Cessation Of Contact Lens Wear Research Articles

Short-term changes in topometric indices after discontinuation of rigid gas permeable lens wear in keratoconic eyes.

Purpose:To estimate the time taken for topometric indices to stabilize in keratoconic corneas following cessation of habitual RGP contact lens wear.Methods:A total of 29 eyes of 20 patients, diagnosed with mild to severe keratoconus were included in this prospective observational study. All patients were experienced RGP contact lens wearers (either conventional RGP or Rose K2 lens) with each patient having used these lenses for at least a year. Corneal topography was performed immediately following discontinuation of habitual contact lens wear at baseline and each of four consecutive visits, 1-week apart.Results:An overall reduction in the keratometry and thickness values were noted on tomography immediately following cessation of contact lens wear and these indices increased significantly in the 1st week (P < 0.001). Consecutive visits following the first visit did not show any significant change in the topometric parameters (P > 0.05). Subgroup analysis revealed a similar trend in eyes with “severe” keratoconus and in eyes fitted with the “three-point touch” philosophy. However, eyes with “mild-moderate” keratoconus and those fitted with “apical clearance” fitting philosophy showed marginal differences even within the 1-week period of lens cessation.Conclusion:Maximum changes in keratometry and pachymetry values following discontinuation of RGP lens wear stabilize within the 1st week of cessation of rigid lens wear in a keratoconic cornea. These changes were more pronounced in patients with severe keratoconus and those with an apical bearing fit. This information would be useful for practitioners to assess the progression of keratoconus in RGP lens users before collagen cross-linking.

Contact Lens Induced Limbal Stem Cell Deficiency: Clinical Features in Korean Patients.

PurposeTo describe the clinical features of Korean patients with contact lens-induced limbal stem cell deficiency (CL-LSCD).MethodsMedical records of 22 patients who were diagnosed with CL-LSCD between 2014 and 2019 were reviewed retrospectively. Outcome measures included demographics, clinical presentation, treatment, clinical course, and pattern of contact lens (CL) wear.ResultsForty-two eyes of 22 patients were found to have typical changes associated with CL-LSCD. Twenty (91%) patients were women and mean age was 36 ± 12 years. All patients had myopia with mean spherical equivalent of −7.52 ± 3.2 diopter. Twenty (91%) patients had bilateral disease and the location of limbal involvement was diffuse in 20 eyes (47.6%) and partial in 22 eyes (52.4%, superior in 20 eyes and inferior in 2 eyes). Fourteen (63.6%) patients complained of decreased visual acuity. Average period of CL wear was 14 ± 9 years. Four patients used cosmetic colored CLs and four patients had a history of overnight CL wear. All 12 patients who completed follow-up (28 ± 42 weeks) showed improvement in visual acuity and ocular surface condition after cessation of CL wear and medical treatment. Of them, five (42%) patients showed full recovery while seven (58%) showed partial recovery.ConclusionsIf a patient with a history of CL wear for an extended period of time presents with decreased visual acuity, practitioners should perform detailed examinations with suspicion of CL-LSCD, including fluorescein staining. CL-LSCD is usually reversible and close follow-up with conservative treatment is recommended as the initial treatment option.

Recovery Evaluation of Induced Changes in Higher Order Aberrations From the Anterior Surface of the Cornea for Different Pupil Sizes After Cessation of Corneal Refractive Therapy

