Tracker-assisted laser in situ keratomileusis for myopia using the autonomous scanning and tracking laser: 12-month results

doi:10.1016/S0161-6420(02)01013-8

Ophthalmology

Volume 109, Issue 5, May 2002, Pages 965-972

Presented in part at the ESCRS, Brussels, September 2000, and at the annual meeting of the American Academy of Ophthalmology, Dallas, Texas, October 2000.

https://doi.org/10.1016/S0161-6420(02)01013-8 Get rights and content

Abstract

Objective

To determine the safety, efficacy, and predictability of the Autonomous scanning and tracking laser for the correction of myopia and myopic astigmatism with laser in situ keratomileusis (LASIK) procedure.

Design

Retrospective, noncomparative case series.

Participants

The first 129 consecutive eyes with up to −13.00 diopters (D) of myopia and −5.00 D of astigmatism.

Intervention

Myopic tracker-assisted LASIK (T-LASIK) using the Autonomous Laser (Alcon Summit Autonomous, Waltham, MA) and Hansatome microkeratome (Bausch & Lomb Surgical, Bracknell, England).

Main outcome measures

Uncorrected visual acuity (UCVA), manifest spherical equivalent (MSE), best spectacle-corrected visual acuity (BSCVA), and complications were studied.

Results

At 12 months, the mean MSE was −0.02 ± 1.01 D, with 79.1% of eyes within 0.5 D and 89.9% of eyes within 1 D of the intended correction. UCVA was 20/20 or better in 71.4%, 20/25 or better in 78.5%, and 20/40 or better in 92.8% of eyes. Two eyes (1.6%) lost 2 lines and five eyes (3.8%) gained 2 lines of BSCVA. Sixteen eyes (12.4%) required retreatment to correct residual myopia or astigmatism. After retreatment, 14 of 16 eyes were within 0.5 D of emmetropia. Nine eyes (6.9%) had minor flap complications; two eyes (1.6%) had grade 2 diffuse lamellar keratitis, of which one eye had associated peripheral flap melt. One eye showed slight decentration; this eye was rolling throughout the procedure. All eyes had some dryness, with 10% severe enough to require temporary punctual occlusion with plugs.

Conclusions

T-LASIK for myopic astigmatism with the Autonomous Laser is relatively safe, effective, and predictable. The tracker seems to be effective, and the complications are relatively few. Retreatment rates are acceptable and can be performed safely and effectively to improve visual outcome. The outcomes are comparable with other published data.

Section snippets

Patients and methods

We performed a retrospective analysis of all eyes treated at one center (Rosen Eye Surgery Centre) with at least 12 month follow-up since taking delivery of the Autonomous Laser in May 1998. Ethics committee approval was not required for this study. Data of all patients undergoing T-LASIK for myopia and compound myopic astigmatism were included in the study. Until July 2000, 12-month data were available for 129 eyes treated with T-LASIK for spherical myopia between −0.50 and −10.00 D or for

Results

A total of 137 eyes was treated during this period. Eight eyes were lost to follow-up. Twelve-month data are available for 129 eyes, representing a 94.2% accountability. Figure 1 shows the age distribution of the patients. Half the patients were in the presbyopic age range (40+). Ninety-three percent of the treatments performed were applied over a 6.5-mm optical zone and 1.0-mm blend zone, and only 5.4% were applied with 6.0-mm optical zone.

Discussion

These clinical results show that the Autonomous Laser is relatively safe, predictable, and effective in correction of low-to-moderate myopia and myopic astigmatism over 1 year. Moreover, the results show excellent long-term stability, which is achieved at a very early stage, within 1 month. No patient lost more than 2 lines of best-corrected visual acuity, and only two patients lost 2 lines. One of these patients had a flap melt because of untreated lid margin disease.

