Bilateral cingulotomy
Encyclopedia
Bilateral cingulotomy is a form of psychosurgery
, introduced in 1948 as an alternative to lobotomy
. Today, it is mainly used in the treatment of obsessive-compulsive disorder
, depression and addiction
. It is also, rarely, used in the treatment of chronic pain. The objective of this surgical procedure is the severing of the supracallosal fibres of the cingulum bundle, which pass through the anterior cingulate gyrus.
, which is a part of the limbic system
. This system is responsible for the integration of feelings and emotion in the human cortex
. It consists of the cingulate gyrus, parahippocampal gyrus
and the hippocampal formation
.
Studies in patients that were a subject to bilateral cingulotomy, that involved fMRI analyses, showed that the anterior cingulate cortex
has a key role in cognitive control and is highly likely to be involved in the control of attentional response, whereas the dorsal part of that region of the brain was not identified to be involved in such a process, although this is still under dispute. The function of the dorsal part of the cingulate cortex was connected to the sorting out and processing of conflicting information signals. In addition, neuroimaging
studies also indicated that the anterior cingulate cortex participates in the modulation of cortical
regions that are of higher order as well as sensory processing areas.
These findings have also been confirmed by stereotactic microelectrode analysis of single cortical neurons in a study, which involved nine patients undergoing bilateral cingulotomy. The study investigated the effect of performing attention demanding tasks on the activity of 36 neurons located in the anterior cingulate cortex
. Upon analyzing of the results of the study it was concluded that the anterior cingulate cortex is indeed involved in the modification of cognitive tasks that require attention based on the fact that there was a change in the basal firing rate of neurons in that region during simulation of such tasks.
Neuroimaging also uncovered different sub-regions in the anterior cingulate cortex
itself based on their function. It was proven that the caudal part of the anterior cingulate cortex plays a more important function in cognitive activities that involve attention, salience, interference and response competition. These results combined with electrophysiological investigation of the function of neurons in the anterior cingulate cortex have provided insights that can be used in the improvement of cingulotomy performed on patients treated for OCD. The basis behind this idea is the fact that a variation of certain tasks, Emotional Stroop tasks (ES), which have been particularly identified as exerting effects in OCD patients activate neurons in the more rostral part of the anterior cingulate cortex. Thus, theoretically if bilateral cingulotomy is performed in such patient in the rostral anterior cingulate cortex, better results should be obtained.
Moreover, OCD has been associated with a malformation of the basal ganglia
. The function of this part of the human brain has been mapped to be composed of fiber tracks associated with numerous parallel cortico-striato-thalamocortical circuits (CSTC), which are involved in sensorimotor, motor
, oculomotor as well as the cognitive processes that are manifested by the limbic system
. This pathway involves GABAergic inhibitory projections that serve as one of the means of communication between the different structures involved. It has been hypothesized that some forms of OCD are a result of disinhibition of a one or several of the circuits that operate in the CSTC. This is also indicated by a finding that showed a significant decrease in intracortical in OCD patients. Thus, lesions in the anterior cingulate cortex
might contribute to the lessening of the disinhibition effect.
This theory has been confirmed by another study which assessed the cortical
inhibitory and excitatory mechanisms in OCD. The study measured the excitability of motor cortex
, as well as intracortical inhibition in OCD patients and a control of healthy individuals. The results showed a significant decrease in intracortical inhibition, which resulted in a slowdown of interstimulus intervals by 3msec.
In addition to its proximity to and association with the limbic system and the amygdala
in particular, which plays a key role in emotional experience, the anterior cingulate cortex shares afferent
and efferent pathways with a number of thalamic nuclei as well as the posterior cingulate
and part of some parietal
, frontal
and supplementary motor cortex. All these underline the high likelihood that the anterior cingulate cortex must be linked to OCD.
