Corneal Nerve, Dry Eye Disease, Tear Film
Conditions
Keywords
dry eye, tear film
Brief summary
Diabetes mellitus has been associated with ocular surface damage and exacerbates dry eye disease (DED) pathology. To investigate clinical and inflammatory changes in the ocular surface of insulin-independent type II diabetic patients. This cross-sectional control study will recruit 200 Type 2 diabetic patients and 200 age- and sex-matched subjects without DM.
Detailed description
Diabetes mellitus (DM) is a developing global health challenge due to the multiple complications associated with long-term hyperglycemia. Although diabetic retinopathy is the most prevalent and well-known ophthalmic consequence, diabetes also causes clinically significant effects on the ocular surface. Among the ocular surface diseases, dry eye disease (DED) is the most common. Multiple mechanisms, such as ocular surface and lacrimal gland inflammation, neurotrophic deficiency, and meibomian gland dysfunction (MGD), play significant roles. A loss of tear film homeostasis characterizes DED. DM is one of the risk factors for DED; 47% of DM patients suffer from ocular surface damage due to negative alterations to the tear film, corneal thickness, corneal epithelium, corneal nerve, and corneal endothelium. It has been suggested that one or more of the following initial events may lead to alterations described in the tear film and ocular surface of patients with DM: a) chronic hyperglycemia, b) corneal nerve damage, and c) impairment on insulin action. Previous studies have explored the association between DM and ocular surface dysfunction. However, ocular surface and tear film parameters in diabetic patients are lacking in the Chinese population. Moreover, corneal nerve damage and ocular surface inflammation have not been systematically evaluated. Our study aimed to investigate clinical and inflammatory changes in the ocular surface of insulin-independent type II diabetic patients in a Chinese population.
Interventions
None listed
Sponsors
He Eye Hospital
Study design
Observational model
OTHER
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* Participants are diagnosed with dry eye according to the TFOS DEWS II diagnostic criteria: (a) OSDI questionnaire ≥13, (b) Non-invasive tear breakup time (NITBUT) \<10 s, (c) ocular surface staining \>5 corneal spots, greater than nine conjunctival spots (The presence of two or more criteria was used to establish a positive DE diagnosis). * Age ≥ 18
Exclusion criteria
* Active ocular infection, such as infectious, viral, chlamydial, or immunologic conjunctivitis * A history of ocular surgery that might affect the corneal or tear film, such as corneal refractive surgery, keratoplasty, cataract surgery, or ocular laser surgery * Long-term contact lens wear * Other ocular diseases being treated might affect the corneal or tear film: such as glaucoma, dacryocystitis, uveitis, and pterygium.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| MMP-9 | Baseline | MMP-9 was measured using an immunochromatography assay by collecting 1ul tear samples from the lateral canthus using a capillary tear collector. To assess the concentration of MMP-9 in the tear samples, a commercial reagent card (S05B, Seinda Biomedical Corporation, Guangdong, China) based on colloidal gold and immunochromatographic analysis was utilized. 1ul tear sample was placed in the sampling hole on the reagent card, followed by three drops of diluent in the dilution hole. The reagent card was loaded into the proprietary analyzer, and 15 minutes later, the MMP-9 concentration was measured |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Conjunctival hyperemia (RS score) | Baseline | Conjunctival hyperemia (RS score) will be assessed by keratograph image (Oculus, Germany) of 1156\*873 pixels, redness score (RS) (accurate to 0.1 U) was displayed on the computer screen |
| Quality of meibum grade | Baseline | Meibum quality will be assessed under a slit-lamp: Five meibomian gland in the middle parts of the eyelid will be assessed using a scale of 0 to 3 for each gland (0 represented clear meibum; 1 represented cloudy meibum; 2 represented cloudy and granular meibum; and 3 represented thick, toothpaste like consistency meibum). |
| Expressibility of meibum grade | Baseline | Meibum expressibility will be assessed under a slit-lamp: Eight meibomian glands in the middle part will be evaluated on a scale of 0 to 3 (0 denoted that all glands expressible; 1 denoted that 3 to 4 glands expressible; 2 denoted those 1 to 2 glands expressible; and 3 denoted that no glands were expressible). The overall score was computed using the mean scores of these eight glands. |
| Conjunctivocorneal epithelial staining grade | Baseline | Conjunctivocorneal epithelial staining will be assessed under a slit-lamp: Conjunctivocorneal epithelial staining will be assess corneal and conjunctival epithelium damage. Double vital staining approach with two microliters of a preservative-free solution containing 1% lissamine green and 1% sodium fluorescein will be instilled in the conjunctival sac. The eye will be sectioned into three equal pieces (temporal conjunctiva, cornea, and nasal conjunctiva). Each region receives a maximum staining score of three points and a minimum of zero points. The combined scores from all three parts were then recorded on a scale ranging from 0 (normal) to 9 (severe) |
| Tear Film Lipid Layer | Baseline | Tear Film Lipid Layer interferometry will be assessed using DR-1 (Kowa, Nagoya, Japan). |
| OSDI Score | Baseline | Chinese translated, and validated OSDI (Allergan Inc, Irvine, USA) version will beused to assess and quantify DE symptom. The 12 items of the questionnaire can be tabulated into a score that ranges from 0 (no symptoms) to 100 (severe symptoms) points |
| Non-invasive tear break-up time | Baseline | Changes in non-invasive initial tear film breaking time will be assessed using the Keratograph 5M (Oculus, Germany) topographer. Three sequentially readings will be captured, and the median value will be included in the final analysis. The median value will be recorded. |
| Corneal nerves and immune/inflammatory cells change | Baseline | HRT III RCM, (Heidelberg Engineering GmbH, Dossenheim, Germany) will be used to record corneal nerves and immune/inflammatory cells change. |
| Retinal morphology | Baseline | A scanning laser ophthalmoscope (TRC-NW300, Topcon, Tokyo, Japan) will be used to examine and record the retinal morphology, and deep learning software will be used to analyze the vascular changes of the subjects. |
| Central corneal sensitivity | Baseline | Central corneal sensitivity will be measured using a Cochet-Bonnet esthesiometer (Luneau Technology Operations, France), which stimulates the cornea with a nylon monofilament. The stiffness of the filament is adjusted by altering the length (0-6cm) of the filament with a slider on the side of the pen |
| Corneal endothelium | Baseline | Corneal endothelium of all patients will be photographed by contactless specular microscopy (SM) device (EM-4000; Tomey Corporation, Japan) by the same observer. The unit of cell density was evaluated as mm2 |
| Thermal imaging: Ocular surface temperature (OST) | Baseline | All measurements were taken in the same room with controlled temperature and humidity. Prior to ocular thermography or other tests, participants were acclimatized to the room for 20 minutes. Morgan and colleagues described the following criteria for recording OST: The patients were instructed to blink normally, close their eyes for 3 seconds, and the first image was captured soon after the eyelids opened. The temperature was taken in the central cornea, which was defined as a circular area 4 mm in diameter in the middle of the cornea |
| Tear meniscus height (TMH) | Baseline | Non-invasive first tear film breakup time using the Keratograph 5M (Oculus, Germany) topographer will be measured three times consecutively and the median value was recorded |
Countries
China
Contacts
Primary ContactGuanghao Qin
Outcome results
None listed