Gastric Artery Embolization with X-ray-visible Embolic Beads and C-arm Cone Beam CT for Increased Accuracy

1. Gastric Artery Embolization with X-ray-visible Embolic Beads and C-arm Cone Beam CT for Increased Accuracy Clifford R. Weiss MD1, Paul DiCamillo MD PhD2, Weijie Beh3,Tza-Huei Wang PhD4, Hai-Quan Mao PhD5, Dara L. Kraitchman VMD PhD2,6 • Radiology/Vascular and Interventional Radiology, The Johns Hopkins University School of Medicine • Radiology, The Johns Hopkins University School of Medicine • (3) Biomedical Engineering, The Johns Hopkins University School of Medicine • (4) Mechanical Engineering, The Johns Hopkins University Whiting School of Engineering • (5) Materials Science, The Johns Hopkins University Whiting School of Engineering • (6) Molecular and Comparative Pathobiology, The Johns Hopkins University School of Medicine

2. What you’ve just learned! No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

3. What you’ve just learned!

4. What you’ve just learned! Gastroenterology and Endoscopy News: April 2008 | v: 59:04

6. What you’ve just learned! Paxton et al, SIR 2012

7. Weight change after bariatric embolization (relative to untreated animals) % wt gain Week 4 Week 7 untreated % wt loss Bariatric embolization Paxton et al, SIR 2012

8. Challenges Facing Embolic Therapy • Complicated Vascular Anatomy • Non-target embolization to spleen / liver / esophagus / pancreas / intestine or “non-fundal” portions of stomach

9. Challenges Facing Embolic Therapy

10. Challenges Facing Embolic Therapy +

11. Challenges Facing Embolic Therapy BETTER SEE WHERE WE’RE GOING KNOW WHERE WE’VE BEEN

12. CT using Conventional Angiography C-arm Cone Beam CT (CBCT) • Flat panel • angiography • 8 s acquisition

13. Check Valve Prototype Microfluidic Device Barium-sulfate Alginate Oleic Acid Palginate>Pvalve>Poil Ca2+ Ca2+ Ca2+ Ca2+ Ca2+ IPA/ Ca Cl2 IPA/Ca Cl2

14. X-Ray Visible Embolic Beads (XEB)Microfluidic Device • Size determined by nozzle size & flow rate • Pressurized system prevents clogging of nozzles at high generation rates • Scale up by parallelization of device allows production of microbeads at rates of ~1 kHz.

15. SEM of XEBs

16. Fundal Anatomy and Arterial Map

17. Overall Approach • C-Arm Cone Beam CT (CBCT): • DynaCT: AXIOM ArtisdFA (Siemens Healthcare, Forchheim, Germany) • 8s DSA or DR, • 210° rotation, • 0.5°/ step, • contrast 25% iohexal Pre-embolization DSA CBCT Celiac DSA Directly Visualized Embo Repeat for each site Post-embolization CBCT DSA Pathology/Histology

18. Celiac Axis GACE 1, Series 3

19. “Fundal Branch” Embolization Pre-embolization Post-embolization

20. Beads are Visible During Delivery

21. “Fundal Branch” CBCTPre Contrast Post Sagittal Coronal Axial GACE 1, Series 7,19, 29

22. “Fundal Branch” CBCT Post Embolization

23. Left Gastric? GACE 1, Series 20, 21

24. Right Gastric Embolization Post Embolization Pre Embolization

25. Right Gastric CBCTPre Contrast Post SagittalCoronal Axial

26. Procedure Summary Pre Post “FB” Post RG SagittalCoronal Axial N= 3 swine

27. CBCT Post Embolization

28. Return to Site #2 to Find Left Gastric

29. Gross Pathology

30. Fundus 10x 2x

31. Body 2x 10x

32. Conclusions • Combination of XEB and CBCT allows the interventional radiologist to: • Better see where they are going • See where they have been • Allows for complete fundalembolization • Better assessment of treatment successes and failures • Should allow for “long term” • Allow Interventional Radiologist to determine if re-embolization is needed

33. Broader Implications • Not only promising for improving Bariatric Arterial Embolization (BAE/BE) • Current embolic therapy is growing market: • Hepatocellular Carcinoma • Other Tumors • Uterine Fibroids • Bronchial Artery Embolization