Instillation Of Artificial Tears Research Articles

Effectiveness of Nonpharmacologic Treatments for Acute Seasonal Allergic Conjunctivitis

To investigate whether artificial tears and cold compress alone or in combination provide a treatment benefit and whether they were as effective as or could enhance topical antiallergic medication. Randomized, masked clinical trial. Eighteen subjects (mean age, 29.5±11.0 years) allergic to grass pollen. Controlled exposure to grass pollen using an environmental chamber to stimulate an ocular allergic reaction followed by application of artificial tears (ATs), 5 minutes of cold compress (CC), ATs combined with CC, or no treatment applied at each separate visit in random order. A subset of 11 subjects also had epinastine hydrochloride (EH) applied alone and combined with CC in random order or instillation of a volume-matched saline control. Bulbar conjunctival hyperemia, ocular surface temperature, and ocular symptoms repeated before and every 10 minutes after treatment for 1 hour. Bulbar conjunctival hyperemia and ocular symptoms decreased and temperature recovered to baseline faster with nonpharmaceutical treatments compared with no treatment (P <0.05). Artificial tears combined with CC reduced hyperemia more than other treatments (P <0.05). The treatment effect of EH was enhanced by combining it with a CC (P <0.001). Cold compress combined with ATs or EH lowered the antigen-raised ocular surface temperature to less than the pre-exposure baseline. Artificial tear instillation alone or CC combined with ATs or EH significantly reduced the temperature (P <0.05). Cold compress combined with ATs or EH had a similar cooling effect (P >0.05). At all measurement intervals, symptoms were reduced for both EH and EH combined with CC than CC or ATs alone or in combination (P <0.014). After controlled exposure to grass pollen, CC and AT treatment showed a therapeutic effect on the signs and symptoms of allergic conjunctivitis. A CC enhanced the use of EH alone and was the only treatment to reduce symptoms to baseline within 1 hour of antigenic challenge. Signs of allergic conjunctivitis generally were reduced most by a combination of a CC in combination with ATs or EH.

Noninvasive, Objective, Multimodal Tear Dynamics Evaluation of 5 Over-the-Counter Tear Drops in a Randomized Controlled Trial

To assess the ability of a noninvasive, objective, multimodal system to compare the efficacy and optical quality of 4 different groups of 5 over-the-counter tear drops. Wavefront sensing and optical coherence tomography (OCT) were used to objectively assess visual quality and tear volume, respectively, after the over-the-counter tear drops [2 polyethylene glycol (PEG)-400, 1 carboxymethyl cellulose (CMC), 1 polyvinyl alcohol/PEG-400 (PVA), and 1 glycerine/polysorbate-80] were administered to 23 patients with aqueous-deficient dry eye in a randomized, controlled, double-masked trial. Measurements at each of the 5 visits were taken from both eyes at baseline and 5, 20, and 40 minutes after drop instillation. At 5 minutes after drop instillation, the 2 PEG drops showed significant worsening of visual quality (-128.87%, P = 0.001) compared with CMC, PVA, and glycerine drops. Tear volume was elevated significantly with PEG and CMC drops at 5 minutes (+33.2%, P = 0.002; +29.9%, P < 0.001) compared with the other groups. Subjects with a Schirmer score of less than 5 mm at 5 minutes showed improvement in visual quality with PEG drops, whereas those with a fluorescein staining score of 1 to 2 showed improvement with both PEG and CMC drops. A trend toward decreasing visual quality with increasing tear meniscus was noted. Noninvasive multimodal imaging has the potential to evaluate tear dynamics and the efficacy of artificial tears objectively. Certain artificial tear components and the temporary increase in tear volume after instillation of artificial tears may contribute to transient reduction of visual quality.

