Effect of laser in situ keratomileusis on tear stability

Impact of Dietary Nutrients on the Prevalence of Dry Eye Syndrome among Korean Women Aged 40 and above: Evidence from the Korea National Health and Nutrition Examination Survey

This study aimed to assess the prevalence of dry eye syndrome among Korean women aged 40 and above and explore the correlation between the syndrome and daily dietary nutrient intake. We analyzed data from 92,888 female participants (mean age: 63.35 ± 8.86 years) from the 8th Korea National Health and Nutrition Examination Survey (KNHANES 2019). Dietary intake was evaluated using a personalized 24 h recall method for 21 nutrients, including macronutrients, macro- and micro-minerals, and both water- and fat-soluble vitamins. Associations between nutrient intake and dry eye syndrome were determined using odds ratios from multivariate logistic regression. We found a 7.7% prevalence of dry eye syndrome in the population studied. Intake of dietary fiber (adjusted OR: 0.72), protein (adjusted OR: 0.84), omega-3 fatty acids (adjusted OR: 0.90), water (adjusted OR: 0.76), calcium (adjusted OR: 0.82), phosphate (adjusted OR: 0.87), potassium (adjusted OR: 0.88), magnesium (adjusted OR: 0.87), vitamin A (adjusted OR: 0.78), vitamin C (adjusted OR: 0.73), and vitamin E (adjusted OR: 0.86) was inversely associated with dry eye syndrome prevalence (p < 0.0001 for all). Conversely, a higher intake of carbohydrates (adjusted OR: 1.23), sugar (adjusted OR: 1.30), fat (adjusted OR: 1.25), cholesterol (adjusted OR: 1.32), sodium (adjusted OR: 1.18), iron (adjusted OR: 1.28), and zinc (adjusted OR: 1.26) correlated with an increased risk (p < 0.0001 for all). No significant associations were found between the prevalence of dry eye syndrome and the intake of omega-6 fatty acids and vitamin D. Our study identified significant associations between specific dietary nutrients and the risk of dry eye syndrome among Korean women aged 40 and above. These findings suggest that dietary choices could influence the likelihood of developing dry eye syndrome, indicating a potential role for dietary intervention in its management. However, it is important to note that these observations are preliminary, and further research is necessary to confirm these relationships and explore their implications for dietary recommendations in dry eye syndrome prevention and management.

Efficacy of topical 0.05% cyclosporine A and 0.1% sodium hyaluronate in post-refractive surgery chronic dry eye patients with ocular pain

BACKGROUND

The management of post-refractive surgery dry eye disease (DED) can be challenging in clinical practice, and patients usually show an incomplete response to traditional artificial tears, especially when it is complicated with ocular pain. Therefore, we aim to investigate the efficacy of combined topical 0.05% cyclosporine A and 0.1% sodium hyaluronate treatment in post-refractive surgery DED patients with ocular pain unresponsive to traditional artificial tears.

METHODS

We enrolled 30 patients with post-refractive surgery DED with ocular pain who were unresponsive to traditional artificial tears. Topical 0.05% cyclosporine A and 0.1% sodium hyaluronate were used for 3 months. They were evaluated at baseline and 1 and 3 months for dry eye and ocular pain symptoms and objective parameters, including Numerical Rating Scale (NRS), Neuropathic Pain Symptom Inventory modified for the Eye (NPSI-Eye), tear break-up time (TBUT), Schirmer I test (SIt), corneal fluorescein staining (CFS), corneal sensitivity, and corneal nerve morphology. In addition, tear levels of inflammatory cytokines and neuropeptides were measured using the Luminex assay.

RESULTS

After 3 months of treatment, patients showed a statistically significant improvement in the ocular surface disease index (OSDI), TBUT, SIt, CFS, and corneal sensitivity (all P < 0.01) using linear mixed models. As for ocular pain parameters, the NRS and NPSI-Eye scores were significantly reduced (both P < 0.05) and positively correlated with the OSDI and CFS scores. Additionally, tear IL-1β, IL-6, and TNF-α levels were improved better than pre-treatment (P = 0.01, 0.03, 0.02, respectively).

CONCLUSION

In patients with post-refractive surgery DED with ocular pain, combined topical 0.05% cyclosporine A and 0.1% sodium hyaluronate treatment improved tear film stability, dry eye discomfort, and ocular pain, effectively controlling ocular inflammation.

TRIAL REGISTRATION

Registration number: NCT06043908.

Cationic nanoemulsion vs. 0.15% sodium hyaluronate artificial tears in the healing process following modern surface keratorefractive surgery

PURPOSE

The aim of this study was to investigate the influence of artificial tears containing either cationic nanoemulsion (CCN) or sodium hyaluronate artificial tears (SH) on early postoperative healing after modern surface refractive surgery.

MATERIALS AND METHODS

In this multicenter, prospective, double-masked, parallel-group (1:1), comparative study, 129 patients (n = 255 eyes) were randomized to receive CCN (n = 128) or SH (n = 127) as an adjuvant treatment after either transepithelial photorefractive keratectomy (transPRK) or Epi-Bowman keratectomy (EBK). The patients' perspectives were gathered using the Ocular Surface Disease Index (OSDI) questionnaire, and uncorrected (UCVA), and corrected (BCVA) visual acuity were assessed before and one week and one month after the procedure. In addition, corneal epithelization and subjective assessment of visual blur and eye irritation on drop instillation were assessed at one week postoperatively.

RESULTS

No statistically significant differences were found between two groups in age, spherical equivalent refractive error, UCVA, BCVA or OSDI scores before the procedure. There was also no difference between groups in UCVA one week and one month after the procedure. However, statistically significantly lower OSDI scores were found one week and one month after the procedure in the CCN group. Moreover, blurred vision after use of the eye drops was observed less frequently in the CCN group than in the SH group.

CONCLUSIONS

The CCN and SH groups had similar postoperative UCVA. However the significantly lower OSDI scores and less frequently blurred vision after application of the eye drops in the CCN group suggest better subjective outcomes in this group.

TFOS Lifestyle: Impact of contact lenses on the ocular surface

Several lifestyle choices made by contact lens wearers can have adverse consequences on ocular health. These include being non-adherent to contact lens care, sleeping in lenses, ill-advised purchasing options, not seeing an eyecare professional for regular aftercare visits, wearing lenses when feeling unwell, wearing lenses too soon after various forms of ophthalmic surgery, and wearing lenses when engaged in risky behaviors (e.g., when using tobacco, alcohol or recreational drugs). Those with a pre-existing compromised ocular surface may find that contact lens wear exacerbates ocular disease morbidity. Conversely, contact lenses may have various therapeutic benefits. The coronavirus disease-2019 (COVID-19) pandemic impinged upon the lifestyle of contact lens wearers, introducing challenges such as mask-associated dry eye, contact lens discomfort with increased use of digital devices, inadvertent exposure to hand sanitizers, and reduced use of lenses. Wearing contact lenses in challenging environments, such as in the presence of dust and noxious chemicals, or where there is the possibility of ocular trauma (e.g., sport or working with tools) can be problematic, although in some instances lenses can be protective. Contact lenses can be worn for sport, theatre, at high altitude, driving at night, in the military and in space, and special considerations are required when prescribing in such situations to ensure successful outcomes. A systematic review and meta-analysis, incorporated within the review, identified that the influence of lifestyle factors on soft contact lens dropout remains poorly understood, and is an area in need of further research. Overall, this report investigated lifestyle-related choices made by clinicians and contact lens wearers and discovered that when appropriate lifestyle choices are made, contact lens wear can enhance the quality of life of wearers.

Impact of Topical Cyclosporine-A or Topical Chloroquine on Post-LASIK Ocular Surface Stability - A Randomized Controlled Trial

PURPOSE

To compare effect of topical cyclosporine-A 0.05% (CsA) and chloroquine phosphate 0.03% (CHQ) as an adjunct to standard therapy in maintaining post-laser assisted in situ keratomileusis (LASIK) ocular surface stability.

METHODS

Randomized controlled trial on 100 eyes undergoing femtosecond-LASIK randomized into three groups: 33 eyes in Group I (Standard Treatment group), 34 eyes in Group II (CsA group) and 33 eyes in Group III (CHQ group). Standard treatment included topical moxifloxacin, topical prednisolone and carboxymethyl cellulose. Group II received topical CsA 0.05% twice daily for three months and group III received topical CHQ 0.03% twice daily for three months in addition to standard treatment. Primary outcome measure was change in ocular surface disease index (OSDI) at 6 months. Secondary outcome measures were tear break up time (TBUT), Schirmer-I score, tear film osmolarity, tear film MMP-9 and visual acuity. Follow-up was performed at postoperative 1, 3 and 6 months.

