Differential Diagnosis Flashcards
Nephrocalcinosis differential
Medullary sponge kidney
Renal tubular acidosis
HyperParathyroidism
TB - end stage (putty kidney)
Sacral tumours
Chordoma
Plasmacytoma
Diffusely sclerotic bone thickened trabecular markings
Paget’s
Fibrous dysplasia
SAPHO - hyperostosis
Thalassaemia
Lytic bone mets?
Renal
Lung
Thyroid
Melanoma
Breast
Differential for AVN in adults
Diabetes
Steroids
Sickle cell
Miliary nodules?
TB
Varicella
Sarcoidosis
Thyroid
Ovarian
Renal
Cavitating lung lesions
Infection:
Septic emboli, TB, Klebsiella,
Aspergillosis
Malignancy:
Squamous lung ca
Vascular:
Granulomatosis with polyangitis
LCH
Distal ureteric stricture
Tb
Schistosomiasis
Congenital mega ureter
Congenital multi cystic mass on CXR
CPAM - Can have connection to bronchial tree
Bronchogenic cyst - No communication with the bronchial tree
Pleuropulmonary blastoma - malignant
Cerebral processes involving at least two lobes of the brain
Gliomatosis cerebri
Lymphoma
Encephalitis
Interstitial lung disease and soft tissue calcification?
Scleroderma
Dermatomyositis
Multifocal splenic lesions
TB
Sarcoidosis
Lymphoma
Siderosis (sickle cell)
Differential for demyelinating lesions in the brain?
Multiple Sclerosis
ADEM - post infection
Progressive multifocal leukoencephalopathy - fronal and parietal lobes, AIDS related.
Differential for eggshell calcification mediastinal lymph nodes?
Pneumoconiosis
Silicosis
Sarcoidosis
TB - ranke complex (healed primary TB)
Differential for neonatal hyperinflated lung
Congenital lobar hyperinflation - associated with aberrant left pulmonary artery
Bronchial atresia - distal air trapping
Swyer James - post infective obliterative bronchiolitis
Pulmonary hypoplasia - contralateral lung smaller or missing
Signs to look for to help you find a primary lesion if you find metastases?
Mastectomy
Surgical clips
Post radiation changes
Nephrectomy
Differential for neonatal large multi cystic liver masses
Infantile hepatic hemangioma - benign, solid, normal AFP, often no treatment required
Mesenchymal hamartoma - benign, cystic, normal AFP, surgical resection
Hepatoblastoma - malignant, raised AFP, surgical resection +/- chemo
Hepatic abscess
Neuroblastoma Vs Wilms?
Neuroblastoma
- Poorly marginated
- Calcification
- Bone metastasis
- Encases vessels
- Spinal canal extension
Wilms
- Well circumscribed
- No calc
- Lung metastasis
- Displaces vessels
Differential for white out?
Dense consolidation
Pleural effusion
Pneumonectomy
Combination of all
Differential for enlarged pulmonary arteries
COPD
CTEPH
Chronic left heart failure
Becet disease
Massive mediastinal lymph nodes compared to the size of the lung cancer. Diagnosis?
Small cell lung cancer
Most common mets to bowel?
Melanoma
Breast
Differential for necrotic lymph nodes?
TB
Lymphoma
Squamous cell cancer
What are 5 types of choledochal cysts?
1 - focal dilatation of the CBD
2 - bile duct diverticulum
3 - dilation of CBD within the duodenal wall (choledochocele)
4 - focal intra and extra hepatic dilatation
5 - Carolis disease (intrahepatic only)
Differences between metabolic and metastatic superscan
Metastatic - axial skeleton and proximal limbs. More heterogeneous
Metabolic - axial skeleton, distal limbs, calvarium and mandible
Causes of metabolic superscan?
Hyperparathyroidism
Renal osteodystrophy
Osteopetrosis
Differential for soft tissue calcification?
Autoimmune - scleroderma, dermatomyositis
Trauma - myositis ossificans
Vascular - arterial calcification
Metabolic - CPPD
Malignancy - osteosarcoma
Fat containing renal lesions
AML
RCC
Oncocytoma
Wilms (Paeds)
What is Ying Yang sign mean for arterial Doppler?
Aneurysm
Sharp systolic upstroke as blood enters the aneurysm. Then sharp reversal of flow as blood leaves the aneurysm.
Difference between inguinal, femoral, and obturator hernia?
Inguinal Vs femoral - femoral remains lateral to the pubic tubercle and compresses the femoral vein
Obturator hernia goes through obturator canal
Differential for multiple testicular lesions?
Lymphoma
Sarcoidosis
Multifocal seminoma
Mets - prostate, penile
What shows uptake on ocreotide or gallium DOTATATE scan?
Neuroendocrine tumours:
- Carcinoid
- Paraganglioma
- Phaeochromocytoma
- Small cell lung cancer
Scan to look for Meckel’s diverticulum?
Tc99m Pertecnitate scan
What are the abnormal oesophageal indentations?
Anterior - aberrant left pulmonary artery
Posterior - aberrant right subclavian artery
Diagnostic measurements for pyloric stenosis?
Pyloric length - >15mm
Transverse diameter - >12mm
Pyloric thickness - >3mm
Differential for double bubble sign on abdo film?
Duodenal web / atresia / stenosis,
Annular pancreas
Midgut volvulus
RDS Vs TTN Vs Meconium aspiration on neonatal CXR?
RDS - pre term, bilateral ground glass opacities, reduced lung volume
TTN - coarse interstitial marking, fluid in horizontal fissure. Resolves in 48hrs
Meconium aspiration - term, asymmetric “ropy” densities”, increased lung volume
Duplex kidney pattern of insertion and pathology?
Upper pole insert lower and obstructs + ureterocele
Lower pole inserts higher and refluxes
Graf method for assement of DDH?
Grade 1 - Alpha angle >60⁰ (normal)
Grade 2 - Alpha angle <60, centered hip
Grade 3+4 - Alpha angle <60, decentered hip
Differential for lung mass with separate systemic arterial supply
AVM
Pulmonary sequestration
Differential for calcification on cranial USS?
