Botox Injection for Facial Aesthetics

Botox Injection for Facial Aesthetics in Northridge, Encino, Tarzana, Granada Hills, Porter Ranch, Reseda, West Hills, Woodland Hills

History

Botulinum toxin is best known to clinicians as a deadly poison produced by the Clostridium botulinum bacterium. Only within the past 2 decades have clinical applications for this toxin surfaced. Originally, applicability was found for botulinum toxin in the treatment of strabismus; however, this single indication has now grown into many. Currently, the Food and Drug Administration (FDA) has approved botulinum toxin A for blepharospasm, strabismus, cervical dystonia, and the aesthetic improvement of glabellar rhytides.

Common clinical uses

Currently, botulinum toxin is most commonly used in the management of expression lines.. These lines often caused patients to be misinterpreted as angry, anxious, fearful, or fatigued. In the past, facial plastic surgeons only had surgical options including excision or implantation of fat, collagen, or silicone. These procedures often provided minimal improvement and exposed patients to the risks associated with surgery. Injections of botulinum toxin A (Botox or Dysport) provide an opportunity to manage these Expression lines with minimal morbidity. The 3 most common sites for injection are the glabella (frown lines), periorbital crow's feet, and forehead areas.

Pathophysiology

Etiology of Expression lines

Expression lines result from the contraction of the underlying facial musculature. The forehead is a complex of muscles called the frontalis. The frontalis muscle, responsible for the surprised appearance when acting unopposed, mediates elevation of the brow and is primarily responsible for horizontal wrinkles. Soft tissue laxity of the forehead and periorbital area causes brow ptosis and reflex contraction of the frontalis muscle to restore brow position, exacerbating forehead rhytides. Treatment of these rhytides with BOTOX® can increase brow ptosis.

The frontalis muscle can also be responsible for the appearance of scowling. However, the main agent responsible for the appearance of scowling is the corrugator muscle. The normal function of the corrugator is as a brow adductor, bringing the eyebrow medial and inferior. Chronic contraction of the corrugator results in deep vertical hyperfunctional lines between the eyes, sometimes referred to as a glabellar crease. The depressor supercilii muscle pulls the medial brow inferior and medially. The last muscle in this group is the procerus muscle, which overlies the nasal root. Contraction of the procerus results in a snout-nose appearance and a horizontal rhytid at the nasal root.

Pharmacology

The Clostridium botulinum bacterium produces many distinct toxins lettered A through G.  However, toxin A is most familiar to Doctors. Botulinum toxin A (BOTOX® or Dysport) causes paralysis of the muscle. This is accomplished in 3 steps preventing certain neurotoxins from stimulating and therefore contracting the muscle.

The toxin requires 1-5 days to take effect, reflecting the time necessary to disrupt the neurotoxin delivery.

The effect of botulinum toxin lasts 8-12 weeks.

Indications

Current indications for BOTOX® or Dysport injections include the following and other medical conditions not mentioned here:

• Expression lines (eg, glabellar, forehead, crow's feet, platysma, nasolabial lines)
• Hemifacial spasm
• Post–Bell palsy synkinesis
• Blepharospasm
• Spasmodic dysphonia
• Strabismus
• Cervical dystonia
• Hyperhidrosis - excessive sweating
• Migraines

Contraindications

Contraindications to BOTOX® or Dysport injections include the following:

• Pregnancy
• Lactation
• History of reaction to toxin or albumin
• Preexisting motor neuron disease (eg, myasthenia gravis, Eaton-Lambert syndrome, neuropathies)
• Age younger than 12 years
• Infection at the injection site
• Coincident administration of aminoglycosides can potentiate paralysis (relative contraindication)

Treatment

Before the procedure is undertaken, a thorough history (including prior facial surgical procedures) and medication review are undertaken. Attention is focused on looking for those patients with contraindications as previously discussed.  A close-up photograph that isolates the area of interest should be taken, as well as a full-face photograph. Photographs are taken at rest and during muscle contraction if necessary.

Physical examination concentrates on the identification of prior facial surgical sites, the assessment of the thickness of the skin, and the quality of the skin. Higher doses of Botox or Dysport is needed in thicker skinned patients, patients with larger muscles, and men.

Botulinum toxin A (BOTOX®) arrives on dry ice and must be stored frozen at temperatures lower than -4°C. It comes in a 100-U bottle. One unit is defined as the median lethal dose in mice. The median lethal dose in humans is estimated at 3000 U. The toxin generally is mixed with 2.5 mL of 0.9% nonpreserved sterile saline solution, creating a concentration of 40U/mL.

The area of injection can be covered with topical anesthetic cream (eg, eutectic mix of local anesthetics [EMLA]) or can be anesthetized using ice. The solution then lasts up to 4 hours if refrigerated between injections, according to the manufacturer. Hexsel et al conducted a blinded multi-institution study and demonstrated that reconstituted BOTOX® retained its efficacy for up to 6 weeks when stored at 4°C.

• Forehead
  • A total of 10-30 U should be sufficient for this area. The patient is instructed to contract the areas of concern to demonstrate the approximate location of the expression muscle. The injections are divided into 2- to 4-U injections.
• Glabellar region - Frown Lines
  • A total of 15-20 U should be sufficient for the frown lines.
• Periorbital crow's feet: A total of 12 U is used per side. Injections are divided into 3 U each. The BOTOX® must be placed outside the orbital rim to avoid intraorbital complications.
• Nasolabial: This area has been difficult to inject and offers mixed results.  Injection of 2-3 U to paralyze the muscle is used.
• Platysma - Neck bands : Platysmal bands can be treated with the direct injection of botulinum toxin into the concerning band. Once the band is identified, 5 U can be injected per band.

Reinjection

If a patient feels that little benefit was derived from the original injection, reinjection can be performed 1 week postinjection. However, 2-3 weeks postinjection is probably a more practical time for a return clinic visit. Generally, 2.5-5 U are used for reinjection. Reinjection strategies are still evolving. Once the patient has a satisfactory result, the next visit is at 2-3 months or when the patient requests another treatment.

Complications

The most feared complication is temporary paralysis of nearby facial musculature. Approximately 1-3% of patients may experience a temporary upper lid or brow ptosis (dropping); the most troublesome complication to the patient is upper lid ptosis.  The ptosis usually lasts 2-6 weeks. Treatments are available if ptosis does occur.  At NewSkin Laser Center, over 10,000 injections and being a platinum member of Allergan by using large volume of BOTOX®, we have not had a case of ptosis yet.

Bruising can occur, particularly if a small vein is lacerated or a patient is taking aspirin, vitamin E, or NSAIDs. Ideally, patients should stop taking these products 2 weeks before the procedure. Headaches can occur after BOTOX® injections;  To date, no significant long-term hazards of botulinum toxin injections have been identified in excess of placebo groups.

Future

The popularity of BOTOX® is unmatched in cosmetic surgery. The use and scope of botulinum toxin increases every year. Patients have shown a high degree of satisfaction with the procedure. Current research focuses on using BOTOX® as an adjunct to a myriad of surgical and ablative procedures.

Botulinum toxin A now has been used in significant numbers for 20 years. Its injection has proved to be an extremely safe strategy for selectively inducing muscle paralysis.