INTRODUCTION
Presbyopia is one of the outstanding challenges raised in ophthalmology. Several methods attempt to correct presbyopia, but none of them have achieved totally satisfactory results. Following glasses and contact lenses, the traditional correction systems, different surgical techniques were developed, some modifying the anterior face of the cornea, the intraocular lens, and the most recent technique that attempts to recover the accommodation by means of
expanding the ciliary ring.

The sclera’s diameter enlargement in the first posterior studies showed hopeful results, but as in most of the surgical techniques, a regression occurred after the first months. J.T. Lin, Ph.D. studying this phenomenon, arrived at the conclusion that this regression was produced by the fibrosis in the treated sclera spaces, recovering the ciliary ring to its initial values.

To avoid the latter he proposed to perform sclera radial ablations, with a sufficient wave thickness to stop the fibrosis. The ablated space would fill in with tenon tissue, maintaining its elasticity and, thus, keep the ciliary’s “belt” expansion that follows these ablations.

MATERIALS AND METHODS
In our Department of Ophthalmology, we have performed a study to evaluate this therapeutic hypothesis. Twenty-four eyes of 12 consecutive patients diagnosed with presbyopia underwent surgery performed with the OptiVision™ Er:YAG laser of SurgiLight Inc., USA. The average age was 49.3 years, ranging from 46 to 55 years, and with presbyopia values between +1.0
and +2.5 Diopters. Eyes were accurately analyzed, examining the visual acuity, IOP values, corneal topography, pachymetry, biomicroscopy, fundoscopy, and campimetry. Postoperative follow-up examinations were done on day 3, week 2, week 6, and months 3 and 6. After all preoperative tests were performed and written, informed consent was obtained, the surgical
procedure was done under local anesthesia, subconjunctival infiltration using 2% 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 2.5 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 bipolar forceps. The patient was prescribed topical antibiotics and steroids along with analgesic tablets.

RESULTS
The preoperative data show a median addition of 1.83 ± 0.77 Diopters, visual acuity without correction around J5, and changing to J1 with the addition. Far Figure 1. – Laser assisted presbyopia sclerectomy (LAPS), post op 1 week. Figure 2. LAPS – post op 3 weeks. Figure 3. LAPS – post op 4 months. vision was better than 20/30 in all the cases. At the 2-week postoperative visit, all the patients presented improved near vision. All of them could read J3 or
better, and six patients, 50% of the group, increased to J1. The best-corrected visual acuity was of 1.29 ± 0.52 Diopters. These values remained relatively stable during the 6-week, with slight variations at 3 and 6 month post-operative visits. The far vision analysis showed a slight decrease (2 lines) at the first 72 hours postoperative, that was recovered in all the cases.

The corneal topography did not show changes induced by the technique, like in the visual field and corneal thickness. Average reduction of postoperative IOP values were 2.6 mm Hg. Fundoscopy and biomicroscopy intraocular exams did not show evidence of changes.
All patients reported conjunctival hyperemia and signs of irritation the first 48 hours. After this time, tolerance was excellent.

DISCUSSION
Loss of accommodation that appears with aging seems to be the cause of presbyopia. Different factors have been related to this fact: atrophy of the ciliary’s muscle, lens sclerosis, changes in the refractive index, balance alteration of the cornea and crystalline aberrations,
loss of the lenticular capsule elasticity, increase of lens size as other ectodermal tissues, etc.
Even though we still do not understand perfectly the physiopathologic mechanism of presbyopia, the fact is that the ciliary ring expansion would suppose a change in the relation between the zonula-lens, producing a slight improvement of the accommodative functioning, as it becomes evident in the Thornton, Fukasaku, Schackar and Lin techniques. The principal
difference in the Lin technique (patented by SurgiLight) with respect to the others, lies in using a laser, which performs the sclera groove ablations, achieving the most important result of avoiding the fibrosis and the regression of the results.

Although this hypothesis has to be proven, there are studies performed that showed good results, after more than a one year follow up (Dr. Oscar Mallo, Argentina). Our studies showed a significant improvement (P<0.001) in near vision without correction, from J5 to J2, with an average of 1.29 corrected diopters, maintaining these results during 6 months.

This data is certainly a very hopeful sign, and although more studies are needed, this technique has proven to be simple, only slightly traumatic, and with a low level of complications. Our patients reported a high level of satisfaction. All of them will be improving their vision in a short time, and their far vision has not been affected, except in the first two or three days postoperatively.

SurgiLight, Inc. (OTCBB: SRGL)
12001 Science Drive, Suite 140, Orlando, FL 32826 • Tel. (407) 482-4555 • Fax (407) 482-0505 • Website www.surgilight.com • Email surgilightsales@aol.com
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