The cornea, with its delicate structure, is vulnerable to damage from physical, chemical, and genetic factors. Corneal transplantation, including penetrating and lamellar keratoplasties, can restore the functions of the cornea in cases of severe damage. However, the process of corneal transplantation presents considerable obstacles, including a shortage of available donors, the risk of severe graft rejection, and potentially life-threatening complications. Over the past few decades, mesenchymal stem cell (MSC) therapy has become a novel alternative approach to corneal regeneration. Numerous studies have demonstrated the potential of MSCs to differentiate into different corneal cell types, such as keratocytes, epithelial cells, and endothelial cells. MSCs are considered a suitable candidate for corneal regeneration because of their promising therapeutic perspective and beneficial properties. MSCs compromise unique immunomodulation, anti-angiogenesis, and anti-inflammatory properties and secrete various growth factors, thus promoting corneal reconstruction. These effects in corneal engineering are mediated by MSCs differentiating into different lineages and paracrine action via exosomes. Early studies have proven the roles of MSC-derived exosomes in corneal regeneration by reducing inflammation, inhibiting neovascularization, and angiogenesis, and by promoting cell proliferation. This review highlights the contribution of MSCs and MSC-derived exosomes, their current usage status to overcome corneal disease, and their potential to restore different corneal layers as novel therapeutic agents. It also discusses feasible future possibilities, applications, challenges, and opportunities for future research in this field.

Purpose: To compare clinical outcomes of a new monofocal intraocular lens (IOL) with enhanced intermediate function and an extended depth-of-focus (EDoF) IOL. Setting: Asan Medical Center, Seoul, Korea. Design: Nonrandomized prospective comparative case series. Methods: Patients presenting for cataract surgery and meeting all inclusion and exclusion criteria were implanted with a new monofocal IOL with enhanced intermediate function (Tecnis Eyhance ICB00) or an EDoF IOL (Tecnis Symfony ZXR00) bilaterally. Uncorrected (UDVA), uncorrected intermediate (UIVA), uncorrected near (UNVA), and corrected distance visual acuity (CDVA), defocus curves, and contrast sensitivity were compared after 3 months. Patients were administered questionnaires regarding visual symptoms, spectacle independence, overall satisfaction, and lens recommendations. Results: 24 patients (48 eyes) were enrolled in the Eyhance group and 20 patients (40 eyes) in the Symfony group. Monocular and binocular UDVA, UIVA, and CDVA were similar in the 2 groups. Monocular UNVA and spectacle independence for near distance were better in the Symfony group, whereas binocular UNVA did not differ significantly in the 2 groups. Contrast sensitivity, glare and halo, satisfaction, and recommendation rates were similar in the 2 groups. Although some dissatisfaction and severe glare and halo were reported in the Symfony group, none of these was reported in the Eyhance group. Conclusions: Bilateral implantation of the Eyhance ICB00 IOL provided comparable clinical performances as bilateral implantation of the Symfony ZXR00 IOL. Binocular UNVA was similar, although spectacle independence was higher in the Symfony group, but this was at the expense of more glare and halos.

Dry eye disease (DED) is an emerging health issue affecting millions of individuals annually. Ocular surface disorders, such as DED, are characterized by inflammation triggered by various factors. This condition can lead to tear deficiencies, resulting in the desiccation of the ocular surface, corneal ulceration/perforation, increased susceptibility to infections, and a higher risk of severe visual impairment and blindness. Currently, the clinical management of DED primarily relies on supportive and palliative measures, including the frequent and lifelong use of different lubricating agents. While some advancements like punctal plugs, non-steroidal anti-inflammatory drugs, and salivary gland autografts have been attempted, they have shown limited effectiveness. Recently, there have been promising developments in the treatment of DED, including biomaterials such as nano-systems, hydrogels, and contact lenses for drug delivery, cell-based therapies, biological approaches, and tissue-based regenerative therapy. This article specifically explores the different strategies reported so far for treating DED. The aim is to discuss their potential as long-term cures for DED while also considering the factors that limit their feasibility and effectiveness. These advancements offer hope for more effective and sustainable treatment options in the future.

