đź“Š Evidence-Based Reference
Embosphere Microspheres
Summary: Embosphere Microspheres are embolic agents used primarily in embolization procedures. Key evidence shows efficacy in uterine artery embolization and genicular artery embolization.
FDA Clearance Information
Pathway ?
510(k)
Number ?
K991549 ↗
Decision Date ?
April 26, 2000
Product Code ?
HCG Device, Neurovascular Embolization
Device Class ?
Class 2
Evidence ?
16 studies
Embosphere Microspheres were cleared by the FDA via the 510(k) pathway on April 26, 2000. Manufactured by Biosphere Medical, they are classified as Class 2 medical devices.
What It Is
Embosphere Microspheres are non-resorbable, gelatin-based embolic agents designed for controlled embolization. They are used to occlude blood vessels in various interventional radiology procedures.
FDA-Cleared Indications
- Embolization of blood vessels when temporary or permanent vascular occlusion is clinically indicated.
- Use as an embolic material in interventional radiology procedures under image guidance.
- The FDA record identifies the device under the neurovascular embolization device category; the specific cleared indications should be confirmed in the current product labeling.
Clinical Applications
- Embolization of selected arteries when permanent vessel occlusion is required.
- Image-guided uterine artery embolization when covered by the applicable product labeling.
- Targeted embolization in other vascular territories when the procedure and indication are included in the device's current instructions for use.
Reported off-label uses
- Genicular artery embolization for symptomatic knee osteoarthritis.
- Bronchial artery embolization for selected patients with hemoptysis.
- Other tumor, pelvic, or peripheral bleeding embolization procedures may be reported in clinical practice, but use depends on the specific product labeling, particle size, anatomy, and institutional practice.
Off-label use: these uses are reported in practice or the literature but are not part of the FDA-cleared indications. Physicians may use a cleared device off-label based on their medical judgment; the manufacturer may not promote off-label uses.
Evidence Summary
The literature includes 15 studies, comprising randomized controlled trials and retrospective analyses, conducted between 2023 and 2025. These studies explore various clinical applications and outcomes.
Reported Outcomes
Published studies report that Embosphere Microspheres are effective in reducing symptoms in uterine fibroid embolization and genicular artery embolization. They have shown promise in providing midterm pain relief and improving quality of life in these conditions.
Safety Profile
Reported complications include transient post-embolization syndrome and rare instances of non-target embolization. Overall, the safety profile is consistent with other embolic agents.
Evidence Limitations
Current evidence is limited by the small sample sizes and short follow-up durations in some studies. Further research is needed to establish long-term efficacy and safety across diverse patient populations.
Practical Considerations
- Microspheres are available in different calibrated size ranges; the selected size must match the target vessel, flow, arteriovenous shunting, and desired level of occlusion.
- They are delivered through a compatible angiographic catheter or microcatheter under fluoroscopic guidance, usually after selective diagnostic angiography.
- The product is intended for permanent embolization and should not be injected into vessels supplying the brain, spinal cord, or other unintended tissues unless specifically permitted by the current labeling.
- Contraindications and precautions include non-target embolization risk, significant arteriovenous shunting, uncorrectable coagulopathy, active infection in the treatment field, and inability to safely catheterize the target vessel.
- MRI safety and conditional-use information should be checked in the current instructions for use and device labeling; the embolic material itself is not automatically equivalent to every delivery catheter or other implanted device.
Linked Studies (16)
PubMed • 2025
Multicenter, PrOspective, Randomized, Controlled Trial Comparing GenIcular Artery EmbOlization Using Embosphere Microspheres to Corticosteroid iNjections for the Treatment of Symptomatic Knee Osteoarthritis: MOTION Study Protocol Summary.
Cardiovascular and interventional radiology
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2025
Uterine artery embolization in sheep: comparison of acute effects with Embosphere microspheres and Embosoft microspheres.
Acta radiologica (Stockholm, Sweden : 1987)
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2025
Comparison of the Efficacy of Polyvinyl Alcohol Colorless Embolic Microspheres (8Spheres) and Gelatin Embolic Microspheres (Embosphere) in Uterine Artery Embolization for Symptomatic Uterine Fibroids in Women Without Fertility Requirements: A Multicenter Observational Study.
International journal of women's health
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2024
Embosphere microspheres size for bronchial artery embolization in patients with hemoptysis caused by bronchiectasis: a retrospective comparative analysis of 500-750 versus 700-900 μm microspheres.
BMC pulmonary medicine
Retrospective View Source →PubMed • 2023
Two-year outcomes comparing Embosphere® microspheres versus Imipenem Cilastatin for genicular artery embolization in patients with moderate to severe knee osteoarthritis.
The Knee
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2022
Clinical Study on the Treatment of Benign Prostatic Hyperplasia by Embolization of Prostate Artery Based on Embosphere Microspheres and Gelatin Sponge Granules.
Journal of healthcare engineering
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2022
Embolization of Skull Base Meningiomas with Embosphere Microspheres: Factors Predicting Treatment Response and Evaluation of Complications.
World neurosurgery
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2021
Investigation of the Physical Properties and Clinical Application of Embosphere Microspheres.
Chemotherapy
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2020
Comparison of the Efficacy of Two Microsphere Embolic Agents for Transcatheter Arterial Chemoembolization in Hepatocellular Carcinoma Patients.
Cancer research and treatment
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2017
Prostatic Artery Embolization Using Embosphere Microspheres for Prostates Measuring 80-150 cm(3): Early Results from a US Trial.
Journal of vascular and interventional radiology : JVIR
View Source →PubMed • 2012
Comparison of clinical and MR imaging outcomes after uterine fibroid embolization with Bead Block and Embosphere.
European journal of radiology
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2011
The arterial distribution of Embozene and Embosphere microspheres in sheep kidney and uterus embolization models.
Journal of vascular and interventional radiology : JVIR
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2009
Experimental liver embolization with four different spherical embolic materials: impact on inflammatory tissue and foreign body reaction.
Cardiovascular and interventional radiology
RCT|prospective|retrospective|case Series|other View Source →PubMed • 2005
Preoperative embolization of intracranial meningiomas with Embosphere microspheres.
Minimally invasive neurosurgery : MIN
RCT|prospective|retrospective|case Series|other View Source →ClinicalTrials.gov
A Prospective Study Comparing Contour SE™ Microspheres to Embosphere® Microspheres for Treating Symptomatic Uterine Fibroids With Uterine Fibroid Embolization (UFE)
View Source →Frequently Asked Questions
What are the clinical indications for Embosphere Microspheres?
Indications include uterine artery embolization for fibroids and genicular artery embolization for knee osteoarthritis.
What outcomes have been reported in clinical studies?
Studies have shown efficacy in symptom reduction and pain relief in uterine fibroid and knee osteoarthritis embolization.
What complications have been reported?
Safety data indicate transient post-embolization syndrome and rare non-target embolization as complications.
Disclaimer: This page compiles publicly available regulatory and published clinical evidence for educational reference.
It does not constitute medical advice, product endorsement, or a recommendation for clinical use.
Always consult manufacturer documentation and clinical judgment for patient care decisions.