Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.
735 results found
Article
Medical devices in the thorax
Medical devices in the thorax are regularly observed by radiologists when reviewing radiographs and CT scans.
Extrathoracic devices
tubing, clamps, syringes, scissors, lying on or under the patient
rubber sheets, foam mattresses, clothing, hair braids, nipple piercings, etc., may also b...
Article
Dilated ducts on breast imaging (differential)
Dilated ducts on breast imaging may be seen on many breast imaging modalities and can arise from a number of causes which can be both benign or malignant.
physiological lactational changes
mammary duct ectasia
breast neoplasm 2-3
Article
Well-defined breast cancers (differential)
Certain well-defined breast cancers tend to lack the characteristic spiculation and can give false reassurance of more benign entities on both ultrasound and mammography. These include:
certain high grade invasive ductal carcinomas: not enough time for a desmoplastic reaction to form spiculatio...
Article
Hyperechoic breast lesions
There are a number of lesions that appear hyperechoic on ultrasound. Such lesions can be either completely or partly hyperechoic and include both benign and malignant entities.
Benign
fat containing breast lesions
lipoma of the breast
fibroadenolipoma (hamartoma) of the breast
fo...
Article
Cystic breast mass
A cystic breast mass is a mass that contains both solid and fluid components. This can occur from both benign and malignant causes.
Benign
complex breast hematoma
complex breast abscess
breast cyst with associated inflammation and hemorrhage
galactocoele
fibrocystic changes and oil cysts 2...
Article
Fetal rib fractures
Fetal rib fractures can be caused by certain skeletal dysplasias. These include:
osteogenesis imperfecta: type II - one of the classical causes of fetal rib fractures
achondrogenesis: type Ia - Houston-Harris sub type
Article
Fetal limb bowing
Fetal limb bowing may be a feature of skeletal dysplasia, particularly if it is severe. A mild degree of lateral bowing of the femur can occur as part of normal variation.
Conditions associated with fetal limb bowing include:
campomelic dysplasia 1
thanatophoric dysplasia 2: particularly type...
Article
Calcific axillary lymphadenopathy (differential)
Calcific axillary lymphadenopathy is in general, more concerning than axillary lymphadenopathy alone and is particularly so if it contains microcalcifications. While this is concerning for malignancy, it can also occur from occasional nonmalignant causes.
Pathology
Etiology
metastatic axillar...
Article
Unilateral axillary lymphadenopathy (differential)
Unilateral axillary lymphadenopathy while being more concerning than bilateral axillary lymphadenopathy can still arise from a variety of benign, as well as malignant, causes.
Benign
mastitis
other regional infective causes
tuberculosis
ipsilateral arm infection, e.g. cellulitis
silicone i...
Article
Skin thickening on mammography (differential)
The presence of skin thickening on mammography is variably defined, usually being more than 2 mm in thickness. It can result from a number of both benign and malignant causes. They include:
Malignant
inflammatory breast cancer: one of the most concerning causes of skin thickening: this usually...
Article
Asymmetry (mammography)
Asymmetries in mammography represent a spectrum of morphological descriptors for a unilateral fibroglandular-density finding seen on one or more mammographic projections that do not meet criteria for a mass. The term refers to a density finding and should not be confused with asymmetry in breast...
Article
High risk breast lesion
The term high-risk breast lesion is given to a breast lesion that carries an increased risk for the future development of breast cancer or carries suspicion of a more sinister pathology around or in association with the lesion. The term has some overlap with borderline breast disease. Many radio...
Article
Coarse macrocalcifications within the breast
Coarse macrocalcifications within the breast are a morphological descriptive term for a type of breast calcification.
Epidemiology
Associations
involuting fibroadenomas (classic popcorn calcification)
chronic renal disease with hypercalcemia 1
rarely seen in malignancy 2
invasive breast c...
Article
Milk of calcium within a breast cyst
Milk of calcium within a breast cyst is a mammographic feature observed when there is dependent calcium layering within breast cysts. It is typically observed as "tea cup" or "crescent shaped" calcifications on a true lateral (LM or ML) view or occasionally on a MLO view. On a CC view, these cal...
