Liver ultrasound

Post on 11-Nov-2014

2.915 views 6 download

Tags:

description

 

Transcript of Liver ultrasound

Liver ultrasoundLiver ultrasoundBy By

Dr. Tarek MansourDr. Tarek MansourFaculty of medicine Faculty of medicine Al-Azhar universityAl-Azhar university

Normal liver.Normal liver. Doppler of hepatic vessels.Doppler of hepatic vessels. Diffuse liver diseases pattern.Diffuse liver diseases pattern. Portal hypertension.Portal hypertension. Focal liver masses.Focal liver masses.

Liver techniqueLiver technique Always clear 2-3 Always clear 2-3

cm beyond the cm beyond the margin of any margin of any organ to avoid organ to avoid exophytic or exophytic or adjacent masses.adjacent masses.

Normal liverNormal liver SizeSize ShapeShape EchogenicityEchogenicity EchotextureEchotexture Technique Technique - smooth TGC- smooth TGC - diaphragm- diaphragm - vessel lumen- vessel lumen - clear all - clear all

marginsmargins

Parenchymal organ Parenchymal organ echogenicityechogenicity

Renal medulla < renal cortex < liverRenal medulla < renal cortex < liver Liver < spleenLiver < spleen Liver < pancreas.Liver < pancreas. Pancreas < renal sinus & retro. fatPancreas < renal sinus & retro. fat

Sonographically the Sonographically the vessels seen visible vessels seen visible within the liver within the liver parenchyma are parenchyma are hepatic and portal hepatic and portal veins.veins.

Hepatic arteries and Hepatic arteries and bile ducts not seen bile ducts not seen unless abnormally unless abnormally dilated but seen in dilated but seen in porta hepatis.porta hepatis.

Portal veinsPortal veins Echogenic (bright) wallsEchogenic (bright) walls - used for evaluation - used for evaluation of evaluation of liverof evaluation of liver parenchyma.parenchyma. Enter the liver through Enter the liver through

porta hepatis.porta hepatis. Largest portal vein divide Largest portal vein divide

in the middle of liver.in the middle of liver. More horizontally More horizontally

oriented.oriented. Pass within lobes and Pass within lobes and

segments.segments. Flow into liver.Flow into liver.

Portal veinPortal veinReasons for bright Reasons for bright

wallswalls Portal triadPortal triad -Portal vein-Portal vein -Hepatic artery-Hepatic artery -Bile duct-Bile duct Glisson's capsuleGlisson's capsule Lymphatic nerves.Lymphatic nerves. Connective tissueConnective tissue

Hepatic veinsHepatic veins Imperceptible margins.Imperceptible margins. Enlarge toward the IVC.Enlarge toward the IVC. More vertically More vertically

oriented.oriented. Umbrella configuration.Umbrella configuration. Runs between lobes and Runs between lobes and

segments.segments. Used as anatomic Used as anatomic

divider of the liver.divider of the liver. Flow out the liver Flow out the liver

Transverse liver scanTransverse liver scanAnatomic landmarkAnatomic landmark

Upper: large hepatic Upper: large hepatic veins joint IVCveins joint IVC

Mid: large central Mid: large central portal veins (left higher portal veins (left higher than right).than right).

Lower: Lower: -No large veins.-No large veins. -Falciform ligament-Falciform ligament -Ligamentum teres. -Ligamentum teres.

Ligamentum teresLigamentum teres Obliterated fetal Obliterated fetal

reminant of the reminant of the umbilical vein in the umbilical vein in the fissure for ligamentum fissure for ligamentum teres.teres.

Joins the umbilical Joins the umbilical segment of the left segment of the left portal vein.portal vein.

May recanalize in May recanalize in portal hypertension.portal hypertension.

Not to be mistaken for Not to be mistaken for a mass or calcium.a mass or calcium.

Divides left lobe.Divides left lobe.