Toxoplasmosis - random distribution
Cytomegalovirus - periventricular distribution
Things to look for if you suspect NF1
SNAP
Skeletal displasias - look at bones
Neurofibromas - look at spine and soft tissues
Astrocytomas + optic tract gliomas- MR brain
Pheochromocytoma - MR Adrenal
Differential for cerebral calcification?
Vascular - AVM, Amyloid, Sturge Weber.
Infection - TORCH
Trauma - healed infarct, bleed or abscess
Tumour - meningioma, oligodendroglioma
Causes of colonic intussusception in adults?
Lipoma
Colorectal carcinoma
Polyps
Causes of intussusception in a child?
Peyers patches (lymph tissue)
Duplication cyst
Meckel diverticulum
Upper lobe pulmonary fibrosis differential?
TB/ MAC
Sarcoid
Pneumoconiosis/silicosis (progressive massive fibrosis
Chronic hypersensitivity pneumonitis
Cardiac uptake on bone scan?
Cardiac amyloid
Causes of hook like osteophytes
Haemochromotosis
CPPD
Appearance of appendiceal pseudomyxoma peritonei
Tubular appendix with curvilinear calc
Loculated low attenuation fluid
Scalloped visceral surfaces
Causes of pseudodiverticulosis of the oesophagus?
Reflux, candidiasis.
Cause strictures in 90% of cases
Posterior mediastinal massess?
Neural tumours:
- Schwannoma
- Neurofibroma
Non-neural tumours
- Osteosarcoma
- Lymphoma
- Oesophageal tumour/duplication cyst
Infection - Paraspinal abscess
Extramedullay haematopoesis
Causes of ribbon ribs?
NF1
Osteogenesis imperfecta
Causes of acro-osteolysis
Scleroderma
Psoriatic arthritis
Raynauds
Causes of pneumocephalus?
Trauma
Iatrogenic
Meningitis - sinusitis/mastoiditis
Middle mediastinal mass differential?
Lymphadenopathy
Pericardial cyst
Cardiac/aortic aneurysm
Causes of small bowel strictures?
Crohns
TB
Ischaemia
Radiotherapy
Causes of bilateral pneumothoraces?
Cystic lung diseases
- LAM/LCH
- TB, Klebsiella, Staph aureus
- PCP pneumonia
Osteosarcoma mets
Cystic lung disease differential?
LAM - female, thin walled cysts, tuberous sclerosis
LIP - lower lobe predominant, sjogrens,
LCH - bizarre cysts, nodules, smoker
Birt Hogg Dube - lung cysts, rcc, skin lesions
PCP - ground glass and small cysts (pneumatoceles), AIDS, no pleural effusions
Diffuse muscle oedema differential?
Polymyositis
Dermatomyositis (if skin involvement)
Pyomyositis if infective
Differential for bladder diverticulosis?
Bladder outflow obstruction
Neurogenic bladder
Posterior urethral valves
Management of tuberous sclerosis?
MDT approach with regular follow up with
MRI brain (tubors, SEGA, malformation of chiari),
MRI kidneys (AML, oncocytoma)
Echocardiogram (Rhabdomyoma)
Management of osteoid osteoma?
Can do further imaging with CT or bone scan.
Radio frequency ablation.
Centrilobular ground glass nodules differential?
- Hypersensitivity pneumonitis
- RB-ILD (smokers)
- TB, Aspergillosis
Causes of PRES?
Severe hypertension
Drugs
Thrombotic thrombocytopenic purpura
Fleeting pulmonary opacities differential?
COP - Atoll sign
ABPA - asthma, finger in glove
Eosinophilic pneumonia - reverse bat wing sign.
Clival masses differential?
Chordoma - high T2
Chondrosarcoma - high T2 and calc
Plasmacytoma - low/intermediate T2
Features of chiari 2 malformation?
Low lying cerebellar tonsils and torcular
Thinned corpus callosum
Tectal beaking
Myelomeningocele (spina bifida)
Corpus callosum lesions?
Tumours:
- Butterfly glioma
- Gliomatosis cerebri
- Lymphoma
Demyelination:
- MS
- NMO
- Machiafava Bignami
Congenital
- Agenesis of the corpus callosum
High FLAIR signal in lentiform nucleus differential?
Carbon monoxide poisoning - Globus pallidus (inner strip)
Methanol poisoning - Putamen (outer strip)
Wilsons disease, Huntington’s disease - Lentiform and caudate
Ring enhancing lesions MRI brain differential?
Abscess - thin wall, lots of oedema
Tumour (mets, glioblastoma, lymphoma) - thick wall
Tumourfactive demyelination (MS, ADEM) - incomplete wall, little oedema
Glioblastomas and intestinal polyps?
Turcot syndrome
Cortical based neuro tumours differential?
P-DOG
Pleomorphic xanthoastrocytoma - supratentorial cyst with enhancing nodule
DNET - bright and bubble, do not enhance
Oligodendroglioma - cortical expansion, ribbon calc
Ganglioglioma - temporal lobe, teenagers, seizures, mixed solid cystic.
Intraventricular tumours?
MESS-C
Medulloblastoma - 4th vent roof, spinal mets
Ependtymoma - 4th vent floor, bleeds+calc
Subependymoma - subependymal, adults
SEGA - subependymal, kids, tuberous sclerosis
Central neurocytoma - swiss cheese, calc
CP angle massess differential?
Vestibular scwannoma - NF2
Meningioma - dural tail
Epidermoid - avid restriction
Dermoid - contain fat
Pineal lesion differential?
GPPP
Germinoma - fat and calc
Pineoblastoma - Heterogenous, “exploded” calc, hydrocephalus
Pineocyteoma - homogenous
Pineal cyst
Common brain mets?
Lung
Renal
Breast
Suprasella lesions?
