Articles
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16,854 results found
Article
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...
Article
≤11 ribs (differential)
≤11 ribs is associated with a number of congenital abnormalities and skeletal dysplasias, including:
Down syndrome (trisomy 21)
campomelic dysplasia
kyphomelic dysplasias
asphyxiating thoracic dysplasia (Jeune syndrome)
short rib polydactyly syndromes
trisomy 18
chromosome 1q21.1 deletion...
Article
1-2-3 rule (ovary)
The 1-2-3 rule is a simple aide-mémoire describing the nomenclature of any small simple anechoic structure in the ovary on ultrasound:
<1 cm = follicle
1-2 cm = dominant follicle
>3 cm = cyst
Article
12q14 microdeletion syndrome
12q14 microdeletion syndrome or osteopoikilosis-short stature-intellectual disability syndrome is caused by heterozygous deletion at the region of 12q14. The microdeletion affects the LEMD3 gene which has already been implicated in osteopoikilosis.
Epidemiology
Prevalence is <1 in 1 million li...
Article
14-3-3 protein
14-3-3 proteins are found in the cerebrospinal fluid (CSF) and are currently used to help identify patients with sporadic Creutzfeldt-Jakob disease (sCJD).
Seven distinct 14-3-3 proteins have been found in humans.
In diagnosing sCJD, the sensitivity of 14-3-3 protein is 92%, and its specifici...
Article
1.5 T vs 3.0 T
Comparing 1.5 T vs 3.0 T (1.5 tesla vs 3.0 tesla) MRI systems identifies several differences; a 3 T system has
increased signal-to-noise ratio (SNR)
increased spatial resolution
increased temporal resolution
increased specific absorption rate (SAR)
increased acoustic noise
Terminology
It...
Article
18q deletion syndrome
18q deletion syndrome is a rare chromosomal anomaly where there is a deletion of part of the long arm of chromosome 18. Associated symptoms and findings vary widely, as do their severity. Characteristic clinical features include short stature, intellectual disability, hypotonia, facial, and dist...
Article
1p19q codeletion
1p19q codeletion stands for the combined loss of the short arm chromosome 1 (i.e. 1p) and the long arm of chromosome 19 (i.e. 19q) and is recognized as a genetic marker predictive of therapeutic response to both chemotherapy and combined chemoradiotherapy and overall longer survival in patients ...
Article
1p36 deletion syndrome
1p36 deletion syndrome, or monosomy 1p36, is a chromosomal abnormality characterized most commonly by a deletion in the distal segment of the short arm of chromosome one 1.
Epidemiology
The 1p36 deletion syndrome is present in approximately 1 in 5,000 live births. It is the most common termina...
Article
2001 WHO classification of hepatic hydatid cysts
The 2001 World Health Organizatiοn (WHO) classification of hepatic hydatid cysts is used to assess the stage of hepatic hydatid cysts on ultrasound and is useful in deciding the appropriate management depending on the stage of the cyst. This classification was proposed by the WHO in 2001 and, at...
Article
20° oblique projection
20° oblique projection is a troubleshooting projection used in mammography, especially in young women and in follow-up patients.
Technique
The C-arm is turned approximately 20° for a superomedial-inferolateral oblique. With the patient's feet pointing towards the unit and her torso turned slig...
Article
22q11.2 deletion syndrome
22q11.2 deletion syndrome, also known as the DiGeorge syndrome or velocardiofacial syndrome, is a syndrome where a small portion of the chromosome 22 is lost and results in a variable but a recognisable pattern of physical and behavioral features.
Epidemiology
The estimated incidence is at ~1 ...
Article
2-hydroxyglutarate
2-hydroxyglutarate (2HG) is a metabolite that accumulates in the brains of patients with IDH1 mutated (IDH1 positive) brain tumors, particularly diffuse low-grade gliomas. Although not in widespread clinical use, it is likely that 2-hydroxyglutarate, which resonates at 2.25 ppm, will be able to ...
Article
3-6-9 rule (bowel)
The 3-6-9 rule is a simple aide-memoire describing the normal bowel caliber:
small bowel: <3 cm
large bowel: <6 cm
appendix: <6 mm
cecum: <9 cm
Above these dimensions, the bowel is generally considered dilated, and obstruction or an adynamic/paralytic ileus should be considered.
Article
3D conformal radiation therapy
3D conformal radiation therapy (3D-CRT) is a radiation therapy technique that involves CT planning where the volume to be treated is defined on a 3D data set. Therefore, organs at risk can also be delineated to shield these and reduce treatment side effects. Radiotherapy planning software is use...
Article
3D fast spin echo (MRI sequence)
3D fast spin-echo sequences are MRI pulse sequences that are able to rapidly image relatively large volumes of tissue with high resolution whilst retaining many of the advantages of fast spin-echo sequences.
They are able to create the same weightings as traditional 2D sequences (i.e., T1, T2,...
Article
3D printing
3D printing, a term often used synonymously with additive manufacturing, is a process of creating objects from three-dimensional digital information. In most cases, 3D printing is, in fact, additive manufacturing, a process in which objects are built by adding material layer by layer. This proce...
Article
3D ultrasound
Three-dimensional (3D) ultrasound is a technique that converts standard 2D grayscale ultrasound images into a volumetric dataset. The 3D image can then be reviewed retrospectively. The technique was developed for problem-solving (particularly in obstetric/gynecologic exams) and to potentially re...
Article
4D syndrome
4D syndrome is a term used to describe a manifestation of syndromic glucagonoma, a type of pancreatic endocrine tumor.
D: dermatitis 2
necrolytic migratory erythema - a widespread rash, tending to involve perioral and perigenital regions
oral rashes (angular stomatitis, cheilitis)
tend to re...
Article
5-F risk factors for cholelithiasis (mnemonic)
The 5-F rule refers to risk factors for the development of cholelithiasis in the event of upper abdominal pain:
fair: more prevalent in the Caucasian population 1
fat: BMI >30 kg/m2 and hyperlipidemia 3,4
female
fertile: one or more children
forty: age ≥40 years
cholelithiasis can occur in...
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