A retrospective chart review performed from January 2009 to October 2013 assessed 1009 cases that underwent LASEK treatment using 20% alcohol and 120 mm eye spatula for epithelium mobilization; the STAR S4 IR^TM Excimer Laser was used to treat the eye. Evaluation of intraoperative flap events was conducted to assess the efficacy behind this minimal technique posed by surgeon, Dr. Samir Melki. Out of 1009 cases, 72.35% operative eyes showed complete flap preservation, 17.65% flap tears, and 10.01% flaps discarded, demonstrating the viability in applying this technique. All patients considered were required to have a pre-operative consultation to identify any possibly risk factors before surgery. For the purposes of this study, we investigated if age played a significant role in the intraoperative success of mechanically mobilizing the epithelium after 40-second alcohol exposure. We found that patients 50 years and older were statistically different from their younger counterparts (e.g. 20 to 29, 30 to 39, 40 to 49). They were more at risk for less epithelial preservation (e.g. flap equal to or less than 180 degrees) and overall flap removal (p < 0.001). There were no statistically significant differences between the age group 20 to 29 and 30 to 39; however, there was a relatively significant disparity in successful flap events for patients in their 20s versus those in their 40s (p < 0.001) suggesting that as one ages, the likelihood of flap tear increases.

Refractive surgery is designed to minimize the need for glasses and/or contact lenses and is often used for convenience, cosmetic or occupational purposes. The two most common types of laser eye surgery are LASIK and LASEK. During LASIK, the first step is the creation of the corneal flap using either a femtosecond laser or a mechanical microkeratome. The femtosecond laser has been seen to create more uniform flaps that reduce the risk of intraoperative and postoperative flap complications compared to the mechanical microkeratome. The purpose of this study was to investigate the effect on visual outcomes of second surgery LASEK on patients following aborted LASIK surgeries due to Femtosecond laser flap complications. LASIK was performed as planned and the corneal flap was created by the femtosecond laser but could not be lifted when a surgical cut was made. The procedure was aborted and LASEK was performed within a few weeks to attain the desired vision correction. A total of 14 patients were identified over a 6-year period ranging from 2009-2015. Most patients underwent surface ablation within two weeks of the initial aborted procedure. 12 of the 14 patients had a UCVA of 20/20, while the remaining 2 patients had a UCVA of 20/25 at their last postoperative visit. None of the patients required surgical enhancements despite the flap complications and no major postoperative complications were noted in any of the patients. Provided the corneal flap was well centered and there was no evidence of microstriae or epithelial ingrowth, surface ablation LASEK can be performed within a week of the aborted LASIK procedure to minimize discomfort and trauma to the patient. LASEK is associated with a slightly longer healing time but no evidence of corneal or retinal issues were noted in these patients. None of the patients experienced any significant changes in refraction between surgeries and was thus a reliable indicator of refractive stability following the flap complication. No significant differences were noted with delaying the second surgery LASEK as several patients attained 20/20 vision when it was performed within a week. The most common flap complication was the formation of an incomplete flap that could not be lifted. The cause could not be identified.

Syfte: Studiens syfte var att undersöka hur refraktiv kirurgi ser ut i Sverige idag, vilka komplikationer som finns och vilka metoder som används genom att göra en kort redovisning av de vanligaste teknikerna FS-lasik, LASEK, TransPRK och RLE som finns inom refraktiv kirurgi och med hjälp av en enkät ta reda på de olika komplikationerna mellan olika åldersgrupper.  Metod: En enkätstudie inom refraktiv kirurgi i Sverige genomfördes. Enkäten var webbaserad och skapad i Google Docs (http://docs.google.com). Enkäten innehöll totalt 11 frågor som handlade om patientens tidiga refraktion, operationsmetod och ögonhälsa efter operationen. Enkäten spreds via sociala medier som Facebook, Instagram, Twitter, olika forumsiter, samt mail. En del av enkäten var även fördelad på två olika ögonkliniker i Lund. Resultat: Resultaten av enkäten visar att det finns inte någon skillnad i komplikationsgraden mellan de olika åldersgrupperna och komplikationerna efter kirurgin beror på typen av metod och patientens synfel och brytningsfel.  Slutsats: Vid de olika metoderna förekommer olika komplikationer och ju mer närsynt patienten är desto större är risken för komplikationer i samband med operationen. / Refractive surgery is an effective method for correcting visual refractive errors. The method has evolved quickly over the past decade. The aim of this study was to examine what refractive surgery is in Sweden today. What complications exist and which methods are used, are described by making a presentation of the refractive surgery techniques FS-LASIK, LASEK, TransPRK and RLE. This was done by a survey to find out the various complications between different age groups. A web-based survey was disseminated trough social media like Facebook, different forum sites and e-mail. The survey was also submitted to various eye clinics. The respondents were asked questions about their age, gender, the surgical method used and the complications after surgery. The results of the survey showed that there is no difference in the complication rate between the different age groups. Complications only depend on the type of method used and the patient’s refractive errors.

