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53 results found

Cauldwell Classification

Cauldwell classification is a commonly used classification in assessing bronchial artery branching pattern. Classification The bronchial artery branching pattern is classified into four types based on the number of intercostobronchial trunks (ICBT) - that gives rise to right bronchial artery a...

Contraceptive implant migration

Contraceptive implant migration is a rare complication of etonogestrel implant insertion. Clinical presentation unable to palpate device in the upper arm chest pain dyspnea non-productive cough menorrhagia irregular vaginal bleeding Pathology Contraceptive implants are most commonly in...

Billowing phenomenon

Billowing phenomenon refers to the presence of contrast medium on contrast-enhanced CT outside of graft metal struts, due to the specific construction characteristic typical of the AFX® stent-graft (Endologix, Inc., USA), designed to treat abdominal aortic aneurysms. It has a unique internal sca...

Inferior vena cava filter retrieval

Inferior vena cava filter retrieval is an endovascular procedure whereby a previously placed inferior vena cava (IVC) filter is removed. Procedure The procedure is performed under local anesthesia with fluoroscopic guidance. Venous access is usually gained via the internal jugular vein with di...

Endovascular arteriovenous fistula creation

Endovascular arteriovenous fistula creation is a recently developed minimally invasive alternative for the creation of arteriovenous fistulae for haemodialysis access. Technique Catheter-based technology and image guidance in the form of ultrasound and fluoroscopy is utilized create a side-to-...

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. ...

Implantable port

Implantable ports, also known as chemoports, totally implantable central venous access ports or Port-A-Caths®, are a type of central venous catheter for patients requiring long-term venous access. They offer the ability to have long-term central venous access with some of the advantages over per...

Balloon-occluded retrograde transvenous obliteration

Balloon-occluded retrograde transvenous obliteration (BRTO) is a technique used by interventional radiologists in the treatment of gastric varices, particularly those with prominent infra-diaphragmatic portosystemic venous shunts (e.g. gastro-renal and gastro-caval shunts). The technique is mor...

Charles T Dotter

Charles T Dotter (1920-1985) is often considered the father of interventional radiology who in 1964 performed the very first peripheral angioplasty, and made many other major contributions in this field. Early life Charles Theodore Dotter was born in Boston on 14 June 1920. He graduated with a...

Hickman catheter

Hickman catheters (or Hickman lines) are a type of tunnelled central venous access line. Indications chemotherapy administration 2 parenteral nutrition 2 long-term parenteral antibiotic administration 2 Complications Insertion arrhythmia (most common) 1 arterial injury kinking pneumoth...

Needle gauge system

The needle gauge system, often called just the Gauge or G, is an internationally-used scale for sizing needles. It was adopted from pre-existing gauges which were used in industry to size metal wire. In contradistinction to the French scale, the other well-known sizing system, which is a metric...

French gauge

The French gauge (Fr) (also known as the French scale or system) is used to size catheters, and other instruments, in interventional radiology and surgery. In some parts of the world, the Charrière (Ch) is used as the name of the unit, in honor of its inventor. French sizing The French system...

Coronary Artery Disease - Reporting and Data System

The Coronary Artery Disease - Reporting and Data System (CAD-RADS) is a standardized findings communication method and clinical decision aid relevant to coronary CT angiography. The system was created by a collaboration of the Society for Cardiovascular Computed Tomography (SCCT), American Colle...

Type III endoleak

A type III endoleak is a type of endoleak which usually occurs through a defect in the graft. It may be divided into two components. IIIa: junctional separation of the modular components IIIb: fractures or holes involving the endograft Epidemiology It is relatively uncommon and only occurs ...

Pulmonary artery catheter

Pulmonary artery catheters (or Swan-Ganz catheters) are balloon flotation catheters that can be inserted simply, quickly, with little training and without fluoroscopic guidance, at the bedside, even in the seriously ill patient, into the pulmonary arteries. Usage Historically, pulmonary artery...

Basilar artery aneurysm

Basilar artery aneurysms are less common than anterior circulation aneurysms, and rupture less frequently, but their critical location necessitates careful evaluation. Unruptured basilar artery aneurysms occurs in 3% of all intracranial aneurysms 4. Radiographic features CT may present as ...

Catheter-directed thrombolysis

Catheter-directed thrombolysis (CDT) is an endovascular approach to the treatment of acute iliofemoral deep vein thrombosis. It involves the administration of a lytic agent directly into a thrombus. Indications precise diagnosis of iliofemoral deep vein thrombosis first episode of acute ili...

