Comparative Study Of MRA And DSA In The Dioagnosis Of Cerebrovascular Diseases

ObjectiveWith the development of medical imaging technology, there are notable increase in diagnostic accuracy and curative ratio on cerebrovascular diseases. Now days, the conventional medical imaging technology for cerebrovascular diseases are magnetic resonance angiography (MRA)(TOF, PC, CE), digital subtraction angiography (DSA), computed tomography angiography(CTA), transcranial color-coded duplex sonography (TCCS). However, doctors pay more and more attention to the chose of economic imaging modality. In this article, We compared the application of MRA (TOF, PC) and DSA in the dioagnosis of cerebrovascular diseases, to evaluate the advantage and disadvantage of MRA and DSA techniques in displaying cerebrovascular diseases, So that can help doctors to choose the best imaging modality and achieve the best effect on cerebrovascular diseases.MethodsSixty patients (40 male,20 female) who were treated in interventional therapy department from June,2009 to December,2009 were enrolled. The mean age of patients was 44 years(range:21 to 67 years). All of them were given both MRA and DSA examination. The mean interval of the two examination is 2 days(range lto 3 days).MRA was performed on a Signa EXCITE TwinSpeed 1.5THD MRI (Magnetic Resonance Imaging) system (GE,USA), with unenhanced TOF (time-of-flight) (2D, 3D), and PC (Phase Contrast) (2D,3D) methods to follow cerebral artery and brain vein imaging. After acquisition, three-dimensional maximum intensity projections (MIP) were reconstructed, regions of interest were also reconstructed for MRA evaluations.DSA (AXIOM Artis dTA, SIEMENS) was performed via the femoral artery, starting with imaging of the aortic arch followed by selective injections of contrast agent into both carotid and vertebral arteries. DSA was performed in the anteroposterior, lateral and oblique projections. Non-ionic contrast (Iohexol) was administered with a power injector. No DSA related complications were reported. All subjects were fasted at least 6 hours before contrast injection, and iodine allergy test were negative.ResultsMRA TOF and PC examination make coinciding visualization and characterization with DSA in 39 cases of cerebral artery stenosis patients and four cases of cerebral aneurysm patients;TOF-MRA at 1.5T detected one patient was cerebral arteries stenosis with pseudoaneurysm, after the 3D-DSA rotational radiography of the same case, only cerebral arteries stenosis was seen, but there is no an aneurism. In 2 internal carotid artery stenosis patients, MRI detected infarcted nidus but MRA TOF and PC examination did not show stenosis in the beginning of internal carotid artery because we could not scan them; There were 4 AVM (arteriovenous malformation) patients. Image quality of TOF-MRA at 1.5T was superior to DSA in detecting superficial and deep draining veins and small veins. Evaluation of feeding arteries and cerebral arteriovenous malformation was equally good at DSA and 1.5T TOF-MRA; Two cases of venous sinus thrombosis were showed by both DSA and TOF, But thrombosis were not detected by PC due to artifacts. One case of venous malformation was detected by all the three imaging modalities. All the cerebrovascular imaging diagnosis were confirmed by interventional therapy. MRA TOF and DSA show arteries more clear than MRA PC, but not as good as PC in display venous。ConclusionMRA (TOF and PC)is an economy, convenient, reliable noninvasive medical imaging technology for cerebrovascular diseases. Since it is high definition for soft tissue, it plays very important role in the diagnosis for cerebral venous sinus occlusive diseases. TOF-MRA is superior to DSA in detecting cerebral venous diseases and the three-dimensional structure and shape of aneurismal. In conclusion, MRA and DSA can be complementarily combined use in the diagnose and differential diagnosis, follow-up, detecting nidus distribution of cerebrovascular diseases.