The supratentorial area is the upper part of the brain and the infratentorial area is the lower back part of the brain. White matter is the brain tissue that contains nerve fibers and serves as the connection to other parts of the brain. White matter hyperintensities are areas with high water or protein content that show up bright and are common changes seen on MRI in asymptomatic individuals (those with no symptoms). Their prevalence increases with age, to nearly 100% in those older than 90 years. The possible causes of white matter hyperintensities include chronic microvascular ischemic changes, vasculitis (blood vessel inflammation), migraine, Lyme disease or (less likely) demyelinating disease.
White matter is the brain tissue that contains nerve fibers and serves as the connection to other parts of the brain. It is found in the subcortical (deeper) tissues of the brain. Nonspecific (meaning it is difficult to say what caused it) T2 hyperintensities describe areas with high water or protein content that show up “bright” (hyperintense) on certain MRI sequences. White matter hyperintensities are common changes seen on MRI in asymptomatic individuals (those with no symptoms), and their prevalence increases with age, to nearly 100% in those older than 90 years. They might be simply a benign (non-cancerous) marker of aging or they could be a marker of small vessel disease which is associated with cognition and stroke. Modifiable risk factors of small vessel disease include smoking, high blood pressure, poor cholesterol levels, carotid artery disease, and atrial fibrillation.
Spondylolisthesis is a general term when the vertebra (spinal bone) is out of position relative to the other vertebrae. Spondylolisthesis occurs most often after age 40 because of degenerative wear-and-tear. Symptoms, if any, usually correlate with the grade of vertebral slippage, and can include localized pain, decreased range of motion, and numbness or tingling. If the slippage is in the lower back the pain may spread across the lower back and/or radiate to the buttocks and to the back of the thighs, and may feel like a muscle strain. It can also cause spasms in the hamstring muscles.
Retrolisthesis is when there is backward slipping of the vertebra (spinal bone.) Retrolistheis occurs most often after age 40 because of degenerative wear-and-tear. Symptoms, if any, usually correlate with the grade of vertebral slippage, and can include localized pain, decreased range of motion, and numbness or tingling. If the slippage is in the lower back the pain may spread across the lower back and/or radiate to the buttocks and to the back of the thighs, and may feel like a muscle strain. It can also cause spasms in the hamstring muscles.
Brain tissue tends to shrink at the rate of about 0.2% per year after age 30 and then accelerates after the age of 60, due to genetic, environmental, and lifestyle factors.
Within the brain, there are two (right and left) C-shaped structures called “lateral ventricles” that produce and contain cerebrospinal fluid (a clear, watery fluid that helps cushion the brain, circulate nutrients and remove waste). Asymmetric lateral ventricles (difference in ventricle size) may form during fetal development, and is a normal anatomic variant in 5-20% of people. Other known causes of asymmetric lateral ventricles include trauma, a lesion within the ventricle space, recent stroke and bleeding within the brain.Asymptomatic (does not cause symptoms) asymmetric lateral ventricles do not require further evaluation or management. Asymmetric lateral ventricles can cause symptoms that include headaches, seizure activity, a temporary blockage of blood flow to the brain (transient ischemic attacks), and have been associated with certain neuropsychiatric conditions such as schizophrenia
