[MR angiography of steno-occlusive lesions of intracranial arteries: a comparative study between turbo MRA and conventional MRA].
OBJECTIVE
To compare the quality and diagnostic accuracy of images of intracranial steno-occlusive lesions obtained by conventional MRA and turbo MRA reconstructed using the zero-filled interpolation technique in the slice-select direction.


METHODS
Eighteen patients with suspected steno-occlusive lesions of the intracranial arteries were studied with two types of three-dimensional time-of-flight angiography and conventional digital subtraction angiography. In total, 45 steno-occlusive lesions were quantitatively measured using calipers and correlated with DSA stenosis. A phantom that simulated vessels with stenosis was also imaged using the two types of MRA under the same conditions as those employed in the clinical study.


RESULTS
Compared with conventional MRA, turbo MRA reduced the jaggedness of vessels and offered appearances more similar to those of DSA in the antero-posterior and lateral views. The severity of stenosis was classified into five grades based on the percentage of occlusion: not significant (0-24%), mild (25-49%), moderate (50-74%), severe (75-99%), and occlusive (100%). Neither turbo MRA nor conventional MRA showed any discrepancy from DSA above grade-1 stenosis.


CONCLUSIONS
The advantage of turbo MRA is its ability to reduce the jaggedness of vessels on conventional MRA, and to simplify the recognition of vessel contours without prolonging acquisition time. Turbo MRA and conventional MRA have equally high diagnostic accuracy for steno-occlusive lesions.
Kominami
M
M
Department of Diagnostic Radiology, School of Medicine, Keio University Hospital.
Yamada
N
N
Imakita
S
S
Uchida
R
R
Kuribayashi
S
S
Kimura
K
K
Takamiya
M
M
D000368:Aged; D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D002539:Cerebral Arterial Diseases / Q000175:diagnosis*; D002536:Cerebral Arteries / Q000473:pathology*; D003251:Constriction, Pathologic / Q000175:diagnosis; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged