SurgiLight, Inc. Article

ONE-YEAR CLINICAL RESULTS OF 65 CASES LASER PRESBYOPIA REVERSAL (LAPR)

Oscar Mallo, M.D.
Buenos Aires, Argentina

INTRODUCTION
Presbyopia may be caused by many different aging factors including the change of properties in the ciliary and scleral tissues, the change of the elasticity, thickness and shape of the lens and the efficiency of the zonular tension. The existing techniques for the correction of presbyopia include glasses, scleral expansion band (SEB), sclera radial incision and implantation and the use of multifocal IOL. Presbyopia patients may also be treated by a Ho: YAG or conductive keratoplasty for monovision correction. Laser Presbyopia Reversal (LAPR) using sclera ablation was first introduced by Dr. J.T. Lin in 1999 and patented by SurgiLight. The clinical studies for the safety, efficacy and stability of LAPR have been underway in
Buenos Aires, Argentina since September, 2000. This paper summarizes the clinical results of our 65 cases with follow-up of 1–12 months. We shall also discuss some of the findings regarding the efficacy of these cases.

MATERIALS AND METHODS
Sixty-five eyes of thirtyfive patients were treated by the OptiVision™infrared laser and fiber delivery system purchased from SurgiLight (Orlando, Florida U.S.). Pre-operative and follow-up examinations included refraction, slit lamp examination, fundoscopy, IOP measurements, keratometry, scleral thickness measurement, and visual fields. The procedure was done under infiltration anesthesia using 4% Lidocaine with adrenaline. Topical anesthesia was instilled just prior to infiltration. After making four fornix-based conjunctival flaps in the intermuscular region and achieving hemostasis with bipolar cautery, four pairs of radial ablative scleral excisions were made – one pair in each quadrant. The length of each excision was approximately 4.5 mm in length starting 0.5 mm from the limbus. The separation between the paired excisions was approximately 2.0 mm. The depth of the grooves was about 75% of scleral thickness using the blue hue of choroid as the endpoint indicator.

The peritomy sites were closed with suturing. The patient was prescribed topical antibiotics
and steroids along with analgesic tablets.

RESULTS
The thirty-five patients treated ranged in age from 42 – 60 (mean 53.2). Seventeen percent were male and eighty-three percent were female. The pre-operative and postoperative results are compared in Table 1 below. Marking Ablation 24-hour post op One year post op

The near vision was tested at 35 cms reading distance. All patients’ distance vision after the surgery remained the same as pre-operative measurements. Out of the 35 patients, we have 6 patients that did not achieve good results, two of which we believe are due to a thin scleral thickness and the remaining four are probably due to shallow ablation during our learning
stage. Including all treated eyes, 71% of eyes are J2 or better and 80% are J3 or better in the near vision without glasses. Our results improved significantly, if we exclude those 6 patients with thin sclera or shallow ablations, 49% are J1 or better, 88% are J2 or better and 100% are J3 or better. The general observation was that subjective near vision improvement was noticed about 2 or 3 days after the procedure. It continued to improve over 2 weeks. The time interval for treating the fellow eye varied from 0–4 weeks (norm was 3 days). No myopic shift and no regression were noted during the follow-up period (maximum 12 months). No significant change in refraction for distance was noted. There was no induced astigmatism. In general there was a tendency for a lower IOP readings post-op. No significant complications were
encountered.

DISCUSSION
We recently recalled the first patients for their one year follow-up visits. All patients read J1 or J2. They excitedly reported being able to read, “even at night,” and were able to perform close work like sewing. It is believed that the absence of significant regression is due to a “fill-in” of the grooves by sub-conjunctival tissue. One hypothesis attributes the increased ciliary muscle functional range to increase elasticity of the scleral ring resulting from the ablation. This elastic” theory may provide the fundamental basis for the minimal regressions found in our new procedure using LAPR in comparison to the other scleral incision methods as shown in Table II. Upon follow-up, almost all patients show no measurable regression. From those cases we have treated, we are able to deduce some key findings: (a) patients with thin scleras are not good candidates for this procedure; (b) higher pre-operative Jeager readings (greater than J10) result in less near vision improvement post-operatively, this may be due to the “rigidity” of the sclera and ciliary muscle in these patients; (c) the minimal thermal effects to the sclera by using laser energy at the prescribed dosimetries and in a contact mode provides excellent, predictable results; (d) the ablation depth should be in the 75% – 85% range and an even cut (regression occurs in patients having shallow groove depth of less than 60%).

SUMMARY
Our initial clinical study demonstrates that LAPR procedure using the OptiVision infrared-laser for scleral tissue “ablation” (excision) is an effective and safe method for presbyopia reversal with minimal postoperative regression, unlike the results using other scleral “incision” methods. Longer term follow-up is necessary to evaluate stability of effect over one year.