Liver and Biliary System PDF

THE HONG KONG POLYTECHNIC UNIVERSITY Liver and Biliary System Dr. Michael Ying Department of Health Technology and Informatics The Hong Kong Polytechnic University addit...

THE HONG KONG POLYTECHNIC UNIVERSITY Liver and Biliary System Dr. Michael Ying Department of Health Technology and Informatics The Hong Kong Polytechnic University additional study: https://www.jss.org/english/standard/abdominal.html THE HONG KONG POLYTECHNIC UNIVERSITY Liver  THE HONG KONG POLYTECHNIC UNIVERSITY Largest organ in the human body. entirelneregfaty _partǐiilysts Frequently involved in systemic and local diseases, ultrasound examination is often requested to assess 1 hepatic abnormalities. Yoninvesne hepctihs B carrier lenbevepect ef retgular briskfactor of 器ne Jane Hit sclerosis mcnneruk nonzonn7ng but MRI takessible  THE HONG KONG POLYTECHNIC UNIVERSITY Scanning technique and patient preparation assess Pǎntiitmcntrei easier Best examined with real-time ultrasound. lowfveq goodbecmperetre power Ilargestorgenns liver lt clear 3.5 MHz transducer is usually used. 5 MHz transducer can be used for thin / paediatric patients. tpenetrctuporeroli planbeadjusted Betǎǎoiii然 Multi-frequency transducer, varies from 2 to 8 MHz, can be used depending on the image resolution and beam penetration (patient’s size & structure examined). which one is moveimportant under the sitea THE HONG KONG POLYTECHNIC UNIVERSITY betǐdǎiiǎiǎi deepertissue canheseen Multi-frequency transducer. (Left) At 2.7 MHz the wires are poorly resolved and the background ‘texture’ of the test phantom appears coarse. (Right) The same transducer is switched to 5.1 MHz. Without changing any other scan settings, the wires are now resolved and the background texture appears finer. However, signals from the far field are weaker due to the lack of beam penetration.  THE HONG KONG POLYTECHNIC UNIVERSITY nbetmnstrcte m'ateenmrhb.in in thegel bladder gǎgii It is ideal to have drink rater 6 hours of patient fasting. fattyfood1Milli 0eniimnèiiiiiiennuǚ器 品 点点 Patient’s positioning: supine and right anterior oblique uǐǎiniiǎiiiiǚiiǎnn 器器 点 Scan planes: longitudinal, transverse, subcostal and intercostal scans m ni品 3_yiiigen.gs 品1 oh scare Most patient’s liver is tucked beneath the rib cage, herwill dropto ltl ultrasound scan with the patient in full arrested 然 t.in inspiration allows better visualization of the liver.  THE HONG KONG POLYTECHNIC UNIVERSITY Anatomy of liver Unlike CT and MRI, ultrasound scan planes / images vary with the position of the transducer. sianpleneD It is necessary to understand the segmental anatomy of the liver so that any space occupying lesion can be correctly localized.  THE HONG KONG POLYTECHNIC UNIVERSITY Functionally, the liver can be divided into three lobes: – Right lobe – Left lobe – Caudate lobe After birth, the umbilical vein obliterates due to the changes in pressure. The remnant of the umbilical vein forms a brous cord, the ligamentum teres that runs in the free edge of the falciform ligament THE HONG KONG POLYTECHNIC UNIVERSITY The right and left lobes of the liver can be separated by the main lobar fissure which passes through the 1 gall bladder and the IVC ǔnginaryhne THE HONG KONG POLYTECHNIC UNIVERSITY turn tucnsduitrLAR lnituan.ci The caudate lobe is separated from the left lobe by the fissure for 0 0 the ligamentum venosum. The IVC is posterior to the caudate lobe.  THE HONG KONG POLYTECHNIC UNIVERSITY The right lobe of the liver can be further divided into: – Anterior segment – Posterior segment The left lobe of the liver can be further divided into: – Medial segment – Lateral segment The hepatic veins are useful structures to differentiate the different hepatic segments. THE HONG KONG POLYTECHNIC UNIVERSITY Subcostal oblique The hepatic veins are interlobar and R intersegmental u medial separating the lobes 遮 and segments. postenrr echogenrc line diaphuagm  THE HONG KONG POLYTECHNIC UNIVERSITY Since ultrasound allow evaluation of liver anatomy in multiple image planes, operator can localize a lesion to a given liver segment for surgical planning. the eight segment... Couinaud’s anatomy is the universal nomenclature for liver lesion localization. portal vein us hepatnivein Lprevnousl It is based on portal segments. It is of both functional and pathologic importance.  