Reference · Dr Sin Yong · Singapore

Evidence Library

Published research on common aesthetic treatments, in plain summaries with links to each source.

In Brief

This library lists peer-reviewed studies and regulatory statements on common aesthetic treatments. It includes positive, mixed and negative findings. A study on one device or protocol does not prove results for another, and no study can predict your own result.

HIFU

Systematic review: Across 16 studies, pooled investigator scores showed improvement in 92% of patients at day 90, mostly mild or moderate, and adverse effects were uncommon at about 2%.
Contini M, et al. A Systematic Review of the Efficacy of Microfocused Ultrasound for Facial Skin Tightening. Int J Environ Res Public Health. 2023;20(2):1522. View source
Systematic review: Across 45 clinical trials and cohort studies, skin laxity improved by 18% to 30%, mainly in the lower face, neck and periorbital regions, with fewer than 5% of patients reporting transient erythema, swelling or mild discomfort.
Haykal D, et al. A Systematic Review of High-Intensity Focused Ultrasound in Skin Tightening and Body Contouring. Aesthet Surg J. 2025;45(7):690-698. View source

Ultherapy

Systematic review: Across 42 studies, 89% of patients were rated improved by investigators and 84% reported improvement, mean pain was 4.85 out of 10, and the authors noted that counting neutral responses as positive may overestimate efficacy.
Amiri M, et al. Microfocused Ultrasound With Visualization (MFU-V) Effectiveness and Safety: A Systematic Review and Meta-Analysis. Aesthet Surg J. 2025;45(3):NP86-NP94. View source
Narrative review: This manufacturer-affiliated review found common effects were mild and temporary (tenderness, redness, slight swelling), with rare bruising, welts and nerve effects, and rare surface thermal injury linked to improper technique.
Hitchcock TM, Dobke MK. Review of the safety profile for microfocused ultrasound with visualization. J Cosmet Dermatol. 2014;13(4):329-335. View source

Radiofrequency

Cohort: In 20 Korean women given a single treatment, dermatologist-rated jowl and nasolabial laxity improved at 12 and 24 weeks with no burns or scarring reported, but pores, fine wrinkles and skin tone did not change significantly.
Shin J, et al. Efficacy and Safety of Monopolar Radiofrequency for Tightening the Skin of Aged Faces. Cosmetics. 2024;11(3):71. View source

Thermage

Pilot study: In tissue studies of the ThermaCool TC device, collagen fibrils appeared to contract immediately after treatment and collagen type I mRNA expression increased, while light microscopy showed no observable changes at 3 or 8 weeks.
Zelickson BD, et al. Histological and Ultrastructural Evaluation of the Effects of a Radiofrequency-Based Nonablative Dermal Remodeling Device: A Pilot Study. Arch Dermatol. 2004;140(2):204-209. View source
Expert opinion: This opinion article states that patients can generally expect a 5% to 20% improvement, that results for any given group are unpredictable, and that detailed counselling is needed for realistic expectations.
Burns JA. Thermage: Monopolar Radiofrequency. Aesthet Surg J. 2005;25(6):638-642. View source

Fractional CO2 Laser for Acne Scars

Systematic review: Across seven studies, most patients showed roughly 30% to 70% improvement in scar appearance, with transient erythema, oedema and post-inflammatory hyperpigmentation as common adverse events, and the authors noted the need for long-term monitoring.
Ptaszek B, et al. The Use of a Fractional Laser in Acne Scar Treatment-A Systematic Review. Life (Basel). 2025;15(6):915. View source
Systematic review: In a network meta-analysis of nine randomised trials, all comparisons with laser monotherapy had confidence intervals crossing the null, confidence was rated low or very low, and the authors stated that a reliable treatment ranking does not currently exist.
Liu Y, et al. Minimally invasive interventions for atrophic acne scars: a PubMed/PMC-based systematic evidence review and exploratory network meta-analysis toward phenotype-guided interpretation. Front Surg. 2026;13:1943995. View source

Subcision

Narrative review: This review groups subcision tools into needles, cannulas, wires and blunt-blade instruments, and states that instrument choice depends on scar depth, personal preference and combined treatments.
Vempati A, et al. Subcision for Atrophic Acne Scarring: A Comprehensive Review of Surgical Instruments and Combinatorial Treatments. Clin Cosmet Investig Dermatol. 2023;16:125-134. View source
Cohort: In this uncontrolled study of 44 Vietnamese patients given three sessions, mean Goodman and Baron grade fell from 3.3 to 2.1 (P<0.001), with transient pain in 93%, oedema in 41% and erythema in 34%.
Nguyen LV, Lam TT. Treatment outcomes using subcision combined with platelet-rich plasma for atrophic acne scars: a study in Vietnamese patients. Skin Health Dis. 2026;6(4):477-484. View source
Cohort: In 45 patients with Fitzpatrick III to V skin, 95.6% improved by at least one Goodman and Baron grade after four combined sessions, and rolling and boxcar scars improved more than ice-pick scars.
Bhargava S, et al. Subcision and Microneedling as an Inexpensive and Safe Combination to Treat Atrophic Acne Scars in Dark Skin: A Prospective Study of 45 Patients at a Tertiary Care Center. J Clin Aesthet Dermatol. 2019;12(8):18-22. View source