Serial Measurement of Tear Meniscus by FD-OCT After Instillation of Artificial Tears in Patients With Dry Eyes

To use Fourier-domain optical coherence tomography (FD-OCT) to study the effect of artificial tears on the tear meniscus in patients with dry eyes. The lower tear meniscus of 16 consecutive patients with dry eyes was imaged by an FD-OCT system (RTVue; Optovue, Inc., Fremont, CA). Baseline and five serial pairs of measurements were taken after the instillation of artificial tears (Optive; Allergan, Irvine, CA) at 1, 2, 5, 10, and 15 minutes. The lower meniscus height, depth, and area were measured with a computer caliper. Baseline meniscus measurements were 235.5 ± 150.0 μm, 138.1 ± 78.7 μm, and 0.020 ± 0.022 mm(2) for height, depth, and area, respectively. After instillation of artificial tears, all lower tear meniscus parameters remained significantly elevated for 5 minutes and returned to baseline by 10 minutes. FD-OCT is able to quantify a dramatic initial increase in tear meniscus, followed by a decay back to baseline values after approximately 5 minutes. FD-OCT may be useful in objectively quantifying the dynamic efficacy of dry eye treatments.

The Tear Film and the optical Quality of the Eye

The stability of the tear film plays an important role in the optical quality of the eye. Various methods have been developed to quantify the contribution of the tear film to optical quality, including the double-pass optical method, Hartmann-Shack wavefront sensing, videokeratoscopy, retroillumination analysis, and interferometry. In addition to assessing the effect of tear film irregularities, these methods can aid in the diagnosis of dry-eye related conditions and the monitoring of therapy. This review describes the methodologies used to assess the relationship between the tear film and optical quality of the eye and summarizes the most important findings obtained with these methods with regard to the healthy human eye, the dry eye, and the effect of artificial tear instillation.

Watery Eye Following Patent External DCR: An MR Dacryocystography Study

Purpose: To examine patients with persistent watery epiphora following patent external dacryocystorhinostomy (DCR) with magnetic resonance imaging dacryocystography (MR-DCG).Methods: Patients with unobstructed nasolacrimal irrigation following external DCR were included. Five patients with watery epiphora constituted the study group (SG). Five patients without epiphora constituted the control group (CG). All patients underwent MR-DCG following the instillation of artificial tears in the conjunctival fornix. The osteotomy site was identified in T1-weighted coronal images. Lacrimal flow was assessed with modified T2-weighted (True Fast Imaging Steady State Pulse, “TrueFISP”) coronal images before and 10 min after repeated blinking. Signal intensities at three regions of interest (ROIs), corresponding to the eyeball (ROI-1), conjunctival sac (ROI-2), and anastomotic site (ROI-3) were measured.Results: Differences in the diameter of both osseous and soft tissue ostia between SG and CG were statistically not significant. A post-blink increase in signal intensity at ROI-3 was noted in both groups, whereas differences in signal intensity for ROI-1 and ROI-2 were statistically not significant. The post-blink signal intensity increase in ROI-3 was significantly more pronounced in the CG, compared with the SG.Conclusions: The fact that signal intensity increase at ROI-3 was less pronounced in the SG, compared with CG, implies a compromised “lacrimal pump” mechanism in the former group. The methodology presented may be used for the evaluation of post-DCR epiphora.

Optical quality after instillation of eyedrops in dry-eye syndrome

To study the effect of eyedrop instillation on the optical quality of the air-tear film interface at the anterior cornea in cases of dry eye. University of Valencia, Valencia, Spain. Corneal aberrations (total, spherical-like, and coma-like) were determined from corneal elevation maps and purpose-designed software in cases of dry eye before, immediately after, and 10 minutes after lubricating eyedrop instillation (Blink Intensive Tears). All data were decomposed using Zernike polynomials to yield the root-mean-square wavefront deviations for pupil diameters of 3.0 mm and 5.5 mm. Outcome measures included comparison with clinical tear breakup time (TBUT). Wavefront higher-order aberrations (HOAs) decreased significantly, by a factor of 2.5 on average, after artificial tear instillation with both pupil diameters (P<.01). The reduction was maintained 10 minutes after eyedrops instillation (P>.2). The mean TBUT was 3.6 seconds +/- 1.7 (SD). Eyedrop instillation increased the TBUT values significantly (by approximately 60%) from baseline (P<.01). This method of air-tear film interface analysis facilitated evaluation of optical quality improvement after eyedrop instillation in patients with dry eye. After eyedrops were given, the increasingly regular tear film decreased HOAs, improving optical quality.

