Night-time blood pressure dipping, but not 24-h blood pressure level, is linked to increased 24-h ocular volume slope

ABSTRACT Purpose: This study investigated the relationship between blood pressure and intraocular pressure in treatmentnaive, non-glaucoma patients with different blood pressure statuses, focusing on the 24-h ocular volume and nocturnal blood pressure decline. Methods: Treatment-naive, non-glaucoma patients undergoing hypertension evaluation were enrolled as study participants. Simultaneous 24-h ambulatory blood pressure measurement and 24-h ocular volume recording with a contact lens sensor. We also compared ocular volume curve parameters between normotensive and hypertensive patients, as well as between those with and without nocturnal blood pressure decline. Results: A total of 21 patients, including 7 normotensive and 14 treatment-naive hypertensive individuals, were included in the study. of them, 11 were dippers and 10 were non-dippers. No significant difference in the 24-h ocular volume slope was observed between the hypertensive and normotensive patients (p=0.284). However, dippers had a significantly higher 24-h ocular volume slope (p=0.004) and nocturnal contact lens sensor output (p=0.041) than non-dippers. Conclusion: Nocturnal blood pressure decline, rather than the blood pressure level, is associated with the increased 24-h ocular volume slope and nocturnal ocular volume. Further studies are required to determine whether the acceleration of glaucoma progression in dippers is primarily due to low blood pressure, high intraocular pressure, or a combination of both.

A Case of Bacterial Keratitis in a Patient Using Orthokeratology and Soft Contact Lenses.

A 63-year-old male with high myopia developed sudden visual loss, eyelid swelling, eye pain, discharge, and tearing in his left eye while wearing soft contact lenses (CLs) during the day and orthokeratology lenses at night. At the initial visit, his corrected visual acuity in the left eye was 20/1000, with a ring-shaped ulcer in the central cornea, corneal infiltration across the entire cornea, and conjunctival hyperemia. Pseudomonas aeruginosa was detected from corneal scrapings, and after antibiotic treatment, the ulcer healed with corneal opacity remaining. On the 60th day, corrected visual acuity of 20/20 was achieved with rigid gas-permeable CLs. To prevent CL-related ocular complications, eye care professionals must carefully evaluate the suitability of all CLs, including orthokeratology.

The relationship between contact lens ultraviolet light transmittance and myopia progression: a large-scale retrospective cohort study.

Background: The prevalence of myopia is increasing dramatically around the world, and many studies have suggested the possibility that ultraviolet (UV) light is effective to prevent the onset and progression of myopia. However, UV is a risk factor for diseases that cause refractive errors such as cataract and pterygium. In this study, we evaluated the relationship between UV exposure and myopia progression. Methods: The dataset consisted of a total of 337 396 eyes of patients in the 12-to-29-year age range, who were prescribed soft contact lenses (SCL) for refractive error at Okada Eye Clinic in Japan between 2002 and 2011. They were tracked over a five-year period and did not change the type of SCL. In this retrospective cohort study based on medical records, we divided patients into two groups, one prescribed SCL with UV protection (UV-SCL), and another prescribed SCL without UV protection (UV + SCL). Results: Change in refractive power over five years was measured and results compared. It was -0.413 diopter (D) in the UV-SCL group and -0.462 D in the UV + SCL group. Thus, the progression of myopia was slower in the UV-SCL group. The results were also analyzed separately by gender and degree of myopia at the time of initial prescription, which all showed significant differences (P < 0.001). Conclusion: Results suggest that UV exposure may advance myopia. Further research is needed to investigate the underlying mechanisms that could explain this.

Influence of Contact Lens Parameters on Cornea: Biomechanical Analysis.