The effectiveness of our

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To investigate the efficacy and safety of LASIK over a 5-year postoperative period.
Observational case series.
We examined 779 eyes in 402 patients with myopia or myopic astigmatism who underwent LASIK to correct their refractive errors and received regular postoperative assessments for 5 years.
Postoperative examinations were performed 1 day; 1 week; 1, 3, and 6 months; and 1, 2, 3, 4, and 5 years after LASIK surgery.
We evaluated changes in uncorrected visual acuity (UCVA) (logarithm of the minimum angle of resolution [logMAR]), manifest refraction, best-corrected visual acuity (BCVA) (logMAR), intraocular pressure, corneal thickness, corneal endothelial cell counts, and complications.
Preoperative UCVA of 1.27 improved to −0.03 at 1 day after surgery and −0.08 at 1 month and revealed minimal but significant decreases thereafter. Postoperative manifest refraction was also improved by surgery, showing minimal but significant regression after 1 year. Final BCVA loss was seen in 10 eyes of 7 patients; in 7 cases, there were obvious reasons such as the progression of cataracts in 3 eyes, epithelial disintegrity due to dry eye in 2 eyes, irregular astigmatism due to flap striae in 1 eye, and age-related macular dystrophy in 1 eye. Intraocular pressure and corneal thickness decreased by 4.0 mmHg and 76.9 μm, respectively, due to surgery, but remained stable throughout the follow-up period. Corneal endothelial cell counts (2689.0±232.9 cells/mm² before surgery) showed a statistically significant decrease at 5 years after surgery (2658.0±183.1 cells/mm²; 1.2% loss for 5 years), likely within the range due to physiological age-related loss. No serious, vision-threatening, irreversible complication such as keratectasia or progressive endothelial cell loss was observed.
LASIK surgery is an effective and safe procedure for correcting myopia/myopic astigmatism as long as inclusion and exclusion criteria are strictly respected. However, minimal regression occurred during the 5-year investigative period.
Optical Correction with Refractive Surgeries and Prosthetic Devices
2006, Borish's Clinical Refraction
The family physician and eye microsurgery (LASIK)
2005, Semergen
Este trabajo pretende ayudar al médico de Atención Primaria en el manejo de los pacientes intervenidos de microcirugía ocular (LASIK); esta técnica se utiliza para corregir miopía de hasta 14 dioptrías, hipermetropía y astigmatismos de hasta 6 dioptrías. El paciente “ideal” es el joven mayor de 20-21 años, con acomodación conservada y miopía entre −1.00 y −12.00 dioptrías. Señalamos las contraindicaciones y molestias habituales, así como la actuación ante las patologías oculares más frecuentes: la conjuntivitis, que se trata de igual forma que en el paciente no intervenido, las contusiones y erosiones, que deben ser examinadas con la precisión y cuidado habitual, comprobando que no existen desplazamientos o pliegues en la solapa corneal, el fondo de ojo, que se realiza igual que en el resto de pacientes. En algunos casos es posible observar la zona de ablación como un disco bien delimitado. La incidencia de cataratas o de presbicia es la misma en los pacientes intervenidos con LASIK que en los no intervenidos.
This study aims to help the Primary Health Care physician in the management of patients operated on with eye microsurgery (LASIK). This technique is used to correct shortsightedness up to 14 diopter and farsightedness and astigmatism up to 6 diopters. The “ideal” patient is a young person aged 20-21 with conserved accommodation and shortsightedness between -1.00 and -12.00 diopters. We indicate the contraindications and usual discomforts and the action against the most frequent eye diseases: CONJUNCTIVITIS is treated the same way in non-operated patient. CONTUSIONS and EROSIONS should be examined with exactness and usual care, verifying that there are no displacements or folds in the corneal overlap. The EYE FUNDUS is done as in the remaining patients and, in some cases, it is possible to observe the ablation area as a well defined disc. The incidence of CATARACTS or PRESBYOPIA is the same in patients operated on with LASIK as those who are not operated.
Wavefront-guided LASIK with the Zyoptix 3.1 system for the correction of myopia and compound myopic astigmatism with 1-year follow-up: Clinical outcome and change in higher order aberrations
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Citation Excerpt :