To assess corneal aberration changes induced by corneal refractive therapy (CRT) for different pupil sizes and to examine the recovery after cessation of contact lens wear. A single-center, prospective, and longitudinal study was performed. Thirty-four subjects who underwent CRT for 1 year were included. High-contrast corrected distance visual acuity (CDVA), manifest refraction, and corneal topography were determined during the treatment and 1 month after the discontinuation of the treatment. Corneal aberrations were calculated using the Vol-CT 6.89 software. Corneal spherical aberration, Z(4,0), and root mean square values (RMS) for coma-like, trefoil, tetrafoil, and higher order aberrations (HOAs) were estimated for different pupil sizes (3-, 4-, 5-, 6-, and 7-mm diameters). Early Treatment Diabetic Retinopathy Study charts were used to measure CDVA. The CRT treatment induced a statistically significant increase of all aberrations studied for all pupil diameters. RMS values for coma-like, trefoil, and tetrafoil aberrations and HOAs after cessation of contact lens wear were not statistically significantly different for any of the different pupil diameters studied at baseline. However, Z(4,0) significantly increased from baseline to 1 month after discontinuation of the CRT lens wear for 5-, 6-, and 7-mm diameter pupils. Our results suggest that CRT is a treatment completely reversible at 1 month after cessation of contact lens wear in terms of CDVA, refractive error, and RMS of coma-like aberrations and HOAs for all pupil sizes. However, for spherical aberration, 1 month is not enough to recover to the baseline level.

Biomechanical properties in corneal refractive therapy during adaptation period and after treatment interruption: A pilot study

PurposeTo evaluate the potential influence and treatment-related changes of the corneal biomechanical properties (BMP) measured with the Ocular Response Analyzer (ORA, Reichert, Depew, NY) 15-days and 1-month after the initiation and cessation of corneal refractive therapy (CRT). MethodsTwenty-four young healthy subjects (24.04±3.19 years) participated in two different experiments. In the first one (#1), twelve right eyes from 12 subjects who were fitted with CRT lenses were evaluated after 15 days and 1 month of lens wear. In the second trial (#2) 12 subjects who had been wearing CRT lenses for a period of 1 year were evaluated at 15 days and 1 month after treatment interruption. ResultsThere was no statistically significant correlation between baseline BMP and absolute values of structural corneal parameters at 15 and 30 days treatment, and also when these variables were normalized according to the targeted refraction. In experiment #1, Corneal hysteresis (CH) reduction was observed over the time of treatment (p=0.019), but no significant differences were observed in the Corneal Resistance Factor (CRF) values. In addition, CRF reduction significantly correlated with spherical equivalent refraction (r=0.597; p=0.044), but no correlation was observed between CH or CRF reduction and the spherical component of the refraction. In experiment #2, no significant changes in CH or CRF were found initially after lens wear interruption, but a trend to increase was observed thereafter. ConclusionCH decreases during onset of the CRT after 30 days of lens wear. Such changes seem to be reversible after cessation of contact lens wear following 1 year of treatment. Corneal biomechanics, however, do not predict the outcomes of CRT in clinical setting although with the data obtained some correlative tendencies were observed that may merit further investigation.

Laser In Situ Keratomileusis Treatment for Myopia in a Patient With Partial Limbal Stem Cell Deficiency

The authors report a patient with soft contact lens-induced partial corneal limbal stem cell deficiency who successfully underwent laser in situ keratomileusis (LASIK) for correction of myopia. A 23-year-old man with a 6-year history of daily soft contact lens wear developed partial limbal stem cell deficiency of both corneas. The corneal disease resolved with cessation of contact lens wear and topical corticosteroid treatment. LASIK was performed in both eyes 1 year later. The patient successfully underwent LASIK and achieved an uncorrected visual acuity of 20/15 in both eyes. No complications were observed intraoperatively or postoperatively. The cornea and refraction remained stable 3 months postoperatively. In this patient with partial limbal stem cell deficiency secondary to soft contact lens wear, LASIK was a viable and safe alternative for the correction of myopia.

Evaluation of the pre-lens tear film forming on three disposable contact lenses.

