Nasolabial fat compartment
- Highlighted area
Quick facts
- Definition
- Superficial subcutaneous fat compartment located just lateral to the nasolabial fold.
- Location
- Between the lower eyelid, above, and the jowl area, below; medial to the medial cheek compartment.
- Plane
- Superficial, above the lip elevator muscles and the deep medial cheek fat.
- In aging
- Tends to hold steady or gain mass and to descend, which accentuates the fold of the groove.
- Relevance in HOF
- Helps explain why volume placed directly on the fold does not always soften the smile lines.
The nasolabial fat compartment is one of the subcutaneous fat compartments of the midface. It sits just lateral to the nasolabial fold (smile lines), separated from neighboring areas by fibrous septa, and it is the tissue that forms the "cheek" folding over the groove. Understanding this compartment helps explain why smile lines deepen with age and why filling the fold is not always the best answer.
Where is the nasolabial compartment?
Facial fat is not a continuous layer: it is divided into compartments with their own boundaries, as described in layers of the face.
| Boundary | Structure |
|---|---|
| Medial | Nasolabial fold and upper lip |
| Lateral | Medial cheek compartment (superficial) |
| Superior | Lower eyelid area, below the orbicularis retaining ligament |
| Inferior | Jowl area, near the marionette line |
| Deep | Lip elevator muscles and deep medial cheek fat |
The boundaries vary between people and are not visible to the naked eye: they are described in dissection studies and with dye injection.
How does it take part in the nasolabial fold?
The fold forms at the transition between the cheek, which is more mobile and has thick fat, and the upper lip, where the skin is more adherent to the muscles. With aging, the nasolabial fat tends to hold steady or even gain mass, while the deep support of the midface decreases and tissues descend. The result is a heavier fold over a more marked groove.
That is why reading the fold does not stop at the fold. Loss of deep volume, laxity, the smile muscles and the retaining ligaments all come into play, as shown in smile lines: what softens them.
Why does it matter in HOF?
- Support before the fold: in many cases, the assessment considers support of the cheekbone and the base of the nose before treating the fold directly, at the professional's discretion.
- Risk of weight: superficial volume over an already heavy compartment can accentuate the projection of the cheek over the groove.
- Smile: the fold deepens when smiling. Excess volume may show in motion.
The procedure for the area is in nasolabial fold filler.
How does it show up in the assessment?
- Rest and smile: depth of the fold and how much the cheek drops over it.
- Profile and three-quarter view: projection of the midface and of the base of the nose.
- Pinch test: thickness of the fat over the fold.
Also called: nasolabial fat, superficial nasolabial compartment, nasolabial fat.
Frequently asked questions
What forms the smile lines (nasolabial fold)?
The nasolabial fold arises at the boundary between the mobile skin of the cheek, with the nasolabial fat on top, and the upper lip area, which is more adherent. Loss of deep support, descent of tissue and the action of the smile muscles accentuate the fold.
Does filling the smile lines solve the nasolabial fat?
No. Filler does not remove fat. In general, the assessment considers the support of the midface and the volume of the fold itself, and excess volume over an already heavy compartment can worsen the look.