This study presents a finite element analysis to model ocular biomechanics and the interactions between the human eye and contact lenses in the closed-eye condition. The closed-eye state, where the eyelids are fully shut, presents challenges for experimental measurements due to the invasive nature of accessing and analysing the contact lens and corneal interface, making simulation tools valuable for accurate characterisation. The primary objective of this study was to examine how CLs fold and twist and their impact on the cornea when the eye is closed. The secondary aim of this study was to assess how crucial contact lens parameters (Young's modulus, base curve, and diameter) influence corneal stress distribution and the overall fit of the lens on the eye. The findings show that increasing Young's modulus significantly reduces corneal stress and promotes uniform stress distribution, making it the most influential factor for wearer comfort and safety. While base curve and diameter variations primarily affect contact area, their impact on stress distribution is minimal. This research provides insights for improving contact lens design and enhancing safety for contact lens wearers.

The contact lens-tear film interface: Investigating the tear envelope.

PURPOSE: To explore the complex interface between the tear film, a unique mucosal fluid which is fundamental to ocular homeostasis and optimal vision, and an in-situ contact lens. This study exploits the use of a unique tear envelope (TE) extraction technique, which harvests the material-influenced layer of tear film that is in intimate contact with the lens during wear, to specifically investigate the influence of contact lens wear on tear film protein dynamics. METHODS: TEs were collected from freshly removed worn lens using a novel microcentrifuge 'piggyback' technique. Two distinct ex vivo studies were performed to investigate the key influencing factors involved. Non lens-wearing tear samples were also collected from all wearers. A compositional protein profile for each TE and tear film (TF) sample was obtained using an Agilent 2100 Bioanalyzer lab-on-a-chip microfluidic assay which detected proteins in a 14-230 kDa range. RESULTS: The data demonstrated that the TE protein compositional profile was quite distinct from either that of tear components deposited on the lens or those held in the tear menisci. For example, for one of the participant subgroups the tear protein average values in tears (n = 39) were determined at 35.2 ± 2.5 % lysozyme, 17.2 ± 0.6 % lipocalin, 7.3 ± 1.6 % IgA, 20.3 ± 1.3 % lactoferrin and 0.4 ± 0.4 % albumin as a function of total protein detected. In contrast, the average TE values were measured at 49.2 ± 3.7 %, 21.3 ± 3.9 %, 7.8 ± 1.6 % and 10.2 ± 1.7 % and 1.3 ± 2.8 % respectively with omafilcon A wear. In addition, 63 % of all TE samples (n = 180) (wearing lotrafilcon B and omafilcon A lenses) were albumin positive compared with only 19 % of all pre-lens insertion tear film samples (n = 237). CONCLUSIONS: The TE approach not only allows material differentiation, but it can determine changes in the ocular host response that may otherwise be missed by sole non lens-wearing tear film sample analysis.

Hydrogel-Embedded Polydimethylsiloxane Contact Lens for Ocular Drug Delivery.

Topical administration is the commonly preferred method of administering ophthalmic formulations, with the majority of available medications in the form of eye drops or ointments. However, the topical application of ophthalmological medications has less bioavailability and a short residence time because of the physiological and anatomical constraints of the eye, making efficient ophthalmic drug delivery a challenging task. Microfluidic contact lenses have the advantage of delivering drugs into the eye in a controlled and on-demand manner. Here, we showcase the use of hydrogel-embedded microcavities on PDMS-based contact lenses for ocular drug delivery applications. The fabrication technique adopted here is the spontaneous formation of the spherical cavity by hydrogel monomer droplet, followed by the simultaneous thermal curing of hydrogel and PDMS, creating a spherical cavity as small as 150 µm. The spherical cavity is embedded with pH-responsive hydrogel for on-demand drug delivery. The drug loaded in the hydrogel matrix is released into the ocular environment by diffusion. The spherical cavity with a narrow opening restricts the diffusion to a minimum under normal ocular pH conditions(pH > 6). When the ocular pH reduces (pH < 6), the pH-responsive hydrogel inside the spherical cavity deswell and accelerates the drug release.

Differential impact of combined therapy and monotherapy with 0.05% atropine eyedrops and dual focus contact lenses on choroid.

