Cyanoacrylate is a device widely used in the medical field:
- Cardiac Surgery
- Vascular surgery
- Neurosurgery
- Otolaryngology surgery
- Thoracic surgery
- General surgery
- Gynecological surgery
There are several types of cyanoacrylate:
- Methyl 2-cyanoacrylate
- Ethyl-2-cyanoacrylate
- N-butyl cyanoacrylate
- 2-octyl cyanoacrylate
The length of the side chains of the cyanoacrylate molecule determines the speed of polymerization : longer chains determine slower reaction speed.
Polymerization is a CHEMICAL REACTION that leads to the formation of a chain polymer,
that is a molecule made up of equal parts that repeat in sequence starting from simpler molecules (Fig.1,
Fig.2).
The polymerization is triggered by the ions plasma.
Fig. 1: Cyanoacrylate chains.
Fig. 2: Polymerization reaction.
Cyanoacrylate application on CDV:
In contact with the N-butyl plasma solidifies due to a very rapid polymerization causing a strong inflammatory reaction of the endothelium.
Histologically cyanoacrylate determines an inflammatory reaction from foreign body with fibrotic segments inside the lumen of the vessel without involvement of the perivascular tissues (Fig.4,
Fig.5,
Fig.6,
Fig.7,
Fig.8)
Fig. 4: Intravenous reaction from a foreign body after ablation with cyanoacrylate.
Fig. 5: Intravenous reaction from a foreign body after ablation with cyanoacrylate.
Fig. 6: Doppler evaluation of intravenous reaction from a foreign body after ablation with cyanoacrylate.
Fig. 7: Elastosonography evaluation of intravenous foreign body reaction after cyanoacrylate ablation.
Fig. 8: Elastosonography evaluation of intravenous foreign body reaction after cyanoacrylate ablation.
Cyanoacrylate ablation is performed to treat CDV due to:
- Incompetent great saphena
- Incompetent small saphena
- Incompetent perforating veins
After careful haemodynamic study,
cyanoacrylate makes possible a point ablation of focal venous segments responsible for insufficiency: CHIVA-like mini-invasive conservative technique.
Cyanoacrylate non-thermal ablation procedure step by step:
- Evaluate all saphena vein with ultrasound.
- Identify and report tortuosity that may interfere with advancement of the catheter.
- Insert the introducer: percutaneous or small incision Seldinger technique.
- Advance the catheter (US control and light tip) to the Sapheno-Femoral junction.
- Retract the catheter (distal) up to at least 3cm from the confluence femoral,
extending it and pulling it with the gun.
- Map the saphena with a dermographic pen,
from the femoral confluence at access,
taking care to mark: 3cm distal to the confluence and successive 8-10cm,
up to the distal access,
in inverse proportion to the diameter of the vessel (> diameter,
<length).
- Start injection of cyanoacrylate: grip the gun and extend the catheter.
Move back the tip of the catheter up to 3cm from the confluence by pulling the gun.
- Compress the saphenous with the echo probe at the femoral confluence.
The occlusion of the confluence of the saphenous should be maintained for at least 10-12 "after the first glue injection,
ie for the whole procedure.
- Reassess the tip position to 3cm from the confluence before start the injection (bright tip and / or echo).
- Pull the trigger of the gun up to the end of the stroke.
Glue are injected every 8-10cm.
- Retract without stopping the gun / catheter until the first skin marker (8-10cm),
counting 3-4 sec.
- Apply a strong coat (eg the eco probe operator) with your free hand compression on the saphenous vein,
crushing it and squeezing it in the direction distal.
- Continue to compress throughout the injection,
following the tip.
- Repeat continuously from the confluence of the saphena to the foot for 3-4 minutes.
- Repeat the operation until the exit of the catheter from the vein.
At the end of treatment:
- Compress the access hole until hemostasis.
- Perform a check with US.
- Any persistence of small segments still pervaded but well occluded upstream and downstream not needs further treatment.
- Apply a compression bandage to the entry hole.
- DO NOT compress the limb with a compression bandage.
- Cutaneous redness and discomfort may occur in very superficial veins: this reaction lasts a few days with topical treatment (es.gel eparinoid e and inflammation).
The newest Cyanoacrylate non- thermal ablation vs Rf / Laser thermal ablation:
Advantages:
- NO compressive bandage of the limb can get up and leave independently
- Well tolerated by the patient
- Absence of tumescence
- Outpatient management
- Efficient and safe technique
Disadvantages and possible adverse reactions:
- High costs
- Cutaneous redness and discomfort can occur in very superficial veins: reaction from a foreign body,
lasting a few days may be useful topical treatment (es.gel eparinoid and anti-inflammatory).