Article
Bone-forming tumors
Bone-forming tumors are a subset of bone tumors that are characterized by their propensity to form excess osteoid. They can be further subdivided into benign and malignant tumors.
Benign tumors
osteoid osteoma
osteoblastoma
bone island
osteopoikilosis
osteoma
ossifying fibroma 1
Malignan...
Article
Demyelinating disorders
Demyelinating disorders are a subgroup of white matter disorders characterized by the destruction or damage of normally myelinated structures. These disorders may be inflammatory, infective, ischemic or toxic in origin and include 1-7:
autoimmune demyelination
multiple sclerosis (MS)
Marburg ...
Article
Hypomyelinating disorders
Hypomyelinating disorders are a heterogeneous subset of white matter disorders characterized by abnormally low amounts of myelination.
In distinction to other myelin disorders, hypomyelination is a permanent deficiency in myelin deposition rather than myelin destruction (i.e. demyelination) or ...
Article
Amorphous calcifications (breast)
Amorphous calcifications, previously known as indistinct calcifications, are a morphological descriptor for breast calcifications that are small and/or hazy such that no clearly defined shape/form can be ascribed.
Pathology
Many benign and malignant conditions may be seen in association with ...
Article
Transalar herniation
Transalar (transsphenoidal) herniation describes herniation of brain matter in and around the middle cranial fossa across the greater sphenoid wing and can be ascending or descending. Compression of structures against the sphenoid bone results in symptoms.
Pathology
Transalar herniation is not...
Article
Fetal cardiac tumors
Fetal cardiac tumors refer to primary cardiac tumors that can present in the in utero population.
Epidemiology
Fetal cardiac tumors are rare; the prevalence, reported from autopsy studies of patients of all ages, varies from 0.0017-0.28 % 2.
Pathology
Known cardiac tumor types that present ...
Article
Frontal bossing
Frontal bossing is a calvarial radiographic feature where the front of the skull appears protruding anteriorly. It is best appreciated on a sagittal or lateral image.
Pathology
This feature can be seen in many conditions (in alphabetical order):
18q syndrome
acromegaly
achondroplasia
ß-tha...
Article
Absent fetal stomach on ultrasound (differential)
Non-visualization of the fetal stomach on ultrasound can occur with various physiological as well as pathological processes. It becomes a significant sonographic observation >14 weeks of gestation (about the time the fetus begins to swallow).
Causes include:
physiological emptying: transient
...
Article
Fetal intracranial hemorrhage
Fetal intracranial hemorrhage may occur either within the cerebral ventricles, subdural space or infratentorial fossa.
Pathology
Hemorrhages can occur in a number of situations:
mechanical trauma, e.g. maternal abdominal blunt or birth trauma
severe fetal hypoxia
background fetal thrombocyt...
Article
Fetal brain tumors
Fetal brain tumors are uncommon and tends to have very different pathological spectrum than that observed in adults; in order of decreasing frequency:
fetal intracranial teratoma: most common tumor by far
astrocytoma/glioblastoma: next most common
adamantinomatous craniopharyngioma
primitive...
Article
Fetal intracranial calcification
Fetal intracranial calcification refers to intracranial calcification detected in utero. This can arise from a number of pathologies which include:
in utero infections
fetal toxoplasmosis infection: calcification tends to be randomly distributed
fetal cytomegalovirus infection1: calcificatio...
Article
Pneumatocele
Pneumatoceles are intrapulmonary gas-filled cystic spaces that can have a variety of sizes and appearances. They may contain gas-fluid levels and are usually the result of ventilator-induced lung injury in neonates or post-infectious. They should not be mistaken for a cavitating lung mass.
Epi...
Article
Pulmonary bleb
Pulmonary blebs are small subpleural thin-walled air-containing spaces, not larger than 1 or 2 cm in diameter (with the precise limit varying by source). Their walls are less than 1 mm thick. If they rupture, they allow air to escape into the pleural space resulting in a spontaneous pneumothorax...
