Normal Variants in theChest
Adam Guttentag M.D.
Albert Einstein Medical Center
Philadelphia, PA
this shouldn't last long
nipple markers
nipple shadows
subpleural fat rt
subpleural fat left
ct med 1
ct med2
ct med 3
ct med 4
Right aortic arch
Right arch close
situs inversus pa
pectus PA
pectus lat
pectus C
cervical rib
pseudarthrosis 1st rib 1
Normal
Cervical rib
Up to 8% incidence
variable size
may articulate with 1st rib
usually Asx
may cause “mass” or thoracic outletsyndrome
What if computer error messageswere in haiku form?
Windows NT crashed.
I am the Blue Screen of Death.
No one hears your screams.
cervical rib with pseudoarticulation
Cervical rib with pseudoarticulation with 1st rib
hypoplastic rt 1st rib
T1
pseudoarticulation of ribs
Bony bridging of ribs
pseudarthrosis 1st rib 1
pseudoarthrosis 1st rib 2
Pseudo-fracture of 1st rib
fused ribs pa
fused ribs lordotic
Fused ribs
rib forking
rib forking
absent  1st rib except cartilage
absent  1st rib except cartilage
1st rib absent except for cartilage
pa
pa bone
oblique bone
rhomboid fossae 1
rhomboid fossae 1
Rhomboid fossa
Attachment of costoclavicular ligamentsconnecting 1st rib to clavicle
may simulate lung disease
rhomboid fossae 2
Yesterday it worked.
Today it is not working.
Windows is like that.
Left SVC
Found in 0.4% of normal patients
>4% of patients with CHD
May be solitary (85%) or with separateright SVC
empties into right atrium via coronarysinus
differentiate from anomalous pulmonaryvein (“vertical vein”)
Left SVC CT 1
Left SVC CT 2
Left SVC CT 3
Left SVC CT 4
DSCN0104(1)
DSCN0105(1)
DSCN0106(1)
DSCN0107
Aberrant right subclavian artery
Incidence 0.5%
dilated origin known as diverticulum ofKommerell
usually asymtomatic
courses behind trachea and esophagus
aberrant RSCA CT
DSCN0004
pa
pa close 2
ct1
ct2
ct3
DSCN0019(5)
Superior Intercostal Vein
aka “aortic nipple”
left sided homologue of azygos arch
connects hemiazygos system with leftsubclavian vein
pathway of collateral flow withobstructed SVC or LBCV
Anatomy sup int vein
aortic nipple pa
aortic nipple close
pa
ct1
ct2
ct3
DSCN0009(1)
pa
lat
Anatomy sup int vein
Anatomy azygos arch
cisterna chyli
Lung cancer. ?mets
cisterna chyli netter drawing
pa
ct
Three things are certain.
Death, taxes and lost data.
Guess which has occurred.
Accessory fissures
Present in up to 50% of lungs
Vary from superficial slits to completefissures extending to hilum
May limit spread of disease process inunusual ways
Mostly of academic interest:
Recognize and ignore!
Azygos fissure
Invagination of azygosvein into RUL
Only accessory fissureto have both visceraland parietal pleura (2layers each)
Variable amount ofRUL isolated
Azygos vein visible asteardrop shapednodule at the end ofthe fissure
Inferior Accessory Fissure
Either lower lobe
More common on right
Seen to some degree in 45% at autopsy
Seen radiographically in 8%
Seen more commonly on CT - 16%
Separates medial basal segment fromthe rest of the lower lobe basalsegments
Left minor fissure
Separates lingular segments from therest of the LUL
2-8% of CXR’s
pa
pa close before
ct4
Superior Accessory Fissure
Separates superior segment fromremained of lower lobe
Found on both sides
More common on right
Accessory fissure LUL
Your file was so big
It must have been quite useful
But now it is gone.
einstein time=money