LASIK Hyperopia Treatment & Management

This study included the first consecutive 49 eyes with preoperative hyperopia ranging from +1.25 D to +6.25 D with less than 0.75 D astigmatism and followed for 6 months postoperatively.^[19] A Lambda Physik 193-nm argon fluoride excimer laser at a fluence of 130 mJ/cm² was used for these cases.^[5]

Every patient underwent protocol preoperative ophthalmic tests that included a thorough slit lamp biomicroscopy, manual keratometry and autokeratometry, corneal topography, corneal pachymetry, specular microscopy, cycloplegic refraction, and recorded uncorrected and best-corrected visual acuity.^[19]

All eyes were operated on under topical anesthesia. The corneal flap was created using the Chiron automated corneal shaper after making an epithelial mark with the Gulani LASIK marker and checking the intraocular pressure with the Barraquer tonometer. The flap was deliberately decentered nasally. The flap was gently lifted and reflected on itself nasally.

With the patient fixating at the fixation light, the Gulani triple lens marker was used to mark the anterior stroma with 3 concentric rings of 4.5-, 4-, and 3.5-mm diameters, respectively. Using a specially designed cupped lens forceps, the 4.5-mm lens was placed onto the stomal bed on the 4.5-mm mark and gently tapped into place as shown below. See the image below.

The flap hinge protector was used to prevent inadvertent ablation of the corneal flap hinge. In some cases, the globe stabilizer was used for apprehensive patients with excessive eye movements despite good visibility of the fixation light.^[20] The pretested and calibrated laser performed nomogram-directed ablation with a beam diameter of 7 mm.

A suction nozzle was held close to the eye by an assistant during ablation to address the plume and other unwanted products of the laser-corneal interaction. Following this first stage of hyperopic laser ablation, the 4.5-mm lens was lifted off the cornea and replaced by a 4-mm lens, which was then centered within the ablation edge of the previous laser-corneal interaction. Ablation is continued, followed by the final stage using the 3.5-mm lens.

After completing the hyperopic ablation using these 3 lenses successively, the surgeon can appreciate the concentric ring pattern of 3 rings with smooth edges under high magnification as shown in the images below. The stromal bed is now irrigated with balanced salt solution using the Gulani triple function LASIK cannula, while the corneal flap is floated back into position in alignment with the previously placed epithelial marks. Then, the flap is squeegeed gently using the bulbous tip of the cannula and air dried at the edges for 1 minute. The flap adherence is tested by applying the striae test, and, after speculum removal, it is tested by the blink test. See the images below.

A study of 60 eyes concluded that LASIK is an effective procedure for treatment of hyperopia. Pupil-centered and vertex-centered treatments provide similar visual and optical outcomes. However, in eyes showing large temporal pupil decentration, pupil-centered ablation seemed to produce a lower amount of coma and, as a consequence, a reduced loss of BCVA compared with vertex-centered patients.^[21]

Dry eye is common after LASIK, and over-the-counter preservative-free lubricants are important.^{[22, 23]}

Patients usually are seen the day after surgery, 2 weeks after surgery, and then as needed.^[9]

For excellent patient education resources, visit eMedicine's Eye and Vision Center. Also, see eMedicine's patient education article Vision Correction Surgery.

Complications include displaced flap, corneal perforation, interface debris, and diffuse lamellar keratitis.^{[22, 24]}

The results of hyperopic LASIK have been encouraging and relatively stable at 6 months postoperatively.^[25] Refractive stability occurred from 1-2 weeks postoperatively and remained stable at 6 months. The results with uncorrected visual acuity were similar, with vision stabilizing from 1-2 weeks postoperative.

In this study, patients who underwent LASIK had a mean preoperative sphere of +2.6 D. Ninety percent of the eyes attained 20/40 or better postoperative unaided vision, while 50% of eyes were 20/20. These results correlated with a hyperopic LASIK report of a similar preoperative hyperopic category of patients in which 95% of eyes achieved 20/40 or better unaided vision.^{[25, 26]} No lines of best-corrected visual acuity were lost.

In this study series, no significant haze, decentrations, central islands, irregular astigmatism, or interface deposits/inflammation were observed.^[27] Epithelial ingrowth did occur in 3 cases. This epithelial ingrowth was mild and restricted to the periphery. In these cases, the corneal flaps were uniform in thickness and well aligned as were the corneal topographies.^{[28, 29, 30]} At the 8-month postoperative gate, one of these eyes underwent flap lifting and interface cleansing. A specially designed flap lifter was used to elevate the flap without eroding the surgically steepened stromal mound.

See related CME at Corneal Ectasia Following LASIK Surgery.^{[31, 32]}

The surgical correction of hyperopia remains a challenge and a worthy pursuit in the field of refractive surgery.^[22] The basic principle of corneal surgery for hyperopic correction remains in carving a lens shape that is steeper in the center by graded removal of tissue in the periphery.^[27]

The possibility of regression will continue to be a concern in such a surgical profile because of the natural or sometimes hyperplastic healing response of the cornea to fill in this ablated step between the treated and untreated zones, thereby not only resulting in loss of effect over time but also inducing an astigmatic error in case of uneven fill-ins. With the surge of technological advances and the availability of smoother ablation systems, along with microkeratomes aiding larger corneal flaps, these concerns may be addressed.^{[13, 14, 15, 16, 17, 33]} This author has no experience with piggyback intraocular lenses.^[34]

In the author's experience, LASIK is presently the treatment of choice for this grade of hyperopia.^[10] A welcome surprise in the results was a simultaneous improvement in near vision associated with this hyperopic LASIK technique. An investigation occurred to check if cylinder was being induced, thereby aiding the patient's presbyopia; the investigation revealed no significant induction of cylinder. Therefore, this improvement in presbyopia could be a direct result of the corneal multifocality that results from this work. Such postablation corneal multifocality has been previously observed and reported.

This improvement is a welcome advantage in the presbyopic age group and has remained stable at the 6-month postoperative gate. Hyperopic LASIK using these intra-ablative contact lenses has been successful at the 6-month postoperative period with no loss of best-corrected visual acuity. The future of refractive surgery seems promising as a transition is predicted from cornea-focused refractive surgery with its inherent variabilities toward intraocular surgery using multifocal lenses and phakic implants.^{[13, 14, 15, 35, 36]}

At this time, the important issue is that hyperopia is finally receiving its due attention.