Dynamic Changes in the Lower Tear Meniscus After Instillation of Artificial Tears

To compare the dynamic changes in lower tear meniscus area (TMA) and height after instillation of artificial tears in patients with dry eye and healthy controls. Twenty-two eyes of 11 patients with dry eye and twenty eyes of 10 age- and sex-matched healthy subjects were included. The inferior tear meniscus height and area measurements were taken before and after instillation of 35 μL carboxymethyl cellulose (CMC) 0.5% and 1.0% (Allergan, Irvine, CA) on 2 consecutive days. The measurements were obtained before and 1, 5, 10, 15, and 30 minutes after instillation using anterior segment optical coherence tomography, RTVue-100 (RTVue, Optovue, Inc). The baseline lower TMA and height in the dry eye group were significantly lower than in the control group. A significant increase in TMA and height was found at 1 minute post instillation of 0.5% CMC in both groups, with findings returning to baseline levels at 5 and 10 minutes post instillation in the control group and dry eye group, respectively. The increase in TMA and height persisted for a longer time period in both groups with 1% CMC, versus 0.5% CMC. At 15 and 30 minutes, both tear meniscus parameters were still significantly higher in the control group and dry eye group, respectively. Artificial tears provide a significant yet temporary improvement in the tear meniscus. The anterior segment optical coherence tomography is valuable to measure dynamic changes in the tear meniscus.

Comparison of the clinical effects of carbomer-based lipid-containing gel and hydroxypropyl-guar gel artificial tear formulations in patients with dry eye syndrome: A 4-week, prospective, open-label, randomized, parallel-group, noninferiority study

Background: Most marketed artificial tears are substitutes for the aqueous layers of the tear film; therefore, frequent instillation of artificial tears is necessary. Newer gel-, cellulose-, and mineral oil-based formulations have been designed to overcome the disadvantages of current aqueous tear substitutes by offering prolonged retention times. Objectives: The aim of this study was to compare the efficacy, safety, and local tolerance of artificial tears containing carbomer-based lipids or hydroxypropyl (HP)-guar gel in patients with dry eye syndrome. Methods: A 4-week, prospective, randomized, parallel-group, comparative, noninferiority study was conducted at the Taipei Medical University Hospital (Taipei, Taiwan) in patients with dry eye syndrome who were randomly assigned to 1 of 2 treatment groups: the carbomer-based lipid-containing (CBLC) gel group and the HP-guar gel group. The primary end point was global assessment of study treatment by the patients at weeks 2 and 4. All patients met the diagnostic criteria of impaired tear function and ocular surface abnormalities. Outcomes measured at baseline and 2 and 4 weeks included Schirmer's test values, tear breakup time (TBUT), and a patient subjective assessment of symptoms. Safety and tolerability were assessed by clinically significant changes in terms of incidence of adverse events and conducted by unmasked investigators. Results: A total of 30 Taiwanese patients with dry eye syndrome were included and randomly assigned to the 2 treatment groups: the mean (SD) age was 40.37 (14.96) years in the CBLC gel group and 49.49 (12.20) years in the HP-guar gel group. At baseline, the mean (SD) Schirmer's test value was 4.53 (2.28) mm in the right eye and 5.13 (2.42) mm in the left eye in the CBLC gel group; 4.40 (2.16) mm in the right eye and 4.20 (1.78) mm in the left eye for the HP-guar gel group. The mean (SD) for both eyes was 4.83 (2.36) mm in the CBLC gel group and 4.30 (2.08) mm in the HP-guar gel group. There was no statistically significant difference between Schirmer's scores at baseline. Patients in both treatment groups experienced an improvement from baseline in symptoms and signs, Schirmer's test value, and TBUT at 2 and 4 weeks after treatment. The Schirmer's test score increased to a mean of 8.20 (4.49) mm in the right eye and 9.33 (4.94) mm in the left eye in the CBLC gel group after 2 weeks, and increased to 10.07 (5.56) mm in the right eye and 10.86 (5.58) mm in the left eye after 4 weeks. The increases in Schirmer's test score and TBUT were also observed in the HP-guar gel group. The Schirmer's test score increased to 5.13 (2.18) mm in the right eye and 5.60 (2.74) mm in the left eye after 2 weeks, and increased to 6.93 (3.37) mm in the right eye and 6.53 (3.16) mm in the left eye after 4 weeks. The increase in Schirmer's test values in both eyes was significantly greater at 2 and 4 weeks in the CBLC gel group than that in the HP-guar gel artificial tear group (all, P < 0.05). Subjective patient assessment was better with the CBLC group (excellent and good reported by 26.6% and 73.4%, respectively, of the CBLC gel group vs 13.4% and 33.4% of the HP-guar gel group at 4 weeks; both, P = 0.004). Conclusions: Both artificial tear formulations were effective in relieving dry eye syndrome in these patients. The tolerance of CBLC gel artificial tears was comparable to that of HP-guar gel artificial tears.