TCA CROSS

RCT: In 30 patients randomised to four sessions of percutaneous collagen induction or 100% TCA CROSS, scar severity scores improved by a mean of 68.3% and 75.3% respectively, and the difference was not statistically significant (p=.47).
Leheta T, et al. Percutaneous collagen induction versus full-concentration trichloroacetic acid in the treatment of atrophic acne scars. Dermatol Surg. 2011;37(2):207-216. View source
Narrative review: Across 19 articles, 60% to 100% of acne scar patients showed more than 25% improvement on the quantile grading scale, with limitations including small samples and lack of control groups.
Chung HJ, et al. Chemical reconstruction of skin scars (CROSS) method for atrophic scars: A comprehensive review. J Cosmet Dermatol. 2021;20(1):18-27. View source
Narrative review: Across 34 publications and 937 patients, satisfaction or improvement rates were roughly 50% to 80%, higher TCA concentrations did not clearly improve efficacy but increased complication risk, and only one Fitzpatrick VI patient was included.
Stratman S, He H. The Use of Chemical Reconstruction of Skin Scars (CROSS) Method With Trichloroacetic Acid (TCA) for Atrophic Scars: A Comprehensive Review on Application Techniques, Adjunct Therapies, and Complications. J Clin Aesthet Dermatol. 2026;19(6):52-67. View source
Cohort: This prospective comparison concluded that improvement was best with 65% TCA, which also caused more adverse effects, especially acneiform eruption, while 50% glycolic acid was a safer alternative with acceptable results.
Roy G, et al. Study to compare the efficacy of 50% glycolic acid with 65% trichloroacetic acid in the treatment of atrophic acne scar by CROSS technique. J Cutan Aesthet Surg. 2024;17(3):198-204. View source

RF Microneedling

Systematic review: Across 16 studies and 481 patients, the authors concluded fractional radiofrequency microneedling is likely effective as a monotherapy and called for further randomised trials to establish treatment parameters.
Niaz G, et al. Fractional Radiofrequency Microneedling as a Monotherapy in Acne Scar Management: A Systematic Review of Current Evidence. Clin Cosmet Investig Dermatol. 2025;18:19-29. View source
Cohort: In 397 Thai patients with Fitzpatrick III to IV skin, mean 6-month improvement was 54.89% with fractional radiofrequency versus 47.53% with fractional laser (p=0.059), pain was higher with radiofrequency, and post-inflammatory hyperpigmentation was similar at about 5%.
Yan C, et al. Comparative Effectiveness and Safety of Fractional Laser and Fractional Radiofrequency for Atrophic Acne Scars: A Retrospective Propensity Score Analysis. Life (Basel). 2025;15(9):1379. View source
Case series: In this preliminary study, all 19 patients completed 2 to 6 monthly sessions, with mean pain of 1.5 out of 10 and no burns, scarring or pigment changes reported.
Elawar A, Dahan S. Non-insulated Fractional Microneedle Radiofrequency Treatment with Smooth Motor Insertion for Reduction of Depressed Acne Scars, Pore Size, and Skin Texture Improvement: A Preliminary Study. J Clin Aesthet Dermatol. 2018;11(8):41-44. View source

Acne Scar Types

Cohort: Classifying scars by the Jacob shape system (icepick, boxcar, rolling) proved subjective, with only 65% of scars matching across sessions, so the authors proposed size as the primary criterion (under 2 mm, 2 to 4 mm, over 4 mm).
Kang S, et al. New Atrophic Acne Scar Classification: Reliability of Assessments Based on Size, Shape, and Number. J Drugs Dermatol. 2016;15(6):693-702. View source
Narrative review: This review focuses on atrophic scars as the most common type and bases its algorithmic treatment approach on classifying scars as erythematous or atrophic.
Connolly D, et al. Acne Scarring—Pathogenesis, Evaluation, and Treatment Options. J Clin Aesthet Dermatol. 2017;10(9):12-23. View source
Narrative review: This review gives a step-by-step approach to evaluating atrophic acne scars with a treatment algorithm, and its full text uses a basic system of icepick, rolling and boxcar scars.
Fife D. Practical Evaluation and Management of Atrophic Acne Scars: Tips for the General Dermatologist. J Clin Aesthet Dermatol. 2011;4(8):50-57. View source

Pigmentation After Laser in Asian Skin

Narrative review: This review states that lasers require caution in darker skin because melanin acts as a competing chromophore, and recommends avoiding high energy settings, pulse stacking, short wavelengths and short treatment intervals.
Harnchoowong S, et al. Cosmetic Considerations in Dark-Skinned Patients. Clin Cosmet Investig Dermatol. 2024;17:259-277. View source
RCT: In this manufacturer-funded study of 59 patients with skin phototypes III to IV, the primary pigmentation score did not differ significantly between the two sunscreen sides at any visit after picosecond laser.
Puaratanaarunkon T, Asawanonda P. A Randomized, Double Blinded, Split-Face Study of the Efficacy of Using a Broad Spectrum Sunscreen with Anti-Inflammatory Agent to Reduce Post Inflammatory Hyperpigmentation After Picosecond Laser. Clin Cosmet Investig Dermatol. 2022;15:331-337. View source