Functional MRI analyses of the anterior cingulate cortex
have also led to the introduction of bilateral cingulotomy for the treatment of chronic pain
. Such application was introduced since the anterior cingulate cortex has been found to be related to the processing nociceptive information input. In particular the role of the anterior cingulate cortex is in the interpretation of how a stimulus
affects a person rather than its actual physical intensity.
images of the brain of the patient. This step ensures that the exact target, the cingulate cortex
is mapped out, so that the surgeon can identify it. Then burr holes are created into the patient’s skull
using a drill. Lesions at the targeted tissue are made with the help of fine electrodes inserted very carefully at the right angle into the subject’s brain based on plotting charts and making sure important arteries and blood vessels are intact. The electrode is placed in a , or a holder, with only its tip projecting. Upon the correct insertion of the holder into the brain tissue, air is injected and more scan images are taken. Then, after the medical team has made sure they are on the right track, the tip of the electrode is advanced to the plane of the cingulate where it is heated to 75-90 C. Once the first lesion is created it serves as a center around which several other lesions are created. In order to confirm whether lesions are made at the right place, images are taken postoperatively and analyzed.
Recent technological advances, however, have made bilateral cingulotomy a more precise operation. For example, nowadays a neurosurgical team that has to perform the procedure can use an MRI to identify the location of the anterior and posterior commissure
s. This approach allows neurosurgeons to obtain a number of coronal images, which are then used to calculate the stereotactic coordinates of the place in the anterior cingulate cortex
, where lesions need to be created. Moreover the MRI enables to differentiate more precisely the cell composition, and thus easily identify the gray matter
in that region. This can then be further confirmed with the help of microelectrode recordings.
, vomiting
, and headaches. However, in some cases patients exhibit seizures that sometimes appear up to two months after the surgical intervention. There is the discussion as to whether this is relevant and can be account to cingulotomy because such seizures were observed in patients that already had a history of this condition.
analyzed the outcome of bilateral cingulotomy in 44 patients for the treatment of OCD in the period between 1965 and 1986. Patients were followed up over a long term and evaluated based on several criteria: 1) how many of them were responders after a period of 6 months, 2) how many cingulotomies had a patient undergone before the examination of the effectiveness of the procedure, 3) did the patient show any significant change after the most recent procedure and 4) what were the side effects related to the procedure.
The follow up of the patients produced contradictory results, which indicated that bilateral cingulotomy is not the optimal treatment for OCD as of today. From the 44 patients only 32% could be classified as responders and showed significant improvement compared to the other subjects. Another 14% exhibited some signs of improvement. Multiple cingultomies lead to the increase in responders by 6% and to partial responders by 11%. However, the side effects associated with the procedure were numerous. Among the complaints that patients had after the surgery were deficits in memory and apathy
although these were rarely observed. In addition, some of the subjects complained from some form of urinary disturbance ranging from urinary retention
to incontinence
. Hydrocephalus
(2%) and seizures (2%) were also observed .
Another clinical study investigated the effect of bilateral cingulotomy for the treatment of refractory
chronic pain
. In this case 23 patients that were subject to 28 cingulotomies in total were followed up. The analyses aimed at determining how much the pain of each individual was affected after the procedure with the help of a questionnaire. In addition, the examiners tried to evaluate the social and family relations of the participants in the study. Based on the data obtained, cingulatomy for treatment of chronic pain showed promising results. 72% reported improvement in the level of pain experienced, and 50 % indicated that they no longer required painkillers after cingulotomy. More than half of the patients also claimed that the surgical procedure was beneficial and contributed to the improvement of their social aspects.
Psychosurgery
Psychosurgery, also called neurosurgery for mental disorder , is the neurosurgical treatment of mental disorder. Psychosurgery has always been a controversial medical field. The modern history of psychosurgery begins in the 1880s under the Swiss psychiatrist Gottlieb Burckhardt...
, introduced in 1948 as an alternative to lobotomy
Lobotomy
Lobotomy "; τομή – tomē: "cut/slice") is a neurosurgical procedure, a form of psychosurgery, also known as a leukotomy or leucotomy . It consists of cutting the connections to and from the prefrontal cortex, the anterior part of the frontal lobes of the brain...
. Today, it is mainly used in the treatment of obsessive-compulsive disorder
Obsessive-compulsive disorder
Obsessive–compulsive disorder is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear, or worry, by repetitive behaviors aimed at reducing the associated anxiety, or by a combination of such obsessions and compulsions...