Post-thrombotic syndrome

Post-thrombotic syndrome (PTS) is a syndrome of chronic venous insufficiency following deep vein thrombosis (DVT) due to valvular incompetence, which results in chronic reflux and chronic venous hypertension. Epidemiology PTS is a common complication following extensive DVT of the limbs. Up to...

Endovascular aneurysm sealing system (EVAS)

Endovascular aneurysm sealing system (EVAS) was developed with the intention to expand beyond the anatomic limitations of endovascular aneurysm repair (EVAR) devices, as well as to decrease the rates of re-intervention secondary to graft migration and type II endoleaks. EVAS was designed by End...

Hepatic venous pressure gradient

Hepatic venous pressure gradient measurement is a safe and minimally invasive method to indirectly measure portal vein pressure in chronic liver disease patients suspected of developing portal vein hypertension. Indications diagnosis of liver fibrosis and risk stratification identification o...

Multiphase CT angiography in acute ischemic stroke

Multiphase CT angiography is an evolving imaging technique in acute ischemic stroke. The technique aims to quickly and reliably identify brain which is potentially salvageable with intervention. Brain tissue viability depends on many factors, with this technique assessing collateral leptomeninge...

Double lumen cannula for VV ECMO

The double lumen cannula enables veno-venous extracorporeal membrane oxygenation (VV ECMO) to patients with severe respiratory failure. It is often used as a bridge to lung transplant. The cannulation is usually performed via the right jugular vein. This position allows the patients to stay aw...

Ultrasound-guided peripheral intravenous cannulation

Peripheral intravenous cannulation under ultrasound guidance is the placement of a cannula into a peripherally-located vein under the direct vision of ultrasound. This process allows the cannulation of veins that are unable to be visualized or palpated without ultrasound. In trained individuals ...

Infusothorax

Infusothorax (plural: infusothoraces), also known as a chemothorax, is a complication of central venous catheter malposition where the catheter tip is located in the pleural space and the infusion of the fluid collects inadvertently in the pleural space in the form of a pleural effusion. Longer ...

Arteriovenous access

Arteriovenous access is required for haemodialysis in renal failure patients. The upper limb is generally preferred as a site, however, lower limb access can also be obtained. Ultrasound is the preferred modality for evaluation of the vessels prior to creating an access. Types arteriovenous fi...

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...

Renal artery pseudoaneurysm

Renal artery pseudoaneurysms are uncommon vascular finding, with the majority occuring after a renal intervention. Pathology A renal artery pseudoaneurysm differs from a renal artery true aneurysm (as might occur in fibromuscular dysplasia) in that it does not involve all three layers of the a...

TIPS evaluation

TIPS evaluation is useful to ensure that a transjugular intrahepatic portosystemic shunt (TIPS) is working properly and that no stenosis has occurred within the stent. Ultrasound is often used as a first-line modality. Radiographic features Ultrasound The normal TIPS should show color Doppler...

Renal sympathetic denervation

Renal sympathetic denervation (RSDN), also known as renal denervation, is an interventional procedure that uses radiofrequency ablation to destroy the nerve endings in the wall of the renal arteries. Endovascular (trans-catheter) techniques are an alternative to surgical sympathectomy. Indicat...

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...

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 ...

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...

Adrenal vein sampling

Adrenal vein sampling (AVS) is a procedure where blood is collected from the adrenal veins via catheter to confirm autonomous hormone production, if it is unilateral or bilateral, and to guide further treatment. Indication Adrenal vein sampling is commonly performed in primary aldosteronism, b...

Prostatic artery embolization

Prostatic artery embolization (PAE) is a minimally invasive procedure utilized to treat benign prostatic hyperplasia (BPH). Indications PAE has been used for controlling prostatic hemorrhage (such as that associated prostate cancer) since 1970. However, its use in the treatment of lower urina...

Rotational vertebral artery occlusion syndrome

Rotational vertebral artery occlusion syndrome, also known as bow hunter's syndrome, is a rare form of vertebrobasilar insufficiency secondary to dynamic compression of the usually-dominant vertebral artery. Pathology It has many predisposing etiologies, but is most often due to large osteoph...

Central venous catheter

Central venous catheters (CVC), also known as central venous lines (CVL), refer to a wide range of catheters that are inserted so that their distal tips lie in a central vein. Central venous access devices can broadly be divided into four categories. They may be inserted by medical, surgical, an...