Ultrahigh-Resolution Measurement by Optical Coherence Tomography of Dynamic Tear Film Changes on Contact Lenses

Purpose. To determine the dynamic pre- and postlens tear film (PLTF and PoLTF) thicknesses by using optical coherence tomography (OCT). Methods. Ultrahigh-resolution OCT was used to image the tear film of 22 subjects before and after contact lens wear. A soft lens with 1 drop of artificial tears on its concave surface was inserted onto one randomly selected eye. OCT images were taken before insertion, immediately afterward, and every 2 minutes for 10 minutes. For the contralateral eye, the lens inserted was not prewetted on the concave surface. OCT images were taken before insertion, immediately afterward, and at 3 minutes. Then another drop was instilled, and images were taken immediately afterward and every 2 minutes for 10 minutes. Images were processed by custom software to yield tear film thickness. Results. The thickness of precorneal tear film (PCTF) was 1.9 +/- 0.9 mum. The PoLTF was visualized clearly in all cases immediately after lens insertion, with 1 drop on the lens concave surface. Through the first 6 minutes after insertion, the PoLTF was greater than the PCTF. The PLTF (n = 12) and PoLTF (n = 9) were visualized immediately after lens insertion. After 3 minutes, the PLTF in most subjects and PoLTF in all subjects were invisible. The thickness of the PLTF increased after the instillation of artificial tears, whereas the PoLTF did not at any checkpoint for 10 minutes. Conclusions. Ultrahigh-resolution OCT is a promising tool for measuring the tear film. The PoLTF did not increase after instillation of artificial tears.

In Situ Visualization of Tears on Contact Lens Using Ultra High Resolution Optical Coherence Tomography

To demonstrate the capability of directly visualizing the tear film on contact lenses using optical coherence tomography (OCT). Six eyes of three healthy subjects wearing PureVision and ACUVUE Advance soft and Boston RGP hard contact lenses were imaged with a custom built, high speed, ultra-high resolution spectral domain optical coherence tomograph. Refresh Liquigel was used to demonstrate the effect of artificial tears on the tear film. Ultra high resolution images of the pre- and post-lens films were directly visualized when each lens was inserted onto the eye. After the instillation of artificial tears during lens wear, the tear film was thicker. The post-lens tear film underneath the lens edge was clearly shown. Interactions between the lens edges and the ocular surface were obtained for each of the lens types and base curves. With a contrast enhancement agent, tear menisci on the contact lenses around the upper and lower eyelids were highlighted. With hard contact lenses, the tear film was visualized clearly and changed after a blink when the lens was pulled up by the lid. Ultra-high resolution OCT is a potentially promising technique for imaging tears around contact lenses. This successful demonstration of in situ post-lens tear film imaging suggests that OCT could open a new era in studying tear dynamics during contact lens wear. The novel method may lead to new ways of evaluating contact lens fitting.