Intraocular pressure (IOP) measurement is a routine procedure and a fundament in glaucoma care. Elevated IOP is the main risk factor for glaucoma, and to date, reduction of IOP is the only possible treatment. In a retrospective clinical material, the prevalence of open angle glaucoma was estimated on the west coast of Iceland. IOP measurement and optic nerve head examination were used to capture glaucoma suspects, within the compulsory ophthalmological examination for the prescription of eye glasses. The results were mainly in agreement with a recent prospective study in the same region. This indicated that retrospective data, under certain conditions, may contribute with useful information on the prevalence of glaucoma. However, normal tension glaucoma is underestimated if perimetry and/or fundus photography are not included in the examination. Three studies focused on the measurement of IOP. Goldmann applanation tonometry (GAT) is the standard method. GAT is affected by corneal properties, e.g. central corneal thickness (CCT) and corneal curvature (CC). Refractive surgery changes these properties. This has put focus on how corneal biomechanics translate into tonometric errors and stimulated the development of new methods. As a result, Pascal ® Dynamic Contour Tonometry (PDCT) and Icare® rebound tonometry have been introduced. A method under development by our research group is Applanation Resonance Tonometry (ART). It is based on resonance technology and estimates IOP from continuous measurement of force and contact area. Comparison of PDCT, Icare and GAT in a prospective study showed that the concordance to GAT was close to the limits set by the International Standard Organization (ISO) for PDCT, while Icare was outside the limits. To investigate if laser-assisted subepithelial keratectomy (LASEK) affects tonometry, a study was performed where measurements with GAT, PDCT and ART were obtained before, three and six months after LASEK. The hypothesis was that PDCT and ART would be less affected by LASEK than GAT. The results showed a statistically significant reduction of measured IOP three and six months after LASEK for all tonometry methods. Change in visual acuity and IOP between three and six months suggested a prolonged postoperative process. A servo-controlled prototype (ART servo) was developed. A study was undertaken to assess the agreement of ARTservo and a further developed v manual prototype (ART manual) with GAT. The study design was in accordance with the requirements of the ISO standard for tonometers. ARTmanual fulfilled the precision requirements of the ISO standard. ARTservo did not meet all the requirements of the standard at the highest pressure levels. Four tonometry methods, GAT, PDCT, Icare and ART, were investigated. None of them was independent of both CCT and CC. The inconsistencies in the results emphasize the importance of study design. A meta-analysis comprising healthy eyes (IOP ≤ 21 mmHg) in the three papers, revealed age as an important confounder. In summary, glaucoma prevalence in Iceland was investigated and the results indicated that a retrospective approach can contribute with meaningful information. ART and PDCT had a similar agreement to GAT. ART manual fulfilled the precision requirements set by the ISO-standard, ARTservo and PDCT were close, while Icare was distinctly outside the limits. All tonometry methods were affected by LASEK and no method was completely independent of corneal properties.

