1/30/2014. MRA Verses CTA In Detecting Vascular Abnormalities BONNIE VAN MAANEN RT(CT) (BS) (MBAHC) MRA/CTA Objectives. A True Cat Scan MRA VS CTA

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1 MRA Verses CTA In Detecting Vascular Abnormalities A True Cat Scan BONNIE VAN MAANEN RT(CT) (BS) (MBAHC) MRI SCANNER MRA VS CTA CT SCANNER MRA/CTA Objectives * The objectives in this presentation is to introduce varieties of techniques and procedures in detecting vascular abnormalities with MRA and CTA, and how arterial opacification is inversely related to the patient s body weight and cardiac output. There will be a brief overview on MRA and CTA contrast administration and how to overcome IV and timing issues. The underlying principles behind the use of IV contrast rate and scan protocols for MRA and CTA s, including injecting duration, scan time, inherent delay and diagnostic delay MRA/CTA * CTA is special CT imaging of the blood vessels. Utilizing the high resolution imaging of CT and the enhancing qualities of intravenous (IV) contrast, CTA provides unparalleled views of the blood vessels in a noninvasive manner, such as the cardiac arteries, aorta, abdominal arteries, lower extremity arteries, or lung arteries. * MRA is a group of techniques base on magnetic resonance imaging to image blood vessel. * MRA has been less successful then CTA in evaluating the coronary arteries. MRA VERSES CTA MRA and CT Angiography are performed to visualize the vessels and arteries to detect any abnormalities in an none invasive way. MRA and CTA provides excellent pre-procedural workup, which is implemented as a two-dimensional or a three dimensional (3D) acquisition. There are two main classes of angiograms, including "Catheter" Angiograms and CT or MRI Angiograms. Successful MRA/ CTA studies depends on the quality of contrast enhancement. In order to provide high quality imaging studies; one must remember basic contrast administration principles to achieve best results. 1

2 Advantage And Disadvantages CTA are superior to MRA CTA is quicker than MRA All CTA requires contrast MRA can be done without contrast Coronary arteries are visualize best with CTA MRA cannot capture images of calcium deposit MRA could be difficult to separate arteries from veins MRI/ MRA VERSES CT/CTA MRI/MRA MORE OPTIONS FOR IMAGE CONTRAST (EG, DWI) BETTER FUNCTIONAL IMAGING OPTIONS NO IONIZING RADIATION BETTER WITH SOME HARDWARE (EG, ANEURYSM COILS) LESS SENSITIVE TO CALCIFICATION/OSSIFICATION CT/CTA FASTER 24/7 AVAILABILITY UNSTABLE PATIENTS, PACEMAKERS OR OTHER MR CONTRAINDICATIONS, ETC. BETTER WITH SOME HARDWARE (EG, TITANIUM CLIPS) BONE DEPICTION, LANDMARKS CTA/MRA PECTUS EXCAOATUM PECTUS EXCAOATUM MITRAL VALVE PROLAPSE Mitral valve prolapse is a disorder in which, during the contraction phase of the heart, the mitral valve does not close properly. When the valve does not close properly it allows blood to backflow into the left atrium. Some symptoms can include palpitations, chest pain, difficulty breathing after exertion, fatigue, cough, and shortness of breath while lying down. 2