Melasma

Systematic review: Across 42 articles, low-fluence Q-switched Nd:YAG was judged generally effective and safe, but mottled hypopigmentation occasionally persisted, aggressive use can cause hyperpigmentation especially in darker skin, and long-term follow-up data on recurrence are lacking.
Lee YS, et al. The Low-Fluence Q-Switched Nd:YAG Laser Treatment for Melasma: A Systematic Review. Medicina (Kaunas). 2022;58(7):936. View source
RCT: In 60 women with Fitzpatrick III to IV skin, picosecond Nd:YAG reduced MASI more than picosecond alexandrite (p=0.016) or 2% hydroquinone (p=0.018), alexandrite matched hydroquinone, and four patients (6.8%) had recurrence.
Liang S, et al. Comparison of the efficacy and safety of picosecond Nd:YAG laser (1,064 nm), picosecond alexandrite laser (755 nm) and 2% hydroquinone cream in the treatment of melasma: A randomized, controlled, assessor-blinded trial. Front Med (Lausanne). 2023;10:1132823. View source
Systematic review: Across 31 studies and 2,801 patients, Q-switched laser plus intense pulsed light had a higher efficacy rate than monotherapy (92.0% vs 77.4%) and lower recurrence (8.5% vs 17.8%), though recurrence data came from only four studies.
Zhang Y, et al. Efficacy and safety of Q-switched laser combined with intense pulsed light in treating melasma: a meta-analysis. Front Med (Lausanne). 2026;13:1749950. View source

Picosecond Laser

Cohort: In 12 Chinese patients with Fitzpatrick III or IV skin given one treatment, mean lesion clearance was 74.46%, and at eight weeks one patient had hyperpigmentation and one had hypopigmentation.
Huang Y, et al. Successful Treatment of Freckles Using a 730-nm Picosecond Laser: A Prospective Study. Clin Cosmet Investig Dermatol. 2024;17:3027-3032. View source
RCT: In 60 women treated in Beijing, picosecond Nd:YAG reduced MASI more than picosecond alexandrite or 2% hydroquinone, and the alexandrite laser matched hydroquinone (p=0.998).
Liang S, et al. Comparison of the efficacy and safety of picosecond Nd:YAG laser (1,064 nm), picosecond alexandrite laser (755 nm) and 2% hydroquinone cream in the treatment of melasma: A randomized, controlled, assessor-blinded trial. Front Med (Lausanne). 2023;10:1132823. View source
RCT: In 31 Asian patients with atrophic acne scars, the picosecond laser had comparable investigator-assessed efficacy to Er:YAG, with less pain and less post-inflammatory hyperpigmentation, though patient satisfaction was slightly higher on the Er:YAG side.
Dai R, et al. Comparison of 1064-nm Nd:YAG picosecond laser using fractional micro-lens array vs. ablative fractional 2940-nm Er:YAG laser for the treatment of atrophic acne scar in Asians: a 20-week prospective, randomized, split-face, controlled pilot study. Front Med (Lausanne). 2023;10:1248831. View source

Long-Pulsed 755 nm and 1064 nm Lasers

RCT: In 15 participants who completed the trial, hair reduction at 18 months was 73.6% to 84.3% with no significant difference among treatments, and combination therapy added no benefit but caused more hyperpigmentation and pain.
Davoudi SM, et al. Comparison of Long-Pulsed Alexandrite and Nd:YAG Lasers, Individually and in Combination, for Leg Hair Reduction: An Assessor-Blinded, Randomized Trial With 18 Months of Follow-up. Arch Dermatol. 2008;144(10):1323-1327. View source
Cohort: In 20 women with phototypes IV to VI, a 70% to 90% hair reduction persisted 12 months after three monthly long-pulsed 1064-nm treatments, with mild to moderate pain, rare vesiculation and transient pigment change.
Alster TS, et al. Long-Pulsed Nd:YAG Laser-Assisted Hair Removal in Pigmented Skin: A Clinical and Histological Evaluation. Arch Dermatol. 2001;137(7):885-889. View source
Narrative review: This review describes the 755 nm long-pulse alexandrite laser, absorbed by melanin and haemoglobin, as used for hair removal, vascular lesions and pigmented lesions, and states no specific efficacy results in its abstract.
Chen C, Ke Y. Applications of Long-Pulse Alexandrite Laser in Cosmetic Dermatology: A Review. Clin Cosmet Investig Dermatol. 2023;16:3349-3357. View source

Laser Hair Removal

Systematic review: In six studies of 423 women with PCOS, alexandrite laser improved hirsutism and outperformed intense pulsed light, but certainty of evidence was low and few studies assessed people with skin of colour.
Tan K, et al. Laser and Light-Based Therapies for Hirsutism Management in Women With Polycystic Ovarian Syndrome: A Systematic Review. JAMA Dermatol. 2024;160(7):746-757. View source
RCT: Both lasers were effective for leg hair removal at 18 months, with hair reduction of 73.6% to 84.3% and no significant difference among treatments.
Davoudi SM, et al. Comparison of Long-Pulsed Alexandrite and Nd:YAG Lasers, Individually and in Combination, for Leg Hair Reduction: An Assessor-Blinded, Randomized Trial With 18 Months of Follow-up. Arch Dermatol. 2008;144(10):1323-1327. View source
Narrative review: This review identifies appropriate patient selection, a suitable laser system and an experienced operator as the three main factors for success in facial laser hair reduction.
Goel A, Rai K. Methods to Overcome Poor Response and Challenges of Facial Laser Hair Reduction. J Clin Aesthet Dermatol. 2022;15(6):38-41. View source

