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Adrenal dysfunction

Diagnosed clinically and biochemically Imaging to identify causal lesion, unilateral or bilateral, plan surgical or medical management Types  Cortical hyperfunction Cushing’s syndrome Conn’s syndrome Adrenogenital syndrome Medullary hyperfunction Adrenal medullary hyperplasia Pheochromocytoma Cortical hypofunction Addison’s disease Secondary cortical insufficiency (due to decreased ACTH)

Adrenal myelolipoma

Rare Benign, non-functioning Adrenocortical dysfunction in 10% <5 cm, solitary Hematopoietic precursor cells and mature adipose tissue  May have fibromyxoid degeneration, hemorrhage, necrosis, calcification Asymptomatic  Large lesions sometimes cause abdominal pain or retroperitoneal bleeding Imaging  Recognizable capsule May have calcification Varying amounts of fat Myeloid soft tissue component enhances with contrast Fat attenuation < -30 […]

Adrenal cysts

Endothelial cyst Vascular cyst Endothelial lining 45% of adrenal cysts 2/3 in females 8% bilateral May have residual adrenocortical tissue in wall  Hemorrhagic cyst Pseudocyst 39% of adrenal cysts Middle-aged women  Seen in Beckwith-Wiedemann syndrome Originally would have been an endothelial cyst, that underwent hemorrhage, and secondary fibrosis or hemosiderin deposition Parasitic cyst Echinococcal Asymptomatic […]

Imaging an adrenal mass

Incidental masses in 5% of abdominal scans 6% of people >60 years carry an adrenal adenoma. 70-80% of these are non-functioning Prevalence of 9-13% in patients with an extra-adrenal malignancy In a patient with known carcinoma, only 26 – 36% are metastatic  European Society of Endocrinology Clinical Practice Guidelines for adrenal masses Unenhanced CT should […]

Transplant pancreas imaging

Graft rejection is best demonstrated by MRI T1 drop in signal to similar to skeletal muscle T2 signal similar to fluid  Perfusion studies will demonstrate decreased blood flow Acute rejection: Gland will be swollen with patchy areas of decreased attenuation Chronic rejection: gland is diffusely hyper echoic and reduced in size Tc 99m DTPA is […]

Multi-system disease involving pancreas

Cystic fibrosis Autosomal recessive Defects of serous and mucous secretion 85% have exocrine pancreatic insufficiency, steatorrhea  Main duct and branch ducts obstructed by inspissated secretions Acinar and ductal dilatation Atrophy of pancreas Fatty replacement, dystrophic calcification, pancreatic cysts Autosomal dominant polycystic kidney disease 10% patients show pancreatic cysts Von Hippel-Lindau disease Autosomal dominant Renal cell […]

Metastasis to pancreas

Rare, occur late in disease Lung, breast, kidney and melanoma 3 patterns described: multiple small nodules, diffuse infiltration, solitary mass Kidney origin lesions may appear hyper enhancing and mimic neuroendocrine tumors

Intraductal papillary mucinous tumor of pancreas (IPMT)

Most common cystic pancreatic neoplasm  Arise from epithelial cells of main duct or side branches   Produces large amount of mucin  4 histological types: dysplasia, borderline, carcinoma in situ, IPMT with invasive cancer  Based on location: main duct type, branch duct type or mixed type   Diffuse or segmental duct dilatation   Mixed type shows diffuse and segmental […]

Serous cystic neoplasms of pancreas

Mass consisting of numerous tiny cysts, at least 6 in number, each cyst <2 cm in diameter  May show central scar or stellate calcification   If cysts too small to discern, it will appear as a solid mass.  MRI clearly depicts the microcystic nature   Very rarely it can appear in a macrocystic form and be difficult to distinguish […]

Mucinous cystic neoplasms of pancreas

Benign to malignant, eventually turn malignant  Mass consisting of few >2 cm sized cysts  Any accompanying solid component suggests malignancy 

