Visual And Refractive Outcome Of Phacoemulsification And Intraocular Lens Implant In A 16-Cut Radial Keratotomy Treated Eye

To report on a successful and satisfactory visual and refractive outcome of a phacoemulsification and intraocular lens implant in an eye that was previously treated with a 16-cut Radial Keratotomy for Myopia.

A 71-year-old patient presented for management of a cataract in his left eye. The patient had radial keratotomy for myopia to both eyes 40 years previously with 8 RK scars on the right cornea and 16 RK scars on the left cornea. Right cataract surgery had been performed elsewhere in 2012.

Best corrected visual acuity was RE CF with glasses and 6/24 pinhole; LE 6/36 with glasses and no increase with pinhole. Pre-op refraction was, RE +6.50 / -6.50 x 36 and LE +4.75 / -4.50 x 34 with BCVA PL.

To calculate the IOL power needed, the biometry values had to be adjusted. The left cornea was very flat with K readings of 27.85 D (12.16mm) and 28.35 D (11.94mm), with a SE of 28.09 D (12.05mm). As the biometry calculation formula would not accept a K reading below 30 D, a value of 30 D was entered and a +2.5 D was added to the IOL selection to achieve a lens calculation for emmetropia.

The best location for the incision was found in between RK scars rather than making a scleral tunnel. Vision blue dye was used, and the fluid settings were adjusted to minimise lens-iris-diaphragm-retropulsion-syndrome (LIDRS) with anterior chamber deepening. A standard monofocal IOL using the HOYA pre-loaded XC1 Vivinex lens was implanted through a 2.2mm incision. All stages of surgery came to a successful and uneventful conclusion. No sutures were required. 

At the 6-week post-op refraction the left eye returned a result of:

6/48-3 unaided  +4.00 / -6.50 x 47 = 6/12^-3

+1.50 add = 0.36 LogMAR at 66cm.

+2.50 add = N8 – N10 at 40cm.

Later, the patient achieved a visual acuity of 6/9⁺¹ with refraction. At 3 months post-operatively he was fitted by his optometrist with an ICD FlexFit Toric semi-scleral CL and achieved 6/7.6^-2 in the left eye.

Managing cataracts with pacoemulsification and intraocular lens implants in a previously treated radial keratotomy eyes has its own challenges. However, with proper biometry calculations and well planned surgery, satisfactory outcomes can be achieved. Additionally, high quality optometric management of the contact lens fitting can enhance the visual potential in those patients.