TransPRK results: our published outcomes
A peer-reviewed study of 205 eyes treated with StreamLight TransPRK in Brisbane, published in the Journal of Ophthalmology in 2024 by Dr David Gunn and Rebecca Cox. This page explains what the study found, in plain English.
- 205 Eyes in the series, from 109 patients
- 95.6% Eyes seeing 20/20 or better without glasses
- 92.2% Eyes within ±0.50 D of the target prescription
- 88.3% Eyes with 0.50 D or less of astigmatism remaining
- None Eyes that lost two or more lines of best-corrected vision
Source: Gunn DJ, Cox RA. StreamLight single-step transepithelial photorefractive keratectomy (PRK) for myopia and myopic astigmatism. Journal of Ophthalmology. 2024. Outcomes measured at least three months after surgery.1
The study in brief
| Published | Journal of Ophthalmology, 2024, article 5597457. Peer reviewed and open access (full text, PubMed). |
|---|---|
| Authors | Dr David Gunn, corneal and refractive surgeon and co-founder of Focus Vision, and Rebecca Cox of the Queensland Eye Institute. |
| Design | Retrospective case series. All surgery was performed by a single surgeon at one Brisbane site between January 2020 and August 2023. |
| Who was treated | 109 patients, 205 eyes. Average age 32.5 years (range 21.5 to 54.3); 62% women. Short-sightedness from −0.63 D to −7.25 D (spherical equivalent), and 72% of eyes also had astigmatism. |
| Treatment | StreamLight single-step transepithelial PRK on the Alcon WaveLight EX500 excimer laser, with mitomycin C 0.02% applied for 20 seconds to reduce the risk of haze, and a bandage contact lens for the first five to seven days. |
| Follow-up | Outcomes were measured at least three months after surgery. The average time to the most recent visit was about ten months, and 162 of the 205 eyes had six months or more of follow-up. |
| Ethics and funding | Approved by the Royal Australian and New Zealand College of Ophthalmologists Human Research and Ethics Committee. Supported by an investigator-initiated trial grant from Alcon, declared in the paper. |
What the results show
Vision without glasses
196 of the 205 eyes (95.6%) could read the 20/20 line or better without glasses at their follow-up visit. Four out of five eyes saw as well without glasses after surgery as they had with glasses before it, and the mean efficacy index, which compares unaided vision after surgery with best-corrected vision before it, was 0.97.1
Accuracy of the correction
The average prescription left after surgery was −0.05 D, and 189 eyes (92.2%) finished within ±0.50 D of the planned correction. Plotting the correction attempted against the correction achieved gave a slope of 1.00, so the laser neither over-corrected nor under-corrected on average. There was no significant difference in accuracy between prescriptions up to −3.00 D and higher prescriptions.1
Astigmatism
181 eyes (88.3%) had 0.50 D or less of astigmatism remaining. Eyes that started with 1.50 D or more of astigmatism kept slightly more of it than eyes with less (an average of 0.41 D against 0.26 D), a difference of less than a quarter of a dioptre that the authors judged unlikely to matter to the patient.1
Safety
No eye lost two or more lines of best-corrected vision. Fewer than 4% of eyes lost one line, mostly attributed to dry eye that was under treatment, and two eyes had mild corneal haze. 14 eyes (6.8%) gained a line. The mean safety index, which compares best-corrected vision after surgery with before, was 1.01.1
What the numbers mean for you
20/20 without glasses is the standard definition of normal distance vision. Within ±0.50 D means the remaining prescription was no more than two of the smallest steps on a glasses prescription, an amount most people do not notice and would not wear glasses for. A safety index of 1.0 means best-corrected vision was unchanged by surgery; above 1.0 means it improved slightly on average.
The authors found these results comparable to published series of other transepithelial PRK platforms, conventional PRK and LASIK, and to a large network meta-analysis of laser corneal refractive surgery.1, 2 What separates TransPRK from LASIK is not the final result but the speed of getting there: the surface of the eye takes several days to heal and vision sharpens over the following weeks, which is why TransPRK is usually chosen for thinner corneas, irregular corneal surfaces, contact-sport players and others for whom a LASIK flap is less suitable.3
What the study does not tell you
- It is a retrospective series from a single surgeon at one site, not a randomised comparison with LASIK or other procedures.
- It covers short-sightedness with or without astigmatism. Eyes with long-sightedness or mixed astigmatism were not included.
- Follow-up varied, from three months to several years. Pain and the time the surface took to heal were not measured, and haze was not graded on a formal scale.