Neuroendocrine tumors of pancreas

Functioning or non-functioning depending on hormonal hyper secretion Functioning tumors produce a peptide hormone and has a clinical syndrome Non-functioning tumors have a better prognosis Insulinoma, gastrinoma, glucagonoma, VIPoma, somatostatinoma  20% NETs are partially cystic, 3% purely cystic Insulinoma Hypoglycemic episodes Solitary, benign 80% cases <2 cm size Treated by surgical resection Gastrinoma Second most […]

Ductal adenocarcinoma of pancreas

Aggressive  Early advanced local or distant spread Perivascular, perineurial and lymphatic spread Early spread to liver and peritoneum At time of diagnosis, only 10% cases surgically resectable 5 year survival rate <5% Radical pacreaticoduodenectomy – severe morbidity and mortality Weight loss, anorexia common symptoms Obstructive jaundice seen in tumors involving head of pancreas CA 19-9 […]

Autoimmune pancreatitis

No history of alcohol use or biliary stone disease Immune-mediated Gland infiltrated by CD4 positive lymphocytes and plasma cells Serum IgG4 sometimes elevated Responds to steroids Focal form difficult to distinguish from malignancy May be associated with other IgG4 issues: cholangitis, renal, salivary gland or lacrimal gland inflammation, lymphadenopathy Imaging  3 types in imaging: diffuse, […]

Chronic pancreatitis

Irreversible inflammation and fibrosis Multiple prior attacks of acute disease Abdominal pain Loss of exocrine and endocrine function Weight loss, steatorrhea, diabetes Diagnosis made when 3 of the following 4 is present Parenchymal calcifications Intraductal calcifications Parenchymal atrophy Cystic lesions Focal pancreatitis and malignancy in chronic pancreatitis are hard to distinguish on imaging. One sign […]

Acute pancreatitis

Some etiologies Alcohol, cholelithiasis, trauma, iatrogenic, hyperlipidemia, hypercalcemia, viral infections (CMV, mumps), drugs, idiopathic Clinical diagnosis Needs at least 2 of the 3 below: Abdomen pain strongly pointing to acute pancreatitis Serum amylase and or lipase at least 3 times upper limit Characteristic imaging findings  Revised Atlanta Classification (2008) Two morphological types: interstitial edematous and […]

Annular pancreas

Second most common congenital anomaly Failure of normal rotation during development Pancreas partially or completely encircles duodenum Sometimes causes symptomatic duodenal narrowing Barium studies show narrowing at level of major papilla Quite often asymptomatic CT, MRI shows the tissue around second part of duodenum ERCP or MRCP will show the duct encircling the duodenum

Pancreas divisum

Commonest congenital pancreatic abnormality Failure of normal fusion of dorsal and ventral anlage  Dorsal and ventral ducts don’t fuse Wirsung (ventral duct) drains head of pancreas via major papilla Santorini (dorsal duct) drains body and tail via minor papilla Can cause functional stenosis of minor papilla and secondary pancreatitis Higher prevalence in patients with recurrent […]

Genetic screening in breast cancer

Recommendations for hereditary breast cancer 1 in 8 to 1 in 12 women develop breast cancer in their lifetime National Comprehensive Cancer Network guidelines for genetic counseling referral  Patient with personal history of breast cancer Diagnosis < 50 years of age  Triple negative breast cancer diagnosed at <60 years of age Personal history of two […]

Alcohol and the brain

Central nervous system depressant primary interfering with GABA receptors Pleasure comes from release of endorphins and dopamine Acute phase usually CT is done Quite often CT is normal Sometimes mild cerebral edema is seen in the form of effacement of sulci and reduced size of ventricles Chronic phase Non specific atrophy: atrophy disproportionate for age […]

Multiple sclerosis

Introduction 40-50 years age Relapsing-remitting type 85% Primary-progressive type 15% Characteristic abnormality – demyelinating plaques Location of plaques – middle cerebellar peduncle, callososeptal interface, periventricular white matter, juxtacortical Callososeptal interface involvement – pathognomonic Imaging Plaque character Initial stages: acute, with surrounding edema Remyelination may occur: resulting in target lesions in pathology Eventually, chronic stage: axon […]

