靜脈曲張和 Spider 靜脈的硬化療法：技術、療效與病患選擇

Sclerotherapy remains one of the most established and versatile treatments for varicose and spider veins, offering an effective minimally invasive option with over a century of clinical use. This procedure involves injecting a specialized solution directly into affected veins, causing controlled damage that ultimately leads to their closure and reabsorption. This comprehensive guide explores modern sclerotherapy techniques, evidence-based outcomes, patient selection criteria, and practical considerations for optimal results.

Mechanism of Action and Sclerosing Agents

Sclerotherapy works through a process of controlled endothelial damage and subsequent fibrosis:

作用機制

Endothelial damage: The sclerosant directly damages the vein’s inner lining
炎症反應: Vessel wall inflammation is triggered
Fibroblast activation: Leads to collagen deposition
Fibrotic occlusion: The vein transforms into a fibrous cord
Reabsorption: Gradual resorption of the treated vein over weeks to months

Common Sclerosing Agents

Several sclerosing agents are available, each with distinct properties and applications:

Detergent Sclerosants

Sodium tetradecyl sulfate (STS):
Concentrations: 0.1-3%
Mechanism: Protein denaturation and endothelial damage
Applications: Effective for vessels of various sizes
FDA-approved for varicose veins
Polidocanol (POL):
Concentrations: 0.25-5%
Mechanism: Non-ionic surfactant with anesthetic properties
Applications: Associated with less pain and hyperpigmentation
FDA-approved for varicose veins

Osmotic Agents

Hypertonic saline:
Concentrations: 23.4-30%
Mechanism: Osmotic cellular dehydration
Applications: Primarily for smaller vessels
Limitations: More painful, higher risk of tissue necrosis

Chemical Irritants

Glycerin:
Formulation: Often combined with lidocaine and epinephrine
Mechanism: Mild sclerosant causing endothelial irritation
Applications: Ideal for fine telangiectasias, especially facial vessels
Advantages: Lower incidence of hyperpigmentation

Newer Agents

Sodium morrhuate:
Derived from cod liver oil
Applications: Alternative for patients with detergent allergies
Polidocanol endovenous microfoam (PEM):
Proprietary microfoam formulation
FDA-approved specifically for great saphenous vein incompetence

Modern Sclerotherapy Techniques

Contemporary sclerotherapy encompasses several specialized techniques:

Liquid Sclerotherapy

The traditional approach using liquid sclerosants:
– Concentration selection: Tailored to vessel size (lower for smaller vessels)
– Injection technique: Direct puncture with 30-32G needles for telangiectasias, 25-27G for larger vessels
– Volume limitations: Typically 0.1-0.5ml per injection site for telangiectasias, up to 1ml for reticular veins
– Session spacing: Usually 4-6 weeks between treatments

Research evidence: Multiple studies demonstrate 50-80% clearance rates for telangiectasias with liquid sclerotherapy, with patient satisfaction rates of 70-90%.

Foam Sclerotherapy

Mixing sclerosant with air or physiological gases creates microfoam:
– Preparation methods:
– Tessari technique (two syringes and three-way stopcock)
– DSS method (double syringe system)
– Proprietary systems (e.g., Varithena®)
– 優勢:
– Increased surface area contact with endothelium
– Displacement of blood allowing better sclerosant contact
– Visibility under ultrasound guidance
– Effective treatment of larger vessels with lower sclerosant concentrations
– Foam properties: Optimal bubble size 100-500μm; stability 2-3 minutes

Research evidence: A meta-analysis of 69 studies found that foam sclerotherapy achieved 81.4% occlusion rates for great saphenous veins compared to 64.4% for liquid sclerotherapy at one-year follow-up.

Ultrasound-Guided Sclerotherapy (UGS)

Utilizes real-time ultrasound visualization:
– 應用: Treatment of deeper, non-visible veins including saphenous trunks
– 技術: Precise needle placement and sclerosant delivery under direct visualization
– Monitoring: Real-time confirmation of vein emptying and sclerosant distribution
– Safety advantages: Reduced risk of inadvertent arterial injection or deep vein thrombosis

Research evidence: Randomized controlled trials show 5-year success rates of 72-84% for ultrasound-guided foam sclerotherapy of the great saphenous vein, though slightly lower than thermal ablation techniques.

