Radiology

ROENTGEN SIGNS OF LYMPHATIC CHANNEL OBSTRUCTION

1. Backflow
2. Collateral circulation
3. Dilatation of lymph vessels
4. Extravasation
5. Stasis of lymph flow


LEFT TO RIGHT SHUNT IN CONGENITAL HEART DISEASE

1. Atrial septal defect (ASD)
2. Atrioventricular (AV) canal defect, partial or complete
3. Patent ductus arteriosus (PDA)
4. Ventricular septal defect (VSD)


RIGHT-TO-LEFT SHUNT CONGENITAL HEART DISEASE

1. APVC, total (above the diaphragm)
2. Double outlet right ventricle (DORV)
3. Left to right shunt progressing to reversal or high resistance vascularity (Eisenmenger Physiology )
4. Tetralogy of Fallot
5. Transposition of great vessels
6. Tricuspid atresia
7. Truncus arteriosus


TYPES OF DEXTROCARDIA

1. Situs inversus (all visceral organs opposite of normal; slightly increased incidence of cardiac anomalies in 5% to 10% of patients)

2. Dextroposition with situs solitus (cardiac apex displaced into right hemithorax—e.g., hypoplasia of right lung; venolobar S.)

3. Dextroversion with situs solitus (anatomic relations are normal, but cardiac apex is in right side of chest—due to abnormal rotation of embryonic cardiac loop)

4. Dextrocardia with situs ambiguus in asplenia S. (bilateral right-sidedness—absent spleen; three lobes in each lung; left lobe of liver same size as right lobe; malrotation of bowel; cardiac apex in either hemithorax—cardiac anomalies include common atrium; single ventricle; PS; transposition of great vessels; and TAPVR)

5. Dextrocardia with situs ambiguus in polysplenia S. (bilateral left-sidedness—each lung has two lobes; hepatic segment of IVC is absent; cardiac apex is in right hemithorax in 50% of patients—cardiac anomalies include ASD; PAPVR; and interruption of IVC with azygos continuation)


COMPLICATIONS OF MYOCARDIAL INFARCTION REQUIRING RADIOLOGICAL EVALUATION

1. Heart failure
2. Left ventricular aneurysm
3. Pericardial effusion
4. Ruptured interventricular septum
5. Ruptured papillary muscle


COMMON CARDIAC CONDITIONS DIAGNOSED BY ECHOCARDIOGRAPHY

1. Aortic stenosis or insufficiency
2. Bacterial endocarditis
3. Cardiac tumor (esp. myxoma of LA)
4. IHSS
5. Mitral stenosis or insufficiency
6. Mitral valve prolapse (MVP)
7. Myocardiopathy
8. Pericardial effusion
9. Shunts (with evaluation of flow and direction by pulsed Doppler)


COMPLICATIONS OF CENTRAL VENOUS (SUBCLAVIAN, JUGULAR) OR PULMONARY ARTERY CATHETERIZATION

1. Arterial insertion with perforation (esp. subclavian or carotid artery)
2. Catheter embolism; broken, trapped, or occluded catheter
3. Extravascular infusion (e.g., mediastinal; intrapleural; subcutaneous)
4. Infection (local or sepsis)
5. Malpositioned or dislodged catheter (e.g., in RV, IVC, hepatic vein, jugular vein)
6. Perforation of vessel with hematoma, hemothorax, hydrothorax, hemopericardium, or hemomediastinum
7. Pneumothorax
8. Thrombosis (e.g., SVC); thrombophlebitis; pulmonary thromboembolism


ROENTGEN SIGNS OF ALVEOLAR DISEASE (CONSOLIDATION, AIR SPACE PATTERN)

1. Acinar or peribronchiolar nodules
2. Air alveologram and bronchiologram
3. Air bronchogram
4. Butterfly or “bat’s wing” distribution
5. Coalescence (early)
6. Fluffy, ill-defined margins
7. Perihilar, diffuse, segmental or lobar distribution
8. Present soon after onset of symptoms; rapid change


REVERSE BUTTERFLY PATTERN

1. ARDS
2. Contusion of lung
3. Eosinophilic pneumonia (PIE; Löffler syndrome)
4. Pneumonia
5. Sarcoidosis


ROENTGEN PATTERNS OF INTERSTITIAL DISEASE

1. Bronchial disease (e.g., peribronchial thickening; mucoid impaction; bronchiectasis)
2. Discrete miliary nodules
3. Honeycomb lung
4. Kerley lines
5. Small irregular shadows (reticular or reticulonodular pattern)
6. Vascular abnormality (incl. pulmonary arterial, pulmonary venous, or bronchial arterial)