The most common cause of complaint from contact lens wearers is that of dryness. This induces discomfort, reduced wearing time and is one of the reasons of cessation of contact lens wear. The reduced comfort is caused by evaporation of the prelens tear film, leading to surface dehydration and loss of tear fluid from the lens matrix. This fluid flow towards the surface produces pervaporation staining which is commonly seen in patients presenting with symptoms of dryness. The lens surface with reduced tear coverage is prone to increased protein deposition thus reducing the effective life of the contact lens. The most common solution to those problems has been to fit thicker lenses to limit pervaporation staining or to accelerate the rate of replacement of disposable lenses to limit the effect of surface deposits. This is of limited use for patients with poor tear films who experience discomfort at the outset and can only wear lenses for 2 to 3 hours. The aim of the study was to study the prelens tear film structure of three monthly disposable contact lenses and to find out if it supported an adequate superficial lipid layer as it would forms a barrier to evaporation.

Effects of laser in situ keratomileusis (LASIK) on the corneal endothelium 3 years postoperatively

PURPOSE: To investigate the effects of laser in situ keratomileusis (LASIK) on the corneal endothelium 3 years postoperatively. METHODS: Patients who were subjects of a previous prospective study (Am J Ophthalmol 125:465–471, (April) 1998) were contacted for a follow-up analysis of the central corneal endothelium. Noncontact specular microscopy was performed 35 to 37 months after LASIK on 52 eyes of 27 patients of the original cohort of 98 eyes of 65 patients and six eyes of three patients who were previously lost to follow-up after their initial post-LASIK evaluation. Patient age ranged from 29 to 66 years at the time of the original LASIK procedure. Attempted corrections ranged from 2.25 to 14.5 diopters of myopia, giving theoretical ablation depths of 182 to 332 μm below the corneal surface. Forty-eight eyes (83%) had a history of preoperative contact lens use (3 to 33 years). Central endothelial cell density, coefficient of variation of cell size, and percent of hexagonal cells were analyzed using 72 to 152 cells from each image. Multivariate analysis was used to search for factors that might predict changes in cell density, coefficient of variation, and percent of hexagonal cells. RESULTS: The mean ± SD preoperative cell density was 2,498 ± 354 cells per mm 2, the mean coefficient of variation was 0.36 ± 0.07, and the percent of hexagonal cells was 58 ± 6. Three years after surgery there was no statistically significant change in the mean endothelial cell density (2,489 ± 335 cells per mm 2; P = 0.88, paired t test) or the percent of hexagonal cells (60 ± 7; P = 0.14, paired t test). The mean coefficient of variation was significantly lower postoperatively (0.32 ± 0.04; P = 0.0006, paired t test); a repeated measures analysis showed that this significant improvement could not be explained by cessation of contact lens wear after LASIK ( P = 0.34). Multivariate analysis did not identify any factors that were predictive of change in cell density, coefficient of variation, and percent of hexagonal cells. CONCLUSIONS: Laser in situ keratomileusis for the correction of 2.25 to 14.5 diopters of myopia had no significant effect on central corneal endothelial cell density or the percent of hexagonal cells 3 years after surgery. The coefficient of variation of cell size improved significantly 3 years after surgery.

The Effect of Photorefractive Keratectomy on the Corneal Endothelium

The authors prospectively investigated the effect of excimer laser photorefractive keratectomy (PRK) for myopia on the corneal endothelium. Quantitative computer-assisted morphometric analysis of central and peripheral corneal endothelial cells was performed on 142 myopic eyes before and at 3 months, 1 year, and 2 years after PRK. The mean age of the subjects was 37 years (range, 21-66 years). Ninety-one (64%) of them had a history of contact lens wear. Mean attempted correction was -3.9 diopters (range, -1.6 to -6.0 diopters). The mean preoperative endothelial cell density was 2660 cells/mm2 centrally and 2776 cells/mm2 peripherally. There was no change in central endothelial cell density at any of the postoperative examinations. The peripheral cell density decreased 4.1% (P = 0.003) at 3 months and 6.2% (P = 0.0001) at 1 year. However, the peripheral cell density was not significantly different from the preoperative value at 2 years. The peripheral coefficient of variation of cell size was 7.8% lower 2 years postoperatively than it was preoperatively, and this improvement was attributable to cessation of contact lens wear after PRK. The decrease in peripheral endothelial cell density at 1 year correlated with the amount of attempted correction, but there was no correlation between attempted correction and the change in central or peripheral endothelial cell density 2 years postoperatively. For the correction of up to 6.0 D of myopia, PRK causes no detectable changes in central corneal endothelial cell density, but it does cause a transient, modest loss of peripheral corneal endothelial cells at 1 year. Variations in endothelial cell shape caused by contact lens wear resolve after PRK.

