Non-Cardiovascular Findings on CMR

1. A major teaching hospital of Harvard Medical School Non-Cardiovascular Findings on CMR Marty Smith M.D. Instructor in Radiology Beth Israel Deaconess Medical Center Harvard Medical School Boston, MA

2. Objectives • Review data for incidental non-cardiovascular findings (NCF) in cross-sectional cardiac imaging • Approach to non-cardiovascular structures on CMR imaging • Overview of common lesions and their expected appearance on CMR

3. What is covered? Imaged volume – Base of Neck → Kidneys Base of Neck - Thyroid, parathyroid, trachea, esophagus, muscles, vertebral bodies, lymph nodes, nerves, fat Thorax • Thyroid • Mediastinum – thymus, trachea & bronchi, esophagus, vertebral bodies, spinal canal, lymph nodes, nerves, fat • Lungs and pleura • Chest wall – bones, muscles, lymph nodes, nerves, fat • Breasts • Diaphragm

4. What is covered? Abdomen • Liver • Gall bladder and bile ducts • Pancreas • Kidneys • Adrenal Glands • Spleen • Stomach • Bowel and Mesentery • Vertebral column, nerves, spinal canal, paravertebral musculature, fat, fascia, & lymph nodes

5. Background: Non-Cardiac Findings Dewey M, et al. Non-cardiac findings on coronary computed tomography and magnetic resonance imaging.Eur Radiol 2007 Feb 1; [Epub ahead of print]. • 108 consecutive patients suspected of having CAD who had CTA & MRA • Significant NCF → clinical or radiology F/U • CT – 5 (5%) significant non-cardiac findings • PE, pleural effusion, sarcoid, HH, & pulmonary nodule • MRI – 2 (2%) significant non-cardiac findings • Pleural effusion & sarcoid – both seen on CT

6. Non-Cardiac Findings Of 108 pts. Dewey at al. Eur Radiol 2007 Conclusion: Incidental NCF are common; images should be analyzed by radiologists to ensure findings not missed & unnecessary follow-up avoided.

7. Non-Cardiac Findings on Cardiac CT • Cardiac MDCT in 503 pts1 • 346 new NCF in 292 pts (58.1%) • 114 pts (22.7%) had clinically significant findings • 4 cases of malignancy (0.8%). • 49 lung nodules <1cm (12 > 1cm), 8 aortic,17 pleural effs • Cardiac MDCT in 166 pts, suspected CAD2 • NCF in 41 pts (24.7%), major (4.8%) • EBCT in 1326 pts for coronary Ca2+ scoring3 • NCF requiring f/u in 103 pts (7.8%) • EBCT in 1812 consecutive pts4 • NCF in 630 (35%); 50 (2.8%) f/u imaging • Summary for CT: • NCF in 24-58% • NCF needing f/u in 2-23% • Classification criteria variable 1 Onuma Y, et al. J Am Coll Cardiol 2006 2 Haller S, et al. AJR Am J Roentgenol; 2006 3 Horton KM, et al. Circulation 2002 4 Hunold P, et al. Eur Heart J 2001

8. BIDMC CMR Experience – Part I • 1534 clinical CMR reports reviewed 2002-061 • 129 NCF in 116 (8.2%) studies • 55 “major” findings in 50 (3.3%) studies • lymphadenopathy - 22 (1.4%) • lung abnormalities - 19 (1.2%) • mediastinal masses - 6 (0.4%) • breast lesions - 4 (0.3%), ascites - 3 (0.2%), soft tissue masses - 1 (0.1%) • 74 “minor” findings in 70 (4.6%) studies • pleural effusions, liver lesions, renal cysts, HH, diaphragmatic abnormalities, splenic abnormalities, paraspinal lipomas, & anomalous vasculature • NCF mean age 54 vs 49 w/o (p <0.001) 1 Chan PG, etal. JACC 2009

9. BIDMC CMR Experience – Part II • 495 clinical CMR exams in 2006 reviewed for NCF by radiologist w/o prior readings • NCF classification • Benign (gynecomastia, simple cyst) • Indeterminate (pleural effusion, liver & renal lesions) • Worrisome (lung nodules) • Follow-up of indeterminate & worrisome NCF using Careweb • New vs known abnormality • What follow-up performed