SATCHMOE
S - sarcoid
A - aneurysm
T - teratoma, TB
C - chordoma, craniopharyngioma, cleft cyst (rathke)
H - hypothalamic hamartoma/glioma
M - meningioma, metastases, myeloma
O - optic nerve glioma
E - Eosinphilic granuloma, epidermoid/dermoid
Aging blood on MRI
T1 signal only becomes high after a couple days
T2 signal only becomes high after a week
What are the intradural but extramedullary tumours?
No more spinal masses
Neurofibroma
Meningioma
Schwannoma
Metastases
Amyloid vs hypertensive micro haemorrhage?
Hypertensive micro-haemorrhage typically affects the basal ganglia.
Amyloid micro-haemorrhage spares the basal ganglia
Spinal ependymoma vs astrocytoma?
Ependymoma - centrally within cord, haemorrhage, adults, NF2
Astrocytoma - eccentric within cord, kids, NF1
Lung cancer staging?
T1 - 1-3cm
T2 - 3-5cm, trachea or pleura
T3 - 5-7cm, chest wall, pericardium
T4 - >7cm, carina, mediastinum, oesophagus, vessels, diaphragm, vertebra.
N0
N1- ipsilateral hilar
N2 - ipsilateral mediastinal
N3 - contralateral nodes
M0
M1a - tumour in contralateral lobe
M1b - single extrathoracic met
M1c - multiple extrathoracic mets
Features of malignant mesothelioma?
Pleural thickening extending to medial pleura
Fissural extension
Pleural thickeness >1cm
Anterior mediastinal masses?
TTTT
Terrible lymphoma
Thyroid
Thymoma - myasthenia gravis
Teratoma - fat containing
Congenital heart diseases CXR appearances?
Transposition - Egg on string
Tetralogy - Boot shaped heart
TAPVR - Snowman heart
Epstein anomaly - Box heart.
Modified PIOPED criteria for VQ scan?
High probability - Two or more large (>75% of segment) segmental defects
Low probability - Upto 3 small (<25% segment) subsegmenal defects
Intermediate - anything inbetween
What is Caplan syndrome?
RA and pneumoconiosis.
Groundglass opacification differential?
Acute:
- Viral infection, (PCP, HSV, CMV, peribronchovascular)
- Hypersensitivity pneumonitis (centrilobular gg nodules)
- ARDS, dependant gradient
- Goodpastures, ground glass to crazy paving
Chronic:
- ILD, (NSIP, UIP, RB-ILD)
Bronchiectasis differential?
Upper lobe:
- CF - upper lobe
- ABPA - asthma, finger in glove
- Mycobacterium avium complex - upper lobe, cavitating lesions
- Fibrosis - radiation, pneumoconiosis, chronic hypersensitivity
Lower lobe:
- Primary ciliary dyskinesia - lower lobe
What is this condition?
Bronchiectasis
Situs invertus
Sinusitis
Kartageners syndrome
Eisenmenger syndrome?
Uncorrected left to right shunt.
Chronic pulmonary hypertension.
Pressure reveral to right to left.
True vs false cardiac aneurysms?
True - broad neck, mural thrombus
False - rupture of myocardium but containd by pericardium.
Reverse batwing appearance differential?
Peripheral opacities sparing the perihilar region.
- Chronic eosinophilic pneumonia.
- Eosinophilic polyangitis
- COVID pneumonitis
- PCP pneumonia
- Organising pneumonia.
BTS solid nodule follow up guidelines?
> 5mm - discharge.
5-6mm - 12 month CT
6-8mm - 3 month CT
> 8mm
- low risk - 12 month CT
- high risk - PET CT
Rib notching differential?
Superior:
- Osteogenesis imperfecta
- Connective tissue (Marfan, scleroderma)
Inferior:
- Coarctation of aorta
- Neurofibroma
- Schwannoma
Both (Ribbon ribs)
- NF1
Most common metastases to oesophagus?
Bronchial - local
Breast - distant
Narrow tubular stomach differential?
Atrophic gastritis
Linitis plasica - nodular
What are the radiological features of haemochromatosis?
Hepatomegaly (90%)
CT - Increased liver density.
MR - Low liver signal on T2
Hook like osteophytes 2nd+3rd metacarpals. Chondrocalcinosis.
Restrictive cardiomyopathy
Associations with Sjogrens disease?
NSIP
LIP
Primary biliary cholangitis
Bilateral parotid cysts
Appearance of thalassaemia?
ThalaSSSSaemia
Skull:
- Skull hair on end appearance
- Sinus hypopneumatisation
Spine:
- Scoliosis
- Expansion of ribs, with rib within a rib appearance
Spleen:
- Splenomegaly
Classification of renal trauma?
AAST kidney score
Grade 1 - subcapsular haematoma without laceration
Grade 2 - superficial laceration <1cm, perirenal haematoma
Grade 3 - laceration >1cm, vascular injury/active bleeding
Grade 4 - laceration involving the collecting system
Grade 5 - shattered kidney
Classification of liver trauma?
AAST liver score
Grade 1 - <1cm
Grade 2 - 1-3cm
Grade 3 - >3cm, contained active bleed
Grade 4 - 25-75% of a lobe, bleed into peritoneum
Grade 5 - >75% of a lobe
Scimitar syndrome?
PAPVR
+
Pulmonary hypoplasia
Best imaging for carcinoid tumours?
Gallium DOTATATE PET
Large vessel vasculitides?
Giant cell arteritis - older than 50
Takayasu arteritis - younger than 50
Becets disease - aorta, SVC, pulmonary artery aneurysms
Medium vessel vasculitides?
Polyarteritis nodosa
Granulomatosis with polyangitis
Eosinophilic granulomatosis
What is RBC scan used to image?
GI bleeding
Splenosis
How are parathyroid adenomas imaged?
Tc99m Sestamibi - delayed phase
4d CT
What is PI-RADS score?
Use T2 to look at transitional zone.
Uncapsulated intermediate T2 signal is bad
Score can be upgraded with DWI
Use DWI to look at peripheral zone.
Avid restriction is bad.
Score can be upgraded with dynamic contrast enancment.
