Clinically isolated syndrome
Encyclopedia
A clinically isolated syndrome (CIS) is an individual's first neurological
episode, caused by inflammation
or demyelination of nerve
tissue. An episode may be monofocal, in which symptom
s present at a single site in the central nervous system
, or multifocal, in which multiple sites exhibit symptoms.
Brain lesions associated with clinically isolated syndrome may be indicative of multiple sclerosis
(MS). In order for such a diagnosis, multiple sites in the central nervous system must present lesions, typically over multiple episodes, and for which no other diagnosis is likely. A clinically definitive diagnosis of MS is made once an MRI
detects lesions in the brain, consistent with those typical of MS. Other diagnostics include cerebrospinal fluid
analysis and evoked response testing.
In 2001, the International Panel on the Diagnosis of Multiple Sclerosis issued the McDonald criteria
, a revision of the previous diagnostic procedures to detect MS, known as the Poser criteria
. "While maintaining the basic requirements of dissemination in time and space, the McDonald criteria provided specific guidelines for using findings on MRI and cerebrospinal fluid analysis to provide evidence of the second attack in those individuals who have had a single demyelinating episode and thereby confirm the diagnosis more quickly." Further revisions were issued in 2005.
Neurology
Neurology is a medical specialty dealing with disorders of the nervous system. Specifically, it deals with the diagnosis and treatment of all categories of disease involving the central, peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue,...
episode, caused by inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
or demyelination of nerve
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
tissue. An episode may be monofocal, in which symptom
Symptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
s present at a single site in the central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
, or multifocal, in which multiple sites exhibit symptoms.
Brain lesions associated with clinically isolated syndrome may be indicative of multiple sclerosis
Multiple sclerosis
Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...
(MS). In order for such a diagnosis, multiple sites in the central nervous system must present lesions, typically over multiple episodes, and for which no other diagnosis is likely. A clinically definitive diagnosis of MS is made once an MRI
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
detects lesions in the brain, consistent with those typical of MS. Other diagnostics include cerebrospinal fluid
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
analysis and evoked response testing.
In 2001, the International Panel on the Diagnosis of Multiple Sclerosis issued the McDonald criteria
McDonald criteria
The McDonald criteria are diagnostic criteria for multiple sclerosis . These criteria are named after neurologist W. Ian McDonald. In April 2001 an international panel in association with the National Multiple Sclerosis Society of America recommended revised diagnostic criteria for MS...
, a revision of the previous diagnostic procedures to detect MS, known as the Poser criteria
Poser criteria
Poser criteria are diagnostic criteria for multiple sclerosis . They replaced the older Schumacker criteria, and now they are considered obsolete as McDonald criteria have superseded them...
. "While maintaining the basic requirements of dissemination in time and space, the McDonald criteria provided specific guidelines for using findings on MRI and cerebrospinal fluid analysis to provide evidence of the second attack in those individuals who have had a single demyelinating episode and thereby confirm the diagnosis more quickly." Further revisions were issued in 2005.