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Tear dynamics under scleral lenses
- Source :
- Contact lens & anterior eye : the journal of the British Contact Lens Association, vol 42, iss 1
- Publication Year :
- 2018
-
Abstract
- Purpose To evaluate post-lens tear dynamics at two different time points during scleral lens wear in two cohorts with 10 neophytes each. Methods All subjects wore bilaterally scleral lenses for 5 h on 3 separate visits. Post-lens tear exchange was measured using Out-in method, which required 5 μL of 2% FITC-Dextran instilled on the bulbar conjunctiva during lens wear. Time taken to observe the first sign of fluorescence in post-lens tear reservoir was recorded with a stopwatch. Out-in measurements were collected at 5-hour post-lens insertion in Group 1 and compared with those obtained at 20 min of lens wear in Group 2. Tear dynamics under the lens was observed in Group 2 with fluorogram using a modified slit-lamp technique (Tan et al., 2018) to monitor post-lens fluorescence intensity and with high-resolution spectral domain optical coherence tomography (ENVISU 2300; Bioptigen Inc.) to measure post-lens tear thickness (PoLTT) over 5 h of lens wear. Results 60% of subjects in Group 1 achieved Out-in times less than 5 min at 5-hour post-lens insertion, compared with 67% of subjects at 20-min lens wear (Tan et al., 2018). Using qualitative analysis on 60 series of data in Group 2 to compare the changes in fluorescence intensity and PoLTT with respect to lens-wearing time, 27% was due to lens settling, 13% was due to tear exchange and mixing while 60% indicated tear dynamics under scleral lenses was due to a combination of tear exchange, mixing, and lens settling. Conclusion Tear flow into tear reservoir under a scleral lens on subjects with healthy cornea occurred at 20 min and 5 h after lens insertion. After 5 h of lens wear, roughly one third of the subjects had no tear flow into post-lens reservoir, as the observed decline in post-lens tear fluorescence was predominately due to lens settling.
- Subjects :
- Male
Hydrophilic
Ophthalmology & Optometry
Tear mixing
law.invention
Cornea
0302 clinical medicine
law
Prospective Studies
Fluorescein Angiography
Fluorogram
Tomography
Cross-Over Studies
Dextrans
General Medicine
Contact Lenses, Hydrophilic
Lens (optics)
Fluorescence intensity
medicine.anatomical_structure
Bulbar conjunctiva
Female
Fluorescein
Fluorescein-5-isothiocyanate
Sclera
Tomography, Optical Coherence
medicine.medical_specialty
Materials science
Contact Lenses
Scleral lens
Spectral domain
Tear exchange
03 medical and health sciences
Young Adult
Qualitative analysis
Double-Blind Method
Opthalmology and Optometry
Ophthalmology
medicine
Humans
eye diseases
OCT
Optical Coherence
Tears
030221 ophthalmology & optometry
sense organs
030217 neurology & neurosurgery
Optometry
Subjects
Details
- ISSN :
- 14765411
- Volume :
- 42
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- Contact lensanterior eye : the journal of the British Contact Lens Association
- Accession number :
- edsair.doi.dedup.....12f4f03072459c264de3258c991c39c0