Dynamic contrast enhancment.
Enhancment earlier than normal prostate is bad.
Differntial for sacroiliitis?
Bilateral symettrical:
- Ank spond
- UC/Crohns
- Rheumatoid
Bilateral asymettrical:
- Psoriatic
- Osteoarthritis
Unilateral:
- Septic arthritis
Carney triad?
Extra adrenal phaeochromocytoma
GIST
Pulmonary chondroma
Common oesophageal pathology appearances?
Barretts - reticular mucosal pattern, caused by reflux
Pseudodiverticulosis - tiny outpouching and stricture, caused by reflux
Herpes oesophagitis - small ulcers with halo of oedema
Candidiasis - discrete plaques
Glycogenic acanthosis looks similar
Types of gastric volvulus
Organoaxial - gastric antrum lies below the fundus as normal. Twisted on the axis of the stomach.
Mesenteroaxial - Gastric antrum is at the level of the fundus. Stomach twists in half along the perpendicular axis.
Terminal ileitis differential?
Typhylitis - neutropaenic colitis
Inflammatory bowel disease - Crohns
Infectious - C.Diff, TB.
Ishaemic
Malingnacy - adenocarcinoma, lymphoma
Difference between FNH and Fibrolamellar HCC?
FNH scar is T2 bright and enhances.
Fibrolamellar HCC scar is T2 dark and does not enhance
How can you assess difference between FNH and Adenoma?
FNH - centrifugal enhancement (inside out)
Adenoma - centripetal fill in (outside in)
Primovist - delayed phase.
FNH - mild enhancement compared to background liver.
Adenoma - hypointense to background liver
Metastases do not uptake Primovist
Imaging findings for cholangiocarcinoma?
Capsular retraction.
Dilated billiary ducts.
Delayed persistent enhancement.
What is pseudocirrhosis of liver?
Treated breat cancer mets to the liver
Primary biliary cholangitis imaging findings?
Lace like pattern of fibrosis
Periportal halo sign
Intrahepatic duct dilatation
Increased risk of HCC
Different types of pancreatic lesions?
Ductal adenocarcinoma - head of pancreas, blocks pancreatic duct
Serous cystadenoma - grandmother lesion, head of pancreas, bunch of grapes with central calc
Mucinous cystadenoma - mother lesion, body and tail of pancreas, uni/multi locular cyst peripheral calc
Solid pseudopapilliry tumour of pancreas - Daughter lesion, tail of pancreas, mixed solid cystic.
IPMN - main brain and side branch
What are the polyposis syndroms?
Familial adenomatous polyposis syndromes:
- Turcot - GI polyps + CNS tumours
- Gardners - GI polyps + Osteomas
Cowdens - GI polyps + Breast cancer
Peutz Jeghers - GI polyps + seminoma/adenoma malignum, skin pigmentation of fingers and toes
Juvenile polyposis - <20y.o, rectal bleeding, intusseception.
GI bleeding differential?
Vascular - AVM, angiodysplasia
Enterocolitis - infective, diverticulisis, UC, Crohns
Tumour - adenocarcinoma
Peptic ulcer disease
Meckels diverticulum
Benign causes of pneumatosis?
PSI
Pulmonary disease
Scelroderma
Inflammation
Pancreatic calcification differential?
Chronic pancreatitis
Pancreatic neoplasms - cystadenomas
Hyperparathyroidism
Hereditary pancreatitis
Stages of renal TB?
Early - papillary necrosis
Progressive - strictures and hydronephrosis
Late - thinned cortex, dystrophic calc (Putty kidney)
Diffuse oesophageal dilatation differential?
Upper
- stricture
- malignancy
- achalasia
Lower
- sclerodema, distal two thirds
Difference between omphalocele and gastroschisis?
Omphalocele surrounded by membrane Omphalocele can contain other organs
Gastroschisis is on the right of midline, only bowel
How do you assess haemngioma on multiphase contrast imaging?
Peripheral nodular discontinuous ehnancment with progressive centripetal fill in.
Matches the blood pool.
Hypervascular liver lesions?
Benign
- FNH
- Adenoma
- Haemangioma
Malignant
- HCC
- Mets
Hypo-vascular liver lesions?
Cyst
Cholangiocarcinoma - delayed phase enhancment due to fibous tissue
T2 dark renal lesions?
- Lipid poor AML
- Haemorrhagic cyst
- Papillary RCC
Bladder calc differential?
Chronic cystitis
Schistosomiasis
TB
Radiation
Difference between utricle cyst or mullerian duct cyst on urethrogram?
Mullerian duct cyst can extend above the prostate
Utricle cyst does not extend above the prostate.
How do you differentiate AD-PKD Vs AR-PKD?
AD - round cysts distributed throughout the kidneys, occurs in adults
AR - tubular cysts sparing the cortex, occurs in kids
Posterior vertebral scalloping differential?
Intra dural spinal masses - neurofibromatosis, ependymoma, astrocytoma
Dural ectasia - Marfan’s disease, ehlers danlos
Congenital - achondroplasia, osteogenesis imperfecta
Name some causes of anterior vertebral scalloping?
AAA
Lymphoma
Downs syndrome
Causes of Chondrocalcinosis?
C,C,Cs
Crystals - gout, pseuodogout (COPD)
Cation - calcium, copper, iron
Cartilage degeneration - OA
Haemarthrosis differential?
Vitamin C deficiency
Trauma
Haemophylia
Tenosinvial giant cell tumour
Paediatric femoral head irregularity differential?
Juvenile Idiopathic artheritis
Perthes disease
Infection
Osteoid osteomas are considered osteoblastomas when over what size?
> 2cm
Segond fracture vs arcuate sign?
Segond - Lateral tibeal plateau #, ACL rupture
Arcuate - Proximal fibular head #, PCL tear
Subacute combined degeneration of the cord differential?
Vit b12 dificiency
Demyelination - MS
Infection - Herpes myelitis
Inflammatory - sarcoid
DISI vs VISI?