Tattoo Removal

Cohort: In an intratattoo comparison of 16 black tattoos, picosecond-treated areas lightened significantly more than nanosecond-treated areas in 12 of 16 tattoos.
Ross EV, et al. Comparison of Responses of Tattoos to Picosecond and Nanosecond Q-Switched Neodymium:YAG Lasers. Arch Dermatol. 1998;134(2):167-171. View source
RCT: In 21 patients with 30 black tattoos, clearance did not differ between picosecond and nanosecond lasers (P=1.00), while pain was lower with the picosecond laser (3.8 vs 7.9 on a visual analogue scale).
Pinto F, et al. Neodymium-doped yttrium aluminium garnet (Nd:YAG) 1064-nm picosecond laser vs. Nd:YAG 1064-nm nanosecond laser in tattoo removal: a randomized controlled single-blind clinical trial. Br J Dermatol. 2017;176(2):457-464. View source

Rosacea and Vascular Laser

Systematic review: Across 10 included articles, clearance above 50% was 68.6% with pulsed dye laser and 71.4% with Nd:YAG (RR 0.94, 95% CI 0.75 to 1.17), with no significant differences between treatments.
Li Y, Wang R. Efficacy Comparison of Pulsed Dye Laser vs. Microsecond 1064-nm Neodymium:Yttrium-Aluminum-Garnet Laser in the Treatment of Rosacea: A Meta-Analysis. Front Med (Lausanne). 2022;8:798294. View source
Cohort: In this retrospective evaluation of 120 patients, total effective rates were 57.50% for pulsed dye laser, 45.00% for intense pulsed light and 67.50% for radiofrequency, with no statistically significant differences between groups.
Chen X, et al. Comparison of the Efficacy and Safety of Pulsed Dye Laser, Intense Pulsed Light and Radiofrequency Therapy in the Treatment of Erythematotelangiectatic Rosacea. Clin Cosmet Investig Dermatol. 2026;19:1-11 (article 562732). View source
Case series: In 66 patients, good to excellent improvement occurred in up to 50% of both erythematotelangiectatic and papulopustular groups, and hypopigmented atrophic scars occurred in two patients.
Say EM, et al. Treatment Outcomes of Long-Pulsed Nd: YAG Laser for Two Different Subtypes of Rosacea. J Clin Aesthet Dermatol. 2015;8(9):16-20. View source

Botulinum Toxin

Systematic review: In 11 placebo-controlled trials with 1,603 subjects, botulinum toxin type A improved facial wrinkles for about 4 to 6 months, no severe adverse effects were reported, and blepharoptosis after glabellar treatment occurred in 0% to 5.4%.
Gadhia K, Walmsley AD. Facial aesthetics: is botulinum toxin treatment effective and safe? A systematic review of randomised controlled trials. Br Dent J. 2009;207(5):E9. View source
Narrative review: In this review of five studies, with writing support funded by a manufacturer, the authors concluded that higher doses are feasible and may prolong response, with about 9 months' median duration at higher abobotulinumtoxinA or incobotulinumtoxinA doses.
Kaufman-Janette J, et al. Botulinum Toxin Type A for Glabellar Frown Lines: What Impact of Higher Doses on Outcomes?. Toxins (Basel). 2021;13(7):494. View source

Masseter Injections

RCT: In this manufacturer-supported trial of 376 adults, 51.2% on onabotulinumtoxinA 72 U versus 2.2% on placebo improved by at least 2 grades at day 90 (P<.0001), with mean lower-facial width reduction of 5.24 mm versus 0.04 mm.
Sun J, et al. OnabotulinumtoxinA Treatment for Masseter Muscle Prominence: 6-Month Safety and Efficacy Results, Including Patient-Reported Outcomes, From a Phase 3, Randomized, Placebo-Controlled, Multiregional Trial. Aesthet Surg J. 2026;46(5):486-494. View source
Narrative review: This manufacturer-supported narrative review covers injection technique, mechanism and clinical efficacy of botulinum toxin for benign masseter prominence in Asian populations, including clinical examples and one observed complication.
Wu Y, et al. Botulinum Toxin Type A for the Treatment of Masseter Muscle Prominence in Asian Populations. Aesthet Surg J Open Forum. 2023;5:ojad005. View source
RCT: In volunteers with masseter hypertrophy, the bulkiest height of the lower face decreased with botulinum toxin alone or with an oral appliance, and overall reduction was similar between groups at 24 weeks.
Park Y, et al. Combined Effects of Botulinum Toxin Injection and Oral Appliance Therapy on Lower Facial Contouring: A Randomized Controlled Trial. J Clin Med. 2022;11(14):4092. View source

Filler Safety

Consensus: The panel recommended prompt diagnosis and high-dose hyaluronidase of at least 200 U, with more if there is no improvement within 60 minutes, and reported that patients treated within 24 hours usually have the best outcomes in the authors' experience.
Cohen JL, et al. Treatment of Hyaluronic Acid Filler-Induced Impending Necrosis With Hyaluronidase: Consensus Recommendations. Aesthet Surg J. 2015;35(7):844-849. View source
Consensus: A multinational expert group stated that visual loss from hyaluronic acid filler is rare but catastrophic, and gave recommendations on consent, prevention and early bedside management.
Goodman GJ, et al. A Consensus on Minimizing the Risk of Hyaluronic Acid Embolic Visual Loss and Suggestions for Immediate Bedside Management. Aesthet Surg J. 2020;40(9):1009-1021. View source
Narrative review: This review separates vascular complications into external compression and filler entering vessels, identifies the nasolabial folds and nasal region as most susceptible, and covers management with hyaluronidase, vasodilators and hyperbaric oxygen.
Hong GW, et al. Adverse Effects Associated with Dermal Filler Treatments: Part II Vascular Complication. Diagnostics (Basel). 2024;14(14):1555. View source

