Stereotactic surgery or
stereotaxy (not to be confused with the virtuality concept of
stereotaxyStereotaxy from stereo meaning solidity, and tactile meaning touch) refers to any technique that involves the recording and reproduction of three-dimensional haptic information or creating an illusion of depth to the sense of touch within an otherwise-flat surface...
) is a minimally-invasive form of
surgicalSurgery is a medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance, or sometimes for some other reason...
intervention which makes use of a three-dimensional coordinates system to locate small targets inside the body and to perform on them some action such as
ablationAblation means removal of material from the surface of an object by vaporization, chipping, or other erosive processes. The term occurs in space physics associated with atmospheric reentry, in glaciology, medicine, and passive fire protection.-Space physics:...
(removal),
biopsyA biopsy is a medical test involving the removal of cells or tissues for examination. It is the removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
,
lesionA lesion is any abnormal tissue found on or in an organism, usually damaged by disease or trauma. Lesion is derived from the Latin word laesio which means injury.-Causes of lesions:...
, injection,
stimulationDeep brain stimulation is a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain...
, implantation,
radiosurgeryRadiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherpy when used to target lesions in the body...
(SRS) etc. "Stereotactic" in Greek (another accepted spelling is "stereotaxic") means "solid ordering".
In theory, any organ system inside the body can be subjected to stereotactic surgery.
Stereotactic surgery or
stereotaxy (not to be confused with the virtuality concept of
stereotaxyStereotaxy from stereo meaning solidity, and tactile meaning touch) refers to any technique that involves the recording and reproduction of three-dimensional haptic information or creating an illusion of depth to the sense of touch within an otherwise-flat surface...
) is a minimally-invasive form of
surgicalSurgery is a medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance, or sometimes for some other reason...
intervention which makes use of a three-dimensional coordinates system to locate small targets inside the body and to perform on them some action such as
ablationAblation means removal of material from the surface of an object by vaporization, chipping, or other erosive processes. The term occurs in space physics associated with atmospheric reentry, in glaciology, medicine, and passive fire protection.-Space physics:...
(removal),
biopsyA biopsy is a medical test involving the removal of cells or tissues for examination. It is the removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
,
lesionA lesion is any abnormal tissue found on or in an organism, usually damaged by disease or trauma. Lesion is derived from the Latin word laesio which means injury.-Causes of lesions:...
, injection,
stimulationDeep brain stimulation is a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain...
, implantation,
radiosurgeryRadiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherpy when used to target lesions in the body...
(SRS) etc. "Stereotactic" in Greek (another accepted spelling is "stereotaxic") means "solid ordering".
In theory, any organ system inside the body can be subjected to stereotactic surgery. Difficulties in setting up a reliable frame of reference (such as
boneBones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
landmarks which bear a constant spatial relation to soft tissues), however, mean that its applications have been limited to
brain surgeryNeurosurgery is the surgery discipline focused on treating the central nervous system, peripheral nervous systems and spinal column diseases amenable to surgical intervention....
. Besides the
brainThe brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all...
, biopsy and surgery of the
breastThe breast is the upper ventral region of an animal’s torso, particularly that of mammals, including human beings. The breasts of a female primate’s body contain the mammary glands, which secrete milk used to feed infants....
are done routinely to locate, sample (biopsy) and remove tissue. Plain X-ray images (
radiographicRadiography is the use of the property of X-rays to cross materials to view inside objects. The impact on society of this technique has also been immense : application fields are medical, non-destructive testing, food inspection, security, archeology, ......
mammography) and
computed tomographyComputed tomography is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.CT...
can be used to guide the procedure.
History
The stereotactic method was first developed by two British scientists in 1908, working at
University College LondonUniversity College London is a British university institution and a constituent college of the University of London, based primarily in Bloomsbury, London...
Hospital, Sir
Victor HorsleySir Victor Alexander Haden Horsley was an accomplished scientist and professor. He was born in Kensington, London. He was educated at Cranbrook School, Kent and studied medicine at University College London and in Berlin, Germany , and in the same year started his career as a house surgeon and...
, a physician and neurosurgeon, and Robert H. Clarke, an engineer. The
Horsley-Clarke apparatusThe Horsley-Clarke apparatus is a device invented in 1908 by British neurosurgeon and scientist Sir Victor A.H. Horsley and his colleague Robert H...
they developed was used for animal experimentation and implemented a Cartesian (three-orthogonal axis) system. Improved designs of their original device came into use in the 1930s for animal experimentation and are still in wide use today in all animal
neuroscienceNeuroscience is the scientific study of the nervous system. Such studies span the structure, function, evolutionary history, development, genetics, biochemistry, physiology, pharmacology, informatics, computational neuroscience and pathology of the nervous system.The International Brain Research...
laboratories.
