Medical Aesthetics Injectable Protocol Atlas
Botulinum toxin ABO / Dysport Dose ReferenceSpeywood Units; expand table
Unit note: Protocol doses in this atlas use onabotulinumtoxinA (onaA) as the main reference. abobotulinumtoxinA (aboA, Dysport / Alluzience family) uses Speywood Units. Product units are not directly interchangeable; this table follows the Alluzience consensus by area and should not be converted with a single fixed multiplier.
| Indication | onaA reference | aboA / Alluzience (Speywood) | Injection-point reference |
|---|---|---|---|
| Glabellar lines | 12-40 U (typical about 20 U) | Total 50 U: procerus 10 U + each corrugator head 10 U + tail 10 U | 5 points; 1 procerus + 2 corrugator points per side |
| Crow's feet | 6-15 U per side | Total 30-60 U, 5-10 U per point (15-30 U per side) | 3 points per side around lateral canthus; up to 6 in severe cases, low dose medially to spare zygomatic muscles |
| Forehead lines | 8-25 U | Total 20-40 U, 2.5-5 U per point | 4-8 points; keep ≥2 cm above supraorbital rim and avoid lower frontalis over-treatment |
| Lateral brow lift | 1-6 U | Total 20-40 U, 5-10 U per point; WIFI point intradermal 2.5 U | Lateral pars orbicularis + lateral frontalis; pars orbicularis needle depth about 6 mm |
| Lower-lid lines | 0.5-2 U per side | Total 5-6 U, 1-2 U per point (2.5-3 U per side) | 1-3 points, 2-3 mm below lashes; snap test <2 s before treatment |
| Eye opening | 0.5-1 U per side | Total 4-6 U, 1-2 U per point | 2-3 superficial points near the lower-lid margin |
| Bunny lines | 4-8 U (up to 10 U) | Total 10-20 U, 2.5-10 U per point | 1-3 points in transverse nasalis |
| Drooping nasal tip | 2-6 U | 10 U at nasal spine; if LLAN is hyperactive, 10 U per side beside alar base | Deep injection at nasal spine, vertical needle entry |
| Perioral lines | 1-5 U | Total 4-12 U, 1-2 U per point | 4 symmetric points above vermilion border; lateral points ≥1.5 cm from oral commissure |
| Downturned mouth (DAO) | 2-4 U per side | Total 5-10 U | 1-2 DAO points, 1 cm lateral and 1 cm inferior to commissure; pinch muscle |
| Masseter hypertrophy | Total 15-40 U | 40-80 U per side, 5-10 U per point | 3-5 pyramidal points per side; below tragus-commissure line, avoid zygomatic muscles |
| Mentalis dimpling | 4-10 U | 5-10 U per point | 1-3 deep points near lower midline, angled inferior-lateral to spare depressor labii inferioris |
| Cheek hollow line / high risorius tone | No dedicated onaA entry | 1-2 U per point | 1-2 intradermal points per side, ≥1 cm posterior to modiolus, often combined with filler |
| Platysma bands | 6-12 U per band (max 60 U) | Typical total 100 U; about 20 U per band, 5-10 U every 2 cm | Patient seated, pinch band; inject from mandibular border downward every 2 cm to mid-band, superficial intramuscular |
| Decolletage lines | No dedicated onaA entry | Max total 120 U, 2.5-5 U per point | Along pectoralis-related creases; not routinely recommended by consensus, may be paired with platysma treatment |
Pre-treatment periocular functional screen: Before botulinum toxin treatment of the glabella, forehead, brow, crow's feet, or lower lid, assess brow position, upper-lid skin redundancy, lid closure and Bell's phenomenon, tear film / dry-eye symptoms, and pre-existing eyelid malposition. Patients with lagophthalmos, facial palsy, neurotrophic keratopathy, marked dry eye, or ectropion have a higher risk of functional complications and require cautious assessment.
Periocular safety boundary: Consider upper-lid or brow ptosis, incomplete closure and exposure keratopathy, epiphora from impaired lacrimal-pump function, and rare diplopia from spread to extraocular muscles. Avoid visible vessels near the medial canthus, particularly the angular vein. This section supplements safety assessment for aesthetic periocular treatment only; therapeutic ophthalmic indications such as blepharospasm and hemifacial spasm are outside the atlas scope.
Sources: Alluzience consensus, ASJ 2024, DOI 10.1093/asj/sjad222; Kundu et al. masseter review, DOI 10.1111/jocd.14858; periocular safety supplement, Lanzl et al. 2026 (L3 ophthalmology CME), DOI 10.1007/s00347-026-02511-y.
Needle & Cannula Selection Guidancegauge · trajectory · resistance · delivery control
Bottom line: Cannula selection starts with the full trajectory. Define the entry, target plane, endpoint, and direction of advancement; then choose length, gauge, flexibility, and opening position. During advancement, use changes in resistance as continuous feedback. During retrograde placement, control opening orientation, delivery pressure, and volume per pass together.
Key findings
A 38-70 mm cannula crosses several vascular segments
Common filler cannulas are approximately 38-70 mm (1.5-2.75 inches) long. Multipoint dissections in 49 cadavers found up to 23% variation in diameter along a single facial or periorbital artery. One complete pass may run alongside 2-3 segments of the same vessel with different diameters. Length selection should map the entry, endpoint, plane along the entire pass, adjacent arterial course, and any confined or fibrotic segment. Match length to the planned route and keep probing within it.
