# **Chapter 3 – Injection Techniques for Skin Botox (Microbotox)** This is the “art and science” of Microbotox: how to dilute, where to inject, what tools to use, and how to achieve optimal spread without side effects. --- ## **3.1 Dilution Protocols and Preparation** ### (A) Standard Reconstitution - Toxin vial: typically **100U BoNT-A**. - Dilution for Microbotox: - 100U + 5 mL saline → **2U per 0.1 mL** - 100U + 10 mL saline → **1U per 0.1 mL** - For ultra-dilute protocols (“Skin wash” or “Meso-toxin”): up to **20 mL saline**. 👉 Principle: **Higher dilution → wider diffusion → softer effect** (ideal for pores, oil, glow). --- ### (B) Injection Volume Per Site - **Micro-deposits of 0.01–0.02 mL per point**. - Multiple injections (30–100 points per face, depending on area). - Goal = evenly spread the diluted toxin intradermally like a “skin mesh.” --- ### (C) Special Mixtures - **Hybrid protocols** (e.g., Skin booster + BoNT-A): - Mix with **HA (low concentration), PDRN, exosomes**. - Maintain botulinum concentration at **~0.5–2U/0.1mL**. - Synergy: hydration, regeneration + oil/pore control. --- ## **3.2 Depth and Angle of Injection** - **Target Layer**: **Superficial to mid-dermis (~1 mm depth)**. - **Angle**: **10–15° (bevel up)** to achieve intradermal bleb. - If too deep → muscle paralysis (unnatural expression). - If too superficial → toxin leakage/whitening spots. 👉 Golden rule: **tiny bleb should be visible immediately, but resolve in 15–30 minutes.** --- ## **3.3 Injection Tools** ### (A) Standard Needles - **30G needle** (0.3 mm) - Commonly used, versatile. - Precise depth control, especially in larger fields. - **31G ultra-fine insulin syringe** (0.25 mm) - Less painful, good for delicate areas (eyes, lips). - Convenient for 0.01 mL aliquots. - Less control of pressure/depth than 30G. ### (B) Multi-needle Devices - **Nappage technique injectors (dermojet, mesogun)**: - Deliver rapid, uniform intradermal injections. - Reduce injector fatigue, increase efficiency. - Costly, may cause pinpoint bleeding/bruising. ### (C) Cannula - Rarely used for Microbotox (not precise for dermal micro-points). --- ## **3.4 Regional Approaches** ### (A) Forehead - Pattern: Horizontal microinjections in **5–6 rows** across the forehead. - Depth: 1 mm intradermal. - Caution: Avoid too deep injection → risk of frozen expression or brow heaviness. ### (B) Glabella & Periorbital (Crow’s Feet) - Diluted Microbotox can soften fine lines around eyes without freezing smile. - Use **31G needle, 0.01 mL per point**, ~1 cm spacing. - Avoid orbital rim → reduce risk of diplopia. ### (C) Cheeks & T-Zone - Goal: **pore refinement and oil control**. - Injection grid: 1 cm spacing, full cheek + nose + chin. - Especially effective for patients with seborrheic skin. ### (D) Jawline - Microbotox in **jawline dermis** provides subtle tightening (“Nefertiti-like lift”). - Complementary to deeper platysma Botox if needed. ### (E) Neck - Horizontal “necklace lines”: - Intradermal blebs along each line. - Platysmal bands: - Use slightly deeper injection, but still superficial compared to classic platysmal Botox. ### (F) Décolleté / Chest - Fine crêpey wrinkles from sun damage. - Microinjections in a grid-like pattern → smoother skin quality. --- ## **3.5 Injection Patterns** 1. **Grid Technique** - Face divided into 1 cm squares. - 0.01–0.02 mL per site. 2. **Nappage Technique** - Rapid-fire multiple tiny blebs, like mesotherapy. - Useful with mesogun injectors. 3. **Point-by-Point Precision** - Manual, with insulin syringe. - Best for delicate areas (periorbital, perioral). --- ## **3.6 Clinical Pearls** - Always **prime the patient**: results are subtle, natural, last ~2–3 months. - Use **ice packs, topical anesthetic, or vibration devices** to minimize pain. - Avoid massaging injected areas → prevents toxin spread to unintended structures. - Combine with **energy-based devices** (RF, lasers) **before** Microbotox (not after, to avoid diffusion changes). - Document dilution, dose, injection map → ensures reproducibility. --- ## **Key Insights from Chapter 3** - Skin Botox is about **precision + diffusion**. The physician must master **depth (1 mm), dose (0.01–0.02 mL), and distribution (grid-like pattern)**. - Tools matter: **30G needle = control**, **31G insulin syringe = comfort**, **multi-needle injector = efficiency**. - Each region of the face/neck requires a **different approach**: pore control, wrinkle softening, subtle lift, or rejuvenation. - Success = **uniform skin quality improvement** without frozen expressions. ---