Ultrasound-Guided Filler Work

Case series: In 39 patients, the ultrasound-guided targeted protocol used a mean of 122.5 IU of hyaluronidase versus 1519.4 IU for flooding, and the authors noted limitations in the study design.
Schelke LW, et al. Ultrasound-Guided Targeted vs Regional Flooding: A Comparative Study for Improving the Clinical Outcome in Soft Tissue Filler Vascular Adverse Event Management. Aesthet Surg J. 2023;43(1):86-96. View source
Case series: In a preliminary series of five women, the four treated promptly recovered fully with a mean hyaluronidase dose of 87 IU under ultrasound guidance, and the fifth, treated at 38 days, markedly improved.
Urso SU, et al. Use of Minimal Amounts of Hyaluronidase in the Ultrasound-Guided Treatment of Acute Vascular Occlusion by Hyaluronic Acid: A Preliminary Report. Aesthet Surg J Open Forum. 2024;6:ojae025. View source
Narrative review: This practice-based overview covers equipment choice, setup and two techniques for guiding injections, scanning before injecting or scanning while injecting, and reports no numerical outcomes.
Vasconcelos-Berg R, et al. Doppler Ultrasound-Guided Filler Injections: Useful Tips to Integrate Ultrasound in Daily Practice. Aesthet Surg J. 2023;43(7):773-783. View source

Calcium Hydroxylapatite

Systematic review: In this manufacturer-funded review of 12 studies, research generally reported increased collagen production, cell proliferation and angiogenesis, but most studies had methodological limitations and the authors called the evidence limited.
Amiri M, et al. Skin regeneration-related mechanisms of Calcium Hydroxylapatite (CaHA): a systematic review. Front Med (Lausanne). 2023;10:1195934. View source
Narrative review: This narrative review, with a manufacturer-employed co-author, attributes immediate volume restoration and increases in collagen, elastin and fibroblasts to calcium hydroxylapatite microspheres acting as a cell scaffold.
Aguilera SB, et al. The Role of Calcium Hydroxylapatite (Radiesse) as a Regenerative Aesthetic Treatment: A Narrative Review. Aesthet Surg J. 2023;43(10):1063-1090. View source
Consensus: Twelve experts, in manufacturer-supported work, agreed that cannulas should be used and disagreed on several area-specific points, concluding that the diversity of Asian patients calls for customised strategies.
Corduff N, et al. Pan-Asian Consensus on Calcium Hydroxyapatite for Skin Biostimulation, Contouring, and Combination Treatments. J Clin Aesthet Dermatol. 2021;14(8):E76-E85. View source
Case series: In paired skin samples from five women, type III collagen fibres were 34.42% at treated sites versus 1.76% at control sites two months after injection (p<0.01), in manufacturer-supported work.
Zerbinati N, Calligaro A. Calcium hydroxylapatite treatment of human skin: evidence of collagen turnover through picrosirius red staining and circularly polarized microscopy. Clin Cosmet Investig Dermatol. 2018;11:29-35. View source

Polynucleotides

Narrative review: This review describes varying degrees of efficacy and safety, with some studies showing gains in elasticity and hydration and others showing limited or no benefit, and concludes that more research is needed.
Lee KWA, et al. Polynucleotides in Aesthetic Medicine: A Review of Current Practices and Perceived Effectiveness. Int J Mol Sci. 2024;25(15):8224. View source
Narrative review: This review describes hyaluronic acid as superior for structural correction and polynucleotides as improving dermal quality, and states that heterogeneity in study design, formulation and outcomes limits firm conclusions.
Khan RS, Hafeez K. Hyaluronic Acid Fillers Versus Polynucleotides for Under-Eye Rejuvenation. J Clin Med. 2026;15(13):4971. View source
Expert opinion: This manufacturer-supported expert panel proposed protocols for four indications and stated that the evidence base is limited, calling for randomised trials and histological validation.
Rho NK, et al. Expert Perspectives: Evidence-Based Applications of Polynucleotides (PNs) in Aesthetic Medicine and Dermatology. Clin Cosmet Investig Dermatol. 2026;19:1-9 (article 557226). View source

Hybrid Hyaluronic Acid

Cohort: In this uncontrolled, distributor-supported study of 64 women, clinical and most objective measures improved and stayed significant at week 16, with minor temporary skin reactions in 23%.
Sparavigna A, Tenconi B. Efficacy and tolerance of an injectable medical device containing stable hybrid cooperative complexes of high- and low-molecular-weight hyaluronic acid: a monocentric 16 weeks open-label evaluation. Clin Cosmet Investig Dermatol. 2016;9:297-305. View source
Cohort: In this observational pilot of ten adults, pore size improved with a peak at day 120 and partial regression by day 180, and the authors called for larger controlled studies.
Koppert E, et al. Hybrid cooperative complex treatment is associated with reduced facial pore size in a pilot study. Sci Rep. 2026;16:26913. View source
Narrative review: This manufacturer-supported review of in vitro and in vivo literature describes hybrid cooperative complexes as made by a thermal process, in contrast to crosslinked hydrogels, and covers uses from facial and body rejuvenation onward.
Humzah D, et al. Intradermal Injection of Hybrid Complexes of High- and Low-Molecular-Weight Hyaluronan: Where Do We Stand and Where Are We Headed in Regenerative Medicine?. Int J Mol Sci. 2024;25(6):3216. View source