THE HONG KONG POLYTECHNIC UNIVERSITY Each segment has its own arterial, portal venous and hepatic venous blood supply, lympatics and biliary drainage. Therefore, surgeon may resect a segment of a liver lobe, providing the vascular supply to the remaining lobe is still intact. THE HONG KONG POLYTECHNIC UNIVERSITY Seg. 1 – Caudtate lobe Seg. 2 – Lat seg. LL (sup.) Seg. 3 – Lat seg. LL (inf.) Seg. 4 – Med seg. LL Seg. 5 – Ant seg. RL (inf.) Seg. 6 – Post. seg. RL (inf.) Seg. 7 – Post. seg. RL (sup.) RPV LPV Seg. 8 – Ant. seg. RL (sup.) THE HONG KONG POLYTECHNIC UNIVERSITY subcostal oblique Segments 2-4: Recumbent H of the left portal venous bifurcation. THE HONG KONG POLYTECHNIC UNIVERSITY Segments 5-8: Bifurcation of the right portal vein.  THE HONG KONG POLYTECHNIC UNIVERSITY Normal size of the liver An accurate assessment of liver size is difficult with ultrasound because of the limited field of view. hmntedby size ttrensduier panoramictechnique 拉 連起 跲 Extended field of view ultrasound may be useful. overianehmntctimofhmntedfiiid.it 圈 The mean longitudinal diameter of the liver measured along the mid-clavicular line is 10.5 ± 1.5 cm.  THE HONG KONG POLYTECHNIC UNIVERSITY The liver size increases with height and body surface area, but decreases with age. Riedel’s lobe of the liver is an anatomical variation. It is a tongue-like extension of the inferior part of the right lobe of the liver. Usually found in asthenic women. rengnhnt THE HONG KONG POLYTECHNIC UNIVERSITY Lateralview ARview Rt le Lt Riedel usually lowerlobe ___ ˋ Rnedel 愁 等 R.lndne.jo egonn kidney longitudinal  THE HONG KONG POLYTECHNIC UNIVERSITY hrighness Normal liver echogenicity The echogeninty is uniform The normal liver is homogeneous. c以 heterogenous.inof uniform Hyperechoic when compared to the normal renal cortex. Hypoechoic when compared to the spleen. iiièiskndny THE HONG KONG POLYTECHNIC UNIVERSITY Normal liver echogenicity: The liver is more echogenic than the renal cortex. nnig Covtex THE HONG KONG POLYTECHNIC UNIVERSITY Normal liver echogenicity: The liver is less iver echogenic than the spleen spleen. Many thin women whose left lobe of the liver may wrap around the spleen.  THE HONG KONG POLYTECHNIC UNIVERSITY Pathology of the liver Benign focal liver lesions jloiahie Malignant focal liver lesions Diffuse liver diseases ysystimetic THE HONG KONG POLYTECHNIC UNIVERSITY Benign focal liver lesions  THE HONG KONG POLYTECHNIC UNIVERSITY Liver cyst (Simple cyst) One of the most commonly seen liver lesions. Can be congenital (from abnormal development of a biliary radicle) or acquired (from previous trauma or infection). niinnhngǎaǎ Occur in about 2.5% of the general population. inǎii 品 Increased to 7% in the population > 80 years old. older  THE HONG KONG POLYTECHNIC UNIVERSITY Sonographically, simple liver cysts are: – anechoic no eiho – well-defined wall sharp well – posterior enhancement no doppler ow bcs no vessel usually more frequently happen at R lobe THE HONG KONG POLYTECHNIC UNIVERSITY In her Polycystic liver  THE HONG KONG POLYTECHNIC UNIVERSITY Occasionally, patient may develop pain and fever secondary to cyst haemorrhage or infection. For infected or haemorrhagic cysts: trenmccausing – contain internal echoes – with septations lgrls Yini.lu点gontocya – thickened wall fechm esp.in – may appear as a solid mass more echos THE HONG KONG POLYTECHNIC UNIVERSITY Liver cyst complicated by acute haemorrhage. hemorrhgu cysu lecho brightness THE HONG KONG POLYTECHNIC UNIVERSITY A large, infected liver cyst with internal echoes.  