Progressive supranuclear palsy

Introduction Parkinsonism Supranuclear ophthalmoplegia Pseudobulbar palsy dementia Imaging Humming bird sign: concave upper mid brain border in sagittal image Mickey mouse sign: reduced anteroposterior mid brain diameter < 14 mm with deepening of interpeduncular cistern

Multiple system atrophy

Introduction Sporadic progressive neurodegenerative disorder Adulthood onset Glial cytoplasmic inclusions containing alpha synuclein Combination of cerebellar, autonomic, extra-pyramidal and pyramidal signs MSA-P: predominant parkinsonian features MSA-C: predominant cerebellar dysfunction Imaging MSA-C: reduced pontine volume. Cerebellar atrophy. Cruciform T2 pontine hyperintensity (hot cross bun sign) MSA-P: also shows excess mineralization of bilateral putamina and substantia nigra

Parkinson’s disease

Introduction Progressive neurodegenerative movement disorder Involves basal ganglia Hypokinetic disorder Impaired initiation of movement Reduction in amplitude and velocity of movement 1.5 times more common in men Usually after 60 years age Degeneration of cells in pars compacta of substantia nigra Symptoms appear after 50% of dopaminergic neurons and 80% of striatal dopamine is depleted […]

West syndrome

Triad of myoclonic seizures hypsarrhythmic electroencephalogram developmental delay

Normal pressure hydrocephalus

gait disturbance dementia urinary incontinence communicating hydrocephalus normal measured pressure mostly idiopathic only some patients improve with shunting

Medullary bone lesions

Lucent, well defined, marginal sclerosis with no expansion Geode healing benign or malignant lesion Brodie’s abscess simple bone cyst enchondroma chondroblastoma fibrous dysplasia lucent, well defined, no marginal sclerosis, no expansion metastases – breast, bronchus, kidney, thyroid multiple myeloma eosinophilic granuloma brown tumor enchondroma chondroblastoma lucent, ill defined metastasis multiple myeloma osteomyelitis lymphoma osteosarcoma Ewing’s […]

Luxatio erecta

inferior dislocation of shoulder due to severe arm hyperabduction humeral head impinges upon acromion which acts as a fulcrum arm is locked in abduction

Bankart lesion

fracture of anteroinferior glenoid rim labrum may be displaced increased risk of recurrent dislocations fluid extending between glenoid and labrum is primary sign of labral tear associated bony injury of glenoid rim is a bony Bankart

Hill-Sachs fracture

V-shaped deformity of humeral head due to impaction of anterior glenoid rim on posterosuperior humeral head increased risk of recurrent dislocations

Chance fracture

horizontal splitting of vertebral body little compression associated intra abdominal and neurological injuries mechanism anterior hyperflexion over an object (seatbelt) that acts as a fulcrum posterior ligaments intact if any ligament injury is present, epidural fat will be dirty soft tissue chance injury: posterior ligament injury without bony injury radiograph transverse/horizontal fracture of spinous process […]

Clay shoveller’s fracture

C6-T1 spinous process avulsion mechanism rotation of upper trunk with a fixed cervical spine occasionally due to a direct blow stable injury

Flexion teardrop fracture

fracture-dislocation with spinal cord injury mechanism hyperflexion and axial compression unstable injury radiograph triangular fragment at anteroinferior aspect of involved vertebral body (teardrop) anterior vertebral body height reduction with soft tissue swelling posterior displacement of fractured vertebra diastasic of interfacetal joints longitudinal ligament, intervertebral disc and posterior ligament complex disruption

Hangman’s fracture

traumatic spondylolisthesis of C2 with fracture through both pedicles posterior elements separated from vertebral body fracture lines oblique and symmetrical anteroinferior C2 margin may be avulsed C2 body subluxes anteriorly to C3 but posterior elements remain aligned mechanism hyperextension injury unstable injury

Jefferson fracture

disrupted anterior and posterior arches of atlas mechanism axial compression injury to top of skull stable injury radiograph bilateral offset of lateral masses of C1 relative to lateral margin of C2 vertebral body widened space between dens and medial border of C1 lateral masses