Thread Lifts

RCT: In 22 patients, using six rather than three threads per side made no significant difference to lifting outcomes or satisfaction, and early gains in volume and displacement faded by 60 days.
Germani M, et al. Is More Always Better? A Randomized Comparative Clinical Trial About the Impact of Polydioxanone Threads Quantity for Facial Lifting. Aesthet Surg J Open Forum. 2025;7:ojaf002. View source

Male Hair Loss

Systematic review: Across 23 studies, oral dutasteride 0.5 mg/d gave the greatest increase in total hair count at 24 weeks and oral finasteride 1 mg/d the greatest increase in terminal hair count at 48 weeks.
Gupta AK, et al. Relative Efficacy of Minoxidil and the 5-α Reductase Inhibitors in Androgenetic Alopecia Treatment of Male Patients: A Network Meta-analysis. JAMA Dermatol. 2022;158(3):266-274. View source
Systematic review: In seven trials with 396 men, the combination outperformed minoxidil alone for hair density (mean difference 9.22, p=0.04), and the authors called for larger confirmatory studies.
Li Y, et al. Comparing minoxidil-finasteride mixed solution with minoxidil solution alone for male androgenetic alopecia: a systematic review and meta-analysis of randomized controlled trials. Front Med (Lausanne). 2025;12:1632139. View source
Systematic review: In four studies, hair density did not differ significantly between oral and topical minoxidil (mean difference 0.95, 95% CI -24.98 to 26.87).
Fazal F, et al. Can oral minoxidil be the game changer in androgenetic alopecia? A comprehensive review and meta-analysis comparing topical and oral minoxidil for treating androgenetic alopecia. Skin Health Dis. 2025;5(2):95-101. View source

Female Hair Loss

Consensus: An expert task force concluded that treatment should start with 5% minoxidil, with 5α-reductase inhibitors or antiandrogens added for severe hair loss or hyperandrogenism.
Carmina E, et al. Female Pattern Hair Loss and Androgen Excess: A Report From the Multidisciplinary Androgen Excess and PCOS Committee. J Clin Endocrinol Metab. 2019;104(7):2875-2891. View source
RCT: In 120 women followed for 24 weeks, hair density increased most with minoxidil plus microneedling and least with minoxidil alone, and the spironolactone combination had the most adverse effects.
Liang X, et al. Efficacy and Safety of 5% Minoxidil Alone, Minoxidil Plus Oral Spironolactone, and Minoxidil Plus Microneedling on Female Pattern Hair Loss: A Prospective, Single-Center, Parallel-Group, Evaluator Blinded, Randomized Trial. Front Med (Lausanne). 2022;9:905140. View source
Systematic review: Across 42 studies, the authors concluded platelet-rich plasma showed efficacy for hair density in female pattern hair loss but that standardised protocols and large randomised trials are still required.
Zhou S, et al. Platelet-Rich Plasma in Female Androgenic Alopecia: A Comprehensive Systematic Review and Meta-Analysis. Front Pharmacol. 2021;12:642980. View source

Laser Therapy for Hair

Systematic review: In seven double-blinded trials, hair density improved compared with sham (standardised mean difference 1.27), and the authors called the therapy potentially effective and recommended long-term studies.
Lueangarun S, et al. A Systematic Review and Meta-analysis of Randomized Controlled Trials of United States Food and Drug Administration-Approved, Home-use, Low-Level Light/Laser Therapy Devices for Pattern Hair Loss: Device Design and Technology. J Clin Aesthet Dermatol. 2021;14(11):E64-E75. View source
Narrative review: Across 10 randomised trials, all sham-controlled studies showed significant increases in hair diameter or density, with only minor adverse effects, though the authors cautioned that some studies had industry ties.
Egger A, et al. Examining the Safety and Efficacy of Low-Level Laser Therapy for Male and Female Pattern Hair Loss: A Review of the Literature. Skin Appendage Disord. 2020;6(5):259-267. View source

PRP and Micrografts

Systematic review: In five randomised trials, adding platelet-rich plasma to minoxidil increased hair density at 5 to 6 months (mean difference 17.80), but certainty of evidence was low to very low.
Yao J, et al. The additive value of platelet-rich plasma to topical Minoxidil in the treatment of androgenetic alopecia: A systematic review and meta-analysis. PLoS One. 2024;19(8):e0308986. View source
Systematic review: In six trials, minoxidil performed better for terminal hair count and platelet-rich plasma for hair density, and the authors judged the efficacy of the two nearly comparable.
Abid A, et al. Comparison of the efficacy of platelet-rich plasma with topical minoxidil in treating patients with androgenetic alopecia: a systematic review of clinical trials. Skin Health Dis. 2025;5(5):311-318. View source
Narrative review: This manufacturer-funded review reports short-term improvements in hair density and thickness with autologous micrografting and calls for longer follow-up and better patient selection criteria.
Wang V, et al. A Decade of Autologous Micrografting Technology in Hair Restoration: A Review of Clinical Evidence and the Evolving Landscape of Regenerative Treatments. Cosmetics. 2025;12(6):254. View source