Using the Horsley-Clarke apparatus for human brains was difficult because of the inability to visualize intracranial anatomic detail via
radiographyRadiography is the use of the property of X-rays to cross materials to view inside objects. The impact on society of this technique has also been immense : application fields are medical, non-destructive testing, food inspection, security, archeology, ......
. However, contrasted brain radiography (particularly pneumoencephalography and ventriculography) permitted the visualization of intracranial anatomic reference points or landmarks. The first stereotactic devices for humans used the
pineal glandThe pineal gland is a small endocrine gland in the vertebrate brain. It produces melatonin, a hormone that affects the modulation of wake/sleep patterns and photoperiodic functions...
and the foramen of Monro as landmarks. Later, other anatomic reference points such as the
anteriorThe Anterior Commissure is a bundle of nerve fibers , connecting the two cerebral hemispheres across the midline, and placed in front of the columns of the fornix...
and
posterior commissureThe posterior commissure is a rounded band of white fibers crossing the middle line on the dorsal aspect of the upper end of the cerebral aqueduct. It is important in the bilateral pupillary light reflex....
s were used as intracranial landmarks. These landmarks were used with a brain atlas to estimate the location of intracranial anatomic structures that were not visible in radiographs.
Using this approach between 1947 and 1949, two American neurosurgeons, Ernest A. Spiegel and Henry T. Wycis, and a Swedish neurosurgeon,
Lars LeksellLars Leksell was a Swedish physician and Professor of Neurosurgery at the Karolinska Institute in Stockholm, Sweden. He was the inventor of radiosurgery.-Life and work:...
, developed the first stereotactic devices that were used for brain surgery in humans. Spiegel and Wycis used the Cartesian coordinate system (also called the translational system) for their device. Leksell's device used the polar coordinate system (also called spherical) that was far easier to use and calibrate in the operating room. The stereotactic localization system was also used by Leksell in his next invention, a device for
radiosurgeryRadiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherpy when used to target lesions in the body...
of the brain. This system is also used by the
Gamma KnifeA gamma knife is a device used to treat brain tumors with a high dose of radiation therapy in one day. The device was invented at the Karolinska Institute in 1967 by Lars Leksell, a Swedish neurosurgeon....
device, and by other neurosurgeons, using linear accelerators, proton beam therapy and neutron capture therapy. Lars Leksell went on to commercialize his inventions by founding
ElektaElekta is a company that provides radiation therapy, radiosurgery, related equipment and clinical management for the treatment of cancer and brain disorders.-History:...
.
In 1978,
Russell A. BrownRussell A. Brown is an American physician and computer scientist. He is the inventor of a method for directing stereotactic surgery using computed tomography....
, an American physician and computer scientist, invented a simple technique to guide stereotactic surgery using
computed tomographyComputed tomography is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.CT...
.
This technique significantly improves surgical precision because computed tomography permits direct visualization of intracranial anatomic detail. The technique uses
fiducial* In law the term "fiducial" means "of or pertaining to a fiduciary".* In imaging technology, a fiduciary marker or fiducial is an object used in the field of view of an imaging system which appears in the image produced, for use as a point of reference or a measure.* "Fiducial" is also used for...
s to create extracranial landmarks in each tomographic image or section. These landmarks specify the spatial orientation of that section with respect to the stereotactic device. Brown's invention stimulated intense interest in stereotaxy and
radiosurgeryRadiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherpy when used to target lesions in the body...
. It is widely used today in the Brown-Roberts-Wells (BRW) stereotactic system as well as other stereotactic and radiosurgical devices.
The stereotactic method has continued to evolve, and at present uses an elaborate mixture of
image-guided surgeryImage-guided surgery is the general term used for any surgical procedure where the surgeon uses indirect visualization to operate, i.e., by employing imaging instruments in real time, such as fiber optic guides, internal video cameras, flexible or rigid endoscopes, ultrasonography, etc...
using
computed tomographyComputed tomography is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.CT...
,
magnetic resonance imagingMagnetic Resonance Imaging , or nuclear magnetic resonance imaging , is primarily a medical imaging technique most commonly used in radiology to visualize the internal structure and function of the body...
and stereotactic localization.
How it works
Stereotactic surgery works on the basis of three main components:
- A stereotactic planning system, including atlas
An atlas is a collection of maps, typically of Earth or a region of Earth, but there are atlases of the other planets in the solar system. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats...
, multimodality image matching tools, coordinates calculator, etc.
- A stereotactic device or apparatus
- A stereotactic localization and placement procedure
Modern stereotactic planning system are computer based. The stereotactic atlas is a series of cross sections of anatomical structure (for example, a human brain), depicted in reference to a two-coordinate frame. Thus, each brain structure can be easily assigned a range of three coordinate numbers, which will be used for positioning the stereotactic device. In most atlases, the three dimensions are: latero-lateral (x), dorso-ventral (y) and rostro-caudal (z).
