Takayasu arteritis :the role of MRI and MR angiography

Transcription

1 Takayasu arteritis :the role of MRI and MR angiography Poster No.: 427 Congress: ESCR 2013 Type: Poster Presentation Authors: A. Gyftopoulos, #. Georganas, E. DESPOTOPOULOS, N. Kiriakopoulos, G. Delimpasis; ATHENS/GR Keywords: Connective tissue disorders, Diagnostic procedure, MR, MRAngiography, Catheter arteriography, Vascular, Inflammation Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 22

2 Purpose To evaluate the role of MRI in Takayasu arteritis. To describe the best indications for MRI. To review the imaging findings. To review the basic concepts of Takayasu arteritis To describe the technique of three dimensional (3D) MR angiography and tissue characterization. To demonstrate the advantages of MR imaging over CT and conventional angiography in Takayasu arteritis. Takayasu 's arteritis is a chronic inflammatory and stenotic arteriopathy of medium and large sized arteries characterized by a strong predilection for the aortic arch and its branches. In 1908, Mikito Takayasu, a Japanese ophthalmologist, scientifically described the disease. It is a much less common disease than temporal arteriris with female preponderance. It usually occurs in adolescent girls and young women (80-90% of patients ). On the other hand it is the most common large vessel vasculitis of adolescence. It is neither racially nor geographically restricted(it is much more common in women and especially in those of oriental descent).ta is more common in Asian countries, but it has a worldwide distribution. The pathogenesis of the disease is unknown although an autoimmune reaction has been postulated.an association of the disease has been described with HLA-DR4 MB3 and with HLA-DR2, MB1. Infection has been considered to play a role in the pathogenesis with tuberculosis representing a possible etiologic factor, as well as viral and streptococcal infections. Histologically, TA is characterized by granulomatous inflammation of the arterial wall with marked intimal proliferation and fibrosis of the media and adventitia, which eventually leads to stenosis, occlusion, and, occasionally, poststenotic dilatations and aneurysm formation (when inflammation destroys the media). Methods and Materials Patients with confirmed Takayasu arteritis underwent MR angiography in our department. Page 2 of 22

3 The studies were performed on a 1.5-T MR unit (Siemens Sonata Maestro) with the use of body coil. Many patients had as well performed conventional angiography. The MR imaging techniques for evaluation of the disease include the following : 1. T2-weighted multiplanar sequences Fig. 3 on page 5. The entire aorta (from its root to bifurcation) is imaged in the axial or left anterior oblique-equivalent plane or both using the spin-echo or black blood technique. 2. Pre- and postcontrast T1-weighted turbo spin-echo (TSE) Fig. 5 on page 4 Fig. 6 on page MR angiography is used to evaluate luminal narrowing and dilatations using triggering technique (CARE BOLUS-SIEMENS). The contrast material used is gadolinium chelates. If MR angiography of the abdominal aorta is required, we obtain separate MR angiograms of the thoracic and abdominal aortas. The imaging time per measurement is seconds during a breath-hold. Cardiac gating was used in same cases. MR angiography includes : (a ) 3D angiography with contrast material (Gd) Fig. 9 on page 5 (b) and three-dimensional time-of- flight (TOF) Fig. 8 on page 3. TOF angiography without contrast material is not employed in thoracic and abdominal studies due to its limitations. 4.cine MRI 5. Phase contrast MRI at stenotic areas and cardiac valves. Images for this section: Page 3 of 22

4 Fig. 8: Time-of- flight (TOF) angiography without contrast material of the carotids and vertebral arteries. Fig. 6: Axial T1-weighted MR image (obtained before administration of gadolinium contrast) of a patient withtakayasu arteritis shows wall thickening of the ascending aorta. Page 4 of 22

5 Fig. 5: T1-weighted gadolinium-enhanced MR image of the same patient shows wall thickening and enhancement of the ascending aorta. Fig. 3: Axial T2-weighted MR image of the same patient shows wall thickening of the ascending aorta. Page 5 of 22