Article
Uterine enlargement (differential)
Uterine enlargement can occur in a number of situations from both diffuse and focal processes. These include:
gestation related events
normal intrauterine pregnancy
molar pregnancy - gestational trophoblastic disease
postpartum uterus - still larger than usual
hormonal ...
Article
Right lower lobe collapse
Right lower lobe (RLL) collapse has distinctive features, and is usually relatively easily identified. The smaller overlying heart shadow obscures less lung compared with left lower lobe collapse.
Findings of lower lobe collapse can be grouped together as they are almost identical on both side...
Article
Right upper lobe collapse
Right upper lobe collapse has distinctive features, and is usually easily identified on frontal chest radiographs; much more so than left upper lobe collapse.
For a general discussion please refer to the article on lobar collapse.
Radiographic features
Chest radiograph
Collapse of the right ...
Article
Right middle lobe collapse
Right middle lobe collapse (or simply termed middle lobe collapse) has distinctive features, but can be subtle on frontal chest radiographs.
For a general discussion please refer to the article on lobar collapse.
It is important to note that of all the lobes, the right middle lobe is the mo...
Article
Grouped calcifications
The term grouped calcifications is used in mammography when relatively few breast microcalcifications reside within a small area. There must be at least five calcifications present within 1 cm of each other 3. At the most, it may refer to a larger number of calcifications present within 2 cm of ...
Article
Multicentric breast cancer
A multicentric breast cancer is a term given to a breast cancer where there are two or more breast cancers separated by normal breast tissue (often taken as 5 cm of separation 4). It is related to but distinct from the term multifocal breast cancer.
At a pathological level It can also mean 2
t...
Article
Enlargement of the cardiac silhouette
Enlargement of the cardiac silhouette on a frontal (or PA) chest x-ray can be due to a number of causes 1:
cardiomegaly (most common cause by far)
pericardial effusion
anterior mediastinal mass
prominent epicardial fat pad
expiratory radiograph
AP projection (e.g supine radiographs taken w...
Article
Papillary lesions of the breast
Papillary lesions of the breast comprise a wide group and range from benign to malignant.
Pathology
They develop as tufts of epithelium with a fibrovascular core that arborizes into branching papillae and protrude into the duct lumen.
Benign
papilloma of breast / intraductal papilloma of the ...
Article
Small placenta
A small placenta if observed on antenatal ultrasound can arise from a number of situations. They include:
variation in placental morphology: where only part of the placenta is seen
bilobed placenta: with only one lobe seen
succenturiate lobe: with either main lobe or succenturiate lobe not se...
Article
Multifocal breast cancer
Multifocal breast cancer refers to two or more individual breast cancers diagnosed at the same time within the same quadrant of the same breast 1.
Article
Soft tissue calcification
Soft tissue calcification is commonly seen and caused by a wide range of pathology.
Differential diagnosis
There is a wide range of causes of soft tissue calcification 1:
dystrophic soft tissue calcification (most common)
chronic venous insufficiency 2
vascular
arterial c...
Article
Fetal bowel dilatation
Fetal bowel dilatation can occur from many causes, which include:
intestinal atresias: mainly distal
anal atresia
apple-peel intestinal atresia
ileal atresia
jejunal atresia
jejuno-ileal atresia
Hirschsprung disease
megacystis microcolon hyperperistalsis syndrome 4
congenital chloride d...
Article
Asymmetry in breast size
Asymmetry in breast size can arise from a number of factors.
Pathology
Breasts are rarely absolutely the same size or volume. Normal variation is common. Most females have slight discrepancies in breast size. Asymmetric progressive breast enlargement is unusual but known. The role of the breas...
Article
Abnormally thickened endometrium (differential)
Abnormally thickened endometrium on imaging may occur for a number of reasons which may be categorized based on whether or not they are related to pregnancy. Etiologies may also be classified based on whether the patient is premenopausal or postmenopausal.
Differential diagnosis
Pregnancy-rela...
Article
Vertebral body mass
The differential diagnosis for a vertebral body mass is broad and may range from a completely benign bone island to a malignant primary bone tumor.