ACUTE DIFFUSE FINE RETICULAR OPACITIES (KERLEY LINES, ACUTE— A, B, AND C)

1. Pneumonia (esp. interstitial—infectious mononucleosis, cytomegalovirus, H. influenzae;
Mycoplasma; atypical mycobacterial; Pneumocystis carinii)
2. Pulmonary edema (esp. heart failure; myocardial infarction; valvular heart disease; renal failure; uremia; fluid overload; drug reaction)
3. Transient tachypnea of the newborn (retained fetal lung fluid); Wilson-Mikity S.; bronchopulmonary dysplasia


KERLEY LINES, CHRONIC—A, B, AND C

1. Bronchogenic carcinoma (lymphangitic spread of tumor)
2. Idiopathic pulmonary fibrosis (IPF)
3. Lymphangitic metastases
4. Pneumoconiosis (esp. silicosis)
5. Mitral stenosis


GROUND-GLASS OPACITIES ON HRCT

1. Hypersensitivity pneumonitis (extrinsic allergic alveolitis) (e.g., farmer’s lung, bagassosis)
2. Nonspecific interstitial pneumonia (NSIP) (idiopathic or associated with collagen vascular disease or AIDS)
3. Acute interstitial pneumonia (AIP)
4. Idiopathic pulmonary fibrosis (IPF) and active phase
5. Pulmonary hemorrhage (e.g., bronchitis; bronchiectasis; pulmonary thromboembolism; bronchogenic carcinoma; contusion of lung; vasculitis—Wegener granulomatosis, Goodpasture S., lupus erythematosus; aspergilloma; anticoagulation; bleeding diathesis; arteriovenous malformation; DIC; vascular metastases
6. Connective tissue disease (esp. lupus erythematosus; scleroderma)
7. Sarcoidosis
8. Bronchiolitis obliterans with organizing pneumonia (BOOP)
9. Bronchiolitis obliterans
10. Infection
a. Pneumocystis carinii pneumonia
b. Viral (esp. cytomegalovirus in immunocompromised patients)
c. Bacterial
d. Tuberculosis; atypical mycobacterial infection (“tree-in-bud”)


MASS IN A PULMONARY CAVITY (MENISCUS OR [bleep]’S EYE SIGN)

1. Fungus ball (esp. Aspergillus; rarely Cryptococcus; Candida; Coccidioides)
2. Hydatid cyst


BLURRING OF THE HEART BORDER ON PA CHEST FILM

1. Idiopathic
2. Infiltrate or edema in left lingula, right middle lobe, or anterior segment of an upper lobe
3. Mediastinal lesion, anterior (e.g., thymoma; thymic cyst; thymolipoma; teratoma; lymphoma; pericardial cyst; lipoma; mediastinitis; fibrosis)
4. Normal or congested blood vessels (esp. right heart border)
5. Pericardial fat pad
6. Pleural fluid
7. Pleuropericardial adhesion; postinfarction myocardial scar
8. Pneumoconiosis (esp. asbestosis)


TYPE OF PLEURAL FLUID— TRANSUDATE (Protein <>

1. Cirrhosis
2. Fluid overload
3. Heart failure
4. Renal failure; uremia


TYPE OF PLEURAL FLUID—EXUDATE (Protein > 3 g/dl)

1. Lymphoma; leukemia
2. Metastases to pleura (esp. bronchogenic carcinoma)
3. Pneumonia (esp. bacterial); lung abscess
4. Pulmonary thromboembolism
5. Tuberculosis


UNILATERAL ELEVATED HEMIDIAPHRAGM

1. Atelectasis
2. Distended stomach or splenic flexure of colon
3. Eventration
4. Idiopathic; normal variant
5. Inflammatory disease in abdomen (e.g., subphrenic, perinephric, hepatic, or splenic abscess; pancreatitis; cholecystitis; perforated ulcer)
6. Interposition of colon between liver and right hemidiaphragm (Chilaiditi S.)
7. Paralysis (e.g., phrenic nerve palsy or paralysis, esp. from bronchogenic carcinoma; primary or metastatic mediastinal malignancy; extrinsic pressure from intrathoracic goiter or aortic aneurysm; trauma; iatrogenic-surgical transection)
8. Pleural disease (e.g., acute pleurisy; fibrosis; old empyema, hemothorax or pleural tuberculosis; mesothelioma)
9. Postoperative (e.g., lobectomy; pneumonectomy); postpericardiotomy S. (post-CABG)
10. Ruptured spleen or liver (esp. subphrenic hematoma)
11. Scoliosis (on side of concavity)
12. Splinting of diaphragm or guarding from acute process (e.g., fractured rib; chest wall trauma; pulmonary infarct; pneumonia)
13. Subphrenic mass (e.g., enlargement, tumor, cyst, or abscess of liver or spleen; carcinoma of stomach)
14. Trauma to phrenic nerve, thorax, cervical spine, or brachial plexus