THE HONG KONG POLYTECHNIC UNIVERSITY Hydatid cyst Associated with a parasite, Echinococcus granulosus The parasite spreads via the bloodstream to the liver. It then lodges in the liver causing an inflammatory reaction. 㠭 Honeycomb or cartwheel appearance. Calcification around a cyst is usually associated with an old, inactive hydatid lesion. THE HONG KONG POLYTECHNIC UNIVERSITY 0 00 cartwheel smallerǎmpsntiytsurmdy Hydatid cyst demonstrating honeycomb surrounding daughter cysts.  THE HONG KONG POLYTECHNIC UNIVERSITY Liver abscess Patients present with fever, right upper quadrant pain and vomiting. 壞死 nirosns deeddnde Ultrasound appearance can be similar to a necrotic tumour or haematoma.  THE HONG KONG POLYTECHNIC UNIVERSITY Liver abscesses may show a variety of ultrasound features. Their internal appearances vary considerably. Appear homogeneous (due to presence of pus). As it __ progresses, the fluid content may become apparent, and show debris within it (becomes heterogeneous in __ echopattern).  THE HONG KONG POLYTECHNIC UNIVERSITY Demonstrate posterior enhancement as they are fluid- filled. The margins of an abscess are usually irregular, ill- defined and frequently thickened. inflammatory re  THE HONG KONG POLYTECHNIC UNIVERSITY di Yr mgdunaf echogennc ring A liver abscess which is Gas may be produced within the abscess heterogeneous in echopattern which obscures the visualization of the and has ill-defined borders. internal architecture of the lesion. lsngperdhypo Lconmmzbacterncenntgac  THE HONG KONG POLYTECHNIC UNIVERSITY Benign neoplasms Haemangioma: the most common benign hepatic neoplasm Echogenic mass (mostly), but can be atypical hypoechoic or with mixed echogenicity. hyperthypo toform a mess p Highly vascular. Composed of tiny network of blood vessels. Since the blood within the haemangioma is very slow-flowing, it is usually not possible to demonstrate flow with xcolour or Xpower Doppler and the lesions appear avascular on ultrasound. May be solitary or multiple. b no signel in iolur doppler  THE HONG KONG POLYTECHNIC UNIVERSITY i ohyperetm Ohpn Lonultnpk benyhandmehgnanl sharesome I X differentiate us feetnre by only know 75 lesimsothenedi.lt  THE HONG KONG POLYTECHNIC UNIVERSITY lisoeihonc subtle wntimnreninyuiscntreit Focal nodular hyperplasia , FNH : the 2nd most common benign hepatic neoplasm This benign neoplasm is made up of a proliferation of liver cells with hepatocytes, Kupffer cells and biliary and fibrous elements. make a liver To Subtle. Variation of liver contour is the key to identify this kind of masses. May displace normal blood vessels within the parenchyma. Appears as a homogeneous, isoechoic mass. Tends to affect the caudate lobe. THE HONG KONG POLYTECHNIC UNIVERSITY longitudinal tranverse tl mm FNH NH ˋ 01st normal appearance THE HONG KONG POLYTECHNIC UNIVERSITY Focal nodular hyperplasia. Ltgiüiqiiii Subtle, isoechoic mass with abnormal liver contour. Note the hypoechoic scar within the mass. Occasionally, the 1 be hyperechic. scar may depend on composition and compared to liver background Rank of echogenicity: Calci cations Bone Fat Fibrous Tissue Muscle Liver Tissue Fluid (Anechoic) Air/Gas THE HONG KONG POLYTECHNIC UNIVERSITY hgpotcha.scan Focal nodular hyperplasia. tdcnt Subtle, isoechoic mass with abnormal liver contour. Note the hypoechoic scar within the mass. Occasionally, the scar may be hyperechic. THE HONG KONG POLYTECHNIC UNIVERSITY Malignant focal liver lesions  THE HONG KONG POLYTECHNIC UNIVERSITY Hepatocellular carcinoma (HCC) One of the most common malignant tumours. In the West, alcoholic cirrhosis is the most common condition predisposing HCC. In Asia, chronic hepatitis B and C infection account for the high incidence of HCC. On ultrasound, HCC can be hyperechoic or hypoechoic. THE HONG KONG POLYTECHNIC UNIVERSITY bhksmouermodetitiest see hyper nypo ineten LO hpeve.hn f THE HONG KONG POLYTECHNIC UNIVERSITY Hepatocellular carcinoma. GS ultrasound shows a slightly hyperechoic mass with a hypoechoic rim. THE HONG KONG POLYTECHNIC UNIVERSITY Hepatocellular carcinoma. surrumdy Colour Doppler ultrasound shows a peripheral afferent peripheral 0 mass artery (towards the mass), neovascularization. Ghemnial stimulated by mats THE HONG KONG POLYTECHNIC UNIVERSITY Hepatocellular carcinoma. Colour Doppler ultrasound shows the efferent vein (away O from the mass), which is also in the periphery of the mass.  