Bài giảng Chuẩn đoán hình ảnh gan - Allen J. Cohen

Allen J. Cohen, Ph.D., M.D. Department of Radiological Sciences University of California, Irvine

Liver, Biliary Tree,Gallbladder

U gan lành tính

1. U tuyến (Hepatic adenoma) 2. Tăng sản thể nốt (Focal nodular hyperplasia) 3. Regenerating nodule 4. Nang (Cysts) 5. U tuyến đường mật (Biliary cystadenoma) 6. U máu (Hemangioma) 7. U mỡ (Lipoma) 8. Tụ máu (Hematoma) 9. Áp xe (Abscess) 10. Nhiễm mỡ vùng (Focal Fat)

U gan ác tính

1. Ung thư tế bào gan (Hepatocellular carcinoma) 2. Ung thư tế bào xơ dẹt (Fibrolamellar HCG) 3. Ung thư nguyên bào gan (Hepatoblastoma) 4. Ung thư đường mật (Cholangiocarcinoma) 5. Nang ung thư (Cystadenocarcinoma) 6. U máu ác tính (Angiosarcoma) 7. U biểu mô mạch máu (Hemangioendothelioma) 8. U hạch nguyên phát (Primary lymphoma) 9. Di căn (Metastasis)

Các phương pháp chẩn đoán hình ảnh:

Chụp cắt lớp vi tính Computed Tomography: 1. Đánh giá giai đoạn và theo dõi di căn. 2. Chẩn đoán các u nguyên phát: hepatoma, adenoma,

FNH, cholangioCa.

3. Áp xe. 4. Chấn thương bụng kín. 5. U hạ sườn phải. 6. Bệnh gan lan tỏa:Budd-Chiari, hemochromatosis. Siêu âm: 1. Nang và tổn thương đặc. 2. Siêu âm Doppler: tưới máu, TMC. 3. Đường mật và túi mật +++. 4. U hạ sườn phải. 5. Tìm tổn thương trong phẫu thuật.

Các phương pháp chẩn đoán hình ảnh:

Y học hạt nhân 1. U máu. 2. U gan. 3. Lưu thông mật. 4. Chức năng gan.

Chụp cộng hưởng từ hạt nhân (MAGNETIC

RESONANCE IMAGING)

1. U máu 2. Nang. 3. Nhiễm mỡ vùng. 4. U gan: nguyên phát hay thứ phát.

I. Nang gan

Bẩm sinh, sau nhiễm trùng, sau chấn thương, nhiễm ký sinh trùng.

Bẩm sinh-hay gặp.

CT: Không ngấm thuốc, thành mỏng và đều.

Nhiều nang gan 40% .

Nang nhỏ < 1 cm khó phát hiện bằng CT hay US.

Chẩn đoán phân biệt: di căn gan, áp xe nhỏ (metastasis, micro-abscess).

Nang gan đơn thuần

 Bẩm sinh

Nhiều nang gan

 Trên CT nghĩ đến di căn

Nhiều nang gan

 Gan thận đa nang

Áp xe gan

Nguồn: Máu, đường mật, sau chấn thương, sau phẫu thuật CT: Giảm tỷ trọng, ngấm thuốc vỏ US: Giảm âm, khí bên trong A míp: Lớn, bên phải Sán chó (Echinococcal): vách, vôi hóa vỏ trứng++ Nấm: Nhiều, nhỏ Nhiễm trùng mủ: đặc, lớn

