Regional Veterinary Surgery

SURGICAL CONDITIONS AFFECTING THE CONJUNCTIVA

• Conjunctiva has two parts called palpebral conjunctiva and the bulbar conjuctiva.
• The normal appearance of the conjunctiva is  pink , smooth and moist. 
• In systemic diseases the appearance of conjunctiva is altered in gastrointenstinal disorders it is congested, in jaundice it is yellow, shows petichae (pinpoint heamorrhages) in toxaemia and septicaemic conditions.
• Echymosis of conjunctiva is noticed in protozon diseases like surra. It is dry and pale in shock, pale and watery in anaemia, ulcerated in riboflavin deficiency, and thickened in vitamin A deficiency (Xerophthalmia).

Conjunctivitis

• Inflammation of the conjunctiva is one of the most common eye diseases.

Conjuctivitis - Goat	Conjuctivities and blepheritis in a dog

Etiology

• Bacterial or virus infection, Irritation due to chemical substances, Presence of foreign bodies, Trauma,  Allergy and Nutritional deficiencies.

Sampling for ABST

Classification

• Based on etiology, conjunctivitis may be classified as specific conjunctivitis (e.g., seen in pink eye in horses, distemper in dogs), and non – specific conjunctivitis.
• Clinically conjunctivitis is classified into three types, ciz., acute, subacute and chronic conjunctivitis.
• According to the nature of inflammation the following varieties of conjunctivitis are recoreded.
  • Catarrhal conjunctivitis, e.g., conjunctivitis due to mild bacterial infection or trauma.
  • Purulent (suppurative) conjunctivitis, e.g., conjunctivitis  seen in pink eye of horses, distemper of dogs, etc.
  • Diphtheritic conjunctivitis, e.g., croupous conjunctivitis seen in birds. Diphtheritic conjunctivitis seen in calves due to infection by fusiformis necroforus.
  • Granular or follicular conjunctivitis, causing small follicular enlargements on the conjunctiva known as trachoma.

Symptoms

• Lacrimation: In the beginning stages of conjunctivitis lacrimation is thin and watery. Later it becomes thicker and has a tendency to stick on to the edges of lids and cheek. 
• Photophobia and blepharospasm are not marked in simple conjunctivitis. If these symptoms are present extension of inflammation to the cornea should be suspected.
• Discomfort.
• Chemosis (swollen conjunctiva through the palpebral fissure).

Chemosis
Swollen conjunctiva through the palpebral fissure 

Diagnosis

From the symptoms

• Treatment
  • The conjunctival sac is irrigated at frequent intervals with warm saline solution or a mild antiseptic lotion.
  • The eye lotions commonly used were: ZAB lotion (zinc sulphate ½ %, alum 1%, boric acid 2%), percholride of mercury lotion (1 in 30,000 to 1 in 10,000), argyrol (5%) and boric lotion (2 to 3 %).
  • 5 % povidone Iodine can be used to cleanse the eye, followed by topical antibiotics and NSAIDS if necessary. Always check the integrity of the cornea prior to use of a corticosteroid.
  • “Chloromycetin applicaps” are found effective in many cases of conjunctivitis due to bacterial infection. Other antibiotic eye ointments like “teramycin eye ointment” are also effective.  Hydrocortisone eye ointments are indicated in allergic conjunctivitis.
• Epiphora
  •  Epiphora is a symptom characterized by excessive flow of tears. It may be due to conjunctivitis, or due to stricture, atresia or obstruction of the lacrimal passages. If due to conjunctivitis it passes off when the inflammation subsides. Irrigation of the lacrimal passage or exploration with a flexible probe is necessary if the condition is due to obstruction or atresia. Flouorecin passage time can be studied.

Epiphora
Excessive flow of tears

• Symblepharon
  • Symblepharon is a condition wherein the bulbar conjunctiva is adherent to the palpebral conjunctiva. This may be congenital or may result from blepharitis.
• Ankyloblepharon
  • It is adhesion of the upper and lower eyelids.
• Pterygium
  • Pterygium is a condition where there is growth of conjunctiva extending towards the cornea.
  •  
  • Dermoid (Dermoid cyst; Treatoma)
  • Dermoid is a misplaced embryonic cutaneous tissue. It is sometimes seen in the eye. Dermoid cyst usually contains hairs growing on it and causes irritation of the conjunctiva and cornea. There is lacrimation. 
• Treatment
  • Large sized dermoids may be removed surgically.
  • Simple excision of the tissue is usally performed.
  • If there is corneal involvement, superficial keratectomy is performed.

Neoplasms of the third eyelid very rare- adenomas, adenocarcinomas and squamous cell carcinomas are reported

Conjuctival tumour	Thrid eyelid neoplasms