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.

1,233 results found
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Obturator artery

The obturator artery is a branch of the anterior division of the internal iliac artery. It provides vascular supply within the pelvis and lower limb.  Summary origin: anterior division of the internal iliac artery location: pelvis and lower limb supply: pelvic muscles, ilium, head of femur, ...
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Obturator vein

The obturator vein travels between the adductor region of thigh and internal iliac vein entering the pelvis through the obturator foramen (along with the obturator artery and obturator nerve).  Course and termination Along the pelvic side wall the vein travels between the ureter and the intern...
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Occipital artery

The occipital artery, a posterior branch of the external carotid artery, opposite the external maxillary, near the lower margin of the posterior belly of the digastic muscle, and ends in the posterior part of the scalp. Summary origin: branch of the external carotid artery at the level of the ...
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Occipital sinus

The occipital sinus is one of the smallest dural venous sinuses and lies, as its name suggests, on the inner surface of the occipital bone. Tributaries from the marginal sinus of the foramen magnum, some of which connect with both the sigmoid sinus and vertebral venous plexus, coalesce to pass i...
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Esophageal hiatus

The esophageal hiatus is the opening in the diaphragm through which the esophagus passes from the thoracic to abdominal cavity. It is one of three apertures in the diaphragm and is located in the right crus. It is situated in the muscular part of the diaphragm at the level of T10 and is ellipti...
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Esophageal varix

Esophageal varices describe dilated submucosal veins of the esophagus, and are an important portosystemic collateral pathway. They are considered distinct from gastric varices, which are less common. Epidemiology Esophageal varices are present in ~50% of patients with portal hypertension 1,2. ...
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Onyx

OnyxTM is the trade name for a liquid embolic agent used in interventional radiology for the occlusion of blood vessels in embolization therapy. It is an elastic copolymer (ethylene vinyl alcohol copolymer (EVOH)), dissolved in dimethyl-sulfoxide (DMSO). Micronised tantalum powder is also added ...
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Ophthalmic artery

The ophthalmic artery is a branch of the C6 segment of the internal carotid artery (ICA). Gross anatomy Origin The ophthalmic artery arises medial to the anterior clinoid process as the ICA exits the cavernous sinus. It originates from the antero- or supero-medial surface of the ICA. Course ...
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Orbital venous varix

Orbital venous varix (OVV) is an uncommon vascular malformation that is composed of enlarged single or multiple tubular venous channels with direct communication to the systemic venous system.  Terminology Orbital venous varices are divided into primary and secondary. Primary orbital varices a...
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Orbitofrontal artery

The orbitofrontal arteries, or frontobasal arteries, supply the orbitofrontal cortex. They consist of both medial and lateral orbitofrontal arteries. Gross anatomy The medial orbitofrontal artery (MOFA) is most commonly the first branch of the A2 segment of the anterior cerebral artery. It ari...
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Ovarian artery

The ovarian artery is a paired structure and is the main gonadal artery in females. Gross anatomy Origin The ovarian artery arises anterolaterally from the aorta just inferior to the renal arteries and superior to the inferior mesenteric artery (between L2 and L3). Course Descends caudally ...
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Ovarian vein embolization

Ovarian vein embolization is an interventional technique primarily used towards the treatment of varicosities. Indications The main indications are: as part of management of pelvic congestion syndrome 1-4 to treat pelvic varicosities diagnosed by imaging to treat labial and/or perineal vari...
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Ovarian vein syndrome

Ovarian vein syndrome is a relatively rare condition where a dilated ovarian vein (ovarian venous varix) causes notching, dilatation, or obstruction of the ureter. This is usually secondary to varicosities of the ovarian vein or ovarian vein thrombosis and occurs at the point where the ovarian v...
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Ovarian vein thrombosis

Ovarian vein thrombosis (actually most often thrombophlebitis) occurs most commonly in postpartum patients and can result in pulmonary emboli. A presentation is usually with acute pelvic pain in the postpartum period, then termed puerperal ovarian vein thrombosis or postpartum ovarian vein throm...
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Ovarian venous varix

Ovarian venous varix is a situation where there is variceal dilatation of the ovarian vein (usually left). It can be associated with pelvic congestion syndrome. Radiographic features May be seen as a serpinginous structure adjacent to the aorta along the course of the ovarian vein.  
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Oxalosis

Oxalosis is supersaturation of calcium oxalate in the urine (hyperoxaluria), which in turn results in nephrolithiasis and cortical nephrocalcinosis.  This article focus on the secondary oxalosis, please refer to primary oxalosis for a specific discussion on this entity.  Pathology Calcium oxa...
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Pediatric cardiovascular procedures