PURPOSE: To investigate changes in the choroid and axial length (AL) during one month of combined therapy and monotherapy with 0.05% atropine and dual-focus soft contact lens (DFCL), and the impact after discontinuation. METHODS: Myopic adults randomly received three interventions: 0.05 % atropine, DFCL, and 0.05 % atropine combined with DFCL. Choroidal thickness (ChT), choroidal vascularity index (CVI) and AL were measured at baseline, 3, 7, 14, and 30 days after intervention, and 1, 2, 7, 14, and 30 days after discontinuation. RESULTS: The ChT thickened and AL decreased after one month of combination therapy (24.19 ± 4.13 µm, P = 0.001; -40.35 ± 9.55 µm, P = 0.024) or 0.05 % atropine (20.52 ± 4.35 µm, P = 0.008; -8.07 ± 7.22 µm, P = 0.002) but not DFCL (8.95 ± 4.25 µm, P > 0.999; -14.89 ± 7.28 µm, P > 0.999). The increase in ChT and decrease in AL persisted for 2 days after 0.05 % atropine was discontinued, persisted for 7 days and 14 days after combination therapy was discontinued. There was no significant change in the CVI after one month use or withdrawal of any intervention (P > 0.999). After one month of combination therapy, significant correlations were observed between the baseline CVI and changes in ChT (r = 0.485, P = 0.035) or AL (r = -0.589, P = 0.008). CONCLUSION: Monotherapy involving 0.05% atropine or the combination of 0.05% atropine with DFCL significantly affected ChT thickening and AL shortening. These changes were maintained for a longer duration post combination intervention. The baseline CVI was associated with changes in ChT and AL during combination treatment.

Management of traumatic macrostriae in an undisplaced LASIK Flap.

Purpose: To present a case of traumatic late macrostriae of Laser in situ keratomileusis (LASIK) flap managed by flap lifting, stretching, and polishing. Material and method: A patient presented with a history of defective vision in his right eye following trauma with a rubber ball 10 days ago. He had undergone an uneventful LASIK surgery 4 years ago. Ocular examination showed visual acuity of 20/200, multiple parallel radiating folds in an undisplaced LASIK flap in the inferonasal quadrant, and sphincter tear. This case required an urgent surgical intervention. Epithelial debridement, flap lifting, gentle stretching, and irrigation were performed to smooth out the striae. A bandage contact lens was applied to ensure proper wound apposition. Results: The postoperative period was without complications, and the patient achieved a final visual acuity of 20/20. Discussions: The insufficient wound healing of the LASIK flap results in a cornea with compromised biomechanical strength. They remain susceptible to trauma for a long duration after surgery. Traumatic injury to these eyes can lead to late macrostriae formation, which results in visual deterioration. Cases of macrostriae presenting late require surgical debridement of epithelium, which keeps these folds fixed. It should be followed by flap irrigation and stretching to smooth these striae. Conclusions: Since LASIK wound healing is always incomplete, it is crucial to inform patients about the potential risk of trauma. Any traumatic flap injury requires thorough examination and proper management of these cases results in excellent visual gain.

An unusual cause of hemolacria: retained contact lens in upper fornix.

A 64-year-old male was referred for complaints of blood in tears and bloody discharge of unknown cause in the left eye. The patient was a chronic bandage contact lens (BCL) user. He had no history of recent trauma. A blood-stained BCL was present on the cornea in the left eye, which was removed. The ocular surface was dry with vascularization of the cornea. Double eversion of the upper eyelid with a Desmarre's retractor revealed a pyogenic granuloma with large papillae on the forniceal conjunctiva and a folded BCL hidden in the fornix. The folded BCL was carefully removed from the "upper fornix trap" and topical steroid eyedrops were prescribed.

Corneal endothelial density and morphology in long-term soft contact lens users in Japan: a retrospective cross-sectional study of 17,732 eyes.

