22 Must Sees-2012

22 “Must See” DiagnosticImages for MedicalStudents

All images retain the copyrights of their original authors

Index at end of presentation

AMSER’s “Shortlist”

•AMSER is the national Alliance of Medical StudentEducators in Radiology

•Their National Curriculum for Medical Students,developed by Kitt Shafer, MD and Petra Lewis, MD,contains a “Diagnostic Shortlist” of “must see" images“all students should recognize”

•This is a limited list of diagnoses that AMSER believesall students should be able to recognize, regardless oftheir planned specialty

The Owl

•Wherever you see the owl graphic, thatslide contains a hyperlink to additionalinformation. Click on the underlined linkon that slide

Diagnosis

Can you tell why this patient is short of breath?

Tension pneumothorax

Complete right-sidedpneumothorax

Lung iscompressedagainstmediastinum

Shift of heartand trachea toleft

Tension pneumothorax

Pneumothorax

Post

Ant

With person lying ontheir back, air inpleural space rises totop and displacesnormal lung

Pneumothorax

•To learn more about pneumothorax, goto: Recognizing a Pneumothorax

Hot-link on this page

Diagnosis

This person developed chest pain after vomiting. Why?

Pneumomediastinum from Ruptured Esophagus(Boerhaave's Syndrome)

Streaky, lineardensities dueto air in themediastinum

Boerhaave's SyndromePneumomediastinum – CT scan

Airsurroundingesophagus inmediastinum

Extraluminalcontrast fromperforationalong leftlateral wall ofdistalesophagus

Pneumomediastinum

•To learn more aboutpneumomediastinum, go to:Pneumomediastinum

Hot-link on this page

Diagnosis

Why does this patient have abdominal pain?

Pneumoperitoneum

Air outlinesunder surface oflefthemidiaphragm

Air outlinesunder surface ofrighthemidiaphragm

Air outlines bothsides of the wallof the stomach-asign of free airin the peritonealcavity

Pneumoperitoneum

Pneumoperitoneum - CT

CT scans on 2 different people show a small and large amount of free air in theperitoneal cavity which rises to the highest point (anteriorly with the personlying on their back) and is not contained within bowel

Free air

Pneumoperitoneum

•To learn more aboutpneumoperitoneum, go to: Recognizing Free Air

Hot-link on this page

Diagnosis

57 year-old female with shortness of breath. Why?

Bilateral Pleural Effusions

Meniscus-shaped densityat left base froma pleuraleffusion

Meniscus-shaped densityat right basefrom a pleuraleffusion

Meniscus-shaped densityat right basefrom a pleuraleffusion

Meniscus-shaped densityat left base froma pleuraleffusion

Bilateral Pleural Effusions - CT

Effect of Position - Layering

Supine

Erect

In the supine position, the fluid layers out posteriorly and produces ahaziness, especially near the bases (since the patient is actually semi-recumbent). In the erect position, the fluid falls to the bases.

Pleural Effusion

•To learn more about pleural effusions,go to: Recognizing a Pleural Effusion

Hot-link on this page

Diagnosis

This patient has atrial fibrillation and a heart murmur.What’s the diagnosis?

Size (notnumber) ofvessels at theapex exceedssize of vesselsat the base inthis uprightperson. This iscalled“cephalization.”Normally thevessels at thebase exceed thesize of thevessels at theapex

Pulmonary Venous Hypertension from Mitral Stenosis

Inset of Apex of Lung

Vessels are larger atapex=cephalization

Pulmonary Interstitial Edema

Pulmonary interstitial edema with intersectingKerly A and C lines (red circle)

Pulmonary Alveolar Edema

Bilateral,diffuseairspacedisease moremarkedcentrallythan at theperiphery ofthe lung(“bat-wingappearance”)

Pulmonary Edema

•To learn more about pulmonary edema,go to: Recognizing Congestive Heart Failure

Hot-link on this page

Diagnosis

63 year-old man with chest pain. Why?