A number of pediatric cardiovascular procedures are encountered when reporting pediatric imaging. They include: Blalock-Taussig (BT) shunt classic: end to side subclavian to ipsilateral pulmonary arterial anastomosis modified: graft anastomosis Waterston shunt Sano shunt: right ventricle to...
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Page kidney

Page kidney, or Page phenomenon, refers to systemic hypertension secondary to extrinsic compression of the kidney by a subcapsular collection, e.g. hematoma, seroma, or urinoma. Clinical presentation Patients present with hypertension, which may be recognized acutely after an inciting event or...
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Paget-Schrötter syndrome

Paget-Schrötter syndrome, alternatively spelled Paget-Schroetter syndrome and also known as effort thrombosis, refers to primary thrombosis of the axillary and/or subclavian vein. It can be thought of as a venous equivalent of thoracic outlet syndrome - i.e venous thoracic outlet syndrome. Epid...
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Palmar carpal branches

The two palmar carpal branches originate from the radial and ulnar arteries, respectively. They anastomose centrally, supporting the arterial supply of the anterior aspect of the wrist via their contribution to forming the palmar carpal arch 1. The palmar carpal branch of the ulnar artery trave...
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Pampiniform plexus

The pampiniform plexus (plural: plexuses) is the venous network of approximately 10 veins draining the testis and epididymis. The network surrounds the testicular artery in the spermatic cord and lies anterior to the ductus deferens. Each network coalesces to form the testicular (internal sperma...
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Pancreaticoduodenal veins

The pancreaticoduodenal veins accompany their corresponding arteries and act to drain the head of the pancreas and duodenum. Gross anatomy There are four small pancreaticoduodenal veins: posterior superior pancreaticoduodenal vein anterior superior pancreaticoduodenal vein posterior inferio...
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Pancreatic veins

The pancreatic veins drain blood from the body and tail of the pancreas. Gross anatomy The pancreatic veins comprise several small vessels that together act to drain the body and tail of the pancreas, and open into the great pancreatic vein. This subsequently drains into the splenic vein 1.
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Paracaval lipoma

Paracaval lipoma (a.k.a. juxtacaval fat collection or pseudolipoma of the inferior vena cava) is the apparent protrusion of paracaval fat into the inferior vena cava (IVC) and is commonly visible on CT; some believe it to be a normal anatomic variant 5.  Epidemiology Paracaval lipoma may be se...
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Paradoxical embolism

Paradoxical embolism is a clinical scenario in which an embolism arising in the venous system crosses into the arterial circulation where it causes tissue infarction. The most common clinically important site of embolization is the cerebral circulation. Epidemiology The prevalence of paradoxic...
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Paraumbilical veins

The paraumbilical veins are small veins around the falciform ligament that drain venous blood from the anterior part of the abdominal wall and diaphragm directly into the liver, and communicate with other anterior abdominal wall veins. This flow is considered the cause of focal fatty infiltratio...
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Parotid infantile hemangioma

Parotid infantile hemangiomas are the most common parotid tumor of childhood. They usually run a characteristically benign course. Epidemiology The median age at diagnosis is 4 months 1. There is a female preponderance with a male: female ratio of 1:3. Clinical presentation Presents as an en...
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Partial anomalous pulmonary venous return

Partial anomalous pulmonary venous return (PAPVR), also known as partial anomalous pulmonary venous connection (PAPVC), is a rare congenital cardiovascular condition in which some of the pulmonary veins, but not all, drain into the systemic circulation rather than in the left atrium. Clinical p...
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Particulate material pulmonary embolism

Particulate material pulmonary embolism (PE) is a type of non-thrombotic pulmonary embolism caused by a variety of non-organic particulate materials. Epidemiology Unlike bland thrombotic PE, non-thrombotic PE is uncommon. The exact incidence varies from one study to another, and very much depe...
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Peak systolic velocity (Doppler ultrasound)

Peak systolic velocity (PSV) is an index measured in spectral Doppler ultrasound. On a Doppler waveform, the peak systolic velocity corresponds to each tall “peak” in the spectrum window 1. Explanation When traveling with their greatest velocity in a vessel (i.e. during systole), red blood cel...
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Penetrating atherosclerotic ulcer

