Operative treatment of subcortical metastatic tumours in the central region

Treatment Options for Brain Metastases

OPINION STATEMENT

Therapies for brain metastasis continue to evolve as the life expectancies for patients have continued to prolong. Novel advances include the use of improved technology for radiation delivery, surgical guidance, and response assessment, along with systemic therapies that can pass through the blood brain barrier. With increasing complexity of treatments and the increased need for salvage treatments, multi-disciplinary management has become significantly more important.

Functional MRI applications for intra-axial brain tumours: uses and nuances in surgical practise

PURPOSE

Functional MRI (fMRI) has well-established uses to inform risks and plan maximally safe approaches in neurosurgery. In the field of brain tumour surgery, however, fMRI is currently in a state of clinical equipoise due to debate around both its sensitivity and specificity.

MATERIALS AND METHODS

In this review, we summarise the role and our experience of fMRI in neurosurgery for gliomas and metastases. We discuss nuances in the conduct and interpretation of fMRI that, based on our practise, most directly impact fMRI's usefulness in the neurosurgical setting.

RESULTS

Illustrated examples in which fMRI in our hands directly influences the neurosurgical treatment of brain tumours include evaluating the probability and nature of functional risks, especially for language functions. These presurgical risk assessments, in turn, help to predict the resectability of tumours, select or deselect patients for awake surgery, indicate the need for neurophysiological monitoring and guide the optimal use of intra-operative stimulation mapping. A further emerging application of fMRI is in measuring functional adaptation of functional networks after (partial) surgery, of potential use in the timing of further surgery.

CONCLUSIONS

In appropriately selected patients with a clearly defined surgical question, fMRI offers a valuable complementary tool in the pre-surgical evaluation of brain tumours. However, there is a great need for standards in the administration and analysis of fMRI as much as in the techniques that it is commonly evaluated against. Surprisingly little data exists that evaluates the accuracy of fMRI not just against complementary methods, but in terms of its ultimate clinical aim of minimising post-surgical morbidity.

Awake craniotomy removal of a corticospinal tract developmental venous anomaly hemorrhage: A case report

Developmental venous anomalies (DVAs) are composed of mature venous vessels that lack malformed or neoplastic elements. Although the hemorrhage risk is considered negligible, some patients may have neurological symptoms attributable to acute infarction or intracranial hemorrhage secondary to thrombosis, in the absence of a coexisting cavernous malformation. We report the case of a 42-year-old patient who presented with acute left-hand paresis secondary to a subcortical hemorrhage. This bleeding originated from a DVA in the corticospinal tract area and was surgically drained through an awake craniotomy. To accomplish this, we used a trans-precentral sulcus approach. After the complete removal of the coagulum, small venous channels appeared, which were coagulated. No associated cavernoma was found. Although the main DVA trunk was left patent, no signs of ischemia or venous infarction were observed after coagulating the small venous channels found inside the hematoma cavity. Two weeks after the procedure, the patient's hand function improved, and he was able to resume desktop work. DVA-associated hemorrhage within the cortico-spinal tract could be safely removed with modern awake mapping techniques. This technique allowed the patient to rapidly improve his hand function.

Maximal Safe Resection in Glioblastoma Surgery: A Systematic Review of Advanced Intraoperative Image-Guided Techniques

Glioblastoma multiforme (GBM) represents the most common and aggressive central nervous system tumor associated with a poor prognosis. The aim of this study was to depict the role of intraoperative imaging techniques in GBM surgery and how they can ensure the maximal extent of resection (EOR) while preserving the functional outcome. The authors conducted a systematic review following PRISMA guidelines on the PubMed/Medline and Scopus databases. A total of 1747 articles were identified for screening. Studies focusing on GBM-affected patients, and evaluations of EOR and functional outcomes with the aid of advanced image-guided techniques were included. The resulting studies were assessed for methodological quality using the Risk of Bias in Systematic Review tool. Open Science Framework registration DOI 10.17605/OSF.IO/3FDP9. Eighteen studies were eligible for this systematic review. Among the selected studies, eight analyzed Sodium Fluorescein, three analyzed 5-aminolevulinic acid, two evaluated IoMRI imaging, two evaluated IoUS, and three evaluated multiple intraoperative imaging techniques. A total of 1312 patients were assessed. Gross Total Resection was achieved in the 78.6% of the cases. Follow-up time ranged from 1 to 52 months. All studies assessed the functional outcome based on the Karnofsky Performance Status scale, while one used the Neurologic Assessment in Neuro-Oncology score. In 77.7% of the cases, the functional outcome improved or was stable over the pre-operative assessment. Combining multiple intraoperative imaging techniques could provide better results in GBM surgery than a single technique. However, despite good surgical outcomes, patients often present a neurocognitive decline leading to a marked deterioration of the quality of life. Advanced intraoperative image-guided techniques can allow a better understanding of the anatomo-functional relationships between the tumor and the surrounding brain, thus maximizing the EOR while preserving functional outcomes.