RESULTS

At 6 months, OSDI score, MMP-9, tear osmolarity, TBUT and Schirmer score were significantly better in both CsA and CHQ groups as compared with controls (p < 0.001). OSDI, Tear osmolarity, TBUT, MMP-9 levels were comparable in CsA and CHQ group (p > 0.05). In CsA group, tear film MMP-9 levels at 6 months were comparable to preoperative baseline (p = 0.09). There was no significant change in the Schirmer score from baseline in the CsA group; in addition, the Schirmer score was significantly better than the CHQ group at 6 months (p = 0.02). Visual acuity was comparable in all three groups. Adverse effects including burning sensation, stinging, pain and redness were reported by ten patients (CsA group- 3, CHQ group-7; p = 0.28).

CONCLUSION

Both CsA and CHQ are useful adjuncts to standard therapy in maintaining ocular surface stability after refractive surgery. Cyclosporine A has more potent and sustained anti-inflammatory effect with less ocular irritative effects.

Post-LASIK dry eye disease: A comprehensive review of management and current treatment options

Laser-assisted in situ keratomileusis (LASIK) is a unique corneal stromal laser ablation method that uses an excimer laser to reach beneath corneal dome-shaped tissues. In contrast, surface ablation methods, such as photorefractive keratectomy, include removing epithelium and cutting off the Bowman's layer and the stromal tissue of the anterior corneal surface. Dry eye disease (DED) is the most common complication after LASIK. DED is a typical multi-factor disorder of the tear function and ocular surface that occurs when the eyes fail to produce efficient or adequate volumes of tears to moisturize the eyes. DED influences quality of life and visual perception, as symptoms often interfere with daily activities such as reading, writing, or using video display monitors. Generally, DED brings about discomfort, symptoms of visual disturbance, focal or global tear film instability with possible harm to the ocular surface, the increased osmolarity of the tear film, and subacute inflammation of the ocular surface. Almost all patients develop a degree of dryness in the postoperative period. Detection of preoperative DED and committed examination and treatment in the preoperative period, and continuing treatments postoperatively lead to rapid healing, fewer complications, and improved visual outcomes. To improve patient comfort and surgical outcomes, early treatment is required. Therefore, in this study, we aim to comprehensively review studies on the management and current treatment options for post-LASIK DED.

Omega-3 polyunsaturated fatty acids and corneal nerve health: Current evidence and future directions

Corneal nerves play a key role in maintaining ocular surface integrity. Corneal nerve damage, from local or systemic conditions, can lead to ocular discomfort, pain, and, if poorly managed, neurotrophic keratopathy. Omega-3 polyunsaturated fatty acids (PUFAs) are essential dietary components that play a key role in neural development, maintenance, and function. Their potential application in modulating ocular and systemic inflammation has been widely reported. Omega-3 PUFAs and their metabolites also have neuroprotective properties and can confer benefit in neurodegenerative disease. Several preclinical studies have shown that topical administration of omega-3 PUFA-derived lipid mediators promote corneal nerve recovery following corneal surgery. Dietary omega-3 PUFA supplementation can also reduce corneal epithelial nerve loss and promote corneal nerve regeneration in diabetes. Omega-3 PUFAs and their lipid mediators thus show promise as therapeutic approaches to modulate corneal nerve health in ocular and systemic disease. This review discusses the role of dietary omega-3 PUFAs in maintaining ocular surface health and summarizes the possible applications of omega-3 PUFAs in the management of ocular and systemic conditions that cause corneal nerve damage. In examining the current evidence, this review also highlights relatively underexplored applications of omega-3 PUFAs in conferring neuroprotection and addresses their therapeutic potential in mediating corneal nerve regeneration.

Factors affecting the prevalence, severity, and characteristics of ocular surface pain

Introduction

Ocular surface pain has been traditionally lumped under the umbrella term "dry eye" (DE) but is now understood as its own entity and can occur in the absence or presence of tear dysfunction. Identifying patients at risk for the development of chronic ocular surface pain, and factors contributing to its severity are important in providing precision medicine to patients.

Areas covered

In this review, we discuss factors linked to the presence and severity of ocular surface pain, including eye related features, systemic characteristics, and environmental findings. We discuss corneal nerves, whose anatomic and functional integrity can be characterized through in vivo confocal microscopy images and testing of corneal sensitivity. We review systemic diseases that are co-morbid with ocular surface pain, including physical and mental health diagnoses. Finally, we identify environmental contributors, including air pollution, previous surgeries, and medications, associated with ocular surface pain.

Expert opinion

Intrinsic and extrinsic factors contribute to ocular surface pain and must be considered when evaluating an individual patient. These factors can inform the suspected etiology of the pain, and guide management decisions such as tear replacement or medications targeting nerve pain.

Early Outcomes of Two Treatment Modes of PresbyLASIK: Monocular vs. Micro-Monovision

PURPOSE

To report the visual, refractive and subjective outcomes of presbyLASIK for the correction of presbyopia.

METHODS

Monocular (20 eyes) or micro-monovision (12 eyes) presbyLASIK was performed on a total of 32 eyes in 16 patients (50% female, average age 55±4.6 years) using the Zeiss VisuMax 400Hz femtosecond and Schwind Amaris 1050RS excimer laser platform. Predictability, safety and efficacy were assessed and compared at 4-6 weeks, 3 months and 6 months. Results were considered significant if P < 0.05.

RESULTS

For monocular treatments, average postoperative spherical equivalent (SE) was 0.1±0.1 D and -0.86±0.5 D at 4-6 weeks postoperatively for distance and near eyes respectively; 90% eyes achieved SE ±1.0 D of the target. Postoperative binocular uncorrected distance (UDVA), intermediate (UIVA) and near visual acuity (UNVA) were -0.03±0.1 LogMAR (20/20), 0.09±0.26 LogMAR (N4) and 0.29±0.11 LogMAR (N6) respectively with 90% patients achieving binocular UDVA of 20/20 or better. For micro-monovision treatments, average postoperative SE was -0.33±0.51 D and -1.60±0.78 D at 4-6 weeks postoperatively for distance and near eyes respectively; 100% eyes achieved SE ±1.0 D of the target. Postoperative binocular UDVA, UIVA and UNVA were 0.05±0.16 LogMAR (20/20), -0.02±0.10 LogMAR (N3) and 0.23±0.08 LogMAR (N5) respectively with 67% patients achieving binocular UDVA of 20/20 or better.

CONCLUSION

Monocular and micro-monovision presbyLASIK are both effective options for the treatment of presbyopia. Monocular treatments are more likely to be well tolerated by patients who prefer to preserve exceptional distance vision, while micro-monovision treatments may be better suited to patients who can tolerate compromises in distance vision in order to attain greater intermediate vision function.

Alterations in the ocular surface and tear film following keratoplasty

The purpose of this study was to evaluate any alterations in the tear film and ocular surface beyond the early postoperative period following penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK). This cross-sectional, contralateral-eye study compared ocular surface and tear film parameters of eyes with a previous PK or DALK in one eye and no prior surgery in the contralateral eye. Overall, 14 (87.5%) participants underwent PK, and 2 (12.5%) underwent DALK using a mechanical dissection. The median time from surgery was 3.4 years (range 1.5 to 38.7 years). The indication for unilateral keratoplasty was keratoconus in 15 (94%) participants, and corneal scarring in 1 (6%) eye, secondary to microbial keratitis. Operated eyes exhibited poorer non-invasive tear film breakup time, lower corneal sensitivity, lower sub-basal nerve density and more severe fluorescein staining scores than unoperated fellow eyes (all Q < 0.05). There were no significant differences in tear film lipid layer quality, tear meniscus height, conjunctival hyperaemia, lissamine green staining score, or meibography grade between operated and fellow eyes (all Q ≥ 0.20). Higher corneal esthesiometry threshold (lower corneal sensitivity) was correlated with shorter non-invasive tear film breakup time (Spearman’s rho =  − 0.361, p = 0.04) and increased fluorescein staining score (Spearman’s rho = 0.417, p = 0.02). Keratoplasty can induce persistent changes in the ocular surface and tear film, including: increased fluorescein staining, decreased tear film breakup time, decreased corneal sub-basal nerve plexus density, and reduced corneal sensitivity.

The preoperative management of meibomian gland dysfunction prior to corneal refractive surgery

PURPOSE OF REVIEW

To describe the significance of meibomian gland dysfunction (MGD) in corneal refractive surgery and to describe available approaches to preoperative evaluation and treatment based on current research.

RECENT FINDINGS

There are several methods available for the evaluation and treatment of MGD. These are relevant for refractive surgeons to understand, as the presence of MGD preoperatively plays a role in the severity of MGD after corneal refractive surgery. Refractive surgery itself can exacerbate MGD. Treatment of MGD prior to surgery may have a meaningful impact on postoperative MGD.

SUMMARY

Surgeons should include meibomian gland assessment in the preoperative refractive evaluation and should treat MGD proactively prior to performing refractive surgery. Relevant information in this field is growing; additional prospectively designed studies are needed to further enhance our understanding.

