'Crew's feet' are the wrinkles that form with age at the outer corners of the eyes. They are due to contraction of the orbicularis oculi muscles .'Crew's feet' are the wrinkles that form with age at the outer corners of the eyes. They are due to contraction of the orbicularis oculi muscles .The functions of the orbicularis oculi muscle are to close the eye, to drain the tear film, and to create facial expressions. Contraction of this muscle can also drag on the lateral third of the eyebrow, contributing to drooping of the brow with age. In addition, the resting tension of the orbicularis oculi muscle can increase with age and character.
Many patients keep tension at the lateral canthal angle constant, and so have pleasant 'smiling eyes'. This tension can be important to the appearance of the patient: it results in rhytids, but also supports an ageing midface in some patients. It can also prevent the protrusion of age-related lower lid 'bags' (orbital fat) by supporting the orbital septum.
Injections of botulinum toxin will smooth out the rhytids and make the skin look younger, but patients may begin to look 'thin' around their eyes as they lose muscle bulk after repeated injections. They may also look 'drawn' or tired as their mid-face falls over the zygomatic arch. Such changes usually do not become apparent until several treatments have been undertaken. The loss of tension can reverse with time as the orbicularis muscle rarely atrophies permanently;
WHAT TO LOOK FOR WHEN EXAMINING A PATIENT ?
Examine the tone of the orbicularis oculi muscle and the position of rhytids. Are the wrinkles deep? Spread the skin gently between your fingers. Are they still very obvious? If they are, tell patients that they might not notice much effect from the treatment. Advise them about laser resurfacing and skin management .If the wrinkles are mild, advise patients that they might get a permanent effect with time and good skin care.
Examine the facial skin and muscle tone by asking patients to smile while pressing lightly on the zygomatic arch with two fingers.This stops the orbicularis muscle from contracting and so simulates the paralysis of botulinum toxin.
Patients with severe sun damage or poor skin tone (often older patients) will observe that, on smiling, the cheek and orbicularis oculi muscles elevate the facial skin and send it into folds around the lateral orbit. Show patients that this will also happen after botulinum toxin treatment to the crow's feet otherwise they will think that the injections have not worked. It is often wisest not to treat such patients unless they have had surgical or laser correction of skin tone
The Mickey Mouse sign: occasionally patients (especially men over 50 with good skin tone) notice that smiling causes their wrinkles to'bunch up' at the level of the zygoma after treatment of their crow's feet.This can create a curved wrinkle running from the lower orbital rim, out along the inferior border of the orbicularis oculi, over the zygomatic arch, to the top ofthe orbicularis oris (the Mickey Mouse smile).
The periocular fibers have atrophied as planned, but the resting skin tone prevents elevation of the periocular skin and muscle on smiling. The excessive tone of the orbicularis oris, however, associated with thinning of lateral orbicularis oculi fibers, makes the smile appear much wider than the upper face. Take care with such patients .
Examine the contour of the socket
This may also be assessed by the'pencil test. Ask the patient to hold a pencil vertically against the anterior cheekbone. If this passes in front of the cornea , then the patient has good lower lid skeletal support. If the pencil only reaches the lash margin , then the patient is at risk of developing sagging of the lower lid and widening of the palpebral aperture if botulinum toxin is injected for pretarsal orbicularis wrinkles.
Examine the distance between the lash margin and the lower orbital rim, which increases with age. A short distance means that the patient may have botulinum toxin successfully to pretarsal wrinkles without protrusion of orbital fat or folds of skin
Examine the height and width of the zygomatic arch. Does the orbicularis muscle sag between the cheekbone and the eye? Will this area develop a hollow appearance if the muscle becomes thinner? Such a hollowing can be unattractive if accentuated Discuss this and inject more laterally to avoid diffusion to the 'hollow'.
Take especial care over patients with large eyes and wide high cheekbonesThey are also, because of their large eyes, at high risk of sagging of the lower lid. The lower lid normally elevates with smiling as the palpebral aperture narrows and the orbicularis oculi contracts. Botulinum toxin will allow a more wide-eyed smile. This is often attractive, but never when the lateral corner of the lid falls below the medial, creating a pseudo lateral canthus inversus.
