Spherical Embolics: So Many Choices, So Little Time

GEST 2016 US, New-York
Spherical Embolics:
So Many Choices So Little Time
Jean-Pierre Pelage, MD PhD
[email protected]
Jean-Pierre Pelage, M.D., Ph.D.
• Consultant/Advisory Board: Merit Medical,
Terumo, ALN, Cook Medical,Guerbet, Boston
Scientific
• Research Grants: BTG, Terumo, ALN
Embolic Microspheres (Non resorbable)
Calibrated microspheres
Allow targeted devascularization / occlusion
Injectable through microcatheters (even large sizes)
Different presentations: visible, syringe, …
Different properties
Specific instructions for use
How to make your choice?
Embolization Microspheres
Embozene
Hydropearl
Presentation
• Prepacked syringes (1 or 2 mls) vs vials
• Visible:
- blue: Bead Block
- transparent: Embosphere (purple: EmboGold)
- color-coded by size: Embozene or Hydropearl
• Calibration (granulometric distribution):
- Range of sizes (300-500 µm): Bead Block and
Embosphere
- Narrow calibration (600 µm): Embozene and Hydropearl
Granulometric Distribution
700-900 µm Product A
Characteristics
• Compressibility = ability to be compressed (microcatheter,
vessel)
Compressibility > 30% = ability of 700-900 µm
microspheres to be injected through a >.025 ID microcatheters
>30% risk of rupture except soft microspheres
• Elastic recovery = time required to get back to its initial
spherical shape
Slow recovery = distal traveling
Compression / Decompression Test
Before compression
Soft product
Rigid product
30% compression
Sudden Release
Tris-Acryl Microspheres
Embosphere,
Merit Medical (Biosphere Medical)
Mechanisms of Occlusion
Spherical particles
No aggregates
Complete lumen occlusion
Various Clinical Indications
and Long-Term Tolerance
1 year
Facial AVM
6 years
Intravascular Location of Embolic Particles
Pre-operative Embolization of Meningiomas
70%
60%
50%
40%
MS 100-300µm
30%
PVA 45-150µm
PVA 150-250µm
20%
10%
0%
absent
arteriolar
capillar
Bendszus. AJNR 2000;21:255-61
600
500
400
300
200
100
ES 700/900
ES 500/700
ES 300/500
0
ES 100/300
Diameter of arteries (µm)
Embolization of the Sheep Uterus
Diameter of occluded arteries (µm)
Pelage, et al. Radiology 2002;224:436-45
Acrylamido-PVA microspheres
Bead Block, BTG (Biocompatibles)
Compressibility Evaluation (900-1200µm)
(Mean SD - 5 samples)
Force (g)
40
Embosphere
35
30
25
20
BeadBlock
15
10
Contour
5
0
0%
10%
20%
30%
40%
50%
-5
Déformation (%)
60%
70%
80%
Acrylamido-PVA Microspheres
• Bead Block 700-900 µm is equivalent to
500-700 µm tris-acryl microspheres
PMMA hydrogel with polyzene F coating
Embozene, Boston Scientific (Celonova)
Embozene
Embozene
Embozene
•
•
•
•
•
Non-resorbable
Spherical
Compressible
• Very compressible
Easy to inject (microcatheter)
• Specific technique of use
Very narrow calibration (600µm
≠ tris-acryl MS
≠ 500-700 µm)
• Secondary redistribution
• Microspheres color-coded
Deformation Embosphere vs Embozene
Embozene
Embosphere
Top Tips
Because more compressible than
Embospheres, consider upsizing for safety
i.e. Embozene 900 µm recommanded for
uterine fibroid embolization
Secondary redistribution more significant
PolyEthlyleneGlycol (PEG) Microspheres
Hydropearl, Microvention-Terumo
Hydropearl
400µm
800µm
75µm
200µm
600µm
1,100µm
Hydropearl
•
•
•
•
•
Non-resorbable
Spherical
Compressible
• Compressibility?
Easy to inject (microcatheter)
• 800 µm recommanded
Very narrow calibration (600µm
for uterine fibroid
≠ 500-700 µm)
embolization
• Microspheres color-coded
• Just released in Europe
(november 2015)
Conclusion
Calibrated microspheres
Easy to handle
Easy injection of large microspheres through
microcatheterswithout clugging
Targeted embolization achievable
Conclusion
Be aware of mechanical differences between
products (trisacryl vs PVA vs PEG, …)
Extensive data available with Embosphere
Limited data at this point with Embozene and
Hydropearl
Future of particulate embolization: drug-eluting,
imaging detectable, resorbable, …