The Efficient Regeneration of Corneal Nerves via Tunable Transmembrane Signaling Channels Using a Transparent Graphene-Based Corneal Stimulation Electrode

The efficient regeneration of corneal nerves is of limited success in the field of ophthalmology. This work reports the use of a non-invasive electrical stimulation technique that uses a transparent graphene-based corneal stimulation electrode and that can achieve efficient regeneration of corneal nerves. The corneal stimulation electrode is prepared using electroactive nitrogen-containing conducting polymers such as polyaniline functionalized graphene (PAG). This composite can carry a high capacitive current. It can be used to tune transmembrane signaling pathways including calcium channels and the MAPK signaling pathway. Tuning can lead to the efficient regeneration of corneal damaged nerves after the surgery of laser in-situ keratomileusis (LASIK). The composite and its application reported have the potential to provide a new way to treat nerve-related injuries.

Patients’ Awareness of the Ocular Side Effects of Isotretinoin Therapy: A Study From Saudi Arabia

Introduction

Isotretinoin is one of the most commonly prescribed drugs among dermatologists because it's used in the treatment of Acne vulgaris. Despite having an adequate safety profile, isotretinoin-related adverse events are common, with ocular manifestations being one of them. Although being generally mild, ophthalmologic manifestations associated with isotretinoin may cause significant ocular morbidity.

Objectives

The objective is to evaluate the awareness of the ocular side effects of isotretinoin treatment in patients with acne and to understand the treating physicians' practice of prescribing isotretinoin from the patient's point of view.

Method

A descriptive cross-sectional study was conducted on a Saudi Arabian population from June to September 2021. We used a self-administered questionnaire to collect data on drug dose, treatment duration, ocular adverse effects, patients' awareness, and patients' perception of treating physicians' practice.

Results

Of 1,157 responders, 452 (39.1%) consisted of participants who met the inclusion criteria, therefore they were enrolled in the study. Out of our responders, 308 (68.1%) were women. Approximately, 91.6% of participants had a dermatologist's prescription for isotretinoin. Eye dryness was the most commonly reported ocular adverse effect (83.4%). Blepharitis and conjunctivitis were the most commonly diagnosed complications after starting isotretinoin (5.4% for each).

Approximately, 71.2% participants were not advised to see an ophthalmologist for ophthalmological screening. Physicians asked only 78 (17.3%) respondents about a recent refractive surgery before starting isotretinoin or if they intended to undergo a refractive surgery in the next six months. Approximately, 57.5% participants were unaware of possible contact lens intolerance. Lubricant eye drops were prescribed to 305 (67.5%) respondents during isotretinoin treatment. Approximately, 36.7% participants were advised to consult their treating physicians if they had any serious ocular signs or symptoms.

Approximately, 67.9% participants reported their awareness of the ocular side effects of isotretinoin therapy. However, 236 (52.2%) participants responded that they were not provided with sufficient information on the ocular side effects of isotretinoin therapy.

Assessment of the correlation of the tear breakup time with quality of vision and dry eye symptoms after SMILE surgery

Purpose

It is well reported that dry eye symptoms can increase after many refractive surgery procedures. This study aims to provide a clinical understanding of the correlation of fluorescein tear film breakup time (FTBUT) with quality of vision (QoV) and dry eye symptoms following small incision lenticule extraction surgery (SMILE).

Methods

Patients electing to have SMILE surgery were subdivided into 2 groups: Group 1 included short preoperative FTBUTs of 3 to 6 seconds (s); Group 2 included long FTBUTs of ≥ 8 s. Uncorrected distance visual acuity, corrected distance visual acuity, manifest refraction, FTBUT, QoV and Ocular Surface Disease Index (OSDI) questionnaires were recorded 1 and 6 months postoperatively.

Results

Thirty-nine subjects were included in each group. There was no significant difference in visual outcomes between the 2 groups at both the 1- and 6-month postoperative assessments. FTBUT remained significantly lower in group 1. Oxford staining was initially higher for group 1 at 1 month (P = 0.007), but there was no significant difference at 6 months (P = 0.180). There was no significant difference in QoV or OSDI scores between the 2 groups at both postoperative visits.

Conclusions

Low preoperative FTBUT (3–6 s) does not appear to negatively affect postoperative visual outcomes or results in a greater likelihood of dry eye symptoms and poor ocular surface compared to eyes with a longer preoperative FTBUT. These results suggest that a low preoperative FTBUT does not necessarily increase the likelihood of poor visual acuity, dry eyes symptoms, or poor ocular surface outcomes following SMILE surgery.

Toric Implantable Collamer Lens for the Treatment of Myopic Astigmatism

Purpose

To report visual outcomes following surgical correction of myopic astigmatism with Visian Toric implantable collamer lens (ICL) (STAAR Surgical, Monrovia, CA, USA) at a single tertiary refractive center in the United States.

Patients and Methods

Toric ICL was implanted in 96 eyes (55 patients) with mean preoperative sphere of −8.98 ± 3.04 diopters (D) and cylinder of −2.67 ± 1.02 D from December 2018 to February 2021. Primary visual outcomes of efficacy, safety, stability, predictability of refractive correction, and astigmatic analysis were reported at three and twelve months postoperatively. Secondary subjective outcomes included patient-reported dry eye symptoms and glare/halos at postoperative visits. Other secondary outcomes were biometric data and postoperative vault over time.

Results

At three and twelve months, 75 and 46 eyes were evaluated, respectively. At twelve months, the mean manifest refraction spherical equivalent (MRSE) was −0.23 ± 0.47 D with 93% achieving within ±1.00 D of target refraction. The manifest refractive cylinder (MRC) at twelve months was −0.73 ± 0.51 D, with 86% within ±1.00 D of target. Uncorrected distance visual acuity (UDVA) was 20/20 or better in 74% of eyes at twelve months. No patients lost ≥2 lines of corrected distance visual acuity (CDVA) at twelve months. The mean angle of error was −0.9 ± 10.2° at three months and −1.6 ± 12.8° at twelve months. One patient required bilateral lens rotation, four patients underwent secondary enhancement with LASIK/PRK, and seven patients underwent postoperative limbal relaxing incisions.

Conclusion

This initial single-site experience finds Toric ICL implantation for myopic astigmatism to be safe and effective. Patients can achieve markedly improved UDVA in a single surgery with stable vision over time and minimal adverse subjective symptoms.

Neuropathic Corneal Pain Following LASIK Surgery: A Retrospective Case Series

Introduction

Transient dry eye symptoms have been reported following laser in situ keratomileusis (LASIK). Very rarely, patients may present with debilitating symptoms of dry eye syndrome (DES) with limited or no evidence of ocular surface disease. These patients are diagnosed with a form of DES known as neuropathic corneal pain (NCP).

Patients and Methods

This study is a retrospective medical record review of a case series of 18 patients who developed NCP post-LASIK over the years 1996–2021. All patients who developed severe ocular pain following LASIK consistent with NCP were included. Patients with severe ocular pain who had evidence of severe ocular surface disease or other ophthalmic etiology to explain their debilitating symptoms were not included.

Results

The average age of patients in our study was 39.5 years. The majority of our patients were female (72.2%) and of Caucasian ancestry (83.3%). The average onset of symptoms was 9.6 months post-LASIK. Patients had past medical histories significant for neuropsychiatric conditions (50%), functional pain syndromes (22.2%), autoimmune diseases (33.3%), and hypothyroidism (27.8%), and the occurrence of these was higher than the national prevalence of these diseases. Symptoms were consistent with the severity and characteristics defining NCP. Treatment was multimodal, involved topical and systemic therapies, and was unique to each patient. Overall, the majority of patients had clinical improvement in symptoms following treatment with regular follow-up.

Conclusion

Although rare, the 26-year prevalence of NCP post-LASIK in our study was roughly 1 in 900 cases. The mean time to onset after surgery was delayed at 9.6 months. Certain risk factors such as neuropsychiatric conditions, history of functional pain syndromes, history of autoimmune conditions, and hypothyroidism may predispose patients to the development of this condition. Patients benefited from proper diagnosis and a multimodal approach to treatment.

The 25th Anniversary of Laser Vision Correction in the United States

Laser Vision Correction (LVC) is an elective, self-pay and safe surgical procedure to correct myopia and hyperopia. Since FDA approval 25 years ago, there have been a progression of technological improvements leading to better outcomes and LVC is now one of the safest surgical procedures. With a potential pool of 50 million patients, 6000 trained ophthalmic surgeons regularly treating in over 1000 centers of which 65% are physician owned. Treatments remain low from an earlier peak of 1.4 million to less than 800,000 over last 10 years. The factors preventing patients undergoing surgery have not changed and include the cost of $2000 ± $1000 per eye and fear of laser surgery on their eyes. The latter is overcome by word of mouth referrals and positive social media messaging. In addition, press misinformation and lack of optometrists participating in co-management have not helped grow LVC procedures despite the positive results of the FDA’s Patient Reported Outcomes with LASIK studies known as PROWL. The surgery is quick, and patients can be “in and out” in less than two hours with a rapid recovery, minimal postoperative restrictions and within 24 hours have 20/20 vision. Volume and price drives center and physician profitability with a scheduling capacity of two to four patients’ treatments per hour. Laser vision correction and especially LASIK, remains the treatment of choice for myopic and hyperopic patients wanting to remove their dependency on glasses and contact lenses.