Ligamentum venosumLigamentum venosum The obliterated The obliterated

fetal reminant of fetal reminant of ductus venosus.ductus venosus.

Lie within fissure Lie within fissure for ligamentum for ligamentum venosus.venosus.

Does not recanalize Does not recanalize in adults.in adults.

Separates the left Separates the left lobe from caudate lobe from caudate lobe.lobe.

Caudate lobeCaudate lobe Caudate means tail.Caudate means tail. Functionally autonomous segment, Functionally autonomous segment,

spared in liver diseases.spared in liver diseases. Blood supply from RT and LT portal Blood supply from RT and LT portal

vein.vein. Dian direct to IVC.Dian direct to IVC. Pseudomass.Pseudomass.

Enlarged caudate lobeEnlarged caudate lobe Caudate is Caudate is

enlarged when the enlarged when the caudate to right caudate to right lobe ratio is > 0.65lobe ratio is > 0.65

Hepatic and portal veinsHepatic and portal veins Basis of modern lobar Basis of modern lobar

and segmental and segmental anatomy.anatomy.

Hepatic veins drain Hepatic veins drain peripherallyperipherally

-Interlobar, -Interlobar, intersegmental.intersegmental.

-Used as dividers.-Used as dividers. Portal veins feed Portal veins feed

centrally.centrally. -Intralobar, -Intralobar,

intrasegmentalintrasegmental -Used to name -Used to name

segments.segments.

Hepatic veins (anatomic Hepatic veins (anatomic dividers)dividers)

MHV divide the MHV divide the liver into right and liver into right and left lobes.left lobes.

RHV divide the RHV divide the right lobe into right lobe into anterior and anterior and posterior segments.posterior segments.

LHV divide the left LHV divide the left lobe into medial and lobe into medial and lateral segments lateral segments (cranially).(cranially).

Portal vein define Portal vein define segmentssegments

Feed the Feed the segments.segments.

Define the Define the segments.segments.

Name the Name the segments.segments.

Division of main portal Division of main portal veinvein

On coronal scan On coronal scan divides the liver divides the liver into superior and into superior and inferior.inferior.

On axial scan On axial scan divides the liver divides the liver into anterior and into anterior and posterior.posterior.

Anatomic liver segmentsAnatomic liver segmentscaudate lobecaudate lobe Segment ISegment I

Lateral segment left Lateral segment left lobe superiorlobe superior

Segment Segment IIII

Lateral segment left Lateral segment left lobe inferiorlobe inferior

Segment Segment IIIIII

Medial segment left Medial segment left lobelobe

Segment Segment IVIV

Anterior segment Anterior segment right lobe inferiorright lobe inferior

Segment Segment VV

Posterior segment Posterior segment right lobe inferiorright lobe inferior

Segment Segment VIVI

Posterior segment Posterior segment right lobe superiorright lobe superior

Segment Segment VIIVII

Anterior segment Anterior segment right lobe superiorright lobe superior

Segment Segment VIIIVIII

Main portal vein: normal Main portal vein: normal dopplerdoppler

Continuous, forward flow.Continuous, forward flow. Low velocity (15-28 Low velocity (15-28

cm/sec.)cm/sec.) Hepatopetal flow.Hepatopetal flow. Undulating patternUndulating pattern -Respiratory variation-Respiratory variation -Increase flow on -Increase flow on

inspiration.inspiration. May reflect cardiac May reflect cardiac

variation.variation. Slightly turbulent.Slightly turbulent. Location between two Location between two

capillary beds (mesenteric capillary beds (mesenteric & hepatic).& hepatic).

