Opthalmology

Question 1

Describe the basic histologic composition of the conjunctiva

Answer 1

The conjunctiva is composed of nonkeratinized, stratified, squamous epithelium with intermingled goblet cells. Subjacent to the epithelium is the lamina propria (Tenon’s capsule)

Question 2

The conjunctiva has two surgical planes. Describe them and give a clinical example when each would be used.

Answer 2

1) Plane between the conjunctival epithelium and the Tenon’s capsule - used for harvesting conjunctive grafts/flaps
2) Plane between the Tenon’s capsule and the bulbar sclera - used for tumor excision and transconjunctival enucleation

Question 3

You are performing a conjunctival patch to address a deep corneal ulcer
Name three forceps appropriate for conjunctival manipulation
What suture size, type and needle would you utilize?
What precautions would you take concerning suture knots, suture, tags, and suture pattern?

Answer 3

Forceps (fine-toothed): Colibri, Castroviejo or fine-toothed Bishop-Harmon
Suture: 5-0 to 7-0 Polyglactin or Polyglycolic Acid (Vicryl), swaged-on reverse cutting or taper point needle
Favor a continuous pattern to minimize the number of knots. Bury knots, or strategically placed them to avoid contact with the cornea. Cut tabs very short.

Question 4

Define dermoid Vs coloboma

Answer 4

Dermoid: Benign congenital mass of ectodermal or mesodermal origin. Usually located on the lateral limbal region of the cornea, containing cutaneous, epithelium and hair.

Coloboma: refers to the congenital absence of part of an anatomical structure. Most commonly observed in the eyelid, lens, macula, or optic nerve.