Linac-based stereotactic radiosurgery and fractionated stereotactic radiotherapy with a micro-multileaf collimator for brain metastasis in the primary motor cortex

This study aimed to assess the clinical outcomes of linear accelerators (linac)-based, stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) with a micro-multileaf collimator for brain metastasis in the primary motor cortex (BMPMC). Thirty-five consecutive patients with BMPMC who were treated by linac-based SRS or fSRT between January 2012 and March 2020 were analyzed. BMPMC was defined as a tumor located in the precentral gyrus on gadolinium-enhanced magnetic resonance imaging (MRI) and T2-weghted imaging (T2WI). In total, 35 patients with 37 metastases were analyzed. The median follow-up time was 13 (range: 1-97) months. The tumor volume was 0.05-26.5 (median: 0.62) cm3. All patients were treated with SRS or fSRT using 35 Gy with 7 Gy per fraction daily. The median survival time (MST) was 16.9 months. The pretreatment KPS and RPA class significantly differed in terms of MST on the log-rank tests. Seven symptomatic patients had hemiparesis before SRS or fSRT. All symptomatic patients, except one with facial paresis and one who died within 3 months, experienced improvement at a 3 month follow-up. None of the patients presented with persistent radiation injury at the final follow-up. Two patients presented with grade 3 radiation-related central nervous system necrosis, which was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. In BMPMC, SRS and fSRT had good tumor control and did not cause serious complications. Therefore, they are suitable treatment options with an acceptable safety profile.

Motor Evoked Potential Warning Criteria in Supratentorial Surgery: A Scoping Review

During intraoperative monitoring of motor evoked potentials (MEP), heterogeneity across studies in terms of study populations, intraoperative settings, applied warning criteria, and outcome reporting exists. A scoping review of MEP warning criteria in supratentorial surgery was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Sixty-eight studies fulfilled the eligibility criteria. The most commonly used alarm criteria were MEP signal loss, which was always a major warning sign, followed by amplitude reduction and threshold elevation. Irreversible MEP alterations were associated with a higher number of transient and persisting motor deficits compared with the reversible changes. In almost all studies, specificity and Negative Predictive Value (NPV) were high, while in most of them, sensitivity and Positive Predictive Value (PPV) were rather low or modest. Thus, the absence of an irreversible alteration may reassure the neurosurgeon that the patient will not suffer a motor deficit in the short-term and long-term follow-up. Further, MEPs perform well as surrogate markers, and reversible MEP deteriorations after successful intervention indicate motor function preservation postoperatively. However, in future studies, a consensus regarding the definitions of MEP alteration, critical duration of alterations, and outcome reporting should be determined.

Can Preoperative Mapping with Functional MRI Reduce Morbidity in Brain Tumor Resection? A Systematic Review and Meta-Analysis of 68 Observational Studies

