Treating Crow's Feet with Botox: Techniques and Tips

Treating crow's feet with Botox remains one of the most commonly requested aesthetic procedures. When performed correctly, periorbital neurotoxin injections can dramatically soften lateral canthal lines while preserving the natural warmth of a genuine smile.

Understanding the Anatomy of Lateral Canthal Lines

Crow's feet, clinically known as lateral canthal lines, form in the periorbital region due to the repeated action of the orbicularis oculi muscle. This circular muscle surrounds the eye and is responsible for both voluntary movements like blinking and involuntary expressions such as squinting and smiling.

The orbicularis oculi consists of three anatomically distinct portions:

• Orbital portion: The larger, peripheral section extending beyond the bony orbit
• Palpebral portion: The thinner section within the eyelids themselves
• Lacrimal portion: The deep section associated with tear drainage

Why Crow's Feet Develop

Lateral canthal lines develop through a combination of intrinsic and extrinsic aging factors. Contributing factors include:

• Chronic UV exposure and photoaging
• Loss of dermal collagen and elastin with age
• Decreased skin thickness in the periorbital area
• Bone resorption in the lateral orbital rim
• Fat pad descent and volume loss

Patient Assessment for Periorbital Treatment

Thorough patient assessment is crucial before treating the periorbital area with neurotoxin. Key assessment points include:

• Severity grading: Classify lines as mild, moderate, or severe
• Dynamic vs. static lines: Determine whether wrinkles appear only with movement or persist at rest
• Skin quality: Assess texture, thickness, and photoaging
• Asymmetry: Note any differences between left and right sides
• Lateral brow position: Evaluate whether the patient has brow ptosis

Injection Technique and Patterns

The standard approach for treating crow's feet involves a three-point injection pattern placed lateral to the orbital rim:

1. Superior injection: Placed approximately 1.5 cm lateral to the orbital rim, aligned with the lateral canthus
2. Middle injection: Positioned directly lateral to the lateral canthus, 1-1.5 cm from the orbital rim
3. Inferior injection: Located 1.5 cm lateral to the orbital rim, inferior to the lateral canthus

Dosing Guidelines for Crow's Feet

Botox (onabotulinumtoxinA):

• Total per side: 6-15 units
• Per injection point: 2-5 units
• Typical starting dose: 12 units per side (4 units × 3 points)

Dysport (abobotulinumtoxinA):

• Total per side: 18-45 units
• Conversion ratio approximately 2.5-3:1 compared to Botox

Achieving Natural Results

The hallmark of excellent crow's feet treatment is softening lines without creating a frozen appearance. Strategies include:

• Conservative initial dosing—start moderate and increase at follow-up if needed
• Avoid over-treatment—some residual movement during maximum smile is desirable
• Respect the orbital rim boundary—never inject medially over the orbital bone
• Consider the whole face for balanced results

Common Pitfalls to Avoid

• Injecting too medially: Can cause diplopia, ptosis, or difficulty closing the eye
• Treating too inferiorly: May weaken the lower lid and cause ectropion
• Excessive dosing: Results in an unnatural appearance
• Ignoring facial asymmetry: Symmetric dosing on asymmetric faces worsens imbalance

Expected Outcomes

• Onset: Initial effects visible at 3-5 days
• Peak effect: Maximum results at 10-14 days
• Duration: Typically 3-4 months

For patients with significant static lines, discuss adjunctive treatments such as laser resurfacing or microneedling to address the textural component that neurotoxin alone cannot improve.