Chapter 4
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4.1 Introduction
Topical BNT treatment is a wish far away from realization. BNT needs to be injected to exert its action. There are basically two ways to inject BNT: the standard technique and the microin- jection technique.
4.2 Standard Technique
The standard technique is used if target areas are well-defined and there is a minimal risk of adverse reactions. BNT in a volume of 0.05 ml or more is injected with a 30 or 32-gauge needle perpendicular or beveled into the skin. The stan- dard technique is especially recommended for the mm. corrugatores. The periosteum should not be touched.
4.3 Microinjection Technique
The microinjection technique is used to adminis- ter low doses of BNT very superficially. BNT ap- plied by microinjection technique in the crow’s feet area will decrease the risk of an involuntary co-treatment of the m. zygomaticus major. The microinjection technique follows an intrader- mal approach. Small amounts of BNT (less than 0.025 ml) are injected approximately 1 cm apart, very superficially, in a technique comparable to
Contents
4.1 Introduction . . . 25
4.2 Standard Technique . . . 25
4.3 Microinjection Technique . . . 25
4.4 Other Techniques . . . 26
Injection Technique
Berthold Rzany
26 Berthold Rzany
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the intradermal skin test. Here the 32 gauge or at least a 30-gauge needle is highly recommended.
If done correctly a small, sometimes whitish, papule can be seen (Fig. 4.1).
4.4 Other Techniques
BNT should usually not be injected by feather- ing techniques to avoid adverse events due to the involuntary co-treatment of adjacent muscles.
Fig. 4.1. Small whitish papules after applying BNT-A us- ing the microinjection technique in the crow’s feet area
