|Year : 2023 | Volume
| Issue : 1 | Page : 19-21
Transition to single-step transepithelial photorefractive keratectomy in the same session following intraoperative flap complication
Cem Ozturkmen1, Melisa Karslioglu2, Afsun Sahin2
1 Department of Ophthalmology, Goznuru Eye Hospital, Refractive Surgery Unit, Gaziantep, Turkey
2 Department of Ophthalmology, Koc University Hospital, Istanbul, Turkey
|Date of Submission||11-Aug-2021|
|Date of Acceptance||28-Jul-2022|
|Date of Web Publication||20-Jan-2023|
Davutpasa Street, No: 4, Topkapi, Istanbul
Source of Support: None, Conflict of Interest: None
Recently, a new variation of transepithelial PRK, called TransPRK, was introduced, in which both the epithelium and stroma are removed in a single step, in one ablation profile. In this report, we present a case of a 31-year-old male patient who was prepared for laser-assisted in-situ keratomileusis (LASIK) surgery but switched to TransPRK combined with mitomycin C (MMC) application following intraoperative flap complication in one eye. As a result of the timely and on-site intervention, no haze was seen. TransPRK may be considered as an alternative with the advantages of reduced risk of postoperative pain and haze formation in intraoperative incomplete flap formation.
Keywords: Haze, incomplete flap, LASIK, MMC, TransPRK
|How to cite this article:|
Ozturkmen C, Karslioglu M, Sahin A. Transition to single-step transepithelial photorefractive keratectomy in the same session following intraoperative flap complication. Indian J Ophthalmol Case Rep 2023;3:19-21
|How to cite this URL:|
Ozturkmen C, Karslioglu M, Sahin A. Transition to single-step transepithelial photorefractive keratectomy in the same session following intraoperative flap complication. Indian J Ophthalmol Case Rep [serial online] 2023 [cited 2023 Feb 1];3:19-21. Available from: https://www.ijoreports.in/text.asp?2023/3/1/19/368210
In photorefractive keratectomy (PRK), corneal epithelial removal is carried out with laser phototherapeutic keratectomy, followed by a laser refractive ablation of the stroma. This technique has been used since the 1990s; however, unfortunately, due to the prolonged surgery time with old-generation lasers, increased pain, and a lack of adjusted nomograms, this technique was not widely used. Recently, a new variation of transepithelial PRK, called TransPRK, was introduced by Schwind eye-tech-solutions. In TransPRK, both the epithelium and stroma are removed in a single step, in one ablation profile, which takes into account the literature data estimating the central epithelial thickness of a normal cornea to be 55 μm and 65 μm at 4 mm from the center. We present a case of a 31-year-old male patient who was prepared for laser-assisted in-situ keratomileusis (LASIK) surgery but switched to TransPRK intraoperatively, following flap complication in the right eye.
| Case Report|| |
A 31-year-old male patient was referred to us at the request of getting rid of his glasses. He had no ocular or systemic disease. His best corrected visual acuity was 20/20 with cycloplegic refraction (Right: −4.0D, Left: −4.0–0.50 × 130°D). The intraocular pressure, anterior segment, optic nerve, and retina was normal, bilaterally. The preoperative central corneal thickness values were 535 μm and 546 μm, respectively, in the right and left eyes. After corneal topographic imaging [Figure 1]a and [Figure 1]b, we planned LASIK surgery for both eyes using the SCHWIND Carriazo-Pendular microkeratome with a 130-micron head. Both eyes were prepared and draped similarly. In the right eye, we observed that the corneal flap formed up to the inferior 1/3 of the pupillary axis [Figure 2]a and intraoperatively, we decided to switch to TransPRK for his right eye and PRK for his left eye. The incomplete flap was put back in its place. After the flap was positioned properly via painting-like movements with two wet sponges and waiting for 2 min for the exit of interface fluid, TransPRK was performed for his right eye with the 6.5 mm ablation zone. Because we did not have enough TransPRK experience in higher refractions, after encountering an intraoperative flap-related complication, we decided at that moment that conventional PRK for the left eye would be much safer and PRK was performed for his left eye using the Schwind Amaris 500E excimer platform (SCHWIND® eye-tech-solutions GmbH, Kleinostheim, Germany). The target refraction was emmetropia. In the right eye, the balanced salt solution was applied gently with a wet sponge, painting-like movements, to provide an equal wetting of the whole corneal surface. In the left eye, an 8.5-mm well, filled with 20% ethanol, was placed centrally on the cornea for 30 s and then ethanol was soaked fully with a sponge to get rid of it. After ablation, mitomycin C (MMC) 0.02% was applied to both the eyes for 25 s, and then the stromal bed was irrigated with plenty of balanced salt solution to remove MMC from the surgical field. Following surgery, a soft bandage contact lens was applied for 3 to 4 days. The patient was instructed to use moxifloxacin 0.05% (Novartis®, Alcon Inc., Geneva, Switzerland) eye drops four times a day for 1 week and loteprednol 0.05% (Bausch& Lomb® Inc., New York, United States) eye drops four times a day, then tapered during the following months.
|Figure 1: The corneal topography images of a 31-year-old-male patient who had TransPRK and PRK procedures, on the right eye and left eye, respectively. (a) Preoperative imaging of the right eye. (b) Preoperative imaging of the left eye|
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|Figure 2: The anterior segment examination of the right eye. (a) The incomplete flap formation. (b) The intact and smooth flap formation and absence of haze|
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At 1 month postoperatively, his uncorrected best visual acuity was 20/20 on both eyes, with cycloplegic refraction +0.50 D on both eyes. The flap was intact on the right eye and no haze formation was seen in both eyes [Figure 2]b. Postoperative central corneal thickness values were 444 μm and 457 μm, respectively, in the right and left eyes. The corneal topographic examination was consistent with myopic refractive surgery postoperatively [Figure 3]a and [Figure 3]b.
|Figure 3: The corneal topography images of a 31-year-old-male patient who had TransPRK and PRK procedures, on the right eye and left eye, respectively. (a) Postoperative imaging of the right eye. (b) Postoperative imaging of the left eye|
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| Discussion|| |
Previous studies have shown that TransPRK is sufficiently effective and is a safe procedure in the treatment of low, moderate, or high myopia, and for this reason, it is becoming increasingly popular. The main advantages of TransPRK are the absence of flap-related complications, minimal trauma to the eye, less deterioration in corneal biomechanics, and the possibility of reoperation. In addition to the fact that the use of MMC in refractive surgery reduces postoperative haze formation, customized application of MMC in TransPRK has also been studied, and the same effect has been observed. However, the indication for MMC application in mild-to-moderate myopia is still controversial because comparable visual outcomes had been achieved. In our case, the patient had moderate myopia in both eyes and the maximum ablation depth was 117.36 μm in the right eye and 70.95 μm in the left eye. We applied MMC for 25 s bilaterally and saw no haze on both eyes after 1 month of the surgery.
Solely, the flap-related complications may induce higher order aberrations. In our case, although the possibility of an increase in these aberrations was caused by the transition to trans PRK in the same session, in the postoperative follow-up, the absence of visual complaints in this direction suggested that the visual quality has been not affected much.
| Conclusion|| |
In conclusion, in patients having deep orbita, narrow palpebral fissure, blepharospasm, or intraoperative incomplete flap formation TransPRK may be considered as an alternative with the advantages of reduced risk of postoperative pain and haze formation with faster postoperative improvement without flap-related complications. Certainly, new comparative studies are needed to reveal all the positive and negative aspects of this technique.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]