Case One

Female, J.B., age 16

J.B. is a high school sophomore, who is at the age where she desperately wants to eliminate her glasses. Her mother reports that it is getting difficult to get J.B. to even wear them at all. Her general and ocular health is unremarkable.

Unaided Visual acuity is 20/70 with either eye at distance, while her near VA is 20/20 with either eye.

Slit lamp exam reveals lids, lashes, and tear film are all unremarkable.

Subjective refraction:

• OD +2.00 - 5.75 X 10 20/30++
• OS +1.25 - 5.50 X 175 20/30++

Keratometry:

• OD 45.25/40.75 @ 5
• OS 45.50/41.12 @ 175
  

Lenses Designed:

• OD 8.33/7.67 +2.25/-2.50 9.5 Diam 8.2 OZ 9.8/2nd Curve 12.50/3rd Curve Lent.
• OS 8.26/7.63 +1.50/-3.00 9.5 Diam 8.2 OZ 9.6/2nd Curve 12.50/3rd Curve Lent.

Over refraction was -.25 OU giving 20/25 with either eye. I decided to keep power as is. The lenses moved centered well and the patient was able to achieve a wearing time of 17hours per day.

Case Two

Female, C.M., age 48

C.M. currently wears bitoric PMMA lenses and is in need of new lenses.   She has noticed see can't see as well out of her spectacle prescription, and her contact lens feel like they need to be polished. She is advised of the advantages of upgrading to GPs, and decides to proceed with a refit to an oxygen permeable material.

C.M.'s ocular and general health were unremarkable.

Subjective refraction:

• OD +3.50 -2.50 X 05 20/30=
• OS +4.75 -3.25 X 160 20/30=

Keratometry:

• OD 44.87/42.50 @ 5
• OS 46.00/42.00 @ 160

Slit lamp was unremarkable, and her current lenses seemed to have an appropriate fit, giving her 20/25= for the right eye and 20/30= for the left eye. She was currently not complaining of any presbyopic complications.

First lenses designed were:

• OD 7.99/7.63 +3.87/ +1.62 9.0 DIAM 7.8 OZ 9.6/2nd Curve 11.30/3rd Curve Lent.
• OS 8.08/7.50 +5.50/ +2.50 9.0 DIAM 7.8 OZ 9.8/2nd Curve 11.50/3rd Curve Lent.

C.M. started wearing the new lenses with the same wearing time as her PMMAs. Two weeks later she returned complaining that her spectacles were more blurry than before. Her vision through the contacts were 20/25= OU at distance and 20/30++ at near. Her subjective refraction was now:

• OD +4.50 - 2.25 X 5 20/25
• OS +5.50 - 3.50 X 162 20/25=

and her keratometry readings were also changed:

• OD 44.00/41.62 @180
• OS 44.87/41.75 @160

I tell her I'm going to design new lenses, and we'll call her when they're ready. She comes in to pick up the new lenses, and tells me her glasses are still blurry but the contacts aren't too bad. Her reading is better but her distance could be better. She sees 20/25+ at near and 20/40++ at distance.
     Turns out she switched her lenses and gave herself biocular vision. I measured K's again and found them flattened even more, so I designed her lenses with flatter base curves and adjusted the power to give her monovision, set up for reading with the right eye. She is happy with her contacts seeing 20/25= at distance with the left eye, and 20/25= at near with the right. She is NOT happy that her spectacles prescription has gotten worse, and continues to wear her glasses only in the late p.m. and early a.m.

Case Three

This is one I am currently working on:  A long term PMMA wearing who was refit into spherical GPs ten years ago. Two years ago he was refit with aspheric contacts which improved comfort. I wish to see if I can improve things more as far as wearing time and comfort go in this ASYMPTOMATIC patient.

Current Subjective refraction:

• OD -4.25 20/20
• OS -4.00 20/20

Keratometry:

• OD 42.87 41.87 @ 180
• OS 42.37 41.62 @ 175

My thought is to get him fit with a bitoric, but how do I decide upon the powers to be used, since the use of the sphere and asphere have molded his cornea, resulting is a spherical refraction?

According to an old pair of his glasses his Rx was at one time:

• OD -4.00 - 1.75 X 175
• OS -3.50 - 1.75 X 007

Would it be easier to keep him in an asphere or refit?