Retinal Pigment Epithelium Transplantation: Past, Present, and Future

Retinal pigment epithelium (RPE) is a monolayer of cells situated between photoreceptors and the underlying choroid. It is essential for normal retinal function. Damaged RPE is associated with diseases such as age-related macular degeneration, Stargardt’s macular dystrophy, and retinitis pigmentosa. RPE cells can easily be visualized in vivo, sustainable in vitro, and differentiated from stem cells with a relatively straightforward protocol. Due to these properties and the clinical significance of this epithelium in various retinal diseases, RPE transplantation as a treatment modality has gained considerable interest in the last decade. This paper presents the main techniques for RPE transplantation and discusses recent clinically relevant publications

Role of stem cells in regenerative treatment of dry eye disease caused by lacrimal gland dysfunction

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Seasonal variations in presenting symptoms and signs of dry eye disease in Norway

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Late onset post-LASIK keratectasia with reversal and stabilization after use of latanoprost and corneal collagen cross-linking

We report a case of late onset keratectasia after laser in situ keratomileusis (LASIK) and its quick reversal and stabilization after use of latanoprost and riboflavin/ultraviolet-A corneal collagen cross-linking (CXL). A 39-year-old man with normal intraocular pressure developed a rapid deterioration of vision in his left eye 6 years after LASIK-retreatment for high myopic astigmatism. Keratectasia was diagnosed by corneal topography and ultrasound pachymetry. After two months of treatment with latanoprost and a minor intraocular pressure reduction, uncorrected distance visual acuity improved from 20/100 to 20/20 and corneal topography showed reversal of keratectasia. CXL was performed after the reversal to achieve long-term stabilization. At 1, 3, 6, 13 and 39 months followup exams after the CXL, stable vision, refraction, and topography were registered. This case shows that keratectasia may rapidly occur several years after LASIK and that a quick reversal and stabilization may be achieved by use of latanoprost followed by CXL

The work-related burden of dry eye

Purpose: To investigate the relationship between dry eye disease (DED) and work functioning, unemployment, absenteeism, and worry about job loss. Methods: DED and unemployment, absenteeism, and ‘worry about job loss’ were assessed in 71,067 subjects (18–65 years, 60% female) from the Dutch population-based Lifelines cohort using the Women's Health study questionnaire and single-item questions, respectively. Work functioning was assessed in 32,475 participants using the Work role functioning questionnaire 2.0. The relationships between DED and work measures were assessed with logistic regression models, corrected for age, sex, BMI, income, educational level, smoking, and 48 comorbidities. Results: 8.3% of participants had DED and had more impaired work functioning compared to those without DED (49.2% vs 41.1%, OR 1.21, 95% CI 1.10–1.32, corrected for demographics, smoking and 48 comorbidities). DED carried a similar risk of impaired work functioning as rheumatoid arthritis. For participants with highly symptomatic dry eye impaired work functioning was even higher (59.1%) and similar to that of depression. The impaired work functioning seen with increasing symptoms were greater in undiagnosed subjects versus diagnosed subjects (P = 0.03). After correction for comorbidities, DED remained tied to absenteeism and increased worry about job loss, but not unemployment. Conclusion: DED was linked to impaired work functioning and absence, but not unemployment. DEDs impact on work functioning is comparable to that of other severe chronic disorders, and undiagnosed subjects may be more affected. This highlights the importance of recognizing DED as a severe disorder and of screening for dry eye in the workplace to aid with diagnosis and treatment.</p

The relationship between dry eye and sleep quality

Purpose: Sleep is an important determinant of health and quality of life. This study aimed to clarify the association between dry eye and sleep quality using a large population-based cohort. Methods: 71,761 participants (19-94 yrs, 59.4% female) from the Lifelines cohort in the Netherlands were assessed for dry eye using the Women's Health Study Dry Eye Questionnaire. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Logistic regression was used to examine the relationship between poor sleep quality (PSQI score > 5) and dry eye, while correcting for age, sex, BMI, education, income, and 51 possible confounding comorbidities, including autoimmune diseases and psychiatric disorders. Results: Overall, 8.9% of participants had dry eye. Of these, 36.4% had poor sleep quality compared to 24.8% of controls (OR 1.52 (95%CI 1.44-1.60), P < 0.0001, corrected for age and sex). After correcting for all comorbidities, dry eye was still associated with poor sleep (OR 1.20 (95%CI 1.11-1.28), P < 0.0001). This relationship was seen across all ages and sexes. Patients with dry eye scored worse on all subcomponents of the PSQI. Almost one-in-two (44.9%) persons with dry eye symptoms "often" or "constantly" had poor sleep quality. This proportion was similar to participants with sleep apnea and osteoarthritis. Additionally, increasing symptom frequency was tied to increased prevalence of poor sleep quality. Conclusions: All components of sleep quality were significantly reduced in participants with dry eye, even after correcting for comorbidities. These results indicate the substantial impact of dry eye on patients' lives, especially for those with frequent symptoms