Penetrating atherosclerotic ulcers (PAU) are a pathology that involves the aortic wall. Along with aortic dissection and aortic intramural hematoma they can form the spectrum known as acute aortic syndrome.  Epidemiology Typically, penetrating atherosclerotic ulcers are seen in older male pati...
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Perforating veins of the lower limb

The perforating veins of the lower limb (PV or “perforators”) are so called because they perforate the deep fascia of muscles, to connect the superficial venous systems of the lower extremity with the deep veins where they drain. There are numerous veins in variable arrangement, connection, size...
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Perforators of the leg and calf (venae perforantes cruris)

The perforators of the leg (venae perforantes cruris; PV; or “perforating veins”) are a subset of, and not to be confused with, the larger overarching group of perforating veins of the lower limb. This group of veins connects the superficial venous systems and deep veins in the calf and are div...
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Peri-aneurysmal retroperitoneal fibrosis

Perianeurysmal retroperitoneal fibrosis is a subtype of a spectrum of retroperitoneal fibrosis. It is characterized by association with an inflammatory aneurysm, adventitial and periadventitial inflammation, medial thinning and chronic retroperitoneal inflammatory process which is associated wit...
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Pericallosal artery

The pericallosal artery is the distal portion of the anterior cerebral artery (ACA) that courses over the superior surface of the body of the corpus callosum in the pericallosal cistern. It gives off many small branches to the corpus callosum, forming the pericallosal moustache. Some authors de...
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Pericallosal moustache

The pericallosal moustache is formed by small branches from the pericallosal arteries and their accompanying veins. These form what appears to be an upturned poorly groomed moustache (not unlike Salvador Dali) and outline the superior surface of the corpus callosum (pericallosal cistern).
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Pericardial calcification

Pericardial calcification is usually seen in individual patients with a history of pericarditis and may be associated with constrictive pericarditis.  Pathology Although historically infective pericarditis was the most common cause, a wide variety of insults can lead to calcification of the pe...
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Pericardiophrenic artery

The pericardiophrenic artery, also known as the pericardiacophrenic artery, is a branch of the internal thoracic artery that runs to the diaphragm where it anastamoses with both the musculophrenic and superior phrenic arteries. It runs with the phrenic nerve and pericardiophrenic vein between th...
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Peripancreatic pseudoaneurysm

Peripancreatic pseudoaneurysm refers to the formation of a pseudoaneurysm around the pancreatic gland. It is a rare but potentially lethal complication 5. Epidemiology Formation of pseudoaneurysm can occur in as many as 10% of cases of pancreatitis. The time interval is variable, ranging from ...
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Peripheral arterial disease

Peripheral arterial disease (PAD) is a common and debilitating condition. Epidemiology The age-adjusted prevalence of peripheral arterial disease is ~12% 3. Pathology Atherosclerosis is the leading cause of occlusive arterial disease of the extremities in patients over 40 years of age with t...
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Peripheral arterial disease (summary)

This is a basic article for medical students and other non-radiologists Peripheral arterial disease (sometimes less accurately referred to as peripheral vascular disease) is a relatively common progressive disease of arterial degeneration that can result in a variety of symptoms. Reference art...
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Peripherally inserted central catheter

Peripherally inserted central catheters (PICCs), often incorrectly tautologically termed PICC lines, are a type of central venous catheter predominantly used amongst oncology patients and those with chronic diseases (e.g. cystic fibrosis). They offer the ability to have long-term central venous...
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Peroneal magnus artery

The peroneal magnus artery or peronea arteria magna (PAM) is a congenital variant of the arterial supply of the leg, where both the anterior and posterior tibial arteries are hypoplastic and a large dominant peroneal artery supplies the whole leg and foot. It is seen in up to 5% of people 1,3. ...
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Peroneal veins

The peroneal or fibular veins are the venae comitantes that run with the peroneal artery in the lateral compartment of the leg and receive tributaries from soleus and from superficial veins. They terminate in the posterior tibial vein.
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Persistent carotid-vertebrobasilar anastomoses

The persistent carotid-vertebrobasilar anastomoses are variant anatomical arterial communications between the anterior and posterior circulations due to abnormal embryological development of the vertebrobasilar system. They are named, with the exception of the proatlantal artery, using the crani...
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Persistent communications between the carotid and vertebrobasilar arteries (mnemonic)

A mnemonic to recall the persistent communications between the anterior (carotid) and posterior (vertebrobasilar) systems is: HOT Pepper Knowledge of these anatomical variants is important to avoid confusion with pathology and to prevent inadvertent injury during surgery. Mnemonic H: hypoglo...
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Persistent hypoglossal artery