THE HONG KONG POLYTECHNIC UNIVERSITY Liver metastases The liver is one of the most common sites to have metastases. In the United States, liver metastases is up to 20 times more common than HCC. ev CAlolwiveinfm Idvcnn prunarytumorportelveinnl7 frm colon blood The ultrasound appearance of liver metastases is extremely variable. When compared with normal surrounding liver parenchyma, metastases may be hyperechoic, hypoechoic, isoechoic or of mixed pattern.  THE HONG KONG POLYTECHNIC UNIVERSITY hypo oteget.amy Cents hyper hypoeihon rim hgp illdefined ohypo Cheteni THE HONG KONG POLYTECHNIC UNIVERSITY Ěienghkelyneectesn muiiih it there are ntpmrimry cancer bull eyes (not blue), same with target sign, usually occur at intestinal intussusception Bheege hypercentre hyporim multiple hypo lesun THE HONG KONG POLYTECHNIC UNIVERSITY Diffuse liver diseases  THE HONG KONG POLYTECHNIC UNIVERSITY Hepatitis Acute viral hepatitis may be caused by one of several viruses: A, B, C, D or E. The viruses which cause hepatitis B, C and D may also go on to chronic disease and predispose the liver to HCC in the later stages. t A unclean much seafood food too Most patients with acute hepatitis recover completely, but hepatitis B, C and D may go on to develop chronic hepatitis.  THE HONG KONG POLYTECHNIC UNIVERSITY Hepatitis Acute hepatitis. thick Prominent thick echogenic echafenebands surrounding the portal band veins, referred to as “periportal pouunlo_ cuffing”. Diffusely decreased echogenicity of liver parenchyma.  THE HONG KONG POLYTECHNIC UNIVERSITY Hepatitis Acute hepatitis. Prominent thick echogenic bands surrounding the portal veins, referred to as “periportal cuffing”. Diffusely decreased echogenicity of liver parenchyma. dbeame 7So orhypo to the Venelcwtex  THE HONG KONG POLYTECHNIC UNIVERSITY main hepahavteryienteryhuer br prominent after enleriso smellto see Hepatitis hepehevems seeechyenicwell usuclly seen in 9V.to o Acute hepatitis. Hypoechoic liver when compared with right kidney. of masbehm Liver is mildly enlarged and 0 has prominent portal tracts. hypoechow is ladneg THE HONG KONG POLYTECHNIC UNIVERSITY Thickening of the gall bladder wall is the associated finding of acute hepatitis. fhikuessx seen usually well THE HONG KONG POLYTECHNIC UNIVERSITY Chronic hepatitis. In mild condition, liver appears slightly hypoechoic when compared with normal renal cortex. THE HONG KONG POLYTECHNIC UNIVERSITY mflemmetm nnfechn Prolonged Chronic hepatitis. Chronic hepatitis itibruns demonstrates a coarse- textured, heterogeneous liver.. 0  THE HONG KONG POLYTECHNIC UNIVERSITY Fatty infiltration benyn Fatty infiltration (steatosis) is an acquired metabolic disorder. It 1 is reversible in many circumstances. FattyTtsegy exercise stop medna infiltration is the process of accumulation of fat within the hepatic cells may be either focal or diffuse. even locahse mehcchm It is related to various conditions such as alcoholism, obesity and diabetes, it is associated with any process which alters liver metabolism.  THE HONG KONG POLYTECHNIC UNIVERSITY Fatty infiltration The acoustic properties of fat differ from those of normal liver tissue. Therefore, fatty liver appears hyperechoic because the fat globules provide interfaces, which are highly reflective, to reflect the ultrasound beam. untel ultrasound The level of echogenicity is associated with the level of fat deposition. Immlnferfaee α The difference in echogenicity between the liver and right renal parenchyma is increased. T more hyper  THE HONG KONG POLYTECHNIC UNIVERSITY Fatty infiltration The attenuation of fat is greater than that of normal liver tissue, and this has the effect of reduced penetration in