Under-eye treatment in Busan Seomyeon, matched to what is actually there.

More patients arrive here wanting under-eye filler than any other single treatment, and it is right for about a third of them. This page sets out the four options against the four causes so the mismatch is visible before money changes hands.

Cause one — hollowing, treated with filler

A genuine depression in the tear trough where the fat pad has thinned and the ligament tethers skin to bone. Light falls into it and casts a shadow. Under-eye filler is designed for exactly this and produces the most striking results available in the area — placed deep, in very small volumes, with a soft product. The head-tilt test identifies it: if the shadow lightens when you tip your head back, it is hollowing.

Cause two — pigmentation, treated with toning

Melanin in the skin of the lower lid, often genetic and common in Asian and Middle Eastern skin. The area is darker rather than deeper and the colour is brown. Low-energy toning over a course lightens it gradually. Filler here does nothing to the colour and adds volume beneath pigmented skin, which frequently makes it look worse — see dark circles have three causes.

Cause three — thin skin, treated with Rejuran Eye

Skin under the eye is the thinnest on the body, and where it thins further the underlying muscle and vessels show through as a blue-grey cast. Nothing is hollow and nothing is pigmented — the problem is transparency. Rejuran Eye improves dermal density over three sessions, which reduces what shows through. Filler beneath transparent skin scatters light and produces the blue puffiness patients describe.

Cause four — laxity, treated with energy

Crepey texture and fine crinkling from lost elasticity, distinct from all three above. This responds to energy lifting around the orbital area and to skin quality work, not to volume. Adding filler to lax thin skin fills the area without firming it, which reads as heavy rather than rested.

The four tests

Tilt your head back and watch the shadow — if it lightens, hollowing. Stretch the skin gently sideways — if colour remains, pigmentation. Look for a blue-grey rather than brown cast with no depression — transparency. And pinch the skin lightly — if it crinkles and returns slowly, laxity. Most patients over forty have two of the four, which changes the order rather than the diagnosis.

Why does this area produce the most corrections?

Because it combines the highest demand with the smallest margin for error. It is the most requested treatment on the menu, the cause is genuinely ambiguous without an examination, and the tissue punishes both excess volume and superficial placement more than anywhere else. Add that patients arrive naming the treatment rather than describing the problem, and the conditions for a mismatch are all present at once. The corrective work we see is rarely poor technique — it is usually correct technique applied to the wrong diagnosis.

Where does this sit alongside other treatment?

Later than most patients expect. A tired appearance frequently comes from the midface rather than from the lower lid — restoring cheek volume lifts tissue and reduces the shadow indirectly, sometimes enough that no under-eye work is needed at all. Similarly, overall skin quality and tone affect how rested a face reads more than the lid itself does. Treating the under-eye first is common and treating it last is frequently better.

Why does filler go wrong here more than elsewhere?

Because the margin is smallest. The skin is thinnest, the tissue holds water readily, and hyaluronic acid placed too superficially produces the Tyndall effect — a blue cast from light scattering through gel. Too much volume produces persistent puffiness that patients mistake for swelling and wait months to resolve. This area needs less product than any other on the face and receives more.

What if there is a bulge rather than a hollow?

That is fat pad herniation and it is a different problem entirely — surgical rather than injectable. Adding volume beneath a bulge makes the whole area heavier. Distinguishing the bulge above the trough from the hollow below it is part of the examination and it changes the answer completely, including to no treatment at all.

In what order, if I have several?

Pigmentation first, since it takes a course and improves what you are looking at. Skin thickening second if transparency is a component. Volume last, and usually less than initially estimated because the first two changed how the shadow reads. Treating volume first is the standard route to overfilling — see combining treatments.

What if I already have filler I dislike?

It dissolves within a day or two and the area is reassessed a fortnight later. Patients arriving with a puffy blue under-eye from treatment elsewhere are among the more common corrections we see, and it resolves fully. Bring whatever records you have — product and volume if known — see what to bring.