Razmejitev in volumetrija talamusa v magnetnoresonančnih slikah

ROZMAN, AGNES (avtor), Špiclin, Žiga (mentor)

Talamus je struktura v možganih, ki nadzira stanja budnosti, spanja in zavesti. Nevrodegenerativne bolezni, kot je multipla skleroza (MS), prizadenejo živčne celice, torej tudi talamus. Z razmejitvijo talamusa v magnetnoresonančnih (MR) slikah bi lahko izmerili njegov volumen in tako ugotovili povezavo med volumnom talamusa in stopnjo napredovanja multiple skleroze. V nalogi smo razvili avtomatski postopek za razmejitev talamusa na podlagi poravnave atlasov, tj. slik z danimi razmejitvami talamusa, na ciljno MR sliko in zlivanjem poravnanih atlasov. Zbirko atlasov smo pripravili na podlagi ročnih razmejitev. Avtomatska razmejitev talamusa z uporabo poravnave na osnovi afine preslikave in preslikave z B-zlepki ter zlivanja s postopkom glasovanja z večino je bila glede na kvantitativno vrednotenje najbolj kakovostna. Za analizo smo uporabili T1-utežene MR slike 87-ih oseb z boleznijo MS in 88-ih zdravih oseb. Nazadnje smo poiskali povezave med izračunanimi (normiranimi) volumni talamusa in kliničnimi ter demografskimi podatki bolnikov ter primerjali volumne med MS bolniki in zdravimi. Po pričakovanjih volumen talamusa pada s staranjem, daljšim trajanjem bolezni in višanjem splošne stopnje funkcionalne prizadetosti bolnikov, medtem ko narašča z daljšim trajanjem izobraževanja in višjimi rezultati kognitivnih testov delovanja spomina. Z merjenjem volumna talamusa bi tako lahko omogočili višjo kvaliteto življenja bolnikov z MS, predvsem zaradi možnosti zgodnejšega in bolj potentnega zdravljenja.

• Jezik: Slovenski jezik
• Ključne besede: talamus, avtomatska razmejitev MR slik, multipla skleroza
• Vrsta gradiva: Magistrsko delo/naloga
• Organizacija: FE - Fakulteta za elektrotehniko
• Leto izida: 2019
• PID: 20.500.12556/RUL-106203
• Datum objave v RUL: 11.02.2019

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Segmentation and volumetry of talamus in magnetic resonance images

Izvleček

Thalamus is a structure in the brain that controls states of awakeness, sleeping and consciousness. Neurodegenerative diseases like multiple sclerosis (MS) cause damage to nerve cells including cells in the thalamus. With segmentation of thalamus in magnetic resonance (MR) images we could calculate volume of thalamus and relate it to the disability caused by the disease. In this thesis we developed an automated segmentation method based on co-registration of atlases, which contain thalamus segmentations, onto the target MR image and fusion of the atlases. The dataset of atlases was created by manually segmenting the MR images. Automated segmentation of the thalamus with affine and B-spline based registration and majority voting atlas fusion yielded best quality according to quantitative evaluation. The evaluation was based on T1-weighted MR images of 87 subjects with MS and 88 healthy subjects. We also investigated the relationships between the (normalized) thalamic volumes and the clinical and demographic data and compared the volume between MS and healthy subjects. Similarly to previous reports in the literature the thalamic volumes decreased with increasing age, extended disease duration, and increasing functional disability of the MS patients. On the other hand, the thalamic volumes increased with years of education and results of the cognitive memory tests. By measuring the volume of thalamus we could thus enable higher quality of life of the MS patients as a result of the possibility of earlier and more potent treatment.

• Ključne besede: thalamus, authomatic segmentation of MR images, multiple sclerosis