Normal portal venous flow Normal portal venous flow direction and waveform. direction and waveform. Drawing at top illustrates Drawing at top illustrates that the direction of flow in that the direction of flow in normal portal veins is normal portal veins is antegrade, or hepatopetal, antegrade, or hepatopetal, which corresponds to a which corresponds to a waveform above the baseline waveform above the baseline at spectral Doppler US. at spectral Doppler US. Normal phasicity may range Normal phasicity may range from low (bottom left) to high from low (bottom left) to high (bottom right). Abnormally (bottom right). Abnormally low phasicity results in a low phasicity results in a nonphasic waveform, nonphasic waveform, whereas abnormally high whereas abnormally high phasicity results in a pulsatile phasicity results in a pulsatile waveform. The PI is used to waveform. The PI is used to quantify pulsatility. Normal quantify pulsatility. Normal phasicity results in a PI phasicity results in a PI greater than 0.5. greater than 0.5.

Main portal vein: abnormal Main portal vein: abnormal dopplerdoppler

Pulsatile flow is abnormalPulsatile flow is abnormal - May resemble HV - May resemble HV

pulsatility.pulsatility. - Increase right heart - Increase right heart

pressure.pressure. - Transmitted pressure - Transmitted pressure

through intrahepatic through intrahepatic sinusoids.sinusoids.

- Tricuspid - Tricuspid regurgitation.regurgitation.

- Moderate to sever right - Moderate to sever right heart failure, pericarditis.heart failure, pericarditis.

Exception: child, young Exception: child, young persons.persons.

Spectral Doppler US Spectral Doppler US image shows a image shows a pulsatile waveform pulsatile waveform with flow reversal in with flow reversal in the right portal vein. the right portal vein. The waveform may be The waveform may be systematically systematically characterized as characterized as predominantly predominantly antegrade, pulsatile, antegrade, pulsatile, biphasic-bidirectional, biphasic-bidirectional, and di-inflectional. and di-inflectional.

Slow portal venous flow. Slow portal venous flow. Spectral Doppler US image Spectral Doppler US image shows slow flow in the main shows slow flow in the main portal vein. Slow portal portal vein. Slow portal venous flow is a venous flow is a consequence of portal consequence of portal hypertension. In this case, hypertension. In this case, the peak velocity is 9.0 the peak velocity is 9.0 cm/sec, which is well below cm/sec, which is well below the lower limit of normal the lower limit of normal (16–40 cm/sec). Although (16–40 cm/sec). Although portal hypertension may portal hypertension may cause a pulsatile-appearing cause a pulsatile-appearing waveform as seen in this waveform as seen in this case, the slow flow helps case, the slow flow helps differentiate this condition differentiate this condition from hyperpulsatile high-from hyperpulsatile high-velocity states such as CHF velocity states such as CHF and tricuspid regurgitation. and tricuspid regurgitation.

Normal and abnormal portal Normal and abnormal portal venous phasicity. Images venous phasicity. Images show a spectrum of show a spectrum of increasing pulsatility increasing pulsatility (bottom to top). Note that (bottom to top). Note that increasing pulsatility increasing pulsatility corresponds to a decrease corresponds to a decrease in the calculated PI. in the calculated PI. Although normal phasicity Although normal phasicity ranges widely in the portal ranges widely in the portal veins, the PI should be veins, the PI should be greater than 0.5 (middle greater than 0.5 (middle and bottom). When the PI is and bottom). When the PI is less than 0.5 (top), the less than 0.5 (top), the waveform may be called waveform may be called pulsatile; this is an pulsatile; this is an abnormal finding. abnormal finding.

Hepatofugal portal venous Hepatofugal portal venous flow. Spectral Doppler US flow. Spectral Doppler US image shows retrograde image shows retrograde (hepatofugal) flow in the (hepatofugal) flow in the main portal vein, a finding main portal vein, a finding that appears blue on the that appears blue on the color Doppler US image color Doppler US image and is displayed below the and is displayed below the baseline on the spectral baseline on the spectral waveform. Hepatofugal waveform. Hepatofugal flow is due to severe flow is due to severe portal hypertension from portal hypertension from any cause. any cause.

