What this site is for
This is patient education about a lid that sits low, published by Chongqing West District Hospital, a tertiary general hospital in Jiulongpo District, Chongqing. It is a concern guide rather than a procedure page: it answers why this is happening, whether it needs treatment, and which of several paths applies. The operations themselves, and the anatomy they work on, are explained on the eyelid hub and on Dr. Mao’s own site, and repeating them here would help nobody.
The distinction the site is built on
Four different structures produce a lid that looks droopy: the skin over it, the fat within it, the muscle that lifts it, and the brow above it. They look similar in a mirror and they are treated in ways that have almost nothing in common. Naming which one is present is most of the decision, and mistaking one for another is the harm this site exists to prevent.
What it deliberately does not do
It does not name products or brands, quote prices or dosages, or promise a result. It does not present a cream or a device as an alternative to an operation for a lid that has genuinely dropped. It does not describe surgical technique, because that belongs to the pages that cover the surgery. And it does not treat a lid that has dropped suddenly, or on one side only, as an aesthetic question at any point.
The limits of a website
Nothing here can tell you which of the four causes is present in your own lid. That requires someone to measure where the lid edge sits, how far it travels, where the brow is and what the eye surface is doing — measurements that take minutes in person and cannot be taken from a photograph. Use this site to arrive at an assessment with better questions, and treat any answer you receive here as general information rather than as advice about you.