However, there was still undercorrection in the case of myopia beyond −6.5 D (Fig 3). Compared with the standard LASIK treatments,1,21,22 more patients were within 0.5 D or 1.0 D of emmetropia. Stability with a mean regression of −0.1 over 11 months was excellent for myopic corneal refractive surgery and was very much comparable to that of the standard LASIK procedure.
To assess safety, efficacy, predictability, stability, and change in aberrations after wavefront-guided LASIK for myopia and myopic astigmatism.
Prospective, nonrandomized, self-controlled trial.
Wavefront-guided LASIK was performed in 97 eyes in a 1-year trial. Treated eyes had a mean subjective manifest spherical equivalent (SE) of −5.22±2.07 diopters (D), with a range of −0.25 to −9.00 D of myopia and 0 to −3.25 D of astigmatism.
After a microkeratome cut, a wavefront-based excimer ablation (Zyoptix 3.1) was performed. The full treatment to achieve emmetropia of an early nomogram provided by the system manufacturer was used in all procedures.
Safety, efficacy, predictability, and stability were evaluated at 1, 3, and 12 months postoperatively. Wavefront changes of higher order aberrations (HOAs) at 1 year were determined for pupil sizes of 3.5 and 6 mm.
At 1 year postoperatively, uncorrected visual acuity (VA) was 20/20 or better in 83% of the eyes, and 20/40 or better in 98%. The mean subjective manifest SE at 1 year was −0.25±0.43 D; it was within 0.50 D in 77% and within 1.0 D in 95%. No eye lost ≥2 lines of best spectacle-corrected VA (BSCVA) at 1 year postoperatively; 40 eyes gained 1 line of BSCVA, and 5 eyes gained 2 lines. The total HOA root mean square (RMS) increased on average by a factor of 1.23±0.57 with a 3.5-mm pupil; for the 6 mm pupil, the increase factor was 1.52±0.36. No change or reduction in the total HOA RMS was observed in 45.5% of the eyes for a 3.5-mm pupil and in 20.6% for a 6-mm pupil. There was a significant increase of primary spherical aberration (Z 4,0) by a factor of 4.11±10.17 for 3.5-mm pupils and 4.31±6.76 for 6-mm pupils.
Wavefront-guided LASIK using Zyoptix 3.1 is an effective and safe procedure for the treatment of myopia and myopic astigmatism. Although in close to half of the eyes HOAs could be reduced, there was still undercorrection and induction of HOAs with the algorithm employed.
The effect of daily use of brimonidine tartrate on the dark-adapted pupil diameter
2004, American Journal of Ophthalmology
To investigate the effect of daily brimonidine tartrate 0.15% on the dark-adapted pupil diameter.
Observational case series.
Ten normal volunteers administered brimonidine to their right eyes once daily. Four to six hours later, infrared pupil photographs were taken after dark adaptation. Measurements were performed at baseline; on treatment days 1, 5, 11, and 18; and on washout days 1 and 2.
One subject had no response. The nine responding subjects showed an average maximum antimydriatic effect of −1.63 mm (range, −0.57 mm–−2.30 mm); all subjects experienced tachyphylaxis. Five subjects showed rebound mydriasis (mean maximum rebound +0.87 mm larger than baseline; range 0.50 mm–1.22 mm). The untreated pupil also responded, showing antimydriasis (two subjects), rebound mydriasis (two subjects), or paradoxical direct mydriasis (one subject).
Once-daily use of brimonidine tartrate to prevent dark-induced pupil dilation can lead to tachyphylaxis and rebound mydriasis.
Tracker-Assisted LASIK [3]
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¹: The authors have no proprietary interest in any of the materials presented in this article.

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Article for CME CreditTracker-assisted laser in situ keratomileusis for myopia using the autonomous scanning and tracking laser: 12-month results1

Abstract

Objective

Design

Participants

Intervention

Main outcome measures

Results

Conclusions

Section snippets

Patients and methods

Results

Discussion

J Cataract Refract Surg

J Cataract Refract Surg

Ophthalmology

J Cataract Refract Surg

Ophthalmology

Effect of decreasing surface and interface irregularities after photorefractive keratectomy and laser in situ keratomileusis on optical and functional outcomes

J Refract Surg

A computer model for predicting image quality after photorefractive keratectomy

J Refract Surg

Article for CME Credit
Tracker-assisted laser in situ keratomileusis for myopia using the autonomous scanning and tracking laser: 12-month results¹