Effect of Blinking on Tear Volume After Instillation of Midviscosity Artificial Tears

To determine by optical coherence tomography (OCT) the effect of blinking on ocular surface tear volume after instillation of artificial tears. Experimental study. Normal human eyes (n = 21) were imaged to obtain dimensions of the tear film and menisci during blinking. The imaging was carried out immediately and five minutes after the instillation of 35 microl midviscosity artificial tears (1.0% carboxymethylcellulose; Refresh Liquigel; Allergan, Irvine, California, USA). The exposed ocular surface area and the lid lengths were used to calculate the volumes. Immediately after the instillation, total tear volume was increased (P < .001) compared with five minutes after the instillation, with the major increases in the lower tear meniscus volume and tear film volume. After the instillation, blinking caused tear loss in total tear volume because of the decrease of the lower tear meniscus volume (P < .05). In contrast, blinking increased the tear film volume (P < .05). At the end of the eye-opening period, tear film volume decreased and lower tear meniscus volume increased significantly (P < .05), with no significant changes in total tear volume (P > .05). During the blink cycle immediately after the instillation, net loss was evident in tear film volume, lower tear meniscus volume, and total tear volume (P < .05). Blinking plays a crucial role in distribution and removal of instilled tears. When the tear system is overloaded, the increase in blink output helps restore balance.

Dynamic Distribution of Artificial Tears on the Ocular Surface

To study the effects of artificial tear viscosity on tear film thickness, upper and lower tear menisci, and tear volume using optical coherence tomography. The central tear film and tear menisci before and immediately after the instillation of different artificial tears were imaged in 40 eyes of 20 healthy individuals. Carboxymethylcellulose sodium, 1.0% (viscosity, 70 cP), propylene glycol, 0.3%, and polyethylene glycol, 0.4% (10 cP), carboxymethylcellulose, 0.5% (3 cP), and isotonic sodium chloride solution (1 cP) were tested on 2 consecutive days. All measurements, including tear film thickness, the height, radius, and area of the tear meniscus, and the estimated tear volume, were obtained at 0, 5, 20, 40, and 60 minutes after instillation. At instillation, all artificial tears and isotonic sodium chloride solution caused an increase in all tear variables (P < .001). Tear film thickness remained significantly elevated for all drops at 5 minutes (P < .001) and returned to baseline at 20 minutes. Other variables returned to baseline at 5 minutes. Comparing the different drops, tear film thickness and lower meniscus variables at instillation were increased with the more viscous drops (P < .05). Optical coherence tomography demonstrated that all tear preparations, including isotonic sodium chloride solution, increased tear film thickness for at least 5 minutes and other variables immediately after instillation.

Role of the tear film in the optical quality of the human eye

This paper reviews recent studies of the role of the tear film in the optical quality of the eye. Recent investigations focus on the dynamics of the tear film after a blink and its important role in the optical quality of the eye. The results in this review were used in an attempt to understand the optical and visual impact of tear-film breakup in normal eyes and dry eyes. It was noted that patients with dry-eye syndrome have large optical aberrations compared with those in normal eyes, which may be the cause of blurry vision associated with the syndrome. In addition, instillation of artificial tears reduces optical aberrations and thus improves the optical quality of vision in these patients.

