Neurosurgical techniques involve precise manipulations in confined spaces. For surgical procedures in the brain, precision is particularly important due to the density of neurological structures. Further, the relative sensitivity of brain tissue, coupled with the potential severity of degraded tissue, make precise procedures that minimize collateral effects to surrounding tissue of utmost importance. In recent decades, usage of endoscopic surgical instruments have gained popularity over traditional procedures which removed a portion of the skull for open access.
Minimally invasive procedures using endoscopic techniques employ narrow, elongated instruments through smaller incisions, rather than open techniques. Surgical procedures with endoscopic techniques have been mostly performed for intraventricular procedures in the brain. There are many types of endoscopes which generally share some common features: light source, lens system, attached camera and working channels to introduce the surgical instruments. For example, a craniotomy is surgical procedure where a small opening is made in the skull to gain access to a tumor. The craniotomy is the fundamental technique used in tumor resection. It involves making an incision in the patient's scalp and then an opening in the skull. This is done using specialized endoscopic drills. Such an opening allows access to the intracranial cavity where the brain and ventricle are located.