Look for a weak orbital septum or protruding orbital fat pads. Ask patients to put their chin down and then to look up into the mirror this will accentuate lower orbital fat pads. If fat protrudes, do not treat the skin under the eyelid as the subsequent loss of tone will cause temporary deterioration of the bags. These patients should have lower lid blepharoplasty and understand that only the wrinkles at the sides of their eyes will benefit from botulinum toxin.
Increased need for tear film: Weakening of the pretarsal orbicularis widens the palpebral aperture .This may aggravate an already compromised tear film by increasing the area requiring lubrication and by reducing the rate of reflex blinking. Such patients may complain of a dry gritty feeling or, more likely, of watery eyes. This is because drying of the eye causes the eyelid to scrape over the cornea and sclera, creating micro-epithelial defects and a sensation of grittiness. The resulting corneal stimulation provokes involuntary epiphora and a watery eye.
Reduction of drainage of tears :Botulinum toxin can be injected into the pretarsal orbicularis to reduce a hypertrophic orbicularis muscle and early 'bagging‘ . However it should never be injected close enough to diffuse towards the lower lid punctum. This would paralyze the lacrimal pump, causinga watery eye unless, luckily, the patient was already suffering from a dry eye.
Temporary paralysis of the lacrimal pump by botulinum toxin can be avoided by staying lateral to the mid-pupillary line, and by using low doses of high concentrations. This treatment is not recommended for the novice practitioner.
Avoid injecting botulinum toxin medial to the outer orbital rim in patients with excessive lower lid skin and fat, as this will cause sagging of the orbicularis muscle with protrusion of the inferior orbital fat. Remember, too, that botulinum toxin will diffuse to different degrees in different patients.
Hooding :Some crow's feet will persist despite botulinum toxin. These include the skin folds at the outer corners of the lids due either to brow ptosis or to sagging of the temporal frontalis muscle or both
wrinkles in motion 0.05 ml x2 each side. wrinkles in motion with lateral depression of brow : as above with 0.025 ml lateral to point of contraction.
wrinkles at rest extending over the zygomatic arch :as above with 0.05 ml one cm inferolateral to lateral canthus. wrinkles at rest with orbicularis hypertrophy and no contraindication :0.0125 ml above and below pretarsal crease, lateral to the mid papillary line. high wide cheekbone: 0.05 ml at outer canthus and 0.05 ml0.5 cm below zygomatic arch.
Bunny lines treatment
Bunny lines are horizontal wrinkles that form across the bridge of the nose. Muscles involved in the development of bunny lines are the transverse portion of the paramedian nasalis muscle (nasalis rhytides) and occasionally the levator labii superioris alaeque nasi muscle (nasoalar rhytides). The transverse portion of the nasalis muscle constricts the nostril and the ala, while the levator labii superioris alaeque nasi muscle contributes to the elevation movement of the upper lip and nasal ala
Repeated Nasal Flare
Some individuals repeatedly and embarrassingly dilate their nostrils in social situations. The sides of the columella/septum become visible when the nostrils are prominently flared. Contraction of the nasalis muscle accentuates the nasal flare. Injection of 5 to IOU of BTX-A bilaterally into the lower nasalis fibers covering the lateral nasal ala, at the most active area of muscle contraction, has produced good results in some patients for 3 to 4 months.
Nasolabial Folds in Selected Patients
The most common treatments for nasolabial folds have been soft tissue fillers and laser resurfacing. Although muscle contraction contributes to the appearance of the folds, injecting BTX-A directly into the area of the fold is not the treatment of choice, because it is likely to result in an symmetric smile, flaccid cheek, flattening of the midface, and incomplete or disappointing results.
The cutaneous upper lip lengthens vertically, as is often seen during aging. However, for some individuals who have a naturally shorter cutaneous upper lip, very small doses of BTX-A (1 U into each lip elevator complex above the nasofacial groove) can be beneficial for improving nasolabial folds, particularly when the injections are given concurrently with other treatment (fillers or resurfacing). Because the duration of effect of this procedure is relatively long (-6 months), it is important to be very careful in patient selection and to be clear about the potential results of the procedure.