Aortic Dissection

Linear lucencyin the contrast-filleddescendingaorta is theintimal flap of anaortic dissection

Aortic Dissection

• Widenedmediastinum

• Left pleural effusion

• Chest pain

Should make you thinkof an aortic dissection

Classification of Dissecting Aneurysms

Stanford classification

• Widened mediastinum

• Left pleural effusion

• Chest pain

Aortic Dissection

•To learn more about aortic dissection,go to: Aortic Dissection

Hot-link on this page

Diagnosis

Why did this 85 year-old haveabrupt onset of abdominal pain?

Aortic rupture

Red arrowspoint to activeextravasation ofcontrast fromthe aorta intotheretroperitoneum

Thrombusinside the lumenof the aorta

Red arrowspoint to activeextravasation ofcontrast fromthe aorta intotheretroperitoneum

Aorta

Ruptured Aortic Aneurysm

Enlargement of abdominal aorta > 3cm

Usually 2 to atherosclerosis

Below renals, above iliacs

About 20-25% rupture

<4cm~10%; >10 cm~60%

Retroperitoneal, usually on left

Into GI tract: massive hemorrhage

Into IVC: rapid cardiac decompensation

Diagnosis

Newborn with tachypnea. Why?

Congenital Absence of the Diaphragm

Left hemithoraxcontainsmultiplelucencies--air inthe lumen ofbowel, nowlocated in thechest

Heart andtrachea aredisplaced toright by bowel inoppositehemithorax

Congenital Absence of DiaphragmImaging Findings

Initially, hemithorax may appear opaquebecause loops are fluid-filled

Paucity of bowel loops beneath diaphragm

Once air swallowing begins, multiplelucencies contained within bowel are seen inchest

Respiratory distress may increase as intestineoccupies more of thorax

Diaphragmatic Rupture

•To learn more about congenitalabsence of the diaphragm anddiaphragmatic rupture, go to: Diseases of the Diaphragm

Hot-link on this page

Diagnosis

36 year-old with acute abdominal pain. Why?

Small Bowel Obstruction

Multiple air-containingand dilated loops ofsmall bowel

No gas in rectosigmoid

Multiple air-fluid levelsin smallbowel

Small Bowel Obstruction

•To learn more about small bowelobstructions, go to: Recognizing Obstruction and Ileus

Hot-link on this page

Diagnosis

83 year-old with distended abdomen.What’s the diagnosis?

Sigmoid Volvulus

Sigmoid twistsaround thispoint

Obstructed,dilated sigmoidhas a “coffee-bean” shape

Cecal Volvulus

Dilated loop inLUQ is cecumwhich hastwisted on itself

Dilated loops ofsmall bowelfrom smallbowelobstruction atileocecal valve

Sigmoid Volvulus – Barium Enema

Sigmoid twistsat this point

Dilated colonproximal tothe volvulus

Rectum

Cecal and Sigmoid volvulus

•To learn more about sigmoid volvulus,go to: Sigmoid volvulus

Hot-link on this page

Diagnosis

74 year-old with change of bowel habits. Why?

Large bowel obstruction – Sigmoid carcinoma

Dilated loops oflarge bowel withabrupt cut-off insigmoid

Barium enemashows annularconstrictingcarcinoma ofsigmoidproducingobstruction

Rectum

Dilated large bowel

Carcinoma of the Colon

•To learn more about carcinoma of thecolon, go to: Carcinoma of the Colon

Hot-link on this page

Diagnosis

Why does this 47 year-old haveincreasing abdominal girth?

Bowelloops aredisplacedcentrallyby asciticfluid

Ascites - CT

Ascites

Ascites islow inattenuation

Massive ascites on CT

Massive ascites (redarrows) in a patientwith metastaticcarcinoma of theovary

Liver

Ascites

Patient’shead

Patient’sFeet

Ascites demonstrated by ultrasound

Echo-free fluidabove liverbeneath righthemidiaphragm

Diagnosis

Misplaced Lines and Tubes

Tip of nasogastric tube (yellow arrow) should lieat least 10cm past the EG junction

Feeding tube (green arrow) enters right lower lobe bronchus, loops onitself then crosses over to LLL bronchus (red arrow).

Tip of central venous catheter coils back on itself in rightbrachiocephalic vein (red arrow).

