A practical decision framework for choosing between sharp needle and blunt-tip cannula across the BiViDerma indication map — with anatomical safety considerations and a sizing reference.
Default to cannula when…
The injection plane traverses or is adjacent to named arteries.
The treatment area requires broad, even distribution (cheek, jaw, NLF).
The patient is anti-coagulated or bruise-prone.
You're treating a long linear vector with a single entry point.
Needle is acceptable when…
— Precise periosteal bolus is required (chin tip, zygomatic apex).
— Isolated short wrinkles or lip border.
— Tiny corrections at review (< 0.05 ml).
— Mucosal lip body where cannula entry is impractical.
Never inject without aspiration when using a needle
Aspirate, hold 5 seconds, observe for flash-back. Negative aspiration does not exclude vascular position but reduces risk meaningfully. Cannula does not require aspiration — the blunt tip displaces vessels rather than penetrating them.
Koretreat Market SAS · ARCSA-2023-3.3-0000041For clinical use
KKORETREAT
TQ-014 · Cannula vs needle02 / 06
Anatomy · vascular danger zones
Where the vessels live.
High-risk vessels (red on diagram)
Supratrochlear / supraorbital. Glabella and forehead. Anastomose with retinal circulation — blindness risk.
Angular / facial. Runs along the nasolabial fold from oral commissure superiorly. Highest occlusion-event reporting site.
Infraorbital. Foramen lies on a vertical line from the medial limbus, 1 cm below the inferior orbital rim. Tear-trough territory.
Transverse facial. Runs anteriorly from the parotid across the zygomatic arch. Cheek augmentation territory.
Mental. Exits the mental foramen on the vertical line below the second premolar. Chin and marionette territory.
Dorsal nasal. Mid-line nasal dorsum. Nasal correction territory; very high consequence (retinal).
Clinical · Cannula vs needlev3.0 · 2026
KKORETREAT
TQ-014 · Cannula vs needle03 / 06
Cannula-preferred zones
Where the blunt tip wins.
Zone
Cannula
Entry point
Plane
Volume / side
Temple Hollows, lateral brow lift
22G × 70 mm
Inferior to zygomatic arch, lateral canthus
Supraperiosteal
0.5 – 1.0 ml
Cheekbone Malar projection
25G × 50 mm
Pre-jowl sulcus or zygomatic arch
Supraperiosteal · deep fat
0.8 – 1.5 ml
Tear trough Infraorbital hollow
25G × 38 mm
Lateral cheek, 2 cm inferior to lid
Pre-periosteal
0.2 – 0.5 ml
Nasolabial fold
25G × 50 mm
Cephalic to fold apex
Deep dermis · SMAS
0.4 – 0.8 ml
Marionette
25G × 50 mm
Lateral commissure
Deep dermis
0.3 – 0.6 ml
Jawline Contour, pre-jowl
22G × 70 mm
Pre-jowl notch · gonial angle
Supraperiosteal
1.0 – 2.0 ml
Chin (volumising)
22G × 50 mm
Lateral chin
Supraperiosteal
0.5 – 1.5 ml
Cannula handling pearls
Pre-dilate the entry hole with a 23G sharp needle one gauge larger than your cannula. Inject on retraction only, never on advancement. Move the cannula continuously when injecting — pausing creates a bolus that doesn't blend.
Clinical · Cannula vs needlev3.0 · 2026
KKORETREAT
TQ-014 · Cannula vs needle04 / 06
Needle-acceptable zones
Where the sharp tip earns its place.
Zone
Needle
Technique
Plane
Volume / side
Lip vermillion border
30G × 13 mm
Linear threading along border
Submucosal
0.1 – 0.3 ml
Lip body Hydration only
30G × 13 mm
Serial micro-puncture
Submucosal
0.2 – 0.5 ml
Cupid's bow
30G × 13 mm
2 punctate boluses, 0.02 ml each
Submucosal
0.04 – 0.08 ml
Periosteal chin tip
27G × 25 mm
Aspirate. Single bolus on bone.
Supraperiosteal
0.3 – 0.8 ml
Pre-auricular hollows
27G × 25 mm
Fanning, retrograde
Deep fat
0.3 – 0.5 ml
Isolated NLF wrinkles Touch-up only
30G × 13 mm
Linear threading, retrograde
Mid dermis
0.05 – 0.15 ml
Mandatory needle hygiene
One needle per site change.
Aspirate before each bolus.
Slow injection: < 0.3 ml/min.
Maximum 0.1 ml per bolus in vascular territory.
Never use a needle for
Glabella deep injection (use cannula or thread).
Nasal dorsum / tip (cannula only, retinal risk).
Temporal hollow deep plane.
Patients with prior facial vascular event.
Clinical · Cannula vs needlev3.0 · 2026
KKORETREAT
TQ-014 · Cannula vs needle05 / 06
Sizing reference
Gauge, length, indication.
Cannulas
Gauge
OD (mm)
Typical lengths
Primary use
Pairs with BiViDerma
22G
0.72
50 / 70 mm
Deep volumising — temple, jaw, chin
V
25G
0.51
38 / 50 mm
Cheek, NLF, marionette, tear trough
III · I
27G
0.41
38 mm
Lip body, fine lines, peri-orbital
I
Needles
Gauge
OD (mm)
Typical lengths
Primary use
Pairs with BiViDerma
27G
0.41
13 / 25 mm
Periosteal bolus — chin, zygoma
V
30G
0.30
13 mm
Lips, fine lines, touch-ups
I
32G
0.23
4 / 13 mm
Skin booster, intradermal hydration
I (diluted)
Matching the cannula to the product
High-density products (BiViDerma V, G′ ~540 Pa) demand 22G — anything finer creates back-pressure and inconsistent flow. Medium (III) flows cleanly through 25G. Light (I) is the only variant that runs smoothly through 27G and 30G needles. Match or be frustrated.
Clinical · Cannula vs needlev3.0 · 2026
KKORETREAT
TQ-014 · Cannula vs needle06 / 06
Safety · complications
When something goes wrong.
Setting up the room
Hyaluronidase 1500 U vial within arm's reach. Verify expiry.
Aspirin 325 mg available.
Warm compress source (microwave or heating pad).
Eye chart and pen torch nearby.
Camera or phone ready for documentation.
Direct line to a hospital emergency department in your call log.
Vascular event — first 4 minutes
Stop. Acknowledge it aloud to the patient.
Hyaluronidase 200–450 U at the territory.
Firm massage to disperse.
Warm compress.
Aspirin 325 mg chewed (unless contraindicated).
Reassess in 60 min. Repeat hyaluronidase as needed.
Reporting
Pharmacovigilance
farmacovigilancia@koretreat.com — within 48 hours of any adverse event.
Clinical hotline
+593 988 089 010 — 24/7. For real-time decision support during an event.
ARCSA
Koretreat files the regulatory notification on the practitioner's behalf using your incident report.
This document is a technique reference. It does not replace formal training. Practitioners must complete certified hands-on training before injecting BiViDerma. Koretreat conducts certification courses every quarter — contact training@koretreat.com.
Koretreat Market SAS · ARCSA-2023-3.3-0000041TQ-014 · v3.0 · 2026