uses cover health maintenance, only a few studies have focused on cognitive testing in neurosurgical patients despite its nature as one of the most integrative outcome measures in neurooncology.

METHODS

The authors performed a prospective single-center feasibility study including neurosurgical patients affected by intraaxial tumors and healthy subjects, testing cognitive function by using a digitized app-based approach and conventional paper-and-pencil (PP) tests. Healthy subjects underwent follow-up testing for retest reliability.

RESULTS

The authors included 24 patients with brain tumor and 10 healthy subjects, all of whom completed both tests. Equivalent mean performance results were found in the tablet-based digital app and PP counterparts; whereas the digital approach had shorter test duration in patients (29.9 minutes for PP vs 21.9 minutes for app, p = 0.019) and in the healthy cohort (23.2 minutes for PP vs 16.4 minutes for app, p = 0.003), patients with brain tumor scored lower when both test strategies were applied. Results were consistent in healthy subjects after a median of 3 months.

CONCLUSIONS

Cognitive function assessment is feasible using a digitized tablet-based app, with equivalent results to those of PP tests in healthy subjects and patients with brain tumor. Thus, this approach allows much closer follow-up independent of patient visits and might provide a viable option to improve patient follow-ups.

Quality of life and return to work and sports after spinal ependymoma resection

Adult spinal ependymoma presents a rare low-grade tumor entity. Due to its incidence peak in the fourth decade of life, it mostly affects patients during a professionally and physically active time of life. We performed a retrospective monocentric study, including all patients operated upon for spinal ependymoma between 2009 and 2020. We prospectively collected data on professional reintegration, physical activities and quality-of-life parameters using EQ-5D and SF-36. Issues encountered were assessed using existing spinal-cord-specific questionnaires and free-text questions. In total, 65 of 114 patients agreed to participate. Most patients suffered from only mild pre- and postoperative impairment on the modified McCormick scale, but 67% confirmed difficulties performing physical activities in which they previously engaged due to pain, coordination problems and fear of injuries after a median follow-up of 5.4 years. We observed a shift from full- to part-time employment and patients unable to work, independently from tumor dignity, age and neurological function. Despite its benign nature and occurrence of formal only mild neurological deficits, patients described severe difficulties returning to their preoperative physical activity and profession. Clinical scores such as the McCormick grade and muscle strength may not reflect the entire self-perceived impairment appropriately.

A multicenter cohort study of early complications after cranioplasty: results of the German Cranial Reconstruction Registry

OBJECTIVE

Cranioplasty (CP) is a crucial procedure after decompressive craniectomy and has a significant impact on neurological improvement. Although CP is considered a standard neurosurgical procedure, inconsistent data on surgery-related complications after CP are available. To address this topic, the authors analyzed 502 patients in a prospective multicenter database (German Cranial Reconstruction Registry) with regard to early surgery-related complications.

METHODS

Early complications within 30 days, medical history, mortality rates, and neurological outcome at discharge according to the modified Rankin Scale (mRS) were evaluated. The primary endpoint was death or surgical revision within the first 30 days after CP. Independent factors for the occurrence of complications with or without surgical revision were identified using a logistic regression model.

RESULTS

Traumatic brain injury (TBI) and ischemic stroke were the most common underlying diagnoses that required CP. In 230 patients (45.8%), an autologous bone flap was utilized for CP; the most common engineered materials were titanium (80 patients [15.9%]), polyetheretherketone (57 [11.4%]), and polymethylmethacrylate (57 [11.4%]). Surgical revision was necessary in 45 patients (9.0%), and the overall mortality rate was 0.8% (4 patients). The cause of death was related to ischemia in 2 patients, diffuse intraparenchymal hemorrhage in 1 patient, and cardiac complications in 1 patient. The most frequent causes of surgical revision were epidural hematoma (40.0% of all revisions), new hydrocephalus (22.0%), and subdural hematoma (13.3%). Preoperatively increased mRS score (OR 1.46, 95% CI 1.08-1.97, p = 0.014) and American Society of Anesthesiologists Physical Status Classification System score (OR 2.89, 95% CI 1.42-5.89, p = 0.003) were independent predictors of surgical revision. Ischemic stroke, as the underlying diagnosis, was associated with a minor rate of revisions compared with TBI (OR 0.18, 95% CI 0.06-0.57, p = 0.004).

