Articles

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16,686 results found
Article

Hemobilia

Hemobilia refers to the presence of blood in the biliary tree. Clinical presentation The classical Quincke triad, is seen with hemobilia in the context of hepatic arterial aneurysms, and consists of: melena (i.e. upper gastrointestinal bleeding) jaundice abdominal pain Pathology Etiology ...
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Quincke triad

Quincke triad is the finding of jaundice, right upper quadrant pain, and upper gastrointestinal bleeding. This sign is seen in patients with hemobilia secondary to a hepatic artery aneurysm. History and etymology Heinrich Quincke (1842 –1922) was a German surgeon and internal medicine speciali...
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Gallbladder metastases

Gallbladder metastases are rare and usually represent an advanced and end-stage of malignancy. Malignant melanoma and gastric carcinoma account for the most common primary malignancies to seed metastases to the gallbladder, in Western and Asian societies, respectively.  Epidemiology They repre...
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Endometrial polyp

Endometrial polyps are benign nodular protrusions of the endometrial surface, and one of the entities included in a differential of endometrial thickening. Endometrial polyps can either be sessile or pedunculated. They can often be suggested on ultrasound or MRI studies but may require sonohyste...
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Endometriosis

Endometriosis is a common, chronic gynecological condition defined as the presence of functional endometrial glands and stroma-like lesions outside the uterus. It manifests in three ways: superficial (peritoneal) disease, ovarian disease (endometriomas), and deep endometriosis. Endometriosis is...
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Adrenal adenoma

Adrenal adenomas (alternative plural: adenomata) are the most common adrenal lesion and are often found incidentally during abdominal imaging for other reasons. In all cases, but especially in the setting of known current or previous malignancy, adrenal adenomas need to be distinguished from adr...
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p-value

A p-value is the probability of observing a difference between groups at least as extreme as what was observed. Since a p-value is calculated assuming that the null hypothesis (H0) is true, the expectation is that there is no difference between the groups being evaluated. The process of evaluati...
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Diffusion kurtosis imaging

Diffusion kurtosis imaging (DKI) is an advanced neuroimaging modality which is an extension of diffusion tensor imaging by estimating the kurtosis (skewed distribution) of water diffusion based on a probability distribution function. It provides a high order diffusion of water distribution and a...
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Aneurysmal bone cyst

Aneurysmal bone cysts (ABC) are benign expansile osteoclastic giant cell-rich bony neoplasms, composed of numerous blood-filled channels and cystic spaces 1. ABC accounts for the 'A' in the popular mnemonic for lucent bone lesions FEGNOMASHIC. Terminology The terms 'giant cell reparative gran...
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11-13 week antenatal scan

11-13 week antenatal (nuchal translucency) scan is considered a routine investigation advised for fetal well-being as well as for early screening in pregnancy (see antenatal screening). It includes multiple components and is highly dependent on the operator. Traditionally three factors are used...
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Acute appendicitis

Acute appendicitis is an acute inflammation of the vermiform appendix. It is a very common condition in general radiology practice and is one of the main reasons for abdominal surgery in young patients. CT is the most sensitive modality to detect appendicitis. Terminology Acute appendicitis (p...
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Jugulotympanic paraganglioma

Jugulotympanic paragangliomas (previously known as glomus jugulotympanicum tumors) are jugular paragangliomas that have spread superiorly to involve the middle ear cavity. The term can also be used clinically when a suspected tympanic paraganglioma involves the hypotympanum as its inferior exten...
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Right atrium

The right atrium (RA) (plural: atria) is one of the four chambers of the human heart, and is the first chamber to receive deoxygenated blood returning from the body, via the two venae cavae. It plays an important role in originating and regulating the conduction of the heart. Gross anatomy The...
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Lung cancer screening

Lung cancer screening with low-dose CT (LDCT) is an imaging strategy that is beginning to be adopted for high-risk patients in some health systems. Lung cancer is the most common cause of cancer death worldwide, and there is accumulating higher level evidence that a mortality benefit exists with...
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Complications of sleeve gastrectomy

Complications of sleeve gastrectomy​ are often evaluated by imaging. For details about the surgical procedure, please see the parental article on sleeve gastrectomy.  Complications Postoperative complications can be classified by etiology or temporality. Early complications staple line leaka...
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Hypothesis testing

Hypothesis testing is a statistical method used to evaluate clinical trial results and consists of 4 steps. Step 1 Specify the null hypothesis (H0) and the alternative hypothesis (HA). The null hypothesis is that there is no difference between groups being evaluated, while the alternative hypo...
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Skull vault hemangioma

Skull vault hemangiomas (SVH), or hemangiomas of the calvaria, are benign slow-growing vascular lesions affecting the skull diploe in any location. They have been more recently renamed osseous venous (low-flow) vascular malformations given their nonneoplastic nature, but "hemangioma" remains com...
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Paraurethral duct cyst

Paraurethral duct cysts are retention cysts that form secondary to inflammatory obstruction of the paraurethral (Skene) ducts in females. Pathology The cysts are lined by stratified squamous epithelium due to their origin from the urogenital sinus. Clinical presentation Usually asymptomatic....
Article

Endophthalmitis

Endophthalmitis (plural: endophthalmitides) is a potentially sight-threatening condition that involves intraocular inflammation of any cause. It is distinguished from panophthalmitis in that it does not extend beyond the sclera. It is either infectious or non-infectious in etiology, but in clini...
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Posterior cruciate ligament avulsion fracture

Posterior cruciate ligament (PCL) avulsion fractures are a type of avulsion fracture of the knee that represent the most common isolated PCL lesion. This typically involves the separation of the posterior tibial insertion of the PCL to variable degrees. Pathology These injuries are commonly se...

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