 A míp

Áp xe a míp

 Khí bên trong

 Thuốc cản quang vòa ổ áp xe do thông với tá tràng

Sán chó

Echinococcal abscess

 Membranes within cyst  E. granulosis

Echinococcal abscess

 MRI-Large liver abscess-daughter cysts

Áp xe do nấm

 Ổ áp xe nhỏ được phát hiện vớ cửa sổ hẹp

Áp xe gan

 Áp xe lách do nấm

 Áp xe do vi khuẩn

Viêm gan do ban xuất huyết

Sau bị mèo cào

U tuyến tế bào gan

1. Dạng nang, vỏ xơ

2. Phụ nữ trẻ, thuốc

3. Đau do u, chảy máu

4. Tiền ung thư

5. Chẩn đoán: CT

 Máu tụ dưới bao gan do vỡ adenoma

U tuyến tế bào gan

 Ngấm thì ĐM

Tăng sản thể nốt (Focal nodular hyperplasia)

phase

in portal venous phase

 Enhances in arterial  Becomes isodense

Focal Nodular Hyperplasia

 Pedunculated FNH with central scar- remnant of AVM

Focal nodular hyperplasia

 Tc sulfur colloid avid

 Central scar

Focal nodular hyperplasia

 Central scar

 Focal nodular hyperplasia

Regenerating Nodules

 Cirrhotic liver-spontaneous spleno-renal shunt

Hemangioma

1. 2. 3. 4.

Occurrence – 10% of adults; F>M. Thin-walled vascular spaces without smooth muscle. Slow circulation. Hemorrhage – rare.

Diagnosis: 1. 2.

Ultrasound: round echogenic focus without hypoechoic halo. CT: precontrast – hypodense mass. contrast – rim enhancement initially. delay – centripetal filling in. 3. Tc-labeled RBCs for lesions > 2 cm. 4. T2-weighted MR for lesions < 2cm.

hemangioma

 Classic echogenic

ultrasound finding of hemangioma

mimicking a liver abscess

 Hemangioma

hemangioma

 Lesion fills in

enhancement

from periphery

 Globular peripheral

hemangioma

 Globular peripheral

not be echogenic

enhancement

 Large hemangiomas may

hemangioma

 Contrast filling in from periphery

hemangioma

 Lesion fills in on Tc tagged RBC scan

 Photopenic on Tc sulfur colloid scan

hemangioma

 Hemangioma caused feeling of early satiety

Thrombosed hemangioma

 CT of thrombosed hemangioma

 Thrombosed hemangioma thought to be hepatoma

Thrombosed hemangioma

hemangioma

before-5 years earlier

 Large thrombosed  Same patient as

Giant Hemangioma

 Interrupted globular enhancement of periphery is characterisic

Multiple Hemangiomas

characterisic

 Interrupted globular enhancement of periphery is

Hepatocellular carcinoma

1. Vascular malignant tumor – solitary or multifocal.

2. Tumor thrombus, hemorrhage, metastases.

3. Elevated alpha-fetoprotein ( 80% of patients.)

4. Associated with hepatitis B, hepatitis C, alcohol

Diagnosis:

1. CT: inhomogeneous enhancement, delayed isoattenuation

fibrous capsule – may mimic adenoma.

2. NM: Gallium uptake 90%.

Hepatoma

 Enhancing lesion in arterial phase in lateral segment of

left lobe.

Hepatoma

and sulfur colloid cold

 SPECT/CT scan shows tumor to be Gallium avid

hepatoma

enhancement

precontrast phase

 Very subtle arterial  Faintly seen on

hepatoma

 Different patient- multiple small hepatomas

 Best seen on portal venous phase (not common)

hepatoma

 Same patient – other small hepatomas

Tiny Hepatoma

 Examination obtained with cardiac gating

Multiple hepatomas

 Multiple hepatomas  Embolization coils in

gastroduodenal artery prior to therasphere embolization

hepatoma

 Large hepatoma  Portal vein thrombosis

hepatoma

 Large hepatoma  Lung metastasis

hepatoma

 Cavernous

 Large hepatoma with portal vein thrombosis

transformation of portal vein

hepatoma

 Gallium 67 citrate

avid tumor

 Hepatoma adjacent to thrombosed portal vein

hepatoma

hepatoma

 Recurrent treated  Portal vein thrombosis

hepatoma

vein thrombosis

pneumatosis intestinalis

 Superior mesenteric  Infarcted colon-

hepatoma

treatment with Radiofrequency Ablation

 6 months later after  Hepatoma

hepatoma

 Yttrium microsphere embolization of right lobe hepatoma: large tumor has become necrotic,

 new hepatomas have appeared in left lobe

Hepatoma chemoembolization 50 mg cisplatin, 50 mg doxyrubicin, Embogold microparticles 300-500 microns

