Articles

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More than 200 results
Article

Renal artery aneurysm

Renal artery aneurysms (RAA) are the second most common visceral aneurysms (15-22%), the most common being splenic artery aneurysms (60%).  Epidemiology Renal artery aneurysms occur in ~0.1% of the population 6,8,10. They are more common in females 6. The median age at diagnosis is 50 years 8....
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Superior labral anterior posterior tear

Superior labral anterior posterior (SLAP) tears are injuries of the glenoid labrum, and can often be confused with a sublabral sulcus on MRI. Diagnosis The gold standard for diagnosis is made via diagnostic shoulder arthroscopy 9. Pathology SLAP tears involve the superior glenoid labrum, whe...
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Orthoroentgenogram

Orthoroentgenogram is a radiographic study used to evaluate anatomic leg length and calculate leg-length discrepancies. This study utilizes a long ruler placed on the film, and three radiographs including bilateral hips, knees and ankles. Similar studies used to evaluate true leg length include...
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Synovial enhancement

Synovial enhancement is an imaging feature typically observed on MRI imaging. It can occur in various forms and can be focal or diffuse. Pathology inflammatory synovitis transient synovitis of the hip infective synovitis inflammatory arthritides septic arthritis tuberculous septic arthri...
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Adult cystic renal disease

Adult cystic renal disease comprises multiple distinct hereditary and non-hereditary disease processes.  Pathology Etiology Hereditary adult polycystic kidney disease (APCKD), a.k.a. autosomal dominant polycystic kidney disease (ADPCKD) medullary cystic kidney disease von Hippel-Lindau dis...
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Canal wall down mastoidectomy

A canal-wall-down mastoidectomy comprises a group of mastoidectomies which is more open and extensive than a canal-wall-up mastoidectomy. In addition to traditional forms, various modified forms are now performed (see modified canal wall down mastoidectomy). They initially comprise the similar ...
Article

Jod-Basedow phenomenon

Jod-Basedow phenomenon is hyperthyroidism following iodine intake in a person with long term underlying thyroid disease. Pathology Jod-Basedow phenomenon occurs due to either overactivation of the entire thyroid gland or, more commonly, autonomous nodules within the gland after iodine repletio...
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Meyers and McKeever classification of ACL avulsion fractures

Meyers and McKeever classification is used to categorize ACL avulsion fractures. Usage The Meyers and McKeever classification is the most frequently used system (c. 2024) to describe ACL avulsion fractures 2. Classification Under the Meyers and McKeever system (with modifications by Zariczny...
Article

Periportal halo (CT/US)

Periportal halo or periportal collar sign refers to a zone of low attenuation seen around the intrahepatic portal veins on contrast-enhanced CT or hypoechogenicity on liver ultrasound. It likely represents periportal edema, which is often used as a synonymous term. Periportal haloes may occur ar...
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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...
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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.
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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...
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Right lower lobe collapse

Right lower lobe (RLL) collapse forms a triangular opacity extending from the hilum to the diaphragm. There is less overlap with the heart shadow compared to left lower lobe collapse.  Findings of lower lobe collapse can be grouped together as they are almost identical on both sides. For a gen...
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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...
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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...
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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

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) ...
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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...
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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...
Article

Hepatic lymphoma

Hepatic lymphoma is a term given to any form of hepatic involvement with lymphoma. This can be broadly divided into: secondary hepatic involvement with lymphoma: most common by far, many tend to be non-Hodgkin lymphoma (NHL) 1 primary hepatic lymphoma: extremely rare Pathology Risk factors f...
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