Normal Size Eye with Light Perception
(A True Scleral Prosthesis)
This case presents a rare congenital aberration (Sturge-Weber
Syndrome) which consists of benign tumors seen in the manner
of heavily dilated and newly formed blood vessels.
As shown, it usually occurs unilaterally, and in this case
involved half the face and all of the bulbar conjunctival
tissue in the affected eye. Beyond this noticeable
deficiency, the light perceptive eye had a normal clear cornea
and a deep anterior chamber, but when comparing the blue
pigmentation in the iris in normal room lighting, its pupil
remained constricted, which allowed its stroma to show more
vibrant lighter striations. This condition is called
anisocoria, where the pupils are not of equal size.
Imbalance in iris color would only be detectable when the
normal eye's pupil becomes dilated, which causes its stroma
pigments to appear darker in color tones.
Inasmuch as the main concern was to detract from the abnormal
inflammation of the conjunctiva, it was elected to produce
what can be described as a (true) scleral cover shell prosthesis,
or more appropriately called a 'donut' scleral shell prosthesis
since the corneal portion of the shell is not required.
This would also eliminate any chance of causing corneal ulceration
were the prosthesis to be worn over an extended period of
time that included sleeping. A Phase I clear acrylic
moulded trial shell was fitted over the sclera and checked
for blanching (pressure points) and displacement during normal
eye excursion. Any nonconforming areas would quickly
be seen as white sclera and any displacement of the shell
would rub against the cornea. The Phase II 'true' scleral
shell duplicated the trial shell in white acrylic and only
required a limited amount of red threads and tinting to duplicate
the sclera and vascular pattern of the normal eye.
Sturge-Weber Syndrome affecting the skin and conjunctival
tissue of the eyeball.
The completed (True) scleral prosthesis in position covers
most of the affected conjunctival tissue without compromising
normal eye movement.
The impression moulded scleral prosthesis is similar in design
to that of the empirically fit clear acrylic 'donut' shaped
conformers worn post-operatively after removal of (symblepharon)
adhesions between the eyelids and eyeball.