DISI - lunate tilts dorsally, increased scapholunate angle
VISI - lunate tilts volar, decreased scapholunate angle
What is a perilunate dislocation and what is it associated with?
Associated with scaphoid fractures
What are the associated injuries for positive and negative ulnar variance?
Positive - Lunate degeneration (Ulnar impaction syndrome)
Negative - Lunate AVN (Kienbock disease)
What is a Barton fracture Vs reverse Barton
Intra articular fracture of the distal radius extending to the dorsal surface. With dorsal radial carpal dislocation.
Reverse Barton is to the volar surface.
Different C Spine fractures?
Clayshoverlers - hyperextention, fracture of spinous process
Chance - hyperflexion, anterior wedge # and fracture of posterior elements. Highly unstable
Jefferson fracture - C1 blowout, axial loading
Hangmans - Bilateral pars C2 #
What is Gamekeepers thumb?
Chronic avulsion fracture of the ulnar collateral ligament of the 1st MCP joint
Acute avulsion fracture is skiiers thumb.
Creates a Stener lesion if the adductor polisis muscle gets caught in the torn UCL.
Monteggia vs Galeazzi fracture?
GRUesome MURder
G: Galeazzi R: radius fracture U: ulna dislocation
M: Monteggia U: ulna fracture R: radial head dislocation
SALTER Harris fractures?
1 - Straight through physis
2 - Above (metaphyseal)
3 - Below (epiphyseal)
4 - Through (both metaphysis and epiphysis.
5 - Rammed
Name the attachments:
Illiac crest
ASIS
AIIS
Greater trochanter
Lesser trochanter
Ischial tuberosity
Pubic symphysis
Illiac crest - abdominal muscles
ASIS - Sartorius
AIIS - Rectus femoris
Greater trochanter - Gluteal muscles
Lesser trochanter - Illiopsoas
Ischial tuberosity - Hamstrings
Pubic symphysis - ADDuctors
What is a Masonneuve fracture?
Widened medial malleolus/medical malleolus fracture + proximal fibular fracture.
What other injury is associated with bilateral calcaneal fractures?
Bilateral”Lover’s fractures” should prompt looking at the spine for burst fractures
Gibbous deformity differential?
Congenital:
- Achondroplasia
- Mucopolysaccharides
Aquired:
- Trauma
- Infection - pyogenic discitis, TB
Vertebra planar differential?
Trauma
LCH
Mets, myeloma, lymphoma
Osteomyelitis
What are the different bone lesions that can have multiple fluid-fluid levels?
Telangiectatic osteosarcoma
Aneurysmal bone cyst
Giant cell tumour
How to differentiate Osteosarcoma from Ewing’s Sarcoma?
Ewing’s:
- Diaphysis femur
- Rarely calcifies
- Onion skin periosteal reaction
- Mets to bones and lung
Osteosarcoma:
- Metaphysis distal femur
- Amorphous calcification
- Sun burst periosteal reaction
- Mets to bones and lung with pneumothorax
How to differentiate enchondroma from chondrosarcoma?
Chondrosarcoma:
Cause pain,
Cortical destruction/scalloping,
Typically >5cm in size.
What are the epiphyseal lesions?
CGI
Chondroblastoma - T2 low, <30yo
GCT - >30
Geode - degenerative disease
Infection - brodies abscess crosses physis
What are the lucent bone lesions?
F - Fibrous dysplasia
E - Enchondroma, eosinophilic granuloma
G - GCT
N - NOF
O - Osteoblastoma
M - Myeloma, metastases
A - ABC
S - Solitary bone cyst
H - Hyperparathyroidism
I - Infection
C - Chondroblastoma
Polyostotic fibrous dysplasia syndromes?
MC Cune Albright - also gets Cafe au lait spots and precocious puberty
Mazabraud - also gets soft tissue myxomas
What is the difference between Olliers and Maffucci syndrome?
Both are multiple Enchondromas
Maffucci also have haemangiomas and increased risk of chondrosarcoma
What is Undifferentiated Pleomorphic Sarcoma?
Malignant transformation of benign tumours
Pagets disease, fibrous dysplasia, GCT, enchondroma
Classic imaging findings of Synovial sarcoma?
Young people
Periphal limb (Knee/foot)
T2 “triple sign” - necrosis, soft tissue, calc
Bowl of grapes - blood, fluid fluid levels
What are the differences between RA and Psoriatic arthritis?
RA - symmetric, proximal (MCP), osteoporosis instead of bone proliferation.
PA - Asymettric, distal (IPJs), boneproliferation instead of osteoporosis (periostitis), enthesitis.
Classic imaging features of skeletal sarcoidosis?
Lace like honeycomb destruction of phalanges. Preservation of joint space
Lytic lesions in the skull and spine. Preservation of disc spaces
Classic imaging features of Rickets?
Fraying and cupping of the metaphyses.
Bowed legs with looser zones - pseudofracture of the compression side.
Primary myelofibrosis imaging findings?
Extramedullary haematopoesis
Splenomegally
Diffuse sclerotic bone
Diffuse sclerotic bone differential?
Osteopetrosis
Hyperparathyroidism/Renal osteodystrophy
Mets, myelofibrosis, mastocytosis
Rugger jersey spine differential?
Pagets disease
Osteopetrosis
Hyperparathyroidsm/renal osteodistrophy
Most common patella tumour?
Giant Cell Tumour >30yo
Chondroblastoma <30yo
Typical imaging features of a chondroblastoma?
Epiphyseal
Lucent
Narrow zone of transition
Cloud like with rings and arcs
T2 LOW - The only epiphyseal lesion that is NOT high T2 signal
Features of acromegally?
Skull and spine:
- Calvareal thickening
- Vertebral body fractures without loss of mineral density
Hand and feet:
- Spade like phalanx
- Heel pad thickness >25mm
Secondary complications of Pagets disease?
Conductive hearing loss - otosclerosis
Hydrocephalus - basilar invagination
Osteosarcoma - 1% of patients
Features of Rheumatoid Arthritis?