the far field. In severe cases of fatty infiltration, most of the ultrasound is reflected back to the transducer in the first few centimetres, creating a highly echogenic near-field band through which the ultrasound is unable to penetrate. see far field THE HONG KONG POLYTECHNIC UNIVERSITY band echofennly hvr Thyperechozc renal THE HONG KONG POLYTECHNIC UNIVERSITY Diffuse fatty infiltration bright Moderate with beam attenuation Rechogennc too much refleolm farheld THE HONG KONG POLYTECHNIC UNIVERSITY Diffuse fatty infiltration. Echogenic near field with reduced beam penetration in the far field. THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty infiltration Onlypereothver is echageml a THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty infiltration. Echogenic area anterior to the portal vein, the common location to have focal fatty o infiltration. THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty infiltration. Echogenic area anterior to the portal vein, the common location to have focal fatty infiltration. misinterpreted byshape as mass THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty infiltration. Irregular area of hyperechogenicity in the right lobe of the liver. o THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty sparing in the caudate lobe. deposit part of it x LL large parthave deposit IU THE HONG KONG POLYTECHNIC UNIVERSITY Focal fatty sparing mimicking a hypoechoic mass. mare 0 weaker blood supply at pertculw creel to check Contrast enhanced US or y 7  THE HONG KONG POLYTECHNIC UNIVERSITY Common sites for focal fatty sparing – Anterior to portal vein at porta hepatis 3main vessels i GB and liver wall between hecetnarlery – Gall bladder fossa enlerng liver – Liver margins Common site for focal fatty infiltration Anterior to portal vein at porta hepatis oo – also centrilobular is more likely  THE HONG KONG POLYTECHNIC UNIVERSITY Classification of diffuse steatosis Mild – Minimal diffuse increase in hepatic echogenicity Moderate echofenncryofhver – Moderate diffuse increase in hepatic echogenicityeihogenunulofvessetluem – as Slightly decreased visualization of intrahepatic vessels and diaphragm Severe Cantvestdecreese – Marked increase in echogenicity – Poor penetration of the posterior liver – Poor or non-visualization of intrahepatic vessels and diaphragm  THE HONG KONG POLYTECHNIC UNIVERSITY Cirrhosis cell death-> regeneration of liver cell-> alcohol cirrhosis Cirrhosis is not really a disease in itself but is a process associated with end-stage chronic liver disease. Result from a wide range of pathological processes including chronic hepatitis and alcoholic diseases. B and C  THE HONG KONG POLYTECHNIC UNIVERSITY Sonographic features of cirrhosis usually-> right lobe>left>caudate interchanged size – Volume / lobar redistribution rightlobe smeller parenchyma-> echolucent area Llc lobe – Coarse echotexture Mkro and meero nodules wavy appearance – Nodular surface not smooth portal con uence i obstructed abnormal development and growth – Nodules: regenerative and dysplastic obstructed portal vein uid collection at peritoneum – Portal hypertension (splenomegaly, ascites, and varices) small vein distending always scan spleen if the liver liver produce albumin (protein)-> seems to be cirrhotic go into bloodstream-> but portal vein-> drain from intestine to liver-> cirrhosis-> obstruct the return-> pressure in portal vein cirrhotic-> production obstructed->albumin go to bloodstream decrease-> homeostasis change-> osmotic pressure between the adjacent doppler US to access the change-> uid in the blood easily direction of blood ow of portal escaped to peritoneum-> ascites vein->normal go to to liver-> abnormal go away from liver  THE HONG KONG POLYTECHNIC UNIVERSITY regeneration ability of liver Regenerative nodules – Represent regenerating hepatocytes surrounded by a fibrotic septa. (tissue) – Similar architecture to the normal liver, and thus ultrasound is difficult to detect them. – Tend to be