Succenturiate lobe of placenta

accessory lobe separate mass of chorionic villi connected to main placenta by vessels within membrane etiology placental villi atrophy in area of inadequate blood supply. proliferation occurs in two opposite directions with fetal vessels remaining in site of atrophy complications retained in utero with post partum hemorrhage placenta previa with post partum hemorrhage vasa previa

Mayer Rokitansky Küster Hauser syndrome

1 in 4000-5000 second most common cause of primary infertility vaginal agenesis or proximal and middle segment hyperplasia intact ovaries and fallopian tubes varying uterine anomalies – agenesis, hypoplasia, uni or bicornuate renal agenesis, pelvic kidney normal external genitalia amenorrhea cyclic pelvic pain

Velamentous cord insertion

umbilical cords inserts into membranes before entering placenta associations multiple gestation uterine anomalies intrauterine death fetal anomalies: spina bifida, esophageal atresia, obstructive uropathy, VSD, cleft palate complications IUGR preterm labor cord compression rupture of cord with traction

Extension tear drop fracture

fracture of anteroinferior corner of body of C2 avulsed by an intact anterior longitudinal ligament no associated neurological deficit occurs in isolation or with hangman’s fracture occasionally involves lower cervical vertebral bodies an unstable extension injury

Peak age incidence of primary bone neoplasms

First to second decade simple bone cyst Ewing’s sarcoma chondroblastoma second to third decade osteochondroma osteoblastoma osteosarcoma osteoid osteoma aneurysmal bone cyst chondromyxoid fibroma third to fourth decade glant cell tumor lymphoma fibrosarcoma malignant fibrous histiocytoma mid 30s to mid 50s osteoma parosteal osteosarcoma first to fifth decade chondroma third to seventh decade hemangioma chondrosarcoma […]

Coarse trabecular pattern

Paget’s disease osteoporosis osteomalacia haemoglobinopathies – thalassemia hemangioma Gaucher’s disease

Bone sclerosis with a periosteal reaction

healing fracture with callus metastasis lymphoma osteoid osteoma osteoblastoma osteosarcoma Ewing’s sarcoma chondrosarcoma osteomyelitis syphilis infantile cortical hyperostosis melorheostosis

Multiple sclerotic bone lesions

fibrous dysplasia osteopoikilosis osteopathia striata tuberous sclerosis metastases: prostate, breast lymphoma mastocytosis multiple myeloma osteomata Paget’s disease bone infarcts callus

Solitary sclerotic bone lesion

bone island fibrous dysplasia metastasis: prostate, breast lymphoma osteoma osteoid osteoma osteoblastoma healed benign or malignant lesion primary bone sarcoma bone infarct callus Garre’s sclerosing osteomyelitis Paget’s disease

Tumoral calcinosis

juxta articular calcified soft tissue masses normal serum calcium and phosphorus no renal, metabolic or collagen vascular disease autosomal dominant abnormal phosphate reabsorption 1st-2nd decade M=F blacks clinical progressive soft tissue mass with skin ulceration, sinus tract draining chalky milk like fluid swelling restricted motion hyperphosphatemia hypervitaminosis D normal serum calcium, ALP, renal function, parathyroid […]

Turner syndrome

monosomy 45, XO 1 in 3000-5000 skeletal growth arrest at 15 years Cardia coarctation aortic stenosis idiopathic hypertension lymphangiectasia, generalized hydros head and neck webbed neck high palate low irregular nuchal line nuchal cystic hygroma endocrine thyromegaly pigmented nevi, keloid formation sexual infantilism primary amenorrhea absent secondary sex characteristics raised urinary gonadotrophins chest wide spaced […]

Bonnevie-Ullrich syndrome

infantile form of Turner syndrome congenital webbed neck widely separated nipples hand and feet lymphedema

Turret exostosis

dorsum of proximal or middle phalanx of hand painful lump trauma and formation of subperiosteal hematoma immobile ossified hematoma seen as smooth dome-shaped extracortilal mass

Ulnar collateral ligament tear

chronic overuse throwing, over head motion (tennis serve) excess valgus stress clinical increasing pain medial elbow paresthesia forearm, 4th 5th digits radiograph ulnar collateral ligament ossification loose bodies ulnohumeral osteoarthritis capitellum osteochondritis dissecans excess medial joint opening in stress radiograph MRI lax, discontinuous ulnar collateral ligament high T2 signal of UCL and soft tissue around […]