Hands, elbows, shoulder
Hands:
- marginal erosion MCP joints
- juxta-articular osteoporosis
Elbows/knees:
- Joint effusion
Shoulder:
- Erosion of distal clavicle
How do you differentiate between Morquio and Hurler syndrome?
Both are mucopolysaccharidoses (lysosomal storage disorder).
Both have platyspondyly.
Morquio has anterior CENTRAL vertebral body beaking.
Hurler has anterior INFERIOR vertebral body beaking.
Remember H comes before I (Hurler Inferior).
Types of tenosynovial giant cell tumour and most common joints affected.
Diffuse - knee joint most affected
Localised - fingers most affected
Dermatomyositis appearance and associations?
Sheet like calcification in soft tissues
Associated with interstial lung disease and generalised increase risk of malignancy
Different subtypes of femoro acetabular impingement syndrome?
Cam type - anterior superior bump on femoral neck causing impingement
Pincer type - over coverage of the femoral head by the acetabulum causing impingement. (Coxa profunda, or protrusion acetabulum are potential causes)
How can you differentiate coxa profunda and protrusio acetabuli?
Protrusio acetabuli - the femoral head projects beyond the ilioischial line (i.e. into the pelvis)
Unilateral testicular lesions differential?
Seminoma
Epidermoid - onion skin
Abscess
Adrenal rests
Metastases - retroperitoneal
Bilateral testicular lesions differential?
Lymphoma
TB
Sarcoidosis - testicular and epididymal masses
Multifocal seminoma
Ovarian mass, ascites, pleural effusion differential?
Meigs syndrome - Ovarian fibroma, Ascites, Pleural effusion.
Ovarian hyperstimulation syndrome - Theca lutein cysts, ascites, pleural effusion
What is Salpingitis Ithmica Nodosa (SIN)
Nodular scarring of the fallopian tube. Basically it’s diverticulosis of the fallopian tubes secondary to inflammation/infection.
High association with infertility and ectopic pregnancy
What is Ashermans syndrome?
Intrauterine adhesions.
Secondary to prior surgery, infection, or pregnancy.
Clinically can result in infertility.
Classic imaging features of adenomyosis?
Thickening of the junctional zone >12mm
Can have high T2 signal in junctional zone or myometrium (cystic change)
How does endometrial cancer typically enhance?
Typically enhances less than the myometrium
Hyperechoic endometrial lesions?
Endometrial polyp -Single feeding vessel on Doppler
Blood clot
Retained prodeuct of pregnancy
What are the simple ovarian cyst follow up criteria?
Pre menopausal:
<3cm - normal
3-5cm - report presence, no follow up
>5cm - follow up in 3-12 months based on suspicion
Postmenopausal:
<1cm - normal
1-3cm - report presence, no follow up
>3cm - follow up in 3-12 months based on suspicion
Ovarian cystic mass differential?
Haemorrhagic cyst - lace like, no flow
Endometrioma - ground glass cyst
Teratoma - cyst with nodule (rokitansky)
Ovarian serous/mucinous tumours
Seminoma vs non seminoma USS findings
Seminoma - Hypoechoic, homogenous, microcalc
Non seminoma - Heterogenous with cystic spaces and calc (teratoma is differential)
Testicula tumours hormone markers?
bHG - Seminoma, Choriocarcinoma
AFP - Mixed germ cell, Yolk sac
Fibroid vs leiomyosarcoma MRI?
Fibroid- T1 + T2 dark, homogenous enhancment
Leimyosarcoma - same, but with central necrosis
Normal endometrial thickness in postmenopausal women vs tamoxifen thickness?
<4-5mm
Tamoxifen - 12mm
Cervical cancer staging, most important part?
FIGO staging
2a spread beyond the cervix, NO parametrial invasion - Surgery
2b spread beyond the cervix, WITH parametrial involvement - Chemo radiotherapy
Ring of fire ovarian lesion differential?
Ectopic - thick echogenic rim, ring of fire, separate from ovary
Corpus luteum - thin echogenic rim, ring of fire, moves with ovary
What are the causes of hydrosalpinx?
PID
Endometriosis
Torsion
Tubal cancer
Post hysterectomy
What is a peritoneal inclusion cyst?
Occurs when adhesions envelope an ovary.
Adhesions cannot absorb the normal secretions of the ovary and so they collect and form a cyst.
Risk factors include:
PID
Endometriosis
Surgery
What day of the hormone cycle is MRI and Mammography best performed?
Follicular phase - day 7-14
Benign vs malginant mammogram calcification?
Benign - popcorn (fibroadenoma), vascular, egg shell (oil cyst)
Malignant - pleomorphic, linear calc (DCIS)
Linear calc mammogram differenatial?
DCIS
Plasmacell mastitis
Indications for breast MRI?
Intralobular carcinoma - can be bilateral, difficult to see on mamogram
DCIS - see extent of disease
Renal artery aneurysm differential?
Fibromuscular dysplasia
Polyarteritis nodosa
Marfans, ehlers danlos
Classic triad of organ involvement for Granulomatosis with polyangitis?
Sinuses - sinusitis
Lungs - cavitating nodules
Kidneys - glomerulonephritis
Thyroid calcification differential
Microcalcification - papillary thyroid carcinoma
Coarse calcification - medullary thyroid carcinoma
BTA classification of thyroid nodules?
U1 - normal
U2 - benign - hyperechoic / ring down / microcystic
U3 - indeterminate - hypoechoic with equivocal echogenic foci (calc)
U4 - suspicuous - solid hypoechoic
U5 - malignant - solid hypoechoic, lobulated, with microcalc/macrocalc, taller than wide, vascularity, lymphadenopathy
Further investigation of U3-5 thyroid lesions?
FNA
MDT discussion
Repeat FNA in instances of thy1 (non-diagnostic), thy3a/thy3f (neoplasm possible) or thy4 (suspicious) results.
Midline neck mass differential?