Hepatic artery: normal Hepatic artery: normal dopplerdoppler

Rapid systolic Rapid systolic accelerationacceleration

Continuous forward Continuous forward flow throughout flow throughout cardiac cyclecardiac cycle

- Low impedance.- Low impedance. Same direction as Same direction as

MPV.MPV. RI = 0.5-0.7RI = 0.5-0.7

Schematics show a Schematics show a spectrum of increasing spectrum of increasing hepatic arterial resistance hepatic arterial resistance (bottom to top). The (bottom to top). The hepatic artery normally hepatic artery normally has low resistance (RI = has low resistance (RI = 0.55–0.7) (middle). 0.55–0.7) (middle). Resistance below this Resistance below this range (bottom) is range (bottom) is abnormal. Similarly, any abnormal. Similarly, any resistance above this resistance above this range (top) may also be range (top) may also be abnormal. High resistance abnormal. High resistance is less specific for disease is less specific for disease than is low resistance. than is low resistance.

Hepatic veins: normal Hepatic veins: normal dopplerdoppler

Toward IVC and Toward IVC and heart.heart.

Away from Away from transducer (blue).transducer (blue).

Characteristic Characteristic pulsatile flow.pulsatile flow.

Diagram illustrates normal Diagram illustrates normal hepatic venous flow direction hepatic venous flow direction and waveform. The direction of and waveform. The direction of normal flow is predominantly normal flow is predominantly antegrade, which corresponds antegrade, which corresponds to a waveform that is mostly to a waveform that is mostly below the baseline at spectral below the baseline at spectral Doppler US. The term triphasic, Doppler US. The term triphasic, which refers to the which refers to the aa, , SS, and , and D D inflection points, is commonly inflection points, is commonly used to describe the shape of used to describe the shape of this waveform; according to this waveform; according to D.A.M., however, this term is a D.A.M., however, this term is a misnomer, and the term misnomer, and the term tetrainflectional tetrainflectional is more is more accurate, since it includes the accurate, since it includes the v v wave and avoids inaccurate wave and avoids inaccurate phase quantification. Normal phase quantification. Normal hepatic venous waveforms may hepatic venous waveforms may be biphasic (bottom left) or be biphasic (bottom left) or tetraphasic (bottom right). tetraphasic (bottom right).

Hepatic veins: normal Hepatic veins: normal dopplerdoppler

Reflects respiratory Reflects respiratory phases.phases.

Reflects variations in Reflects variations in central venous pressure central venous pressure transmitted from RV.transmitted from RV.

Reflect compliance of Reflect compliance of liver parenchyma.liver parenchyma.

Triphasic pattern.Triphasic pattern. Deep respiration or Deep respiration or

valsalva reduce valsalva reduce pulsatility of wave form pulsatility of wave form in normals.in normals.

Hepatic veins: abnormal Hepatic veins: abnormal dopplerdoppler

Non triphasic flowNon triphasic flow - Elevated right heart - Elevated right heart

pressure.pressure. Decrease pulsatility or Decrease pulsatility or

amplitude of phasic amplitude of phasic oscillation.oscillation.

- Loss or reversed - Loss or reversed phase.phase.

Monophasic abnormal.Monophasic abnormal. - Flattened wave - Flattened wave

form.form. - Resemble PV flow.- Resemble PV flow. - Stiff, non compliant - Stiff, non compliant

liver.liver.

Decreased hepatic venous Decreased hepatic venous phasicity. Diagrams illustrate phasicity. Diagrams illustrate varying degrees of severity of varying degrees of severity of decreased phasicity in the decreased phasicity in the hepatic vein. Farrant and hepatic vein. Farrant and Meire (5) first described a Meire (5) first described a subjective scale for quantifying subjective scale for quantifying abnormally decreased abnormally decreased phasicity in the hepatic veins, phasicity in the hepatic veins, a finding that is most a finding that is most commonly seen in cirrhosis. commonly seen in cirrhosis. The key to understanding this The key to understanding this scale lies in observing the scale lies in observing the position of the position of the a a wave relative wave relative to the baseline and peak to the baseline and peak negative negative S S wave excursion. As wave excursion. As the distance between the the distance between the a a wave and peak negative wave and peak negative excursion decreases, phasicity excursion decreases, phasicity is more severely decreased. is more severely decreased.

