Week 1.12 RGP Lens Fitting Flashcards
What are some things that suggest a poor fit of RGP lens
Flat fit = blackness in the middle touch
Crossing limbus
Uneven edge clearance
How can you tell if the astigmatism is with the rule or against the rule from the fit of the RGP lens
If its with the rule the top and the bottom will have more fluorescein
If its at the sides then that’s against the rule
If you had to choose would u rather have more edge clearance or less edge clearance
Better to have more edge clearance than less clearance
How do the wear times for RGP differ from SCL
As the lens can be uncomfortable we can get the px to wear them for approx 2-3hours initially, building up an extra 30 mins every day because of this u may see them more regularly. After 1 week then after a month then after 3 months
What’s in an aftercare appointment for RGP lenses
- history and symptoms - why is ur px here any new developments?
- VA, over refraction - record VA before and after any over refraction
- assessment of lenses on the eye (fit, condition of lens) - white light and with Nafl
- lens removal watch ur patient and assessment of anterior eye - slit lamp. TBUT, any Nafl staining
- recommendations, advice - any changes to give?
- issue a specification - of the lenses they are wearing and how long the specification is valid for
What are questions you ask in history and symptoms
RVF
LEE
WT - today? Usually? Note in hours and days of the week
Age of CL
Up to date specs?
Red eye, pain, photophobia
Habits?
- sleep, swim, shower in lenses?
- how often replace the lenses
- Washing hands and maintaining good hygiene?
- case cleaning
Is px happy with lenses?
How is VA
How is comfort?
Dryness?
Eyedrops?
What solution? How often replaced, age?
VDU use
Smoker?
Any OH, med, allergies, GH
VA and over refraction
Do this before the fit of the lens
As assessing fit u might dazzle/bleach the px retina reducing their VA
Record VA for both eyes before over refraction
Make sure to check near VA also
Record DVA and NVA after conducting over refraction
Record binocular VA too
Comment on visual stability in both eyes also
What to look for in white light assessment
Lens centration
Corneal coverage
Limbus crossing present
Movement on blink
Lens condition - wettability and deposits
Lid interaction/lack of
No lag measure and no push up test
What do we look for in fluorescein assessment for RGP lens
Edge lift
Nafl pattern
Any lens damage seen -n wettability and deposits
Significant Nafl patterns - lack of Nafl underneath lens/air bubbles, dimple veiling (indentations), 3+9 staining
After the fluorescein assessment of RGP lenses what’s next
Anterior eye assessment
Fluorescein in and check tear prism, TBUT and corneal staining
Lid eversion with Nafl to ashes the palpebral conjunctiva - roughness and redness
After the fluorescein assessment of RGP lenses what’s next
Anterior eye assessment
Fluorescein in and check tear prism, TBUT and corneal staining
Lid eversion with Nafl to ashes the palpebral conjunctiva - roughness and redness
What are some general things to note in anterior eye assessment
Lids and lashes - bleph? MGD? Lumps discolouration swelling
Conjunctiva - redness, chemosis
Limbus - neovascularisation? Hyperaemia?
What are some significant complications with RGP lenses?
1) 3+9 o’clock staining - lens is small on cornea and has some thickness to it. There’s a gap between the surface of the cornea and surface of the lens so more tears required to fill that space so can cause dryness and irritation
2) pinguecula & pterygium - yellow degeneration bump on conjunctiva and get this with dry eye and UV damage. If 3 and 9 o’clock staining has not yet been manages you get this. If not managed further and in a sunny and hot country with dry lenses u might get pingecula where conj looks like its growing onto cornea
3) corneal dellen - corneal thinning, years and years of 3 and 9 o clock staining without management
4) dimple veiling - impression of trapped air bubbles. Gaps will fill with fluorescein
What do you address at the end of the aftercare
Px happy with the cost?
Do they need a new lens?
Change the BOZR or diameter of lens to improve the new fit?
Any compliance issues that need discussing?
Any eye drops?
Px good to continue with lenses and WT?
Book next aftercare and give their specification
Do you need to refit the px with a new lens material or modality?
What kind of lens fit is dimple veiling usually seen in
Steep fitting lens