Tip of endotracheal tube is in right mainstem bronchus (redarrow) leading to atelectasis of the right upper lobe and entireleft lung

Swann-Ganz catheter enters left pulmonary artery (red arrow),then loops back on itself with tip in region of right ventricularoutflow tract (green arrow)

Tip of Swan-Ganz catheter lies too peripherally in rightdescending pulmonary artery (red arrow)

Tip of pleural drainage catheter (thoracotomy drainage tube) liescompletely outside of the left hemithorax (red arrow).

Misplaced lines and tubes

•For more on the proper location of linesand tubes, go to: Tubes and Lines:What, Where and Whoops

Hot-link on this page

Diagnosis

Child brought to Emergency Department with multiple bruises.What is the most likely diagnosis?

Healing ribfractures

Healing fractureof posterior rib(highlysuggestive ofchild abuse)

Child Abuse

Child Abuse

Metaphysealfractures likethis one arecharacteristic ofchild abuse

Metaphysealfractures likethis one arecharacteristic ofchild abuse

Fracture of tibia

Child Abuse

Bilateralsubdural orepiduralhematomas,shown here onMRI, are highlysuspicious forchild abuse

Child Abuse

Child Abuse

•For more on Battered Child Syndrome(child abuse), go to : Child abuse

Hot-link on this page

Diagnosis

72 year-old with slurred speech. Why?

Intraparenchymal hemorrhage

Hemorrhageinto brainstemon non-contrastenhanced CT

Cerebrovascular Accident with Mass effect

Shift of falx toopposite side

Largeintraparenchymalbleed

Midline shift fromhemorrhage andedema

Diagnosis

37 year-old hit in the head with a brick.What’s the diagnosis?

Traumatic intracranial hemorrhageEpidural Hematoma

Crescentic areaof increasedattenuation onnon contrast-enhanced CTwith convexitytoward brain ischaracteristic ofan epiduralhematoma

Traumatic intracranial hemorrhageSubdural hematoma

Crescentic lowattenuationlesion atperiphery ofbrain containinga fluid-fluid level(yellow arrow)from blood

Traumatic intracranial hemorrhageIntraparenchymal hemorrhage

Intraparenchymalhemorrhage

Acutehemorrhage onnon-contrast-enhanced CTof brain

Hemorrhage with blood in lateral ventricles

Blood settlinginto posteriorhorns of lateralventricle

Subarachnoid hemorrhage from ruptured aneurysm

Acute hemorrhage in the basilar cisterns (red arrows) and Sylvian fissures(green arrows) in two patients with ruptured aneurysms

Diagnosis

58 year-old with headache.What’s the diagnosis?

Obstructive hydrocephalus caused by aColloid Cyst of 3rd ventricle

Markedlyenlargedfrontal horns

Colloid Cystobstructingthirdventricle

Choroidplexus(normal)

Hydrocephalus from Choroid Plexus Papilloma

Lateralventricles –anterior andposteriorhorns

Large massrepresents achoroidplexuspapilloma

Hydrocephalus from Cerebral Atrophy

Dilatedlateralventricles –anterior andposteriorhorns

Prominentsulci

Communicating (“Normal Pressure”) Hydrocephalus

Dilated thirdventricle(yellowarrow) andtemporalhorns (redarrow)

Dilated 4thventricle

Diagnosis

58 year-old woman with breast cancer and headache.What is the most likely diagnosis?

Metastatic breast carcinoma

Surroundingedema

Ring-shapedenhancinglesion withconsiderableedemasurrounding it

Shift of falxdue to masseffect of edema

Diagnosis

Two different people who fell injuring neck.What are the diagnoses?

Fracturethroughposteriorelements of C2

Forwarddisplacementof the body ofC2 (red arrows)

Spinolaminarwhite line of C2does not alignwith othervertebral bodies

Fracture of C2 - “Hangman’s Fracture”

Hangman’s Fracture

Most common fracture of C2

Most common cervical spine fracture

Hyperextension/compression fracture

Fractures through the pedicles of C2 withanterior slip of C2 on C3

Not associated with neuro deficit

Locked facets

The inferiorarticular facet ofC5 (red arrow) hasslipped forwardand lies anteriorto the superiorarticular facet ofC6 (green arrow)— a conditionknown as a“locked facet”