6 Fig. 9: Maximum intensity projection (MIP) 3D MR angiogram in a 48 years old female patient with Type IIa Takayasu arteritis shows almost occlusion of the left subclavian artery (thick arrow) 3 cm from its origin and high grade stenosis of the anonymous artery (brachiocephalic trunk) (thin arrow). Page 6 of 22

7 Results Clinical features Takayasu 's arteritis has generalized as well as local symptoms.the clinical manifestations are usually divided into early and late phases, with a classic triphasic pattern of expression.this consists of an early or prepulseless phase that includes fever, night sweats,fatigue, weight loss,myalgia and/or arthralgia and/or arthritis, skin rash (eg, erythema nodosum, pyoderma gangrenosum), headaches and/or dizziness and/or syncope,hypertension (wich may be paroxysmal). Pulses are commonly absent in the involved vessels, particularly the subclavian artery.next is a vascular inflammatory phase and a late quiescent and occlusive phase. A variable interval (months to years) may separate the acute from the occlusive phases. Characteristic features at the late phase include diminished or absent pulses, vascular bruits, hypertension (due to renal artery stenosis), cardiac involvement wich may include aortic regurgitation(when the ascending aorta is involved) and congestive heart failure resulting from myocarditis or increased afterload, neurologic symptoms,mesenteric angina and retinopathy. Clinically, hypertension, stroke, and aortic insufficiency warrant close attention, as these often lead to mortality. Takayasu 's arteritis has no specific markers.characteristic laboratory findings include elevated Westergren erythrocyte sedimentation rate, normochromic normocytic anemia in 50% of patients while acute phase reactants are elevated, with leukocytosis and thrombocytosis. Concentrations of C-reactive protein might be increased and the erythrocyte sedimentation rate might be accelerated, but they correlate poorly with disease activity. Classification The classification of the disease varies by several authors. Numano's group (1996) divided the disease into six types according to the site of involvement: Type I involves only the branches of the aortic arch. Type IIa involves the aorta only at its ascending portion involving or not the aortic arch with the rest of the aorta not affected. The branches of the aortic arch may be involved as well Fig. 1 on page 19. Type IIb affects the descending thoracic aorta +/- involvement of the ascending aorta or the aortic arch with its branches. The abdominal aorta is not involved. Page 7 of 22

8 Type III affects the descending thoracic aorta, the abdominal aorta, and/or the renal arteries Fig. 11 on page 16. Type IV involves only the abdominal aorta and/or the renal arteries. Type V combines features of the other types. Involvement of the coronary and pulmonary arteries should be indicated as C or P, respectively. Imaging studies ANGIOGRAPHY (Conventional or digital subtraction) Conventional angiography has been regarded as necessary for the diagnosis of TA and its complications. It shows surprising irregularity of the aorta, with the latter having similar appearance of an elderly atheromatous person. It has been the "gold" standard for the diagnosis and evaluation of Takayasu arteritis. It has certain drawbacks as the following: it is an invasive method with complication such as hematoma, vessel thrombosis,arteriovenous fistula and pseudoaneurysm. use of contrast media. requires high doses of ionizing radiation and has difficulties due to significant stenoses and/or calcification. it demonstrates only the appearance of the lumen and does not allow differentiation between active and inactive lesions; As a result imaging may be normal in cases of diffuse mural thickening without luminal changes (early phases). Some authors recommend total aortography for accurate estimation of disease extent. Magnetic resonance imaging, magnetic resonance angiography, computed tomography are useful for serial examinations and diagnosis in the early phase of TA. CT- CT angiography is useful for early diagnosis (wall thickening) and identifies cronic changes of the vessel( stenosis/occlusion) buthtere are also some contraindications limitations (iodinated contrast is limitited for allergic patients andthose with renal failure, radiation exposure, pregnancy, not good for follow up). Page 8 of 22