PURPOSE: There is a lack of long-term and large-scale studies on the adverse effects of soft contact lenses (SCLs) on the corneal endothelia of Asian populations. Here, we aimed to examine the effects of long-term SCL use on corneal endothelial density and morphology. MATERIALS AND METHODS: This retrospective study involved consecutive patients at the Miyata Eye Hospital (Miyazaki, Japan), who had used SCLs for more than 1 year. Patients with ophthalmological disorders without refractive errors were excluded. The period of SCL use, SCL type, corneal endothelial cell density (ECD), appearance rate of hexagonal cells (HEX), and coefficient of variation of cells (CV) were analyzed. RESULTS: In total, 17,732 eyes of 8866 patients were included in the analysis (age, 26.0 ± 8.8 years). The mean period of SCL use was 6.3 ± 5.4 years. Multivariate regression analysis revealed that ECD and HEX were significantly negatively correlated with the period of SCL use, age, and sex (p < 0.001 for all). The CV was significantly positively correlated with the period of use (p < 0.001), sex (p = 0.002), and age (p < 0.001). CONCLUSIONS: Corneal ECD, HEX, and CV were significantly associated with the period of SCL use in long-term users. It is essential to regularly check the corneal endothelium in patients with a history of long-term SCL use.

Compliance with rigid gas-permeable contact lens use in children younger than 6 years in China: a 6-year retrospective study.

PURPOSE: To explore the abandonment rate and factors influencing the use of rigid gas-permeable contact lenses (RGPCL) among children aged < 6 years. METHODS: This retrospective case series study included 70 children aged < 6 years who were fitted with RGPCL for visual rehabilitation between January 2016 and December 2021. We collected data on indications, discontinuation rates, and reasons for discontinuation from medical records and via telephone calls and investigated the factors influencing contact lens abandonment. RESULTS: The median age of the 70 participants was 5.0 (interquartile range: 4.0-5.9) years. Further, 36 (51.4%) children stopped wearing contact lenses; among them, 17 (47.2%) stopped within 3 months, and the median duration of lens wearing was 4.0 (interquartile range: 1.0-11.5) months. Additionally, there was a correlation between the duration of lens wearing and lens abandonment (r = -0.698, P < 0.001). A high parental education level (hazard ratio [HR] = 0.425; 95% confidence interval [CI] 0.198, 0.913; P = 0.028) was a protective factor against lens abandonment, while parental assessment indicating harder than expected practicality (HR = 4.062; 95% CI 1.204, 13.707; P = 0.024) was a risk factor for abandonment. CONCLUSION: Children aged < 6 years are susceptible to early discontinuation of RGPCL use. Since parents perform daily lens manipulation, they are crucial to the continuity of lens use in these children. To improve RGPCL use continuity, communication and supervision should be strengthened before and after RGPCL fittings.

Effect of owner presence on healing of spontaneous chronic corneal epithelial defects after anterior stromal puncture.

OBJECTIVE: To examine the effect of client presence on healing rates of spontaneous chronic corneal epithelial defect (SCCEDs) following debridement and anterior stromal puncture (ASP). ANIMALS STUDIED: Sixty-eight client-owned dogs. PROCEDURES: Dogs presenting prior to the COVID-19 shutdown were assigned to the C group (client in the room, 31/68), while dogs presenting after were assigned to group NC (no client in the room, 37/68). Inclusion criteria were retention of fluorescein, non-adherent epithelium, persistence for at least 1 week, and recheck within 1 month. Exclusion criteria were concurrent ocular disorders and endocrinopathies. Success was defined as negative fluorescein retention at first recheck. t-Tests, rank-sum tests, and chi-squared or Fisher's exact tests were used to compare findings between groups. Logistic regression was used to determine whether odds of success at first recheck differed between groups or were modified by other characteristics. RESULTS: Dogs in the NC group were older (9.9 vs. 8.7 years, p = .014) and had more bandage contact lenses (BCLs) placed (65% vs. 29%, p = .003). There were no other significant differences between groups. BCL placement was associated with significantly greater odds of healing by first recheck (OR = 4.00, 95% CI: 0.63-11.2; p = .008). The NC group initially had 2.5 times greater odds of healing than the C group; after adjusting for BCL placement, the association between client location and healing weakened (aOR = 1.80, 95% CI: 0.63-5.13; p = .277). CONCLUSIONS: Healing was marginally associated with not having the client in the room, likely due to increased BCL use. BCL application improves SCCED healing rates following debridement/ASP.

International trends in prescribing silicone hydrogel contact lenses for daily wear (2000-2023): An update.

