Neurosurgery is a field which has a poor history. During the early stages, success rates were very poor and mortality rates were high. It was reduced when steroids came in to practice in the fifties. Another landmark was the introduction of operating microscope in the early seventies, which opened the floodgates of micro neurosurgery. This improved the operative field and reduced the risks of the surgery. Technological advancements paved way to new innovations like video recording which made teaching possible. The surgical procedures could be recorded and can be used for teaching purposes also. The new inventions made micro neurosurgery very popular. Other technological landmarks during the same period in imaging and neuroanesthesiology made neurosurgery secure. In the 21st century, the face of neurosurgery has changes entirely and it has been considered as one of the safe and successful field.
Neurosurgery as a specialty is about 150 years old. Prior to that General Surgeons with some interest used to operate on the brain. The invention of X rays by roentgen was a landmark in 1890’s and X rays of the skull wee done to find out some calcifications inside the skull.
Around the same time one American Surgeon called Harvey Cushing took special interest in Neurosurgery and started operating on the brains. He visited many centers in Europe and got fascinated by syphgmomanometer, an instrument developed by Riva Rocci in Italy. He started using it during surgeries to monitor the blood pressure and this paved the way for intra operative monitoring.
Neurosurgical procedures used to be very messy bleeding from the bone and also from the brain. One British Surgeon called Victor Horsley invented a substance called Bone wax, a combination of Bees wax and Phenol that could be used to control the bleeding from the bone. Incidentally he was the first person to remove a spinal cord tumor with very good results. Bone wax is used even now in all surgical procedures were the bone is cut. The introduction of monopolar by Harvey Cushing and subsequently bipolar cautery by Leonard Mallis made control of bleeding from brain very easy. Simultaneously neurology also made rapid progress and neuro physicians started making precise clinical diagnosis. One of the students of Harvey Cushing, Walter Dandy introduced a procedure called Pneumoencephalography, where air was introduced into the cranial cavity and X rays were taken. The air could give a double contrast and it aided in diagnosing neurosurgical conditions. But the outcome was very bad with severe wound infections and brain swelling which resulted in very high mortality. Around 1930’s one French Surgeon, Sicard introduced a procedure called Myelography. Here a contrast medium was introduced into the spinal cavity and X rays were taken. The contrast used to indirectly show tumors and aid in diagnosis.
Around the same time one Spanish Surgeon by name Egaz Moniz developed a procedure called Angiography. Here a contrast medium was injected into the blood vessels and X rays were taken. Tumours and blood clots in the brain could be detected by this procedure indirectly by seeing the shift of blood vessels in the X rays. The contrast medium used to highlight the blood vessels. This was the main modality of investigation for the next 40 odd years. The procedure itself had many side effects and many a time patients used to have huge blood clots at the puncture site in the neck. The contrast medium used was also toxic and many drug reactions used to occur.
1940s’ saw the advent of Sulphonamides and Pencillin and they had a very large role to play in the control of wound infection. The infection rate in all surgeries fell down dramatically and operative results became better, but still neurosurgeons had to battle another condition called brain swelling or brain edema. The nervous tissue used to swell up when handled and this used to produce a lot of morbidity. Steroids were invented in 1950’s and this came as a panacea for all neurosurgeons. Steroid controlled brain edema well and the surgical outcome became much better.
Rapid strides were also being made in the neurology side in the development of medication for epilepsy. They were very useful in the prevention and control of seizures, which were one of the symptoms of intracranial problems. Sixties and Seventies really changed the face of neurosurgery. Many inventions and innovations happened and focus in neurosurgery shifted from less mortality to less morbidity. Since then the outcomes after neurosurgical operations started becoming better. The first innovation was the operating microscope. The introduction of microscope brought many changes in the surgeon’s approach. It combined magnification and illumination and made neurosurgeon’s life easy. Many stalwarts started practicing safe neurosurgery. Prominent among them was Gazi Yasargil. He understood the complex brain anatomy very well using the microscope and introduced many corridors in the brain to reach even the most inaccessible part with very minimal brain injury and swelling. Around the same time video recording was becoming very popular and neurosurgeons across the world started recording their operative procedures and these video records became a very good means of education. The introduction of these videos in the market made knowledge dissemination very easy and even the most reluctant neurosurgeon took to operating microscope. Around the same time some other innovations like 3point head clamp for head fixation and self-retaining retractor system made neurosurgery safer.
The introduction of CT scan in late 1970’s took neurosurgical diagnostic capabilities to new heights. The head injury management took a paradigm shift form wait and watch policy to immediate intervention and helped save many a life. CAT scan was a noninvasive modality and the only side effect was exposure to radiation. The innovation of CT scan sent all the invasive investigation to back seat and investigations for a head problem safer. Around the same time refinements in angiography also started and safer modes like Seldinger’s technique came in to vogue. Through this technique one could enter the vascular tree from an area like groin and any vessel could be entered. The contrast media also became less toxic and investigation related morbidity also became less.
In the late sixties another surgical exercise started becoming popular. It was a direct application of a mathematical concept called coordinate geometry. The surgical concept viewed skull as a sphere and to reach a lesion inside the skull one has to calculate a point of entry from the skull with the help of a frame and a CT scan. This is called Stereotaxy. Deep seated inaccessible lesion like blood clots could be accessed with precision and biopsies of deep seated tumors became possible. This concept was further extended for another area called Functional Neurosurgery, where tremors, Parkinson’s disease etc can be treated. The same principle is also used in some areas of Radiation oncology and is called Stereo tactic Radiotherapy. Here a high volume of radiation dose is focused at a single point in the brain so that side effects of whole brain radiation are avoided.
In eighties another investigative modality was introduced. It is called Magnetic Resonance Imaging. Here there is no radiation involved and a magnet is used to induce sudden change in the flow of water molecules in the body. The lesions are better delineated and many features like Functional MRI, MR spectroscopy have made diagnosis easier. The state of art is having a MRI or CT scan in then operating room and these modes aid in the total excision of the lesions in the brain.
The next development in Neurosurgery in nineties was the concept of Endoscopic Neurosurgery popularly called Keyhole Surgery. The surgical scar became very small and the post-operative stay in the hospital also became less. Using the endoscope one can reach the brain through the nose and this has more acceptance in general population. The next major development is the Endovascular Neurosurgery popularly called Pinhole Surgery. This concept is an application of the principle of angiography. Many problems of the blood vessels in the brain can be treated by this approach and the hospital stay is not more than 24 hours. The explosion of computer also played an important role to make neurosurgery safer. Today we have a concept called Neuronavigation which is a sort of road map. The CT scan and MRI pictures are integrated in a computer and with an instrument called viewing wand one can localize the lesion on the skull and limit the opening to a bare minimum. The brain manipulation also is very less and this results in lesser morbidity. The latest in the innovation is Robotic Neurosurgery. Here robotic arms operate and the surgeons sit in a computer workstation and manipulates the Joystick. The results are very predictable and the concept has taken neurosurgery to newer heights.
With all these technological advances neurosurgery has become very safe.