January 30, 2023

BOTOX injection male forehead

The ‘bread and butter’ of any medical aesthetic practice is botulinum toxin or Botox® treatment in the upper face, but are aesthetic clinicians truly familiar enough with the anatomy to avoid side effects, whilst also maximising and optimising product efficiency?

In this blog, Dr Tim Pearce takes you on an anatomical tour of the key muscles we can inject with botulinum toxin to relax wrinkles in the upper-third of the face. He advocates avoiding paint-by-number injection techniques and provides top tips to avoid complications like eyelid ptosis and Spock brow.

Your consultation should include asking your patient to move their face so you can assess the muscle movement; giving them a mirror or asking them to copy you can help. As you do this, look at each area in isolation, and remember to feel the movement. If you place your finger on the area you plan to treat, as the patient makes expressions, you can determine the direction or pull of movement to identify facial vectors.

Do you feel anxious about causing complications? Many clinicians feel so overwhelmed with the thought of causing a vascular occlusion that it stops them growing their aesthetics business. Dr Tim is currently hosting a webinar series to help you overcome your fear of complications so that you can uplevel your knowledge, and increase your CPD-certified learning to build a successful aesthetics business. Sign up here >>

Horizontal forehead lines and frontalis

Forehead Botox Frontalis Injection SitesWhen starting out as an aesthetic clinician, the frontalis muscle is arguably the most difficult area to treat. It causes much confusion for practitioners because it is highly variable, not only in terms of differing anatomy between individuals, but also between men and women.

There can be significant differences across the population – some people have small foreheads, and some are long. The muscles can appear as two separate plates or as a singular plate. In men, for example, the frontalis muscle often goes up higher into and beyond the hairline, (or where it should be if the hairline has receded).

As well as a different shape between men and women, the aesthetic goal is usually different. When treating females, the aim is to lift the eyebrows, to create a feminine arch, but if you create a feminine arch in a man, it can look sinister or simply odd. Similarly, if you perform a more masculine treatment pattern on a female, it may result in no lines on the forehead, but will likely cause a brow ptosis which drops the position of the eyes.

To accommodate different aesthetic goals for different patients, who may have wildly different anatomy, Dr Tim affirms that you must learn a set of principles that allow you to treat any forehead. This means not relying on simple injection patterns or one-size-fits-all techniques that you apply to any forehead because it is never going to work.

When treating the frontalis muscle, the aim with most patients is partial treatment, so there is always some movement which is required to support the eyebrows. If you over treat the middle, you get a medial brow ptosis and a lateral brow lift – the so-called Spock brow. If you over treat laterally, you can lose the arch of the eyebrow, but still have movement in the middle, leading to a sad look. If you over treat the whole of the frontalis, the patient will look very tired with flattened eyebrows. All these aesthetic complications tend to result from using a blanket approach to treatment.

Read more on this and discover Dr Tim’s best Botox brow lift injection patterns to avoid ptosis and Spock brow.

Top tips for treating the frontalis muscle with botulinum toxin

Dr Tim implores that clinicians assess each patient individually. Start by marking the areas where you do not want to inject, to avoid mistakes – creating a safety margin approximately two centimetres from the orbital rim to avoid causing a brow ptosis or heaviness.

Similarly, decide where you may be wasting botulinum toxin if you inject; if there is an aponeurosis and you can see there is no muscle activity when you assess movement, mark it so you do not waste valuable product. Once you have drawn on all the areas where you do not want to inject, there is usually a relatively small area to optimally treat.

If you are treating a patient for the first time, expect to do it in stages, as opposed to one single treatment session, says Dr Tim; take them on a journey until you know what works for them. Treat as you see fit, but leave room for improvement or correction with a small top-up at a follow-up appointment. There are fewer options if you over treat in one go and cause a side effect than if you work more cautiously.

Of course, top-ups may not become the norm once a patient profile is established. Dr Tim asks whether Botox® follow-ups should be routine and how to stop patients from asking for ‘top-ups’ or extra botulinum toxin treatment.

Frown lines and corrugators

The corrugator supercilii is a muscle that runs from the periosteum, medially, all the way up through all the different tissue layers including the fat pads and touches the dermis on the far lateral point of the eyebrow. Once you understand the route of the muscle, you see how you can inject deeper medially, getting more superficial as you reach the lateral part of the brow.

Vectors in the face differ between patients – in some, if you ask them to frown, their corrugator muscles will squeeze in a relatively flat line, whereas others might have a strong downward vector. This can affect whether you choose to treat the corrugators when you are treating the frontalis, for example, and, as a rule of thumb you always treat the two together. However, if the patient is not a significant frowner, and lacks a downward pulling vector, then it may not be necessary. Conversely, if you only treat the frontalis, which normally lifts the muscle up, and leave the corrugators untreated, any existing downward vector can cause an increased or angrier-looking frown in that individual.