, depression and addiction
Addiction
Historically, addiction has been defined as physical and psychological dependence on psychoactive substances which cross the blood-brain barrier once ingested, temporarily altering the chemical milieu of the brain.Addiction can also be viewed as a continued involvement with a substance or activity...
. It is also, rarely, used in the treatment of chronic pain. The objective of this surgical procedure is the severing of the supracallosal fibres of the cingulum bundle, which pass through the anterior cingulate gyrus.
Target
Bilateral Cingulotomy targets the anterior cingulate cortexAnterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
, which is a part of the limbic system
Limbic system
The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...
. This system is responsible for the integration of feelings and emotion in the human cortex
Cortex (anatomy)
In anatomy and zoology the cortex is the outermost layer of an organ. Organs with well-defined cortical layers include kidneys, adrenal glands, ovaries, the thymus, and portions of the brain, including the cerebral cortex, the most well-known of all cortices.The cerebellar cortex is the thin gray...
. It consists of the cingulate gyrus, parahippocampal gyrus
Parahippocampal gyrus
The parahippocampal gyrus is a grey matter cortical region of the brain that surrounds the hippocampus. This region plays an important role in memory encoding and retrieval....
and the hippocampal formation
Hippocampal formation
The hippocampal formation is a compound structure in the medial temporal lobe of the brain. There is currently no consensus concerning which brain regions are encompassed by the term, with some authors defining it as the dentate gyrus, the hippocampus proper and the subiculum; and others including...
.
Studies in patients that were a subject to bilateral cingulotomy, that involved fMRI analyses, showed that the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
has a key role in cognitive control and is highly likely to be involved in the control of attentional response, whereas the dorsal part of that region of the brain was not identified to be involved in such a process, although this is still under dispute. The function of the dorsal part of the cingulate cortex was connected to the sorting out and processing of conflicting information signals. In addition, neuroimaging
Neuroimaging
Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function/pharmacology of the brain...
studies also indicated that the anterior cingulate cortex participates in the modulation of cortical
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
regions that are of higher order as well as sensory processing areas.
These findings have also been confirmed by stereotactic microelectrode analysis of single cortical neurons in a study, which involved nine patients undergoing bilateral cingulotomy. The study investigated the effect of performing attention demanding tasks on the activity of 36 neurons located in the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
. Upon analyzing of the results of the study it was concluded that the anterior cingulate cortex is indeed involved in the modification of cognitive tasks that require attention based on the fact that there was a change in the basal firing rate of neurons in that region during simulation of such tasks.
Neuroimaging also uncovered different sub-regions in the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
itself based on their function. It was proven that the caudal part of the anterior cingulate cortex plays a more important function in cognitive activities that involve attention, salience, interference and response competition. These results combined with electrophysiological investigation of the function of neurons in the anterior cingulate cortex have provided insights that can be used in the improvement of cingulotomy performed on patients treated for OCD. The basis behind this idea is the fact that a variation of certain tasks, Emotional Stroop tasks (ES), which have been particularly identified as exerting effects in OCD patients activate neurons in the more rostral part of the anterior cingulate cortex. Thus, theoretically if bilateral cingulotomy is performed in such patient in the rostral anterior cingulate cortex, better results should be obtained.
Moreover, OCD has been associated with a malformation of the basal ganglia
Basal ganglia
The basal ganglia are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus and other brain areas...
. The function of this part of the human brain has been mapped to be composed of fiber tracks associated with numerous parallel cortico-striato-thalamocortical circuits (CSTC), which are involved in sensorimotor, motor
Motor system
The motor system is the part of the central nervous system that is involved with movement. It consists of the pyramidal and extrapyramidal system....
, oculomotor as well as the cognitive processes that are manifested by the limbic system
Limbic system
The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...
. This pathway involves GABAergic inhibitory projections that serve as one of the means of communication between the different structures involved. It has been hypothesized that some forms of OCD are a result of disinhibition of a one or several of the circuits that operate in the CSTC. This is also indicated by a finding that showed a significant decrease in intracortical in OCD patients. Thus, lesions in the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
might contribute to the lessening of the disinhibition effect.