A persistent hypoglossal artery is one of the persistent carotid-vertebrobasilar anastomoses. It is second in frequency to the trigeminal artery which is present approximately six times as often.  It arises from the distal cervical ICA, usually between C1 and C3. After passing through an enlarg...
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Persistent median artery of the forearm

The persistent median artery of the forearm is an accessory artery that arises from the ulnar artery in the proximal forearm and is a persistent embryological remnant of the axial artery that usually regresses by eight weeks gestation. Epidemiology It is present in ~10% (range 2.2-23%) of the ...
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Persistent otic artery

The persistent otic artery is one of the persistent carotid-vertebrobasilar anastomoses, although there is considerable controversy in regards to its existence. It is said to arise from the C2 (petrous) segment of the internal carotid artery within the carotid canal. This artery emerges from the...
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Persistent primitive trigeminal artery

Persistent primitive trigeminal artery (PPTA) is one of the persistent carotid-vertebrobasilar anastomoses. It is present in 0.1-0.6% of cerebral angiograms and is usually unilateral. In utero, the trigeminal artery supplies the basilar artery before the development of the posterior communicati...
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Persistent proatlantal intersegmental artery

The proatlantal intersegmental artery is also known as the type I proatlantal artery, and is one of the persistent carotid-vertebrobasilar anastomoses. It arises from the internal carotid artery (similar to the hypoglossal artery) but instead of heading for the hypoglossal canal, it joins the ve...
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Persistent right umbilical vein

A persistent right umbilical vein (PRUV) is an uncommon vascular anomaly which is often detected in utero. Epidemiology The estimated prevalence is ~2 per 1000 births 1,2. Pathology In the normal situation, the right umbilical vein begins to obliterate in the ~4th week of gestation and disap...
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Persistent sciatic artery

A persistent sciatic artery is a rare vascular anomaly where there is the persistence of the embryological axial limb artery, representing a continuation of the internal iliac artery into the thigh through the greater sciatic foramen below the piriformis muscle and down the thigh alongside the s...
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Persistent stapedial artery

The persistent stapedial artery (PSA) is an abnormal small vessel arising from the petrous portion of the internal carotid artery and crossing through the middle ear. It results from the failure of regression of the embryonic stapedial artery.  Epidemiology The prevalence is thought to range f...
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Personalised external aortic root support (PEARS)

Personalised external aortic root support (PEARS) is a procedure is where a computer designed mesh sleeve is manufactured to match the aortic root and aortic morphology of the individual patient and then placed to repair pathological aortic morphology such as those with Marfan syndrome. It was i...
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PHACE syndrome

PHACE syndrome, also known as cutaneous hemangioma–vascular complex syndrome or Pascual-Castroviejo type II syndrome, is a phakomatosis that comprises of: P: posterior fossa malformations (e.g. Dandy-Walker malformation) H: hemangiomas A: arterial anomalies C: coarctation of the aorta and ca...
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Phase contrast imaging

Phase contrast imaging is an MRI technique that can be used to visualize moving fluid. Basic principle Spins that are moving in the same direction as a magnetic field gradient develop a phase shift that is proportional to the velocity of the spins. This is the basis of phase-contrast angiograp...
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Phlebolith

Phleboliths are literally "vein stones", and represent calcification within venous structures. They are particularly common in the pelvis where they may mimic ureteric calculi, and are also encountered frequently in venous malformations. There is an association with Maffucci syndrome.  Radiogra...
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Phlegmasia cerulea dolens

Phlegmasia cerulea dolens (PCD) is an uncommon complication of deep venous thrombosis, which results from extensive thrombotic occlusion of the major and collateral veins of an extremity (usually the legs). Epidemiology Left leg is more commonly affected than the right 4. Risk factors Risk f...
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Pinch off syndrome

Pinch-off syndrome is a spontaneous catheter fracture, which is seen as a complication of subclavian venous catheterization. Epidemiology It is a known complication of central venous catheterization with a much-reduced incidence in current practice and is generally considered to be rare. Radi...
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PISAPED criteria for diagnosis of pulmonary embolus

The PISAPED criteria for the diagnosis of pulmonary embolus indicate the presence or absence of pulmonary emboli based on findings on perfusion scintigraphy (only the Q portion of the V/Q scan) in combination with chest radiography. The criteria were validated in the Prospective Investigative St...
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Placental chorioangioma