Background Preoperative functional MRI (fMRI) is one of several techniques developed to localize critical brain structures and brain tumors. However, the usefulness of fMRI for preoperative surgical planning and its potential effect on neurologic outcomes remain unclear. Purpose To assess the overall postoperative morbidity among patients with brain tumors by using preoperative fMRI versus surgery without this tool or with use of standard (nonfunctional) neuronavigation. Materials and Methods A systematic review and meta-analysis of studies across major databases from 1946 to June 20, 2020, were conducted. Inclusion criteria were original studies that (a) included patients with brain tumors, (b) performed preoperative neuroimaging workup with fMRI, (c) investigated the usefulness of a preoperative or intraoperative functional neuroimaging technique and used that technique to resect cerebral tumors, and (d) reported postoperative clinical measures. Pooled estimates for adverse event rate (ER) effect size (log ER, log odds ratio, or Hedges g) with 95% CIs were computed by using a random-effects model. Results Sixty-eight studies met eligibility criteria (3280 participants; 58.9% men [1555 of 2641]; mean age, 46 years ± 8 [standard deviation]). Functional deterioration after surgical procedure was less likely to occur when fMRI mapping was performed before the operation (odds ratio, 0.25; 95% CI: 0.12, 0.53; P < .001]), and postsurgical Karnofsky performance status scores were higher in patients who underwent fMRI mapping (Hedges g, 0.66; 95% CI: 0.21, 1.11; P = .004]). Craniotomies for tumor resection performed with preoperative fMRI were associated with a pooled adverse ER of 11% (95% CI: 8.4, 13.1), compared with a 21.0% ER (95% CI: 12.2, 33.5) in patients who did not undergo fMRI mapping. Conclusion From the currently available data, the benefit of preoperative functional MRI planning for the resection of brain tumors appears to reduce postsurgical morbidity, especially when used with other advanced imaging techniques, such as diffusion-tensor imaging, intraoperative MRI, or cortical stimulation. © RSNA, 2021 Online supplemental material is available for this article.

Surgical Management of Brain Metastases in the Perirolandic Region

Brain metastases (BM) are the most frequent intracranial tumors, which may result in significant morbidity and mortality when the lesions involve the perirolandic region. Surgical intervention for BM in the perirolandic region is still under discussion even though prompt relief of mass effect and avoidance of necrosis together with brain edema may not be achieved by radiotherapy. More recently, several researchers attempt to evaluate the benefit of surgery for BM within this pivotal sensorimotor area. Nevertheless, data are sparse and optimal treatment paradigm is not yet widely described. Since the advance in intraoperative neuroimaging and neurophysiology, resection of BM in the perirolandic region has been proven to be safe and efficacious, sparing this eloquent area while retaining reasonably low morbidity rates. Although management of BM becomes much more tailored and multimodal, surgery remains the cornerstone and principles of resection as well as indications for surgery should be well defined. This is the first review concerning the characteristics of BM involving the perirolandic region and the current impact of surgical therapy for the lesions. Future perspectives of advanced neurosurgical techniques are also presented.

Current Applications of Diffusion Tensor Imaging and Tractography in Intracranial Tumor Resection

In the treatment of brain tumors, surgical intervention remains a common and effective therapeutic option. Recent advances in neuroimaging have provided neurosurgeons with new tools to overcome the challenge of differentiating healthy tissue from tumor-infiltrated tissue, with the aim of increasing the likelihood of maximizing the extent of resection volume while minimizing injury to functionally important regions. Novel applications of diffusion tensor imaging (DTI), and DTI-derived tractography (DDT) have demonstrated that preoperative, non-invasive mapping of eloquent cortical regions and functionally relevant white matter tracts (WMT) is critical during surgical planning to reduce postoperative deficits, which can decrease quality of life and overall survival. In this review, we summarize the latest developments of applying DTI and tractography in the context of resective surgery and highlight its utility within each stage of the neurosurgical workflow: preoperative planning and intraoperative management to improve postoperative outcomes.

A purely functional Imaging based approach for transcortical resection of lesion involving the dominant atrium: Towards safer, imaging-guided, tailored cortico-leucotomies

BACKGROUND AND STUDY OBJECT

The Dominant Atrium (DA) is a crossroad of eloquent white matter bundles difficult to preserve with a standard "anatomical" approach. The aim of this work is to evaluate the results of a cohort of patients who underwent surgery with the aid of a purely functional MRI and DTI-based approach.