Lymphadenopthy
Thyroglossal duct cyst
Thyroid/parathyroid lesion
Ranula
Cystic hygroma
Vascular malformation
Graves vs Hashimotos thytoiditis imaging appearances?
Graves - hyperthyroidism, thyroid inferno doppler, increased uptake on Tc99m pertechnetate
Hashimotos - HYPOthyroidism, heterogenous, giraffe skin, low on pertechnetate, high on PET
Medullary thyroid cancer associations?
MEN IIa and MENIIb
Antrochoanal polyp vs mucocele
Antrochoanal polyp
- Widening of the maxillary ostium and extention into nasopharynx,
- enlargment of sinus,
- no bony destruction
Mucocele
- Contained within maxillary sinus
- can have bony destruction
Inverted papiloma vs esthesioneuroblastoma
Cribiform plate lesions
Inverted papilloma - cerebreform appearance
Esthesio - dumbell shape, extends upwards towards brain.
Ranula vs plunging ranula
Ranula - sublingual mucous retention cyst
Plunging ranula - crosses the mylohyoid into the submandibular space
Parotid gland tumours?
Pleomorphic adenoma
Warthin tumour
Mucoepidermoid
Adenoid cystic carcinoma
Lymphoma
Warthin vs Pleomorphic adenoma
Warthin has increased uptake on Tc99m Pertechnetate.
Bilateral parotid tumours?
Warthins
Lymphoma
(Sjogrens, HIV, sarcoidosis)
Where do mucoepidermoid and adenoid cystic carcinoma typically affect?
Minor salivary glands - the small and unnamed salivary glandular tissue scattered throughout the oral cavity
Masticator spaces malignancy/infection can spread to which other structures?
Cavernous sinus or orbital apex via the pterygopalatine fossa
What 4 spaces surround the parapharyngeal space?
Anterior - masticator space
Lateral - parotid space
Posterior - carotid space
Medial - superficial mucosal space
Necrotic retro pharyngeal lymph nodes suggest what pathology?
SCC metastatic nodal disease
Papillary thyroid carcinoma nodal disease
What Tolosa Hunt syndrome?
Cavernous sinus and orbital apex inflammation
Intraconal lesions?
Nerve:
Optic nerve glioma
Optic nerve meningioma
Vessels”
Cavernous haemangioma (AMV)
Orbital varix
Muscles:
Orbial pseudotumour
Globe:
Retinoblastoma
Extraconal lesions?
- Infection
- Dermoid cyst
- Lacrimal gland lesions
- Capillary/cavernous haemangioma
Lacrimal gland lesions?
Inflammatory - sarcoid, sjogrens
Benign - pleomorphic adenoma, dermoid cyst
Malignant - Adenoid cystic, mucoepidermoid, lymphoma
What is the most common malignant orbital tumours in childhood?
Rhabdomyosarcoma
Retinoblastoma
Children with bilateral retinoblastomas are also at risk of which other tumours?
Trilateral renitoblastoma - Bilateral retinoblastoma and pineoblastoma
Quadrilateral retinoblastoma - Bilateral retinoblastoma, pineoblastoma, suprasella tumour.
Osteosarcoma
What order does thyroid eye affect the eye muscles?
IM SLO
Inferior
Medial
Superior
Lateral
Oblique
Vascular malformations of the eye differential?
Venous varix - increase size on straining
Cavernous haemangiomas - slow irregular enhancment
Carotocavernous fistula - pulsatile expothalmous
What is the most common cause of exophthalmos after a viral illness in children?
Orbital lymphangioma
Cholesteatoma vs cholesterol granuloma
Cholesteatoma - low T1, high T2, restricts
Granuloma - high T1, high T2, no restriction
Thing to assess when looking at cholesteatoma?
Oscicles
Scutum
Tegmen tympani
Classic imaging appearance of ameloblastoma?
“Soap bubble” appearance
Resorption of adjacent teeth
Avidly enhancing papillary projections are common
Age group of capillary Vs cavernous hemangiomas of the orbit?
Capillary hemangioma - child
Cavernous hemangioma - adults
Typical appearance of a cricopharyngeal bar?
Posterior oesophageal indentation at C5-C6.
Cavernous hemangioma MRI appearance?
T1 - iso to muscle
T2 - hyperintense to muscle, dark capsule
Gd - slow irregular enhancement
Papilliary necrosis differential?
Diabetes
TB - early phase
Sickle cell
How can you tell the difference between pleomorphic xanthoastrocytoma, pilocytic astrocytoma, and haemangioblastoma?
All 3 appear as cyst with enhancing nodule.
Pleomorphic xanthoastrocytoma - Supratentorial, in temporal lobe
Pilocytic astrocytoma - Posterior fossa in kids (NF1)
Haemangioblastoma - Posterior fossa in adults (VHL)
Posterior fossa masses?
4th ventricle tumours - ependymoma, medulloblastoma
Cyst with nondules - haemangioblastoma adult, pilocytic astrocytoma child
Brain stem gliomas
Pheochromocytomas are associated with what conditions?
NF1
MEN IIa + MEN IIb
VHL
Mosaic attenuation differential?
Air trapping - hypersensitivity, CF, MAI
Vascular occlusive disease - CTEPH
Parenchymal disease - ground glass (infection, haemorrhage)
Mosaic attenuation differential?
Air trapping - hypersensitivity, CF, MAI
Vascular occlusive disease - CTEPH
Parenchymal disease - ground glass (infection, haemorrhage)
Soft tissue sarcoma differential?
Undifferentiated pleomorphic sarcoma
Synovial sarcoma
Liposarcoma
Rhabdomyosarcoma
Most common HIV related abscess in brain?
Toxoplasmosis
How to differentiate between CNS Toxoplasmosis Vs Lymphoma in HIV patients?
Toxoplasmosis - multiple lesions, peripheral haemorrhage, ring enhancement, restricted diffusion
Lymphoma - single lesion, no haemorrhage, solid enhancement, facilitated diffusion.
How does coarctation or aorta cause rib notching?
If the stenosis occurs distal to either subclavian artery, collateral pathways form via the internal mammary - intercostal artery - descending thoracic aorta, to supply the rest of body.