Injecting the corrugator is responsible for most cases of eyelid ptosis; the reason being that as you embark on injecting the neurotoxin more laterally, you get closer to the supratrochlear foramen where there is an artery and a nerve that run through the septum. In theory, if you place botulinum toxin near here, it may relax the levator palpebrae or eyelid muscle thus causing a ptosis. As you get closer to this high-risk point, you can inject more superficially, achieve a good aesthetic result, but by ensuring there is a fat pad in between the injection and the supratrochlear foramen, you can reduce the risk of eyelid ptosis.

Also worth a mention is the depressor supercilii. This is a little muscle that is more medial than the corrugator and pulls straight down. Many believe it is a component of orbicularis oculi and not a separate muscle, but it is a medial depressor. Clinically, however, it probably does not matter because if you are treating the medial part of the corrugator supercilii, you are very likely to also be treating depressor supercilii.

Forehead glabellar lines


The procerus is the medial muscle that runs up from the bridge of the nose and usually pulls the glabella down towards the nose. Like the frontalis, it is hugely variable across individuals.

Clinicians ought not to get into the habit of injecting the same number of units of botulinum toxin for each patient, warns Dr Tim. This could be a waste as the muscle can be almost absent in some patients. Yet, in a small percentage of patients it can be the dominant muscle, more so that the corrugators – usually presenting with a crease that runs over the top of the nose due to the increased downward pull from procerus.

Crow’s feet and orbicularis oculi

The orbicularis oculi muscle causes crow’s feet or lateral canthal lines (although some of them can be caused by the zygomatic muscle). It is a circular muscle that runs underneath the skin, very close to the surface around the eye and its circular nature makes it complex because it can pull in various directions.

This muscle is in a tug of war with the eyebrow and the frontalis muscle. The frontalis is pulling up and orbicularis oculi is pulling down. If you relax orbicularis oculi with botulinum toxin, you will achieve a lift in the eyebrow which can be used for a subtle eyebrow lift. Similarly, it is an option for the treatment of brow ptosis if you have over treated the frontalis.

In the cheek, orbicularis oculi is an accessory muscle for cheek elevation. Thus, if you over treat it, the smile can look less real because the cheek moves and elevates less which is required for a genuine Duchenne smile.

Dr Tim’s top tip for injecting the orbicularis oculi muscles is to inject more superficially – depth should be 1-1.5mm so the needle is sitting just on top of the muscle. This will minimise bruising and protect everything that lies underneath the muscle, including the zygomatic muscles. If you inject too deeply and affect the zygomatic muscles with your injections, each time the patient smiles there will be asymmetry which has the appearance of having had a stroke.

Why not download this free helpful guide from Dr Tim on 26 essential injection patterns for botulinum toxin. Consider additional eLearning options with Dr Tim including Botox® in Aesthetic Medicine (Foundation) and botulinum toxin complications mastery.

If you have any questions or comments about treating the upper third of the face with botulinum toxin, you can find Dr Tim Pearce on Instagram.

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Aesthetics Mastery Show

Muscle anatomy – how to avoid side effects and maximise BOTOX efficiency

In this Aesthetics Mastery Show, Dr Tim gives an anatomical tour of the key muscles injected for upper-third Botox treatments, including the frontalis, corrugator, depressor supercilii, procerus, and orbicularis oculi. Watch the full Aesthetics Mastery Show here.

The show has had a massive response with over 286k views and has generated 179 comments so far, including feedback from both practitioners and clients.

Nayantara Jnananand said:

“Very practical and detailed. A MUST WATCH to learn to be an experienced and safe aesthetic injector. Thanks you very much for making them so freely available. I really really appreciate it!!!!”

Francesca Sharif added:

“I have watched this video so many times over the last few months! i just love how you both discuss each subject”

Kimberly Kelly said:

“You are both are incredibly helpful! This reel was so informative. It is a gift to educate and instruct via videos and you and your wife are amazingly good at it! Your suggestion to feel the vector of the corrugator muscle was the key for understanding muscles of the face. it just connected everything for me THANK YOU!”

Alek Fisher gave his personal perspective on treatment:

“Thank you for pointing out the small but very important depressor supercilii muscle, I had been receiving a heavy dose in my medial corrugators and would always come away still feeling tension in the inner corners of my brow and didn’t know why – until I learned it was the depressor supercili that needed to be treated more specifically and superficially. Once I added that injection site I noticed an immediate and obvious improvement and lift in my inner brows and now I look and feel more serene and less angry!! Very valuable info in this video!”

Read more questions and answers or join in the debate on our YouTube channel.

Dr Tim Pearce eLearning

Dr Tim Pearce MBChB BSc (Hons) MRCGP founded his eLearning concept in 2016 in order to provide readily accessible BOTOX® and dermal filler online courses for fellow Medical Aesthetics practitioners. His objective was to raise standards within the industry – a principle which remains just as relevant today.

Our exclusive video-led courses are designed to build confidence, knowledge and technique at every stage, working from foundation level to advanced treatments and management of complications.

Thousands of delegates have benefited from the courses and we’re highly rated on Trustpilot. For more information or to discuss which course is right for you, please get in touch with our friendly team.

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