**1. Introduction**

Glioma is the most frequent malignant tumor of the brain, with a high mortality as the grade of glioma gets higher [1]. World Health Organization in 2016 classified glioma into four grades, where I and II grades are classified as low grade glioma and III and IV grades as high grade glioma [2]. Glioma surgery is one of the most common and challenging

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

surgeries for every neurosurgeon. The history of glioma surgery changed during the past century following all technical progresses. One of the biggest technical improvements started with the discovery of nuclear magnetic resonance in the 1950s, now known as magnetic resonance imaging [3]. After MRI introduction, the concept of maximal MRI visible tumor resection started to be the standard approach to glioma surgery. Nevertheless, this concept had a significant rate of morbidity, and it stranded to be valid for decades. During the past 25 years, the concept of surgical removal of gliomas has changed from a maximally aggressive for high grade glioma to minimally invasive but maximally efficient resection. The concept for low grade glioma changed also from "watch and wait" to active surgical treatment [4].

Grade I and II gliomas are classified as low grade glioma (LGG) and grade III and IV as high grade glioma (HGG). Surgical treatment options are different for every group of gliomas,

Neurosurgical Options for Glioma

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http://dx.doi.org/10.5772/intechopen.82603

In this review, we will present contemporary surgical techniques used in treatment of both glioma groups: LGG and HGG and the impact on patient's life. Surgery remains the core treatment for management of gliomas. Surgical resection of pathological tumor mass, almost nonfunctional brain region, is common, standard, and the oldest neurosurgical approach to contemporary neuro-oncology. Historically, glioma surgery was a controversial topic, but many recent studies have demonstrated the crucial place of glioma resection in the management of low and high grade gliomas [5]. Concerning glioma surgery, there are two big questions: what the actual impact of resection is on progression of glioma and what the functional risk of it is [6]. To improve the outcomes of these two questions in past decades, a huge improvement has been made in intraoperative techniques (neuronavigation, intraoperative MRI, intraoperative ultrasound, stimulation mapping techniques, and fluorescence-guided surgery; **Figure 1**) [7, 8]. These techniques were developed to maximize the resection of glioma and preserve or improve the quality of life [6, 7]. Before glioma surgery, the neurosurgeon must calculate all benefits and possible hazards which could influence on morbidity, mortality, and quality of

**Figure 1.** Typical intraoperative arrangement of the patient who undergoes tumor resection and the neurosurgeon, in the early stage of glioma surgery, immediately before dural opening. Microscope is positioned close to the surgeon's left arm and neuronavigation tool is in front (picture on the left). After the opening of the dura, characteristic findings of differently colored glioma affecting the brain cortex are presented. Tumor tissue bulks over the dural edge; it is

obviously white-grayish and much lighter, with strange pathological vascularization (picture on the right).

LGG and HGG, due the glioma life cycle [2].

There are few surgical options based on glioma type:

**2.1. Surgical techniques**

the rest of life.

• glioma biopsy.

• subtotal resection.

• gross total resection. • supratotal resection.

In the course of years, *subtotal resection* (STR) and *gross total resection* (GTR) evolved to *supratotal resection,* which became the surgical option especially for low grade glioma in the eloquent area and younger patients. With supratotal resection, neurosurgeons are trying to utilize minimally invasive surgery for the preservation of life quality as much as possible, but resecting most of tumor tissue using brain monitoring techniques, intraoperative imaging, awake surgery options, etc. The overall survival period with this approach was extended. As the new surgical concept, supratotal resection, which is actually also aggressive but selective, controlled, and monitored approach, over the years confirmed the highest level of general development of glioma surgery. In this respect, supratotal resection is probably becoming the most important part of *state of the art* in glioma management generally, but we are waiting for the results of big clinical trials. When the tumor infiltrates eloquent brain areas the challenge is how much to resect in balance of maximal safe resection and possible neurological deficit or worsening of functional status [4].

In this review, we are going to discuss surgical options for glioma treatment and the impact of it on the patient's life.
