title: A new automatic phase mask filter for high-resolution brain venography at 3 T: theoretical background and experimental validation.
abstract: To improve vessel contrast in high-resolution susceptibility-based brain venography, an automatic phase contrast enhancing procedure is proposed, based on a new phase mask filter suitable for maximizing contrast of venous MR signals. The effectiveness of the new approach was assessed both on digital phantoms and on acquired MR human brain images, and then compared with venographic results of phase masking methods in recent literature. The digital phantom consisted of a simulated MR dataset with given signal-to-noise ratios (SNRs), while real human data were collected by scanning healthy volunteers with a 3.0-T MR system and a 3D gradient echo pulse sequence. The new phase mask (NM) was more effective than the conventional mask (CM) both on the digital phantoms and on the acquired MR images. A quantitative comparison based on phantom venograms indicates how this phase enhancement can lead to a significant increase in the contrast-to-noise ratio (CNR) for all considered phase values as well as for all vessel sizes of clinical interest. Likewise, the in vivo brain venograms reveal a better depiction of the smallest venous vessels and the enhancement of many details undetectable in conventional venograms.
authors.affiliation: Institute of Clinical Physiology, Biomedical Engineering Division, National Council of Research, 73100 Lecce, Italy. casciaro@ifc.cnr.it
authors.forename: Sergio
authors.initials: S
authors.lastname: Casciaro
authors.forename: Roberto
authors.initials: R
authors.lastname: Bianco
authors.forename: Roberto
authors.initials: R
authors.lastname: Franchini
authors.forename: Ernesto
authors.initials: E
authors.lastname: Casciaro
authors.forename: Francesco
authors.initials: F
authors.lastname: Conversano
mesh_terms: D000328:Adult; D001331:Automation; D001921:Brain / Q000098:blood supply* / Q000473:pathology*; D002550:Cerebral Veins / Q000473:pathology; D002560:Cerebrovascular Circulation; D003287:Contrast Media / Q000494:pharmacology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008962:Models, Theoretical; D016011:Normal Distribution; D019047:Phantoms, Imaging; D010690:Phlebography / Q000379:methods*
chemical_list: D003287:Contrast Media