Placental chorioangiomas are benign vascular tumors of placental origin. It is the most common tumor of the placenta and is usually found incidentally. Epidemiology The estimated incidence is at ~1% of all pregnancies 3. Clinical presentation In most cases, chorioangiomas are asymptomatic, a...
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Plexogenic arteriopathy

Plexogenic arteriopathy has been a term used to describe a constellation of vascular changes occurring in those with pulmonary arterial hypertension. It is considered the histologic hallmark of idiopathic pulmonary arterial hypertension; it is seen in approximately 75% of cases 3. The term for t...
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Polo mint sign (venous thrombosis)

The polo mint sign is a description given to a venous thrombosis on contrast-enhanced CT imaging.  When viewed in the axial plane, a thin rim of contrast persists around a central filling defect due to thrombus. This gives an appearance like that of the popular UK mint sweet, the Polo (figure 1)...
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Polyarteritis nodosa

Polyarteritis nodosa (PAN) is a systemic inflammatory necrotizing vasculitis that involves small to medium-sized arteries (larger than arterioles).  Epidemiology PAN is more common in males and typically presents around the 5th to 7th decades. 20-30% of patients are hepatitis B antigen positiv...
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Polymyositis (pulmonary manifestations)

Lung involvement in polymyositis can have a number of manifestations including those resembling interstitial lung disease. For a general discussion of polymyositis, please refer to the parent article. Radiographic features The lungs may present with a mixture of different fibrotic patterns, e...
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Pontine arteries

The pontine branches are the small arterial branches of the basilar artery that supply the pons and structures adjacent to the pons. There are usually 3-5 paired arterial branches which are located in the mid-basilar region between the anterior inferior cerebellar artery and the superior cerebe...
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Popliteal artery

The popliteal artery is the direct continuation of the superficial femoral artery, at the point where it exits the adductor canal at the adductor hiatus, and passes into the popliteal fossa as the vessel courses posteriorly behind the knee. Summary origin: continuation of the superficial femor...
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Popliteal artery aneurysm

Popliteal artery aneurysms are the most common peripheral arterial aneurysm and the second most common aneurysm after abdominal aortic aneurysms. Epidemiology Overall, popliteal artery aneurysms are uncommon. They occur almost exclusively in males (up to 97%) for unknown reasons 8-9. There is ...
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Popliteal artery entrapment syndrome

Popliteal artery entrapment syndrome refers to symptomatic compression or occlusion of the popliteal artery due to a developmentally abnormal positioning of the popliteal artery in relation to its surrounding structures such as with the medial head of gastrocnemius or less commonly with popliteu...
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Popliteal fossa

The popliteal fossa (plural: fossae) is a diamond or rhomboid-shaped fat-filled space in the posterior knee. The space is extremely dynamic, allowing for its neurovascular contents to move during the extreme range of motion produced by knee flexion and extension. Gross anatomy Boundaries supe...
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Popliteal vein

The popliteal vein forms from the posterior and anterior tibial veins and ascends through the popliteal fossa to the opening in adductor magnus alongside the popliteal artery where it becomes the femoral vein. Its relationship to the popliteal artery changes as the vein ascends, but it is alway...
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Popliteal venous aneurysm

Popliteal venous aneurysms are rare than those of the popliteal artery and are mostly asymptomatic. However, due to the disturbance of the venous blood flow, they can lead to potentially life-threatening consequences, such as deep vein thrombosis (DVT) and pulmonary embolism (PE). Epidemiology ...
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Porcelain aorta

A porcelain aorta refers to circumferential calcification of the ascending aorta. This finding is important to recognize in the preoperative evaluation of cardiac surgery as it complicates cardiac surgeries that require cross-clamping or accessing the aorta (such as open aortic valve replacement...
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Portal hypertension

Portal hypertension is defined as hepatic venous pressure gradient (HVPG) greater than 5 mmHg. HVPG is a surrogate for the portosystemic pressure gradient. Clinically significant portal hypertension is defined as a gradient greater than 10 mmHg and variceal bleeding may occur at a gradient great...
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Portal hypertensive gastropathy / enteropathy / colopathy

In portal hypertension, chronic portal venous congestion leads to dilatation and ectasia of the submucosal vessels in the stomach (portal hypertensive gastropathy), small bowel (portal hypertensive enteropathy) and/or large bowel (portal hypertensive colopathy). This may result in upper or lower...
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Portal vein

The portal vein (PV) (sometimes referred to as the main or hepatic portal vein) is the main vessel in the portal venous system and drains blood from the gastrointestinal tract and spleen to the liver. Gross anatomy The portal vein usually measures approximately 8 cm in length in adults with a ...
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Portal vein calcification