9 Magnetic resonance imaging and magnetic resonance angiography Fig. 12 on page 16 has certain advantantages: demonstrate mural thickening of the aorta Fig. 3 on page 13 Fig. 4 on page 13 demonstrate luminal narrowing Fig. 16 on page 19, use of contrast may reveal inflammatory lesions prior to the development of stenoses Fig. 5 on page 14 Fig. 6 on page 14 ( these lesions may be missed by angiography) not using nephrotoxic contrast media lack of ionizing radiation. paramagnetic contrast media rarely cause anaphylactic reactions and are nonnephrotoxic, and cine MRI depicts aortic regurgitation. At the same time MRI also has limitations : difficulty in visualizing small branch vessels poor visualization of vascular calcification. If visualization of small branch vessels or vascular calcification is important for decision making, additional examinations may be required. 3. MR angiography may accentuate the degree of vascular stenoses Aortic lesions including stenosis, dilatation, wall thickening, and mural thrombi are well visualized on MRI. Page 9 of 22

10 Fig. 1: Young female patient with Type IIb Takayasu arteritis. The right subclavian artery has stenotic segments (arrows). There are also some luminal irregularities References: RADIOLOGY, 251 HELLENIC AIR FORCE HOSPITAL - ATHENS/GR Page 10 of 22

11 Fig. 2: Maximum intensity projection (MIP) 3D MR angiogram shows irregularities and stenoses of the right subclavian artery. References: RADIOLOGY, 251 HELLENIC AIR FORCE HOSPITAL - ATHENS/GR The contraindications of MRI include the following : electronic devices which do not allow examination artifacts from surgical clips and metallic implants( pacemaker) longer examination times compared to CTA renal failure expensive claustrophobia Page 11 of 22

12 Image interpretation was done on a computer workstation. Source images were analyzed and postprocessing techniques were performed. The latter included MPR (multiplanar reformation), MIP (maximum intensity projection) Fig. 9 on page 15, and surface rendering (volume rendering) Fig. 14 on page 17 of the images. MIP images were the most widely used,as they allow 3D appreciation of vascular anatomy. Acute Phase Findings: wall thickening of the aorta and pulmonary artery (active inflammation) wall enhancement after gadolinium administration (active inflammation) occlusion of aortic or pulmonary artery branches may be seen rarely pseudoaneurysms Late Phase Findings: narrowing of the descending thoracic and abdominal aorta. Dilatation occurs most commonly in the ascending aorta aortic regurgitation caused by dilatation of the ascending aorta (Cine MRI) occlusion of aortic or pulmonary artery branches. They typically occur in the proximal portions of the branches. Stenosis involves all arteries arising from the aorta. The common carotid and subclavian arteries are most commonly involved. Occlusion is the second most common finding. Characteristic findings are abrupt occlusion and transition to collateral vessels as well as flame-shaped termination. In the abdominal aorta, the renal artery is the most frequently involved.pulmonary artery involvement is relatively high (occurrence rate of 50-80%) MR perfusion imaging can depict perfusion defects due to obstructive vessel changes Fig. 15 on page 18. Treatment Takayasu 's arteritis is a chronic relapsing disease. The course of the disease is variable with mortality statictics ranging from 10 (recent mortality figures) to 75%. Treatment of Takayasu arteritis may include: Corticosteroid medications to reduceinflammation Surgery to bypass narrow arteries MR and MRA is very usefull to therapy monitoring and should be used for follow up. Page 12 of 22

13 Images for this section: Fig. 3: Axial T2-weighted MR image of the same patient shows wall thickening of the ascending aorta. Page 13 of 22

14 Fig. 4: Sagittal T1-weighted MR image of a young female patient with Type IIa Takayasu arteritis shows wall thickening of the aortic arch Fig. 5: T1-weighted gadolinium-enhanced MR image of the same patient shows wall thickening and enhancement of the ascending aorta. Page 14 of 22

