Items tagged “variant”
425 results found
Article
Synovial plicae (knee)
Synovial plicae are folds of synovium, thought to represent embryologic remnants. They are common, present in ~90% of arthroscopies 3.
They have been implicated in anterior knee pain and possibly in chondromalacia patellae although their role remains controversial 1,3.
Gross anatomy
Some pl...
Article
Ectopic thyroid
An ectopic thyroid gland is one which is located in a location other than the normal position anterior to the laryngeal cartilages.
Terminology
Ectopic tissue refers to the tissue located outside its normal anatomical position whereas accessory tissue refers to extra tissue located remotely fr...
Article
Lunate morphology
Several classification systems exist for the lunate morphology 1, 2.
Classification
The lunate classification proposed by Viegas et al. is arguably the most relevant 3:
type I lunate: single distal articular facet for the capitate
type II lunate: additional distal articular facet medially f...
Article
Faceless kidney
A faceless kidney refers to one in which the normal appearance of the renal sinus on cross-sectional imaging is absent. It was initially described as a sign of duplication of the collecting system 1 (a slice obtained between the two collecting systems will not demonstrate the normal components o...
Case
Horseshoe kidney
Published
27 May 2010
62% complete
CT
Article
Sigmoid kidney
A sigmoid kidney is an uncommon variant of the horseshoe kidney. Whereas the typical horseshoe kidney is fused only at the lower poles, in a sigmoid kidney both the upper and the lower poles are fused 1.
Article
Supracondylar spur
A supracondylar spur, supracondylar process, supratrochlear spur, or avian spur of the distal anteromedial humeral cortex is an anatomical variant present in ~1% 1,2 of the population.
Gross anatomy
The supracondylar spur is typically located on the anteromedial humeral cortex, 5 cm proximal ...
Article
Tracheal bronchus
A tracheal bronchus (with some variations also known as a pig bronchus) is an anatomical variant where an accessory bronchus originates directly from the supracarinal trachea.
Terminology
The term (pig bronchus or bronchus suis) is often given when the entire upper lobe (usually right side) i...
Case
Atlanto-occipital assimilation
Published
08 Aug 2010
50% complete
X-ray
Article
Cavum veli interpositi
A cavum veli interpositi (CVI), often incorrectly termed a cavum velum interpositum, is an anatomic variation where there is a dilatation of the normal cistern of the velum interpositum. When larger than 1 cm in axial transverse measurement, with outwardly bowed margins and positive mass effect,...
Article
Accessory breast tissue
Accessory breast tissue, also known as polymastia, is a relatively common congenital condition in which abnormal accessory breast tissue is seen in addition to the presence of normal breast tissue. This normal variant can present as a mass anywhere along the course of the embryologic mammary str...
Case
Pancake adrenal gland in patient with a right pelvic kidney
Published
19 Oct 2010
63% complete
Ultrasound
Case
Agenesis of the dorsal pancreas
Published
20 Oct 2010
39% complete
CT
Case
Arcuate uterus
Published
20 Oct 2010
59% complete
MRI
Article
Cervical rib
Cervical ribs are supernumerary or accessory ribs arising from the seventh cervical vertebra. They occur in ~0.5% of the population, are usually bilateral, but often asymmetric 2, and are more common in females.
Related pathology
Although cervical ribs are usually asymptomatic, they are the mo...
Article
Crossed fused renal ectopia
Crossed fused renal ectopia refers to an anomaly where the kidneys are fused and located on the same side of the midline.
Epidemiology
The estimated incidence is around 1 out of 1000 births 1. There is a recognized male predilection with a 2:1 male to female ratio. More than 90% of crossed ren...
Article
Vesicourachal diverticulum
Vesicourachal diverticulum, or just urachal diverticulum, is one of the congenital urachal remnant abnormalities.
Gross anatomy
It is the proximal equivalent of a urachal umbilical sinus, representing a result of the failure of the urachus to close at the urinary bladder, forming an out-pouchi...
Article
Anomalous course of coronary arteries
Anomalous course of a coronary artery is a type of congenital coronary artery anomaly. It may represent a benign and incidental finding, but rarely it is a malignant course predisposing patients to life-threatening myocardial ischemia or arrhythmias, depending on where the artery runs.
Clinica...
Article
Butterfly vertebra
Butterfly vertebra, also sometimes known as a sagittal cleft vertebra or anterior rachischisis, is a type of vertebral anomaly that results from the failure of fusion of the lateral halves of the vertebral body because of persistent notochordal tissue between them.
Pathology
Butterfly vertebra...
Article
Azygos continuation of the inferior vena cava
Azygos continuation of the inferior vena cava (also known as the absence of the hepatic segment of the IVC with azygos continuation) is an uncommon vascular anomaly and is a cause of a dilated azygos vein.
Terminology
Spelling it "azygous" when referring to the vein is incorrect, regardless of...