Van Buchem disease

generalized cortical hyperostosis chromosome 17 defect autosomal recessive clinical facial nerve palsy auditory and ocular symptoms increased ALP MSK skull, mandible, clavicles, ribs, long-bone diaphyses generalized sclerosis thick endosteal cortex diploe is obliterated thick sclerotic spinous process

Williams syndrome

idiopathic hypercalcemia of infancy neonatal hypercalcemia MSK osteosclerosis dense broad zone of provisional calcification bone islands in spongiosa dense vertebral end plates radiolucent metaphyseal bands craniosynostosis Cardio supravalvular aortic stenosis aortic hypoplasia valvular pulmonary artery stenosis ASD VSD Abdomen colonic diverticula bladder diverticula

Wilson disease

hepatolenticular degeneration autosomal recessive excess copper retention chromosome 13 alteration – liver unable to excrete copper into bile 7-50 years hepatic findings in children neuropsychiatric findings in adults stages Stage 1 asymptomatic copper accumulation in liver cytosol Stage 2 redistribution of copper from hepatic lysosomes. when gradual it is asymptomatic, if rapid redistribution, presents with […]

Diffuse esophageal spasm

dysmotility disorder five times less common than achalasia strong repetitive non-propulsive contractions interspersed with normal peristaltic waves these contractions may obliterate esophageal lumen sometimes presents with chest pain barium swallow corkscrew or curling esophagus due to strong non-propulsive contractions marked esophageal wall thickening due to high pressure, occasionally diverticula may be seen

Joubert syndrome

total aplasia of cerebellar vermis failure of formation of decussation of superior cerebellar peduncles lack of pyramidal decussations other anomalies of midbrain crossing tracts and their nuclei associated anomalies: renal cysts, ocular abnormalities, liver fibrosis, hypothalamic hamartomas, polymicrogyria clinical presentation tachypnea abnormal eye movements ataxia occasionally clinically normal MRI cleft within vermis small midbrain superior […]

Cotswold’s modification of Ann Arbor staging of Hodgkin’s disease

Stage Classification I involvement of single lymph node region (I) or a single extralymphatic organ or site (IE) II involvement of two or more lymph node regions on the same side of the diaphragm (II) or on one or more lymph node regions plus an extralymphatic site (IIE) III involvement of lymph node regions on […]

Barrett’s oesophagus

due to chronic gastro-oesophageal reflux causes a specialized non-secretory columnar epithelium to grow cranially in previous site of squamous epithelium 2 cm or more of columnar epithelium needed to reach this diagnosis may develop high grade dysplasia 40 fold risk of developing esophageal carcinoma. 15% develop adenocarcinoma >2 cm involvement needs 2 yearly endoscopic surveillance […]

Rathke’s cleft cyst

arise from embryologic remnant of Rathke’s pouch lies within pituitary gland, found adjacent to infundibulum (above the sella) usually asymptomatic MRI T1 high signal intensity, sometimes similar signal to CSF T2 variable signal intensity No enhancement post Gd, wall is thin and smooth and may show mild enhancement


endometrial tissue in myometrium secondary smooth muscle hypertrophy and hyperplasia diffuse or focal clinical presentation dysmenorrhea dysfunctional uterine bleeding ultrasound enlarged, globular uterus myometrial heterogeneity echogenic myometrial nodules subendometrial echogenic linear striations 2-6 mm subendometrial cysts endometrial pseudowidening: poor definition of endomyometrial junction rain shower appearance: multiple fine areas of attenuation throughout the lesion doppler: […]

Optic nerve glioma

pilocytic astrocytoma occurring in childhood involves optic nerves, chiasm and optic tracts chiasmal lesions often extend to hypothalamus and is of a higher histological grade associated with NF-1 (chiasmatic uncommon) indolent clinical course MRI iso to hypointense of T1 hyperintense on T2 variable Gd+ enhancement diffuse fusiform expansion of nerve can occur from subarachnoid dissemination