Meibomian Gland Morphology Among Patients Presenting for Refractive Surgery Evaluation

Purpose

To report the prevalence of meibomian gland atrophy and gland tortuosity in patients presenting for refractive surgery evaluation.

Methods

Cross-sectional study of consecutive patients presenting for refractive surgery evaluation at the Duke Eye Center from December 2018 through January 2020. All patients underwent clinical examination and meibography imaging (Lippiview II, Johnson and Johnson Vision, CA) of the lower eyelids bilaterally. Images were graded by a masked rater using a previously validated 5-point meiboscale (0–4) for gland atrophy and 3-point scale for gland tortuosity (0–2). Lipid layer thickness and partial blinks were also recorded.

Results

One hundred and twenty patients (49 male) aged 21 to 62 years (mean 35.2 ± 9.2 years) were reviewed. The mean meiboscale was 1.1 ± 1.0 and the mean tortuosity score was 1.0 ± 0.7. Among all patients, 72.5% (n = 87) had any evidence of meibomian gland atrophy (meiboscale >0) and 69.2% (n = 83) had any evidence of meibomian gland tortuosity (tortuosity grade ≥1). The majority of patients (n = 52) with gland atrophy had mild gland atrophy (meiboscale = 1). The mean meiboscale was 0.89 ±0.79 and 1.38 ±1.07 for those <35 years and >/= 35 years old, respectively (p = 0.01). There was a moderate positive relationship between meiboscale and tortuosity (Spearman’s rho 0.3829, p <0.001).

Conclusion

Meibomian gland atrophy is a common occurrence in patients presenting for refractive surgery evaluation. Clinicians should consider incorporating meibography as part of refractive surgery evaluation, and proactively treat meibomian gland disease given the known association between meibomian gland dysfunction, dry eye disease, and the potential for suboptimal post-operative outcomes.

Post laser-assisted in-situ keratomileusis dry eye disease and temporary punctal plugs

PURPOSE

The aim of this study was to compare the incidence of post laser in situ keratomileusis (LASIK) dry eye with and without intraoperative extended duration temporary punctal plug placement.

METHODS

This retrospective study included myopicastigmatic eyes without a preoperative diagnosis of dry eye disease that underwent LASIK surgery between January 2017, and March 2018. Patients who received punctal plugs during surgery in addition to usual postoperative care were compared to a control group who received usual postoperative care alone. Visual acuity, safety and efficacy indices, as well as predictability and presence of dry eye disease were assessed 3-6 months after surgery.

RESULTS

A total of 345 eyes of 345 patients were included, 172 eyes received punctal plugs and 173 did not. The mean age was 30.4 ± 10 years (range: 17-60 years) and 46.1% (N = 159) were female. Both groups were similar in terms of preoperative parameters, including age, gender, spherical equivalent, pachymetry or contact lens use. Patients treated with punctal plugs had significantly less postoperative dry eye complaints (N = 37 vs. 58, 21.5% vs. 34.1% respectively, P = 0.001). Patients treated with plugs that did develop dry eye disease did so later (51.2 ± 77.64 days' vs. 20.78 ± 26.9 days, P = 0.009). Postoperative visual acuities were similar between groups (P > 0.05) at all postoperative follow-up visits as were safety (0.95 ± 0.16 vs. 0.99 ± 0.09, P = 0.30) and efficacy (1.01 ± 0.13 vs. 1.00 ± 0.11, P = 0.52) indices.

CONCLUSION

Preventative temporary punctal plug placement during LASIK appears to reduce dry eye disease in the short term, without affecting visual acuity outcomes.

Impact of corneal refractive surgery on the precorneal tear film

Corneal refractive surgeries are one of the commonly performed procedures for correction of refractive errors. Tear film abnormality is the most common postoperative complication of corneal refractive surgeries. Consequently, these procedures represent a clinically significant cause of dry eye disease. The mechanisms which lead to dry eye disease include corneal sensory nerve dysfunction, ocular surface desiccation, glandular apoptosis and ocular surface inflammation. Although transient tear film abnormalities occur in almost all patients following surgery, patients with pre-existing dry eye symptoms or dry eye disease are at significant risk of developing more severe or long-term ocular surface disease. As such, careful patient selection and preoperative evaluation is essential to ensuring successful surgical outcomes. This is particularly important with LASIK which has the strongest association with dry eye disease. Appropriate surface lubrication and anti-inflammatory therapy remains the cornerstone treatment. Timely and effective management is important to facilitate visual rehabilitation and reduce the risk of secondary complications. In this review we describe the causes, pathophysiology, risk factors, manifestations, and management of tear film dysfunction and dry eye disease following corneal refractive surgery.

Cataract surgery and dry eye disease: A review

AIM

To review published literature concerning cataract surgery and dry eye disease (DED).

METHODS

A search was undertaken using the following: PubMed (all years), Web of Science (all years), Ovid MEDLINE(R) (1946 to 12 December 2019), Ovid MEDLINE(R) Daily Update 10 December 2019, MEDLINE and MEDLINE non-indexed items, Embase (1974-2019, week 49), Ovid MEDLINE (R) and Epub Ahead of Print, In-Process and Other Non-Indexed Citations and Daily (1946 to 12 December 2019), CENTRAL (including Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 12 of 12 December 2019), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included 'cataract surgery', 'phacoemulsification' and 'cataract extraction', combined with 'dry eyes' and 'ocular surface'. Relevant in-article references not returned in our searches were also considered.

RESULTS

Publications identified included systematic reviews, meta-analysis, randomized controlled trials, cohort studies, case series and laboratory-based studies. Published data highlighting the burden of DED both prior and following cataract surgery were reviewed as well as studies highlighting the effects of cataract surgery on the ocular surface, intra-operative measures to reduce deleterious effects on the ocular surface and current evidence on the management options of post-operative DED.

CONCLUSIONS

DED is common and can be exacerbated by cataract surgery. Ophthalmologists need to assess for pre-existing DED and instigate treatment before surgery; be aware of reduced accuracy of measurements for surgical planning in the presence of DED; limit intra-operative surgical factors damaging to the ocular surface; and consider management to reduce DED post-operatively.

Acupuncture for dry eye syndrome after refractive surgery: A randomized controlled pilot trial

Background

Dry eye syndrome is the most common complication of refractive surgery. Acupuncture is widely used for the treatment of ophthalmologic diseases, but to date, few have explored the effects of acupuncture for the treatment of this condition following refractive surgery. The objective of this study is to assess the feasibility of a study design for evaluating the effectiveness of acupuncture treatment along with usual care compared with usual care only for dry eye syndrome after refractive surgery.

Methods

A total of 18 patients with dry eye syndrome occurring after refractive surgery participated in this study. For 4 weeks, the acupuncture plus usual care and usual care only groups received treatment three times a week. A series of assessments, namely the ocular surface disease index (OSDI), visual analog scale for ocular discomfort, quality of life, tear film break-up time, Schirmer 1 test, and fluorescein-stained corneal-surface photography, along with other general assessments were carried out.

Results

Although preliminary, changes in OSDI from the baseline values were significantly different between the two groups at week 5 (p = 0.0003). There was a significant difference in the trends of OSDI changes between the acupuncture plus usual care and the usual care only groups (p = 0.0039). No serious adverse events were reported during the study.

Conclusion

Four weeks of acupuncture treatment in addition to usual care is a feasible treatment for dry eye syndrome after refractive surgery. A full-scale randomized controlled trial is needed to confirm the clinical effectiveness of acupuncture.

A Multicenter Study of the Prevalence of Dry Eye Disease in Chinese Refractive Surgery Candidates

OBJECTIVE

The aim of this study was to determine the prevalence of preoperative dry eye disease and evaluate tear film function in refractive surgery candidates in China.

METHODS

In this prospective noninterventional cross-sectional study, refractive surgical candidates from 13 preselected eye hospitals in China were recruited from July 2015 to February 2016. Patient histories, subjective symptoms, tear film breakup time (TBUT), ocular surface fluorescein staining, and Schirmer I tests (SIT), were assessed to conduct subgroup analysis.

RESULTS

A total of 1,849 patients were recruited, 41.4% were diagnosed with dry eye disease (766/1,849) and 44.9% (830/1,849) of subjects had a positive history of contact lens (CL) wear. The overall mean TBUT and SIT values were 7.3 ± 3.7 s and 15.2 ± 8.8 mm, respectively. The total prevalence of ocular surface fluorescein staining was 23.46% (422/1,849); 44.62% of patients had TBUT <5 s and 23.20% of patients had SIT <5 mm. CL wearers were observed to have a higher prevalence of dry eye than non-CL wearers (54.1 vs. 35.2%, OR = 2.17, 95% CI: 1.77-2.65).

