So say researchers at Stanford University School of Medicine (Palo Alto, Calif.) who recently evaluated the long-term effectiveness and stability of conductive keratoplasty for the correction of low to moderate hyperopia.

Conductive keratoplasty and hyperopia: Study design and methods

The researchers evaluated the refractive outcomes of 16 eyes of nine farsighted subjects who had their vision corrected with CK between 1999 and 2000.

Prior to surgery, the mean spectacle refraction of these patients was +1.45 diopters (D) of hyperopia.

The mean follow-up period for eyes in the study was 73 months (6 years, 1 month).

Conductive keratoplasty and hyperopia: Results

Results of the study included:

• At 23 months after the CK eye surgery, the mean refractive error was +0.295 D (20 percent of the mean refractive error present prior to surgery).
• At 48 months after surgery, the mean refractive error was +1.00 D (69 percent of the mean pre-operative refractive error).
• At the final follow-up visit (a mean of 73 months after surgery), the mean refractive error was +1.394 D (96 percent of the mean refractive error present prior to surgery).

No eye lost more than one line of best corrected visual acuity as a result of the conductive keratoplasty procedure.

Conductive keratoplasty and hyperopia: Conclusions

The researchers concluded that while conductive keratoplasty is safe and effective for the correction of low to moderate hyperopia, a significant regression of farsightedness takes place over time after surgery.

Prospective refractive surgery patients should be counseled that the effects of CK for the correction of farsightedness are not permanent, they said.

SOURCE:  Regression of effect over long-term follow-up of conductive keratoplasty to correct mild to moderate hyperopia. Journal of Cataract & Refractive Surgery. September 2009.

Monovision LASIK and CK: Study design and methods

Researchers in the UK evaluated patient satisfaction with visual outcomes in 287 consecutive patients who opted for a monovision correction with LASIK or CK for their presbyopia correction surgery.

Patients were divided into four groups, based on the type of treatment they received:

• Group One consisted of 36 patients with low myopia who received a monovision correction by having only their dominant eye corrected with LASIK for distance vision. No treatment was applied to the other eye, leaving it mildly nearsighted.
• Group Two consisted of 97 patients with moderate to high myopia who received bilateral LASIK treatment for monovision, with the target of leaving the non-dominant eye mildly nearsighted.
• Group Three consisted of 106 patients with good uncorrected distance vision who were given monovision by having a near vision CK correction applied to their non-dominant eye.
• Group Four consisted of 48 farsighted patients who were given monovision by having both eyes treated with LASIK, with the target of producing low myopia in the non-dominant eye.

Four weeks after surgery, patients were asked to complete a questionnaire that assessed their satisfaction with their surgical monovision correction.

The patients were asked to grade their satisfaction with their vision using one of five scores: 1) Couldn’t be better; 2) Pleased with result; 3) Satisfactory outcome; 4) Had hoped for better; 5) Regret having had it.

Monovision LASIK and CK: Results

Monovision was found to be well-accepted by all treatment groups. The breakdown of scores in each group are as follows:

Group One (unilateral LASIK – mild myopia)

• 44.4 percent – Couldn’t be better
• 44.4 percent – Pleased with result
• 8.3 percent – Satisfactory outcome
• 2.8 percent – Had hoped for better
• 0.0 percent – Regret having had it

Group Two (bilateral LASIK – mild to moderate myopia)

• 45.4 percent – Couldn’t be better
• 35.1 percent – Pleased with result
• 6.2 percent – Satisfactory outcome
• 10.3 percent – Had hoped for better
• 3.1 percent – Regret having had it

Group Three (unilateral CK – good uncorrected distance vision)

• 36.8 percent – Couldn’t be better
• 39.6 percent – Pleased with result
• 9.4 percent – Satisfactory outcome
• 12.3 percent – Had hoped for better
• 1.9 percent – Regret having had it

Group Four (bilateral LASIK – hyperopia)

• 25.0 percent – Couldn’t be better
• 37.5 percent – Pleased with result
• 16.7 percent – Satisfactory outcome
• 16.7 percent – Had hoped for better
• 4.2 percent – Regret having had it

Conclusions

The researchers concluded that people with low myopia who undergo unilateral LASIK to improve their distance vision in their dominant eye had the highest degree of satisfaction with monovision, with 97.1 percent reporting “couldn’t be better,” “pleased with result” or “satisfactory outcome.”

The least satisfied monovision patients were those who were farsighted prior to surgery and received bilateral LASIK with an intentional over-correction of their non-dominant eye to make that eye mildly nearsighted. Still, 79.2 percent of these patients reported a “satisfactory outcome” or better.

The researchers said that a perfect refractive outcome is very important in monovision surgery and that even a minor deviation from the intended target can be a source of patient dissatisfaction.

They also said that proper patient selection and careful pre-operative consultation to make patients fully aware of the limitations of monovision are needed to maximize overall patient satisfaction with the procedure.

SOURCE:  Study: Myopic patients more satisfied with monovision correction than hyperopic patients. Ophthalmology Times. April 1, 2009.