Relationships between Central Tear Film Thickness and Tear Menisci of the Upper and Lower Eyelids

To investigate the relationship between central tear film thickness (TFT) and tear menisci of the upper and lower eyelids using real-time optical coherence tomography (OCT). Both eyes of healthy subjects were imaged with a real-time OCT to obtain height, curvature, and area of upper and lower tear menisci simultaneously. Central TFT was indirectly measured by calculating the difference between baseline measurements of the central corneal thickness plus tear film and the true corneal thickness obtained after instillation of artificial tears. Results from two normal blinks were obtained from one eye at each visit and repeated the next day. The average central TFT was 3.4 +/- 2.6 microm. The upper tear meniscus curvature, height, and area were 239 +/- 112 microm, 268 +/- 68 microm, and 22,732 +/- 11,974 microm2 respectively. There were no significant differences in curvatures, heights, or areas between upper and lower tear menisci, nor were there any differences in measured variables between the two blinks at each visit or between the two repeated visits in the right and left eye groups (P > 0.05). The upper and lower tear menisci in each eye group on each day correlated strongly with curvature, height, and area (all P < or = 0.03). However, no tear meniscus variable was a significant predictor of TFT (all P > 0.44). OCT is a promising tool in the measurements of TFT and dimensional variables of tear menisci. Upper and lower tear menisci have nearly identical dimensions.

Repeated Measurements of Dynamic Tear Distribution on the Ocular Surface after Instillation of Artificial Tears

To determine the repeatability of real-time optical coherence tomography (OCT) measurements of tear film thickness (TFT) and variables of tear film menisci. Forty eyes were imaged with a custom-built, real-time OCT to obtain heights, curvatures, and cross-sectional areas of upper and lower tear menisci simultaneously. The central TFT was indirectly determined as the difference between the combined thickness of the central cornea and tear film and the true corneal thickness obtained after instillation of artificial tears. Dynamic tear distribution was determined by OCT imaging immediately and 5, 20, 40, and 60 minutes after tear instillation. Measurements taken after two blinks of one eye at each visit were repeated on the next day. Measurements from the companion eye were made on separate days. There were no significant differences between the two measurements of each variable made on consecutive days. At baseline, upper tear meniscus variables were strongly correlated with the comparable lower meniscus variables. However, there were no significant correlations between TFT and any tear meniscus variable. Immediately after instillation of artificial tears, all measured variables increased significantly. TFT, upper and lower menisci heights, and upper meniscus area remained elevated for at least 5 minutes. In addition there were significant correlations between TFT and the lower tear meniscus height and area. The custom-built OCT showed good repeatability and holds promise in measuring the dynamic distribution of artificial tears on the ocular surface.

Changes in ocular aberrations after instillation of artificial tears in dry-eye patients

Purpose: To study the effect of artificial tear instillation on ocular aberrations in dry-eye patients. Setting: Research, Development and Innovation Department, Instituto Oftalmológico de Alicante, Alicante, Spain. Methods: Ocular aberrations (total, spherical-like, and coma-like) were measured with a Hartmann-Shack aberrometer before and after artificial tear instillation (immediately and 10 minutes later) in 15 eyes of 15 dry-eye patients. Results: Optical aberrations showed a statistically significant reduction after artificial tear instillation ( P<.01). Total aberrations decreased on average by a factor of 2 to 3 times immediately after instillation; the reduction was maintained after 10 minutes ( P>.01). Conclusions: After artificial tear instillation, the reduction in optical aberrations associated with an increasingly irregular tear film may cause an improvement in the optical quality of dry eyes. Wavefront analysis facilitates the evaluation of improvement in optical quality after artificial tear instillation in patients with dry eye.

Effect of artificial tears on corneal surface regularity, contrast sensitivity, and glare disability in dry eyes

