What is a hypointense lesion?
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 is a T2 hypointense lesion?
T2 heterogeneous hypointense or mixed signal solid lesions have intermediate signal or T2 inhomogeneous signal with a mixture of T2 low and bright signal (higher than that of the outer myometrium or skeletal muscle). These may represent either benign or malignant lesions, either primary or secondary 3, 8.
What is a hypointense nodule?
Non-hypervascular HBPI hypointense nodules were defined as solid nodules with low signal intensity on HBPI, while not showing higher signal intensity than that of the spleen on heavily T2WI.
What is a T2 hypointense nodule?
Adnexal lesions that are hypointense on T2-weighted MR images, but whose signal intensity is higher than that of skeletal muscle, are a more heterogeneous group composed of benign, borderline, and malignant disease entities.
Can a lesion be a tumor?
By definition, tumor and tumor-like lesions are lesions that look alike on ultrasound (US), computer tomography (CT) or magnetic resonance imaging (MRI) studies. Typically, tumor-like lesions are reported as: findings compatible with a tumor-like lesion, however neoplasm cannot be ruled out.
What does hypointense marrow signal mean?
Lymphoma within marrow is characterized by hypointense T1 and T2 signal of involved portions of the bone marrow which enhance, a nonspecific pattern common to many of the infiltrative and replacement diseases.
What is hypointense on T1 and T2?
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 hypointense mean in medical terms?
A hyperintensity is an area that appears lighter in color than the surrounding tissues; a hypointensity would be darker in color. When we’re talking about hyperintensities as seen on MRI, in the context of MS, we are talking about lesions, most commonly white matter lesions.
What does T1 hyperintensity mean?
Hyperintense cerebral changes on T1-weighted images are formed due to accumulation of substances characterized by short longitudinal relaxation time including: gadolinium contrast, intra- and extracellular methemoglobin, melanin, fatty and protein-rich substances and minerals, i.a. calcium, copper and manganese.
What does hypointense mean on MRI?
Often we refer to the appearance by relative terms: hyperintense = brighter than the thing we are comparing it to. isointense = same brightness as the thing we are comparing it to. hypointense = darker than the thing we are comparing it to.
What are the 3 types of lesions?
They tend to be divided into three types of groups: Skin lesions formed by fluid within the skin layers, such as vesicles or pustules. Skin lesions that are solid, palpable masses, such as nodules or tumors. Flat, non-palpable skin lesions like patches and macules.
What’s the difference between a tumor and a lesion?
A bone lesion is considered a bone tumor if the abnormal area has cells that divide and multiply at higher-than-normal rates to create a mass in the bone. The term “tumor” does not indicate whether an abnormal growth is malignant (cancerous) or benign, as both benign and malignant lesions can form tumors in the bone.
What is the signal intensity of hypointense synovial lesions?
Signal intensity is a feature of paramount importance in the MRI assessment of these synovial lesions. For T2-weighted images, fat is the tissue usually used for comparison [ 1 ]; thus, hypointense lesions have a lower signal compared with adjacent fat tissue on conventional spin-echo T2-weighted images.
Are there any hypointense lesions on a T2 MRI?
Hypointense lesions on T2-weighted images (both fat-suppressed and non-fat-suppressed) are less common and can sometimes be overlooked.
What causes T2 black lesions on knee MRI?
T2 black lesions on routine knee MRI: differential considerations. The majority of abnormal findings or lesions on T2-weighted fast spin-echo (FSE) magnetic resonance imaging (MRI) are hyperintense due to increased perfusion or fluid content, such as infections, tumours or synovitis.
How to diagnose osteochondral lesions of the knee?
■ Contrast and compare common entities that manifest as osteochondral lesions of the knee: acute traumatic osteochondral injuries, AVN, SIF of the knee, OCD, bone marrow edema-like lesions, and subchondral cystlike lesions in osteoarthritis. ■ Evaluate MRI findings of each condition and how they pertain to treatment.