Facial and body contouring with 1444 nm Nd:YAG laser‐assisted lipolysis: Clinical evidence

Abstract Background Body contouring is a significant area of dermatologic and plastic surgery. Surgical procedures, like surgical lipectomy, and less invasive procedures, such as various liposuction techniques, are the two main ways to reduce fat. Aim Our study showed that 1444 nm Nd:YAG laser‐assisted lipolysis used with appropriate and specific parameters effectively destroys adipose tissue avoiding these risks and determining a safe clinical application. Method A subcutaneous, 1444 nm Nd:YAG laser was used on 132 patients (range, 18–73 years; 109 women and 23 men with Fitzpatrick skin phototypes ranging between II and V) requiring body and face contouring. All patients were photographed for documentation. Digital clinical photography was taken under as near identical conditions as possible at baseline (pre‐treatment), and 16 weeks post‐treatment. The 5‐point Global Aesthetic Improvement Scale (GAIS) was recorded immediately after treatment and at their final assessment session (4 months). Adverse events were monitored. Results On the basis of the investigator‐evaluated GAIS scale, the total GAIS scores showed satisfactory results. Clinician assessment from the clinical photography showed good efficacy and visible aesthetic results for body and face areas. No serious or unexpected adverse side effects were recorded, and transient pain, oedema, erythema and slight induration resolved within the first week of treatment. Conclusions The 1444 nm Nd:YAG laser is a new tool for performing lipolysis, and this study reports its effectiveness and safety.

Laser lipolysis was also used by Prado et al. 4 to reduce abdominal fat.
Each laser selects a specific chromophore as its target with a different level of affinity. It is clear that the laser's photoacoustic and photothermal effects on fat and water result in lipolysis. 5,6 According to Anderson et al,7 some other wavelengths of laser have a greater affinity for fat than the 1064 nm laser. It has been hypothesized that laser lipolysis can be carried out more successfully with the 1444 nm wavelength since its affinity for fat is more than ten times greater than that of the 1064 nm wavelength.
Additionally, 14% of fat and about 60% of collagen are made up of water. 6 When compared to the 1064 nm laser, the 1444 nm laser's increased affinity with water was significantly greater than its increased affinity for fat 8 Consequently, dermal tightening and less bleeding are some of the positive effects of laser lipolysis.
Note that, 1444 nm laser lipolysis is known to be a relatively safe treatment with fewer associated risks and side effects than surgical liposuction for clinical use. 9--11 Furthermore, an article recently published 12 using the 1444 nm Nd:YAG laser in the management of lipoma was found to be a minimally invasive, scar-free, safe and effective procedure.
Notwithstanding, significant treatment-related issues, such as permanent scarring, developing large fibrotic areas in the subcutis that lead to irregularity of the overlying skin texture, formation of palpable or visible nodules in the skin, and other possible sequelae could persist during long-term follow-up in direct relation to the amount of laser energy used.
Our study showed that 1444 nm Nd:YAG laser-assisted lipolysis used with appropriate and specific parameters effectively destroys adipose tissue avoiding these risks and determining a safe clinical application. A cannula with a 600-m optical fibre was introduced through a 1 mm incision after making sure that the patient and the entire team had appropriate eye protection. The optical fiber can be equipped with a thermal sensor that monitors and maintains the average subdermal temperature below a defined value, and an embedded accelerometer to prevent overheating thanks to a delivery modulation. To make the fibre slightly longer than the cannula, it was threaded through the proximal end of the clamp. The fibre didn't extend further than 2-3 mm even beyond the cannula's end. The fibre tip had to be outside the cannula when the laser emission was turned on. The handpiece was taken out of the treatment area after the procedure. The

Assessments
All patients were photographed for documentation. Digital clinical photography was taken under as near identical conditions as possible at baseline (pre-treatment), and 16 weeks post-treatment.

Adverse effects
Adverse effects include bleeding, pain, infection, scarring, skin and fat tissue necrosis, itching, numbness, skin contour irregularities, skin discolouration purpura, asymmetry, surgical shock, pulmonary complications, aesthesia, skin loss, hair loss at the treatment area, seroma, allergic reaction, and anaesthesia-related complications, were monitored.

RESULTS
All patients completed the study. On the basis of the investigatorevaluated GAIS scale, the total GAIS scores showed satisfactory results: for body areas, most patients, 52%, experienced better than 3-score (good improvement) changes. Moreover, 36% of the patients experienced better than 4-score (excellent improvement) changes.  Figure 1).
In addition, Table 2 illustrates the GAIS score results for each face-treated area and the GAIS score results for each body-treated area (see Figure 2)  F I G U R E 2 Histogram representing the Global Aesthetic Improvement Scale (GAIS) score results for each body-treated area.

DISCUSSION
Scientific investigations have shown that near-infrared laser-assisted lipolysis is a fast, secure, and efficient method of removing extra body fat from a variety of locations. However, removing fat from the face has proven to be more challenging.
Histologic studies showed that 1444 nm Nd:YAG laser-assisted had an efficient lipolytic effect with less inflammation, lipolysis effectively destroys adipose tissue. 11 The usual method for performing laser lipolysis is to use a cannula with a laser fibre. By inserting the cannula into the treatment area and moving it back and forth, laser energy removes unwanted fat.
Dissolved fat can move into the extracellular space thanks to the transient pores that laser-assisted lipolysis causes in the cell membranes of adipocytes. The laser's short pulse, which is well below the fat's thermal coefficient of relaxation, prevents secondary thermal damage even though the laser energy is instantly converted to heat in that small volume of tissue. With the appropriate and consistent movement of the cannula or fibre, secondary conducted heat is reduced, creating a purely radiant heat effect and nonselective photothermolysis that helps prevent skin overheating and potential burn damage. This is crucial for laser-assisted facial contouring, as the fat layer and skin are much thinner than in other anatomical parts of the body.
Laser lipolysis offers several advantages: less bleeding, less pain and swelling, dermal tightening, no need for an incision and repair, minimal tissue damage, and early recovery compared to other liposuction methods. 5,[13][14] Our findings confirm these positive lipolytic effects of 1444 nm laser for several different body and face areas. According to photographic documentation and the GAIS scale, satisfactory aesthetic results were achieved following this kind of laser treatment modality.

STUDY LIMITATION
Study limitations are represented by the lack of ultrasounds and/or histological evaluation with a limited patient's sample. Our future goal will be to increase patient's numbers and to perform valid objective as F I G U R E 6 Lateral views of abdomen and culotte of a female patient before (A) and after (B) 1444 nm Nd:YAG laser lipolysis treatment (4 months follow-up). The aesthetic outcomes were good and noticeable.
well as subjective assessments for better analysis of laser treatment performance.

CONCLUSIONS
The 1444 nm Nd:YAG laser is a new tool for performing lipolysis, and this study reports its effectiveness and safety. The encouraging findings of this study demonstrate that it has significant advantages over other techniques due to its effective lipolytic properties.

CONFLICT OF INTEREST STATEMENT
I.F. is employed at El.En. Group. The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

FUNDING INFORMATION
This research received no external funding.

DATA AVAILABILITY STATEMENT
Data that support the study findings are available on request from the corresponding author.