Lecture 9 Fitting contact lenses to sleep in

Question 1

What is the new terminology for overnight wear?

Answer 1

planned overnight wear (7 days and 6 nights)

sporadic overnight wear (30 days and nights)

Question 2

What are the physiological considerations?

Answer 2

*Aim high Dk/t to ensure no significant corneal swelling
*Aim for the same as normal overnight swelling of 4%
*Harvett and Bonanno criteria: need to achieve 125 Dk/t
*Need good corneal integrity

Question 3

What are the contraindications for overnight wear?

Answer 3

*Monocular patients- risk to one eye
*Previous issues with corneal oedema
*Evidence of current neovascularisation
*Patients prone to CLIPC (caused by mechanical issues)
*Diabetics- corneas recover slower
*Evidence of poor compliance

Question 4

What are the fitting considerations?

Answer 4

*Adequate tear exchange
*Preference for loose fitting

Question 5

What patients are you likely to fit with overnight wear?

Answer 5

*Patient preference
*Therapeutic reasons (entropion)
*Very young children (Aphakes)
*No facilities for disinfection
*Vocational requirements (shift work)
*Social activities (out in wilderness, no disinfection facilities)

Question 6

What is the fitting approach for existing wearers?

Answer 6

-start with daily wear with the new lens over the first few weeks
-examine the px after the first night of overnight wear
-review again after a period of extended wear (2-4 weeks)
-Review after at least a weeks worth of wear towards the end of the day
-More regular routine aftercare (6 months maximum)

Question 7

What is the fitting approach for new wearers?

Answer 7

-develop successful daily wear first
-need to have a history of compliance
-same process for existing wear
-earlier recalls

Question 8

What complications can you get?

Answer 8

Mechanical issues
Metabolic issues
Infection (5x more risk than daily wear)