White matter foci commonly appear on a magnetic resonance imaging (MRI) as bright white spots on the part of the brain that contains nerve cells covered with lipid tissue known as myelin. The foci typically represent areas with higher levels of fluid. The bright spots usually indicate physiological changes caused by disease processes, infections, or the normal aging process. Individuals with white matter foci may or may not exhibit physical symptoms.
Individuals often equate these bright spots with the potential diagnosis of multiple sclerosis (MS) or brain tumors, but this is not necessarily the case. Physicians evaluate white matter foci based on a patient’s physical symptoms, the location and size of the lesions, and information gained from other tests. Proper diagnosis may require the opinion of radiologists, neurologists, or other specialists combined with a series of bodily fluid tests and physical exams.
Multiple sclerosis involves the deterioration of the myelin sheath, which an MRI scan depicts as white matter foci in various parts of the brain. Patients with MS usually complain of visual disturbances along with numbness or weakness in the extremities. Physicians make a definitive diagnosis based on the MRI, spinal fluid tap, and extensive visual testing. Health care providers usually order MRIs over a period of time, checking for an increased number of white matter foci and the location of plaque development.
Patients with bacterial, fungal, or viral encephalitis commonly exhibit white matter foci on MRI scans. These areas typically indicate abscesses or vascular inflammation. Patients generally report having had an infection or experiencing physical symptoms that necessitate the imaging studies. Diagnosis and treatment usually requires organism identification through blood and urine samples, spinal tap, and sensitivity cultures.
Brain tumors and post-stroke hemorrhage frequently appear as white matter foci. MRIs with contrast media generally further indicate specific vascular involvement. Patients with either diagnosis generally experience physical symptoms prompting the imaging studies. Tumor treatment depends on whether the lesion is benign or malignant, its size, and its location. Treatment for lesions that appear secondary to a stroke depend on whether a vessel is blocked or ruptured and whether it is accessible.
Patients diagnosed with hypertension, diabetes, or high cholesterol often have white matter foci. These areas generally represent restricted blood flow in the brain’s capillaries. These lesions frequently appear as individuals get older. In most instances, these patients remain without physical symptoms. Physicians generally prescribe medication for the underlying cause and follow up as needed. White matter foci have also been discovered in patients with a history of migraines.
