Practitioners > Case Studies & Posters > ROSE K Post Graft - Wow!

ROSE K Post Graft - Wow!

History:

Patient is female, 25 years old and was referred to our clinic (Dec 2008) with the following noteworthy history and findings:

  • Myope since childhood
  • Had her LASIK surgery done BE - 2003
  • Post LASIK infection RE leading to a need for keratoplasty
  • Penetrating keratoplasty done RE-2004
  • Patient developed cataract in RE and was operated along with IOL implantation RE-2003

On Examination:

Unaided eye vision RE = 6/60  LE =6/12
Best corrected visual acuity with glasses: RE -3.00Dcyl x 20 6/18  LE -1.25DSph 6/6p
 
RE shows obvious 360 degree surgical scar of keratoplasty with healthy graft.
 
Keratometry:  (Ref index of 1.332 CZ)
(irregular mires + in all meridians)
     RE  52.0 @ 130           LE  45.0 @ 40
↔  RE  6.38mm @ 130      LE  7.38mm @ 40
 
While LE was fitted with regular RGP lens and VA of 6/9 (clear) was achieved, RE did not tolerate regular RGP.  The lens on RE was unstable, poorly tolerated and with marginal visual reward.
 

For OD:

Patient was explained about Rose K Post Graft lens and she consented to try.

The trial lens tried was:

BC 6.60 (calculated empirically as 0.3mm steeper than average K). This was too flat.

Thus the final selected trial lens was:

  • BC = 6.40
  • DIA = 10.4
  • Power = -15.5
  • Edge Standard
  • Over refraction:  +6.00D
  • VA = 6/6p 

Fluorescein pattern was practically parallel with good centration, stable vision and good subjective comfort.

We prescribed:

  • RE
  • BC = 6.40
  • DIA = 10.4
  • Power = -9.00
  • Edge Standard
  • Boston XO
  • Ultraviolet protected
  • Rose K Post Graft,
  • Violet

VA on the dispensing visit OD = 6/6p, Fluoroscein fit good and ame as in trial fitting.  Vision was stable and patient was very happy on achieving good vision in RE again.

Discussion:

A)  The Rose K Post Graft lens performed better than regular RGP due to:

  1. Larger diameter
  2. Better optics
  3. Reverse geometry
  4. Better edge design
  5. Perfect repeatability of design as in trail lens

b)  The power was calculated by adding the vertexed over-refraction to trial lens power.

c)  Boston XO material was chosen because of the high Dk value (in order to provide near-natural oxygen flux through the lens to this already 'eventful' cornea).

D)  Fluoroscein pattern through this Ultrviolet protected lens could be seen through the Wratten filter (Kodak filter #12)

E)  Violet colour was chosen because our clinic fits Rose K2 lenses in blue.  Just looking at violet colour in future (even before seeing patient data sheet) will give us an indication that this is Rose K PG lens.

In all, this was a very gratifying experience and a 'win-win' situation for manufacturer, dispenser and the patient.

 
Rajesh Wadhwa
Optometrist, New Delhi, India
M.Optom.
B.Ophth.Tech Hons.(AIIMS)
B.Sc.Hons. (DU),
Fellow of International Assoc. of Contact Lens Educators (Australia),
PG Dip. in Management