10. Results: NCF Prevalence • 295 NCF in 212 / 495 (43%) studies • 144 Benign: 123 / 495 (25%) studies • 137 Indeterminate: 105 / 495 (21%) studies • 14 Worrisome: 14 / 495 ( 3%) studies Benign: Gynecomastia (41), HH (22), Renal Cyst (17), Liver cyst/hemangioma (16), Scoliosis (11), Mediastinal LAN <1.5 cm (10), Other (27) Indeterminate:Pleural effusion (29), Renal lesion (27), Atelectasis (11), Mediastinal LAN >1.5 cm (11), Lung consolidation (7), Big HH (6), Liver lesion (6), Other (40) Worrisome:Lung nodules (11), Aortic dissection (1), Aortic ulcer (1), Mediastinal mass (1)

11. Results: NCF Detection & F/U • 105 / 295 (36%) NCF listed in clinical report • Benign (21%), Indeterminate (50%), Worrisome (50%) • 11 NCF in reports missed by reviewer • 65 NCF in 52 pts needed f/u → performed on 25 (38%)* • Of NCF reported, 22 needed f/u → performed on 12 (55%)** * No online medical record information currently available for pts with 16 findings ** No online medical record information currently available for pts with 7 findings

12. Known Follow-up Management changing findings in 11 pts: • Lung cancer (2) • Pulmonary nodule requiring further follow-up (2) • Typical pulmonary carcinoid • Cryptogenic organizing pneumonitis (COP) • Multifocal pneumonia secondary to newly diagnosed AML • Mediastinal lymphadenopathy requiring further follow-up • Breast implant rupture • Obstructed atrophic kidney • New AAA (previously repaired but with recurrence)

13. Results: Radiologist’s Presence • Radiologist at joint read-out – 384/495 (78%) scans • 42% (95/228) of NCF reported when radiologist at joint readout • 15% (10/67) of NCF reported when radiologist read remotely (p<0.01)

14. Results: Sequences • Scouts showed NCF 186/295 (63%) • T1W FSE showed NCF 176/295 (60%) • Only 12 (4%) NCF not visualized on one of these sequences • 10 benign, 2 indeterminate)

15. CMR Sequences

16. CMR Sequence Overview • Abdomen & base of neck • FFE scouts • Limited coverage by other sequences • Thorax – Potentially all sequences • Most →T1-w TSE, FFE scouts, B-FFE cines • Other T1-w imaging • T1-w TSE FS • Post gado T1-w TSE, T1-w IR GRE, T1-w SPGR • T2-w imaging • T2-w TSE dark blood • Fat suppressed T2-w → SPIR, STIR

17. FFE Scouts • Limited soft tissue lesion detection & characterization • Large inter-slice gap, low resolution • Contrast based on T2/T1 ratio • Bright = Fluid or fat • Not bright = Soft tissue, some complex fluid • Motion insensitive • Shape & margin with well defined lesions • Internal structures of cysts • B-FFE and TFE similar for NC lesions

20. TSE T1 • True T1-weighted sequence with IR blood suppression • Bright – fat, hemorrhage, protein, some flow, some Ca2+ • Dark – Simple fluid, most Ca2+, air • In-between – most masses • Cover from top of liver to above arch • Excellent for anatomy • Best look at mediastinum, breasts, chest wall, lungs • Navigator problematic around diaphragm • More helpful when combined with T1 FS

22. FFE & TSE T1 • Most commonly see lesions on T1 & FFE Fat, Hemorrhage Hemorrhage, Protein Soft Tissue Cyst

23. Other T1 Weighted Sequences • T1-w TSE with fat saturation • Identify fatty lesions definitively • Increased conspicuity of T1 bright lesions • Post gadolinium – Tissues vs fluids (inflammation, atelectasis, infarcts) • T1-w TSE → less conspicuity of enhancement • T1-w FS SPGR → usu. early; best for enhancement • T1-w IR GRE → Delayed; caveat of IR • Subtractions helpful for intrinsic T1 bright lesions

25. T2 Weighted Imaging • T2-w TSE – True T2-w sequence • STIR –T1-w & T2-w; good fat suppression • SPIR – True T2-w; less homogeneous fat suppression • Bright on FFE & T2-w TSE • Cysts, hemangiomas, fat, some hemorrhage • Mildly bright on T2-w TSE → Usu. concerning • Increased brightness with SPIR, STIR • Fibrous tumors (eg, breast ca) still dark

26. T2-w TSE SPIR

27. Big Picture • Brighter lesion on FFE, T1-w TSE, or T2-w TSE → More likely it’s benign • Look for subtle nodularity, esp. with hemorrhage • No gadolinium → f/u imaging or not? • Well seen, sharp margin, homogeneously bright on FFE or T2-w TSE, not bright on T1-w TSE → Benign → Stop • Except breast • Not well seen, irregular margin, heterogeneous, bright on T1(& not fat), not bright on T2-w TSE → f/u imaging • Enhancement→ Usu. f/u imaging for further characterization or diagnostic procedure