Sonographic liver Sonographic liver patternpattern

NormalNormal CentrilobularCentrilobular Fatty-fibroticFatty-fibrotic

Centri-lobular patternCentri-lobular pattern Decrease echogenicity of Decrease echogenicity of

liver parenchyma.liver parenchyma. Starry night appearance.Starry night appearance. Increase visualization of Increase visualization of

PV wallPV wall - Increased brightness.- Increased brightness. - Increased number.- Increased number. Causes: acute hepatitis, Causes: acute hepatitis,

acute RT side HF, acute RT side HF, leukemia/lymphoma, toxic leukemia/lymphoma, toxic shock, 2% of normal.shock, 2% of normal.

Fulminant hepatic Fulminant hepatic failurefailure

Liver necrosisLiver necrosis Starry night Starry night

appearance (acute, appearance (acute, edema, necrosis).edema, necrosis).

Hyperechoic areas Hyperechoic areas (normal or (normal or regenerated).regenerated).

Fatty fibrotic patternFatty fibrotic pattern Increased echogenicity of Increased echogenicity of

liver parenchyma.liver parenchyma. Decreased definitions of Decreased definitions of

PV walls.PV walls. EchotextureEchotexture - Homogeneous (fine)- Homogeneous (fine) - Heterogeneous - Heterogeneous

(coarse).(coarse). Posterior sound Posterior sound

attenuation.attenuation. Causes: fatty infiltration, Causes: fatty infiltration,

chronic hepatitis, chronic hepatitis, cirrhosis, acute alcoholic cirrhosis, acute alcoholic hepatitis.hepatitis.

Fatty fibrotic pattern Fatty fibrotic pattern EchotextureEchotexture

homogeneoushomogeneous heterogeneousheterogeneous

Fatty liverFatty liver Posterior sound Posterior sound

attenuation.attenuation. Enlarged liver.Enlarged liver. Tend to have fine Tend to have fine

homogeneous homogeneous echotexture.echotexture.

Focal fatty liver changesFocal fatty liver changes Focal fatty liver Focal fatty liver

infiltration.infiltration. Focal fatty sparingFocal fatty sparing

Liver cirrhosisLiver cirrhosis Fatty fibrotic patternFatty fibrotic pattern - Heterogeneous - Heterogeneous

texture (coarse).texture (coarse). - Almost no posterior - Almost no posterior

attenuation.attenuation. Shrunken liver.Shrunken liver. Nodular surface.Nodular surface. Elevated caudate to Elevated caudate to

right lobe ratio (> 0.73 right lobe ratio (> 0.73 has 99% specificity for has 99% specificity for cirrhosis).cirrhosis).

Liver cirrhosisLiver cirrhosis Accounts for > 90% of Accounts for > 90% of

all portal all portal hypertension.hypertension.

Distorted liver Distorted liver architecture.architecture.

- Fibrosis.- Fibrosis. - Regenerating - Regenerating

nodules.nodules. - Distorted vascular - Distorted vascular

channelschannels

Portal hypertensionPortal hypertension Increase hepatic Increase hepatic

resistance.resistance. Increase portal Increase portal

venous pressure.venous pressure. Eventually decrease Eventually decrease

portal flow.portal flow. Reversed portal flow Reversed portal flow

prognostication for prognostication for risk of hemorrhage.risk of hemorrhage.

Portal hypertensionPortal hypertensionSonographic signsSonographic signs

Ascites.Ascites. Dilated MPV, SV, Dilated MPV, SV,

SMV.SMV. Collateral.Collateral. Splenomegaly.Splenomegaly. Various doppler Various doppler

findings.findings.