EGGSHELL CALCIFICATIONS IN THE CHEST (ESP. MEDIASTINAL LYMPH NODES)

1. Aneurysm of great vessels
2. Idiopathic
3. Silicosis; coal-worker’s pneumoconiosis

DOUBLE-BARREL ESOPHAGUS*

1. Dissecting intramural hematoma or hemorrhage
a. Severe vomiting (e.g., Boerhaave S. with esophageal perforation, or Mallory-Weiss S. with esophageal tear)
b. Trauma
c. Instrumentation (e.g., nasogastric intubation; endoscopy)
d. Ingestion of sharp foreign body
e. Spontaneous (e.g., bleeding diathesis)

* Barium opacification of an intramural dissecting channel separated from the normal esophageal lumen by an intervening radiolucent mucosal stripe.


DUODENAL OBSTRUCTION IN AN INFANT (DOUBLE BUBBLE SIGN)

COMMON
1. Annular pancreas
2. Congenital peritoneal bands (Ladd’s bands)
3. Duodenal atresia or stenosis, esp. with trisomy 21 S. (Down S.)
4. Midgut volvulus with malrotation

UNCOMMON
1. Choledochal cyst
2. Diaphragm or web; intraluminal diverticulum
3. Duplication cyst
4. Intramural hematoma
5. Preduodenal portal vein
6. Retroperitoneal tumor (e.g., teratoma) or lymphadenopathy


SENTINEL LOOP (LOCALIZED DILATATION OF SMALL AND/OR LARGE BOWEL)

1. Acute appendicitis (right lower quadrant)
2. Acute cholecystitis (right upper quadrant)
3. Acute diverticulitis (left lower quadrant)
4. Acute pancreatitis (upper or mid-abdomen)
5. Acute ureteral colic (stone)
6. Infarction or ischemia of bowel
7. “Paralytic ileus”
8. Perforated peptic ulcer (upper abdomen)


“THUMBPRINTING” OF THE GASTROINTESTINAL TRACT (MULTIPLE INTRAMURAL DEFECTS)

1. Crohn’s disease
2. Diverticulitis
3. Ischemic colitis with hemorrhage into bowel wall
4. Ulcerative colitis


B.U.L.L.’S EYE LESION (SOLITARY OR MULTIPLE NODULES IN THE GASTROINTESTINAL TRACT WITH LARGE CENTRAL ULCERATION)

1. Gastrointestinal stromal tumor (esp. leiomyoma; leiomyosarcoma; neurofibroma)
2. Lymphoma
3. Metastatic melanoma
4. Peptic ulcer

STRUCTURES THAT SONOGRAPHICALLY MIMIC THE GALLBLADDER

1. Abscess (esp. near ligamentum teres)
2. Choledochal cyst
3. Dilated cystic duct remnant
4. Fluid-filled duodenal bulb
5. Hepatic cyst
6. Omental cyst
7. Renal cyst


LIVER LESION CHARACTERIZED BY B.U.L.L.’S EYE APPEARANCE

1. Fungus disease (e.g., candidiasis, usually in immunocompromised individual); other opportunistic infections
2. Kaposi sarcoma
3. Lymphoma; leukemia
4. Metastasis
5. Sarcoidosis
6. Septic emboli


DAMPING OF HEPATIC VEIN DOPPLER WAVEFORM (US)

1. Budd-Chiari syndrome
2. Cirrhosis
3. Extrinsic compression of hepatic veins
4. Passive hepatic congestion
5. Various parenchymal abnormalities of liver


ALTERATION IN DENSITY OF THE MESENTERIC FAT ON CT (“Misty Mesentery”)

1. Hemorrhage (e.g., trauma)
2. Inflammation (e.g., Crohn’s disease)
3. Lymphedema
4. Mesenteric edema
5. Neoplasm, e.g., carcinomatosis; mesothelioma (esp. after chemotherapy)
6. Retractile mesenteritis (chronic fibrosing mesenteritis; mesenteric lipodystrophy; panniculitis; Weber- Christian disease)


“PSEUDOKIDNEY” OR “B.U.L.L.’S EYE” SIGN IN THE ABDOMEN (US)

