Ultrasound diagnostic of pathological changes and complications in patients with a transplanted liver

Nakon transplantacije jetre može doći do različitih komplikacija koje dijelimo na ranog i kasnog postanka. One uključuju vaskularne i bilijarne komplikacije, tekuće kolekcije te neoplastičke promjene (hepatocelularni karcinom, metastaze). Ultrazvuk je najraširenija, najdostupnija i najjeftinija pretraga za prikaz jetrene patologije. Pomoću nje vrlo brzo i efektivno možemo postaviti dijagnozu već uz pacijentov krevet, bez potrebe premještaja pacijenta. Prednost koju ultrazvuk i magnetska rezonanca (MR) imaju nad kompjutoriziranom tomografijom (CT) je nedostatak ionizirajućeg zračenja, što je od velike važnosti s obzirom da je zdravlje pacijenta uvijek na prvom mjestu. Najčešće vrste ultrazvuka koje koristimo prilikom dijagnostike jetrenih patologija su color, power i pulse wave Doppler. Pomoću njih dobivamo podatke o toku krvi u žilama kako slikovno tako i računski putem indeksa otpora, što je važno kod sumnje na opstrukciju ili stenozu krvnih žila jetre. Također, otvorenost portalne vene prije transplantacije i evaluacija tromboze jetrene arterije poslije transplantacije obavlja se ultrazvukom. Korištenjem ultrazvučnih kontrasta, poput onih punjenih zrakom ili nisko topivim plinovima, bolje opisujemo izgled žila jetre i lakše raspoznajemo benigne od malignih tumora. Za bolji prikaz vaskularnih struktura možemo koristiti i CT. MR se, u obliku magnetske kolangiopankreatografije, češće koristi kod bilijarnih komplikacija i za prikaz bilijarnog stabla. U ovom diplomskom radu opisuju se metode detekcije i načini dijagnostike posttransplantacijskih komplikacija i patoloških promjena jetre kod pacijenata s transplantiranom jetrom.Following liver transplantation, various complications can occur, which we then divide into those of early and late onset. These include vascular and biliary complications, fluid collections and neoplastic changes (hepatocellular carcinoma, metastases). Ultrasound is the most widespread, most accessible and the cheapest examination used for imaging liver pathology. With it, very quick and efficient diagnostics can be done right next to the patient's bed, without moving the patient elsewhere. The advantage that ultrasound and magnetic resonance (MR) have over computed tomography (CT) is the lack of ionizing radiation, which is of great importance given that the health of the patient always comes first. The most common types of ultrasounds we use while diagnosing liver pathology are color, power and pulse wave Doppler. They are used to obtain data of the blood flow in the vessels, both visually and computationally while using the resistance index, which is important when we are suspecting obstruction or stenosis of the liver blood vessels. Also, the patency of the portal vein before transplantation and the evaluation of the hepatic artery thrombosis after transplantation are performed by ultrasound. By using ultrasound contrasts, such as those filled with air or low-soluble gases, we can better describe the appearance of the liver vessels and more easily distinguish benign from malignant tumours. For better imaging of vascular structures, we can also use CT. MR, in the form of magnetic cholangiopancreatography, is more commonly used in diagnosing biliary complications and to display the biliary tree. This thesis describes the methods of detection and diagnosis of posttransplant complications and pathological changes of the liver in patients that underwent liver transplantation