The stereotactic apparatus uses a set of three coordinates (x, y and z) in an orthogonal frame of reference (cartesian coordinates), or, alternatively, a polar coordinates system, also with three coordinates: angle, depth and antero-posterior location. The mechanical device has head-holding clamps and bars which puts the head in a fixed position in reference to the coordinate system (the so-called zero or origin). In small laboratory animals, these are usually
boneBones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
landmarks which are known to bear a constant spatial relation to soft tissue. For example, brain atlases often use the
external auditory meatusThe ear is the organ that detects sound. The vertebrate ear shows a common biology from fish to humans, with variations in structure according to order and species. It not only acts as a receiver for sound, but plays a major role in the sense of balance and body position...
, the inferior
orbitalEyes are organs that detect light, and send electrical impulses along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system...
ridges, the median point of the
maxillaThe maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes , the maxilla is sometimes called "upper maxilla", with the mandible being the "lower maxilla"...
between the
incisive teethIncisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
. or the
bregmaThe frontal angle is practically a right angle, and corresponds with the point of meeting of the sagittal and coronal sutures; this point is named the bregma. The bregma is known as the anterior fontanelle during infancy. The anterior fontanelle is membranous, and closes within 4-26 months of life....
(confluence of sutures of frontal and parietal bones), as such landmarks. In humans, the reference points, as described above, are intracerebral structures which are clearly discernible in a
radiographRadiography is the use of the property of X-rays to cross materials to view inside objects. The impact on society of this technique has also been immense : application fields are medical, non-destructive testing, food inspection, security, archeology, ......
or tomogram.
Guide bars in the x, y and z directions (or alternatively, in the polar coordinate holder), fitted with high precision
vernier scaleA vernier scale is an additional scale which allows a distance or angle measurement to be read more precisely than directly reading a uniformly-divided straight or circular measurement scale...
s allow the neurosurgeon to position the point of a probe (an
electrodeAn electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit...
, a
cannulaA cannula or canula is a tube that can be inserted into the body, often for the delivery or removal of fluid....
, etc.) inside the brain, at the calculated coordinates for the desired structure, through a small trephined hole in the skull.
Currently, a number of manufacturers produce stereotactic devices fitted for
neurosurgeryNeurosurgery is the surgery discipline focused on treating the central nervous system, peripheral nervous systems and spinal column diseases amenable to surgical intervention....
in humans, as well as for animal experimentation.
Stereotactic radiosurgery (SRS) in cancer treatment
Stereotactic radiosurgery can successfully treat many different types of tumors, both benign and malignant. The malignant brain tumors treated most often are the "brain metastases" or tumors that have spread to the brain. A study in 2008 by the The University of Texas M. D. Anderson Cancer Center indicated that stereotactic radiosurgery (SRS) and whole brain radiation therapy (WBRT) for the treatment of metastatic brain tumours have more than twice the risk of developing learning and memory problems than those treated with SRS alone.
“While both approaches are in practice and both are equally acceptable, data from this study suggest that oncologists should offer SRS alone as the upfront, initial therapy for patients with up to three brain metastases,” Three of the latest radiosurgery treatments, are
CyberKnifeThe CyberKnife is a frameless robotic radiosurgery system invented by John R. Adler a Stanford University Professor of Neurosurgery and Radiation Oncology and Peter and Russell Schonberg of Schonberg Research Corporation, The two main elements of the CyberKnife are the radiation produced from a...
,
Gamma KnifeA gamma knife is a device used to treat brain tumors with a high dose of radiation therapy in one day. The device was invented at the Karolinska Institute in 1967 by Lars Leksell, a Swedish neurosurgeon....
and the Stereotactic Linear Accelerator with Image Guided Radiotherapy, Respiratory Gating, Cone beam CT, Kv Imaging and RapidArc.
See also
- Cyberknife
The CyberKnife is a frameless robotic radiosurgery system invented by John R. Adler a Stanford University Professor of Neurosurgery and Radiation Oncology and Peter and Russell Schonberg of Schonberg Research Corporation, The two main elements of the CyberKnife are the radiation produced from a...
- Gamma knife
A gamma knife is a device used to treat brain tumors with a high dose of radiation therapy in one day. The device was invented at the Karolinska Institute in 1967 by Lars Leksell, a Swedish neurosurgeon....
- Interventional radiology
Interventional Radiology is a subspecialty of radiology in which minimally invasive procedures are performed using image guidance. Some of these procedures are done for purely diagnostic purposes , while others are done for treatment purposes...
- Novalis radiosurgery
- Psychosurgery
Psychosurgery is a subset of neurosurgery intended to modulate the performance of the brain, and thus effect changes in cognition, with the intent to treat or alleviate severe mental illness...
- Radiosurgery
Radiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherpy when used to target lesions in the body...
- Stereotaxic atlas
Stereotaxic atlas is a number of records of brain structure of a particular animal accompanied with coordinates used in stereotactic surgery.-External links:**...
External links