CONCLUSIONS

The authors have presented class II evidence-based data on surgery-related complications after CP and have identified specific preexisting risk factors. These results may provide additional guidance for optimized treatment of these patients.

Body mass index has an impact on preoperative symptoms but not clinical outcome in acute cauda equina syndrome

Cauda equina syndrome (CES) presents a surgical emergency with treatment required within 48 h. Symptoms include reduced saddle sensation, micturition difficulties, and/or anal sphincter impairment. Controversy exists regarding the effect on and coincidence of overweight with CES. We performed a retrospective case-control study of all patients treated surgically for acute complete and incomplete CES in our neurosurgical department from 2009 to 2020, focusing on the preoperative BMI and postoperative neurological outcome. In addition, we performed a comprehensive literature review. Fifty patients with CES were included, of whom 96% suffered from a decompensated lumbar spinal stenosis or disc prolapse between the L4/5 and L5/S1 levels. Our cohort population was overweight but not obese: mean BMI was 27.5 kg/m², compared with 27.6 kg/m² in patients with degenerative spine surgery. BMI did not significantly influence the postoperative outcome, but it did affect preoperative symptoms and surgery duration. Symptom duration significantly differed depending on the underlying cause for CES. The literature review revealed sparse evidence, with only four clinical case series presenting contradictory results. We provide a comprehensive literature review on the current evidence regarding CES and obesity and conclude that we did not observe an association between obesity and CES occurrence. Patients with CES and other degenerative spinal pathologies belong to an overweight but not obese population. Body Mass Index has an impact on preoperative symptoms but not clinical outcome in acute CES.

Single-centre study comparing surgically and conservatively treated patients with spinal cord herniation and review of the literature

Introduction

Spinal cord herniation (SCH) is a rare cause of progressive myelopathy and Brown-Séquard-Syndrome.

Research question

Evaluation of functional outcome after SCH treatment compared to conservatively treated patients.

Material and methods

We retrospectively analysed functional outcome in SCH patients treated between 2009 and 2020. We conducted a systematic search using PubMed, MEDLINE and EMBASE to perform a pooled analysis in SCH patients.

Results

Our hospital cohort included 17 patients of which 9 were treated surgically. Mean age was 51.9 years, 58.8% of the patients were female. In 4/9 patients (44.4%) the neurological state remained stable after surgery. Four patients improved (44.4%) and one deteriorated after surgery (11.1%). Conservatively treated patients had a higher deterioration rate on follow-up with 3/8 patients deteriorating (37.5%). In our pooled analysis, 109/145 (75.2%) of patients improved, 32/145 (22.1%) remained stable and 4/145 patients deteriorated (2.8%). Among the available data of nine cohorts, mean recovery rate measured by the JOA score was 36.6% (SD 14.4). In our pooled multivariable model lower preoperative JOA score was associated with worse functional outcome (OR 0.86, 95%CI 0.74–0.99, p ​= ​.04).

Discussion and conclusion

Our data shows that patients who are treated surgically have a higher improvement rate and acceptable perioperative morbidity compared to conservatively treated patients. Lower preoperative JOA score decreases chances of improved functional outcome on follow-up. We therefore advocate early surgery for symptomatic patients. Wait and see appears outdated due to progressive impairment and decreased chances of recovery. However, it is still an option in asymptomatic incidental SCH patients.

•

Evaluation of 17 patients with myelon herniation, 9 undergoing surgical treatment, 8 choosing conservative treatment.

•

In the surgically treated group, 44.4% improved after surgery compared to none in the conservative group.

•

11.1% deteriorated in the surgically treated compared to 37.5% in the conservatively treated group.

•

Surgically treated patients have a higher improvement rate.

•

Lower preoperative JOA score is associated with less improvement advocating early surgery in symptomatic patients.