isoechoic or hypoechoic with thin echogenic borders which correspond to fibrofatty connective tissue. surrounding the regenerative cell  THE HONG KONG POLYTECHNIC UNIVERSITY Dysplastic nodules – Usually larger than regenerative nodules (≥ 10mm). – May be considered premalignant. – Varied echogenicity (hypoechoic, isoechoic or hyperechoic) – The level of echogenicity of dysplastic nodules correlates with their fat content, but does not predict the grade of the nodules (high or low). regular monitoring Kim et al. JUM 22:327-34, 2003  THE HONG KONG POLYTECHNIC UNIVERSITY hypoechoic-> ascites Lobar redistribution. Transverse scan shows the right lobe is smaller and there is an enlargement of the left right lobe -> reduce size lobe. transverse scan THE HONG KONG POLYTECHNIC UNIVERSITY usually homogenously hyperechoice Liver parenchymal alteration. Liver parenchyma is diffusely nodular (note the tiny hypoechoic right lobe masses within the liver), coarse echotexture. not homogenous heteregenous THE HONG KONG POLYTECHNIC UNIVERSITY Surface nodularity. Nodular liver surface. ascites-> hypoechoic nodular Best seen with ascites. the surface of liver is more separated from skin reduced size of liver  high risk of HCC-> chronic THE HONG KONG hepatitis, cirrhosis POLYTECHNIC UNIVERSITY subtle, di cult to see if high risk HCC patient-> if see these abnormalities-> do Contrast MRI or CT-> better than U/S U/S is best for initial, screening... Hypoechoic Hyperechoic Isoechoic Kim et al. JUM 22:327-34, 2003  THE HONG KONG POLYTECHNIC UNIVERSITY Ultrasound guided biopsy or intervention US guided biopsy – obtain tissue samples for cytology US guided intervention – treatment of disease, such as prescribe antibiotics too tumour, drainage of fluid, etc liver abscess guiding needle for RFA The role of US is to ensure the needle is in the appropriate location, such as within the mass, so that accurate tissue sampling and treatment can be performed. real time ability! THE HONG KONG POLYTECHNIC UNIVERSITY Examples of rfa treatment needles. THE HONG KONG POLYTECHNIC UNIVERSITY Examples of biopsy needle. trocar needle shell Needle closed (top) exposed Needle opened (bottom) when the needle is inside-> open it -> the liver tissue go inside-> put back the needle shell-> cut some tissues-> collect column of biopsy needle liver tissues-> better than cytology (FNA) THE HONG KONG POLYTECHNIC UNIVERSITY Biopsy guide is insertion direction is xed assembled onto the transducer. Biopsy needle is inserted into the biopsy guide. THE HONG KONG POLYTECHNIC UNIVERSITY With or without biopsy guide, the insertion of the needle is guided by real-time ultrasound. THE HONG KONG POLYTECHNIC UNIVERSITY Arrows indicate the tip of the needle. hyperechoic lesion THE HONG KONG POLYTECHNIC UNIVERSITY manipulate the transducer to put needle into the pathway The electronic pathway is activated on the image to guide the insertion of the needle. two dotted line-> electronic pathway for insertion THE HONG KONG POLYTECHNIC UNIVERSITY Gall Bladder  THE HONG KONG POLYTECHNIC UNIVERSITY Patient preparation and scanning technique enough bile accumulate-> distended gall bladder It is necessary to have 6 hours of patient fasting. turn right side up, for the gall bladder to drop away from rib Patient’s positioning: supine and right anterior oblique Scan planes: subcostal and lower intercostal scans Patient in full arrested inspiration usually allows better visualization of the gall bladder. push the gall bladder away downward away from ribs THE HONG KONG POLYTECHNIC UNIVERSITY Gall bladder is distended and can be clearly liver demonstrated when it is filled hypoechoic sac like structure with bile. Thus, should not have any hyperechoic fasting is necessary for accumulation of bile. THE HONG KONG POLYTECHNIC UNIVERSITY fundus body situated behind the gall bladder ipping backward Phrygian cap neck cystic duct and bile duct cross section of next page normal variation THE HONG KONG POLYTECHNIC UNIVERSITY look like