This theory has been confirmed by another study which assessed the cortical
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
inhibitory and excitatory mechanisms in OCD. The study measured the excitability of motor cortex
Motor cortex
Motor cortex is a term that describes regions of the cerebral cortex involved in the planning, control, and execution of voluntary motor functions.-Anatomy of the motor cortex :The motor cortex can be divided into four main parts:...
, as well as intracortical inhibition in OCD patients and a control of healthy individuals. The results showed a significant decrease in intracortical inhibition, which resulted in a slowdown of interstimulus intervals by 3msec.
In addition to its proximity to and association with the limbic system and the amygdala
Amygdala
The ' are almond-shaped groups of nuclei located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.-...
in particular, which plays a key role in emotional experience, the anterior cingulate cortex shares afferent
Afferent
Afferent is an anatomical term with the following meanings:*Conveying towards a center, for example the afferent arterioles conveying blood towards the Bowman's capsule in the Kidney. Opposite to Efferent.*Something that so conducts, see Afferent nerve fiber...
and efferent pathways with a number of thalamic nuclei as well as the posterior cingulate
Posterior cingulate
The posterior cingulate cortex is the backmost part of the cingulate cortex, lying behind the anterior cingulate cortex.This is the upper part of the "limbic lobe". The cingulate cortex is made up of an area around the midline of the brain...
and part of some parietal
Parietal lobe
The parietal lobe is a part of the Brain positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different modalities, particularly determining spatial sense and navigation. For example, it comprises somatosensory cortex and the...
, frontal
Frontal lobe
The frontal lobe is an area in the brain of humans and other mammals, located at the front of each cerebral hemisphere and positioned anterior to the parietal lobe and superior and anterior to the temporal lobes...
and supplementary motor cortex. All these underline the high likelihood that the anterior cingulate cortex must be linked to OCD.
Functional MRI analyses of the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
have also led to the introduction of bilateral cingulotomy for the treatment of chronic pain
Chronic pain
Chronic pain has several different meanings in medicine. Traditionally, the distinction between acute and chronic pain has relied upon an arbitrary interval of time from onset; the two most commonly used markers being 3 months and 6 months since the initiation of pain, though some theorists and...
. Such application was introduced since the anterior cingulate cortex has been found to be related to the processing nociceptive information input. In particular the role of the anterior cingulate cortex is in the interpretation of how a stimulus
Stimulus (physiology)
In physiology, a stimulus is a detectable change in the internal or external environment. The ability of an organism or organ to respond to external stimuli is called sensitivity....
affects a person rather than its actual physical intensity.
Procedure
In most cases the procedure starts with the medical team taking a number of CT scan X-rayX-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
images of the brain of the patient. This step ensures that the exact target, the cingulate cortex
Cingulate cortex
The cingulate cortex is a part of the brain situated in the medial aspect of the cortex. It includes the cortex of the cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the cingulate sulcus...
is mapped out, so that the surgeon can identify it. Then burr holes are created into the patient’s skull
Human skull
The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...
using a drill. Lesions at the targeted tissue are made with the help of fine electrodes inserted very carefully at the right angle into the subject’s brain based on plotting charts and making sure important arteries and blood vessels are intact. The electrode is placed in a , or a holder, with only its tip projecting. Upon the correct insertion of the holder into the brain tissue, air is injected and more scan images are taken. Then, after the medical team has made sure they are on the right track, the tip of the electrode is advanced to the plane of the cingulate where it is heated to 75-90 C. Once the first lesion is created it serves as a center around which several other lesions are created. In order to confirm whether lesions are made at the right place, images are taken postoperatively and analyzed.
