Items tagged “refs”

2,938 results found
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Codman triangle periosteal reaction

A Codman triangle is a type of periosteal reaction seen with aggressive bone lesions. The periosteum does not have time to ossify with shells of new bone (e.g. as seen in a single layer and multilayered periosteal reaction) in aggressive lesions, so only the edge of the raised periosteum will os...
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Colonic stricture

Colonic strictures can be long (>10 cm) or short. Short scirrhous colorectal carcinoma (apple core sign) post surgical (anastamotic stricture) Long malignancy scirrhous colorectal carcinoma gastrointestinal lymphoma inflammatory bowel disease ulcerative colitis Crohn disease post radi...
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Congenital cholesteatoma

Congenital cholesteatomas are identical to epidermoid cysts, differing only in name and location.  Pathology They are intraosseous inclusions of ectoderm and are therefore comprised of keratin debris and cholesterol. Characteristically, they are located at the petrous apex. In contrast, middle...
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Congenital facial palsy

A congenital facial palsy is an uncommon cause of neonatal asymmetric crying facies, which are more frequently due to absence or hypoplasia of the depressor anguli oris muscle, often associated with other congenital anomalies.  Epidemiology Congenital facial palsy is reported with an incidence...
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Conoid tubercle

The conoid tubercle also known as the coracoid tuberosity (not to be confused with the coracoid process of the scapula) is a bony prominence on the inferior surface of the lateral third of the clavicle.  It marks the insertion of the conoid ligament (which along with the trapezoid ligament) for...
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Corkscrew sign (midgut volvulus)

The corkscrew sign describes the spiral appearance of the distal duodenum and proximal jejunum seen in midgut volvulus 1. In patients with malrotation and volvulus, the distal duodenum and proximal jejunum do not cross the midline and instead pass in an inferior direction. These loops twist on ...
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Cotton wool appearance (bone)

The cotton wool appearance is a plain film sign of Paget disease and results from thickened, disorganized trabeculae which lead to areas of sclerosis in a previously lucent area of bone, typically the skull. These sclerotic patches are poorly defined and fluffy. See also Other Paget disease re...
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Cowdry bodies

Cowdry bodies are eosinophilic or basophilic neuronal intranuclear inclusions composed of nucleic acid and protein, this cytopathic changes are considered a hallmark of viral infection.1. Pathology Cowdry bodies are in fact fixation artifacts and not directly the result of the intracellular vi...
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Cranial nerves

The cranial nerves (TA: nervi craniales) are the twelve paired sets of nerves that arise from the cerebrum or brainstem and leave the central nervous system through cranial foramina rather than through the spine. The cranial nerves are numbered one to twelve, always using Roman numerals, i.e. I ...
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Multiple cystic neck lesions (differential)

The differential diagnosis for multiple cystic neck lesions is different to that for a solitary cystic neck mass. Differential diagnosis Cystic neck lesions are seen in: metastatic squamous cell carcinoma: older patient, M>F metastatic papillary thyroid carcinoma: usually a younger patient, ...
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Cystic parotid lesions

The differential for cystic parotid lesions includes: bilateral cystic parotid lesions Warthin tumor benign lymphoepithelial lesions of HIV Sjögren syndrome sialoceles dysgenetic polycystic disease of salivary glands unilateral cystic parotid lesion(s) Warthin tumor sialocele first bra...
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Cystic renal diseases

Cystic renal disease can be confusing. There are many conditions, many of which have similar names or are eponymous, and with a few exceptions, are relatively rare. It is easiest to think of them into two separate demographic: pediatric cystic renal diseases adult cystic renal disease
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Denervation changes in muscles

Denervation changes in muscles or denervation myopathy can be observed in a number of settings and results from partial or complete loss of innervation. There is a wide spectrum of clinical manifestations: temporary or permanent symptomatic or asymptomatic. Pathology Causes include 2: neur...
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Azygo-esophageal recess deviation

The azygoesophageal recess (AER) is formed by the interface between the right lung and the mediastinal reflection of the azygos vein and oesphagus. The line has a variable appearance: in its upper third, it deviates to the right, where it may either be straight or concave relative to the right ...
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Disorganized periosteal reaction

Disorganized or complex periosteal reaction has spicules with random orientation and appearance. It is often seen in highly aggressive processes. Pathology It has been associated with: osteosarcoma metastasis osteomyelitis chondrosarcoma Ewing sarcoma stress fracture malignant fibrous h...
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Arterial dissection

Arterial dissection occurs when blood enters the media through a tear or ulcer in the intima and tracks along the media, forming a second blood-filled channel within the wall. The normal lumen lined by intima is called the true lumen and the blood-filled channel in the media is called the false ...
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Dorello canal

Dorello canal channels the abducens nerve (CN VI) from the pontine cistern to the cavernous sinus.  Gross anatomy Dorello canal is found at the medial most end of the petrous ridge at the confluence of the inferior petrosal, basal, and cavernous sinuses. Boundaries superiorly: petrosphenoida...
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Dural sinus occlusive disease

Dural sinus occlusive disease (DSOD) is an infective form of dural sinus thrombosis (thrombophlebitis) commonly seen in the setting of acute otomastoiditis. It typically presents with: severe headaches high fevers sixth nerve palsy - due to involvement of Dorello's canal altered conscious st...
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Elbow ossification

Elbow ossification occurs at the six elbow ossification centers in a reproducible order. Being familiar with the order of ossification of the elbow is important in not mistaking an epicondylar fracture for a normal ossification center.  Appearance Order The order of appearances of the elbow o...
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Elevated hemidiaphragm

An elevated hemidiaphragm may result from direct and indirect causes which include: above the diaphragm 1 decreased lung volume atelectasis/collapse prior lobectomy or pneumonectomy pulmonary hypoplasia diaphragm 3-7 phrenic nerve palsy diaphragmatic eventration contralateral stroke: ...