Glioblastoma (GBM) is the most common primary intracranial neoplasia, and is characterized by its extremely poor prognosis. Despite maximum surgery, chemotherapy, and radiation, the histological heterogeneity of GBM makes total eradication impossible, due to residual cancer cells invading the parenchyma, which is not otherwise seen in radiographic images. Even with gross total resection, the heterogeneity and the dormant nature of brain tumor initiating cells allow for therapeutic evasion, contributing to its recurrence and malignant progression, and severely impacting survival. Visual delimitation of the tumor’s margins with common surgical techniques is a challenge faced by many surgeons. In an attempt to achieve optimal safe resection, advances in approaches allowing intraoperative analysis of cancer and non-cancer tissue have been developed and applied in humans resulting in improved outcomes. In addition, functional paradigms based on stimulation techniques to map the brain’s electrical activity have optimized glioma resection in eloquent areas such as the Broca’s, Wernike’s and perirolandic areas. In this review, we will elaborate on the current standard therapy for newly diagnosed and recurrent glioblastoma with a focus on surgical approaches. We will describe current technologies used for glioma resection, such as awake craniotomy, fluorescence guided surgery, laser interstitial thermal therapy and intraoperative mass spectrometry. Additionally, we will describe a newly developed tool that has shown promising results in preclinical experiments for brain cancer: optical coherence tomography.

Spinal instrumentation has made significant advances in the last two decades, with transpedicular constructs now widely used in spinal fixation. Pedicle screw constructs are routinely used in thoracolumbar-instrumented fusions, and in recent years, the cervical spine as well. Three-column fixations with pedicle screws provide the most rigid form of posterior stabilization. Surgical landmarks and fluoroscopy have been used routinely for pedicle screw insertion, but a number of studies reveal inaccuracies in placement using these conventional techniques (ranging from 10% to 50%). The ability to combine 3D imaging with intraoperative navigation systems has improved the accuracy and safety of pedicle screw placement, especially in more complex spinal deformities. However, in the authors' experience with image guidance in more than 1500 cases, several potential pitfalls have been identified while using intraoperative spinal navigation that could lead to suboptimal results. This article summarizes the authors' experience with these various pitfalls using spinal navigation, and gives practical tips on their avoidance and management.

Whole-brain radiotherapy and stereotactic radiosurgery (SRS) play a central role in the treatment of metastatic brain tumors. Radiation necrosis occurs in 5% of patients and can be very difficult to treat. The available treatment options for radiation necrosis include prolonged high-dose corticosteroids, hyperbaric oxygen, anticoagulation, bevacizumab, and surgical resection. We present the first report and results using laser-interstitial thermal therapy (LITT) for medically refractory radionecrosis. A 74-year-old diabetic patient who had a history of non-small cell lung cancer with brain metastases and subsequent treatment with SRS, presented with a focal lesion in the left centrum semiovale with progressively worsening edema. Image findings were consistent with radiation necrosis that was refractory despite prolonged, high-dose steroid therapy. His associated comorbidities obviated alternative interventions and the lesion was not in a location amenable to surgical resection. We used laser thermal ablation to treat the biopsy-proven radionecrosis. The procedure was tolerated well and the patient was discharged 48 hours postoperatively. Imaging at 7-week follow-up showed near complete resolution of the edema and associated mass effect. Additionally, the patient was completely weaned off steroids. To our knowledge this is the first report using LITT for the treatment of focal radiation necrosis. LITT may be an effective treatment modality for patients with medically refractory radiation necrosis with lesions not amenable to surgical decompression.

Magnetic resonance imaging-guided laser interstitial thermal therapy (LITT) is a minimally invasive treatment modality with recent increasing use to ablate brain tumors. When originally introduced in the late 1980s, the inability to precisely monitor and control the thermal ablation limited the adoption of LITT in neuro-oncology. Popularized as a means of destroying malignant hepatic and renal metastatic lesions percutaneously, its selective thermal tumor destruction and preservation of adjacent normal tissues have since been optimized for use in neuro-oncology. The progress made in real-time thermal imaging with MRI, laser probe design, and computer algorithms predictive of tissue kill has led to the resurgence of interest in LITT as a means to ablate brain tumors. Current LITT systems offer a surgical option for some inoperable brain tumors. We discuss the origins, principles, current indications, and future directions of MRI-guided LITT in neuro-oncology.