CONCLUSIONS

In this study, the most common abnormal finding in dry eye disease was tear film instability. A high proportion of refractive surgery candidates have preexisting dry eye disease and a history of CL wear prior to surgery. Careful attention should be given to the evaluation of preoperative dry eye in refractive surgery candidates.

Clinical and tear cytokine profiles after advanced surface ablation refractive surgery: A six-month follow-up

Neuropathic dry eye is one of the most frequently seen complications after corneal refractive surgery, however, its incidence decreases in a significant manner along the first six months postoperative, reaching between 10 and 45% incidence. However, little is known on the inflammatory status of the ocular surface during this recovery process. We aim to analyze the clinical and tear molecule concentration changes along six months after advanced surface ablation for myopia correction, in a prospective study including 18 eyes of 18 subjects who bilaterally underwent advanced surface ablation corneal refractive surgery. Clinical variables (uncorrected distance visual acuity, symptoms, conjunctival hyperemia, tear osmolarity, tear stability, corneal fluorescein staining, conjunctival lissamine staining, Schirmer test, and corneal esthesiometry) and a panel of 23 pro and anti-inflammatory cytokines/chemokines concentration in tears preoperatively and at 1, 3 and 6 months postoperatively were evaluated. We found that uncorrected distance visual acuity improved significantly from baseline at 1-month visit, symptoms improved and tear osmolarity decreased significantly from baseline at 3-month visit and there was a decrease in mechanical corneal threshold between 1-month and 3- and 6-month visits. Regarding tear molecules, IL-4, IL-5, IL-6, IL-13, IL-17A, and IFN-γ tear levels were significantly increased at all the three visits, compared to preoperative levels at V0; IL-2 and VEGF were also significantly increased at 1-month and 6-month visits, but not at 3-month visit, whereas IL-9 IL-10 and IL-12 were only significantly increased at 6-month visit. Although we found that there is a recovery in clinical variables at 6 months postoperatively (i.e. neuropathic dry eye was not developed in the sample), ocular surface homeostasis is not completely restored, as it can be seen by the changes in concentration of some pro and anti-inflammatory molecules measured in tears.

Risk factors for early flap misalignment following microkeratome-assisted laser in situ keratomileusis: A retrospective large database analysis

PURPOSE

To determine factors associated with early flap misalignment following microkeratome-assisted laser in situ keratomileusis.

MATERIALS AND METHODS

This retrospective study included the right eyes of consecutive patients who underwent laser in situ keratomileusis procedure between 2005 and 2016 at Care-Vision Laser Centers, Tel-Aviv, Israel. Patients were divided into two groups according to whether or not they subsequently developed early flap misalignment.

RESULTS

A total of 14,582 eyes (mean age of patients: 32.4 ± 10.3 years) were included. Post-laser in situ keratomileusis early flap misalignment developed in 158 eyes (1.1%). Misalignment was more frequent during the spring (32.3% vs 22.8%, p = 0.003) and in a higher operating room temperature (23.34 ± 1.06 vs 22.98 ± 1.26, p < 0.001). In addition, in the misalignment group, there was a higher rate with the of use of the a Moria M2 microkeratome (rather than sub-Bowman's keratomileusis microkeratome) head (55.2% vs 40.5%, respectively, p < 0.001). In a multivariable analysis adjusted for surgeon and year of surgery, high operating room temperature (odds ratio = 1.22, p = 0.006), treatment zone of 9.0 mm (as opposed to smaller treatment zones, odds ratio = 1.54, p = 0.04), and springtime (odds ratio = 1.58, p = 0.02) were associated with flap misalignment. There was a significant difference in misalignment rates between surgeons (p = 0.02).

CONCLUSION

This study found that larger treatment zones, higher operating room temperature, operating during the spring, and the use of Moria M2 microkeratome were associated with increased flap misalignment rates. The association with operating room temperature and seasonal variation is of interest and merits further research.

Effects of flap diameter on dry eye parameters and corneal sensation after femtosecond laser-assisted LASIK

PURPOSE:

Although femtosecond laser-assisted LASIK (laser-assisted in situ keratomileusis). provides a controllable flap size than a mechanical microkeratome, patients still experience dry eye symptoms after LASIK. The purpose of this study is to investigate the effects of different flap sizes on postoperative dry eye syndrome and corneal sensitivity.

PATIENTS AND METHODS:

This is a retrospective comparative study. Fifty-seven consecutive patients (113 eyes) who underwent myopic femtosecond laser-assisted LASIK treatment were recruited. Basic Schirmer's test value, tear breakup time (TBUT), corneal fluorescein staining scores, conjunctival rose bengal staining scores, and corneal sensitivity were measured before surgery, at postoperative 1, 3, and 6 months follow-up.

RESULTS:

When the eyes were grouped by flap diameter sizes (8.7 mm as the cutoff value), there were no significant differences in terms of corneal sensitivity and all dry eye parameters investigated at any time points between the large or small flap diameter groups. However, when the eyes were grouped by the ratio of flap diameter/horizontal corneal white-to-white distance (0.756 as the cutoff value), the larger ratio group showed decreased basic Schirmer's test (7.52 ± 4.43 mm) than the smaller group (12.15 ± 8.14) at 3 months (P = 0.006). Moreover, the group that had larger flap/corneal diameter ratio showed shorter TBUT (4.20 ± 1.73 s) than the smaller group (5.67 ± 1.90 s) at 6 months postoperatively (P = 0.011).

CONCLUSIONS:

LASIK-related dry eye syndrome was associated with flap/corneal diameter ratio, and surgeons should keep this effect in mind when customizing the cornea flap sizes for dry eye patients during LASIK.

Should I Get LASIK If I'm Breastfeeding?

Changes in keratometric values and refraction can occur during pregnancy. For this reason, changing a patient's refractive prescription or undergoing corneal refractive surgery is not recommended during pregnancy. However, the extent to which these corneal changes persist during lactation is not as well reported. Pregnancy and lactation lead to hormonal changes that affect the corneal structure. LASIK, or other types of refractive surgery, is not recommended until all of the following conditions are met: cessation of lactation, the return of regular menses, and a return to pre-pregnancy refraction. Additionally, patients should be cautioned that refractive regression may occur if they become pregnant within 1 year of LASIK. FUNDING: Research to Prevent Blindness, NY, USA.

Dry Eye After LASIK

Post-LASIK dry eye is the most common postoperative dry eye after ophthalmic surgeries. The clinical signs of post-LASIK dry eye include positive vital staining of the ocular surface, decreased tear breakup time and Schirmer test values, reduced corneal sensitivity, and decreased functional visual acuity. The symptoms and signs usually last for about 1 month after LASIK. A small number of patients continue to experience symptoms more than 1 year postoperatively. It has been suggested that the loss of corneal innervation caused by flap-making is the major cause, affecting the corneal-lacrimal gland, corneal-blinking, and blinking-meibomian gland reflexes, resulting in decreased aqueous and lipid tear secretion and mucin expression. A new type of corneal refractive surgery, SMILE, which has less impact on corneal nerves, induces less postoperative dry eye, supporting the association between corneal denervation and postoperative dry eye. As LASIK enhancement by flap-lifting induces fewer dry eye symptoms and signs than initial surgery, factors other than neurotrophic effects may be involved in the mechanisms of post-LASIK dry eye. Post-LASIK ocular surface pain is a type of postoperative chronic pain and discomfort, and is thought to be a different clinical entity from dry eye, possibly induced by abnormal reinnervation or neural sensitization of peripheral nerves and the central nervous system after LASIK. Treatments include tear supplements, anti-inflammatory agents, meibomian gland dysfunction management, ointment and eye patches, punctal plugs, and autologous serum eye drops. For patients with preoperative dry eye, careful patient selection, and preoperative ocular surface management are mandatory.

Patient satisfaction and self-reported dry eye symptoms in hyperopic patients treated with femtosecond laser in situ keratomileusis

Purpose

To study self-reported patient satisfaction and dry eye symptoms in hyperopic correction with femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

Patients and methods

Ninety-eight eyes (53 patients) were treated with FS-LASIK for hyperopia. Patients’ self-reported dry eye symptoms and satisfaction with near and far vision were graded on the visual analog scale (VAS) preoperatively and 1 month postoperatively.

Results

Ninety-one percent of the eyes with the plano target (54 eyes) achieved an uncorrected distance visual acuity of 20/20 or better. Predictability, defined as spherical equivalent refraction within ±0.5 D of target, was 88% of all eyes. None of the eyes lost two or more Snellen lines of corrected distance visual acuity. There was no significant change in the self-reported dry eye sensation (VAS score from 2.7±2.0 to 2.8±2.0; P=0.66). In 44 monovision patients, satisfaction with both far vision (from 71.2±19.8 to 89.2±8.7; P<0.0001) and near vision (from 51.7±26.2 to 89.3±13.2; P<0.0001) increased significantly. In nine emmetropic patients, satisfaction with neither far vision nor near vision was significantly improved, although there was a clear tendency (from 73.7±23.7 to 86.9±15.3; P=0.22, and from 58.9±29.1 to 81.6±17.4; P=0.11, respectively). In the monovision patient group, far vision satisfaction decreased when dry eye symptoms increased. Monovision patients, as predicted, were more satisfied with their near vision, when postoperative spherical equivalent from target was on the myopic side.