Classification
Broadly, these lesions can be separated into:
non-neoplastic lesions
primary bone tumors
secondary metastatic disease
Non-neopl...
Article
Fetal intracranial cystic lesions
Fetal intracranial cystic lesions can arise from a number of pathologies, including:
Non-tumourous
fetal arachnoid cyst
fetal choroid plexus cyst
fetal connatal cyst
fetal porencephalic cyst
fetal interhemispheric cyst
fetal subependymal cyst
dorsal cyst of holoprosencephaly
Blake pouc...
Article
Lethal skeletal dysplasias
Lethal skeletal dysplasias form a heterogeneous group that is commonly characterized as being non-survivable for prolonged periods ex-utero. They include (in alphabetical order):
achondrogenesis
atelosteogenesis
campomelic dysplasia
chondrodysplasia punctata: lethal variants
...
Article
Carotid pacemaker
Carotid pacemakers, also known as implantable carotid sinus stimulators, are devices that deliver activation energy, via carotid leads, to the carotid baroreceptors. This is sometimes offered for drug-resistant hypertension. The baroreceptors send signals to the brain and the signals are interpr...
Article
Congenital renal anomalies
Congenital renal anomalies comprise of vast spectrum of pathologies and include:
renal agenesis
renal dysgenesis
congenital renal hypoplasia
congenital megacalyectasis
congenital cystic renal disease
infantile polycystic renal disease: autosomal recessive polycystic ki...
Article
Altered breast density between two mammograms
Mammographic screening detects early breast cancers and thereby reduces potential mortality. However, its sensitivity is inversely related to breast density 1.
Altered density between two mammograms can arise in a number of situations:
Affecting both breasts:
interval commencement/cessation ...
Article
Fetal intra-abdominal cysts (differential)
Fetal intra-abdominal cystic lesions can arise from a number of physiological and pathological causes.
Physiological
fetal gastric dilatation / fetal gastric bubble (can be pathological if there is a gastric outlet obstruction
normal fetal gallbladder
Pathological
No color flow
fetal chole...
Article
Winking owl sign (spine)
The (absent) pedicle sign, also called the winking owl sign, occurs on plain radiograph of the spine when a pedicle is absent 5.
The term, winking owl sign, where the missing pedicle corresponds to the closed eye, the contralateral pedicle to the other round open eye, and the spinous process to...
Article
Narrow fetal thorax
A narrow fetal thorax on antenatal ultrasound can be present with a number of anomalies which include:
achondrogenesis
campomelic dysplasia
homozygous achondroplasia
Jarcho-Levin syndrome
Jeune syndrome - asphyxiating thoracic dysplasia
Russell-Silver dwarfism
short rib polydactyly syndro...
Article
Calcified pulmonary nodules
Calcified pulmonary nodules are a subset of hyperdense pulmonary nodules and a group of nodules with a relatively narrow differential.
Pathology
Etiology
The most common cause of nodule calcification is granuloma formation, usually in the response to healed infection.
healed infection
cal...
Article
Pulmonary mass
A pulmonary mass is any area of pulmonary opacification that measures more than 30 mm, an arbitrary but useful measurement. The commonest cause of a pulmonary mass is primary lung cancer 1-3:
bronchogenic carcinoma
granuloma: most common non-malignant cause
sarcoidosis
infections
Mycobacter...
Article
Interstitial lung disease
Interstitial lung disease (ILD) is an umbrella term that encompasses a large number of disorders that are characterized by diffuse cellular infiltrates in a periacinar location. The spectrum of conditions included is broad, ranging from occasional self-limited inflammatory processes to severe de...
Article
Low signal intensity renal parenchyma
There are relatively few causes of low signal intensity renal parenchyma. Causes include:
hemolysis
paroxysmal nocturnal hemoglobinuria
mechanical: malfunctioning prosthetic cardiac valve
sickle cell disease
infection
hemorrhagic fever with renal syndrome (HFRS)
vascular disease
acute re...
