Vmax is a type of HIFU. HIFU stands for High Intensity Focused Ultrasound and is a general name for machines like the Ultraformer, Ulthera and Ultracel.
The precision and reliability of HIFU machines are important to ensure desired results are achieved with minimal side effects.
The reason why some HIFU treatments require multiple treatments is because some operators split the usual full treatment into multiple small treatments. This is usually to make it more comfortable and fuss free, but has little clinical evidence behind their efficacy.
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