Microfocused Ultrasound in Regenerative Aesthetics: A Narrative Review on Mechanisms of Action and Clinical Outcomes

Abstract

Background: Microfocused ultrasound with visualization (MFU-V) is widely used in aesthetic medicine for skin tightening and rejuvenation. However, its role in regenerative aesthetics and its precise mechanism of action are not fully understood.

Objective: This narrative review aims to contextualize and articulate the mechanism of action of MFU-V, evaluate its role in regenerative aesthetics, and assess its effectiveness based on existing clinical, histological, and skin-mechanical studies.

Methods: A comprehensive literature search was performed to collect and analyze studies on MFU's biological mechanisms, clinical outcomes, and impact on extracellular matrix (ECM) regeneration. The review integrates findings from clinical trials, histological analyses, and biomechanical assessments to provide a cohesive understanding of MFU-V's role in aesthetic medicine.

Results: MFU-V emits focused ultrasound energy that penetrates multiple skin layers and the superficial musculoaponeurotic system, creating localized thermal coagulation points. These points initiate biological responses that recruit fibroblasts and stimulate the production of new collagen and elastin fibers. Enhanced ECM protein synthesis leads to significant improvements in skin biomechanics and quality, reducing skin laxity and enhancing appearance. Clinical studies support these findings, showing improvements in skin firmness and texture following MFU-V treatment.

Conclusion: Through analyzing the underlying biological mechanisms and the observable clinical outcomes, this narrative review sets the stage for a comprehensive understanding of the mechanism of action and role of MFU-V in regenerative aesthetics.

Keywords: MFU‐V; Ultherapy; energy‐based devices; microfocused ultrasound with visualization; regenerative aesthetics.

FIGURE 1

MFU‐V transducers targeting various skin layers (SMAS, reticular/papillary dermis) at specific depths (4.5 mm, 3.0 mm, 1.5 mm), demonstrating precise depth‐controlled thermal coagulation. DS, DeepSee.

FIGURE 2

MFU‐V's mechanism of action for skin regeneration. (A) Three phases: Inflammation (TCP triggers immune response), Proliferation (fibroblasts produce new collagen/elastin), and Remodeling (collagen/elastin mature, restructuring skin). (B) Conceptual timeline and illustrative relative intensity of biological processes over 100 days. The y‐axis represents qualitative intensity.

FIGURE 3

(A) Hematoxylin & Eosin (H&E) staining shows the inverted cone appearance of thermal coagulation points (TCPs) 14 days post‐treatment with an R&D transducer using 0.25 J at a 1 mm depth with 10 MHz. (B) Safranin‐Hematoxylin–Eosin (SHE) staining reveals collagen degradation (darker arrowheads) and early fibroplasia (arrows) 14 days after treatment with ~0.8 J at a 3.0 mm depth. (C) Masson's Trichrome (MT) staining highlights TCPs and hyalinized collagen within and around the TCP (green circle) 14 days post‐treatment with ~0.8 J at a 3.0 mm depth. Photos courtesy of Merz Aesthetics Skin Lab.