Stereotactic guided insertion of DBS electrodes in neurosurgery
Neurosurgery (or neurological surgery) is the medical specialty concerned with the prevention, diagnosis, treatment, and rehabilitation of disorders which affect any portion of the nervous system including the brain, spinal cord, peripheral nerves, and extra-cranial cerebrovascular system.
Education and training
In different countries, there are different requirements for an individual to legally practice neurosurgery, and there are varying methods through which they must be educated. In most countries neurosurgeon training is a minimum period of 7 years after graduating from medical school.
In the United States, a neurosurgeon must generally complete four years of college, four years of medical school, and seven years of residency (PGY-1-7). Most, but not all, residency programs have some component of basic science or clinical research. Neurosurgeons may pursue an additional training in a fellowship, after residency or in some cases, as a senior resident. These fellowships include pediatric neurosurgery, trauma/neurocritical care, functional and stereotactic surgery, surgical neuro-oncology, radiosurgery, neurovascular surgery, Skull-Base Surgery, peripheral nerve and spine surgery. In the U.S., neurosurgery is considered a highly competitive specialty composed of 0.6% of all practicing physicians.
In the United Kingdom, students must gain entry into medical school. MBBS qualification (Bachelor of Medicine, Bachelor of Surgery) takes 4–6 years depending on the student's route. The newly qualified physician must then complete foundation training lasting two years; this is a paid training program in a hospital or clinical setting covering a range of medical specialties including surgery. Junior doctors then apply to enter the neurosurgical pathway. Unlike most other surgical specialties, it currently has its own independent training pathway which takes around eight years (ST1-8); before being able to sit for consultant exams with sufficient amounts of experience and practice behind them. Neurosurgery remains consistently amongst the most competitive medical specialties to obtain entry into.
Main divisions of neurosurgery
General neurosurgery involves most neurosurgical conditions including neuro-trauma and other neuro-emergencies such as intracranial hemorrhage. Most level 1 hospitals have this kind of practice.
Specialized branches have developed to cater to special and difficult conditions. These specialized branches co-exist with general neurosurgery in more sophisticated hospitals. To practice these higher specialization within neurosurgery, additional higher fellowship training of 1–2 years is expected from the neurosurgeon. Some of these divisions of neurosurgery are:
- Vascular and endovascular neurosurgery
- Stereotactic,functional and epilepsy neurosurgery
- Oncological neurosurgery
- Skull-Base Surgery
- Spine neurosurgery
- Peripheral nerve surgery
- Pediatric neurosurgery
The pathology confronted by neurosurgeons could be either congenital, acquired, traumatic, due to infection, or neoplastic or degenerative conditions. Conditions like congenital hydrocephalus, pediatric tumors and myelomeningocele are encountered in children. Trauma with head or spine injury and bleeds due to arteriovenous malformation are encountered in young adults. Degenerative spine disease, aneurysm bleeds and Parkinson's disease are encountered in much older patients. The science of neuropathology is a well developed branch of pathology.
Neuroanesthesia is a highly developed science that is linked to neurosurgery. This branch of medicine plays a very important part in day-to-day neurosurgery.
For a satisfactory neurosurgery outcome a reasonable pre-operative diagnosis is essential. Neuroradiology plays a key role not only in diagnosis but also in the operative phase of neurosurgery.
Neuroradiology methods are used in modern neurosurgery diagnosis and treatment. They include computer assisted imaging computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), magnetoencephalography (MEG), and the stereotactic radiosurgery. Some neurosurgery procedures involve the use of intra-operative MRI and functional MRI.
In conventional open surgery the neurosurgeon opens the skull, uses a large opening to access the brain. Technique of using smaller openings and using microscopes and endoscopes were developed later. With this smaller openings and high clarity microscopic visualization of neural tissue excellent results can be obtained. But, the open methods are still used in trauma or emergency situations Principles of Neurosurgery-Rengachari, Ellenbogen,  Neurotrauma and Critical Care of the Brain-Jallo, Loftus .'
Microsurgery is utilized in many aspects of neurological surgery. Microvascular techniques are used in EC-IC by-pass surgery and in restoration carotid endarterectomy. The clipping of an aneurysm is performed under microscopic vision. Minimally invasive spine surgery utilizes microscopes or endoscopes. Procedures such as microdiscectomy, laminectomy, and artificial disc replacement rely on microsurgery.
Using Stereotaxy neurosurgeons can approach a minute target in the brain through a minimal opening. This is used in functional neurosurgery where electrodes are implanted or gene therapy is instituted with high level of accuracy as in the case of Parkinson's disease or Alzheimer's disease. Then in the combination method of open and stereotactic surgery intraventricular hemorrhages could be evacuated successfully.
Minimally invasive endoscopic surgery is utilized by neurosurgeons. Techniques such as endoscopic endonasal surgery is used in pituitary tumors, craniopharyngiomas, chordomas, and the repair of cerebrospinal fluid leaks. Ventricular endoscopy is used in the treatment of intraventricular bleeds, hydrocephalus, colloid cysts and neurocysticercosis. Endonasal endoscopy at times is carried out with neurosurgeons and ENT surgeons as a team.
Repair of craniofacial disorders and disturbance of cerebrospinal fluid circulation is done by neurosurgeons, and at times teaming up with maxillofacial and plastic surgeons. Cranioplasty for craniosynostosis is performed by pediatric neurosurgeons with or without plastic surgeons.