- These are group results. No procedure can guarantee a particular outcome, and your own result depends on your prescription, your corneal measurements and how your eyes heal. Your assessment and surgeon consultation are where that is worked out.
Why we publish our results
Auditing outcomes is part of how we practise. Publishing them in a peer-reviewed, open-access journal, with ethics approval and the funding declared, lets patients and colleagues check our results rather than take our word for them. The same discipline is behind the free Refractive Outcomes Analyzer that Dr Gunn and Dr Cronin built for surgeons to audit their own results.
TransPRK at Focus Vision costs from $3,500 per eye, all-inclusive except for prescribed medications and eye drops; the full price list is on our costs page. If a small prescription remains after surgery, our enhancement policy covers fine-tuning at no charge for two years. To find out whether TransPRK suits your eyes, start with a free optometrist assessment.
References
- Gunn DJ, Cox RA. StreamLight single-step transepithelial photorefractive keratectomy (PRK) for myopia and myopic astigmatism. J Ophthalmol. 2024;2024:5597457. pubmed.ncbi.nlm.nih.gov/39575318 · doi.org/10.1155/2024/5597457
- Wen D, McAlinden C, Flitcroft I, et al. Postoperative efficacy, predictability, safety, and visual quality of laser corneal refractive surgery: a network meta-analysis. Am J Ophthalmol. 2017;178:65-78. doi.org/10.1016/j.ajo.2017.03.013
- Shortt AJ, Allan BD, Evans JR. Laser-assisted in-situ keratomileusis (LASIK) versus photorefractive keratectomy (PRK) for myopia. Cochrane Database Syst Rev. 2013;(1):CD005135. pmc.ncbi.nlm.nih.gov/articles/PMC11848121
TransPRK results: common questions
Where can I read the full study?
The paper is open access, so anyone can read it free of charge. It was published in the Journal of Ophthalmology in 2024: Gunn DJ, Cox RA, StreamLight single-step transepithelial photorefractive keratectomy (PRK) for myopia and myopic astigmatism. Read it on the publisher's site or find it on PubMed.
Is TransPRK as accurate as LASIK?
In this series 92.2% of eyes finished within ±0.50 D of the planned prescription and 95.6% saw 20/20 or better without glasses, and the authors found the safety and accuracy comparable to published series of LASIK, conventional PRK and other forms of transepithelial PRK. The main difference between the two procedures is the speed of recovery: vision after LASIK is usually clear within a day, while the surface of the eye takes several days to heal after TransPRK and vision sharpens over the following weeks.
What does 20/20 without glasses mean?
It means the eye could read the 20/20 (6/6 in Australian notation) line of the eye chart with no glasses or contact lenses, which is the standard definition of normal distance vision. In the study, 196 of the 205 eyes reached that line or better at their follow-up visit, measured at least three months after surgery.
Did anyone lose vision in the study?
No eye lost two or more lines of best-corrected vision. Fewer than 4% of eyes lost one line, which the authors attributed mostly to dry eye that was being treated; two eyes had mild corneal haze. About 7% of eyes gained a line. The safety index, which compares best-corrected vision after surgery with before, was 1.01, meaning best-corrected vision was on average unchanged.
Who funded the study, and was it independently reviewed?
The study was supported by an investigator-initiated trial grant from Alcon, the maker of the laser, which the paper declares. It was approved by the Royal Australian and New Zealand College of Ophthalmologists Human Research and Ethics Committee, peer reviewed before publication, and the data are available from the authors on request.
Will I get the same result?
No procedure can promise a particular result, and these figures describe a group of eyes rather than any one person. The series covered short-sightedness from −0.63 D to −7.25 D, with or without astigmatism, in people aged 21 to 54. Your own outcome depends on your prescription, your corneal measurements and how your eyes heal, which is what your assessment and surgeon consultation are for. If a small prescription remains after surgery, our enhancement policy covers fine-tuning at no charge for two years.
Does Focus Vision use the same TransPRK technique as the study?
Yes. StreamLight is Alcon's name for single-step transepithelial PRK on its WaveLight excimer laser: the laser removes the surface layer and reshapes the cornea in one continuous no-touch treatment. It is the TransPRK technique described on our laser eye surgery page.
Still have questions?
Contact our specialist team today.
Written and reviewed by Dr David Gunn FRANZCO, FWCRS — Corneal, Cataract and Refractive Surgeon. Last reviewed: 16 October 2026