Article
Cystic mass adjacent to the angle of mandible (differential)
The differential diagnosis of a cystic mass adjacent to the angle of mandible includes:
2nd branchial cleft cyst
lymphatic malformation (lymphangioma)
cystic lymphadenopathy
from tuberculosis
from metastatic squamous cell carcinoma
from metastatic papillary thyroid cancer
See also
cys...
Article
Breast calcifications
Breast calcifications are deposits of calcium salts in the breast, which are radio-opaque on mammography. The majority are benign, but they can be associated with cancer. The ability to diagnose and appropriately manage the significant microcalcifications and differentiate them from innocuous fi...
Article
Fetal anterior abdominal wall defects
Fetal anterior abdominal wall defects can occur with a number of pathologies.
Individual entities
omphalocele
gastroschisis
cloacal exstrophy
bladder exstrophy
Syndromes/complexes
limb body wall complex
OEIS complex
omphalocele-radial ray (ORR) complex
Pentalogy of Cantrell
amniotic ...
Article
Echogenic fetal lung lesions
Echogenic fetal lung lesions on antenatal ultrasound can be detected in a number of situations. They include:
Airway obstructions: lung are often enlarged and echogenic bilaterally
congenital high airways obstruction syndrome (CHAOS)
tracheal atresia
congenital tracheal stenosis
laryngeal a...
Article
Spinal cord compression
Spinal cord compression (SCC) is a surgical emergency, usually requiring prompt surgical decompression to prevent permanent neurological impairment. If the spinal roots below the conus medullaris are involved, and there are characteristic symptoms and signs, it is termed cauda equina syndrome.
...
Article
Shortened fetal humerus
A shortened fetal humerus is a morphological description and is usually defined when the humeral length falls below the 5th percentile or less than 0.9 as predicted by the biparietal diameter (BPD). It can occur in isolation or in association with a number of other anomalies.
The humeral length...
Article
Spinal metastases
Spinal metastasis is a vague term which can be variably taken to refer to metastatic disease to any of the following:
vertebral metastases (94%)
may have epidural extension
intradural extramedullary metastases (5%)
intramedullary metastases (1%)
Each of these are discussed separately. Below...
Article
Syndactyly
Syndactyly (plural: syndactylies) refers to a congenital fusion of two or more digits. It may be confined to soft tissue (soft tissue syndactyly / simple syndactyly) or may involve bone (bony syndactyly / complex syndactyly).
Epidemiology
The overall estimated incidence is at ~1 per 2500 to 50...
Article
Cutaneous calcifications in breast imaging
Cutaneous calcifications in breast imaging can form in dermal sweat glands after low grade folliculitis and inspissation of sebaceous material. Calcifications may also form in moles and other skin lesions. The vast majority of calcifications are coincidental findings on mammography.
Radiographi...
Article
Placentomegaly
Placentomegaly is a term applied to an abnormally-enlarged placenta.
Epidemiology
Associations
It can be associated with a number of maternal and fetal disorders which include:
maternal
maternal anemia(s)
maternal diabetes
chronic intrauterine infections
alpha-thalassemia
fetal
umbilic...
Article
Coup-contrecoup injury (brain)
A coup-contrecoup injury is a term applied to head injuries and most often cerebral contusions and traumatic subarachnoid hemorrhage. It refers to the common pattern of injury whereby damage is located both at the site of impact (often less marked) and on the opposite side of the head to the poi...
Article
Shortened fetal femur
A shortened fetal femur is a morphological descriptor and is usually defined when the femoral length falls below the 5th centile for gestational age (some define it when it is under the 2.5th centile 5) or less than 0.91 predicted by the biparietal diameter (BPD). It can occur in isolated or in ...
Article
Fetal pleural effusion
Fetal pleural effusions (FPE) refer to an accumulation of pleural fluid in utero. It can refer to either a fetal chylothorax or a fetal hydrothorax.
Pathology
A fetal pleural effusion can occur as part of hydrops fetalis, in association with other anomalies without hydrops or in isolation - pr...