Neurosurgeons are involved in Stereotactic Radiosurgery along with Radiation Oncologists in tumor and AVM treatmentIntracranial Stereotactic Radiosurgery-Lunsford, Sheehan, Spine Radiosurgery-Gerszten, Ryu. Radiosurgical methods such as Gamma knife, Cyberknife and Novalis Shaped Beam Surgery are used.
Endovascular Neurosurgery utilize endovascular image guided procedures for the treatment of aneurysms, AVMs, carotid stenosis, strokes, and spinal malformations, and vasospasms. Techniques such as angioplasty, stenting, clot retrieval, embolization, and diagnostic angiography are endovascular procedures.
A common procedure performed in neurosurgery is the placement of Ventriculo-Peritoneal Shunt (VP Shunt). In pediatric practice this is for congenital hydrocephalus. The commonest indication in adults is Normal Pressure Hydrocephalus (NPH).
Neurosurgery of the spine covers cervical, thoracic and lumbar spine. Some indications for spine surgery are spinal cord compression from trauma, arthritis or spondylosis. In cervical cord compression patients may have gait difficulty, balance issues, numbness and tingling in hands or feet. Spondylosis is spinal disc degeneration and arthritis that compresses the spinal canal resulting in bone spurring and disc herniation. Power drills and special instruments are used to correct any compression to the spinal canal. Disk herniations of spinal vertebral disks are removed by Kerrison pitiutary rongeurs. This is called a discectomy. Laminectomy is removing Lamina portion of the vertebra of the spine to make room for the compressed nerve tissue. Minimally invasive, radiology assisted spine surgery include vertebroplasty and kyphoplasty where some kinds of spinal fractures are managed Essentials of Spinal Cord Injury-Fehlings, Vaccaro, Boakye et al.
Pain surgery handled by the neurosurgeons include implantation of deep brain stimulators, spinal cord stimulators and pain pumps  Functional Neurosurgery-Starr, Barbaro, Larson. Surgery of the peripheral nervous system include carpal tunnel decompression and peripheral nerve transposition.
Other conditions treated by neurosurgeons include:
- Meningitis and other central nervous system infections including abscesses
- Spinal disc herniation
- Cervical spinal stenosis and Lumbar spinal stenosis
- Head trauma (brain hemorrhages, skull fractures, etc.)
- Spinal cord trauma
- Traumatic injuries of peripheral nerves
- Tumors of the spine, spinal cord and peripheral nerves
- Intracerebral hemorrhage, such as subarachnoid hemorrhage, interdepartmental, and intracellular hemorrhages
- Some forms of drug-resistant epilepsy
- Some forms of movement disorders (advanced Parkinson's disease, chorea) – this involves the use of specially developed minimally invasive stereotactic techniques (functional, stereotactic neurosurgery) such as ablative surgery and deep brain stimulation surgery
- Intractable pain of cancer or trauma patients and cranial/peripheral nerve pain
- Some forms of intractable psychiatric disorders
- Vascular malformations (i.e., arteriovenous malformations, venous angiomas, cavernous angiomas, capillary telangectasias) of the brain and spinal cord
- Moyamoya disease
- Harvey Cushing – known as the father of modern neurosurgery
- Gazi Yaşargil – known as the father of microneurosurgery
- Ludvig Puusepp – known as one of the founding fathers of modern neurosurgery, world's first professor of neurosurgery
- Walter Dandy – known as one of the founding fathers of modern neurosurgery
- Hirotaro Narabayashi – a pioneer of stereotaxic neurosurgery
- Alim-Louis Benabid – known as one of the developers of deep brain stimulation surgery for movement disorder
- Wilder Penfield – known as one of the founding fathers of modern neurosurgery, and pioneer of epilepsy neurosurgery
- Joseph Ransohoff – known for his pioneering use of medical imaging and catheterization in neurosurgery, and for founding the first neurosurgery intensive care unit
- Robert F. Spetzler – The most prolific vascular neurosurgeon in the world and director of the Barrow Neurological Institute
- Lars Leksell – Swedish neurosurgeon who developed the Gamma Knife
- Benjamin Carson – renowned pediatric neurosurgeon at Johns Hopkins Hospital, pioneer in hemispherectomy, and pioneer in the separation of craniopagus twins (joined at the head)
- John R. Adler – Stanford University neurosurgeon who invented the CyberKnife
- Wirginia Maixner – pediatric neurosurgeon at Melbourne's Royal Children's Hospital. Primarily known for separating conjoined Bangladeshi twins, Trishna and Krishna
- Sid Watkins – world renowned neurosurgeon who served for 26 years as the Formula One Safety and Medical Delegate (race doctor)
- Frank Henderson Mayfield – invented the Mayfield skull clamp
- Ayub K. Ommaya – invented the Ommaya reservoir
- American Association of Neurological Surgeons
- Congress of Neurological Surgeons
- Polyaxial screw
- AANS – Patient Information
- "The society of British neurological surgeons". Retrieved 2011-03-11.[dead link]
- Cyber Museum of Neurosurgery
- Stereotactic Radiosurgery Program | UCLA Neurosurgery
- Neuroradiology – Information for Patients & Referring Physicians
- The Brain that Changed Everything by Luke Dittrich – Esquire, November 2010