Conclusion

FS-LASIK correction of hyperopia significantly improved patient satisfaction with both near and far vision in monovision patients. Hyperopic patients had no significant changes in postoperative dry eye symptoms compared to preoperative values.

[Prevalence and severity of dry eye syndrome in myopic candidates for laser in situ keratomileusis]

PURPOSE

To assess the prevalence and severity of dry eye syndrome (DES) in patients with myopia being evaluated for laser in situ keratomileusis (LASIK).

MATERIAL AND METHODS

The prospective, non-interventional, cross-sectional study involving 9 Russian ophthalmic centers included 400 patients with myopia (aged 29.7 years in average). Among them, 145 (36.2%) wore contact lenses, and 81 (20.2%) used locally administered drugs for treatment of DES. The examination included Shirmer I test, tear film break-up test (TBUT), staining with lissamine green and fluorescein (Oxford scale), Ocular Surface Disease Index (OSDI) questionnaire, and classification of the disease according to dry eye workshop (DEWS).

RESULTS

Average Shirmer test result was 15.2 mm; 36.5% of patients had signs of tear deficiency (Shirmer test ≤10 mm). Average TBUT was 11.7 seconds; the tear film of 10.1% of patients was unstable (TBUT <5 seconds). Lissamine green staining was classified as insignificant or higher (degree ≥I) in 62.3% of patients and mild or higher (degree ≥II) - in 22.8%. Mean score of the OSDI questionnaire was 20.4 indicating mild vision impairment. Dry eye severity according to DEWS classification was mild/episodic in 66.2%, moderate - in 29.5%, and severe - in 4.3% of patients. No clear correlation was evident between the Schirmer/TBUT scores and the lissamine green/OSDI scores.

CONCLUSION

The prevalence of dry eye in this population was estimated at approximately 10% to 40% (based on clinical signs) and 40% to 55% (based on symptoms); dry-eye severity was predominantly mild/episodic. The proportion of patients requiring dry-eye therapy (based on OSDI and DEWS severity findings) was almost 2 times higher than the proportion receiving treatment.

Five Misconceptions Related to Punctal Plugs in Dry Eye Management

Punctal plugs are an effective treatment option for patients with aqueous-deficient dry eye refractory to topical medications. However, punctal plugs are not commonly used in clinical practice mainly because of various misconceptions, rather than clinical complications. We analyzed previous studies and present 5 misconceptions related to punctal plugs. The first and most important misconception is that ocular surface inflammation should be sufficiently controlled before punctal plug insertion. However, it is unclear how ocular surface inflammation can be sufficiently controlled in patients refractory to conventional topical medications. The second misconception is that silicone punctal plugs are made of nonabsorbable materials and, therefore, permanent. In fact, silicone plugs are reversible and can be easily removed if necessary. Therefore, depending on the specific type, nonabsorbable plugs may be classified as reversible or permanent. The third misconception is that punctal plugs disrupt normal tear drainage. However, punctal plugs maintain natural tears on the ocular surface for extended periods and reduce the frequency of artificial tear use. The fourth is that all punctal and canalicular plugs have similar effects. The efficacy and complication rates differ depending on plug types. The fifth misconception about punctal plugs is that they are effective only in aqueous-deficient dry eye disease. Many studies have reported that plugs are effective in a variety of ocular diseases and conditions. Understanding these 5 misconceptions may provide an opportunity to rethink the use of silicone punctal plugs in clinical practice.

Effects of femtosecond laser-assisted cataract surgery on dry eye

The aim of this study was to investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on tear film and ocular surface function. Patients with age-related cataract who underwent phacoemulsification (phaco) in Air Force Aviation Medicine Research Institute Affiliation Hospital from January 2016 to December 2016 were randomly divided into two groups. Patients in experimental group (n=123, 150 eyes) received FLACS, while patients in phaco group (n=110, 150 eyes) underwent conventional coaxial micro-incision phaco and were implanted with foldable intraocular lens (IOL). Our results showed that there were no statistically significant differences in general conditions between the two groups. Ocular surface disease index (OSDI) and corneal fluorescein staining (CFS) scores of patients in both groups after operation were significantly increased compared with those before operation, but breakup time (BUT) and Schirmer's I test scores decreased significantly at 1 week after operation compared with those before operation and basically returned to preoperative baseline levels at 3 months after operation. CFS scores and OSDI in the FLACS group at 1 day and 1 week after operation were increased more significantly than those in the phaco group, but there were no statistically significant differences at 3 months after operation. The above results showed that the effect on ocular surface function in the FLACS group after operation was greater than that in the phaco group, and the dry eye symptoms in the FLACS group were more obvious after operation. Both FLACS and conventional phaco have certain effects on the ocular surface function of patients, and there are statistically significant differences only in the early stage. FLACS has greater effects on CFS and dry eye symptoms.

Uncorrected visual acuity, postoperative astigmatism, and dry eye symptoms are major determinants of patient satisfaction: a comparative, real-life study of femtosecond laser in situ keratomileusis and small incision lenticule extraction for myopia

Purpose

To compare factors affecting patient satisfaction after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) for myopia in the real-life situation study.

Methods

The SMILE group included 100 eyes (51 patients) and the FS-LASIK group 200 eyes (102 patients). In addition to clinical examination, dry eye symptoms and patient satisfaction with far and near vision were reported and graded on the visual analog scale preoperatively and one month after the operation. Case–control pairs were selected for the SMILE patients from FS-LASIK-treated patients to ensure the homogeneity in spherical equivalent refraction, preoperative dry eye, and visual satisfaction.

Results

Eighty percent of SMILE eyes and 83% of FS-LASIK eyes achieved an uncorrected distance visual acuity of 20/20 or better. Predictability (±0.5 D of mean target spherical equivalent refraction) was 91% in SMILE and 93.5% in FS-LASIK. No eyes lost two or more Snellen lines of corrected distance visual acuity. Based on case–control pairs, dry eye symptoms remained the same after one month in the FS-LASIK-treated eyes (P=0.87) but decreased in the SMILE-treated eyes (P=0.01) compared with the preoperative situation. Patient satisfaction with far vision improved significantly in both groups (P<0.001), but satisfaction with near vision improved significantly only in FS-LASIK (P<0.001) and not in SMILE (P=0.58). There was more postoperative astigmatism in SMILE in comparison with FS-LASIK (P=0.002).

Conclusions

In a real-life situation, patients with preoperative dry eye experience were often directed to the SMILE operation, which resulted in beneficial decrease in their dry eye symptoms. Patient satisfaction with far vision decreased with increasing dry eye symptoms and postoperative astigmatism in both SMILE- and FS-LASIK-treated emmetropic patients. Safety, efficacy, and predictability were comparable in both treatments.

Tear meniscus evaluation after microkeratome laser in situ keratomileusis, femtosecond laser and femtosmile laser techniques using anterior segment optical coherence tomography

Purpose

The purpose of this study was to compare the effects of three different corneal refractive surgeries: microkeratome laser in situ keratomileusis (LASIK), femtosecond laser in situ keratomileusis (FS-LASIK) and femtosecond small incision lenticule extraction (FS-SMILE) on 6-month postoperative stability of tear film to provide a basis for selection of operative procedures.

Patients and methods

This is a prospective, randomized, comparative study that included 90 eyes of three equal groups of patients. Each group was subjected to a different laser technique: LASIK, FS-LASIK and FS-SMILE. Using anterior segment spectral domain optical coherence tomography (AS-SD-OCT), the lower tear meniscus parameters were measured preoperatively and 1 week, 1 month, 3 months and 6 months postoperatively. Changes were studied and compared.

Results

There was a statistically significant difference in tear meniscus height (TMH) between FS-SMILE and FS-LASIK in the first week (P = 0.003) and first month (P = 0.002) with no statistically significant difference between both techniques at 3 and 6 months postoperatively. In FS-SMILE, TMH returned to 95% of its preoperative level after 1 month. There was no statistically significant difference in TMH between FS-LASIK and microkeratome LASIK techniques after 1 week and 1 month, but there was a statistically significant difference between both techniques in 3 months (P = 0.019) and 6 months (P = 0.032). Tear meniscus area (TMA) showed no statistically significant difference between FS-SMILE and FS-LASIK at all points of follow-up, but there was a statistically significant difference between both techniques and microkeratome LASIK (all P < 0.05). Microkeratome LASIK parameters failed to reach the preoperative level till 6 months.

Conclusion

Early recovery of the lower TMH can be achieved as early as 1 month post-operatively with the FS-SMILE technique compared to FS-LASIK and microkeratome LASIK techniques.