MATERIALS AND METHODS

43 patients suffering from lesions involving the DA have been included in the final cohort and studied in regards to quality of life (KPS); a special attention was lent on the incidence of new or worsening of preexisting neurological deficits, with a focus on motor, visual and speech disturbances after the surgical treatment. Patient, surgery and lesion-related data were recorded to identify the relationships with outcome. Eloquent areas fMRI and the course of Arcuate Fasciculus (AF), Inferior frontooccipital fasciculus (IFOF), Optic radiation (OR) and corticospinal tract (CST) have been investigated with preoperative MRI sequences and DTI reconstruction.

RESULTS

The final cohort consisted of 43 patients, 19 males and 24 females; average age was 56.8 years. We recorded 9 transient and 3 permanent postoperative deficits, only one of those was caused by an edema interference with DTI reconstruction. Preoperative functional status, histology and volume of the lesion proved to be independent factors affecting results.

CONCLUSIONS

A purely functional surgical approach to the DA provided promising preliminary results. A direct DTI-fMRI visualization of the eloquent structures proximal to DA allows surgeon to conceive an ultra-precise and "tailored" cortico-leucotomy for an optimal exposure of the lesion.

Recent technological advances in pediatric brain tumor surgery

X-rays and ventriculograms were the first imaging modalities used to localize intracranial lesions including brain tumors as far back as the 1880s. Subsequent advances in preoperative radiological localization included computed tomography (CT; 1971) and MRI (1977). Since then, other imaging modalities have been developed for clinical application although none as pivotal as CT and MRI. Intraoperative technological advances include the microscope, which has allowed precise surgery under magnification and improved lighting, and the endoscope, which has improved the treatment of hydrocephalus and allowed biopsy and complete resection of intraventricular, pituitary and pineal region tumors through a minimally invasive approach. Neuronavigation, intraoperative MRI, CT and ultrasound have increased the ability of the neurosurgeon to perform safe and maximal tumor resection. This may be facilitated by the use of fluorescing agents, which help define the tumor margin, and intraoperative neurophysiological monitoring, which helps identify and protect eloquent brain.

Magnetic Resonance-Guided Laser-Induced Thermal Therapy for Recurrent Brain Metastases in the Motor Strip After Stereotactic Radiosurgery

The authors report a challenging case of a brain metastasis located in the motor cortex, which was not responsive to radiosurgery. Use of a novel technique, magnetic resonance-guided laser-induced thermotherapy (MRgLITT), resulted in the complete obliteration of the lesion without adverse effects or evidence of tumor recurrence at follow-up. This case illustrates that MRgLITT may provide a viable alternative for patients with brain metastases refractory to radiosurgery or in deep locations, where both stereotactic radiosurgery (SRS) and surgical resection may be ineffective.  

Functional approach using intraoperative brain mapping and neurophysiological monitoring for the surgical treatment of brain metastases in the central region

OBJECTIVE Brain metastases are the most frequent intracranial malignant tumor in adults. Surgical intervention for metastases in eloquent areas remains controversial and challenging. Even when metastases are not infiltrating intra-parenchymal tumors, eloquent areas can be affected. Therefore, this study aimed to describe the role of a functional guided approach for the resection of brain metastases in the central region. METHODS Thirty-three patients (19 men and 14 women) with perirolandic metastases who were treated at the authors' institution were reviewed. All participants underwent resection using a functional guided approach, which consisted of using intraoperative brain mapping and/or neurophysiological monitoring to aid in the resection, depending on the functionality of the brain parenchyma surrounding each metastasis. Motor and sensory functions were monitored in all patients, and supplementary motor and language area functions were assessed in 5 and 4 patients, respectively. Clinical data were analyzed at presentation, discharge, and the 6-month follow-up. RESULTS The most frequent presenting symptom was seizure, followed by paresis. Gross-total removal of the metastasis was achieved in 31 patients (93.9%). There were 6 deaths during the follow-up period. After the removal of the metastasis, 6 patients (18.2%) presented with transient neurological worsening, of whom 4 had worsening of motor function impairment and 2 had acquired new sensory disturbances. Total recovery was achieved before the 3rd month of follow-up in all cases. Excluding those patients who died due to the progression of systemic illness, 88.9% of patients had a Karnofsky Performance Scale score greater than 80% at the 6-month follow-up. The mean survival time was 24.4 months after surgery. CONCLUSIONS The implementation of intraoperative electrical brain stimulation techniques in the resection of central region metastases may improve surgical planning and resection and may spare eloquent areas. This approach also facilitates maximal resection in these and other critical functional areas, thereby helping to avoid new postoperative neurological deficits. Avoiding permanent neurological deficits is critical for a good quality of life, especially in patients with a life expectancy of over a year.

