The Translation of Knowledge about Gold RF Microneedles

The advent of gold microneedles is actually based on the proven effectiveness of microneedles (roller needles), and when combined with radiofrequency (RF) energy, it can achieve even better results. Gold microneedles were first developed and launched in the United States in 2009, and the first relevant academic paper on them was published at that time.
What is a Gold Microneedle?
The scientific name of gold microneedles is radiofrequency microneedles, and a more precise term is “fractional radiofrequency microneedles”.
It is also one of the representative devices of the fractional mode. Sufficient spacing is maintained between the radiofrequency microneedles, leaving undamaged normal skin around the microneedles for repair. This ensures that while therapeutic effects are achieved, the damaged skin is repaired; otherwise, excessive damage would inevitably lead to scarring.
It is a minimally invasive treatment method that creates tiny punctures in the skin and delivers thermal energy generated by radiofrequency to the dermis (superficial, middle, and deep layers).
Internationally, photoelectric devices are categorized into invasive (in other words, traumatic) and non-invasive (non-traumatic) types.
Obviously, gold microneedles fall into the category of invasive traumatic devices, but with relatively minor trauma, so they are classified as minimally invasive devices.
Compared with ablative fractional lasers and non-ablative fractional lasers, which also adopt the fractional mode, the degree of damage caused by gold microneedles is proportional to their therapeutic effect.
That is to say, the effect of gold microneedles in stimulating collagen regeneration is weaker than that of ablative fractional lasers but stronger than that of non-ablative fractional lasers.
The same applies to skin damage: the adverse reactions caused by the trauma of gold microneedles are far more numerous and severe than those of non-ablative fractional lasers.
Core Parameters of Gold Microneedles
① Insulated or non-insulated② Monopolar or bipolar radiofrequency③ Length, quantity, and thickness of microneedles④ Frequency: Usually 1-2 MHz⑤ Pulse width: There is a significant variation in pulse width among different devices, typically ranging from several tens of milliseconds (ms) to hundreds of milliseconds (ms)⑥ Power: There is a large difference in power between different devices, which will be discussed later when specific devices are introduced.
Dual-Action Mechanism of Gold Microneedles
Gold microneedles are mainly used for skin rejuvenation and to improve issues caused by collagen problems, such as enlarged pores, wrinkles, and acne scars.
All gold microneedle devices promote the regeneration, remodeling of dermal collagen, and neogenesis of elastic fibers through the “damage-and-repair” mechanism.
Since gold microneedles are invasive, they achieve the above-mentioned effects through the dual action of the mechanical effect of the microneedles and the thermal effect of radiofrequency.
The radiofrequency current generates a thermal effect, that is, the heat produced in the tissue reaches the level of thermal denaturation to induce collagen regeneration.
Its mechanism of action is the same as that of other radiofrequency devices, such as Thermage, which all generate heat through the resistance of tissues when electric current passes through them.
The therapeutic effect is achieved by forming microthermal damage zones (MTZs) in the skin.
Summary
Gold microneedles were developed and launched in the United States in 2009.
Gold microneedle therapy is a minimally invasive and invasive treatment method.
There is a significant difference in the effects between insulated microneedles and non-insulated microneedles.
Gold microneedles exert their therapeutic effects through the dual action of the mechanical effect of the microneedles and the thermal effect of radiofrequency.
Gold microneedles act on the dermal layer. Non-insulated microneedles also have a certain effect on the epidermal layer, but this effect on the epidermis is mainly side effects, which can easily damage the epidermis and induce pigmentation.
The length and pulse width of the gold microneedles, as well as the type of radiofrequency (monopolar or bipolar), determine the size and depth of the thermal damage zones.
Factors affecting the thermal damage zones of gold microneedles include frequency. Higher energy (related to microneedle length) will cause greater damage. If the damage zone is too large, there will not be enough normal skin around to support repair, leading to severe adverse reactions.
Since gold microneedle therapy is invasive, after the treatment, some topical products can be applied and can be easily absorbed into the dermis. In contrast, non-ablative fractional lasers have a poor effect in promoting transdermal absorption, which is far inferior to the direct puncture channels created by gold microneedles.