Portal vein calcification is a rare radiologic finding which can be seen in long-standing portal venous hypertension. Pathology Calcium may be deposited in a thrombus or in the wall of the portal vein and is more rarely found in the splenic vein and superior mesenteric vein. One of the propos...
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Portal vein embolization

Portal vein embolization (PVE) is a technique used to selectively occlude the blood supply to one of the liver lobes, diverting portal blood flow to the other lobe, the future liver remnant (FLR). This diversion will increase the size of the post-hepatectomy future liver remnant, which improves...
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Portal vein thrombosis

Portal vein thrombosis may be seen in a variety of clinical contexts, and when acute can be a life-threatening condition. It is a major cause of non-cirrhotic presinusoidal portal hypertension. Portal vein thrombus may be either bland and/or malignant (i.e. tumor thrombus), and it is a critical ...
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Portal venous gas

Portal venous gas is the accumulation of gas in the portal vein and its branches. It needs to be distinguished from pneumobilia, although this is usually not too problematic when associated findings are taken into account along with the pattern of gas (i.e. peripheral in portal venous gas, centr...
Article

Portal venous system

The portal venous system refers to the vessels involved in the drainage of the capillary beds of the GI tract and spleen into the capillary bed of the liver. Blood flow to the liver is unique in that it receives both oxygenated and deoxygenated blood. As a result, the partial pressure of oxygen...
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Portal venous varix

A portal venous varix (plural: portal venous varices) refers to a segments of aneurysmal / variceal dilatation of the portal vein are extremely rare and represent only 3% of all aneurysms of the venous system. They are still however the most common visceral varix 8. Clinical presentation Most ...
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Portosystemic collateral pathways

Portosystemic collateral pathways (also called varices) develop spontaneously via dilatation of pre-existing anastomoses between the portal and systemic venous systems. This facilitates shunting of blood away from the liver into the systemic venous system in portal hypertension, as a means for r...
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Portosystemic shunt ratio

The portosystemic shunt ratio is a measure performed using ultrasound to quantify the abnormal flow of portal venous blood that is shunted away from the hepatic sinusoidal circulation in the context of a congenital portosystemic shunt 1. Measurement The ratio is determined on ultrasound using ...
Article

Post-embolization syndrome

Post-embolization syndrome (PES) is one of the most common complications of transarterial embolization and chemoembolisation. The condition comprises a constellation of symptoms including pain, fever, nausea and vomiting. PES usually occurs within the first 72 hours after solid organ embolizatio...
Article

Posterior auricular artery

The posterior auricular artery is a branch of the external carotid artery and supplies scalp posterior to the auricle and the auricle itself. Summary origin: branch of the external carotid artery above digastric and stylohyoid opposite the styloid process course: ascends beneath the parotid t...
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Posterior auricular vein

The posterior auricular vein is tributary of the external jugular vein or retromandibular vein. Gross anatomy Origin and course It arises over the mastoid process of the temporal bone draining the skin behind the ear and courses anteriorly into the parotid gland, draining into the external ju...
Article

Posterior cerebral artery

The posterior cerebral arteries (PCA) are the terminal branches of the basilar artery and supply the occipital lobes and posteromedial temporal lobes. Summary origin: terminal branches of the basilar artery course: from basilar towards occiput main branches posterior communicating artery m...
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Posterior cerebral artery (PCA) infarct

Posterior cerebral artery (PCA) infarcts arise, as the name says, from occlusion of the posterior cerebral artery. It is a type of posterior circulation infarction. Clinical presentation Symptoms of posterior cerebral artery stroke include contralateral homonymous hemianopia (due to occipital ...
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Posterior cerebral circulation

The posterior cerebral circulation (or simply, posterior circulation) is the blood supply to the posterior portion of the brain, including the occipital lobes, cerebellum and brainstem. Due to the anastomotic circle of Willis, the posterior circulation connects via the posterior communicating a...
Article

Posterior choroidal artery

The posterior choroidal artery is not in fact a single artery, although it is commonly referred to as such. The posterior choroidal arteries, often numbering up to 10 or 11 per hemisphere, are divided into medial posterior choroidal artery and lateral posterior choroidal artery groups. They usua...
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Posterior choroidal artery stroke

Posterior choroidal artery occlusion uncommonly presents as an isolated stroke syndrome.  It usually coexists with posterior cerebral artery and often superior cerebellar artery involvement.  When seen in isolation damage is characteristically limited to the: lateral geniculate body pulvinar ...

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