Surgery on motor area metastasis

The role of surgery on central area metastasis remains unclear, and outcome data are still controversial. The aim of our study is to analyze the predictive value of clinical and surgical data on motor and functional outcome of patients, taking into account new emerging data on boundary irregularity of brain metastasis. We retrospectively analyzed 47 consecutive patients who underwent surgery assisted by neurophysiologic monitoring for a solitary metastasis in central area between 2010 and 2013. Inclusion criteria were as follows: good functional status (Karnofsky Performance Status (KPS) ≥70), controlled systemic disease, and absence of extra-cranial dissemination. At 1-month follow up, motor and functional outcomes were compared with preoperative clinical status, response to corticosteroids, extent of tumor resection, boundary irregularity, and size of tumor. Gross total resection was achieved in 93.6% of cases. In preoperative symptomatic patients, motor outcome (according to Medical Research Council grading scale) improved in 55.5% and worsened in 16.7%, while functional outcome (according to KPS score) improved in 50% and worsened in 14.2% of cases. No worsening occurred in preoperative asymptomatic patients. Motor outcome resulted to be not correlated with preoperative deficits, tumor volume, or preoperative response to corticosteroid treatment. Remarkably, motor outcome and extent of surgical resection appeared strongly correlated with tumor boundary irregularity (p < 0.05). Surgery with neurophysiologic monitoring on motor area metastasis can improve functional and motor condition in selected patients. Tumor volume does not represent a limit in surgery. The high correlation between clinical outcome, resection rate, and tumor boundary irregularity strengthens a new belief on the infiltrative growing pattern of brain metastasis. Motor function was evaluated according to Medical Research Council grading scale (Ott et al. 2014) while functional status was assessed according to KPS score.

Resection of supratentorial gliomas: the need to merge microsurgical technical cornerstones with modern functional mapping concepts. An overview

Although surgery is not curative for the majority of intracranial gliomas, radical resection has been demonstrated to influence survival and delay tumor progression. Because gliomas are very frequently located in eloquent or more generally critical areas, surgeons must always balance the maximizing resection with the need to preserve neurological function. In this overview, we tried to summarize the recent literature and our personal experience about (1) the benefits and limits of using preoperative anatomical and functional neuroimaging (anatomical MRI, DTI fiber tracking, and functional MRI), (2) the issues to consider in planning the surgical strategy, (3) the need to thoroughly understand microsurgical techniques that enable a maximal resection (subpial dissection, vascular manipulation, etc.), (4) the importance of individualizing surgical strategy especially in patients with gliomas in eloquent areas (the role of neuropsychological evaluation in redefining eloquent and non-eloquent areas), and (5) how to use intraoperative mapping techniques and understand why and when to use them. Through this paper, the reader should become more familiar with a comprehensive panel of techniques and methodologies but more importantly become aware that these recent technical advances facilitate a conceptual change from classical surgical paradigms toward a more patient-specific approach.

The role of magnetic resonance imaging in the management of brain metastases: diagnosis to prognosis

This article reviews the different MRI techniques available for the diagnosis, treatment and monitoring of brain metastases with a focus on applying advanced MR techniques to practical clinical problems. Topics include conventional MRI sequences and contrast agents, functional MR imaging, diffusion weighted MR, MR spectroscopy and perfusion MR. The role of radiographic biomarkers is discussed as well as future directions such as molecular imaging and MR guided high frequency ultrasound.