Exosomes

Narrative review: This review reports preclinical promise but states that clinical studies are lacking and that there are substantial safety concerns, naming possible infection, unwanted inflammatory response and promotion of malignancy.
Mahmoud RH, et al. Exosomes: A Comprehensive Review for the Practicing Dermatologist. J Clin Aesthet Dermatol. 2025;18(4):33-40. View source
Scoping review: Of 2,394 articles screened, 18 evaluated topical exosomes, human evidence was scarce, and commercial products gave little information on isolation, processing or shelf life.
Knauer G, et al. Clinical Evidence and Commercial Landscape of Topical Exosomes for Skin Rejuvenation: A Scoping Review. Aesthet Surg J. 2026;46(11):NP148-NP157. View source
Systematic review: All 11 studies showed improvement in at least one hair parameter with no serious adverse events noted, but only two were randomised, and the authors cited heterogeneity and small samples as limits.
Al Ameer MA, et al. Exosomes and Hair Regeneration: A Systematic Review of Clinical Evidence Across Alopecia Types and Exosome Sources. Clin Cosmet Investig Dermatol. 2025;18:2215-2227. View source
Narrative review: This review reports few high-quality clinical trials and adverse reactions with unapproved products marketed as exosome-based, and concludes that safe clinical use needs validation, standardisation and stronger regulation.
Contreras C, Ariza-Donado A. Extracellular Vesicles in Regenerative and Cosmetic Medicine: Safety, Clinical Effectiveness, Therapeutic Applications, and Regulatory Challenges. Int J Mol Sci. 2026;27(12):5541. View source

Radiofrequency for the Body

Cohort: In 44 patients in this manufacturer-supported study, ultrasound soft-tissue thickness fell by an average of 3.1 mm and abdominal circumference by 1.9 cm at 3 months after bipolar radiofrequency with electrical muscle stimulation.
Vranis NM, et al. Radiofrequency and Electrical Muscle Stimulation: A Synergistic Treatment That Achieves Lipolysis and Circumferential Waist Reduction in Noninvasive Body Contouring. Aesthet Surg J Open Forum. 2024;6:ojae042. View source
RCT: In 60 women allocated to ultrasound, radiofrequency or both, waist circumference fell after radiofrequency and combined treatment but not ultrasound, only radiofrequency had a lasting effect at 6 months, and no treatment changed lipid or insulin resistance markers.
Kiedrowicz M, et al. Early and Long-Term Effects of Abdominal Fat Reduction Using Ultrasound and Radiofrequency Treatments. Nutrients. 2022;14(17):3498. View source

Cryolipolysis

Systematic review: In 28 studies with 13,078 patients, pooled paradoxical adipose hyperplasia incidence was 0.22% (about 1 in 455), low-certainty evidence that the authors said appears higher than manufacturer reports.
Mah AE, et al. Incidence of Paradoxical Adipose Hyperplasia After Cryolipolysis: A Systematic Review and Meta-Analysis. Aesthet Surg J Open Forum. 2025;7:ojaf142. View source
Narrative review: This review reports fat reduction of up to 25% at the treatment site after one treatment, improvement in 86% of treated subjects and a 73% patient satisfaction rate.
Krueger N, et al. Cryolipolysis for noninvasive body contouring: clinical efficacy and patient satisfaction. Clin Cosmet Investig Dermatol. 2014;7:201-205. View source
Cohort: In this manufacturer-funded nonrandomised study of adults of Chinese descent, mean caliper-measured fat thickness fell by 6.5 mm in arms and 6.6 mm in inner thighs at 12 weeks, similar to a prior predominantly White cohort.
Rivers JK, et al. Cryolipolysis of the Arms and Inner Thighs Shows Similar Treatment Outcomes in Chinese Individuals Compared to White Individuals Treated in a Prior Study: The XinCOOL Study. Aesthet Surg J Open Forum. 2023;5:ojad103. View source
Cohort: In 2,114 patients at 8 Canadian centres, site-level incidence ranged from 0.05% to 0.39%, above the manufacturer's quoted 0.025%, and fell by over 75% after newer units were introduced.
Nikolis A, Enright KM. A Multicenter Evaluation of Paradoxical Adipose Hyperplasia Following Cryolipolysis for Fat Reduction and Body Contouring: A Review of 8658 Cycles in 2114 Patients. Aesthet Surg J. 2021;41(8):932-941. View source

Vaginal Laser

RCT: In 85 women randomised to fractional CO2 laser or sham, laser did not significantly improve vaginal symptoms after 12 months compared with sham.
Li FG, et al. Effect of Fractional Carbon Dioxide Laser vs Sham Treatment on Symptom Severity in Women With Postmenopausal Vaginal Symptoms: A Randomized Clinical Trial. JAMA. 2021;326(14):1381-1389. View source
Systematic review: In six randomised trials with 270 women, CO2 laser was associated with similar improvement in genitourinary symptoms as vaginal estrogen, with no significant differences on the main measures.
Jang YC, et al. Comparison of Severity of Genitourinary Syndrome of Menopause Symptoms After Carbon Dioxide Laser vs Vaginal Estrogen Therapy: A Systematic Review and Meta-analysis. JAMA Netw Open. 2022;5(9):e2232563. View source