Endoscopic Transnasal Odontoidectomy for Ventral Decompression of the Craniovertebral Junction: Surgical Technique and Clinical Outcome in a Case Series of 19 Patients

BACKGROUND

Abnormalities and pathologies of the craniovertebral junction as well as space-occupying lesions of the odontoid process can result in myelopathy symptoms. A staged procedure with posterior stabilization and anterior transnasal endoscopic decompression is recently considered a less invasive alternative to the transoral approach. We present a considerably large case series focused on the operative technique and the long-term neurological clinical outcome.

OBJECTIVE

To determine the safety and efficacy of odontoidectomy performed via an endoscopic transnasal approach.

METHODS

We retrospectively reviewed all patients treated in our neurosurgical department from January 2009 to January 2020. Demographics, pre- and postoperative clinical status, and operative technique and complications were extracted and analyzed.

RESULTS

In total, 22 transnasal operations were performed in 19 patients from January 2009 to January 2020. All but one patient underwent posterior C1-C2 instrumentation prior to the anterior transnasal computed tomography (CT)-navigated full-endoscopic decompression. The median duration of symptoms before surgery was 3 mo. Complications occurred in 1 patient who died from septic organ failure because of his initial diagnosis of osteomyelitis. Postoperative CT imaging showed sufficient decompression in 16 patients, and 3 patients underwent a transnasal endoscopic re-decompression (16%).

CONCLUSION

Transnasal endoscopic odontoidectomy presents a safe procedure with a satisfying clinical and radiological postoperative outcome.

Surgical treatment and neurological outcome of infiltrating intramedullary astrocytoma WHO II-IV: a multicenter retrospective case series

Introduction

Primary malignant spinal astrocytomas present rare oncological entities with limited median survival and rapid neurological deterioration. Evidence on surgical therapy, adjuvant treatment, and neurological outcome is sparse. We aim to describe the treatment algorithm and clinical features on patients with infiltrating intramedullary astrocytomas graded WHO II–IV.

Methods

The following is a multicentered retrospective study of patients treated for spinal malignant glioma WHO II–IV in five high-volume neurosurgical departments from 2008 to 2019. Pilocytic astrocytomas were excluded. We assessed data on surgical technique, perioperative neurological status, adjuvant oncological therapy, and clinical outcome.

Results

40 patients were included (diffuse astrocytoma WHO II n = 11, anaplastic astrocytoma WHO III n = 12, WHO IV n = 17). Only 40% were functionally independent before surgery, most patients presented with moderate disability (47.5%). Most patients underwent a biopsy (n = 18, 45%) or subtotal tumor resection (n = 15, 37.5%), and 49% of the patients deteriorated after surgery. Patients with WHO III and IV tumors were treated with combined radiochemotherapy. Median overall survival (OS) was 46.5 months in WHO II, 25.7 months in WHO III, and 7.4 months in WHO IV astrocytomas. Preoperative clinical status and WHO significantly influenced the OS, and the extent of resection did not.

Conclusion

Infiltrating intramedullary astrocytomas WHO II–IV present rare entities with dismal prognosis. Due to the high incidence of surgery-related neurological impairment, the aim of the surgical approach should be limited to obtaining the histological tissue via a biopsy or, tumor debulking in cases with rapidly progressive severe preoperative deficits.

Visual acuity and its postoperative outcome after transsphenoidal adenoma resection