Ethanol intoxication

characteristic neuroparenchymal volume loss initial infratentorial predominance with vermian and cerebellar atrophy followed by frontal and temporal atrophy finally diffuse brain atrophy

Commercially available gadolinium-based contrast agents

ACR, FDA and EMA have classified Gadolinium-based contrast agents into three groups Group Type US Trade Name Chemical Name I linear, non-ionic Omniscan gadodiamide linear, non-ionic OptiMARK gadoversetamide linear, ionic Magnevist gadopentate dimeglumine II linear, ionic MultiHance gadobenate dimeglumine macrocyclic, non-ionic ProHance gadoteridol macrocyclic, non-ionic Gadavist gadobutrol macrocyclic, ionic Dotarem gadoterate meglumine III linear, ionic […]

Yellow flags of low back ache

Yellow flags represent the psychosocial barriers to recovery that may increase the long-term disability and work loss belief that pain and activity are harmful ‘sickness behaviors’ low or negative moods, social withdrawal treatment beliefs do not fit best practice problems with claim and compensation history of back pain, time-off, other claims problems at work, poor […]

Red flags in low back ache

If any of the following flags are seen in a patient with low back ache, imaging with MRI is recommended. CT only if MRI is contraindicated. cauda equina syndrome (urinary retention, faecal incontinence, saddle anesthesia) severe unremitting worsening of pain at night – infection or tumor significant trauma – fracture unexplained weight loss, fever, HIV, […]

Harborview high-risk criteria for cervical spine injury

Computed tomography is indicated in any of the following criteria presence of significant head injury presence of focal neurological deficit(s) presence of pelvic or multiple extremity fractures combined impact of accident >50 km/h death at the scene of motor vehicle accident accident involved fall from a height of 3 meter or more Harborview high-risk criteria

Wells clinical prediction rule for pulmonary embolism

Criteria Points previous pulmonary embolism or deep venous thrombosis 1.5 heart rate > 100 beats per min 1.5 surgery or immobilization < 4 weeks 1.5 hemoptysis 1 active cancer 1 clinical signs of deep venous thrombosis 1 alternative diagnosis less likely than pulmonary embolism 3 Pulmonary embolism is likely if > 4 points

Pseudocoarctation of aorta

elongated aortic arch bulges posteriorly above the point it is fixed by the ligament produces 3 sign similar to true coarctation in a frontal radiograph no accompanying hemodynamic obstruction

Aortic atresia

associated with hypoplastic left heart syndrome ascending aorta smaller than brachiocephalic artery blood flows from heart to aorta via pulmonary trunk and persistent ductus. Arch fills retrograde normal origin of brachiocephalics coronaries arise from ascending aorta survival depends on PDA patency Norwood operation: converts morphological right ventricle into systemic ventricle, anastomosing pulmonary trunk to ascending […]

Facet joint osteoarthritis grading

Weishaupt et al. refined grading of Pathria et al. to grade facet joint osteoarthritis on CT and MRI Grading Grade 0 normal facet joint space (2-4 mm width) Grade 1 narrowing of joint space (<2 mm) and/or small osteophytes and/or mild hypertrophy of articular processes Grade 2 narrowing of joint space and/or moderate osteophytes and/or […]

Communicating discs to clinicians

The Combined Task Forces classification based on anatomical boundaries used by surgeons transverse / axial plane central (posterior midline) paracentral (right/left central) right/left subarticular (lateral recess) right/left foraminal (neural foramen) right/left extraforaminal (outside neural foramen) anterior zone (anterior and anterolateral) vertical / sagittal plane pedicle level infrapedicle level disc level suprapedicle level

Disc herniation

displacement of disc material beyond limits of intervertebral disc space what is disc material? cartilage, nucleus, fragmented annular tissue and apophyseal bone break in vertebral end plates or disruption in annulus fibrosus needed for herniation to occur TYPES extrusion base against the disc is smaller than diameter of displaced disc material (measured in same plane […]

Disc bulge

circumferential or generalized disc displacement >50% of disc circumference etiology physiological at L5-S1 advanced degenerative changes pseudo image due to partial volume effect related to bone remodeling or ligament laxity types symmetrical – uniform in all directions asymmetrical – seen in scoliosis