Medico-legal aspects of corneal refractive laser eye surgery

It is estimated that over 40 million people have had laser vision correction worldwide since 1991. Laser-assisted subepithelial keratomileusis is commonplace in the UK in high street chains and from more bespoke suppliers. The standards around this treatment have always been regulated by the General Medical Council (GMC), but litigation cases have been common. The recent GMC guidance for cosmetic procedures and subsequent guidelines by the Royal College of Ophthalmologists cover advertising, facility regulations, equipment, consent and surgeon training which should improve industry practices and deliver improved patient safety standards.

Topical Osmoprotectant for the Management of Postrefractive Surgery-Induced Dry Eye Symptoms: A Randomised Controlled Double-Blind Trial

Background

Dry eye disease (DED) is one of the most common complications following refractive surgery.

Purpose

Evaluate the efficacy of an osmoprotective eye drop (Optive®) for the management of induced DED in refractive surgery patients.

Design

Double-masked randomised controlled trial.

Methods

Twenty-two refractive surgery patients oriented to apply FreshTears (FT; n = 13) or Optive (Op; n = 9), topically, QID, for 3 months. Eye exams were performed before surgery (T0) and 1-month (T1) and 3-month (T3) follow-up and consisted of tear film osmolarity, Schirmer 1 test, tear film breakup time (TBUT), fluorescein staining, and ocular surface disease index (OSDI) and patient symptoms questionnaires.

Main Outcome Measures

Pain and osmolarity.

Results

Pain increased significantly for FT at T3 (p < 0.05). A reduction in osmolarity was observed at T1 and T3 for Op group (p < 0.01) and at T3 for FT group (p < 0.05). TBUT showed a decrease between T0 and T1 for FT (p < 0.05). Schirmer 1 values increased significantly for Op in T1.

Conclusions

Op was superior to FT in regard to pain, osmolarity, TBUT, and Schirmer 1. Osmoprotectant solutes, such as L-carnitine, could attenuate inflammation and secondary DED. Osmoprotective lubricants can be effectively applied for the prevention of refractive surgery-related dry eye symptoms and signs.

Dry Eye Post-Laser-Assisted In Situ Keratomileusis: Major Review and Latest Updates

Dry eye is one of the most common complications occurring after laser-assisted in situ keratomileusis (LASIK), with virtually all patients experiencing some degree of postoperative dry eye symptoms. Enhanced understanding of the pathophysiology and mechanism of dry eye development in addition to preoperative screening of patients who are prone to dry eye is essential for better patient satisfaction and for improving short-term visual outcome postoperatively. This article reviews the latest studies published on LASIK-associated dry eye, including epidemiology, pathophysiology, risk factors, preoperative assessment, and management.

Dry eye syndrome: developments and lifitegrast in perspective

Dry eye (DE) is a chronic ocular condition with high prevalence and morbidity. It has a complex pathophysiology and is multifactorial in nature. Chronic ocular surface inflammation has emerged as a key component of DE that is capable of perpetuating ocular surface damage and leading to symptoms of ocular pain, discomfort, and visual phenomena. It begins with stress to the ocular surface leading to the production of proinflammatory mediators that induce maturation of resident antigen-presenting cells which then migrate to the lymph nodes to activate CD4 T cells. The specific antigen(s) targeted by these pathogenic CD4⁺ T cells remains unknown. Two emerging theories include self-antigens by autoreactive CD4 T cells or harmless exogenous antigens in the setting of mucosal immunotolerance loss. These CD4 T cells migrate to the ocular surface causing additional inflammation and damage. Lifitegrast is the second topical anti-inflammatory agent to be approved by the US Food and Drug Administration for the treatment of DE and the first to show improvement in DE symptoms. Lifitegrast works by blocking the interaction between intercellular adhesion molecule-1 and lymphocyte functional associated antigen-1, which has been shown to be critical for the migration of antigen-presenting cells to the lymph nodes as well as CD4⁺ T cell activation and migration to the ocular surface. In four large multicenter, randomized controlled trials, lifitegrast has proven to be effective in controlling both the signs and symptoms of DE with minimal side effects. Further research should include comparative and combination studies with other anti-inflammatory therapies used for DE.

Autologous Platelet-Rich Plasma Eye Drops for the Treatment of Post-LASIK Chronic Ocular Surface Syndrome

Purpose

To evaluate the efficacy of autologous platelet-rich plasma (E-PRP) eye drops for the treatment of chronic ocular surface syndrome (OSS) following laser in situ keratomileusis (LASIK).

Methods

This prospective interventional consecutive clinical study include 156 eyes of 80 patients affected by post-LASIK chronic OSS who were treated with autologous E-PRP 6 times a day as monotherapy for 6 weeks.

Results

Dry eye symptoms improved in 85% of the cases. A decrease in at least one quadrant to total disappearance on CFS was observed in 89.6% of the patients who had positive CFS before treatment. Three eyes presented severe punctate keratitis (1.9%) at baseline, all of which healed completely. Conjunctival hyperemia improved in 93.3% of the patients with previous signs of ocular surface inflammation. There was a significant improvement in logMAR CDVA from 0.14 ± 0.19 to 0.06 ± 0.12 (p = 0.000), and 74 (71.4%) eyes improved at least 1 line in CDVA.

Conclusion

Monotherapy with autologous E-PRP is a well-tolerated, safe, and effective treatment for the management of post-LASIK ocular surface syndrome.

Precis

Monotherapy with autologous platelet-rich plasma eye drops has been shown to be an adequate option for the treatment of post-LASIK chronic ocular surface syndrome. This trial is registered with NCT03322917.

Effectiveness of an Eyelid Thermal Pulsation Procedure to Treat Recalcitrant Dry Eye Symptoms After Laser Vision Correction

PURPOSE

To provide an initial retrospective evaluation of the effectiveness of a thermal pulsation system to treat intractable patient-reported dye eye symptoms following laser vision correction.

METHODS

A total of 109 eyes of 57 patients underwent thermal pulsation therapy (LipiFlow; TearScience, Morrisville, NC) for the treatment of dry eye symptoms following laser vision correction. A standardized dry eye questionnaire, the Standard Patient Evaluation of Eye Dryness (SPEED II), was administered to all patients before and after thermal pulsation therapy. The primary outcome was patient-reported dry eye symptoms as measured by this questionnaire.

RESULTS

The mean patient age was 49 years (interquartile range [IQR]: 38 to 60), 70% were female, and the primary refractive procedure was LASIK (n = 91, 83%) or photorefractive keratectomy (PRK) (n = 18, 17%). Patients underwent thermal pulsation therapy at a mean of 40.5 months (IQR: 27.6 to 55.0) after the primary procedure. The mean pre-therapy SPEED II questionnaire score was 17.5 (IQR: 14 to 21), with a reduced mean post-therapy score of 10.2 (IQR: 6 to 14; 95% confidence interval [CI]: 8.8 to 11.5, P < .001). Patients with PRK tended to report more improvement. At the follow-up clinical evaluation, objective improvements were noted in tear break-up time (+1.9 sec; 95% CI: 1.3 to 2.5), reduction in grade of meibomian gland dysfunction (-0.69; 95% CI: -0.54 to -0.84), and corneal staining (-0.74; 95% CI: -0.57 to -0.91).

CONCLUSIONS

In this initial retrospective evaluation, a significant improvement in patient-reported dry eye symptoms was observed following thermal pulsation therapy. This treatment modality may have utility in the management of dry eye symptoms following laser vision correction, but further study is needed to define its role. [J Refract Surg. 2017;33(1):30-36.].

Analysis of the Pathogenic Factors and Management of Dry Eye in Ocular Surface Disorders

The tear film represents the interface between the eye and the environment. The alteration of the delicate balance that regulates the secretion and distribution of the tear film determines the dry eye (DE) syndrome. Despite having a multifactorial origin, the main risk factors are female gender and advanced age. Likewise, morphological changes in several glands and in the chemical composition of their secretions, such as proteins, mucins, lipidics, aqueous tears, and salinity, are highly relevant factors that maintain a steady ocular surface. Another key factor of recurrence and onset of the disease is the presence of local and/or systemic inflammation that involves the ocular surface. DE syndrome is one of the most commonly encountered diseases in clinical practice, and many other causes related to daily life and the increase in average life expectancy will contribute to its onset. This review will consider the disorders of the ocular surface that give rise to such a widespread pathology. At the end, the most recent therapeutic options for the management of DE will be briefly discussed according to the specific underlying pathology.