Transsphenoidal surgery (TSS) represents the gold standard of pituitary adenoma resection, providing a safe and minimal invasive treatment for patients suffering from symptoms of mass effect. The aim of this study is to analyze the postoperative improvement of visual function after adenoma resection and to identify prognostic factors for the postoperative clinical recovery. We performed a retrospective analysis of all consecutive patients treated via a transsphenoidal approach for pituitary adenomas from April 2006 to December 2019 in a high-volume neurosurgical department. Our primary outcome was postoperative visual acuity and visual field impairment; the clinical findings were followed up to 3 months after surgery and correlated with clinical and radiographic findings. In total, 440 surgeries were performed in our department for tumors of the sella region in a time period of 13 years via transsphenoidal approach, and 191 patients included in the analysis. Mean age was 55 years, and 98% were macroadenomas. Mean preoperative visual acuity in patients with preoperative impairment (n = 133) improved significantly from 0.64/0.65 to 0.72/0.75 and 0.76/0.8 (right eye R/left eye L) postoperatively and at 3 months follow-up (p < 0.001). Visual acuity significantly depended on Knosp classification but not Hardy grading. The strongest predictor for visual function recovery was age. Transsphenoidal pituitary tumor resection remains a safe and effective treatment in patients with preoperative visual impairment. It significantly improves visual acuity and field defects after surgery, and recovery continues at the 3 months follow-up examination.

Sub-decapitation in suicidal chainsaw injury: report of a rare case and operative management

Chainsaw accidents are severe injuries, mostly work-related and concerning upper or lower extremities. Few suicidal chainsaw injuries are reported, all of them fatal. We report the case of a 23-year-old man who attempted suicide by sub-decapitation with a chainsaw, its successful (peri-) operative management, and clinical course along with a discussion of the contemporary management and body of evidence of such lesions. Chainsaw injuries are severe traumas. Stepwise surgery with maximal functional reconstruction is safe and optimal clinical outcome can be achieved.

Awake Craniotomy and Resection of a Left Frontal High-Grade Glioma: 2-Dimensional Operative Video

A 48-yr-old female patient presented in our outpatients' clinic after an episode of speech arrest and seizures a week earlier. On physical examination, there were no neurological deficits. Cranial magnetic resonance imaging (MRI) revealed a contrast-enhancing tumor of the superior and middle frontal gyrus. A 18F-fluoroethyl-tyrosine positron emission tomography (FET-PET) showed a high tracer uptake, and we suspected the lesion to be a high-grade glioma. The tumor was located next to the cortical motor and language areas. We performed a left frontal craniotomy while the patient was asleep, and then conducted cortical and subcortical stimulation under an awake condition. The patient was asked to move her right upper extremity and to name objects. Based on MRI navigation, we achieved a complete tumor resection. Postoperative imaging confirmed gross total resection, and final histopathology revealed an anaplastic astrocytoma isocitrate dehydrogenase (IDH) mut, 1p19q noncodeleted WHO°III. The patient was discharged home on the fifth postoperative day with a supplementary motor area syndrome and diminishing word-finding difficulties. We safely achieved gross total tumor resection in a highly eloquent localization through awake craniotomy with direct cortical and subcortical stimulation and electrophysiological monitoring. Awake craniotomy remains the gold standard for tumor resection in eloquent language areas in our clinics.  We obtained informed consent from the patient.

Presence of Propionibacterium acnes in patients with aseptic bone graft resorption after cranioplasty: preliminary evidence for low-grade infection

OBJECTIVE

Autologous bone graft reimplantation remains the standard treatment after decompressive hemicraniectomy. Unfortunately, some patients present with signs of bone resorption without any visible signs of infection; the reasons remain unknown. Contamination with Propionibacterium acnes has been discussed as a potential source of the osteolytic process. The aim of this study was to investigate the microbial spectrum detected in samples of grafts from patients with aseptic bone resorption and compare them to septic bone graft infections in order to identify P. acnes as the specific pathogen of aseptic bone resorption.

METHODS

The authors retrospectively reviewed all patients treated for aseptic bone resorption between 2012 and 2017 in their neurosurgical department. Septic infections were used as a control group to gain information on the present bacterial spectrum. Perioperative data such as demographics, number of surgeries, and complications were assessed and compared with the microbiological analyses conducted in order to detect differences and potential sources for aseptic bone resorption and possible differences in bacterial contamination in septic and aseptic bone infection.