15 Fig. 6: Axial T1-weighted MR image (obtained before administration of gadolinium contrast) of a patient withtakayasu arteritis shows wall thickening of the ascending aorta. Fig. 7: Conventional angiography : Left subclavian artery has stenosis as well as some luminal irregularities. Images before and after angioplasty with good results. Fig. 9: Maximum intensity projection (MIP) 3D MR angiogram in a 48 years old female patient with Type IIa Takayasu arteritis shows almost occlusion of the left subclavian Page 15 of 22

16 artery (thick arrow) 3 cm from its origin and high grade stenosis of the anonymous artery (brachiocephalic trunk) (thin arrow). Fig. 10: MIP :The left subclavian artery is retrogradely filled by collateral vessels. Fig. 11: Sagittal 3D MR angiogram of a female patient shows a stenotic segment of the superior mesenteric artery (arrow) Page 16 of 22

17 Fig. 12: Coronal 3D MR angiogram shows wall thickening of the right subclavian artery wich has a stenotic segment. Page 17 of 22

18 Fig. 14: Volume Rendering: stenosis and irregularity of the left common carotid and subcluvian artery in a 57 years old female patient with Takayasu arteritis. Page 18 of 22

19 Fig. 15 Fig. 16 Page 19 of 22

20 Fig. 1: Young female patient with Type IIb Takayasu arteritis. The right subclavian artery has stenotic segments (arrows). There are also some luminal irregularities Page 20 of 22

21 Conclusion MR angiography is a very useful and reliable tool for the diagnosis and follow-up of Takayasu arteritis and can be used to guide treatment. References 1. Marcio V. Nastri, Luciana P. S. Baptista, Ronaldo H.,Baroni, Roberto Blasbalg Gadolinium-enhanced Three-dimensional MR Angiography of Takayasu Arteritis : RadioGraphics 2004; 24: Numano F, Okawara M, Inomata H, Kobayashi,Y. Takayasu's arteritis. Lancet 2000; 356: Johnston SL, Lock RJ, Gompels MM. Takayasu arteritis: a review. J Clin Pathol 2002; 55: Fauci A,Braunwald E, Isselbacher K, Wilson J. Harrison 's Internal Medicine;14th ed:1918, Sheikhzadeh A, Tettenborn I, Noohi F, Efterkharzadeh M, Schnabel Occlusive thromboaortopathy (Takayasu disease): clinical and angiographic features and a brief review of literature. Angiology 2002; 53: Moriwaki R, Noda M, Yajima M, Sharma BK, Numano F. Clinical manifestations of Takayasu arteritis in India and Japan: new classification of angiographic findings. Angiology 1997; 48: Choe YH, Han BK, Koh EM: Takayasu's arteritis: assessment of disease activity with contrast- enhanced MR imaging. AJR Am J Roentgenol 2000; 175: Kumar S, Radhakrishnan S, Phadke RV: Takayasu's arteritis: evaluation with threedimensional time-of-flight MR angiography. Eur Radiol 1997; 7(1): Park JH, Chung JW, Im JG, Kim SK, Park YB, Han MC. Takayasu arteritis: evaluation of mural changes in the aorta and pulmonary artery with CT angiography. Radiology. 1995;196: Desai MY, Stone JH, Foo TKF, et al. Delayed contrast-enhanced MRI of the aortic wall in Taka yasu's arteritis: initial experience. AJR 2005; 184: Page 21 of 22

22 11. Eijun Sueyoshi1, Ichiro Sakamoto1 and Masataka Uetan MRI of Takayasu's Arteritis: Typical Appearances and Complications AJR 2006;187;6 Personal Information Gyftopoulos Anastasios Consultant Radiologist 251 Hellenic Air Force Hospital MRI Department tassosg@hotmail.com telephone: Page 22 of 22