What is the Nasolabial Fold?


The nasolabial fold is a naturally occurring line that extends from the corner of the nose to the corner of the lips. The nasolabial word is derived from the Latin for the nose (nasus) and the Latin for the lip (labium), hence the nasus-labium or nasolabial fold.

The nasolabial fold is also called the “parenthesis line” because it looks like a parenthesis that frames the upper lip. Other names for the nasolabial folds include the “laugh lines” and “smile lines.” The nasolabial folds separate the cheeks from the upper lip.

What is the anatomy of nasolabial fold? Dr. Fritz Barton at UT Southwestern showed that there are dermal extensions or attachments from the skin under the nasolabial fold to the underlying facial muscles. Dr. Anthony Pogrel at NYU revealed that there a two muscle bundles under each nasolabial fold. The more superficial muscle runs parallel to the nasolabial fold. The deeper muscle runs perpendicular to the nasolabial fold. Dr. Pogrel further showed that the cheek or malar fat is held in place by internal support structures within the cheek fat. Dr. Pogrel also discovered that the cheek fat is held in place by the muscles in the nasolabial fold.

Anatomically, why do the nasolabial folds get worse as we age? The deepening of the nasolabial fold is a two-part process. First, the nasolabial fold or trough gets deeper because there is a loss of fat at the bottom or base of the nasolabial fold. As we age, we lose fat in the face. Facial fat loss causes the face to become more skeletonized. Second, the upper wall around the nasolabial fold gets higher. As we age, facial collagen decreases. Collagen is a supporting structure in the face. The cheek drops because there is a loss of collagen. As the cheek drops, the cheek fat runs into the nasolabial fold, gets hung up, and tries to ride over the nasolabial fold. This action is like a wave in slow motion. As the cheeks drop, more and more fat accumulates on the upper border of the nasolabial fold. The result is a high wall of cheek fat piling up above an ever-deepening nasolabial fold. Both these unfortunate events serve to deepen the nasolabial fold.

What causes the nasolabial folds to get worse? How can I prevent my nasolabial folds from getting deeper? Even though the accentuation of the nasolabial fold occurs naturally, there are several conditions which can accelerate the presence and depth of the nasolabial fold. The sun causes immense radiation damage to your skin. If there is too much radiation damage to the skin, the skin reacts by actually burning; this is what we call a "sunburn." If the radiation damage is constant or prolonged, the skin's reaction to all this radiation is to protect itself by making a protective layer of a pigment called melanin. Melanin darkens the skin and mildly protects the skin from further radiation damage. Skin producing melanin is what we call a "suntan." Also, not only is the sun’s UV radiation a known carcinogen, but the sun’s radiation also causes direct damage to our skin’s DNA. If there is too much DNA damage, the skin cannot repair itself. The skin’s inability to correct itself, can lead to loss of skin support and thus, skin sag. Sagging cheek skin causes the nasolabial fold to deepen. Smoking also prematurely ages the facial skin. Cigarette smoke has thousands of known chemical carcinogens. Your facial skin tries to protect itself from these chemical carcinogens by reducing blood flow to the areas exposed to cigarette smoke. Decreased blood flow causes a decreased delivery of oxygen. Nicotine causes blood vessels to constrict and further reduces the flow of oxygen. In addition to reduced oxygen in your skin, smoking causes MMP-1 to be stimulated. MMP-1 is a protein which causes collagen to break down. Smoking also causes disruption of the elastic fibers of the face, direct thermal damage to the skin, and reduction in Vitamin A which is a potent skin moisturizer. Massive weight loss can also cause profound deepening of the nasolabial fold. Deepening of the nasolabial fold is due to the significant loss of facial fat. With most weight loss, usually, comes some degree of facial fat loss. With extreme weight loss, loss of fat in the face becomes more extreme. Other factors affect the nasolabial folds. However, these factors are not as easy to control. Smiling or laughing a lot can cause deepening of the nasolabial fold. However, I would not suggest enjoying life less, just so your nasolabial folds look better! Genetics also influence the appearance of the nasolabial fold. If you want to glimpse into the future of your face, just look at your parent’s face. However, at the time of this printing, even though you can change your parents, you cannot change your DNA. Gravity also influences the appearance of the nasolabial folds. However, I do not suggest living in “zero gravity,” just to minimize your nasolabial folds!

How can I get rid of the nasolabial fold? There are four approaches to the treatment of the nasolabial fold. The first approach is to fill the nasolabial fold. There are many different types of fillers. The most common off-the-shelf fillers include Restylane® or Juvederm®. The most common natural filler is your fat. Typically, under local anesthesia, your fat is harvested from your abdomen. The fat is purified and injected into the nasolabial folds. Whether it is off-the-shelf fillers or autologous fat transfer, by filling the base or trench of the nasolabial fold, the depth of the nasolabial fold is decreased. The problem with this approach is that it is usually temporary. The second method to minimize or eliminate the nasolabial fold is the placement of a cheek implant. Cheek implants can be inserted through an incision in the upper gum line. Cheek implants plump up the cheek and drag facial skin upward and backward. Cheek or malar implants help to blunt and smooth the nasolabial folds. The third way to correct the nasolabial fold is direct excision of the nasolabial folds. This procedure is highly successful; however, the surgery does leave a permanent facial scar. The fourth approach is to disrupt or disinsert the attachments of the skin at the base or bottom of the nasolabial fold to the underlying facial muscles. This method is achieved with a facelift. During a facelift, an incision is made just in front of the ear. Dissection is done to the nasolabial folds, and the underlying attachments of the nasolabial folds are undermined. With the nasolabial fold attachments freed, the cheek can be swept upward and backward with permanent sutures. The facelift is usually the best and most permanent treatment of the nasolabial folds. If you are concerned about the appearance of your “parentheses lines,” “laugh lines,” or “smile lines,” please contact Dr. Katzen today to see what he can do to help. Dr. Katzen has multiple offices in Beverly Hills, Las Vegas, and Henderson. Call (310) 859-7770 today to schedule a FREE complimentary consultation to determine what can be done for your nasolabial folds.

* All information subject to change. Images may contain models. Individual results are not guaranteed and may vary.