PURPOSE: Introduced around the turn of the 21st century, silicone hydrogel contact lenses alleviated hypoxic anterior eye complications due to their high oxygen transmissibility. The purpose of this work is to update earlier surveys by describing international trends in silicone hydrogel daily wear contact lens fitting between 2000 and 2023. METHOD: An annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023. Data relating to 260,144 daily wear soft contact lens fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of silicone hydrogel daily wear contact lens fitting. RESULTS: There has been a dramatic increase in silicone hydrogel daily wear lens fits (p < 0.0001), increasing from 2.8 % of all daily wear soft lens fits in 2000 to 73.7 % in 2023. Of all daily wear soft contact lenses prescribed to males, 44.6 % were silicone hydrogel lenses, compared with 43.5 % for females (p = 0.0146). The mean age of those wearing silicone hydrogel daily wear lenses was 32.0 ± 14.5 years, compared to 30.4 ± 13.6 years for those wearing daily wear hydrogel lenses (p < 0.0001). Between 2019-2023, the average percentage of fits was - (a) material type: silicone hydrogel - 73 %; mid-water content hydrogels - 13 %; high water content hydrogels - 9 %; and low water content hydrogels - 5 %, and (b) lens design: spherical - 44 %, toric - 32 %, multifocal - 17 %, monovision - 4 %, and 'other' - 3 %. CONCLUSION: The dramatic increase in silicone hydrogel contact lens prescribing for daily wear has been commensurate with the introduction of multiple lens brands and an ongoing expansion of lens designs, parameters and replacement frequency options. The balance between silicone hydrogel and hydrogel lens prescribing is perhaps starting to approach an equilibrium.

Experimental Study on Ocular Surface Protection by Soft Contact Lenses Due to Volcanic Ash Exposure.

Background: Sudden volcanic eruptions can lead to volcanic ash entering the eyes, causing severe discomfort and complicating evacuation efforts. The specific effects of volcanic ash on ocular tissues, especially when wearing soft contact lenses (SCLs), are not well documented, prompting this experimental investigation. Methods: White rabbits with normal eyes were randomly divided into three groups: (1) a bare eye group: bare eye + volcanic ash exposure + eye washing, (2) an SCL group: SCL-wearing eye + volcanic ash exposure + eye washing, and (3) a control group: eye washing only. In groups 1 and 2, volcanic ash was applied to one eye under topical anesthesia, followed by immediate saline rinsing. Slit-lamp microscopy and histopathological analysis were conducted after euthanasia. Results: Slit-lamp and histopathological examinations revealed more significant corneal and conjunctival erosion in the bare eye group compared to the SCL group, which showed limited damage. The control group displayed no ocular damage. Conclusions: Guidelines from the "Volcanic Ash Health Effects: A Guide for the Public" by the National Research Institute for Earth Science and Disaster Resilience recommend removing SCLs during ashfall. Our findings suggest that the damage to the corneal and conjunctival epithelium is less severe in SCL-wearing eyes than in bare eyes, recommending that SCL wearers prioritize evacuation over lens removal during sudden ashfall.

Analysis of Deposition and Diffusion of Cholesterol in Silicone Hydrogel Contact Lenses Using Confocal Microscopy.

In this study, we investigated lipid deposition and diffusion in silicone hydrogel (Si-Hy) contact lenses using confocal microscopy. Different Si-Hy lenses were analyzed to understand the interaction patterns of cholesterol with various lens materials. The results highlight significant differences in the deposition and diffusion of lipids through the lenses, revealing that some materials, such as comfilcon A, allow lipids to diffuse more freely compared to others, such as samfilcon A, which provides a greater barrier. The study also observed different morphology and movement of lipid agglomerates across the lenses and above it surfaces. These findings contribute to the understanding of lipid-lens interaction, which is important for the development of lenses with improved comfort and functionality. The research highlights the importance of considering lipid interactions in the design and selection of Si-Hy contact lenses to enhance wearer comfort and lens performance.

Interaction of retinal electrophysiology and novel orthokeratology lens use on myopia control efficacy in children.