Suspected hepatoma

 Hep C positive and

 Lesion missed on CT and

rising alpha feto protein

MRI

Suspected hepatoma

CT 6 months later

 Hepatoma detected by

 Liver-Spleen scan suggested lesion

hepatoma

 Pedunculated hepatoma

Fibrolamellar Hepatoma

 Young non cirrhotic patient, normal AFP

Hepatic lymphoma

 Multiple liver lesions

 Obstructing left kidney  Destroying verterbral body

Liver malignancies

 Lymphoma  Cholangiocarcinoma

Cholangiocarcinoma

 Tumor occupies lateral segment of left lobe  Metastases in right lobe

Hepatic metastases

1. Colon, breast, lung, pancreas –

hepatic artery supply.

2. CT: hyperattenuating,

hypoattenuating or hypoattenuating with rim enhancement.

Hepatic metastases

metastatic colon Ca

liver

 metastasis in fatty

Hepatic Metastases

Initial presentation ,three months,15 months,18 months

Hepatic Metastases

 Colon carcinoma metastatic to lliver and lungs

Hepatic Metastases

metastasis and absent left breast

 Metastatic breast cancer-note sclerotic veterbral

Liver segments

Segment characterization

 Segmental anatomy better

depicted on MRI –orthogonal planes than single slice CT. multislice CT may be best

 Liver metastasis

Liver lesion diagnosis

metastases

 CT arterial portography

 CT arterial portography- thrombosed right portal vein

Carcinoid metastases

metastases-unusual

enhancement of carcinoid metastasis

 Classic arterial  Cystic carcinoid

Carcinoid metastases

Arterial phase images, narrow and wide windows

Portal venous phase imaging

Carcinoid metastases-after treatment with octreotide

Less vascularity in Arterial phase

Partially necrotic in portal venous phase

Fatty liver

DIFFUSE HEPATIC DISEASE

1. Fatty infiltration – focal diffuse.

Chemotherapy, hyperalimentation, alcohol, obesity, diabetes, hyper- triglycerides. CT: normal liver 5-10 Hounsfield units > spleen on noncontrast scan

2. Cirrhosis – alcoholism, viral

hepatitis, cryptogenic cirrhosis, sclerosing cholangitis.

 Diffusely fatty liver

Focal fatty liver

1. Sequella of chemotherapy,

random.

2. CT: normal vascular pattern.

3. MR: fat-suppression.

Focal fatty liver

 Normal vascularity

 Focal Fat- T1 Fat Sat

preserved

Focal Fatty Liver

 Suspected mass on ultrasound  Focal Fatty Liver on CT

Focal fatty liver

 Focal normal liver in sea of fatty liver-two cases

cirrhosis

 Regenerating nodules  Ascites  Recanalized periumbilical

vein

 Caput Medusa

cirrhosis

 Recanalized periumbillical

vein

 Partial thrombosis of

portal vein

 Coronal reformation

cirrhosis

 Giant paraesophageal varices and coronary vein,

cavernous transformation of portal vein,

 Patient with cirrhosis and hepatoma

Cirrhosis-hepatofugal flow

Diffuse hepatic disease

Hemochromatosis – congenital, iron overload.

Transfusional hemosiderosis – anemia treatment.

CT non-contrast – normal 50-60 HU.

