Articles

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...

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...

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...

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...

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...

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...

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...

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...

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...

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....

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...

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...

The grey matter heterotopias are a relatively common group of conditions characterized by interruption of normal neuronal migration from near the ventricle to the cortex, thus resulting in "normal neurons in abnormal locations" 2. They are a subset of disorders of cortical formation 3,4. Grey m...

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...

Extension teardrop fracture typically occurs due to forced extension of the neck with resulting avulsion of the anteroinferior corner of the vertebral body. Extension teardrop fractures are stable in flexion and unstable in extension as the anterior longitudinal ligament is disrupted. Extension ...

The anterior cerebral artery (ACA), along with the middle cerebral artery (MCA) forms at the termination of the internal carotid artery (ICA). It is the smaller of the two and arches anteromedially to pass anterior to the genu of the corpus callosum, dividing as it does so into its two major bra...

Probability is the likelihood of a random outcome (called an “event”) and is written as P(event)= x, where x is a number ≥0 and ≤1. Using this notation, the probability of rolling a 2 with a fair 6-sided die is written as P(2)=1/6. A probability of 0 means that an event is impossible while a pro...

Rectal diverticulosis (plural: diverticuloses) or the presence of diverticula in the rectum is very rare. Epidemiology Rectal diverticula are very rare with only scattered case reports in the global medical corpus, and symptomatic cases, e.g. rectal diverticulitis, are even rarer 1. It has bee...

Prothrombin 20210 mutation is a prothrombotic hematological condition which predisposes individuals to thromboembolic events such as deep venous thrombosis cerebral venous thrombosis cerebrovascular events pulmonary embolism Epidemiology It is considered the second most commonly inherited ...

Paraduodenal hernias are internal hernias due to failure of the descending or ascending colonic mesentery to fuse with the posterior parietal peritoneum. Left paraduodenal hernia is more common and can cause closed-loop bowel obstruction and infarction. Clinical presentation The patient may h...