Discoloration of conjunctiva( ONE OF THE SYMPTOMATIC CONDITIONS OF CONJUNCTIVA) : Normal conjunctiva is a thin transparent structure. In the bulbar region, underlying sclera and a fine network of episcleral and conjunctival vessels can be easily visualized. In the palpebral region and fornices, it looks pinkish because of underlying fibrovascular tissue.
Causes. Conjunctiva may show discoloration in various local and systemic diseases given below:
1. Red discoloration. A bright red homogeneous discoloration suggests
subconjunctival haemorrhage
(Fig. 1).
2. Yellow discoloration. It may occur due to: (i) bile pigments in jaundice, (ii) blood pigments in malaria and yellow fever, (iii) conjunctival fat in elderly
and Negro patients.
3. Greyish discoloration. It may occur due to application of Kajal (surma or soot) and mascara in females.
4. Brownish grey discoloration. It is typically seen in argyrosis, following prolonged application of silver nitrate for treatment of chronic conjunctival
inflammations. The discoloration is most marked in lower fornix.
5. Blue discoloration. It is usually due to ink tattoo from pens or effects of manganese dust. Blue discoloration may also be due to pseudopigmentation
as occurs in patients with blue sclera and scleromalacia perforans.
6. Brown pigmentation. Its common causes can be grouped as under:
(a) Non-melanocytic pigmentation
i. Endogenous pigmentation. It is seen in patients with Addison's disease and
ochronosis.
ii. Exogenous pigmentation. It may follow long term use of adrenaline for glaucoma.
Argyrosis may also present as dark brown pigmentation.
(b) Melanocytic pigmentation
i. Conjunctival epithelial melanosis. It develops in early childhood, and then remains stationary. It is found in 90 percent of the blacks. The pigmented spot freely moves with the movement of conjunctiva. It has got no malignant potential and hence no treatment is required.
ii. Subepithelial melanosis. It may occur as an isolated anomaly of conjunctiva (congenital melanosis oculi Fig. 2) or in association with the ipsilateral hyperpigmentation of the face (oculodermal melanosis or Naevus of Ota).
iii. Pigmented tumours. These can be benign naevi, precancerous melanosis or malignant melanoma.
Causes. Conjunctiva may show discoloration in various local and systemic diseases given below:
1. Red discoloration. A bright red homogeneous discoloration suggests
subconjunctival haemorrhage
(Fig. 1).
 |
| Fig. 1. Subconjunctival haemorrhage. |
2. Yellow discoloration. It may occur due to: (i) bile pigments in jaundice, (ii) blood pigments in malaria and yellow fever, (iii) conjunctival fat in elderly
and Negro patients.
3. Greyish discoloration. It may occur due to application of Kajal (surma or soot) and mascara in females.
4. Brownish grey discoloration. It is typically seen in argyrosis, following prolonged application of silver nitrate for treatment of chronic conjunctival
inflammations. The discoloration is most marked in lower fornix.
5. Blue discoloration. It is usually due to ink tattoo from pens or effects of manganese dust. Blue discoloration may also be due to pseudopigmentation
as occurs in patients with blue sclera and scleromalacia perforans.
6. Brown pigmentation. Its common causes can be grouped as under:
(a) Non-melanocytic pigmentation
i. Endogenous pigmentation. It is seen in patients with Addison's disease and
ochronosis.
ii. Exogenous pigmentation. It may follow long term use of adrenaline for glaucoma.
Argyrosis may also present as dark brown pigmentation.
(b) Melanocytic pigmentation
i. Conjunctival epithelial melanosis. It develops in early childhood, and then remains stationary. It is found in 90 percent of the blacks. The pigmented spot freely moves with the movement of conjunctiva. It has got no malignant potential and hence no treatment is required.
ii. Subepithelial melanosis. It may occur as an isolated anomaly of conjunctiva (congenital melanosis oculi Fig. 2) or in association with the ipsilateral hyperpigmentation of the face (oculodermal melanosis or Naevus of Ota).
 |
| Fig. 2. Conjunctival melanosis. |
iii. Pigmented tumours. These can be benign naevi, precancerous melanosis or malignant melanoma.
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