If the stenosis occurs between the subclavian arteries, then you get unilateral right sided collateral formation.
Types of breast cancer?
DCIS
Intra lobular carcinoma
Intraductal carcinoma
Phyloides tumour
Signal characteristics of endometrioma?
T1 high
T2 low (shading)
May have wall enhancement
Brain stem high signal?
Demyelination - MS, subacute combined degeneration, osmotic degeneration (alcoholics)
Brain stem stroke.
Infection - herpes myelitis
Syrinx
Adrenal tumours?
Adrenal cortical carcinoma - large heterogenous lesions
Phaechromocytoma - smaller heterogenous lesion
Adrenal myelolipoma - fat containing
Adenoma - small, <10 HU non-contast CT
Choroid plexus tumours?
Choroid plexus papilloma
Choroid plexus carcinoma
Types of osteochondromatosis?
Primary
Secondary - caused by degeneration
Tamoxifen endometrium changes?
Thickness upto 12mm
Sub endometrial cysts
Endometrial polyps
Calcified brain tumours differential?
Supratentorial - oligodendroglioma, ganglioglioma, cavernous haemangioma
Ventricular - ependymoma, subependymoma, central neurocytoma, choroid plexus papilloma
Pineal - pineoblastoma
Bilateral thalamic infarcts differential?
Cerebral vein thrombosis
Artery of Percheron infarct
H shaped vertebrae differential?
Sickle cell
Gaucher’s
Calcified pulmonary metastasis differential?
Sarcomas - Osteosarcoma, chondrosarcoma
Mucinous - Ovarian/appendix
Medullary thyroid cancer
Pseudoarthrosis differential?
NF1
Fracture non union
Ehlers danlos
Osteogenesis imperfecta
Bowed leg differential?
Rickets
Blount disease
NF1
Osteogenesis imperfecta
Globe calcification differential?
Retinoblastoma
Choroidal osteoma (tuberous sclerosis)
Drusen
Klippel trenaunay syndrome triad?
Limb overgrowth
Varicose veins
Port wine naevi
Calcified adrenal glands differential?
Previous TB
Neuroblastoma
Haemorrhage
Wolman disease
Bilateral CPA angle masses differential?
Scwannoma - NF2
Sarcoidosis
Metastases
Non accidental injury skeletal survey protocol?
Chest with oblique rib views
Abdomen and pelvis
Whole spine view
Limb views
CT Head all children <1yo
CT Head children >1yo if suspicion of head injury
Repeat skeletal survey in two weeks
Any suspicious areas
Chest with oblique rib views
Limb views
Non accidental injury highly suspicious injuries?
Posterior rib fractures
Metaphyseal corner fractures
Scapula
Spinous process
Sternal fracture
Subdural haematoma
Retinal haemorrhage
Neonatal bowel obstruction differential?
Proximal:
- Oesophageal atresia
- Duodenal atresia, stenosis, web
- Annual pancreas
- Malrotation
Distal:
- Hernia
- Ileal atresia
- Colonic atresia, stenosis
- Meconium ileus, plug syndrome (CYSTIC FIBRROSIS)
- Hirschprung disease
- NEC
Manifestations of cystic fibrosis?
Pulmonary:
- Bronchiectasis
Abdominal:
- Pancreatitis
- Fatty replacement of pancreas
- Distal intestinal obstruction syndrome
- Meconium ileus/plug
Head and neck:
- Sinusitis
Imaging findings of autoimmune pancreatitis?
Sausage shaped pancreas
Minimal peripancreatic fat stranding
Peripancreatic low attenuation halo
Management of lung cancer on CXR
CT Thorax and upper abdomen including liver and adrenals
Lung MDT discussion
MRI Brain
Biopsy, coaxial needle 16- 18 gauge
Lytic bone lesion management
Compare previous
Chest Xray if in the department or CT TAP
Well defined lung lesion with central calcification differential
Hamartoma
Lipoma
Carcinoid tumour
Benign narrow zone of transition bone tumour differential?
ABC / Simple bone cyst
Brown tumour
Enchondroma
NOF
Wide zone of transition bone pathology differential?
Mets
Myeloma
Lymphoma
Eosinophilic granuloma
Osteosarcoma
Osteomyelitis
Rib lesion differential?
FAMES
Fibrous dysplasia
ABC
Mets/myeloma
Enchondroma/eosinophilic granuloma
Sarcoma
Management of suspected sarcoma Vs mets/myeloma?
Sarcoma:
- Refer sarcoma centre
- Don’t biopsy
- Look for skip lesions (MR entire bone)
- Look for mets (CTTAP)
Mets/myeloma:
- Oncology MDT
- CTTAP
- Myeloma screen
- Biopsy
Causes of perfusion defect Vs matched defect on VQ scan?
Perfusion - PE, Vasculitides
Matched - Asthma, pneumonia
How do you define recurrent UTI?
3 or more episodes of lower UTI
1 episode lower UTI + 1 pyelonephritis
2 episodes of pyelonephritis
Paediatric NICE guidlines UTI follow up imaging guidelines?
Younger than 6 month with recurrent or atypical UTI:
- USS
- DMSA
- MCUG
Between 6 months and 3 years
- DMSA
- MCUG only if hydronephrosis, NON Ecoli infection, or reduced urine flow
Over 3 years:
- DMSA with recurrent UTI
Perform the DSMA scan 4-6 months post UTI
Germinal matrix haemorrhage grading?
Grade 1 - confined to Germinal matrix
Grade 2 - extension into ventricles <50%
Grade 3 - extension into ventricles >50%, or dilated ventricles
Grade 4 - extension into venous infarction
Optic nerve glioma Vs optic nerve sheath meningioma?
Optic nerve glioma
- optic nerve thickening
- kinking and buckling of the optic nerve
- no calc
- variable enhancement
Optic nerve sheath meningioma
- nerve sheath thickening, sparing of nerve (tram track sign)
- calcification is common
- bright enhancement