The purpose of this investigation was to evaluate the degree of efficacy of eliminating crow's feet by means of direct injection of botulinum toxin A into orbicularis oculi muscles under direct surgical vision during either blepharoplasty or face lift operations. Eighteen patients were injected with Botox A-14 in each orbicularis oculi muscle. Dilution was obtained by adding 4 ml of preservative-free saline to 100 IU of Botox A. Doses ranged from 15 to 50 IU in each muscle, varying according to the severity of wrinkles and intensity of muscle contraction. In 10 patients (56 percent), the Botox was injected throughout the outer surface of both orbicularis oculi dissected during a face-lift operation. In eight other patients (44 percent), the toxin was injected into the inner surface of both orbicularis oculi exposed during classic blepharoplasty procedures. Most authors have demonstrated that the effect produced by transcutaneous Botox lasts between 4 and 6 months; the paralysis obtained by direct muscular injection was effective for 9 months in 14 patients (78 percent) and 10 months in the other four patients (22 percent). Results were documented by means of preinjection and postinjection photographs, videotapes, and electromyographs. Neither local nor general adverse effects were noted. The improvement obtained in crow's feet was satisfactory to the patient and to us. The use of Botox intraoperatively permitted at the same time not only the treatment of crow's feet by paralysis of orbicularis oculi muscles but also the correction of senile changes in the lids and face by means of either blepharoplasty or face-lift operations.
The botulinum toxin injected into facial mimetic muscles does produce predictable and reversible paralysis. In the 1970s, Scott and colleagues 1,2 used direct muscle injection of botulinum toxin for the treatment of strabismus. In the 1980s, blepharospasm and hemifacial spasm were also treated by toxin injection. 3,4 Botulinum toxin has also been used for amelioration of spasmodic torticollis. 5
There are two factors principally involved in the development of facial wrinkles, the skin and the mimetic muscles. The skin factor is determined by degenerative age changes such as progressive dehydration, loss of elasticity, and decrease of dermal collagen. 6
For many years all procedures were aimed at solving the skin factor. Rhytidectomy, brow lift, dermabrasion, chemical peeling, collagen injection, laser, and dermatologic products have been the most common treatments. 7
The muscular factor is the contraction of the subdermal facial mimetic musculature, which results in folding of the skin. Effective treatment is the flaccid paralysis of the facial mimetic muscles. Recently, studies have demonstrated the efficacy of the transcutaneous muscular injection of Botox in the treatment of mimetic wrinkles by temporary paralysis of facial muscles. 8,9
The purpose of this investigation was to evaluate the degree of efficacy of eliminating crow's feet by means of direct injection of botulinum toxin A into orbicularis oculi muscles under surgical vision during either blepharoplasty or face-lift operations. Two main factors of senile changes of the face, i.e., skin and soft-tissue flaccidity and mimetic wrinkles, are treated simultaneously by means of toxin injection and either face lift or blepharoplasty. A new approach for the use of Botox is described, and four principal objectives are evaluated: (1) beginning of paralysis, (2) duration of paralysis, (3) effectiveness in eliminating crow's feet, and (4) complications.