Items tagged “cases”
5,552 results
Article
Lead poisoning
Lead poisoning or plumbism refers to the multi-organ toxicity exerted by exposure to lead. Manifestations differ based on a myriad of features including chronicity, exposure intensity, and age. Neurologic toxicity and hematologic toxicity are common features. Clinical manifestations vary, rangin...
Article
Lemon sign
The lemon sign, noted on antenatal imaging, is one of the many notable fruit-inspired signs. It is a feature when there appears to be an indentation of the frontal bone (depicting that of a lemon). It is classically seen as a sign of a Chiari II malformation and also seen in the majority (90-98%...
Article
Lesser petrosal nerve
The lesser petrosal nerve carries preganglionic parasympathetic fibers to the parotid gland. It is considered a branch of the glossopharyngeal nerve although it receives contributions from two further sources 3:
tympanic plexus: glossopharyngeal nerve via Jacobson's nerve (main contribution)
n...
Article
Linguine sign (breast)
Linguine sign, also known as the wavy line sign, is one of the imaging signs of intracapsular rupture of a breast implant 4.
Pathology
After implantation of a silicone or saline breast implant, a fibrous capsule (scar) forms around the implant shell. In an intracapsular rupture, the contents o...
Article
Lithopedion
Lithopedions, also known as stone babies, are a rare phenomenon which occurs most commonly when a fetus dies during an ectopic pregnancy.
Epidemiology
The estimated incidence is at ~1.5 to 1.8% of abdominal ectopic pregnancies 4.
Pathology
If the deceased fetus is too large to be re-absorbed...
Article
Low endplate signal on T1
Several conditions may give vertebral endplate T1 low signal on MRI. They include:
ankylosing spondylitis
vertebral metastases
disc infection
haemodialysis
Article
Lymphocytic hypophysitis
Lymphocytic hypophysitis is an uncommon non-neoplastic inflammatory condition that affects the pituitary gland. It is closely related to other inflammatory conditions in the region, namely orbital pseudotumor and Tolosa-Hunt syndrome.
Epidemiology
Lymphocytic hypophysitis is seen most frequent...
Article
Hereditary non-polyposis colorectal cancer
Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is an autosomal dominant condition which predisposes to a host of malignancies, including colorectal cancer. It is considered the most frequent form of hereditary colorectal cancer. Diagnosis requires evaluation us...
Article
Multiple endocrine neoplasia type 1
Multiple endocrine neoplasia type 1 (MEN1), also known as Wermer syndrome, is an autosomal dominant genetic disease that results in proliferative lesions in multiple endocrine organs, particularly the pituitary gland, pancreas, and parathyroid glands.
There are other multiple endocrine neoplas...
Article
Multiple endocrine neoplasia type IIb
Multiple endocrine neoplasia (MEN) type IIb, also known as MEN type 3 (MEN3) 3 or mucosal neuroma syndrome 2, accounts for only 5% cases of MEN2 and is characterized by:
pheochromocytoma(s): in 50% of patients, often bilateral, and can be extra-adrenal
medullary thyroid cancer: 100% of patient...
Article
Malignant vascular tumors
Malignant vascular tumors are rare, accounting for <1% of all sarcomas.
Pathology
intermediate grade
hemangioendothelioma
Kaposi sarcoma
high grade
hemangiopericytoma
angiosarcoma
Article
Malleus
The malleus (plural: mallei) is the most lateral middle ear ossicle, located between the tympanic membrane and the incus.
Gross anatomy
The malleus has a head, neck, and three distinct processes (manubrium (handle), anterior and lateral processes).
The head is oval in shape, and articulates p...
Article
Mastitis
Mastitis (rare plural: mastitides) refers to inflammation of the breast parenchyma, of which there are a number of subtypes:
acute mastitis
puerperal mastitis: occurs usually from infection with Staphylococcus spp. during lactation
non-puerperal mastitis: not related to lactation, and occurs ...
Article
Mean sac diameter
Mean sac diameter (MSD) is a sonographic measurement of the gestational sac, which is usually first seen at around 3 weeks after conception (5 weeks after the last menstrual period), when it measures 2-3 mm.
Measurement
MSD = (length + height + width)/3
Normal MSD (in mm) + 30 = days of pregn...
Article
Megalencephaly
Megalencephaly is a disorder characterized by an abnormally large brain. It is primarily a proliferative disorder of embryonic origin. It may involve all or part of the cerebral hemispheres and can be bilateral or unilateral. It is often associated with polymicrogyria or agyria.
Terminology
...
Article
Middle ear effusion
Middle ear effusions are frequent in children due to prominent adenoids and horizontal Eustachian tubes. These do not require imaging and can be treated expectantly / medically / surgically with tympanostomy tubes. Eustachian tube dysfunction is the accepted etiology, with resorption of air and ...
Article
Middle ear granulation tissue
Development of granulation tissue in the middle ear cavity is a generalized response to injury/inflammation, chronic otomastoiditis. It can either be typical or go down the pathway of becoming a cholesterol granuloma.
Radiographic features
Typical granulation tissue is common, more so than cho...
Article
Middle ear tumors
There are a range of middle ear tumors, which are more likely to be benign than malignant.
Pathology
The three most common middle ear tumors are (not in any particular order as there are differences in the literature) 1-3:
tympanic paraganglioma
congenital cholesteatoma
middle ear schwann...
Article
Middle lobe bronchiectasis
Middle lobe bronchiectasis is an imaging an imaging descriptor when bronchiectasis is confined to the middle lobe. When it (predominantly) involves the middle lobe it is sometimes is termed right middle lobe predominant (RMLP) bronchiectasis 2.
Middle lobe bronchiectasis may be seen in:
non-tu...
Article
Miscarriage
A miscarriage is the spontaneous termination of a pregnancy before 20 weeks of gestation. Fetal death after week 20 is termed fetal death in utero (FDIU).
Terminology
The term miscarriage is preferred by many over 'abortion' due to the use of the latter for therapeutic pregnancy termination, a...