Category Archives: Orbit

Hapa

“What are you?” is the question asked of each person in Kip Fulbecks beautiful portrait book “part asian – 100% hapa“. It is a collection of uniformly photographed faces all looking into the camera in frontal gaze.  With my understanding of how we all perceive average as attractive, this book opened a new door for me. These were the faces of my own future generations.

Hapa and their parents are typically well aware that the combination of two very different racial-ethnic gene pools creates a mix that appears quite new and noticeably different from either parent.  As with any big change, there is always a positive as well as a negative aspect to these differences.  Most Hapa probably appreciate by now that other people seem to find them interestingly attractive.  Why is this so? 

It has to do with the mental process by which we all perceive and recognize a face.  A lot of research has gone into facial recognition as well as into understanding what we all consider beautiful, but the bottom line is this:  average faces appear more attractive than faces with more extreme features.  (More on this topic read here and here

In very diverse cities where everone is exposured to a wide spectrum of extreme facial features, the averaged mental template of a face represents one that lies somewhere between an Asian, Caucasian, African American and Hispanic person.  Faces that most resemble this average face are perceived as the most attractive.  Perhaps you might have noticed that there are significantly more Hapa celebrities in the media than there are in the general population of the United States(1.9%).

Being more attractive is certainly a plus.  What could possibly be a minus?

As a physician trained in Ohio and Louisiana, I must admit that I’ve treated few Hapa patients. One patient however stands out in my memory. She was part Vietnamese and part Caucasian, in her late 20’s, and complained of a chronic conjunctivitis that just wouldn’t go away with any kind of eye drops. She said it had started a few years ago and had already seen 3 other eye doctors who couldn’t find a cause. Her face appeared about midway between a German’s and a Vietnamese. She had relatively wide eyes with visible lid creases (double-eyelid). On closer examination at the slit lamp, I found something I’d never seen before. Although her eyelashes were dark and fairly straight like an Asian’s, they seemed slightly longer and exited the skin a little closer to the lid margin. At her lateral canthi on both sides, I found her problem. The most lateral 3-4 eyelashes from her upper lid were growing straight under her lateral lower eyelid, rubbing on her bulbar conjunctiva! This is called trichiasis.

 Hapa Eye Trichiasis1 

The straight lash cilia (eyelashes) of her mother evolved in harmony with the other structures of the flatter featured Asian periorbita.  When made to grow on a wider and more contoured lid and skull structure of a more Caucasian like lateral orbital rim, unanticipated problems might present themselves.  The shape and function of her parents’ eyelids and tissues have benefitted from over 10,000 years of divergent evolution.  For my Hapa patient however, she expressed a random assortment of the features from both of her parents, resulting in intermediate structures that are neither here nor there.  This new configuration is in some ways like a new mutation that has yet to be influenced by the last 10,000 years of evolution.

I believe that her eye problem represents just the tip of the iceberg of a new generation of medical problems about to surface in this next generation of medicine.

What makes Asian eyes look different?

The Asian periocular anatomy is very different from that of a Caucasian or African American on many levels. Firstly, the shape of the orbital bones makes a tremendous impact on the 3D shape and angle of the eyelids. In an Asian, the lateral orbital rim, or the rim of bone that can be felt at the outer corner of the eye, sits on average 3mm more anterior than in Caucasians, and 5mm more anterior than in African Americans (Migliori and Gladstone 1984, Tsai et al 2006). This difference in the skull shape significantly affects the angular corners of Asian eyelids, as explains the more rounded outer corners in Caucasians and African Americans.

Secondly, the fibrous strip of tissue that defines the upper and lower lid margins, called the tarsus, is significantly narrower in the Asian patient (6-8mm) compared to Caucasians and African Americans (10-12mm). The upper edge of tarsus is where fine filamentous attachments link the eyelid skin to the eyelid, and corresponds to the height of the lid crease. It is these attachments that can be weak in Asians who do not have a visible lid crease, often called a “single eyelid” configuration.

Another difference is the additional layer of fatty tissue in the Asian eyelid that is not found in either Caucasians or African Americans. This extra layer of fat helps to separate the eyelid skin from the muscle and tarsus, which is typically firmly attached in Non-Asians. By increasing the thickness of Asian eyelids, this layer may also prevent a lid crease from forming at the upper border of tarsus.