COSMETIC BOTOX INJECTION MIMICKING MYASTHENIA GRAVIS

Keeping up appearances: Don't frown upon the effects of botulinum toxin injections in facial muscles

Aesthetic use of low doses of Botulinum toxin (BoNT) injections into the facial muscles has become a leading non-surgical aesthetic treatment worldwide to reduce facial wrinkles, including glabellar lines, forehead lines, and periorbital wrinkles. Within these aesthetic applications, BoNT injections intend to reduce and prevent wrinkles, and the recommended usage of 2 years is often exceeded, which may result in atrophy of the injected muscles. The long-term effects of BoNT injections in the facial muscles and the evidence of diffusion of BoNT to surrounding muscles are obvious pitfalls and challenges for clinical neurophysiologists in differential diagnosing neuromuscular transmission failures. Also, this is further complicated by the risk of developing side effects upon permanent chemical denervation of facial muscles, with less possibility for reinnervation. This review summarizes the known long-term effects of BoNT over time in different facial muscles and the use of objective electrophysiological measures to evaluate these. A better understanding of the long-term effects of BoNT is essential to avoid misdiagnosing other neuromuscular disorders.

Botulinum toxin injections associated with suspected myasthenia gravis: An underappreciated cause of MG-like clinical presentation

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BoNTA can diffuse to several muscles and result in myasthenia gravis symptomatology.

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BoNTA diffusion can result in increased jitter on single-fiber-EMG.

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Patients may not inform their physicians about the previous cosmetic use of BoTNA.

Introduction

The application of botulinum toxin type A (BoNTA) is accelerating, and this includes the uncontrolled cosmetic use of the BoNTA. Diffusion of BoNTA can disturb neuromuscular transmission in several surrounding and distant muscles and result in clinical manifestations similar to myasthenia gravis (MG).

Case presentations

We report two cases of patients referred for neurophysiological evaluation of suspected MG. A 55-year-old female who experienced dysphagia, dysarthria, right-sided ptosis, and neck extensor muscle weakness; and a 46-year-old male who presented with episodic double vision and right-sided ptosis. Both had the history of previous BoNTA use for cosmetic purposes and for the treatment of migraine before the presentation of their symptoms. In both cases examination revealed normal RNS, quite remarkably increased jitter, and signs of denervation and reinnervation in muscles surrounding the injection sites. After extensive neurophysiological evaluations, the primary cause of their symptoms was found to be related to previous BoNTA injections rather than a primary neuromuscular transmission disorder. It could also be concluded that patients do not automatically inform their physicians about cosmetic BoNTA use and they may not be aware of the potential risks associated with BoNTA therapy.

Conclusions

The presented cases illustrate the neurophysiological findings in two patients with suspected MG after the use of BoNTA and emphasize the importance of inquiring about previous BoNTA injections and highlight that it is essential that patients are informed about possible side effects of BoNTA therapy.

Variable ptosis after botulinum toxin type a injection with positive ice test mimicking ocular myasthenia gravis

We describe a patient who received cosmetic botulinum toxin type A injections to the brow and subsequently developed unilateral ptosis that was variable during examination and was transiently improved after the ice pack test. Ptosis gradually resolved spontaneously over approximately 3 months. This is the third patient to have variable ptosis documented after botulinum toxin type A injection to the brow and the second to have a positive ice test. The ice test is not completely specific for myasthenia gravis but may, at times, improve ptosis resulting from other defects at the neuromuscular junction. Wound botulism now is much more common because of illicit drug use, and the ice test also might be positive in this setting.

Managing adverse events associated with botulinum toxin type A: a focus on cosmetic procedures

Botulinum toxin A (BTXA) has become a widely used drug in cosmetic dermatology, not only to treat focal hyperhidrosis but also hyperkinetic facial lines, platysma bands, décolleté bands, and other skin features. The spectrum of possible adverse effects of BTXA is broad but fortunately those that have been observed with cosmetic use of this product are generally mild and transient. The major tools for preventing adverse effects from BTXA are knowledge and skill. Use of correct injection techniques is mandatory since most unwanted effects are caused by incorrect technique. Knowledge of the target structures, e.g. the facial and extrafacial muscles, allows physicians to select the optimal dose, time and technique. The most common adverse effects are pain and hematoma. In the periocular region, lid and brow ptosis are important adverse effects. Adverse effects such as pain, hematoma, ecchymosis, and bruising may also occur in the upper and lower face and at extrafacial sites. Other possible adverse effects seen in other indications that the user of BTXA in cosmetic dermatology should be wary of include induction headaches and possible interaction with concomitant medications. Induction of neutralizing antibodies due to cosmetic BTXA treatment has not been observed. This article also outlines recommendations regarding use of BTXA. Of these, the most important for avoiding most unwanted adverse effects are the proper techniques of dilution, storage, and injection, as well as the careful exclusion of patients with any contraindications. Pain, hematoma, ecchymosis, and bruising can be prevented by cooling the skin before and after BTXA injection. Upper lid ptosis may be partly corrected using apraclonidine or phenylephrine eyedrops. If simple rules relating to the indications for and application of BTXA are followed, this is a safe and effective drug in cosmetic dermatology.