Botulinum Toxin Flashcards
What are the absolute contraindications to Botox?
- Prev allergy to BT
- Psychological (BDD)
- Infection at treatment site
- NM disorders e.g. myasthenia, AL, eaton-lambert
- Dysphagia/aspiration history
- Pregnant or breastfeeding
What are the relative contraindications to botox?
- Less than 18yrs old
- Anticoagulants, antiplatelets, vit E
- Aminoglycosides (enhance effects of botox)
- Calcium antagonists (antagonise effect of botox)
What has gone wrong in glabellar treatment if there is medial brow ptosis?
injection points too high
What has gone wrong in glabellar treatment if there is lateral brow ptosis?
injections too lateral
When can brow ptosis happen with frontalis treatment?
Low product placement
Overtreatment of frontalis
Poor patient selection = low set eyelids, hooding or hyperkinetic frontalis
How can patients get spock brow (mephisto sign)?
If frontalis placement is too medial - caused by active lateral frontalis
Can also happen in tails of corrugator if product is placed too deep/lateral
Why can crows feet treatment cause diplopia?
medial migration of toxin to lateral rectus
How can OO injections affect the smile?
Deep injections of inferior point can cause paralysis of zygomaticus muscles
How can OO treatment cause dry eye?
Deep injections of superior point
Due to affecting the lacrimal gland
What are the cautions to be aware of when treating upper lip lines?
Risk using straw or eating from spoon could be difficult
Lengthening of upper lip
Administer close to vermillion border to prevent zygomaticus minor
Superficial injections means deep fibres remain intact preserving function
What is the history of botulinum toxin?
1985: Emile van Ermengem isolates clostridium botulinum
1944: Schantz isolates BT Type A
1973: Scott treats strabismus with Type A
1987: Jean Carruthers notices skin effects
1990: Alastair Carruthers publishes studies for aesthetic use
How does botulinum toxin work to cause muscle paralysis?
Inhibits release of acetylcholine at NMJ
To become active, the molecule is endogenously cleaved by bacterial proteases into 2 fragments
- light chain (50kDa) and heavy chain (100 kDa)
Botox binds presynaptically to cholinergic nerve terminals halting release of ACh
What type of toxin is preferred for aesthetics and why?
Type A
Longer duration of action and ease of production
Why is botox only temporary?
SNAP 25 gradually regenerates = restoring muscular contractility over time
What is the duration of action of botulinum toxin?
Effects begin within 3-4 days and peak at 14-30 days
Lasts approx. 3-4 months
Metabolised by body within 28 days
Top ups should be 2-4 weeks after initial treatment
What factors can affect immunogenicity of botox?
Manufacturing process
Antigenic protein load
Presence of accessory proteins
Treatment related factors = overall toxin dose, tiing of adjustment dose injections, prior vaccination exposure
What is the difference in dosing between botox, bocouture and azzalure?
Botox and Bocouture are 1:1
Azzalure 2.5 to 1
Which brand of botulinum toxin does not need to be refrigerated when not constituted?
Bocouture
- once reconstituted will need refrigerated (2-8)
How much saline & botox is used for reconstitution?
100 units vial into 2.5ml saline
4 IU per 0.1ml
What is the function of the superior part of orbicularis oculi?
depresses lateral brow
= relaxation of this part can cause subtle brow lift
Which muscle elevates the superior eyelid?
Levator palpebrae superioris
What is the action of depressor anguli oris?
Depresses corner of mouth
What are some immediate complications which can result after botulinum toxin?
Fainting
Hypoglycaemia
Allergy
Bruising, tenderness
Headache
Flu-like symptoms
What are some later complications which can result after botulinum toxin?
Infection
Asymmetry
Lower third/neck = dysphagia + dysphonia
Pseudoherniation
Mephisto brow = inadequate frontalis
Eye complciations = ptosis, extropion, diplopia, blurred vision, dry eye
What happens if we do not treat masseter adequately?
Muscle spasm
Need to treat both deep and superficial fibres
What are the causes of eyebrow ptosis?
- Frontalis treated too inferiorly
- Patient relies upon frontalis tone to keep eyes open
- Excessive eyelid hooding
What causes lower eyelid ectropion?
Overtreatment of palpebral portion (inferior) of orbicularis oculi muscle
What causes diplopia?
Paralysis of lateral rectus muscle
What causes dry eye following botox?
Toxin placed too deep in upper periorbital point and may diffuse into lacrimal gland