INTRODUCTION/PURPOSE: Billions of people world wide suffer from refractive errors requiring glasses, contact lenses, or other means of correction to enable them to see better. Many people seeking permanent means to correct their vision consider undergoing corneal refractive laser surgeries (CRLS), photorefractive keratectomy (PRK), laser-assisted subepithelial keratectomy (LASEK), or laser in situ keratomileusis (LASIK). These surgeries have been shown to improve vision, but are not without risks for complications intra-operatively and postoperatively. Few studies have looked at the long-term incidence of postoperative complications such as dry eyes and visual aberrations and the associated preoperative risk factors. It is the aim of this study to examine the long-term incidence of dry eyes and visual aberrations (starbursts, halos, glare) after CRLS, and assess for preoperative risk factors associated with the persistence of these symptoms after surgery. METHODS: This study consisted of 319 patients identified for undergoing PRK, LASEK, or LASIK, at Boston Laser between December 2009 and January 2014. The participants in this study completed a novel online questionnaire consisting of questions to assess dry eye and visual aberration symptoms, and included questions adapted from the Ocular Surface Disease Index (OSDI). Postoperative dry eye symptoms were measured based on the OSDI score and a new dry eye measurement score created for this study's questionnaire. Presence or absence of visual aberration symptoms postoperatively were measured based on a score created for this study and derived from the calculation of the OSDI score. Additionally, a retrospective chart review was conducted of the 319 participants' medical charts to gather and assess for preoperative risk factors related to the long-term incidence of both dry eye and visual aberration symptoms. RESULTS: Our data found a significant association (p < 0.05) that suggests a relationship between development of long-term dry eye symptoms and the following preoperative variables: pupil size, flap thickness, and dry eye risk assessment (including: Zone Quick test values ≤ 9.0mm, contact lens use, and dry eyes with and without contact lenses). No significant association (p > 0.05) was found between the novel dry eye score and the preoperative factors, but it did approach significance with two variables, necessitating further investigation: gender and actual ablation. No significance (p >0.05) was found in the association between the preoperative dry eye risk assessment and severity of postoperative symptoms as gathered using the OSDI score. Our data found a significant association (p < 0.05) that suggests an increased risk for development of long-term visual aberrations symptoms postoperatively with the following preoperative variables: cylindrical manifest refraction, flat K, and greater actual flap thickness. As well as identifying two other possible variables that approached significance requiring further investigation: steep K and preoperative visual aberrations risk (including: spherical manifest refraction &#8805; -6.00, astigmatic manifest refraction ≥ -2.00, and pupil diameter ≥ 7.0). The data showed a significant association (p < 0.05) between postoperative symptom presence and the aforementioned preoperative visual aberrations risk. Our data showed no significance (p > 0.05) when comparing the difference between mean OSDI, dry eye, and visual aberration scores between participants grouped by years since surgery. DISCUSSION/CONCLUSION: Our data found a significant relationship between long-term dry eye risk after CRLS and preoperative pupil size, flap thickness, and dry eye risk assessment. Similarly the data also displayed a significant association between long-term visual aberration risk after CRLS and greater preoperative cylindrical manifest refraction, flat K, and flap thickness. These findings contribute to the risk factors identified in similar short-term follow-up studies, and support the need for increased research into the risk factors and long-term incidence of dry eyes and visual aberrations after CRLS. While the data showed no significance between participants grouped by years since surgery and reported postoperative symptoms, the OSDI mean scores did approach significance (p = 0.088), suggesting that further research with a greater survey population is required.

INTRODUCTION: There are two main procedures responsible for correcting refractive error: laser-assisted in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). The most common postoperative complication of all laser vision correction (LVC) surgeries is keratoconjunctivitis sicca, or dry eye. In addition to physical irritation, dry eye can cause poor visual acuity and reduced quality of life. There are inconsistencies in the literature about which procedure results in higher rates of dry eye thus we explored the likelihood of a dry eye intervention within the first year after surgery. METHODS: Performing a retrospective chart review of all patients who underwent LVC procedures between 2009-2019 at a private Boston ophthalmology clinic, we were able to quantify the proportion of patients that required postoperative dry eye interventions within the 12 months following surgery. At this clinic, a dry eye intervention was defined as one of two treatments: punctal plug insertion or prescription medication (Restasis or Xiidra) use. RESULTS: A total of 11,175 LASIK eyes from 5,920 individuals, 1,549 LASEK eyes from 880 individuals, and 2,006 PRK eyes from 1,165 individuals were included in the analysis. Comparing the proportion of LASIK dry eye interventions to the proportion of PRK/LASEK dry eye interventions via a 2-sample z-test at an alpha level of significance of 0.05, yielded a z-value= 5.7 and a p-value= <0.0001 at a 95% CI (0.0102 - 0.0208). CONCLUSION: Our results suggest a greater incidence of postoperative dry eye interventions for PRK/LASEK patients compared to LASIK patients in the 12 months following LVC surgery. This study was limited in regards to both objective and subjective indicators of dryness; therefore future studies should attempt to be more comprehensive in evaluating postoperative dry eye. However, this study should help surgeons in the decision making process of which refractive eye surgery to recommend in order to reduce postoperative dry eye incidence and improve overall patient quality of life and satisfaction. / 2022-06-08T00:00:00Z