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203 results found

Ulnar nerve block (ultrasound-guided)

Ulnar nerve blocks are an approach for delivering anesthesia to the ulnar nerve territory either as a standalone blockade or combined with brachial plexus, radial or median nerve block. Indications burns involving tissue in the ulnar nerve territory rescue analgesia for failed brachial plexus...

Ultrasound-guided biopsy

Ultrasound-guided biopsy is one form of image-guided biopsy, typically performed by a radiologist. It is the most common form of image-guided biopsy, offering convenience and real-time dynamic observation with echogenic markers on cannulae allowing for precise placement. It can potentially be u...

Ultrasound guided breast biopsy

Ultrasound-guided percutaneous breast biopsy is a widely used technique for an accurate histopathological assessment of suspected breast pathology. It is a fast, safe and economical procedure. Indications Ultrasound guidance is limited to lesions visible on ultrasound study. The biopsy is gene...

Ultrasound-guided FNA of the thyroid

Ultrasound-guided fine needle aspiration (FNA) of the thyroid refers to a minimally invasive procedure where in which tissue samples are collected from a thyroid nodule or other suspicious thyroid lesion. It is usually done on a outpatient basis and generally complications are very minimal. Pro...

Ultrasound guided percutaneous drainage

Ultrasound guided percutaneous drainage is one form of image guided procedure, allowing minimally invasive treatment of collections that are accessible by ultrasound study. It has several advantages and disadvantages over CT, which include: Advantages is a dynamic study, allowing greater prec...

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 ...

Ultrasound-guided spinal anesthesia

With the growing incidence of obesity in the western world, ultrasound-guided anesthesia is becoming more common. Spinal anesthesia is traditionally administered by identifying relevant surface anatomy and imaging is rarely used for pre-procedural identification of structures.  Indications low...

Upper gastrointestinal bleeding

Upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz. Epidemiology The incidence of acute upper GI bleeding is ~100 per 100,000 adults per year. Upper GI bleeding is twice as common in men as in women and increases in prevalence with age 5. The demog...

Ureteric stent

Ureteric stents, also known as double J stents, JJ stents or retrograde ureteric stents, are urological catheters that have two "J-shaped" (curled) ends, where one is anchored in the renal pelvis and the other inside the bladder. Stents are used for the free passage of urine from the kidney to ...

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,...

Uterine artery embolization: MRI assessment

Uterine artery embolization (UAE) is used as an alternative to hysterectomy in selected patients and MRI assessment is key in allowing not only pre-procedure assessment but also assessing post-procedural outcome.   For a general discussion of the underlying condition refer to the article on ute...


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...

Varicocele embolization

Varicocele embolization is a minimally invasive method of treating varicoceles by embolizing the testicular vein (internal spermatic veins). Indications symptomatic varicocele infertility/subfertility failed surgical ligation Contraindications Relative contraindications include: intraveno...

Venous intravasation

Venous intravasation is the unintended introduction of radiographic contrast material into the local venous system. It is a well-recognized phenomenon during retrograde urethrograms 1,2 and hysterosalpingograms (HSG), although can occur with other invasive procedures in the vicinity of venous pl...


Vertebroplasty is an imaging-guided procedure which entails percutaneous injection of surgical polymethylmethacrylate (PMMA) cement into a diseased vertebral body. Vertebroplasty provides pain relief and strengthening of the bone of vertebrae weakened by disease. Indications It can be used as ...


The viscera (singular: viscus) refers to all the internal organs within the major cavities of the thorax, abdomen and pelvis. Therefore it does not include organs of the CNS, head and neck or musculoskeletal compartments nor does it encompass non-internal organs (e.g. the skin) 1. Splanchnology...

Winslow pathway

The Winslow pathway is a type of collateral vessel communication which connects the mammary arteries through the internal thoracic arteries to the inferior epigastric arteries and then into the external iliac arteries. It may recanalize in conditions such as aortoiliac occlusive disease.

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