Limbus vertebra

in young individuals herniation of nucleus pulposus through ring apophysis before bony fusion as a result small segment of vertebral rim gets isolated more common in lumbar region, less common in mid cervical level defect in anterior wall of vertebra usually in anterior superior margin lumbar spine and anterior inferior margin in cervical spine

Schmorl’s nodes

also called intervertebral herniations disc displacement through one or both vertebral end plates break in vertebral end plates or disruption of annulus fibrosus surrounded by reactive bone marrow changes hypothesis: regression of nutrient vascular canals in the end plate causes a weak spot resulting in herniation

Modic vertebral degeneration

degenerative changes in vertebral end plates and bodies described by Modic in 1988 type I decreased signal intensity on T1 increased signal intensity on T2 inflammatory stage shows bone marrow edema type II increases signal intensity on T1 increased or intermediate signal intensity on T2 fatty stage local fatty replacement of bone marrow type III […]


midline anterior abdominal wall defect solid viscera or bowel may herniate extruded contents covered in a sac large lesions: due to complete failure of fusion of lateral body folds bowel only lesions: due to persistence of physiological herniation of gut after 10th week of fetal development umbilical cord inserts at tip of defect giant omphalocele: […]


small split in ventral abdominal wall usually to right of umbilicus no associated anomalies due to intrauterine vascular accident or asymmetry in lateral body wall folds with failure of fusion seen in mothers < 20 years serious complications: short bowel syndrome, liver disease due to intestinal failure or dysmotility, necrotizing enterocolitis imaging bowels floating in […]

Pericardial cyst

due to persistence of blind ending ventral parietal pericardial recesses cyst that communicates with pericardial space – pericardial diverticula imaging well defined oval or occasionally lobulated right cardiophrenic angle (70%) left cardiophrenic angle (20%) sometimes higher up in mediastinum clear fluid MR: low to intermediate on T1, high on T2 with no post Gado enhancement

Congenital absence of pericardium

rare and usually asymptomatic most common: complete absence of left pericardium associated anomalies: ASD, ToF, PDA, bronchogenic cysts, pulmonary sequestration imaging interposition of lung between aorta and main pulmonary artery in the aortopulmonary windows is the most reliable sign rotation of cardiac axis to the left side


two layers: parietal and visceral normal fluid < 50 ml left atrium partially covered by pericardium normal thickness < 2 mm pericardial sinuses show normally small amount of fluid oblique pericardial sinus behind left atrium (DD: bronchogenic cyst) transverse pericardial sinus behind ascending aorta (DD: aortic dissection, lymphadenopathy) superior pericardial recess lies posterior to ascending […]


free air around mediastinal structures blunt or penetrating trauma, esophageal perforation, iatrogenic, pulmonary infections, gas forming organisms, cocaine inhalation, air extension from pneumothorax air per se is of no clinical significant in mediastinum, maybe mild substernal pain imaging ring around artery sign: air around usually right pulmonary artery sail sign: elevation of thymus air anterior […]

Fibrosing mediastinitis

sclerosing mediastinitis or mediastinal fibrosis fibrous tissue and collagen in mediastinum sequel to infection from histoplasmosis or tuberculosis sarcoidosis, autoimmune diseases, retroperitoneal fibrosis, radiation, drugs (methysergide maleate) SVC obstruction, obstruction to central pulmonary artery or veins two types: focal or diffuse. Focal in tuberculous/ histoplasmosis. Diffuse in idiopathic form, associated with retroperitoneal fibrosis focal: calcified. […]

Acute mediastinitis

rare but life threatening high morbidity and mortality most common causes: post op complications, esophageal perforation (Boerhaave syndrome) Esophageal perforation usually occurs just above gastro esophageal junction leakage from esophagus due to a necrotic neoplasm extension of infection from neck, retroperitoneum or intrathoracic structures ill, high fever, tachycardia, chest pain imaging Chest Xray widening, ill-defined […]