Current approaches to the treatment of metastatic brain tumours

Metastatic tumours involving the brain overshadow primary brain neoplasms in frequency and are an important complication in the overall management of many cancers. Importantly, advances are being made in understanding the molecular biology underlying the initial development and eventual proliferation of brain metastases. Surgery and radiation remain the cornerstones of the therapy for symptomatic lesions; however, image-based guidance is improving surgical technique to maximize the preservation of normal tissue, while more sophisticated approaches to radiation therapy are being used to minimize the long-standing concerns over the toxicity of whole-brain radiation protocols used in the past. Furthermore, the burgeoning knowledge of tumour biology has facilitated the entry of systemically administered therapies into the clinic. Responses to these targeted interventions have ranged from substantial toxicity with no control of disease to periods of useful tumour control with no decrement in performance status of the treated individual. This experience enables recognition of the limits of targeted therapy, but has also informed methods to optimize this approach. This Review focuses on the clinically relevant molecular biology of brain metastases, and summarizes the current applications of these data to imaging, surgery, radiation therapy, cytotoxic chemotherapy and targeted therapy.

Risks of postoperative paresis in motor eloquently and non-eloquently located brain metastases

Background

When treating cerebral metastases all involved multidisciplinary oncological specialists have to cooperate closely to provide the best care for these patients. For the resection of brain metastasis several studies reported a considerable risk of new postoperative paresis. Pre- and perioperative chemotherapy (Ctx) or radiotherapy (Rtx) alter vasculature and adjacent fiber tracts on the one hand, and many patients already present with paresis prior to surgery on the other hand. As such factors were repeatedly considered risk factors for perioperative complications, we designed this study to also identify risk factors for brain metastases resection.

Methods

Between 2006 and 2011, we resected 206 brain metastases consecutively, 56 in eloquent motor areas and 150 in non-eloquent ones. We evaluated the influences of preoperative paresis, previous Rtx or Ctx as well as recursive partitioning analysis (RPA) class on postoperative outcome.

Results

In general, 8.7% of all patients postoperatively developed a new permanent paresis. In contrast to preoperative Ctx, previous Rtx as a single or combined treatment strategy was a significant risk factor for postoperative motor weakness. This risk was even increased in perirolandic and rolandic lesions. Our data show significantly increased risk of new deficits for patients assigned to RPA class 3. Even in non-eloquently located brain metastases the risk of new postoperative paresis has not to be underestimated. Despite the microsurgical approach, our cohort shows a high rate of unexpected residual tumors in postoperative MRI, which supports recent data on brain metastases’ infiltrative nature but might also be the result of our strict study protocol.

Conclusions

Surgical resection is a safe treatment of brain metastases. However, preoperative Rtx and RPA score 3 have to be taken into account when surgical resection is considered.

Postoperative ischemic changes following brain metastasis resection as measured by diffusion-weighted magnetic resonance imaging

Object

Brain metastases occur in 10% to 40% of patients harboring cancer. In cases of neurosurgical metastasis resection, all postoperative neurological deterioration should be avoided. Reasons for postoperative deficits can be direct tissue damage due to resection, hemorrhage, venous congestive infarcts, or arterial ischemic events leading to tissue infarction. The aim of this study was to evaluate whether postoperative ischemic infarctions occur in surgery for brain metastasis and to determine their influence on new postoperative neurological deficits.

Methods

Patients who underwent resection of brain metastases and had preoperative and early postoperative (within 48 hours) MRI scans, including diffusion-weighted imaging sequences and apparent diffusion coefficient maps, between January 2009 and May 2012 were included in this study. Clinical and histopathological data (histopathological results, pre- and postoperative neurological status, and previous tumor-specific therapy) were recorded.

Results

One hundred twenty-two patients (56 male, 66 female) who underwent resection of brain metastases were included. The patients' mean age was 60 years (range 21–89 years). The mean time span from initial tumor diagnosis to resection of brain metastasis was 44 months (range 0–338 months). The mean preoperative Karnofsky Performance Status was 80% (exact mean 76% ± 17% [SD]), and the mean postoperative value was 80% (exact mean 78% ± 17%). Twelve (9.8%) of the 122 patients had postoperative permanent worsening of a neurological deficit or a new permanent neurological deficit; 44 (36.1%) of the 122 patients had postoperative ischemic lesions. When comparing patients with and without previous brain irradiation, 53.8% of patients with previous brain irradiation had ischemic lesions on postoperative imaging compared with 31.3% of patients without previous brain irradiation (p = 0.033). There was a significant association between ischemia and postoperative neurological status deterioration (transient or permanent); 13 (29.5%) of 44 patients with ischemic lesions had deterioration of their neurological status compared with 7 (9%) of the 78 patients who did not have ischemic lesions (p = 0.003).