Because of the limited differentiation capacity of human corneal endothelial cells (CECs), stem cells have emerged as a potential remedy for corneal endothelial dysfunction (CED). This study aimed to demonstrate the differentiation of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) into CECs and to investigate the efficacy of MSC-induced CEC injection into the anterior chamber in a rabbit model of CED. Human UC-MSCs were differentiated into CECs using medium containing glycogen synthase kinase 3β inhibitor and two types of Rho-associated protein kinase inhibitors. In the MSC-induced CECs, CEC-specific proteins were identified through immunohistochemistry and changes in CEC-specific gene expressions over time were confirmed through quantitative RT-PCR. When MSC-induced CECs were injected into a rabbit model of CED, corneal opacity and neovascularization were improved compared with the non-transplanted control or MSC injection group. We also confirmed that MSC-induced CECs were well engrafted as evidenced by human mitochondrial DNA in the central cornea of an animal model. Therefore, we demonstrated the differentiation of UC-MSCs into CECs in vitro and demonstrated the clinical efficacy of MSC-induced CEC injection, providing in vivo evidence that MSC-induced CECs have potential as a treatment option for CED.

Objectives: This study compared the visual outcomes and optical quality of two monofocal, aspheric intraocular lenses (IOLs; CT LUCIA 621P, Carl Zeiss Meditec; Eyhance ICB00, Johnson & Johnson Vision) by evaluating visual acuity, contrast sensitivity, and higher-order aberrations 1 month post-cataract surgery. Methods: In this retrospective, comparative study, 120 eyes (72 patients) that underwent cataract surgery with either CT LUCIA 621P (Lucia group) or Eyhance ICB00 (Eyhance group) implantation (60 eyes/group) were retrospectively investigated. Visual acuity at various distances and defocus curves were measured 1 month postoperatively. Optical quality was assessed by comparing contrast sensitivity and internal coma, spherical, and total aberrations by using iTrace (Tracey Technology), a ray-tracing-type aberrometer. Results: The visual acuity and defocus curves were similar between the two IOLs 1 month postoperatively. The Lucia group showed better contrast sensitivity at higher spatial frequencies: 12 cpd (p < 0.001, 1.32 LogCS vs. 1.02 LogCS) and 18 cpd (p = 0.009, 0.74 LogCS vs. 0.47 LogCS) unilaterally and 18 cpd (p = 0.044, 0.94 LogCS vs. 0.60 LogCS) bilaterally. Postoperative internal spherical aberration was significantly lower in the Lucia group (p < 0.001, −0.04 µm vs. −0.003 µm). Internal coma and total aberrations were similar. Conclusions: The visual acuity and defocus curves of the Lucia and Eyhance groups were comparable 1 month post-cataract surgery. The Lucia group’s superior contrast sensitivity and lower postoperative internal spherical aberration were due to differences in IOL designs, particularly the power variation patterns.

Objectives: To compare the long-term efficacy and safety of intense pulsed light (IPL) treatments using a 590-nm and an acne filter. Methods: In this prospective, randomized, paired-eye trial study, 30 patients with moderate and severe meibomian gland dysfunction (MGD) were followed up for at least one month after their last treatment. Group A received IPL treatment with an acne filter, a type of notch filter that blocks wavelengths between 600 and 800 nm, allowing IPL to emit wavelengths between 400–600 nm and 800–1200 nm. Group B received treatment with a 590 nm filter, a type of cut-off filter that blocks wavelengths below 590 nm. Clinical parameters, including tear osmolarity, matrix metalloproteinase (MMP)-9 expression, tear break-up time, ocular surface staining scores, Schirmer’s test I, lid margin telangiectasia scores, MG expressibility/secretion scores, and Ocular Surface Disease Index scores, were measured at baseline, 1, 6, and 12 months after their last treatment. Results: In the linear mixed model, significant time effects on all clinical parameters, except for MMP-9 grades and Schirmer’s test I results, were observed within each group. However, interactions between time points (baseline, 6 months, 12 months) and groups (Group A, B) were not significant. The generalized estimating equation model showed no significant interaction between time points and groups for MMP-9 positivity; however, a significant time effect on MMP-9 positivity was observed in Group A, with a decrease at 12 months after their last treatment when compared to baseline and 6 months. Conclusions: The IPL treatment modality for moderate to severe MGD demonstrated a significant therapeutic effect for one year under strictly controlled self-administration of other treatments. IPL treatment using acne filter is a promising treatment option for reducing MMP-9 positivity in MGD patients.