Looked at in a three-quarter view, a half face can be divided into three parts of equal width by the drawing of two parallel vertical lines. The first line is drawn through the pupil and the angle of the mouth; where this line crosses the jawline, there is a firm tether called the mandibular retaining ligament. The second vertical line is drawn halfway between the first line and the tragus (the little bump in front of your ear hole). These two lines divide a half face into medial, middle and lateral compartments. The medial third is anchored by nose, chin and mandibular retaining ligament. The lateral third is anchored by a complex system of other ligaments. The middle third is largely unanchored and has more fat in it than do the other two thirds.

In youth, the middle third provides the swell (anterior projection) of a beautiful and full young cheek. In older age, the middle third suffers from gravity and drifts inexorably downwards, like a slowly melting half pound of butter, in due course eventuating in a jowl.

To have an idea of how your face will age, everybody knows that putting a mirror on a table and then looking down into it will give you a glimpse of your ghastly future. Most striking is the drifting forwards of the jowl and lower cheek. Because the mandibular retaining ligament is strong and durable (even in older people), it continues to pin the anterior third in its rightful place such that the middle third not only drifts forwards but, in older people, it begins to envelop the jaw line of the anterior third.

In youth, the jawline of the gravitationally doomed middle third is held back towards the ear by the subaponeurotic muscular system (the SMAS layer). Most face lift surgery works by opening the skin in front of the ear in order to put a tuck in SMAS, thereby pulling the middle third back towards the ear. The great news is that a similar effect can be achieved by tightening the SMAS by speckling it with a pattern of high intensity focussed ultrasound (HIFU) dots. These HIFU dots cause microdots of inflammation within the SMAS layer which lead to creation of new collagen within the SMAS and a  consequent tightening of the SMAS and, you guessed it, a welcome drawing up and back of the jowl. All this without a scalpel or an injection! It takes just 20 minutes and can be repeated. It can be done twice a year.