1. Gastroesophageal junction
2. Hypertrophic pyloric stenosis
3. Inflammatory bowel disease with wall thickening (e.g., amebiasis; Crohn’s disease; diverticulitis; Whipple’s disease)
4. Intussusception (multiple concentric rings)
5. Malignant neoplasm with thickening of bowel wall (e.g., carcinoma; lymphoma; leiomyosarcoma; metastasis to serosa)

HYPOTHALAMIC LESIONS ON MRI

1. Ectopic posterior pituitary gland
2. Germinoma
3. Glioma
4. Hamartoma of tuber cinereum
5. Langerhans cell histiocytosis
6. Lymphoma, primary
7. Sarcoidosis; tuberculosis
8. Wernicke’s encephalopathy

CEREBELLOPONTINE ANGLE MASS ON CT OR MRI

1. Acoustic schwannoma (neurinoma)
2. Aneurysm or ectasia of basilar or vertebral artery
3. Epidermoid (congenital cholesteatoma)
4. Lateral extension of adjacent tumor (e.g., pontine glioma; ependymoma or other fourth ventricular tumor; choroid plexus tumor; cerebellar neoplasm {astrocytoma; hemangioblastoma}; chordoma)
5. Meningioma

PERIVENTRICULAR HYPERINTENSE (BRIGHT) LESION ON T2-WEIGHTED MRI

CHILDREN AND YOUNG ADULTS
1. Acute disseminated encephalomyelitis (ADEM) (postviral leukoencephalopathy)
2. Ependymitis granularis (anterior and lateral to frontal horns in normal individuals)
3. Leukodystrophies
a. Adrenoleukodystrophy
b. Alexander’s disease
c. Canavan’s disease
d. Krabbe disease (globoid cell leukodystrophy)
e. Metachromatic leukodystrophy
f. Pelizaeus-Merzbacher disease
4. Migraine
5. Mucopolysaccharidoses
6. Multiple sclerosis
7. Vasculitis (lupus erythematosus; sickle cell disease; Behçet S.)
8. Virchow-Robin spaces in putamen

ELDERLY
1. Ischemia of deep white matter (e.g., ischemic cardiovascular disease; hypertension; smoking)
2. Lacunar infarction

PATIENTS WITH AIDS
1. Lymphoma
2. Progressive multifocal leukoencephalopathy (PML)
3. Subacute white matter encephalitis (esp. due to HIV or cytomegalovirus infection)
4. Toxoplasmosis


AVASCULAR INTRACRANIAL MASS

1. Abscess
2. Contusion
3. Edema
4. Epidural hematoma, hygroma, or empyema
5. Hematoma (intracerebral)
6. Neoplasm (low grade glioma {astrocytoma; oligodendroglioma; metastasis)
7. Subdural hematoma, hygroma, or empyema

ECHOGENIC BRAIN LESIONS ON ULTRASOUND

1. Calcification
2. Hemorrhage (e.g., subependymal)
3. Infarction
4. Normal (choroid plexus; caudothalamic groove)

INCREASED INTRACRANIAL PRESSURE

COMMON
1. Brain abscess
2. Cerebral edema, contusion, hemorrhage, or infarction
3. Hematoma (intracerebral, extradural, subdural); hygroma
4. Hydrocephalus, obstructive
5. Lead encephalopathy
6. Malignant hypertension
7. Meningitis, meningoencephalitis (e.g., tuberculosis; cryptococcosis {torulosis}; toxoplasmosis)
8. Metastatic neoplasm (e.g., bronchogenic carcinoma; neuroblastoma)
9. Primary brain tumor

UNCOMMON
1. Aqueductal stenosis
2. Arnold-Chiari malformation
3. Craniostenosis, severe
4. Dandy-Walker S. (Dandy-Walker malformation)
5. Drug therapy (e.g., tetracycline)
6. Emphysema, severe with cough
7. Hyperthyroidism
8. Hypervitaminosis A
9. Hypoparathyroidism
10. Increased venous pressure
11. Leukemia; lymphoma
12. Meningocele
13. Parasitic disease (e.g., cysticercosis; hydatid disease; paragonimiasis)
14. Pseudotumor cerebri

RADIOLOGIC FEATURES OF INCREASED INTRACRANIAL PRESSURE

1. Increased craniofacial ratio
2. Increased digital markings of calvarium (“hammered silver” appearance)
3. Sellar changes
a. Decalcification of floor and dorsum of sella
b. Pointed anterior clinoid
c. Sellar enlargement
d. Thinning or loss of posterior clinoid
4. Sutural diastases; unusually deep sutural interdigitations
5. Thinning of calvarium