Medical Rhinoplasty

Multi-mini Botulinum Toxin

The technique of precision placement of multiple minidose injections of botulinum toxin (BTX) i.e., more injections, each of a much lower dose, has been described as multi-mini BTX (M-M BTX). In M-M BTX, the target muscles are carefully observed and palpated; the points of maximum movement are identified and injected. Compared with standard BTX protocols advocated by manufacturers, M-M BTX has the advantages of being more controlled and predictable in its action, more natural in its effects, more economical in the quantities of BTX used, and possibly marginally longer in its duration of action (patients are typically booked for their next treatment 5.5 months after the last one).

Nasal Muscle Function and Anatomy

The muscles of the nose serve to open and close the nostrils, also known as the nares. Hence, there are dilator muscles and constrictor muscles. The main function of the dilators is to ensure that the nostrils do not become sucked flat on inspiration, especially on deep inspiration. Indeed, the commencement of deep inspiration is immediately preceded by dilation of the nostrils. The dilators are more developed in certain ethnic groups, and this is apparent as flared nostrils and/or arched nasal side walls. In all races and ethnic groups, flaring of the nostrils is a manifestation of anger.

The function of the contractor muscles is less clear, but it has been noted that some free divers can teach themselves to close their nares when submerged. Presumably, the increased external barometric pressure of the deep water assists with this.

The surface anatomy of the nose is outlined in Fig. 21.2 . The principal nostril dilators and nasal tip depressors are listed in Box 21.1 .