What does T1 and T2 mean on MRI?
The most common MRI sequences are T1-weighted and T2-weighted scans. T1-weighted images are produced by using short TE and TR times. The contrast and brightness of the image are predominately determined by T1 properties of tissue. Conversely, T2-weighted images are produced by using longer TE and TR times.
What does T1 and T2 represent?
T1 and T2 are technical terms applied to different MRI methods used to generate magnetic resonance images. Specifically, T1 and T2 refers to the time taken between magnetic pulses and the image is taken. These different methods are used to detect different structures or chemicals in the central nervous system.
What does low T1 and T2 signal mean?
T1 weighted image – Pathology (spine) Loss of the normal high signal in the bone marrow indicates loss of normal fatty tissue and increased water content. Abnormal low signal on T1 images frequently indicates a pathological process such as trauma, infection, or cancer.
What is T1 and T2 hyperintense?
Abstract. T1 -hypointense lesions (T1-black holes) in multiple sclerosis (MS) are areas of relatively severe central nervous system (CNS) damage compared with the more non-specific T2-hyperintense lesions, which show greater signal intensity than normal brain on T2-weighted magnetic resonance imaging (MRI).
What does T2 mean in medical terms?
An MRI term for the time constant for the loss of phase coherence among spins oriented at an angle to the static magnetic field, which is due to a combination of magnetic field inhomogeneities and spin-spin relaxation, resulting in a rapid loss of transverse magnetisation and the MRI signal.
What is the relationship between T1 and T2?
T2 progressively increases with molecular tumbling rate. In the limit (pure liquids like CSF) T1=T2 and both are several seconds in length. The overall T1 effect can be thought of as a “Goldilock’s” phenomenon.
What is a T1 T2 hypointense lesion?
T1 lesions were defined as regions with a signal intensity similar to or reduced to the signal intensity of gray matter and corresponding to a hyperintense region on T2-weighted MRI. Hyperintense–T2 lesions were defined as sharply demarcated regions of high signal intensity compared with surrounding brain tissue.
What does T1 stand for in medical terms?
T1-T12 (thoracic vertebrae): The symbols T1 through T12 represent the 12 thoracic vertebrae. The thoracic vertebrae are situated between the cervical (neck) vertebrae and the lumbar vertebrae.
What does increased T2 signal mean on MRI?
An increase in T2 signal intensity is often associated with chronic compression of the spinal cord, and it is well established that chronic compression results in structural changes to the spinal cord.
What does T1 hyperintense lesion mean?
T1 signal hyperintensity may correspond to intracellular and extracellular methemoglobin. It may also be seen during the chronic stage of a clot or hemorrhage, when sedimentation of the blood cells produces a distinctive fluid-debris level within the lesion.