Items tagged “anatomical variant”
63 results found
Article
5th metacarpal pit
The 5th metacarpal pit refers to the normal exaggeration of the pit-like depression in the head of fifth metacarpal 1.
Differential diagnosis
It should not be mistaken for a boxer fracture (old or new) or an erosion.
Article
Azygos lobe
An azygos lobe is a normal variant that develops when a laterally displaced azygos vein creates a deep pleural fissure into the apical segment of the right upper lobe during embryological development. It is not a true accessory lobe as it does not have its own bronchus or corresponding specific ...
Article
Concha bullosa
Concha bullosa (plural: conchae bullosae) (also known as middle turbinate pneumatization) is a common finding and although associated with deviation of the nasal septum, it is usually of little clinical importance.
Epidemiology
Concha bullosa is a normal variant and is one of the most common v...
Article
Os acromiale
Os acromiale is an anatomical variant and represents an unfused accessory center of ossification of the acromion of the scapula.
Epidemiology
Os acromiale is relatively common, seen in ~8% (range 1-15%) of the population 1,2 and can be bilateral in 60% of individuals 5.
Clinical presentation
...
Case
Retroaortic left renal vein (MRI)
Published
15 May 2008
83% complete
MRI
Article
Bifid median nerve
A bifid median nerve is an uncommon anatomical variation in the forearm and has an increased association with a persistent median artery 4.
Epidemiology
It has an incidence of 9-19% 4. A persistent median artery is present in approximately half of those with a bifid median nerve 4.
Gross anat...
Case
Accessory fissure - right lower lobe
Published
24 Dec 2009
65% complete
CT
Case
Os acromiale with impingement
Published
12 Apr 2010
87% complete
MRI
X-ray
Article
Popliteal artery entrapment syndrome
Popliteal artery entrapment syndrome refers to symptomatic compression or occlusion of the popliteal artery due to a developmentally abnormal positioning of the popliteal artery in relation to its surrounding structures such as with the medial head of gastrocnemius or less commonly with popliteu...
Case
Popliteal artery entrapment syndrome
Published
15 Apr 2010
92% complete
MRI
Article
Extensor digitorum brevis manus muscle
The extensor digitorum brevis manus (EDBM) muscle is an accessory muscle in the hand and is a normal anatomical variant.
Summary
origin: distal radius and posterior radiocarpal ligament
insertion: extensor hood of 2nd or 3rd digits (variable)
innervation: posterior interosseous nerve
actio...
Case
Branchial cleft cyst
Published
07 Oct 2010
47% complete
Ultrasound
Case
Anomalous right coronary artery (ARCA) with interarterial course
Published
23 Nov 2010
92% complete
CT
Article
Anomalous pancreaticobiliary junction
Anomalous pancreaticobiliary junction, also known as pancreaticobiliary maljunction, describes the abnormal junction of the pancreatic duct and common bile duct that occurs outside the duodenal wall to form a long common channel.
Epidemiology
The incidence varies from 1.5% to 3.2% 11. The esti...
Case
Retroaortic left renal vein
Published
03 Jul 2011
77% complete
CT
Case
Cervical rib
Published
04 Jul 2011
45% complete
CT
Case
Aberrant right subclavian artery (CTA)
Published
20 Jul 2011
74% complete
CT
Case
Supernumerary toe
Published
08 Mar 2012
57% complete
X-ray
Article
Ostiomeatal complex narrowing due to anatomical variations
Some ostiomeatal complex anatomical variations, which do not cause disease by themselves, can promote narrowing and even obstruction 1:
concha bullosa ~10% (range 4-15%) - aerated middle turbinate
intralamellar cell: air cell within vertical portion of the middle turbinate
oversized ethmoid ...
Case
Fabella
Published
13 Mar 2013
82% complete
X-ray