A comparison between hyaluronic acid and other single ingredient eye drops for dry eye, a review

Dry eye disease (DED) is a highly prevalent and debilitating condition. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has a long history as a safe and effective DED treatment. HA is frequently used as a comparator when assessing other topical DED treatments. This study aims to summarise and critically evaluate the literature describing all isolated active ingredients that have been directly compared with HA in the treatment of DED. A literature search was conducted in Embase using Ovid on the 24th of August 2021 and in PubMed including MEDLINE on the 20th of September 2021. Twenty-three studies met the inclusion criteria, 21 of which were randomised controlled trials. Seventeen different ingredients representing six treatment categories were compared with HA treatment. Most measures showed no significant difference between treatments, suggesting either equivalency of treatments or that studies were underpowered. Only two ingredients were represented in more than two studies; carboxymethyl cellulose treatment appears equivalent to HA treatment, while Diquafosol treatment appears superior to HA treatment. Drop-frequency varied from one to eight drops daily. No single study explained the choice of drop frequency. Nine studies used a HA concentration of 0.1% which may be below therapeutic levels. Nine studies reported using preserved formulations, six of them with differences in preservatives between the compared groups. Thirteen studies were financially linked to industry. No major complications were reported. Studies were not designed to find differences in treatment effects for different types or severities of DED. HA is a good comparator treatment when assessing other DED treatments, although consensus after decades of use is still lacking for best choice of concentration, molecular weight and drop tonicity. Well-designed studies are needed to determine an evidence-based standard for HA treatment to be used as comparator.publishedVersio

Safety and efficacy of epithelium-on corneal collagen cross-linking using a multifactorial approach to achieve proper stromal riboflavin saturation

Purpose: To evaluate the efficacy and safety of epithelium-on corneal collagen cross-linking (CXL) using a multifactorial approach to achieve proper stromal riboflavin saturation. Methods: This non-randomized retrospective study comprised 61 eyes with progressive keratoconus treated with epithelium-on CXL. Chemical epithelial penetration enhancement (benzalkonium chloride-containing local medication and hypotonic riboflavin solution), mechanical disruption of the superficial epithelium, and prolongation of the riboflavin-induction time until verification of stromal saturation were used before the UVA irradiation. Uncorrected and corrected distance visual acuity (UDVA, CDVA), refraction, corneal topography, and aberrometry were evaluated at baseline and at 1, 3, 6, and 12 months postoperative. Results: At 12-month, UDVA and CDVA improved significantly. None of the eyes lost lines of CDVA, while 27.4% of the eyes gained 2 or more lines. Mean spherical equivalent decreased by 0.74 D, and mean cylindrical reduction was 1.15 D. Irregularity index and asymmetry from Scheimpflug-based topography and Max-K at the location of cone from Placido-based topography showed a significant decrease. Higher-order-aberration data demonstrated a slight reduction in odd-order aberrations S 3, 5,7 ( = 0.04). Postoperative pain without other complications was recorded. Conclusion: Epithelium-on CXL with our novel protocol appeared to be safe and effective in the treatment of progressive keratoconus.publishedVersio

Predicting an unstable tear film through artificial intelligence

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The physical and mental burden of dry eye disease:A large population-based study investigating the relationship with health-related quality of life and its determinants

Purpose: This large cross-sectional population-based study investigated the relationship between dry eye disease (DED) and health-related quality of life (HR-QoL). Methods: Dry eye and HR-QoL were assessed in 78,165 participants (19-94 yrs, 59.2% female) from the Dutch population-based Lifelines cohort, using the WHS and the SF36 questionnaire, respectively. Logistic regression was used to assess the relationship between DED and below median Physical Component Summary (PCS) and Mental Component Summary (MCS) score, corrected for age, sex, education, BMI, and 52 comorbidities. Results: Overall, 8.9% of participants had DED. Participants with DED had an increased risk of low PCS (OR 1.54 (95% CI 1.46-1.62)) and MCS scores (OR 1.39 (95% CI 1.32-1.46)), corrected for age and sex. This risk remained significant after correction for comorbidities (P < 0.0005). Increasing DED symptom frequency was associated with decreasing HR-QoL (P < 0.0005). Undiagnosed DED subjects had a significantly increased risk of low mental HR-QoL with increasing dry eye symptoms compared to diagnosed subjects (P < 0.0005). Compared to allergic conjunctivitis, glaucoma, macular degeneration and retinal detachment, DED showed the highest risk of low HR-QoL. Compared to other common systemic and chronic disorders, such as depression, rheumatoid arthritis, and COPD, DED was distinctive by having a substantial reduction in both PCS and MCS. Conclusion: DED is associated with substantial reductions in both physical and mental HR-QoL, also after correction for associated comorbidities. Not having a diagnosis is associated with worse mental HR-QoL in subjects with severe DED. Our results underline the importance of recognizing dry eye as a serious disorder