3 VALSALVA SINUS ANEURYSM Nonruptured Valsalva Sinus Aneurysm Normal Valsalva sinuses. (a) Thin-section maximum intensity projection (MIP) image of the heart (three-chamber view) obtained at ECG-gated CT shows the left ventricular outflow tract, the valve commissures (white arrow), and the sinotubular junction (black arrows). Sov = Valsalva sinuses. (b) Oblique axial thinsection MIP image obtained at ECGgated CT at the level of the aortic valve shows the Valsalva sinuses and the coronary arteries. LCC = left coronary cusp, NCC = noncoronary cusp, RCC = right coronary cusp. FINDINGS AT CT AND MR IMAGING Nonruptured Valsalva sinus aneurysm in an asymptomatic 80-year-old man with heart murmur. Oblique axial (a) and oblique coronal (b) thick-slab volumetric reconstructions obtained at ECG-gated CT and oblique axial thin-section MIP image (c) obtained at the level of the sinuses show a nonruptured 2.4-cm Valsalva sinus aneurysm (arrows). In b, the aneurysm is seen arising from the right coronary sinus and extending into the right ventricle (RV). The origin of the right coronary artery is seen distal to the aneurysm, which arises near the level of the sinotubular junction (arrowhead in a and b). LV = left ventricle. VALSALVA SINUS LEAK Nonruptured Valsalva sinus aneurysm in an 80-year-old man with chest pain and diaphoresis. (a, b) Oblique coronal (a) and oblique axial (b) balanced SSFP MR images show a 6.7-cm aneurysm (arrows) originating from the right coronary cusp and extending toward the right ventricle. (c, d) Axial contrast-enhanced ECG-gated CT images, obtained with soft-tissue window settings (c) and narrowed softtissue window settings (d), 3 days after patch repair, show a small leak of contrast material (arrowhead in d) extending into the aneurysm (arrows). AAA ENHANCED SPIRAL CT SCANS WITH MULTIPLANAR RECONSTRUCTION AND A CT ANGIOGRAM. CT 3D OF AAA Endovascular AAA Repair 3

4 Endovasular Ruptur Peripheral Emboli And Claudication AKA: Blue Toe Syndrome Abdominal Aortic Aneurysm Magnetic Resonance Angiogram (MRA) Of Vessels COURTESY OF INTERMOUNTAIN MEDICAL IMAGING, BOISE, IDAHO. FIGURE 1 AND FIGURE 2 SHOW THE NORMAL SMOOTH APPEARANCE OF THE LARGE BLOOD VESSEL (AORTA) THAT CARRIES BLOOD FROM THE HEART. FIGURE 3 SHOWS A NARROWED AND ABNORMAL AORTA FROM THE BUILDUP OF CALCIUM AND FAT (CHOLESTEROL) IN THE INNER LINING OF THE ARTERY, OFTEN CALLED "HARDENING OF THE ARTERIES" (ATHEROSCLEROSIS). CTA SADDLEBACK EMBOLISIZIMS *OBSTRUCTIVE SUBCLAVIAN *COLLATERAL VESSELS 4

5 MRA ABDOMEN-MESENTERIC ISCHEMIA MRA ABDOMEN-MESENTERIC ISCHEMIA MRA NECK Intracranial Bleed (Aneurysms) 50% -70% intracranial bleeds are from aneurysms 15% with SAH die before reaching hospital Remainder rebleed -20% rebleed within 2 weeks - 30% rebleed in a month -40% rebleed by 6 month Rebleed is associated with a mortality rate of 40% MRA HEAD NON CONTRAST STUDY 5

6 Dissection Of The Extracranial Arteries ACCOUNTS OF THE EXTRCRANIAL ARTERIES ACCOUNTS FOR 10%-25% STROKES COULD BE TRAUMATIC OR SPONTANEOUS COULD LEAD TO STROKE CTA VISUALIZED CERVICAL ARTERY DISSECTION THAN MRA MRA VISUALIZES ICA CT Angiography And MR Imaging Of Cervical Artery Dissection RIGHT VERTEBRAL ARTERY DISSECTION CT/CTA And MR Imaging/MRA Of A Left ICA Dissection CT/CTA Imaging Of Multivessel Dissection (Right ICA And VA) CTA HEAD AWI STATION MRA CTA HEAD MRA HEAD COW 6

7 CT NECK WITH IV CONTRAST VALSALVA EFFECT SVC AND AORTA NO CONTRAST IN PULMONARY-DENSE CONTRAST IN SVC AND AORTA LEFT HEART DENSE CONTRAST PULMONARY NO CONTRAST IN THE PULMONARY ARTERIES AND RIGHT HEART CONTRAST ADMINISTRATION Scan Protocal 7