Microsclerotherapy

Specialized technique for very small vessels:
– Equipment: Magnification systems (2.5-5x) and specialized lighting
– Needle size: Ultra-fine 32-33G needles
– Sclerosant selection: Typically glycerin or very dilute POL/STS
– 應用: Facial telangiectasias, matting, and residual vessels after other treatments

Clinical Efficacy and Outcomes

Extensive research documents sclerotherapy effectiveness across vessel types:

Telangiectasias and Reticular Veins

Clearance rates: 70-90% improvement with 1-3 sessions
Patient satisfaction: 80-95% report satisfaction with cosmetic outcomes
復發: 10-20% develop new vessels within 1-2 years
Comparative efficacy: Superior to laser therapy for vessels >1mm diameter

Small Varicose Veins

Technical success: 80-90% occlusion rates for vessels 3-6mm
Symptom improvement: 85% report significant symptom reduction
Sessions required: Typically 1-3 treatments
Durability: 70-80% remain closed at 3-year follow-up

Great and Small Saphenous Veins

Occlusion rates: 60-85% at 1 year with foam sclerotherapy
Comparative efficacy: Slightly lower durability than thermal ablation but similar symptom improvement
成本效益: More economical than surgical or endovenous thermal options
Retreatment rates: 15-30% require additional treatment within 5 years

Patient Selection and Contraindications

Proper patient selection is crucial for optimal outcomes:

理想的候選人

Telangiectasias and reticular veins (0.1-3mm diameter)
Small to medium varicose veins (3-6mm)
Residual or recurrent veins after other treatments
Patients seeking minimally invasive options
Tortuous veins not amenable to catheter-based treatments

相對禁忌症

Severe arterial insufficiency (ABI <0.7)
Significant leg edema without treatment
Local infection in treatment area
Known allergy to sclerosant
Limited mobility (affects post-procedure ambulation)

絕對禁忌症

Acute deep vein thrombosis or pulmonary embolism
Severe hypercoagulable state
Pregnancy and immediate postpartum period
Uncontrolled systemic illness
Patent foramen ovale (for foam sclerotherapy)

Procedural Considerations and Technique Refinements

Several technical factors influence outcomes:

Pre-procedure Assessment

Comprehensive venous mapping with duplex ultrasound
Documentation of reflux patterns and perforator status
Identification of saphenofemoral/saphenopopliteal incompetence
Photography for baseline comparison

Procedural Technique Refinements

Empty vein technique: Elevation, exsanguination, or compression
Injection pressure: Gentle, controlled pressure avoiding excessive force
Post-injection compression: Immediate compression after injection
Treatment sequencing: Proximal to distal approach for connected vessels
Volume limitations: Maximum 10ml of foam or 20ml of liquid sclerosant per session

Post-procedure Protocol

Compression therapy:
Duration: 1-3 weeks depending on vessel size
Pressure: 20-30 mmHg for most applications
Options: Stockings, bandages, or combination approaches
Ambulation: Immediate walking for 30-60 minutes post-procedure
Follow-up: Assessment at 2-4 weeks to evaluate results and need for additional treatment

Managing Complications

While generally safe, sclerotherapy can produce several complications:

常見副作用

Hyperpigmentation: Occurs in 10-30% of cases, usually resolves within 6-12 months
Matting: Development of fine telangiectatic networks in 5-15% of patients
Trapped blood: Occurs in 5-10% of treatments, may require microthrombectomy
Pain and ecchymosis: Typically mild and self-limiting

Less Common Complications

Allergic reactions: <1% incidence, ranging from mild urticaria to anaphylaxis
Superficial thrombophlebitis: 1-5% incidence, managed with NSAIDs and compression
Skin necrosis: <0.1% risk, related to extravasation or arterial injection
Visual disturbances: Rare with foam sclerotherapy, typically transient
Deep vein thrombosis: <0.6% risk, higher with foam treatment of saphenous trunks

Prevention and Management Strategies

Hyperpigmentation: Proper compression, avoiding extravasation, treating trapped blood
Matting: Conservative sclerosant concentrations, treating underlying reflux
Skin necrosis: Aspiration before injection, low-volume injections, immediate dilution if extravasation occurs
Thromboembolic events: Volume limitations, proper technique, post-procedure ambulation

醫療免責聲明

重要通知: This information is provided for educational purposes only and does not constitute medical advice. Sclerotherapy should only be performed by qualified healthcare professionals with appropriate training in venous procedures. The selection of sclerosing agents, techniques, and post-procedure care should be individualized based on patient characteristics, vessel anatomy, and physician expertise. All procedures carry potential risks and benefits that should be thoroughly discussed with your healthcare provider. This article is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition or treatment options.

總結

Sclerotherapy remains a cornerstone treatment for varicose and spider veins, offering an effective, minimally invasive option with excellent safety profile when properly performed. Modern advances in sclerosing agents, foam preparation techniques, and ultrasound guidance have expanded its applications and improved outcomes. While newer endovenous techniques have emerged for larger varicose veins, sclerotherapy continues to excel for small to medium vessels and as a complementary procedure following other interventions. With proper patient selection, technique refinement, and post-procedure care, sclerotherapy provides highly satisfactory cosmetic and symptomatic improvement for millions of patients worldwide.