[Novel current and future therapy options for treatment of dry eye disease]

Overview of CFTR activators and their recent studies for dry eye disease: a review

The cystic fibrosis transmembrane conductance regulator (CFTR) gets activated via the cAMP signaling pathway and is present in various secretory epithelial cells, including conjunctival and corneal epithelial cells. Activation of CFTR leads to fluid secretion in both mouse and human ocular surfaces. Dry eye disease is a significant health problem for which limited therapeutic options are available. In this review, on the one hand, small molecule CFTR activators with different chemical structures are summarized, and on the other hand, the pharmacological activity test and structural optimization of small molecule CFTR activators in the treatment of dry eye are outlined. The purpose of this review is to highlight the important role of CFTR activators in the treatment of dry eye disease and their potential as a new strategy for the treatment of dry eye disease.

Effects of Serial Sessions of Activa Mask for the Treatment of Meibomian Gland Dysfunction

INTRODUCTION

To analyze outcomes on objective ocular surface parameters and subjective symptoms of serial weekly sessions using the Activa mask in patients with meibomian gland dysfunction (MGD).

METHODS

This is a prospective study including patients with symptomatic MGD who were treated with four weekly sessions using the Activa mask (SBM Sistemi, Turin, Italy). Noninvasive ocular surface examination was carried out before (T0) and 2 weeks after the last mask session (T1) using Idra (SBM Sistemi, Turin, Italy) for the measurement of: (1) noninvasive break-up time (NIBUT); (2) lipid layer thickness (LLT); (3) tear meniscus height (TMH); (4) meibomian gland loss (MGL) of upper and lower eyelids. The I-Pen tear osmolarity system (I-Med Pharma Inc, Dollard-des Ormeaux, Quebec, Canada) was used to measure tear osmolarity values. Ocular discomfort symptoms were ascertained by means of the ocular surface disease index (OSDI) questionnaire.

RESULTS

All 25 patients (11 males, 14 females; mean age 57.1 ± 11.9 years) regularly completed the cycle of four mask sessions. No patients used prohibited medications, and no device-related adverse events were noted. At T1, mean values of NIBUT and LLT increased significantly compared to T0 (respectively from 6.0 ± 1.4 to 6.6 ± 1.2 s, P = 0.043, and from 53.2 ± 17.4 to 65.3 ± 16.3 nm, P < 0.001), while mean values of MGL and tear osmolarity decreased significantly (respectively from 17.1 ± 9.3 to 15.1 ± 8.0%, P = 0.014, and from 307.3 ± 12.2 to 301.5 ± 6.8 mOsm/l, P = 0.005). In parallel, OSDI score reduced significantly from 62.4 ± 11.7 at T0 to 34.5 ± 11.2 at T1 (P < 0.001).

CONCLUSION

Weekly serial sessions using the Activa mask significantly improved objective parameters of the ocular surface as well as subjective ocular discomfort symptoms in patients with recalcitrant MGD. As a further benefit from the treatment, patients were able to avoid the use of concomitant medications, apart from tear substitutes, throughout the study.

Bacteria and Dry Eye: A Narrative Review

(1) Background: Dry eye is a multifactorial disease of the ocular surface, the incidence of which has been increasing sharply. The pathogenesis of dry eye, especially in terms of the bacterial flora, has drawn great attention. Additionally, the potential treatment methods need to be explored. (2) Methods: We reviewed more than 100 studies and summarized them briefly in a review. (3) Results: We summarized the bacterial communities found on the ocular surface in the general population and patients with dry eye and found a relationship between dry eye and antibiotic therapy. We identified the possible mechanisms of bacteria in the development of dry eye by discussing factors such as the destruction of the antibacterial barrier, infectious diseases, microbiome homeostasis, inflammatory factors on the ocular surface and vitamin deficiency. (4) Conclusion: We systematically reviewed the recent studies to summarize the bacterial differences between patients with dry eye and the general population and brought up several possible mechanisms and possible treatment targets.

[Preoperative management of subconjunctival/sub-Tenon's glaucoma surgery with special consideration of the gel implant (XEN®)]

BACKGROUND

When using subconjunctival/sub-Tenon's ab interno glaucoma surgical procedures, patient selection and preoperative management are essential to reduce postoperative scarring of the bleb.

OBJECTIVE

The aim of this study was to compile a list of risk factors that may have an unfavorable effect on the scarring process.

METHOD

A literature search was carried out in PubMed with respect to the scarring process of the gel implant XEN®.

RESULTS

Ophthalmological risk factors for conjunctivoscleral/Tenon's wound healing process include dry eye, allergies, use of eye drops containing preservatives and previous eye surgery.

CONCLUSION

The preoperative administration of artificial tear substitutes, corticosteroids and the fundamental change to preservative-free eye drops can support the normalization of a chronic inflammatory altered conjunctiva and thus positively influence the wound healing process after surgery.

Application of botulinum toxin in Horner's muscle for the treatment of dry eye

OBJECTIVE/METHODS

The aim of this study is to describe the use of botulinum toxin to increase tear retention in patients with dry eye, using the description of 2 cases.

RESULTS

Patients with moderate to severe dry eye that were given an injection of type A botulinum toxin in the Horner's muscle. The results at one month and 3 months are reported. An assessment was made of the subjective perception of the patient as regards any improvement, as well as taking into account, the Ocular Surface Disease Index, superficial punctate keratitis, and the time of the tear rupture and tear meniscus. A significant improvement was observed in the subjective perception of the patient, the Ocular Surface Disease Index, superficial punctate keratitis, and the time of the tear rupture and tear meniscus at one month after treatment, and the good results still being maintained at the third month. There were no adverse events.

DISCUSSION

The use of type A botulinum toxin can be considered as an alternative to increase tear retention in moderate to severe dry eye, with a good response during the first month, with an acceptable response still being maintained at the third month. Given the temporary effect of the drug, further treatments would be required.