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Animal and animal produce inspired signs

Dr MT Niknejad and Dr Frank Gaillard et al.

Animal and animal produce inspired signs may sound a little silly, but in my defence I didn't make these up. The radiology literature is replete with signs, some more fanciful than others.

Fish and seafood

fish vertebra (also known as codfish vertebra) : biconcave vertebrae as seen in osteoporosis
fishtail deformity of the elbow : due to abnormal trochlear ossification following a distal humeral fracture in childhood
vertebral scalloping : may be anterior or posterior border
endosteal scalloping : medullary cavity masses, e.g multiple myeloma
lobster claw sign: of papillary necrosis

Poultry and fowl

eggshell calcification : silicosis and occasionally sarcoidosis
swan neck deformity : of rheumatoid arthritis
bird-beak sign : achalasia (also known as rat tail sign)
beak sign : of arterial dissection
beak sign of sigmoid volvulus
gull wing appearance: erosive osteoarthritis

Domesticated and wild animals

bull's eye : many of these
staghorn calculus : struvite renal calculi
feline oesophagus : horizontal striations seen on barium swallows as a variant of normal.
eye of tiger sign: classical of Hallervorden-Spatz syndrome
pleural mouse
panda sign
- of the midbrain : Wilson disease
- of sarcoidosis
bear's paw sign : xanthogranulomatous pyelonephritis
scotty dog sign
hidebound sign : gastrointestinal scleroderma
dural tail : of meningioma - don't know tail of which animal though
rat tail sign : achalasia (also known as bird-beak sign)
rat bite erosions of gout
bat's wing: pulmonary opacities and 4th ventricle (Joubert anomaly and related syndromes)
anteater nose sign: calcaneonavicular coalition

Insects and bugs

butterfly glioma : nothing "oooh... isn't it pretty" about this one
butterfly shape of the grey matter of the spinal cord
butterfly fracture

Reptiles

cobra head sign : of ureterocoele

Mythical creatures

cyclops lesion : usually post ACL repair
medusa head : of a developmental venous anomaly (DVA)

Processed animal product containing foods

cervical hamburger sign : normal cervical facet joints on axial CT
honeycomb lung : UIP / pulmonary fibrosis
mesenteric hamburger sign : mesenteric lymph node enlargement
omental cake : metastases to omentum - I don't think anyone actually makes cake out of omentum.
sausage digit : underlying inflammatory arthritis or dactylitis
head cheese sign : hypersensitivity pneumonitis
leather bottle stomach : of linitis plastica (aka water bottle sign)