Article
Fetal intrahepatic calcification
Fetal intrahepatic calcification can be a relatively common finding. Calcifications in the liver can be single or multiple and in most cases in which isolated hepatic calcific deposits are detected, there is usually no underlying abnormality.
The presence of isolated intrahepatic calcification ...
Article
Subarachnoid FLAIR hyperintensity
There are a wide range of causes for subarachnoid FLAIR hyperintensity, both pathological and artifactual.
Differential diagnosis
Pathological causes
subarachnoid hemorrhage
meningitis
leptomeningeal carcinomatosis
FLAIR vascular hyperintensities in acute stroke 1,4,8
moyamoya disease
m...
Article
Fetal ascites
Fetal ascites refers to the accumulation of free fluid in the fetal abdomen. It is often considered under the same spectrum of hydrops fetalis.
Pathology
Etiology
any condition that results in hydrops fetalis
additional causes include
idiopathic
bowel perforation (e.g. meconium peritonitis...
Article
Fat containing breast lesions
Fat containing breast lesions generally have some radiolucent component on mammography.
Pathology
They are generally classified at BIRADS II lesions.
Common
breast lipoma
breast hamartoma
fat necrosis within the breast/oil cyst
intramammary lymph node: classically has a cen...
Article
Differential diagnosis for PV bleeding in pregnancy
Per vaginal (PV) bleeding during pregnancy is a common clinical presentation that often necessitates obstetric ultrasound for the assessment of the hemorrhage, and of fetal well being.
The potential causes vary with the stage of gestation.
Bleeding in the first trimester
miscarriage
threaten...
Article
Hypotelorism
Hypotelorism refers to an abnormal decrease in distance between any two organs although some authors use the term synonymously with orbital hypotelorism meaning an abnormal decrease in the distance between the two eyes (the eyes appear too close together). The article mainly focuses on the latte...
Article
Umbilical cord cyst
Umbilical cord cysts can refer to any cystic lesion associated with the umbilical cord. They can be single (more common) or multiple.
Epidemiology
They may be seen in ~3% of pregnancies in the first trimester 8.
Associations
There are associations (especially when there are additional sonogr...
Article
Fetal clenched hands
Fetal clenched hands are an antenatal ultrasound observation where the fetal hands are in a constant (permanently) clenched position as if being unable to extend.
Epidemiology
Associations
Several syndromic conditions are associated with this observation including:
aneuploidic
Edwards syndr...
Article
Cystic retroperitoneal lesions
Cystic retroperitoneal lesions carry a relatively broad differential, which includes:
retroperitoneal lymphatic malformation
retroperitoneal mucinous cystadenoma
retroperitoneal cystic teratoma
retroperitoenal cystic mesothelioma
pseudomyxoma retroperitonei with cystic change
perianal muci...
Article
WHO classification of uterine tumors
The World Health Organization (WHO) classification of tumors of the uterine corpus is a commonly used classification system for uterine tumors. It is part of the 5th edition WHO classification of female genital tumors, published in 2020 1.
Classification
Endometrial epithelial tumors and prec...
Article
Basal ganglia and thalamus signal abnormalities
Basal ganglia and thalamus signal abnormalities occur in a wide variety of conditions. Ischemia/hypoxia, metabolic disorders and toxins, particularly those that affect the respiratory chain, have a predilection for affecting the basal ganglia as they are highly metabolically active.
They can b...
Article
Patella alta
Patella alta, or a high-riding patella, describes a situation where the position of the patella is considered high. It may be idiopathic or may result secondary to a patellar tendon rupture.
Epidemiology
Associations
Several conditions are known to be associated with patella alta, including:...
Article
Bilateral middle cerebellar peduncle lesions
Lesions of both middle cerebellar peduncles is uncommon, but has a relatively long list of differential diagnoses, including 1,2:
neurodegenerative diseases
multiple systemic atrophy (MSA)
olivopontocerebellar atrophy
Shy-Drager syndrome
spinocerebellar atrophy
fragile X-associated tremor/...
