Non-thermal, non-tumescent based techniques include the use of technologies that avoid the use of heat to close the refluxing vein, and so avoids the necessity for repeated local anesthetic injections, and injections of large quantities of fluid into the skin and the discomfort associated with this.

There are two primary modalities one based on use of a biological proprietary formulation of a cyanoacrylate glue and the other uses a mechano-chemical technique with sclerosant injection during internal vein wall irritation with a spinning wire tip. The first technique called the VenasealTM technique uses a modified biologically inert cyanoacrylate glue to literally occlude together the vein walls using the glue that sets on contact with the warm blood inside the vein lumen. It is free of the need for tumescent injection and the need for postoperative compression therapy and the mobilization is immediate following treatment. It is very convenient with few side effects except occasional phlebitis in large tributaries that is usually self-resolving. It is not currently covered by insurance in the USA at time of writing but is FDA approved for use in the USA. The second technique is a sclerosant based technique, in which sclerosant is injected while a spinning wire tip scrapes the inside of the vein wall promoting sclerosant entry into the vein wall and vein wall destruction. This is known as mechanochemical vein ablation (ClariveinTM procedure). Both techniques are biologically equivalent for vein closure efficacy with the laser and radiofrequency techniques. Convenience, reduced complications, and easier tolerance and mobilization remain the great hope for these techniques which are currently available and FDA approved in the USA.