Antonio Egas Moniz

Antonio Egas Moniz (1874-1955) 1 was a pioneering Portuguese neurologist that is notable in radiology history for his development of cerebral angiography in 1927. He is also known as the developer of prefrontal leucotomy (now better known as a lobotomy) for which he received a Nobel Prize in 1...

Inferior vena cava filter

Inferior vena cava filter, or just IVC filter, is an endovascular device which is typically placed in the infrarenal inferior vena cava (IVC) to prevent pulmonary embolism in selected patients. This procedure is most often performed by interventional radiologists under fluoroscopic guidance. In...

Intra-aortic balloon pump

Intra-aortic balloon pumps (IABP) are used in the intensive care setting to provide hemodynamic assistance to patients in cardiogenic shock. Function and physiology The device is comprised of a catheter introduced via a femoral artery sheath, which extends retrogradely to the proximal descendi...

Femoral artery pseudoaneurysm

Femoral artery pseudoaneurysms are usually iatrogenic, as the femoral artery is the vessel of choice for most endovascular arterial interventions. Pathology Etiology iatrogenic anticoagulation therapy inadequate compression following femoral arterial puncture for endovascular intervention ...

Retroaortic left renal vein

Retroaortic left renal vein (RLRV) is a normal anatomical variant where the left renal vein is located between the aorta and the vertebra and drains into the inferior vena cava. Its recognition is important in order to avoid complications during retroperitoneal surgery or interventional procedu...

Carotid arterial stenting

Carotid arterial stenting (CAS) is a minimally invasive endovascular interventional procedure that can potentially offer the same advantage as surgery (carotid endarterectomy). Indications Indications for carotid stenting are evolving with endarterectomy trials that evaluate the carotid stenos...

Uterine artery embolization

Uterine artery embolization (UAE) is an interventional radiological technique to occlude the arterial supply to the uterus and is performed for various reasons. History Uterine artery embolization has been practised for more than 20 years for controlling hemorrhage following delivery/abortion,...

Jugular venous catheters

The internal jugular vein is a preferred site for venous access for large lumen, long-term central venous catheters for chemotherapy, hemofiltration and plasma exchange. These are commonly referred to as (internal) jugular venous (IJV) catheters. Typically, the right internal jugular is used as...

Left paramediastinal catheter position (differential)

When a central venous catheter that is supposed to terminate in the superior vena cava or right atrium is abnormally located to the left of the mediastinum and below the level of the brachiocephalic vein, a limited differential of left paramediastinal catheter position should be considered 1: l...

Transjugular intrahepatic portosystemic shunt

Transjugular intrahepatic portosystemic shunt (TIPS or TIPSS) is a treatment for portal hypertension in which direct communication is formed between a hepatic vein and a branch of the portal vein, thus allowing some proportion of portal flow to bypass the liver. The target portosystemic gradient...

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...

Endotension

Endotension, also referred to as a type V endoleak, is not a true leak but is defined as continued expansion of the aneurysm sac greater than 5 mm, without radiographic evidence of a leak site. Pathology It is a poorly understood phenomenon but thought to be formation of a transudate due to ul...

Varicocele

Varicocele is the dilatation of the pampiniform plexus of veins, a network of many small veins found in the male spermatic cord. It is the most frequently encountered mass of the spermatic cord. Epidemiology The estimated incidence is at ~15% of the general male population and ~40% of subferti...

Call-Fleming syndrome

Call-Fleming syndrome, also called Call syndrome, essentially synonymous with the more current term reversible cerebral vasoconstriction syndrome (RCVS), although it is felt to be a subset of the former by some, representing the idiopathic RCVS. Call-Flemming syndrome is therefore characterize...

Endovascular aneurysm repair

Endovascular aneurysm repair (EVAR) was first pioneered in the early 1990s. Since then the technology of the devices has rapidly progressed and EVAR is now widely used as a treatment of thoracic and abdominal aortic aneurysms (AAA). The advantages of endovascular repair over open repair are tha...

Endoleak

Endoleaks are characterized by persistent blood flow within the aneurysm sac following endovascular aneurysm repair (EVAR). Normally the aortic stent-graft used for EVAR excludes the aneurysm from the circulation by providing a conduit for blood to bypass the sac. Epidemiology An endoleak is a...

May-Thurner syndrome

May-Thurner syndrome refers to a chronic compression of the left common iliac vein (CIV) against the lumbar vertebrae by the overlying right common iliac artery (CIA), with or without deep venous thrombosis 2. Although both left and right CIVs lie deep to the right common iliac artery, the left...

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