Article
Differential diagnosis for calcified masses in the mandible
Differential diagnosis for calcified masses in the mandible includes:
calcifying odontogenic cyst (Gorlin cyst)
calcifying epithelial odontogenic tumor (Pindborg tumor)
fibrous dysplasia
foreign body
odontoma
cemento-ossifying fibroma
osteoma
synovial osteochondromatosis
focal sclerosi...
Article
Right atrial enlargement
Right atrial (RA) enlargement is less common, and harder to delineate on chest radiograph, than left atrial (LA) enlargement.
Pathology
Etiology
Enlargement of the right atrium (RA) can result from a number of conditions, including:
raised right ventricular pressures
pulmonary arterial hype...
Article
Cavernous sinus mass
A cavernous sinus mass has a wide differential, including:
meningioma
orbital apical inflammation with cavernous sinus involvement (Tolosa-Hunt syndrome)
infection
schwannoma
any of the cranial nerves traversing the cavernous sinus: III, IV, V (V1 and V2) and VI
trigeminal schwannoma is...
Article
Polyostotic bone lesions in adults
Common causes of polyostotic bone lesions in adults include:
inflammatory
arthritic or synovial-based lesions
neoplastic
benign
non-ossifying fibromas (fibroxanthomas)
polyostotic fibrous dysplasia (McCune-Albright syndrome)
malignant
multiple myeloma
metastases
metabolic
primary hype...
Article
Obstructive uropathy
An obstructive uropathy is a catch-all term encompassing any cause of complete or partial, congenital or acquired, and permanent or intermittent obstruction of the urinary tract. Depending on the severity of obstruction and extent, it may result in permanent change in both the collecting system ...
Article
Coronal vertebral cleft
Coronal vertebral clefts refer to the presence of radiolucent vertical defects on a lateral radiograph.
Epidemiology
It is most often seen in premature male infants 1,3. As they can occur as part of normal variation (especially in the lower thoracic-upper lumbar spine of premature infants) t...
Article
Diffusely increased bone marrow FDG uptake
A diffuse homogeneous bone marrow FDG uptake usually reflects hyperplastic bone marrow which can be seen in the following conditions:
therapy-related
granulocyte colony-stimulating factor (G-CSF)
post-chemotherapy
erythropoietin
pathological process
myelodysplastic syndromes
beta-thalasse...
Article
Periportal hyperechogenicity
Periportal hyperechogenicity can result from many causes including:
pneumobilia
cholecystitis
schistosomiasis of the portal region
recurrent pyogenic cholangitis (oriental)
inflammatory bowel disease: has been described to give "echo-rich" periportal cuffing 2
Article
Periportal hypoechogenicity
Periportal hypoechogenicity can result from many causes:
orthotopic liver transplant rejection
congestive hepatopathy
malignant lymphatic obstruction
cholangitis
viral hepatitis
See also
periportal hyperechogenicity
periportal halo
Article
Breast density
Breast density refers to the amount of fibroglandular tissue in a breast relative to fat. It can significantly vary between individuals and within individuals over a lifetime.
Classification
There are four descriptors for breast density on mammography in the 5th edition of BI-RADS 1,2:
a...
Article
Retained gallstone
Retained gallstones, also called dropped or slipped gallstones, are common during a laparoscopic cholecystectomy, with a reported incidence of 0.1–20%, and occur when gallstones are inadvertently spilled into the peritoneal cavity.
Clinical presentation
Many cases of dropped gallstones will be...
Article
Cardiomegaly
Cardiomegaly is a catch-all term to refer to enlargement of the heart, and should not be confused with causes of enlargement of the cardiomediastinal outline, or enlargement of the cardiac silhouette.
Pathology
Etiology
There are many etiologies for cardiomegaly:
congestive heart failure...
Article
Intracranial cystic lesions in the perinatal period
Intracranial cystic lesions in the perinatal period can carry a relatively wide differential which includes:
Supratentorial cystic lesions
cysts
arachnoid cyst
choroid plexus cyst
connatal cyst
holoprosencephaly
multicystic encephalomalacia
periventricular leukomalacia
porencephalic cys...