Botox injections are a popular cosmetic procedure, but many people are unsure of how far the needle goes. To ensure the best results, it is important to understand the anatomy of the area being injected and the size of the needle being used. Even if the masseter muscle is reached, a lack of deep enough injection can cause the lower parts of the muscle to move normally while the upper part is relaxed, creating a “squirrel” appearance. Doctors should try to inject at the site where the muscle attaches to the bone, using a ½ longer needle for best results.
A 32-gauge half-inch needle (Air-Tite products) minimizes injection discomfort. In the periorbital areas, it is injected obliquely into the skin to reduce the possibility of deep injections or even injuries in case the patient moves suddenly. Pinching up or gently rubbing the adjacent skin during injection minimizes patient discomfort by distracting the patient during injection and “confusing the sensory sensation of the injection” (Figure 95). We recommend pre-marking the areas to be injected and use bright lighting and magnification to avoid injury to the vessels of the eyelid.
We rarely use topical anesthetics, and some suggest a reduced duration of effect in patients treated with topical anesthetic prior to injection. Injections should be given into the planes of the subcutaneous tissue to avoid underlying muscular and neurovascular structures. This reduces patient discomfort and decreases risks of bruising and deep spread. In general, injections can be given obliquely or perpendicular to the skin, but in orbicular areas it is essential to inject at as flat an angle as possible due to thinness of eyelid skin and pointing away from eye.
It is also useful when injected into lower orbicular areas to stretch skin, which helps place Botox in subcutaneous plane. Botox should be avoided in upper central eyelid to prevent ptosis and over lower oblique in lower eyelid to prevent diplopia. A 30-32 gauge is an appropriate Botox needle size, and they vary little in terms of pain or application. Injections are almost always going to be at least a little painful for patients, even when small needles are used.
And although there is some discomfort associated with Botox injections, topical anesthetics are rarely used as needles are very small and injections are given quickly. When considering Botox injections, it is important to ask about cost of therapy, how many doses will be needed, what size needle will be used, and how often injections have been given. Ultra-thin needles ensure expert accuracy and minimize pain and bruising in injection process. Physicians and other qualified professionals administer Botox using any 30 gauge and 32 gauge Botox needle.
Researchers have found that there is not much difference in results of pain scale for patients with injections with 30 and 32 gauge needles. It is also important for patients to understand anatomy of area being injected and depth to which needle should be inserted. For example, smallest recommended gauge for Botox injections is 32, which has needle wall thickness of 0.064 mm, while 30 gauge has thickness of 0.076 mm. The IAPAM recommends using short single-use needle such as 31, 32 gauge insulin needle when possible. Botox injections are a safe and effective way to reduce wrinkles and improve facial appearance. Understanding how far the needle goes and what size needle should be used can help ensure best results with minimal discomfort.
