diplomsko delo
Ana Maria Zaman (Avtor), Tina Starc (Recenzent), Janez Žibert (Mentor), Sašo Arnuga (Komentor)

Povzetek

Uvod: Ultrazvok je mehansko valovanje, ki se uporablja za pregledovanje notranjosti človeškega telesa. Je zvok s frekvenco nad 20 kHz. V zadnjem času je ultrazvok ena najpogosteje uporabljenih diagnostičnih metod. Opiše se s frekvenco, valovno dolžino in jakostjo. Poznamo način A, način B in način M pridobivanja slike. Prvi temelji na principu amplitudne modulacije, drugi predstavlja klasično metodo pridobivanja slike, tretji način pa uporabljamo zaradi dobrega prikaza aksialne in časovne ločljivosti. Slike pridobivamo s pomočjo ultrazvočne sonde. Poznamo linearno, konveksno in sektorsko sondo. Strukture, ki jih prikažemo na zaslonu, definiramo s pojmom ehogenost. Svetle strukture na sliki imenujemo hiperehogena področja, hipoehogena so manj svetla polja, anehogena pa so črna polja na sliki. Poleg anatomskih struktur se na ultrazvočnih slikah pogosto pojavijo artefakti, ki so posledica interakcij ultrazvočnega snopa s tkivom ali pa lastnosti snopa. Artefakti na ultrazvočni sliki lahko povzročijo napačno postavitev diagnoze, nekaterim se lahko izognemo. Ključnega pomena je poznavanje fizikalnega ozadja delovanja ultrazvoka in razumevanje širjenja ultrazvočnega snopa po tkivu. Namen: V diplomskem delu bomo prikazali, opisali in analizirali najpogostejše ultrazvočne artefakte, ki se pojavljajo v ultrazvočni diagnostiki. Predstavili bomo kdaj in zakaj se pojavijo, kako jih lahko na ultrazvočni sliki prikažemo sami in kako se jih lahko znebimo, kadar nam onemogočajo pravilno postavitev diagnoze. Metode dela: V diplomskem delu smo uporabili deskriptivno metodo s pregledom literature. Iskali smo literaturo s področja ultrazvoka, fizikalnega ozadja ultrazvoka in ultrazvočnih artefaktov. Znanstvene in strokovne članke smo iskali po slovenskih in angleških podatkovnih bazah, slovenskimi in angleškimi ključnimi besedami. Na koncu smo teorijo preverili tudi v praksi in s pomočjo fantomov prikazali nekatere artefakte. Rezultati: V rezultatih so predstavljeni članki, ki smo jih uporabili za pregled literature. Podrobno smo opisali najpogostejših petnajst ultrazvočnih artefaktov. Delili smo jih tudi glede na pojavnost pri B načinu slikanja in Dopplerjevem pojavu, kot tudi na lokacijo, kjer se pojavijo. Izvedli smo še eksperimentalni del, s katerim smo teorijo s pomočjo fantomov dokazali še v praksi. Razprava in zaključek: Artefakti pri ultrazvoku so lahko moteči ali pa nam pomagajo pri postavitvi diagnoze. Nekaterim se lahko izognemo, druge delno odstranimo s slike, pri tretjih pa je pomembno, da jih na sliki prepoznamo, ker artefakta ne moremo odstraniti. Z eksperimentalnim delom diplomskega dela smo ugotovitve iz pregleda literature potrdili v praksi. Menimo, da je bil naš cilj dosežen.

Ključne besede

diplomska dela;radiološka tehnologija;ultrazvok;ultrazvočne sonde;delovanje ultrazvoka;ultrazvočni artefakti;artefakti;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.11 - Diplomsko delo
Organizacija: UL ZF - Zdravstvena fakulteta
Založnik: [A. M. Zaman]
UDK: 616-07
COBISS: 121289219 Povezava se bo odprla v novem oknu
Št. ogledov: 9
Št. prenosov: 4
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: Artifacts in diagnostic medical ultrasound
Sekundarni povzetek: Introduction: Ultrasound is a mechanical wave, which is used to observe the inside of a human's body. It is a sound with frequency over 20 kHz. Recently, the ultrasound has become one of the most frequently used diagnostic methods. The ultrasound is described by frequency, wavelength and intensity. There are three different methods for obtaining an image using the ultrasound, A – mode, B – mode and M – mode. A – mode uses a single transducer, that scans a line through the body and marks echoes on a screen as a function of depth. B – mode represents a classic method of obtaining images and M – mode is used for its good display of axial and temporal resolution. Images are made with the help o fan ultrasound transducer, also called a probe. There are three types of ultrasound transducers, linear, convex and sector transducers. The structures shown on screen differ in colour. A hyperechoic signal in very bright and light in color, a hypoechoic signal appears darker and an anechoic signal appears black. Beside anatomical structures, the ultrasound images often show artifacts, resulting from the interactions of the ultrasound beam with the tissue or properties of the beam. Artifacts on an ultrasound image can be avoided by knowing how the ultrasound works, and understanding how the ultrasound beam spreads through tissues. Purpose: The aim of this diploma work is to show, describe and analyse the most common ultrasound artifacts that occur in ultrasound diagnostic. We will discuss when and why the artifacts occur, how we can show them on an ultrasound image ourselves and how we can get rid of them, when they prevent us from making a correct diagnosis. Methods: In this diploma work, we used a descriptive method with a review of literature. We collected the analysed material from the field of ultrasounds, mechanics of ultrasound and ultrasound artifacts. The reviewed materials were collected from Slovenian and English databases, with the help of Slovenian and English key words. At the end, we also tested the theory in practice and showed some artifacts with the help of phantoms. Results: The results present the articles we used to review the literature. It contains a detailed description of the fifteen most common ultrasound artifacts. We divided them according to occurrence in B – mode imaging and Doppler imaging, as well as the location were they are presented. We also preformed an experimental part, with which we proved the theory in practice with the help of phantoms. Discussion and conclusion: Ultrasound artifacts can be disruptive to our diagnosis or they can help us with it. Some artifacts we can avoid, some we can partly remove from the image and for others it is crucial that we recognise them because they cannot be removed or avoided. With the experimental part of this diploma work we confirmed the findings from the literature review in practice. We believe that our goal has been achieved.
Sekundarne ključne besede: diploma theses;radiologic technology;ultrasound;ultrasound transducers;ultrasound procesings;ultrasound artifacts;artifacts;
Vrsta dela (COBISS): Diplomsko delo/naloga
Študijski program: 0
Komentar na gradivo: Univ. v Ljubljani, Zdravstvena fak., Oddelek za radiološko tehnologijo
Strani: 63 str.
ID: 16458522