Conclusions

This study demonstrates a high prevalence of vascular incidents in patients undergoing resection for metastatic brain disease. Patients harboring postoperative ischemic lesions detected by MRI have a higher rate of neurological deficits (transient or permanent). Patients who had previous irradiation therapy are at higher risk of developing postoperative ischemic lesions. A large number of postoperative neurological deficits are caused by ischemic incidents.

Neuronavigation in the surgical management of brain tumors: current and future trends

Neuronavigation has become an ubiquitous tool in the surgical management of brain tumors. This review describes the use and limitations of current neuronavigational systems for brain tumor biopsy and resection. Methods for integrating intraoperative imaging into neuronavigational datasets developed to address the diminishing accuracy of positional information that occurs over the course of brain tumor resection are discussed. In addition, the process of integration of functional MRI and tractography into navigational models is reviewed. Finally, emerging concepts and future challenges relating to the development and implementation of experimental imaging technologies in the navigational environment are explored.

Selective excision of cerebral metastases from the precentral gyrus

BACKGROUND

The surgical management of cerebral metastases to the eloquent cortex is a controversial topic. Precentral gyrus lesions are often treated with whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS) because of the concern for causing new or worsened postoperative neurological deficits. However, there is evidence in the literature that radiation therapy carries significant risk of complication. We present a series of patients who were symptomatic from a precentral gyrus metastasis and underwent surgical excision.

METHODS

During a 2-year period from 2010 to 2012, 17 consecutive patients harboring a cerebral metastasis within the precentral gyrus underwent microsurgical resection. All patients were discussed at a multi-disciplinary tumor board. The prerequisite for neurosurgical treatment was stable systemic disease and life expectancy greater than 6 months as determined by the patient's oncologist. Patients also were required to harbor a symptomatic lesion within the motor cortex, defined as the precentral gyrus.

RESULTS

We present the 3-month neurological outcome for this group of patients. Surgery was uneventful and without any severe perioperative complications in all 17 patients. At 3 month follow up, symptoms had improved or been stabilized in 94.1% of patients and were worsened in 5.9%.

CONCLUSION

Our results have shown that surgery for cerebral metastases in the precentral gyrus can be done safely and improve or stabilize the neurological function of most patients. Microsurgical resection of precentral gyrus metastases should be a treatment option for patients with single or multiple lesions who present a focal neurologic deficit. This can be performed safely and without intraoperative cortical mapping.

FACT-Br for assessment of quality of life in patients receiving treatment for brain metastases: a literature review

INTRODUCTION

Brain metastases are a significant cause of morbidity and mortality for patients with advanced cancers, and quality-of-life (QoL) end points are most appropriate for this population. The Functional Assessment of Cancer Therapy (FACT) questionnaires are commonly used to assess cancer-related QoL issues. The FACT-Brain (FACT-Br) provides an additional set of disease-specific questions pertaining to brain neoplasms. We aim to provide a comprehensive review to examine the use of the FACT-Br as a QoL assessment for patients with brain metastases.

MATERIALS & METHODS

A review of the literature was conducted and all studies utilizing the FACT-Br for QoL assessment of patients with brain metastases were included. Study information and relevant information regarding the FACT-Br were extracted.

RESULTS

A total of 14 studies were identified representing various treatment options (radiation, chemotherapy and surgery) for patients with brain metastases. All studies utilized at least part of the FACT-Br as the main QoL assessment. In addition, neurocognitive and performance status assessments were performed in nine and 12 out of 14 studies, respectively. Issues of poor accrual, compliance and attrition were common and posed problems in reaching statistically significant changes in QoL despite changes in raw QoL scores.

CONCLUSION

Studies involving patients with brain metastases should continue to utilize QoL tools such as the FACT-Br; however, this tool still requires validation for use in this patient population. Additional studies should observe the relationship between neurocognitive function and QoL, and attempt to minimize poor accrual and compliance issues through modifications of trial design and reduction of patient burden.