Neinvazivno ispitivanje moždanog krvotoka tijekom kortikalne aktivacije

doctoral thesis

• Author: Marijana Lisak; MBZ: 299383
• Mentor: Vida Demarin (mentor)
• Committee member: nije dostupno (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2007-10-31, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences
• Universal decimal classification (UDC): 61 - Medical sciences

Abstract

U ovom istraživanju smo usporedili dvije različite metode za funkcionalni prikaz mozga tijekom moždane aktivacije, fTCD i SPECT, u svrhu prepoznavanja vrijednosti i primjene fTCD-a kao potpuno neinvazivne, jednostavne, pouzdane i pristupačne tehnike koja se može koristiti kao komplemetarna metoda SPECT-u u funkcionalnom prikazu mozga. Usporedbom obje metode naglašava se prednost fTCD-a s obzirom na neškodljivost i praktičnost metode. Metoda fTCD-a se pokazala vremenski nezahtjevnom i osjetljivom metodom za mjerenje moždane aktivacije, uz znatno bolju vremensku rezoluciju ali nedostatak odgovarajuće prostorne rezolucije koju posjeduje SPECT. U istraživanje je bilo uključeno 60 zdravih ispitanka-dešnjaka kod kojih je učinjeno bilateralno fTCD snimanje obje ACM tijekom razdoblja mirovanja i tijekom izvođenja složenog aktivacijskog modela s elementima vidno-prostorne dikriminacije, te izmjeren relativni porast BSK. U podgrupi od 15 ispitanika učinjen je SPECT pod istim uvjetima i izmjeren relativni porast moždane perfuzije. Statistički značajna povezanost između dviju metoda mjerenja (r=0,5608; P=0,030; koeficijent determinacije r2=0,3154) utvrđena je za po jedan od parametara: brzina strujanja krvi u desnoj ACM u aktivaciji mjerena fTCD-om i relativna promjena perfuzije desne strane mjerena 99mTc-HMPAO SPECT-om što ukazuje da te dvije metode samo djelomično mjere iste karakteristike vezane uz aktivaciju određenog dijela mozga. Utvrđena je značajna upravo proporcionalna povezanost rezultata izmjerenih u aktivaciji s rezultatom u mirovanju za odgovarajuću stranu i metodu mjerenja (P<0,001 za sve) uz značajnu (ali obrnuto proporcionalnu) povezanost s relativnom promjenom (aktivacija u odnosu na mirovanje) (P<0,001 za sve osim desnu stranu mjerenu SPECT-om) što pokazuje da postoji određeni gornji plato tijekom aktivacije te da je isti dosegnut tijekom aktivacije odnosno znači da je aktivacijski model dobro odabran. Obje metode mjerenja (fTCD i SPECT) pokazale su se dovoljno osjetljivima u mjerenju moždane aktivacije, odnosno korištenjem obje metode mjerenja utvrđen je statistički značajan porast moždanog protoka obostrano u aktivnosti u odnosu na mirovanje (P<0,0001).

Abstract (english)

The purpose of the study was cross-validation of Functional Transcranial Dopler (fTCD) with Single Photon Emission Computed Tomography (SPECT) during complex activation paradigm in order to demonstrate that fTCD is non-invasive, reliable, easy-to-use, inexpensive method, which can be used as complementary tool in comparison with SPECT and other functional neuroimaging methods. Further on, fTCD is a practical and safe method in evaluation with SPECT which includes radiation exposure and is time-consuming. This study suggests that fTCD is sensitive method with high temporal resolution and can be used for detecting brain activation. Bilateral continuous middle cerebral artery (MCA) monitoring of 60 healthy, right-handed subjects with fTCD was performed while the subjects underwent an activation task with visuospatial elements, and the hemispheric blood flow velocity increase was calculated. Identical stimulus and response patterns were used in the subgroup of 15 subjects, which underwent SPECT, and the hemispheric perfusion increase was calculated. Statistical analysis showed significant correlation between fTCD and SPECT (r=0,5608; P=0,030; r2=0,3154) for: blood flow velocity (BFV) in the right MCA during activation-measured with fTCD and relative right-sided perfusion increase-measured with 99mTc-HMPAO SPECT. Results suggest that both methods only partially measure same features related to brain activation in specific cortical areas. Statistically significant and proportional correlation between activation and baseline measurement results was found for both methods according to the side (P<0,001, respectively). Significant non-proportional correlation of relative increase was found for all (except for SPECT right-side relative increase) which suggests that certain level of stability (plateau) during activation was achieved and that activation paradigm was correctly selected. Both methods (fTCD and SPECT) succeeded in discriminating brain activation. Statistically significant increase of cerebral blood flow was detected by fTCD and SPECT (P<0,0001), suggesting that both methods are sensitive for investigation of close relationship between brain activity and cerebral blood flow.

• Keywords: medicina
• Keywords (english): medicine
• Language: croatian
• URN:NBN: urn:nbn:hr:105:694258
• Study programme: Title: Biomedicine and Health Sciences; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstva (doktor/doktorica znanosti, područje biomedicine i zdravstva)
• Type of resource: Text
• Extent: 110 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-05-05 08:40:20