Disposable Soft Contact Lens Ulcers

We report an outbreak of 43 episodes of presumed microbial keratitis in 42 disposable soft contact lens wearers seen in the Accident Room of Manchester Royal Eye Hospital during a period of 20 months, and compare this with the general incidence of contact lens-related corneal infection found in a retrospective survey of 6 months' Accident Room attendances during the same period. Thirty-seven patients had worn Acuvue lenses, three had worn Nuvue, and there was no record in two cases. Corneal scrapes were taken for microbiological examination in 27 patients, and 6 of these were culture positive. Conjunctival swabs were taken from eight eyes and one was culture positive. The contact lenses of 11 patients were sent for culture and all grew pathogenic organisms. Pseudomonas spp. were the most common organisms grown, having been found in three of six corneal scrapes and six of 11 contact lens cultures. All affected eyes responded promptly to cessation of contact lens wear and topical antibiotic therapy, with none sustaining severe or permanent visual loss. Reasons for the associated high risk of microbial keratitis are discussed. Thirty-three of the 42 patients responded to a questionnaire regarding lens wear and care and their responses are reported. In consequence, we consider disposable soft contact lenses to be relatively high-risk devices for the cosmetic management of simple myopia, and their continued use must be called into question.

Specular microscopy studies on the corneal endothelium after cessation of contact lens wear: by M.E. Sibur, M.B. Datiles, K. Kashima, et al. Cornea 10:395–401, 1991

Specular microscopy studies on the corneal endothelium after cessation of contact lens wear: by M.E. Sibur, M.B. Datiles, K. Kashima, et al. Cornea 10:395–401, 1991

Topographic Changes in Contact Lens-induced Corneal Warpage

Twenty-one eyes of 12 patients with contact lens-induced corneal warpage were followed prospectively using computer-assisted topographic analysis. Sixteen eyes had worn rigid contact lenses (13 eyes, polymethylmethacrylate; three eyes, gas-permeable), and five eyes had worn soft contact lenses. Initial corneal topographic patterns were characterized by the presence of central irregular astigmatism, loss of radial symmetry, and frequent reversal of the normal topographic pattern of progressive flattening of corneal contour from the center to the periphery. A correlation was noted between the initial corneal topography and the resting position of the contact lens on the cornea for nine of the 16 eyes with rigid contact lenses. Initial topography for each of these corneas showed relative flattening of the corneal contour underlying the resting position of a decentered contact lens. Superior-riding lenses produced a topography that simulated early keratoconus. After cessation of contact lens wear, 16 of 21 eyes had a change in corneal shape to a topography that was consistent with a normal pattern. Five corneas stabilized with an abnormal topographic pattern. A much longer time without contact lenses than had been previously reported, up to 5 months, was required for a return of a stable corneal topography in eyes with contact lens-induced corneal warpage caused by rigid lenses.

Contact lens wear is associated with the appearance of plasmin in the tear fluid — preliminary results

We determined biochemically the plasmin concentration in tear fluid from 50 externally healthy eyes and from 49 eyes during contact lens (CL) wear. After cessation of CL wear, samples were collected again from 41 of the 49 eyes. Plasmin was detected more frequently (P less than 0.0001) in the CL-wearing group (75.5%) than in the control group (20%). After the cessation of CL wear (3-21 days), the frequency of plasmin detection in tear fluid decreased significantly (P less than 0.0006) but was still higher (39%) than in the control group. We conclude that the occurrence of plasmin in tear fluid is correlated with CL wear. The proteolytic activity of plasmin may contribute to the development of corneal epithelial pathology associated with CL wear.