HIFU Neck Protocol: The Thyroid Box and Thin-Skin Rules

The neck lifts well with HIFU and forgives nothing. Thyroid tissue, the thin platysma layer and the laryngeal prominence make the neck the one zone where cartridge discipline is a safety issue, not a results preference.

Cartridge Map for the Neck

• 3.0 mm: the working depth — platysma and subcutaneous layer, lateral neck columns
• 1.5 mm: finishing passes over the anterior neck where skin is thinnest
• 4.5 mm: reserved for the jawline-adjacent upper neck only — never below the thyroid cartilage

The Thyroid Box: Draw It, Respect It

1. Mark the midline box from thyroid cartilage to sternal notch — no shots inside, any depth
2. Stay lateral: two safe columns run along the sternocleidomastoid muscles
3. Pain near the larynx or trachea is anatomy speaking — reposition, never push through

Session and Expectation Frame

Neck sessions use fewer lines than full-face work (150-250 typical) with results at 8-12 weeks. Neck skin shows over-treatment as prolonged redness and striping — conservative line density always wins. Repeat eligibility follows the annual rule from the 12-month calendar; cartridge interplay with the lower face is in the jawline protocol. Multi-cartridge platforms like the New Doublo 2.0 cover both depths in one session.