Vaginal Radiofrequency

RCT: In this subanalysis of the sham-controlled VIVEVE I trial, with authors tied to the manufacturer, 108 premenopausal women had greater 6-month improvement with active treatment in arousal, lubrication and orgasm scores.
Krychman M, et al. Effect of Single-Session, Cryogen-Cooled Monopolar Radiofrequency Therapy on Sexual Function in Women with Vaginal Laxity: The VIVEVE I Trial. J Womens Health (Larchmt). 2018;27(3):297-304. View source
RCT: In 76 women, vaginal laxity improved more with active treatment than sham at 4, 6 and 12 months, but Female Sexual Function Index improvement was not significantly greater than sham at all visits.
Nappi RE, et al. Efficacy and safety of a device that combines multipolar radiofrequency with pulsed electromagnetic field for the treatment of vulvovaginal atrophy: a randomized, sham-controlled trial. J Sex Med. 2024;21(3):203-210. View source

Regulatory Positions on Vaginal Devices

Guidance: The FDA stated it has not evaluated these devices for vaginal rejuvenation uses, reported cases of vaginal burns, scarring, painful intercourse and chronic pain, and sent notices to seven manufacturers.
US Food and Drug Administration. Statement from FDA Commissioner Scott Gottlieb, M.D., on efforts to safeguard women's health from deceptive health claims and significant risks related to devices marketed for use in medical procedures for "vaginal rejuvenation". FDA statement. 2018. View source
Guidance: The societies recommended against using laser and radiofrequency for vulvovaginal atrophy and said these devices should not be used for lichen sclerosus, vulvodynia, urinary incontinence or rejuvenation outside properly designed clinical trials.
International Society for the Study of Vulvovaginal Disease, International Continence Society. ISSVD/ICS comments on the FDA communication on the use of energy-based devices to perform vaginal 'rejuvenation' or vaginal cosmetic procedures. ISSVD/ICS position statement. 2018. View source
Guidance: ACOG stated that laser therapy is neither FDA-approved nor FDA-cleared for symptoms related to menopause, that the evidence is mostly small observational studies, and that more research is needed before recommending it.
American College of Obstetricians and Gynecologists. Treatment of Urogenital Symptoms in Individuals With a History of Estrogen-dependent Breast Cancer: Clinical Consensus. ACOG Clinical Consensus No. 2. 2021. View source

Sun Protection

Cohort: In 14 elderly Japanese people followed for 18 months without a control group, changes in spots and skin tone uniformity correlated with the amount of sunscreen used, and skin hydration was the only measure that changed significantly.
Mizuno M, et al. The effects of continuous application of sunscreen on photoaged skin in Japanese elderly people - the relationship with the usage. Clin Cosmet Investig Dermatol. 2016;9:95-105. View source
Narrative review: This manufacturer-linked review states that skin of colour still faces photoageing and pigmentary disorders from UV exposure, and suggests broad-spectrum high-SPF sunscreens that also cover UVA1 and visible light.
Krutmann J, et al. Photoprotection for people with skin of colour: needs and strategies. Br J Dermatol. 2023;188(2):168-175. View source
Narrative review: This review reports that broad-spectrum sunscreen started early supports healing and lowers inflammation after laser procedures, and that patients often know to protect their skin but do not consistently follow through.
Lee KWA, et al. Importance of Using Sunscreen After Light or Laser Facial Treatment: A Literature Review. Life (Basel). 2025;15(9):1484. View source

Skin Boosters

Systematic review: This review reports improved hydration, firmness, texture and elasticity across hyaluronic acid formulations and calls the evidence for hyaluronic acid alone promising, but says large randomised trials are needed.
Ghatge AS, Ghatge SB. The Effectiveness of Injectable Hyaluronic Acid in the Improvement of the Facial Skin Quality: A Systematic Review. Clin Cosmet Investig Dermatol. 2023;16:891-899. View source
RCT: In 448 adults at five Chinese centres, intradermal non-cross-linked hyaluronic acid gave greater hydration than no treatment at all post-treatment time points (P<0.001), with no serious adverse events.
Cheng H, et al. A Prospective, Multicenter, Randomized, Assessor-Blinded Study Assessing the Efficacy and Safety of Injectable Non-Cross-Linked Hyaluronic Acid for Improving Facial Skin Rejuvenation. Clin Cosmet Investig Dermatol. 2026;19:1-10 (article 590699). View source
RCT: In 28 per-protocol subjects, in a study with manufacturer-affiliated authors, crow's feet wrinkle depth changed by -10% with the gel versus +7% with saline 10 days after the last session.
Duteil L, et al. The Effects of a Non-crossed-linked Hyaluronic Acid Gel on the Aging Signs of the Face versus Normal Saline: A Randomized, Double-blind, Placebo-controlled, Split-faced Study. J Clin Aesthet Dermatol. 2023;16(2):29-36. View source
RCT: In this manufacturer-funded randomised split-face study of women with mild-to-moderate photoaging, the higher-dose side showed superior and longer-lasting results than the lower-dose side.
Wang S, et al. Dose-Dependent Effects of Cross-Linked Hyaluronic Acid Through Intradermal Injection on Female Facial Photoaging: A Prospective Study. Aesthet Surg J Open Forum. 2025;7:ojaf046. View source

General information only. Last updated 3 November 2026.