Orbital Fat (Adipose Tissue) and the Advantage of Youth

If there were advantages to losing an eye at an early age one would highlight the child's ability to adapt to monocular vision more readily than an adult's sudden loss of vision and reconciling with the loss of depth perception.  Another advantage would be from the position of cosmesis.  When a child loses an eye, the orbital (adipose) fatty tissue that cushions the eyeball remains fairly firm and will remain in its orbital position for many years following removal of the eye.  Whereas, the adult can experience partial loss of a less firm adipose tissue at the time of evisceration or enucleation, or in later years due to absorption of the orbital fat or gravitational displacement.  This can occur despite placement of a large orbital implant.  Retention of this orbital soft tissue is most important for facial (cosmetic) symmetry as it relates specifically to the upper eyelid.

This first case, despite being a traumatic (perforated globe) injury shows the superior sulcus (the area between the eyebrow and the lid margin) to remain symmetrically balanced over a 27 year period.  This was also significant since the Iowa motility implant inserted with its rectus muscles imbricated over the implant (overlapped and sewn together) at the time of surgery, rotated 90 degrees within the first month and gave the eye socket the appearance of a ball implant.  (Note: The Iowa implant's anterior surface had four well pronounced nubbins that would offer an irregular contour for the posterior surface of the prosthesis to conform to.  This would normally transfer excellent movement to the prosthesis.)

Figure 16A This photo was taken immediately after the first prosthesis was first fitted. Age 2½ years.

Figure 16B As a first year college student there is still no anatomical change in the adipose tissue in the superior sulcus.  Age 17 years.

Figure 16C As a young career woman at the age of 29 years the only changes required over the years were replacement prostheses as the skull and bony orbital wall enlarged.