Preoperative embolization of bone lesions

Preoperative embolization of bone tumours is a minimally invasive procedure performed by interventional radiologists to reduce the blood supply to a bone tumour before surgical removal. This procedure aims to minimise blood loss during surgery, making the operation safer and more manageable for both the surgeon and the patient. 

Indications

Preoperative embolization is typically indicated for:

1. Hypervascular Bone Tumours: These are tumours with a rich blood supply, such as osteosarcomas, giant cell tumours, and metastatic lesions from cancers like renal cell carcinoma.
2. Tumours in Critical Locations: Where excessive bleeding could complicate surgery, such as in the spine or pelvis.
3. Large Tumours: To help reduce the size and vascularity of the tumor, making surgical resection easier.

Procedure

1. Pre-procedure Planning:
   • Imaging Studies: Prior to embolization, detailed imaging studies such as MRI, CT, or angiography are performed to map the blood supply to the tumour.
   • Patient Preparation: The patient is typically given local anaesthesia, sometimes combined with sedation or general anaesthesia, depending on the tumour’s location and patient condition.
2. Catheter Insertion:
   • A small incision is made, usually in the groin, to access a major artery.
   • Using fluoroscopic guidance, a catheter is navigated through the arterial system to the arteries supplying the bone tumour.
3. Embolic Agent Injection:
   • Once the catheter is correctly positioned, embolic agents (materials that block blood flow) are injected. These agents can be particles, coils, glue, or liquid embolic agents.
   • The choice of embolic agent depends on factors like the size and type of the tumour, and the desired duration of occlusion.
4. Post-embolization Imaging:
   • Follow-up angiography is often performed immediately after embolization to confirm the reduction of blood flow to the tumor.
   • Additional imaging may be done in the days leading up to surgery to ensure continued occlusion.

Benefits

• Reduced Blood Loss: By significantly reducing the tumour’s blood supply, the procedure minimises intraoperative bleeding.
• Improved Surgical Field: Less bleeding provides a clearer surgical field, which can facilitate complete tumour removal.
• Lower Risk of Complications: With less intraoperative blood loss, the risk of complications such as transfusion reactions or hypotension decreases.

Risks and Considerations

• Procedure-related Complications: Although rare, complications can include infection, damage to surrounding tissues, or unintended embolization of non-target areas.
• Post-embolization Syndrome: Patients might experience pain, fever, or nausea after the procedure, typically managed with medication.
• Incomplete Embolization: Sometimes, it may not be possible to fully embolize the tumour, which can affect surgical outcomes.

Conclusion

Preoperative embolization of bone tumours is a valuable technique to enhance the safety and efficacy of surgical tumour resection. It requires careful planning and skilled execution by an interventional radiologist to maximise its benefits and minimise risks.