Articles
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311 results found
Article
1-2-3 rule (ovary)
The 1-2-3 rule is a simple aide-mémoire describing the nomenclature of any small simple anechoic cystic appearing structure within an ovary on ultrasound:
<1 cm = follicle
1-2 cm = dominant follicle
>3 cm = cyst
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
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...
Article
Abdominal distension (mnemonic)
A mnemonic for causes of abdominal distension (6 Fs) is:
F: fat
F: fluid
F: flatus
F: feces
F: fetus
F: fulminant mass
Article
Abdominal organ echogenicity (mnemonic)
This mnemonic helps to remember the relative echogenicity of abdominal organs on ultrasound:
Darling Parents So Love Kids
Mnemonic
From most to least echogenic:
D: diaphragm
P: pancreas
S: spleen
L: liver
K: kidneys (cortex)
Article
Abdominal paracentesis contraindications (mnemonic)
A mnemonic to remember the contraindications to abdominal paracentesis is:
CAPSID
Mnemonic
C: coagulopathy (INR >2.0)
A: abdominal wall cellulitis
P: pregnancy
S: surgical abdomen (absolute contraindication) / severe thrombocytopenia (platelet count <50 x 103/μL)
I: intra-abdominal adhes...
Article
Abnormal collection of barium anywhere (mnemonic)
A mnemonic used for abnormal collection of barium anywhere in the body:
FED UP
Mnemonic
F: fistula
E: extravasation
D: diverticulum
U: ulcer
P: perforation
Article
Accessory ossicles of the wrist (mnemonic)
The accessory ossicles of the wrist can be easily recalled with the mnemonics:
LOTTEO 1
HOTELS
Mnemonics
LOTTEO
L: lunula
O: os styloideum (carpal boss)
T: (os) triangulare
T: (os) trapezium secondarium
E: (os) epilunate
O: os hamuli proprium
HOTELS
H: (os) hamuli proprium
O: os tri...
Article
Acro-osteolysis (mnemonic)
The causes of acro-osteolysis can be remembered using the mnemonic:
CHOP FINger
PINCH FO
Mnemonic
CHOP FINger
Potentially easy to remember because acro-osteolysis makes the affected phalanges look like they have been chopped off.
C: collagen vascular disease, e.g. scleroderma, Raynaud dise...
Article
Acute abdominal pain differential diagnosis (mnemonic)
A mnemonic to remember the basic differential diagnosis of acute abdominal pain is:
ABDOMINAL
Mnemonic
A: appendicitis
B: biliary tract disease
D: diverticulitis
O: ovarian disease
M: malignancy
I: intestinal obstruction
N: nephritic disorders
A: acute pancreatitis
L: liquor (ethano...
Article
Acute bacterial meningitis complications (mnemonic)
The complications of acute bacterial meningitis can be remembered using the mnemonic:
HACTIVE
Mnemonic
H: hydrocephalus
A: abscess
C: cerebritis / cranial nerve lesion
T: thrombosis
I: infarct
V: ventriculitis/vasculopathy
E: extra-axial collection: empyema and hygroma
Related articles...
Article
Acute pancreatitis severity criteria (mnemonic)
A mnemonic to remember the severity criteria for acute pancreatitis is:
PANCREAS
Mnemonic
P: PAO2 <8 kpA
A: age >55 years
N: neutrophilia (WBC >15 x 109 / L)
C: calcium <2 mmol/L
R: renal (urea >16 mmol/L)
E: enzymes (LDH >600 IU/L and AST >200 IU/L)
A: albumin (serum) <32 g/L
S: sugar...
Article
Acute stroke symptoms (mnemonic)
Useful mnemonics to remember the symptoms of acute stroke are:
FAST
BE-FAST
Mnemonics
FAST
F = face (look uneven?)
A = arm (drift down?)
S = speech (sound strange or difficulty speaking)
T = time (brain cells die every second)
BE-FAST
B = balance (sudden loss of balance)
E = eye (sudd...
Article
Adynamic ileus (mnemonic)
A mnemonic for the common causes of adynamic ileus is:
5 Ps
Mnemonic
The classic "5 Ps" are:
P: postoperative
P: peritonitis
P: potassium: low (also disturbances of other electrolytes)
P: pelvic and spinal fractures
P: parturition
However, there are a few further Ps that can be included...
Article
Aging blood on MRI (mnemonic)
Aging blood on MRI is dependent on the varying MRI signal characteristics of hemorrhagic collections with time and can be very useful in correlating the imaging findings with the clinical picture. However, as it can be complicated to recall the MRI features of aging blood through the 5 stages of...
Article
Anion gap metabolic acidosis causes (mnemonic)
A mnemonic to remember the commonest causes of anion gap metabolic acidosis is:
GOLDMARK
Mnemonic
G: glycols (ethylene glycol and propylene glycol)
O: oxoproline
L: L-lactate
D: D-lactate
M: methanol
A: aspirin
R: renal failure
K: ketoacidosis
Article
Annulus of Zinn contents (mnemonic)
A mnemonic to remember the contents of the tendinous ring (also known as the annulus of Zinn) from superior to inferior is:
One Canal, Several Orbital Nerves In One Annulus
Mnemonic:
OC: optic canal
SO: superior division of oculomotor nerve
N: nasociliary nerve
IO: inferior division of ocu...
Article
Anterior ankle tendons (mnemonic)
A mnemonic that refers to the order of the anterior ankle tendons around the ankle is:
Tom Hates Dick
The mnemonic can be used to remember the order of the tendons from medial to lateral as they pass under the extensor retinaculum of the ankle.
Mnemonic
T: tibialis anterior
H: extensor hal...
Article
Anterosuperior mediastinal mass (mnemonic)
The common causes of an anterosuperior mediastinal mass can be remembered by using the mnemonic:
5 Ts
Mnemonic
T: thymus
T: thyroid
T: thoracic aorta
T: terrible lymphoma
T: teratoma and germ cell tumors - see mediastinal germ cell tumors
Testicular cancer metastasis can represent a sixt...
Article
Aortic arch branches (mnemonic)
A useful mnemonic to remember the major branches of the aortic arch is:
ABC'S
Mnemonic
A: arch of aorta
B: brachiocephalic trunk
C: left common carotid artery
S: left subclavian artery
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