Diagnostic quality and accuracy of low dose 3D-DSA protocols in the evaluation of intracranial aneurysms.
BACKGROUND
3D-DSA is the 'gold standard' imaging technique for the diagnosis and characterization of intracranial aneurysms.


OBJECTIVE
To compare the image quality and accuracy of low dose 3D-DSA protocols in patients with unruptured intracranial aneurysms.


METHODS
The standard manufacturer 5 s 0.36 μGy/f protocol and one of three low dose 3D-DSA protocols (5 s 0.10 μGy/f, 5 s 0.17 μGy/f, 5 s 0.24 μGy/f) were performed in 12 patients with unruptured intracranial aneurysms. Three interventional neuroradiologists, two neurosurgeons, and two neurologists rated the image quality of all 3D reconstructions as good, acceptable, or poor. Three interventional neuroradiologists measured two dimensions of each aneurysm for all protocols. The radiation dose metric Ka,r (reference point air kerma, in mGy) was recorded for each 3D-DSA protocol.


RESULTS
The standard 5 s 0.36 μGy/f protocol earned the highest average subjective rating of 2.76, followed by the 5 s 0.24 μGy/f (2.72), and 5 s 0.17 μGy/f (2.59) protocols. The ranges of differences in aneurysm measurements between the 5 s 0.24 μGy/f protocol and the standard were <0.5 mm. The median Ka,r metrics for each protocol were as follows: 5 s 0.36 μGy/f (89.0 mGy), 5 s 0.24 μGy/f (57.7 mGy), 5 s 0.17 μGy/f (45.9 mGy), and 5 s 0.10 μGy/f (27.6 mGy).


CONCLUSIONS
Low dose 3D-DSA protocols with preserved image quality are achievable, and can help reduce exposure of patients and operators to unnecessary radiation. The 5 s 0.24 μGy/f protocol generates one-third smaller radiation dose than the standard 5 s 0.36 μGy/f protocol without compromising diagnostic image quality or accuracy.
Division of Interventional Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Monica S
MS
Pearl
Division of Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Collin
C
Torok
Division of Interventional Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Zinovy
Z
Katz
Division of Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Steven A
SA
Messina
Neurointerventional Department C.D.I, Hospital Clinic of Barcelona, Barcelona, Spain.
Jordi
J
Blasco
Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Rafael J
RJ
Tamargo
Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Judy
J
Huang
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Richard
R
Leigh
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Steven
S
Zeiler
Division of Interventional Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Martin
M
Radvany
Siemens Corporate Research, Baltimore, Maryland, USA.
Tina
T
Ehtiati
Division of Interventional Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Philippe
P
Gailloud
D000328:Adult; D015901:Angiography, Digital Subtraction / Q000592:standards*; D002533:Cerebral Angiography / Q000592:standards*; D002985:Clinical Protocols / Q000592:standards*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000592:standards; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D011829:Radiation Dosage
Aneurysm; Angiography; Technique