Objective To investigate the effects of artificial tears on corneal surface regularity and visual function in dry eyes. Design Nonrandomized, comparative trial. Participants Forty patients (40 eyes) with dry eyes with (group 1, n = 15 eyes) or without (group 2, n = 25 eyes) punctate epithelial keratopathy and a normal control group of 20 individuals (20 eyes) with no ocular abnormalities (group 3). Methods In both dry and normal eyes, the surface regularity index (SRI), surface asymmetry index (SAI), and potential visual acuity (PVA) were measured by computer-assisted videokeratography (TMS-1; Computed Anatomy, New York, NY). Spatial-contrast sensitivity and glare disability were also measured before and 1 minute after instillation of artificial tears. Main outcome measures Differences in SRI, SAI, PVA, spatial-contrast sensitivity, and glare disability between groups, before instillation of tears, and within groups, after instillation of tears. Results Compared with group 3, eyes in group 1 had significantly worse SRI, SAI, PVA, and contrast sensitivity (incomplete glare disability data precluded analysis) before instillation of artificial tears. Differences in corneal surface regularity and visual function between groups 2 and 3 were not significant except for a significantly increased glare disability at low spatial frequency (1.5 cycles per degree [cpd]) in group 2. Significant improvement in SRI, SAI, PVA, and contrast sensitivity were observed after instillation of artificial tears in group 1. In groups 2 and 3, the only significant changes were improvement in glare disability at 1.5 cpd and worsening of the SRI, respectively. Conclusions Tear film changes in dry eye patients may lead to irregularities on the corneal surfaces, causing glare disability. However, these changes may be too subtle in the early stages of dry eyes to be detected by corneal topography or contrast sensitivity measurements. Significant improvement in SRI, SAI, PVA, and contrast sensitivity were found after instillation of artificial tears in dry eyes with punctate epithelial keratopathy.

The Effect of Artificial Tears on Corneal Surface Regularity in Patients with Sjögren Syndrome

Purpose: To evaluate the effect of artificial tears on the topographic parameters associated with corneal surface regularity in patients with Sjögren syndrome. Methods: A total of 38 eyes of 20 patients with Sjögren syndrome were evaluated prospectively. The mean age of the patients was 50.5 ± 15.3 years (range, 28–76). Corneal topography with the Topographic Modeling System (TMS-2, Tomey) was performed before and after the instillation of artificial tears. The surface regularity index (SRI), surface asymmetry index (SAI), potential visual acuity (PVA) and mean astigmatism were compared in dry eyes before and after the instillation of artificial tears. Results: Before the instillation of artificial tears SAI, SRI, PVA and mean antigmatism values were found to be 1.37 ± 1.47, 0.74 ± 0.42, 20/30.92 ± 20/8.12 and 1.53 ± 1.47 D, respectively. In corneal topography performed after the instillation of artificial tears SAI, SRI, PVA and mean astigmatism values were 0.71 ± 0.82, 0.43 ± 0.36, 20/25.92 ± 20/5.55 and 1.08 ± 1.18, respectively. When compared statistically, the SRI, SAI, and mean astigmatism all decreased significantly and the PVA improved (p = 0.0001). Conclusion: Irregular corneal surface in dry eye patients affects optical quality. The statistically significant improvement observed in SRI and SAI values after the instillation of artificial tears also improves the PVA that is especially related to SRI.

Corneal surface regularity and the effect of artificial tears in aqueous tear deficiency