a septum... Phrygian cap so two 90 degree plane scan is important THE HONG KONG POLYTECHNIC UNIVERSITY Junctional fold folding of gall bladder at neck y usually go into this way cystic duct and bile duct cross section-> septal like  THE HONG KONG POLYTECHNIC UNIVERSITY Gall stone (cholelithiasis) echogenic object very bright acoustic shadowing gall stone is mobile usually vs gall bladder polyp usually not mobile almost all U/s re ect back when ask patient to turn to di erent plane-> moving or not while hitting stone keeping transducer in same surface  THE HONG KONG POLYTECHNIC UNIVERSITY Gall stone (cholelithiasis) fundus o adhered Can you find the gall stones? THE HONG KONG POLYTECHNIC UNIVERSITY Multiple gall bladder polyps common young age may have too benign-> okay dik-> monitor echogenic measure size for stones and polyps not mobile-> arise from inner wall of gall bladder no acoustic shadowing behind  THE HONG KONG POLYTECHNIC UNIVERSITY in ammation of gall bladder Acute cholescystitis Sonographic signs – Gall stones gall bladder can see or not-> nd the location apply pressure-> pain or not positive: pain/ negative – Focal gallbladder tenderness (sonographic Murphy’s sign) adhere to the wall in ammated change of wall-> adhere – Impacted gall stone (does not move with patient’s position change) – Gallbladder dilatation some kind of uid level...-> uid mixture-> 堆壞死的東 -> echogenic – Sludge debris -> over the dependent side of patient – Diffuse wall thickening (> 2mm) pericholecystic uid THE HONG KONG POLYTECHNIC UNIVERSITY An oedematous, thickened gallbladder wall (arrows) with a stone. The hypoechoic areas show the oedema. THE HONG KONG POLYTECHNIC UNIVERSITY A gall bladder with oedematous, thickened wall (arrows) with stones. The hypoechoic areas show the oedema. THE HONG KONG POLYTECHNIC UNIVERSITY Transverse scan demonstrates pericholecystic fluid which is also hypoechoic common in acute cholecystitis proper patient preparation-> if not-> contraction-> smaller, thickened wall THE HONG KONG POLYTECHNIC UNIVERSITY Bile ducts  THE HONG KONG POLYTECHNIC UNIVERSITY Obstructive jaundice and bile duct dilatation Dilatation of all or part of the biliary tree is usually the obstruction of common bile duct-> next to result of proximal obstruction. The most common duodenum causes of obstruction are stones in the common bile duct or a neoplasm of the bile duct or head of pancreas. head of pancreas->high percentage of tumor than other part-> obstruct the bile duct upstream tail obstruction of CBD duodenum papilla ampulla of vater THE HONG KONG POLYTECHNIC UNIVERSITY common duct: CD because di cult to distinguish by the juction o common obstruction!!! pancreas tumor and stone THE HONG KONG POLYTECHNIC UNIVERSITY Common bile duct and main portal vein in the porta GB hepatis. liver longitudinal scan of CBD usually anterior to MPV and measure the diameter not larger than 0.8cm IVC  THE HONG KONG POLYTECHNIC UNIVERSITY outside the liver Size of extrahepatic bile duct can be used to identify bile duct dilatation. Common hepatic duct diameter ≥ 8mm is suggested biliary obstruction. Patients with previous biliary surgery or following liver transplantation may have larger common hepatic or common bile duct (≥ 10mm). medical history!!!! THE HONG KONG POLYTECHNIC UNIVERSITY Dilated common bile duct and a bile duct stone. l MPV acoustic shadowing THE HONG KONG usually scan liver rst-> if the intrahepatic BD dilated-> scan POLYTECHNIC UNIVERSITY GB as well-> to nd cause-> usually extrahepatic will also be dilated bile accumulation go upstream Itrahepatic bile duct dilatation. Echolucent tubular structures anterior to the portal veins irregular wall Irregularity of the walls of dilated bile ducts Whenever dilated intrahepatic bile ducts are detected, always check for extrahepatic bile duct dilatation and cause of obstruction. THE HONG KONG POLYTECHNIC UNIVERSITY irregular appearance Intrahepatic bile duct dilatation THE HONG KONG POLYTECHNIC UNIVERSITY END