Catheter Placement Into The Uterine Artery
A catheter reaches the uterine artery through the femoral artery.
- Femoral artery: Access site (most common approach)
- 4–5 Fr: Catheter size (guided microcatheter inside)
- Fluoroscopy: Guidance method (real-time X-ray imaging)
- Uterine artery: Target vessel (often catheterized bilaterally)
Femoral access and navigation
Interventional radiologist punctures the femoral artery under local anesthesia.
A guidewire steers the catheter past the aortic bifurcation into the pelvis.
Reaching the internal iliac artery
Catheter advances through the iliac artery toward its anterior branch.
Selective uterine artery catheterization
Microcatheter tip is placed just inside the uterine artery ostium.
Embolic Particles Injected Into The Uterine Artery
Tiny particles are injected to block blood flow feeding fibroids.
- PVA / microspheres: Particle material (calibrated, biocompatible)
- 500–900 µm: Particle size (typical range used)
- Pulsed, fluoroscopic: Injection method (controlled contrast pushes)
- Near-stasis flow: Injection endpoint (signals adequate embolization)
Choosing particle size
Larger particles block small arteries feeding the fibroid selectively.
Contrast-guided injection
Particles are pushed slowly while flow is watched on fluoroscopy.
Particles preferentially lodge in the fibroid's dense, low-resistance vessels.
Bilateral treatment
Both uterine arteries are typically embolized in one session.
Fibroid-Feeding Vessels Become Selectively Occluded
Particles clog fibroid arterioles while sparing normal myometrium.
- Preferential uptake: Fibroid flow (hypervascular tissue draws particles)
- Terminal arterioles: Occlusion level (not the main trunk)
- Collateral spared: Myometrium (dual blood supply protects it)
- Near-stasis: Procedure endpoint (confirms adequate occlusion)
Why fibroids are vulnerable
Fibroids rely on abnormal, low-resistance feeding arteries.
Sparing the myometrium
Normal muscle keeps flow through ovarian collateral vessels.
Myometrium receives blood from multiple redundant vascular sources.
Confirming occlusion
Angiography shows stagnant contrast in fibroid-feeding branches.
Fibroid Tissue Undergoes Ischemic Infarction
Without blood supply the fibroid begins shrinking over weeks.
- 40–60%: Volume reduction (typical at 6 months)
- 24–48 hours: Necrosis onset (after embolization)
- Coagulative necrosis: Tissue fate (no blood supply remains)
- 3–6 months: Symptom relief (gradual improvement reported)
Ischemic necrosis begins
Deprived tissue dies within one to two days.
Gradual volume loss
Fibroid shrinks steadily as dead tissue resorbs.
Most shrinkage occurs within the first three to six months.
Symptom improvement
Bleeding and bulk symptoms ease as fibroid shrinks.
Myometrium Retains Healthy Blood Flow
Normal uterine muscle stays perfused and undamaged throughout.
- >90%: Myometrial perfusion (via collateral circulation)
- Usually preserved: Ovarian reserve (rare ischemic complication)
- <3%: Amenorrhea risk (uncommon adverse outcome)
- 1–2 weeks: Recovery time (return to normal activity)
Redundant vascular supply
Myometrium draws flow from ovarian and vaginal arteries.
Fertility considerations
Most patients retain normal menstrual and ovarian function.
Uterine artery embolization preserves the uterus without surgery.
Long-term outcome
Fibroid remains shrunken while healthy tissue functions normally.