CCA Ocular Prosthetics 3 — Questions and Answers
Question 1: What is the recommended cleaning frequency for an ocular prosthesis?
- Daily removal and cleaning
- Cleaning every 3–6 months by the anaplastologist, with daily socket hygiene by the patient (Correct answer)
- Annual professional cleaning only
- Cleaning only when discharge is visible
Correct answer: Cleaning every 3–6 months by the anaplastologist, with daily socket hygiene by the patient
The standard recommendation is professional cleaning and polishing every 3–6 months, while patients maintain daily socket hygiene without necessarily removing the prosthesis each day.
Question 2: A patient's ocular prosthesis has developed a rough posterior surface. What is the most likely clinical consequence?
- Improved retention
- Increased discharge and conjunctival irritation (Correct answer)
- Reduced orbital volume
- Better corneal reflex alignment
Correct answer: Increased discharge and conjunctival irritation
A rough posterior surface creates friction against the conjunctiva, causing irritation, increased mucous discharge, and potential socket inflammation.
Question 3: In ocular prosthetics, what does the term 'enophthalmos' describe in the context of an anophthalmic socket?
- Protrusion of the prosthesis beyond the orbital rim
- A sunken appearance of the prosthesis due to insufficient orbital volume (Correct answer)
- Infection of the orbital socket
- Extrusion of the orbital implant
Correct answer: A sunken appearance of the prosthesis due to insufficient orbital volume
Enophthalmos in an anophthalmic patient refers to the sunken, recessed appearance caused by inadequate posterior orbital volume support.
Question 4: Which material is most commonly used for fabricating custom ocular prostheses today?
- Vulcanite rubber
- Polymethyl methacrylate (PMMA) acrylic (Correct answer)
- Silicone elastomer
- Porcelain
Correct answer: Polymethyl methacrylate (PMMA) acrylic
Polymethyl methacrylate (PMMA) acrylic is the standard material for custom ocular prostheses due to its biocompatibility, durability, and excellent optical properties.
Question 5: What is the primary purpose of a peg or post in a motility-coupled ocular prosthesis?
- To increase prosthetic weight for better retention
- To mechanically couple the prosthesis to the orbital implant, transmitting implant movement to the prosthesis (Correct answer)
- To provide a mounting point for cosmetic eyelashes
- To anchor the prosthesis to the orbital rim
Correct answer: To mechanically couple the prosthesis to the orbital implant, transmitting implant movement to the prosthesis
A peg or post drilled into a motility implant creates a mechanical link that transfers implant movement to the overlying prosthesis, improving motility.
Question 6: When determining iris position for a custom ocular prosthesis, the primary reference point is:
- The nasal bridge midline
- The pupil position of the contralateral eye in primary gaze (Correct answer)
- The center of the orbital rim
- The patient's subjective preference
Correct answer: The pupil position of the contralateral eye in primary gaze
The pupil of the contralateral eye in primary gaze serves as the primary reference for placing the iris on the prosthesis to achieve symmetric appearance.
Question 7: A patient returns with a new ocular prosthesis that appears to have an exotropic alignment. What adjustment should be considered?
- Increase the prosthesis size
- Reposition the iris medially by modifying or remaking the prosthesis (Correct answer)
- Prescribe prism glasses
- Refer for strabismus surgery on the contralateral eye
Correct answer: Reposition the iris medially by modifying or remaking the prosthesis
An exotropic (outward-turned) appearance is corrected by repositioning the iris nasally (medially) on the prosthesis during modification or fabrication.
CCA Ocular Prosthetics 3
What is the recommended cleaning frequency for an ocular prosthesis?