title: Hybrid of opposite-contrast magnetic resonance angiography of the brain by combining time-of-flight and black blood sequences: its value in moyamoya disease.
abstract: OBJECTIVE
  We assessed the value of a new magnetic resonance angiography (MRA) technique named hybrid of opposite-contrast (HOP) MRA in the diagnosis of moyamoya disease.
  
  
  METHODS
  Using a dual-echo sequence, we obtained the first echo for time-of-flight (TOF) MRA followed by the second echo for black blood MRA. We then subtracted the black blood MRA data set from that of the TOF MRA followed by maximum-intensity projection. In 14 patients, we performed HOP MRA and compared the findings with those on 3-dimensional TOF MRA and MR images. The HOP MRA was also compared with a radionuclide perfusion study (7 patients).
  
  
  RESULTS
  The HOP MRA technique improved the demonstration of distal arteries in 13 patients. The findings in HOP MRA correlated with MR images in 9 patients as well as with the perfusion study in 6 patients.
  
  
  CONCLUSIONS
  The HOP MRA technique demonstrated the distal arterial branches in moyamoya disease well and facilitated the perfusion assessment with MR imaging.
authors.affiliation: Department of Radiology, Kyorin University Faculty of Medicine, Tokyo, Japan. tsuchiyak-kyr@umin.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Maiko
authors.initials: M
authors.lastname: Yoshida
authors.forename: Masamichi
authors.initials: M
authors.lastname: Imai
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Nitatori
authors.forename: Tokunori
authors.initials: T
authors.lastname: Kimura
authors.forename: Masato
authors.initials: M
authors.lastname: Ikedo
authors.forename: Shuhei
authors.initials: S
authors.lastname: Takemoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply*; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D015899:Tomography, Emission-Computed, Single-Photon