TFOS DEWS II iatrogenic report

Dry eye can be caused by a variety of iatrogenic interventions. The increasing number of patients looking for eye care or cosmetic procedures involving the eyes, together with a better understanding of the pathophysiological mechanisms of dry eye disease (DED), have led to the need for a specific report about iatrogenic dry eye within the TFOS DEWS II. Topical medications can cause DED due to their allergic, toxic and immuno-inflammatory effects on the ocular surface. Preservatives, such as benzalkonium chloride, may further aggravate DED. A variety of systemic drugs can also induce DED secondary to multiple mechanisms. Moreover, the use of contact lens induces or is associated with DED. However, one of the most emblematic situations is DED caused by surgical procedures such as corneal refractive surgery as in laser-assisted in situ keratomileusis (LASIK) and keratoplasty due to mechanisms intrinsic to the procedure (i.e. corneal nerve cutting) or even by the use of postoperative topical drugs. Cataract surgery, lid surgeries, botulinum toxin application and cosmetic procedures are also considered risk factors to iatrogenic DED, which can cause patient dissatisfaction, visual disturbance and poor surgical outcomes. This report also presents future directions to address iatrogenic DED, including the need for more in-depth epidemiological studies about the risk factors, development of less toxic medications and preservatives, as well as new techniques for less invasive eye surgeries. Novel research into detection of early dry eye prior to surgeries, efforts to establish appropriate therapeutics and a greater attempt to regulate and oversee medications, preservatives and procedures should be considered.

Effects of 3% trehalose as an adjuvant treatment after LASIK

PURPOSE

To evaluate the effect of 3% trehalose as an adjuvant in the standard treatment after laser-assisted in situ keratomileusis.

DESIGN

Interventional prospective comparative single-blind study.

SETTING

Department of Ophthalmology, Hospital Quirón Zaragoza, Spain.

METHODS

A total of 26 eyes (13 patients) were included, of which 12 eyes (group 1) received conventional treatment with lubricant drops of hyaluronic acid (0.15%) and 14 eyes (group 2) received, additionally, an ophthalmic solution of 3% trehalose. Pre- and postoperative quality-of-life tests and vital stains, tear breakup time, and osmolarity measurements were made.

RESULTS

We obtained statistically significant differences between the groups in the Symptom Assessment in Dry Eye test in all visits with respect to severity, and in the postoperative day 1 visit with respect to frequency, in all cases favoring the trehalose treatment. The values of osmolarity were not significantly different between groups. However, we did find significant differences in the Oxford scale in day 90 for the trehalose treatment (P<0.001), and in the National Eye Institute scale in day 30 (P=0.02).

CONCLUSION

The results of this exploratory study indicate that the adjuvant treatment with 3% trehalose could be superior with respect to the standard treatment, with improvements in the objective and subjective parameters of tear quality.

Recent advances in laser in situ keratomileusis-associated dry eye

Dry eye is the most common complication after laser in situ keratomileusis (LASIK). The major cause of LASIK-associated dry eye is corneal nerve damage. Early identification and treatment of post-operative dry eye are essential to prevent further ocular surface damage. This article reviews the recent studies of LASIK-associated dry eye, including clinical features, aetiology, risk factors, evaluations and treatment. The applications of novel technologies in LASIK-associated dry eye evaluation like anterior segment spectral-domain optical coherence tomography (SD-OCT) and corneal confocal microscopy are also introduced in this review.

Photorefractive keratectomy for patients with preoperative low Schirmer test value

Purpose

To compare dry eye signs and symptoms between patients with preoperative low and normal Schirmer test after Photorefractive keratectomy (PRK).

Methods

In this prospective, nonrandomized, comparative case series, 76 eyes of 76 patients were preoperatively categorized into two groups according to selected criteria for characterization of tear film status: the low Schirmer test value (STV) group and the normal STV group. For the tear function assessment, we performed a Schirmer test with and without anesthesia, tear break-up time (TBUT) test, and measurement dry eye symptoms using the Farsi translation of Ocular Surface Disease Index (OSDI) questionnaire pre- and 3 months post-operation.

Results

Postoperatively, the Schirmer and TBUT values were significantly lower in both groups than preoperatively (all p < 0.05). Deterioration in tear secretion was significantly greater in the low STV group (p = 0.012), but tear stability was more compromised in the normal STV group (p = 0.021). The changes in OSDI score were not significant between the two groups.

Conclusion

These results demonstrated that tear function deteriorates after PRK. Therefore, patients with low preoperative Schirmer test values should be thoroughly assessed for dry eye before proceeding with refractive surgery to eliminate postoperative complication.

Corneal sensitivity after small-incision lenticule extraction and laser in situ keratomileusis

PURPOSE

To longitudinally evaluate corneal sensitivity after small-incision lenticule extraction and compare the results with those in previous studies.

SETTING

London Vision Clinic, London, United Kingdom.

DESIGN

Retrospective case series.

METHODS

Consecutive myopic eyes treated with small-incision lenticule extraction using the Visumax femtosecond laser were studied. Corneal sensitivity was measured centrally and at 4 paracentral locations using a Cochet-Bonnet esthesiometer preoperatively and 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. Results were compared with averaged results from previous laser in situ keratomileusis (LASIK) and small-incision lenticule extraction studies.

RESULTS

The mean spherical equivalent was -6.85 diopters (D) ± 2.57 (SD). The mean age was 36 ± 11 years. After small-incision lenticule extraction, the preoperative mean central corneal sensitivity dropped from 54 mm preoperatively to 33 mm 1 day postoperatively, rising to 40 mm, 45 mm, 48 mm, 54 mm, and 55 mm over 12 months; it reached baseline at 6 months (P > .05). For 21 LASIK studies, the mean central corneal sensitivity dropped from 56 mm preoperatively to 6 mm at 1 day, rising to 14 mm, 23 mm, 34 mm, 45 mm, and 51 mm over 12 months. For 8 small-incision lenticule extraction studies, central corneal sensitivity dropped from 57 mm preoperatively to 39 mm at 1 week, then rose to 39 mm, 42 mm, 49 mm, 52 mm, and 54 mm over 12 months; it was higher than after LASIK at 1 week and 1, 3, and 6 months (P < .05).

CONCLUSION

Recovery of central corneal sensitivity to baseline was reached by 6 months after small-incision lenticule extraction and was higher than after LASIK for the first 6 months after surgery.

FINANCIAL DISCLOSURE

Dr. Reinstein is a consultant to Carl Zeiss Meditec AG, has a proprietary interest in the Artemis technology (Arcscan, Inc.), and is an author of patents related to very high-frequency digital ultrasound administered by the Center for Technology Licensing at Cornell University, Ithaca, New York, USA. No other author has a financial or proprietary interest in any material or method mentioned.

Early changes to dry eye and ocular surface after small-incision lenticule extraction for myopia

AIM

To investigate the early changes in dry eye symptoms, tear function and ocular surface following small-incision lenticule extraction (SMILE) for myopia.

METHODS

Ninety-seven consecutive patients (193 eyes) who underwent SMILE for myopia were observed in this longitudinal and retrospective study. Parameters evaluated included: subjective dry eye symptoms (dryness, foreign body sensation and photophobia), tear film breakup time (TBUT), Schirmer I test (S I T) without anesthesia, tear meniscus height (TMH) and corneal fluorescein staining. Each parameter was evaluated before, and subsequently at 1d, 1wk, 1 and 3mo after surgery.

RESULTS

Compared with preoperative data, dryness was noted to be significantly increased at 1wk and 1mo postoperatively (P<0.01). Symptoms of photophobia and foreign body sensation demonstrated significant differences at 1d and 1wk as compared with preoperative scores respectively (P<0.01). These values were decreased at 1 and 3mo post-surgery (P>0.05). Conversely the corneal staining scores were higher than the preoperative data at 1d, 1wk and 1mo (P<0.01), but were close to the preoperative level at 3mo postoperatively. There was a significant decrease in TMH at 1wk and 1mo (P<0.01), but the value was close to the preoperative level at 3mo postoperatively (P=0.16). The examination outcomes of S I T were significantly increased at 1d then reduced at 1wk after surgery (P<0.01). Each value subsequently returned to the baseline value at 1 and 3mo (P>0.05). TBUT was significantly decreased at all postoperative time points (P<0.01).

CONCLUSION

SMILE resulted in mild dry eye symptoms, tear film instability and ocular surface damages; however, these complications can recover in a short period of time.

Comprehensive Review of the Literature on Existing Punctal Plugs for the Management of Dry Eye Disease

Numerous designs of punctal and canalicular plugs are available on the market. This variety presents challenges to ophthalmologists when choosing punctal plugs for the management of various ocular conditions. The aim of this literature review is to provide a classification system for lacrimal occlusive devices based on their location and duration of action as well as to identify different characteristics of each one of them. We want to give a comprehensive overview on punctal and canalicular plugs including their manufacturing companies, indications, and complications that have been reported in various articles. PubMed and Google Scholar were used to identify articles written in English as well as few articles written in Japanese, Chinese, Slovak, and Spanish that had abstracts in English. Nine different companies that manufacture punctal and canalicular plugs were identified and their plugs were included in this review. Punctal and canalicular plugs are used in the management of various ocular conditions including dry eye disease and punctal stenosis as well as in ocular drug delivery. Although they are a relatively safe option, associated complications have been reported in the literature such as infection, allergic reaction, extrusion, and migration.