Abnormal 70-100 HU.

hemochromatosis

 Dense liver-

Diffuse hepatic disease

leukemia

 Post transfusional hemosiderosis in child with

Budd-Chiari malformation

DIFFUSE HEPATIC DISEASE

Budd-Chiari syndrome:

Chronic hepatic vein congestion. Tumor, web, phlebitis, blood dyscrasia – thrombus.

CT: Hepatomegaly – central, caudate lobe enhancement. Hypodense periphery. Central veins not seen.

 Suspected gastric leiomyosarcoma

Budd-Chiari Syndrome

be a hepatoma

 Massively enlarged caudate lobe-thought to

Budd-Chiari Syndrome

 Portal venous flow  No hepatic venous flow

Budd-Chiari Syndrome

veins

another patient with Budd- Chiari syndrome

 Occluded hepatic  Post biopsy biloma in

Portal Vein Thrombosis

Portal vein thrombosis with cavernous transformation

Post transplant evaluation

 Hepatic artery patency

Intraoperative ultrasound

1. Focal masses 2. Transplant vascularity

Intraoperative ultrasound

 Needle localization  Probe localization

BILIARY TREE

CONGENITAL ABNORMALITIES

1. Choledochal cyst – marked extra-hepatic

dilation, minimal to no intrahepatic dilation. Risk: stones, cholangiocarcinoma.

2. Choledochocele – focal dilation of distal

CBD.

3. Caroli’s disease – segmental dilatation of

intrahepatic bile ducts associated with renal cysts, MSK.

Congenital abnormalities

 Choledochal cyst  Choledochocele

Congenital abnormalities

 Caroli’s disease  Choledocal diverticula

Choledochal cyst

 CT-Choledochal cyst

Choledochal cyst

 Ultrasound  MRI

Choledochal cyst

 Hepatobiliary scan  CT

Choledochal cyst

cholangiocarcinoma

 6 months later - metastatic  US- thick wall cyst

Biliary tree

Benign stricture – gradual tapering

Malignant stricture – abrupt cutoff

duct

 Hamartoma of bile

Inflammatory

1. Acute cholangitis – biliary gas, wall enhancement

2. Sclerosing cholangitis – association – UC, Crohn

disease, retroperitoneal fibrosis. Extra (95%) & intrahepatic strictures. Beaded ducts. Focal dilatation – suspect cholangiocarcinoma.

3. Recurrent pyogenic cholangiohepatitis

Marked extrahepatic, intrahepatic duct dilatation. Numerous stones – cast of biliary tree

4. Choledocholithiasis.

Pericholecystic abscesses

 Pericholangitic

abscesses

 Different patient -AIDS- abscesses-liver,spleen

AIDS cholangitis

 AIDS gallbladder  Beaded ducts

AIDS cholangitis

 CMV cholecystitis  AIDS gallbladder

AIDS cholangitis

 Papillary stenosis-AIDS cholangitis

Cholangitis

primary bilary cirrhosis

 Periportal nodes-  Sclerosing cholangitis

recurrent pyogenic cholangiohepatitis

intrahepatic stone

monk with right upper quadrant pain

 Vietnamese Buddhist  Calcified soft

Recurrent cholangiohepatitis

 Soft common duct stone  Stone in left duct

Common bile duct stone

bile duct stone-filling of intrahepatic radicles, no tapering at ampulla

 Subtle distal common  After stone removed

Common bile duct

 Ischemic stricture

 CBD entering diverticulum

Common bile duct obstruction

 Tension from T-Tube

 Different patient- jaundiced-dilated intrahepatic bile ducts

Common bile duct

duct on Tc hepatobiliary scan

 Common duct stone  No excretion into bile

Common bile duct obstruction

bile ducts

 Dilated intrahepatic  stone in distal CBD

cholangiograms

leak

 Ducts of Luschka-bile  pancreatitis

Bilary tree: neoplastic disease

1. Cholangiocarcinoma – Klatskin, intrahepatic, extrahepatic.

2. Metastatic to porta hepatis – lymphoma, ovarian, colon,

gallbladder, pancreas, stomach.