AIMS: The relationship between retinal electrophysiological function and myopia progression was evaluated in school-aged children wearing Breath-O-Correct Orthokeratology (OK) lenses compared with those wearing single vision (SV) lenses over 24 months. METHODS: In this randomised, single-blind, parallel controlled trial, children aged 8-12 years with -1.00 to -4.00 D of myopia were recruited. Retinal function was evaluated using global-flash multifocal electroretinography at baseline before OK or SV treatment. Axial length was evaluated at 6-month intervals up to 24 months. The main outcome measures were axial elongation (AE) between groups and the interactive effect of baseline retinal function. RESULTS: A total of 70 children (43 OK, 9.8±1.3 years; 27 SV, 9.5±1.4 years) completed the 2-year study and were included in the analysis. The 2-year normalised AE was 0.37±0.37 mm in the OK group and 0.60±0.41 mm in the SV group, respectively. For children in the SV group, the amplitude of the central inner retinal response was negatively correlated with axial length elongation (p=0.03). In contrast, this relationship between retinal electrophysiology and AE was not observed in OK group, indicating that they were independent of each other in children treated with OK (p=0.33). CONCLUSION: A weak retinal electrophysiological response was a risk factor for rapid AE in SV controls. However, OK treatment can lower this risk factor and significantly reduce AE in school-aged children.

Contact Lens-Related Corneal Infections.

Our review provides an update on the current landscape of contact lens-associated microbial keratitis (MK). We discuss the prevalence and risk factors associated with MK, emphasizing the role of overnight wear, poor hygiene, and contact lens type. CL-related MK is commonly caused by bacteria, though can also be caused by fungi or protozoa. Clinical presentation involves ocular pain, redness, and vision loss, with more specific presenting symptoms based on the culprit organism. Treatment strategies encompass prevention through proper hygiene and broad-spectrum antibiotic, antifungal, or antiprotozoal therapy, with surgical management reserved for severe recalcitrant cases.

Microbial Contamination in Contact Lenses, Lens Care Solutions, and Accessories Among Asymptomatic Soft Contact Lens Users.

Objective This study aimed to evaluate microbial contamination of contact lenses (CL) and their accessories among asymptomatic lens users and identify behavioral risk factors that might exacerbate the said contamination. Methodology Ninety-five asymptomatic soft CL users were recruited. In total, 380 samples were collected from the inner surface of lenses, the base of lens cases, the tip of the multipurpose solution bottle, and the solution itself. All swabs with samples were inoculated onto Columbia 5% sheep blood agar, MacConkey agar, Pseudomonas agar with cetrimide, and Sabouraud dextrose agar. Blood agar, MacConkey agar, and Pseudomonas agar with cetrimide were incubated at 37 °C for 24-48 hours. Fungal growth was investigated on Sabouraud dextrose agar, incubated at 25 °C, and examined daily for three weeks. Microscopic examination, culture-based methods, and biochemical tests were used to identify isolated microorganisms. A self-administered questionnaire on compliance with care and hygiene procedures was completed by each participant. Results The overall microbial contamination of tested samples was 38.7%. The most frequently contaminated items were lens cases (59, 62.1%), followed by bottles (44, 46.3%) and lenses (35, 36.8%). Meanwhile, the lowest incidence of contamination was seen in lens multipurpose solutions (9, 9.5%). The predominant microorganisms recovered were Coagulase-negative Staphylococci (CoNS) (94, 64%) and Gram-positive rods (29, 19.7%). Other identified potential pathogens were Staphylococcus aureus (11, 7.5%), Pseudomonas aeruginosa (5, 3.4%), Escherichia coli (1, 0.7%), and Candida albicans (2, 1.4%). The questionnaire revealed that contact lens users aged 18 to 20 showed a lack of compliance with proper hygienic care for contact lens maintenance. Risk factors such as male gender, smoking, showering, or swimming while wearing CL were related to microbiological contamination in at least one of the samples (P > 0.05). Conclusions The highest degree of contamination with highly virulent pathogens was determined in lens cases owing to insufficient lens care practices among study participants. Noncompliance with the lens cleaning procedures can lead to microbial colonization of the lens and its accessories, prompting inflammatory events in the eyes in the future.