Recent technological advances, however, have made bilateral cingulotomy a more precise operation. For example, nowadays a neurosurgical team that has to perform the procedure can use an MRI to identify the location of the anterior and posterior commissure
Commissure
A commissure is the place where two things are joined. The term is used especially in the fields of anatomy and biology.In anatomy, commissure refers to a bundle of nerve fibers that cross the midline at their level of origin or entry .* The most common usage of the term refers to the brain's...
s. This approach allows neurosurgeons to obtain a number of coronal images, which are then used to calculate the stereotactic coordinates of the place in the anterior cingulate cortex
Anterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
, where lesions need to be created. Moreover the MRI enables to differentiate more precisely the cell composition, and thus easily identify the gray matter
Gray Matter
"Gray Matter" is a short story by Stephen King, first published in the October 1973 issue of Cavalier magazine, and later collected in King's 1978 collection Night Shift. It is set in the same area as King's novel Dreamcatcher.-Setting:...
in that region. This can then be further confirmed with the help of microelectrode recordings.
Side Effects
Patients usually recover from this operation over a period of 4 days. However, there are cases of subjects released from hospital after as few as 48 hours after the operation. The mild shorter postoperative complications that are most commonly related to bilateral cingulotomy are typical of head interventions and include but are not limited to nauseaNausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
, vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
, and headaches. However, in some cases patients exhibit seizures that sometimes appear up to two months after the surgical intervention. There is the discussion as to whether this is relevant and can be account to cingulotomy because such seizures were observed in patients that already had a history of this condition.
Case Studies
A recent study conducted at the Massachusetts General HospitalMassachusetts General Hospital
Massachusetts General Hospital is a teaching hospital and biomedical research facility in the West End neighborhood of Boston, Massachusetts...
analyzed the outcome of bilateral cingulotomy in 44 patients for the treatment of OCD in the period between 1965 and 1986. Patients were followed up over a long term and evaluated based on several criteria: 1) how many of them were responders after a period of 6 months, 2) how many cingulotomies had a patient undergone before the examination of the effectiveness of the procedure, 3) did the patient show any significant change after the most recent procedure and 4) what were the side effects related to the procedure.
The follow up of the patients produced contradictory results, which indicated that bilateral cingulotomy is not the optimal treatment for OCD as of today. From the 44 patients only 32% could be classified as responders and showed significant improvement compared to the other subjects. Another 14% exhibited some signs of improvement. Multiple cingultomies lead to the increase in responders by 6% and to partial responders by 11%. However, the side effects associated with the procedure were numerous. Among the complaints that patients had after the surgery were deficits in memory and apathy
Apathy
Apathy is a state of indifference, or the suppression of emotions such as concern, excitement, motivation and passion. An apathetic individual has an absence of interest in or concern about emotional, social, spiritual, philosophical or physical life.They may lack a sense of purpose or meaning in...
although these were rarely observed. In addition, some of the subjects complained from some form of urinary disturbance ranging from urinary retention
Urinary retention
Urinary retention, also known as ischuria, is a lack of ability to urinate. It is a common complication of benign prostatic hyperplasia , although it can also be caused by nerve dysfunction, constipation, infection, or medications...
to incontinence
Urinary incontinence
Urinary incontinence is any involuntary leakage of urine. It is a common and distressing problem, which may have a profound impact on quality of life. Urinary incontinence almost always results from an underlying treatable medical condition but is under-reported to medical practitioners...
. Hydrocephalus
Hydrocephalus
Hydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...
(2%) and seizures (2%) were also observed .
Another clinical study investigated the effect of bilateral cingulotomy for the treatment of refractory
Refractory
A refractory material is one that retains its strength at high temperatures. ASTM C71 defines refractories as "non-metallic materials having those chemical and physical properties that make them applicable for structures, or as components of systems, that are exposed to environments above...
chronic pain
Chronic pain
Chronic pain has several different meanings in medicine. Traditionally, the distinction between acute and chronic pain has relied upon an arbitrary interval of time from onset; the two most commonly used markers being 3 months and 6 months since the initiation of pain, though some theorists and...
. In this case 23 patients that were subject to 28 cingulotomies in total were followed up. The analyses aimed at determining how much the pain of each individual was affected after the procedure with the help of a questionnaire. In addition, the examiners tried to evaluate the social and family relations of the participants in the study. Based on the data obtained, cingulatomy for treatment of chronic pain showed promising results. 72% reported improvement in the level of pain experienced, and 50 % indicated that they no longer required painkillers after cingulotomy. More than half of the patients also claimed that the surgical procedure was beneficial and contributed to the improvement of their social aspects.