28. Big Picture • Need to look separately for NCF • Develop a system • If you aren’t looking for it, you won’t see it • Symmetry is your friend • Use cross referencing tools • The only thing better than your MR . . . is an old MR (or CT)

29. Lesions by Location

30. Mediastinum Diversion Old Radiology • Anterior Mediastinum – posterior to sternum, anterior to trachea & posterior aspect of heart • thymus, lymph nodes, nerves, fat • Middle Mediastinum – b/w anterior & posterior mediastinum • trachea & bronchi, esophagus, lymph nodes, nerves, fat • Posterior Mediastinum – b/w posterior chest wall & 1 cm behind anterior margin of vertebral column • vertebral bodies, spinal canal, lymph nodes, nerves, fat

31. Cross Sectional Mediastinum • Differential based on tissue where mass arises • If not possible, then localize by region • Supraaortic mediastinum (superior mediastinum) • Prevascular space, Anterior cardiophrenic angles • Pretracheal & subcarinal spaces, AP window • Paraesophageal or azygoesophageal recess • Paravertebral • Caveat: Be sure it is from the mediastinum • Deep to vessels → Definitely • Broad Base, smooth margin; not spiculated or irregular

32. Lymph Nodes • Every site in mediastinum • Lymphoma, Mets, Sarcoid, Granulomatous Infxn • Pattern can be important • Symmetric bilateral hilar & paratracheal – likely sarcoid • Prevascular nodal mass – Hodgkin’s Lymphoma > NHL • Unilateral hilar +/- paratracheal – Lung > other mets • Posterior mediastinum – Lymphoma (NHL) vs mets • Cardiophrenic angle – Mets vs lymphoma • Intermediate T1, bright T2, enhancement • Necrosis – Mets, lymphoma (NHL) ,Tb, fungus • Ca2+ – Granulomatous infxn, sarcoid; treated lymphoma

33. Hodgkin’s Lymphoma

35. Sarcoid

37. RCC Mets

38. Chloroma

39. Thyroid Lesions • Supraaortic Mediastinum • Can extend into prevascular space, around trachea • Goiter • Bland Goiter – Low SI T1-wi & intermediate SI T2-wi • Multinodular Goiter – Heterogeneous on T1-wi & T2-wi • Thyroid Cancer • Can be invasive, but usually not • Carcinoma in multinodular goiter – 7.5 % • MRI can not definitively differentiate benign & malignant

40. Thymus & Thymic Masses • Prevascular Space • Normal thymus • Fat proportion increases with age → harder to see • Intermediate on T1-w, bright on T2-w; margins important; interdigitating fat • Thymic rebound– stress (chemo, burns) • Thymoma – # 1 adult 1° mediastinal tumor • Variable; homogeneous, cystic, nodules; invasion • Thymolipoma; thymic cyst, carcinoma, carcinoid; lymphoma, mets

41. Normal Thymus

42. T1-w TSE SPIR

43. Foregut Cysts • Bronchogenic – Most common • Any location – 50% subcarinal, 20% paratracheal • Rounded, smooth, sharply defined (imperctible wall) • Fluid contents variable • Pericardial • 90% touch diaphragm, 65%R 35%L cardiophrenic angle • Usually simple fluid, sometimes hemorrhage • Esophageal duplication • Neurenteric • Associated vertebral anomaly

46. Germ Cell Tumors • Anterior Mediastinal Mass (prevascular) • More in young adults; 80% benign • Teratomas • All germinal layers • Cysts, fat (Fat-fluid levels), Ca2+, soft tissue • Seminomas • Men; most common malignant GCT; homogeneous • Nonseminomatous GCT • Rare, heterogeneous

47. Hernias • Hiatal • Sliding (most common), Paraesophageal, Mixed • Bochdalek • Posterolateral and left more common • Retroperitoneal fat, rarely kidney or liver • Morgagni • Anteromedial • Omental fat (Pseudomass), Transverse Colon • Traumatic Diaphragmatic • Small at inception → grow latently

49. Esophagus • Thickening • Esophagitis, Barrett’s, cancer • Mass • Leiomyoma, lipoma, cancer

50. Paravertebral Region • Neurogenic Tumors • Nerve Sheath (Schwannomas), sypmathetic ganglia tumors, paragangliomas • Commonly bright on T2, avidly enhancing • Thoracic Spine abnormalities • Fractures, Malalignment, DDD, Hemangiomas, Tumors • Meningoceles and nerve sleeve cysts • Extramedullary hematopoesis • Multiple bilateral paravertebral tumors, hyperenhance • Nodes are still most common