Conjunctival Deposits
These can occur in both the conjunctiva and
cornea. Some, like some tumors, lead to pigmented changes in the conjunctiva.
However, their typical appear-ance usually readily distinguishes them from
tumors (Fig. 4.24). The follow-ing conjunctival and corneal deposits and
discolorations may occur:
Adrenochrome deposit (Fig. 4.24h). Prolonged use of epinephrine eyedrops(as in glaucoma therapy)
produces brownish pigmented changes in the infe-rior conjunctival fornix and on
the cornea as a result of epinephrine oxidation products (adrenochrome). This
can simulate a melanocytic conjunctival tumor. Therefore, the physician should
always ascertain whether the patient has a history of prolonged use of
epinephrine eyedrops. No therapy is indi-cated.
Iron deposits (Fig. 4.24i). In women, iron deposits from eye make-up andmascara are
frequently seen to accumulate in the conjunctival sac. No therapy is indicated.
Argyrosis.Prolonged used of silver-containing eyedrops can producebrownish
black silver deposits in the conjunctiva.
Ochronosis (alkaptonuria: an inherited autosomal recessive deficiency of
theenzyme homogentisate 1,2-dioxygenase). Approximately 70% of all patients
with ochronosis exhibit brownish pigmented deposits in the skin of the
eye-lids, conjunctiva, sclera, and limbus of the cornea (Fig. 4.24j). The deposits increase with time.
The disorder cannot be treated in the eye.
Metallic foreign bodies in the conjunctiva.A metallic foreign body that is notremoved immediately
will heal into the conjunctiva, where it will simulate a pigmented change in
the conjunctiva (Fig. 4.24g).
Obtaining a meticulous his-tory (the examiner should always enquire about
ocular trauma) will quickly reveal the cause of the anomaly. The foreign body
can be removed under topi-cal anesthesia.
Jaundice.This will lead to yellowing of the conjunctiva and sclera
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