CHOLANGIOCARCINOMA

1. Klatskin tumor

a. CT detection of mass difficult. b. ERCP.

2. Peripheral – may be multifocal.

Sclerosing cholangitis

later-cholangiocarcinoma

 ERCP  Same patient-7 years

cholangiocarcinoma

 Klatzkin tumor at confluence of ducts

cholangiocarcinoma

 ERCP showing stented obstructing stricture

cholangiocarcinoma

atrophy

 Dilated ducts with  ERCP showing stricture

cholangiocarcinoma

hepatis

 Obstruction at porta  Stented tumor

cholangiocarcinoma

ducts

tumor

 Dilated intrahepatic bile  Delayed enhancement of

Cholangiocarcinoma

 Intraductal tumor-

thought to be stones or clot

 6 months later, tumor enlarged, obstructing ducts

cholangiograms

 Pancreatic tumor

obstructing common bile duct

 cholangiocarcinoma obstructing common bile duct

Ovarian Carcinoma metastatic to porta hepatis

Biliary dilatation, masses at porta, retroperitoneal adenopathy, left ovarian cystadenocarcinoma

MRCP

 MRCP-stone at

 MRCP-common duct

ampulla

stones

MRCP

previous CT scan

 Low insertion of cystic duct not appreciated on

Gallbladder

 cholesterol polyps

Oral cholecystograms

 Polyps  hypercontractility

gallbladder

 Septated gallbladder

gallbladder

 CT - adenomyosis  US - adenomyosis

gallstone

ultrasound

 No stone seen on  Gallstone seen on CT

Gallstones

 Fissured Cholesterol Stones

cholecystitis

 right portal vein

 Cholecystitis as cause of

right portal vein thrombosis

thrombosis-THAD-transient hepatic attenuation difference-right lobe enhances before left lobe

Acute cholecystitis

 Calcified gallstones

 Perforated gallbladder with pericholecystic inflammation

Acute emphysematous cholecystitis

surgery

 Usually diabetic patients, need emergency

Gallbladder Cancer





6.500 Deaths/year in U.S. 3:1 Female:male

Radiology:     

Mass replacing gallbladder 40-65% Focal/diffuse wall thickening 20-30% Intraluminal mass 15-25% Gallstones in 70-80% Porcelain gallbladder – 25% risk of cancer

SPREAD OF GALLBLADDER CANCER Extension into liver. 1. Extension into subhepatic space. 2. Extension into bowel. 3. Extension to extrahepatic bile duct. 4. 5. Lymphatic. 6. Hematogenous

Gallbladder Cancer

liver

 Tumor growing into  Stones on ultrasound

Jaundiced patient

gallbladder

ducts

 Nonvisualization of  Dilated intrahepatic

Jaundiced patient

 Subtle gallbladder cancer

 Obstruction at porta hepatis on ERCP

Gallbladder carcinoma

 Perforated gallbladder

cancer with pericholecystic abscess

 Gallbladder cancer growing into liver

Gallbladder carcinoma

 right portal vein thrombosis-THAD-

Gallbladder cancer as cause of right portal vein thrombosis

transient hepatic attenuation difference-right lobe enhances before left lobe

Leiomyosarcoma of gallbladder

Ultrasound-anechoic

CT- homogeneous mass

mass

Leiomyosarcoma of gallbladder

suspected metastasis

anterior to fatty liver

 Post therapy-  Focal normal liver

Patient with vomiting

 MR-gallstone in empyema of

in right upper quadrant

gallbladder obstructing stomach, patient also has cystic lesions of kidneys-tuberous sclerosis

 Large gas collection

Quiz Case-elderly patient with severe abdominal pain

Quiz Case

 CT scan two years earlier

Perforated Gallbladder

 Gallstones are now in peritoneal cavity