Collateral veinsCollateral veins Gastroesophageal.Gastroesophageal. Coronary.Coronary. Umbilical.Umbilical. Gastrosplenic.Gastrosplenic. Splenorenal / Splenorenal /

gastrorenal.gastrorenal. Perisplenic.Perisplenic. Intestinal (rectum).Intestinal (rectum). Retroperitoneal.Retroperitoneal.

Portal hypertensionPortal hypertensioncollateral vesselscollateral vessels

Doppler in portal Doppler in portal hypertensionhypertension

Portal vein:Portal vein: - Loss or respiratory - Loss or respiratory

variation.variation. - Decrease velocity of MPV.- Decrease velocity of MPV. - Hepatofugal (reversed) - Hepatofugal (reversed)

flow.flow. Hepatic veins:Hepatic veins: - Loss of normal pulsatility.- Loss of normal pulsatility. - Non triphasic flow.- Non triphasic flow. - Flattened wave.- Flattened wave. Hepatic arteries:Hepatic arteries: - Enlarged hepatic - Enlarged hepatic

arteries.arteries.

Focal liver massesFocal liver masses US is excellent in detecting focal liver lesions.US is excellent in detecting focal liver lesions. US is specific for liver cysts > 1 cm.US is specific for liver cysts > 1 cm. Not good in differentiating among pathologic Not good in differentiating among pathologic

entities.entities. No good in distinguishing between benign No good in distinguishing between benign

and malignant lesions.and malignant lesions. Triphasic study of the lesions by CT and MRI Triphasic study of the lesions by CT and MRI

are excellent.are excellent. US is very helpful in diagnosis, follow up and US is very helpful in diagnosis, follow up and

guidance biopsy.guidance biopsy.

Choledochal cystsCholedochal cysts

Complex cystic lesions.Complex cystic lesions. Hemorrhagic cyst.Hemorrhagic cyst. Infected cyst.Infected cyst. HematomaHematoma Abscess.Abscess. Biloma/ seroma.Biloma/ seroma. Biliary Biliary

cystadenoma.cystadenoma. Cystic or necrotic Cystic or necrotic

malignant lesion.malignant lesion.

Liver abscessLiver abscessDifficult in diagnosis.Difficult in diagnosis.

Hypoechoic liver massesHypoechoic liver massesBenign.Benign. Abscess.Abscess. Adenoma.Adenoma. Focal nodular Focal nodular

hyperplasia.hyperplasia. Hemangioma.Hemangioma. Microabscesses.Microabscesses. Focal fatty sparing.Focal fatty sparing.

Malignant.Malignant. Metastases.Metastases. Hepatocellular Hepatocellular

carcinoma.carcinoma. Lymphoma.Lymphoma.

Hyperechoic liver massesHyperechoic liver massesBenign.Benign. Hemangioma.Hemangioma. Abscess.Abscess. Adenoma.Adenoma. Focal nodular Focal nodular

hyperplasia.hyperplasia. Hemorrhagic cyst.Hemorrhagic cyst. Focal fat infiltrate.Focal fat infiltrate.

Malignant.Malignant. Metastases.Metastases. Hepatocellular Hepatocellular

carcinoma.carcinoma. Lymphoma.Lymphoma.

Characteristic lesionsCharacteristic lesions Focal nodular Focal nodular

hyperplasiahyperplasia Hemangioma Hemangioma

Characteristic lesionsCharacteristic lesions Echinococcous cyst Echinococcous cyst

Complication of Complication of metastases.metastases.

Biliary obstruction.Biliary obstruction. Vascular invasion Vascular invasion

(portal (portal thrombosis).thrombosis).

Necrosis.Necrosis. Hemorrhage.Hemorrhage. Infection.Infection.

Thank youThank you