Purpose To evaluate corneal surface regularity and the effect of artificial tears on the regularity of the corneal surface in dry eye. Design A prospective, clinic-based, case-control study. Participants A total of 64 eyes of 33 normal subjects and 42 eyes of 22 patients with aqueous tear deficiency were evaluated. Methods Indices of the TMS-1 corneal topography instrument (Tomey Technology, Cambridge, MA) were used to evaluate corneal surface regularity and potential visual acuity (PVA) in patients with aqueous tear deficiency dry eye before and after the instillation of artificial tears and in normal subjects. The TMS-1 topographic maps were classified into round, oval, symmetric bow-tie, asymmetric bow-tie, and irregular patterns. Main outcome measures The surface regularity index (SRI), surface asymmetry index (SAI), PVA index, and topographic pattern of the TMS-1 were compared between normal and dry eyes and in dry eyes before and after the instillation of artificial tears. Results The SRI and SAI were significantly elevated and the PVA was significantly reduced in dry eye patients compared with normal subjects: 0.31 ± 0.22, 0.30 ± 0.16, and 20/17.89 ± 20/3.04, respectively, in normal subjects and 1.28 ± 0.73, 1.05 ± 1.17, and 20/33.45 ± 20/13.99, respectively, in patients with dry eye ( P < 0.001 for all indices). The average amount of astigmatism was also increased in dry eyes (2.10 ± 1.96 prism diopters) compared with normal eyes (1.13 ± 0.53 prism diopters, P = 0.02). In dry eyes, the SRI and SAI were positively correlated with corneal fluorescein staining scores ( P = 0.005 for SRI and P = 0.016 for SAI). The mean PVA was not significantly different from the mean actual corrected visual acuity. The dry eyes had a significantly lower percentage of symmetric bow-tie patterns and a greater percentage of irregular patterns on topographic maps than normal eyes. After the instillation of artificial tears, the SRI, SAI, and mean astigmatism all decreased significantly ( P < 0.001 for SRI, P < 0.002 for SAI, P = 0.04 for astigmatism) and the PVA improved ( P < 0.001) in dry eyes. An irregular topographic pattern was observed in 45.24% of dry eyes, and this decreased to 30.95% after the instillation of artificial tears ( P < 0.005). Conclusions Patients with aqueous deficiency have an irregular corneal surface that may contribute to their visual difficulties. The SRI and SAI could be used as objective diagnostic indices for dry eye as well as for evaluating the severity of this disease and the effect of artificial tears. Artificial tears have the secondary benefit of smoothing the corneal surface in dry eye.

Topical nonpreserved methylprednisolone therapy for keratoconjunctivitis sicca in Sjögren syndrome

Objective To review the efficacy and side effects of topical nonpreserved corticosteroid therapy for treatment of severe keratoconjunctivitis associated with Sjögren syndrome. Design Retrospective, noncomparative case series. Participants Twenty-one patients with Sjögren syndrome-associated keratoconjunctivitis sicca and annoying ocular irritation. Intervention Treatment with topical nonpreserved methylprednisolone sodium succinate. Main outcome measures Symptom severity, frequency of instillation of artificial tears, corneal fluorescein staining scores, resolution of filamentary keratitis, steroid-related side effects. Results Before starting methylprednisolone therapy, all patients were experiencing moderate-to-severe eye irritation despite prior punctal occlusion in most cases and frequent use of nonpreserved artificial tears by all. After 2 weeks of topical application, three to four times per day, moderate (43%) or complete (57%) relief of irritation symptoms was experienced by all patients and no complications were observed. An average decrease in corneal fluorescein scores of 2.6 ± 0.5 points (on a 12-point scale) was observed, and filamentary keratitis resolved in all ten eyes with this condition. Therapy was stopped after 2 weeks in eight patients, and six of these patients reported that their symptoms remained at a tolerable level for weeks to months. Lower dose steroid therapy was continued in the remaining patients, whose symptoms worsened after attempted weaning. Complications of corticosteroid therapy in patients receiving prolonged therapy included increased intraocular pressure in one patient at 3 months, worsening of pre-existing posterior subcapsular cataracts in one patient at 6 months, and formation of posterior subcapsular cataracts in another patient at 6 months. Conclusions These findings indicate that topical nonpreserved methylprednisolone is an effective treatment option for patients suffering from severe keratoconjunctivitis sicca who continue to experience bothersome eye irritation despite maximum aqueous enhancement therapies. They also suggest that inflammation is a key pathogenic factor in this condition. Careful monitoring is essential in dry eye patients treated with corticosteroids for more than 2 weeks because steroid-related complications (increased intraocular pressure and cataract formation) were observed after several months of therapy in this series. Because of the chronic nature of this disease and the likelihood of patients developing steroid-related complications with their long-term use, topical nonpreserved methylprednisolone therapy appears to be most appropriate for short-term “pulse” treatment of exacerbations of keratoconjunctivitis sicca.