Mediastinal masses

anterior mediastinum Morgagni hernia aortic aneurysm cystic hygroma diaphragmatic eventration thymic tumors retrosternal thyroid mass germ cell tumor lymph nodes (lymphoma) pericardial cyst pericardial fat pad sternal masses middle mediastinum hernia (hiatus/aortic) aortic aneurysm lymph nodes (sarcoid, TB, lymphoma, metastases) foregut duplication cysts neurenteric cyst mediastinal paragangliomas carcinoma bronchus fatty mediastinal tumors / mediastinal lipomatosis […]

Bilateral symmetrical elevation of diaphragm

supine position poor inspiration obesity pregnancy abdominal distension (ascites, intestinal obstruction, abdominal mass) diffuse pulmonary fibrosis lymphangitis carcinomatosa disseminated lupus erythematosus bilateral basal pulmonary emboli painful conditions (after abdominal surgery) bilateral diaphragmatic paralysis

Unilateral elevation of diaphragm

posture – lateral decubitus position (dependent side) gaseous dissension of stomach or colon dorsal scoliosis pulmonary hypoplasia pulmonary collapse phrenic nerve palsy eventration pneumonia or pleurisy pulmonary thromboembolism rib fracture subphrenic infection subphrenic mass

A ring

inferior esophageal sphincter 2-4 cm proximal to B ring thicker ring produced by active muscle contraction

Schatski or B ring

ring of mucosal tissue at lower border of phrenic ampulla marks junction between squamous and columnar epithelium (Z line) usually 2-3 mm thick associated with small sliding hiatus hernia sometimes incomplete, part of it seen as incisural notch (on greater curve of stomach)

Carney complex

autosomal dominant myxoma (heart, breast, skin) abnormal skin pigmentation endocrine abnormalities: primary pigmented nodular adrenocortical disease leading to ACTH- independent Cushing’s syndrome

Malignant thyroid nodule

morphology solid nodules protruding into cystic space no posterior acoustic shadowing incomplete, irregular or thickened halo irregular, lobulated or poorly defined margin microcalcification invasion of adjacent tissues enlarged ipsilateral or bilateral cervical lymph nodes

Multiple endocrine neoplasia (MEN)

Type I parathyroid adenoma or hyperplasia (hyperparathyroidism) pancreatic islet cell tumors pituitary adenoma Type II A parathyroid hyperplasia adrenal medullary tumor medullary thyroid cancer Type II B medullary thyroid cancer adrenal medullary tumor marfanoid features, multiple cutaneous and mucosal neuromas, neurofibromas and gastrointestinal ganglioneuromas

Rib notching

due to external pressure on rib superior rib notching connective tissue disease: rheumatoid arthritis, SLE, Sjogren, scleroderma metabolic: hyperparathyroidism neurofibromatosis restrictive lung disease poliomyelitis Marfan syndrome osteogenesis imperfecta progeria inferior rib notching arterial: coarctation of aorta, aortic thrombosis, subclavian obstruction, cause of pulmonary oligemia venous: superior vena cava obstruction arteriovenous: pulmonary AV malformation, chest wall […]

Tuberculous vertebral osteomyelitis

developing countries, TB endemic areas poverty, malnutrition, overcrowding immunosuppressive states like HIV infection and AIDS spine involvement usually secondary comes from lung or genital tract infection spine TB is 50% of all MSK TB infections Imaging around thoracolumbar junction infection at anterior end of vertebral bodies spreads under longitudinal ligament to involve contiguous vertebrae skip […]

Lines and tubes in neonates

endotracheal tube tip varies with head and neck motion tip should be above carina consider chin position nasogastric tube within stomach nasojejunal tube include weighted tip side hole at duodenojejunal flexure umbilical arterial line tip between T6 and T9 course inferiorly within umbilical artery into internal and common iliac arteries, then into aorta umbilical venous […]

Neonatal pneumonia

occurs perinatally ascending infection from vagina transvaginally during birth hospital acquired infection in post natal period prolonged rupture of membranes is a known risk infant swallows or aspirates infected amniotic fluid or vaginal tract secretions Group B streptococcus most common organism imaging severe acute symptoms first 24-48 hours coarse bilateral asymmetrical alveolar opacification with or […]


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