RESULTS

In total, 38 patients underwent surgery between 2012 and 2017 for septic bone infection-14 for aseptic bone resorption. In 100% of the septic bone infection cases in which bone flap removal was needed, bacteria could be isolated from the removed bone flap (55% Staphylococcus aureus, 13.2% Enterococcus faecalis, and 18.4% Staphylococcus epidermidis). The microbial spectrum from samples of aseptic bone flaps with resorption was examined in 10 of 14 patients and revealed contamination with P. acnes in 40% (n = 4, the other 6 bone grafts were sterile), especially in sonication analysis, whereas visible septic bone infection was mainly caused by S. aureus without detection of P. acnes.

CONCLUSIONS

Aseptic bone resorption may be caused by low-grade infections with P. acnes. However, further analysis needs to be conducted in order to understand its clinical relevance and treatment perspective.

Comparison between electric-field-navigated and line-navigated TMS for cortical motor mapping in patients with brain tumors

BACKGROUND

For the navigation of transcranial magnetic stimulation (TMS), various techniques are available. Yet, there are two basic principles underlying them all: electric-field-navigated transcranial magnetic stimulation (En-TMS) and line-navigated transcranial magnetic stimulation (Ln-TMS). The current study was designed to compare both methods.

METHODS

To explore whether there is a difference in clinical applicability, workflow, and mapping results of both techniques, we systematically compared motor mapping via En-TMS and Ln-TMS in 12 patients suffering from brain tumors.

RESULTS

The number of motor-positive stimulation spots and the ratio of positive spots per overall stimulation numbers were significantly higher for En-TMS (motor-positive spots: En-TMS vs. Ln-TMS: 128.3 ± 35.0 vs. 41.3 ± 26.8, p < 0.0001; ratio of motor-positive spots per number of stimulations: En-TMS vs. Ln-TMS: 38.0 ± 9.2 % vs. 20.0 ± 14.4 %, p = 0.0031). Distances between the En-TMS and Ln-TMS motor hotspots were 8.3 ± 4.4 mm on the ipsilesional and 8.6 ± 4.5 mm on the contralesional hemisphere (p = 0.9124).

CONCLUSIONS

The present study compares En-TMS and Ln-TMS motor mapping in the neurosurgical context for the first time. Although both TMS systems tested in the present study are explicitly designed for application during motor mapping in patients with brain lesions, there are differences in applicability, workflow, and results between En-TMS and Ln-TMS, which should be distinctly considered during clinical use of the technique. However, to draw final conclusions about accuracy, confirmation of motor-positive Ln-TMS spots by intraoperative stimulation is crucial within the scope of upcoming investigations.

Resection of highly language-eloquent brain lesions based purely on rTMS language mapping without awake surgery

BACKGROUND

The resection of left-sided perisylvian brain lesions harbours the risk of postoperative language impairment. Therefore the individual patient's language distribution is investigated by intraoperative direct cortical stimulation (DCS) during awake surgery. Yet, not all patients qualify for awake surgery. Non-invasive language mapping by repetitive navigated transcranial magnetic stimulation (rTMS) has frequently shown a high correlation in comparison with the results of DCS language mapping in terms of language-negative brain regions. The present study analyses the extent of resection (EOR) and functional outcome of patients who underwent left-sided perisylvian resection of brain lesions based purely on rTMS language mapping.

METHODS

Four patients with left-sided perisylvian brain lesions (two gliomas WHO III, one glioblastoma, one cavernous angioma) underwent rTMS language mapping prior to surgery. Data from rTMS language mapping and rTMS-based diffusion tensor imaging fibre tracking (DTI-FT) were transferred to the intraoperative neuronavigation system. Preoperatively, 5 days after surgery (POD5), and 3 months after surgery (POM3) clinical follow-up examinations were performed.

RESULTS

No patient suffered from a new surgery-related aphasia at POM3. Three patients underwent complete resection immediately, while one patient required a second rTMS-based resection some days later to achieve the final, complete resection.

CONCLUSIONS

The present study shows for the first time the feasibility of successfully resecting language-eloquent brain lesions based purely on the results of negative language maps provided by rTMS language mapping and rTMS-based DTI-FT. In very select cases, this technique can provide a rescue strategy with an optimal functional outcome and EOR when awake surgery is not feasible.