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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.

16,879 results found
Article

Sphenomandibular ligament

The sphenomandibular ligament is one of the two extrinsic ligaments of the mandible, the other being the stylomandibular ligament. The sphenomandibular ligament descends from the spine of the sphenoid bone onto the medial surface of the mandibular ramus, attaching to the lingula. It is the prim...
Article

Craniopagus

Craniopagus twins are conjoined twins that are fused at any part of the skull, except the face, foramen magnum, skull base and the vertebral column. The fused structures are most often the cranium, meninges, and dural venous sinuses. Brains tend to be separate; however, they may be connected by...
Article

Rachipagus

Rachipagus twins are an extremely rare type of conjoined twins. They are joined in the dorsal aspect and face away from each other. Fusion of the occiput with varying segments of the vertebral column may occur, resulting in the sharing of the spinal cords. The fusion terminates above the sacrum...
Article

Misty mesentery sign

Misty mesentery sign is a sign on CT in which mesenteric fat with increased attenuation mimics mistiness. Just as with fat stranding elsewhere, a number of processes can lead to the appearance including infiltration by inflammatory cells, edema, lymphatic accumulation, hemorrhage, tumor infiltra...
Article

Choroid plexus

The choroid plexus is located within the cerebral ventricles and is made of choroidal epithelial cells (type of ependymal cell), loose connective tissue (tela choroidea), and permeable capillaries. It produces cerebrospinal fluid.  The choroid plexuses also form the blood-CSF barrier alongside ...
Article

Skeletal survey (overview)

The skeletal survey is a radiographic series performed to survey the entire skeleton (axial skeleton, upper and lower limbs) for pathology or injury. Specific projections vary depending on the clinical indication and the institution's protocol. There are various clinical indications that may wa...
Article

Bowl of grapes sign

The bowl of grapes sign has been described in synovial sarcoma. It refers to the characteristic multilobulated lesion subdivided by multiple septa, forming large cystic foci with regions of hemorrhage.
Article

Congenital facial nerve aplasia

Congenital facial nerve aplasia is a rare condition where the patient presents with signs of facial nerve paralysis. Clinical presentation Patients present with unilateral or bilateral facial weakness characterized by facial asymmetry, incomplete closure of eyelid, deviation of angle of mouth ...
Article

Psoriasis

Psoriasis is an inflammatory dermatological disease with several variants. The most common variant is plaque psoriasis, other variants of the disease are guttate, erythrodermic and pustular psoriasis 1. Epidemiology There is a geographic variation in the prevalence of psoriasis such that popul...
Article

Extradural neural axis compartment

Extradural neural axis compartment (EDNAC) exists from the tip of the coccyx all the way to the back of the globe, and yet it is relatively unknown as a concept. It is bounded externally by the periosteum of the vertebrae and sacrum inferiorly and the skull superiorly, and the visceral (meningea...
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

Pituitary stalk interruption syndrome

Pituitary stalk interruption syndrome, also known as pituitary stalk transection syndrome, is a syndrome characterized by an absent or hypoplastic anterior pituitary gland, thin or absent infundibulum, and ectopic posterior pituitary location. Epidemiology Pituitary stalk interruption syndrome...
Article

Os odontoideum

Os odontoideum (plural: ossa odontoidea) is an anatomic variant of the odontoid process of C2 and needs to be differentiated from persistent ossiculum terminale and from a type 2 odontoid fracture. It can be associated with atlantoaxial instability.  Although it was originally thought to be a c...
Article

Anderson and Montesano classification of occipital condyle fractures

The Anderson and Montesano classification is a widely used system for describing occipital condyle fractures. It divides injuries into three types based on morphology and mechanism of injury 1-5. Classification type I: impacted type occipital condyle fracture morphology: comminution of the co...
Article

Caput medusae sign (developmental venous anomaly)

The caput medusae sign also sometimes known as a palm tree sign refers to developmental venous anomalies of the brain, where a number of veins converge centrally into a single draining vein.  The sign is seen on both CT and MRI when contrast medium is administered. Angiographically the caput me...
Article

Shear wave elastography

Shear wave elastography is a developing variation of ultrasound imaging. The concept is similar to strain elastography, but instead of using transducer pressure to compare a shift in an ultrasound A-line (thereby measuring changes in strain), a higher intensity pulse is transmitted to produce s...
Article

Germ cell tumors of the ovary

Germ cell tumors of the ovary account for approximately 15-20% of all ovarian tumors. In children and adolescents, up to 60% of ovarian tumors can be of germ cell origin. They include: ovarian teratoma(s): commonest primary benign tumor of ovary and commonest germ cell tumor: mature (cystic) ...
Article

Aortic arch

The aortic arch represents the direct continuation of the ascending aorta and represents a key area for a review of normal variant anatomy and a wide range of pathological processes that range from congenital anomalies to traumatic injury. Summary origin: continuation of the ascending aorta at...
Article

Orthopantomography

The orthopantomogram (also known as an orthopantomograph, pantomogram, OPG or OPT) is a panoramic single image radiograph of the mandible, maxilla and teeth. It is often encountered in dental practice and occasionally in the emergency department; providing a convenient, inexpensive and rapid way...
Article

Flame sign (carotid)

The flame sign refers to a gradual tapering of contrast opacification in the mid-cervical internal carotid artery, sparing the carotid bulb. The sign can be observed on angiography (digital subtraction angiography 1, CT angiography 1, or contrast-enhanced MR angiography 2) in either of two scena...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.