Direction of advancement changes how the cannula meets a vessel
Use retrograde injection near superficial arterial branches, tight anatomical planes, or fibrotic tissue: advance the cannula beyond the target, then release product during withdrawal. In the central face and periorbital region, antegrade movement against arterial flow approaches a progressively larger proximal vessel. The cannula becomes smaller relative to the lumen, potentially increasing vessel trauma or entry.
A side port moves product release away from the forward axis
A terminal opening releases product forward; a side port releases from the cannula wall. A side port combined with retrograde injection can improve directional control and reduce the chance that the opening directly faces a vessel during advancement. Performance depends on port orientation, tip depth, operator technique, and individual anatomy. Before insertion, identify the port's orientation relative to the hub and maintain the intended direction throughout withdrawal.
Resistance and gliding describe real advancement better than one puncture-force value
A cadaveric experiment compared 22 / 25 / 27 / 30G cannulas and needles in 4 fresh-frozen cadavers plus a second verification site in a fresh cadaver. At the same gauge, minimum arterial penetration force was approximately 0.1-0.4 N for needles and 0.5-1.0 N for cannulas. Cannula advancement through the subdermal nasolabial fold required 0.5-2.2 N, at times exceeding the force needed to penetrate an exposed artery. Cannulas frequently rolled over, under, or around the vessel; some vessels required up to 30 attempts and external fixation before entry. Needles entered without repeat attempts. A sudden rise in resistance should trigger an immediate stop and redirection, preserving the cannula's ability to glide along fascia or around a vessel.
Gauge changes stiffness, maneuvering space, and dose control together
Within comparable designs, a larger-diameter 22G cannula requires more arterial and tissue penetration force and has greater stiffness. Smaller-diameter 27G and 30G cannulas require less advancement force and provide more flexibility and maneuvering room in confined spaces. Example outer diameters are approximately 0.41 mm for 27G and 0.72 mm for 22G. In tight regions such as the infraorbital hollow and nose, consider a 27G cannula for greater maneuvering room; its higher delivery resistance may also help control volume per pass. Differences among 3 cannula brands showed a trend, P=.061.
Selection guidance
| Decision point | How to apply it |
|---|---|
| Plan the trajectory | Record the entry, endpoint, target plane, direction, and critical structures along the entire route. Choose a length that covers this route and recheck plane and resistance in segments during a long pass. |
| Select the gauge | In dense or confined spaces, assess flexibility and room to redirect. Where tissue space is wider or product delivery demands are higher, evaluate shaft stiffness, internal diameter, and filler rheology together. |
| Select the opening | For directional placement, evaluate a side-port design and identify its orientation marker. Maintain port direction during withdrawal so rotation does not shift the release vector. |
| Respond to resistance | Stop when resistance rises abruptly, then re-establish plane and direction. Avoid sustained force through fixed vessels, branching points, ligaments, or fibrotic tissue. |
| Control delivery | Use slow, low-pressure delivery, small aliquots, and controlled withdrawal. Execute device, trajectory, port direction, and delivery action as one decision. |
Evidence and confidence
| Study | Design and main finding | Level |
|---|---|---|
| Yi et al. 2025 | Bilateral, multipoint vascular measurements in 49 Korean / Thai cadavers. Mean facial and periorbital arterial diameters were approximately 0.7-2.1 mm, with up to 23% variation along one vessel. The study provides a static anatomic baseline; its gauge model awaits clinical validation. | L3 anatomy |
| Siperstein et al. 2023 | 4 fresh-frozen cadavers, a second site in 1 fresh cadaver, 3 cannula brands, 4 gauges, plus live nasolabial-fold training resistance data. Same-gauge cannulas required more force than needles to penetrate an artery; gliding, flexibility, and tissue resistance directly shaped advancement. The brand comparison yielded P=.061 and no rank order. | L3 experimental |
| Yordanov 2025 | Adds 38-70 mm length, complete trajectory, antegrade / retrograde direction, terminal / side opening, and port orientation to device selection. The guidance draws on anatomical research, prior consensus, and clinical experience. | L3 expert guidance |
| Goodman et al. 2020 | Consensus on filler-related embolic visual loss. It supports combined control through high-risk anatomy, target-plane knowledge, slow low-pressure delivery, small aliquots, and controlled movement. | L2 consensus |
| Yi et al. 2026 | Vessel caliber contributes one component of device selection, while cadaveric measurements provide an anatomic baseline. Clinical selection also considers dynamic anatomy, technique, and patient assessment. | L3 expert interpretation |
Sources: Yi et al. 2025 cadaveric anatomy study (L3), DOI 10.1093/asj/sjaf070; Siperstein et al. 2023 penetration-force study (L3), DOI 10.1093/asj/sjad149; Yordanov 2025 (L3), DOI 10.1093/asj/sjaf229; Goodman et al. 2020 safety consensus (L2), DOI 10.1093/asj/sjz312; Yi et al. 2026 (L3), DOI 10.1093/asj/sjag086.
Clinical combinations fall into three types: Material combo (different materials sharing one site, e.g. volume + skin quality), Regional combo (cross-region synergy producing a whole-face effect, e.g. periorbital frame, outer-frame lift), and Layered (same-session placement by plane, deep to superficial, structure before skin). Each component is clickable for its full protocol.
Real injecting usually advances by anatomic plane, deep to superficial: build bony support in the deep plane, restore volume and ligaments in the mid plane, then refine skin quality superficially. This logic spans indications and regions and closely follows clinical practice. Below is a full-face stratification; click any protocol for its six elements.