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Publications (16)26.65 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The effective management of dry eye must include a clinically meaningful reduction in ocular staining. Evaluations of corneal and conjunctival staining and other ocular symptoms of dry eye were conducted for a new formulation of polyethylene glycol 400/propylene glycol-based lubricant eye drops containing hydroxypropyl guar as a gelling agent (Test Product) in comparison to Optive Lubricant Eye Drops (Control Product) in adult patients with dry eye. One hundred thirteen patients, 18 years of age and older, with dry eye were enrolled in a prospective, double-masked, multisite, parallel-group study. After a 2-week run-in period during which patients administered aqueous saline eye drops 4 times daily (QID) in each eye, patients were randomized (1:1) to receive either Test Product or Control Product to be administered QID for 6 weeks. Efficacy and safety were evaluated by corneal and conjunctival staining scores, tear film breakup time, assessments of ocular symptoms, ocular surface disease index (OSDI) scores, dry eye treatment satisfaction, visual function-14 questionnaires, and adverse events. The intent-to-treat data set included 105 patients randomized to Test Product (n = 52) or Control Product (n = 53). Patients primarily were between the ages of 18-64 years (70.5%), female (73.3%), white (93.3%), and not Hispanic (81.9%). Patients in the Test Product group exhibited significantly lower mean corneal staining scores than the Control Product group at day 14 (P = 0.0009) and day 42 (P = 0.0106), and significantly lower mean conjunctival staining scores at day 28 (P = 0.0475) and day 42 (P = 0.0009). Patients in both treatment groups reported significant reductions in the mean scores for the ocular symptoms of dryness, gritty/sandy feeling, and burning (P <or= 0.0021 for all comparisons to baseline). Lastly, a significantly lower OSDI score than baseline was reported at day 42 by patients in both the Test Product (P = 0.0013) and Control Product (P < 0.0001) groups. The results of this study indicate that the Test Product significantly reduced corneal and conjunctival staining, indicating a reduction in disease severity. Evaluations of ocular staining scores provide clinically meaningful evidence of dry eye severity and are an important indicator of dry eye disease progression.
    Journal of ocular pharmacology and therapeutics: the official journal of the Association for Ocular Pharmacology and Therapeutics 08/2010; 26(4):347-53. · 1.46 Impact Factor
  • Mike T Christensen, Anna E Martin, Marc Bloomenstein
    Optometry (St. Louis, Mo.) 06/2009; 80(6):315.
  • Justin R Webb, Jerry R Paugh, Mike T Christensen
    Optometry (St. Louis, Mo.) 06/2009; 80(6):303.
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    ABSTRACT: The purpose of this investigation was to measure the precorneal residence time of saline and five marketed artificial tears in dry eye subjects using fluorometry. FITC-dextran, 70 kDa molecular weight, was admixed under sterile conditions (0.1% wt/vol) into buffered saline and the marketed artificial tear formulations of varying viscosity. Precorneal residence time (RT) was measured directly in 16 mild to moderate dry eye subjects, classified by sub-type, in a six-way cross-over, masked and randomized study. FITC-dextran tracer decay with a scanning fluorometer was used to estimate the gross RT (i.e., the time in minutes for the signal to return to baseline). All subjects were classified as having non-inflammatory meibomian gland dysfunction except one, who had a mixture of aqueous deficiency and meibomian gland dysfunction. In two separate determinations, the saline RTs were 19.1 +/- 7.4 and 17.6 +/- 8.2 min. The RTs for the formulations varied to some degree by viscosity, with two higher viscosity formulations demonstrating the longest RTs of 36 to 41 min, approximately twice that of saline (p < 0.001 for both 0.4% polyethylene glycol/0.3% propylene glycol, and 1.0% carboxymethylcellulose). An oil emulsion, low viscosity carboxymethylcellulose and moderate viscosity hydroxypropylmethylcellulose-containing formulation were not statistically different from saline (RTs of 18, 22 and 24 min, p values = 0.983, 0.818 and 0.099, respectively). More than two-fold RT differences were found for the higher viscosity, more muco-adhesive formulations compared to saline. However, other formulations provided RTs close to saline, suggesting that RT is influenced by factors other than simple viscosity. Future studies should examine the interplay of spreading characteristics, pseudoplasticity and muco-adhesion relative to RT to determine the individual and cumulative effects on formulation retention.
    Optometry and Vision Science 08/2008; 85(8):725-31. · 2.04 Impact Factor
  • Mike T. Christensen, Anna E. Martin, Robin E. David
    Optometry - Journal of the American Optometric Association 06/2008; 79(6):333–334. · 1.34 Impact Factor
  • Mike Christensen, Marion Tudor, David Meadows, Ralph Stone
    Optometry - Journal of the American Optometric Association 06/2006; 77(6):294–295. · 1.34 Impact Factor
  • Ken N Sall, Stephen M Cohen, Mike T Christensen, Jerry M Stein
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    ABSTRACT: To evaluate the efficacy of marketed artificial tears in relieving the signs and symptoms of dry eye when used as supportive therapy to a cyclosporine-based ophthalmic emulsion. Sixty-one patients were enrolled in this randomized, investigator-masked, parallel study of 6 months' duration. Eligible patients needed a Schirmer I score without anesthesia of 7 mm or less at day -7 and to answer that they needed artificial tears at least "some of the time." Corneal staining of 3 or more (National Eye Institute grid, 15 points) at day -7 and day 0 in the same eye was also required. Patients were randomized to one of three regimens: Restasis (0.05% cyclosporine) twice per day with Systane used a minimum of once per day (Restasis + Systane); Restasis twice per day with Refresh Tears used a minimum of once per day (Restasis + Refresh); and Systane alone used four times per day. Signs and symptoms were measured at days -7, 0, 7, 14, 28, 42, 120, and 180. A statistical difference was seen in favor of Restasis + Systane versus Restasis + Refresh for corneal staining (P = 0.0048) change from baseline and a trend (P = 0.0725) for increased tear film breakup time at 6 months. There were no differences between treatment groups for Schirmer score, conjunctival staining, or conjunctival injection. Significant differences were seen in favor of Restasis + Systane versus Restasis + Refresh for less ocular burning (P = 0.0210), stinging (P = 0.0314), grittiness (P = 0.0128), and dryness (P = 0.0132). Systane was better than Restasis + Refresh for less burning (P = 0.0288), dryness (P = 0.0480), and scratchiness (P = 0.0294). Results indicate that the choice of concomitant therapy used with Restasis has significant effects on outcome measures. Both supportive therapies were compatible with Restasis.
    Eye & Contact Lens Science & Clinical Practice 02/2006; 32(1):21-6. · 1.68 Impact Factor
  • Optometry - Journal of the American Optometric Association 06/2005; 76(6):392–393. · 1.34 Impact Factor
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    ABSTRACT: To identify and characterize moderate dry eye in non-contact lens wearers with a new scoring system-based dry eye questionnaire and to determine which objective tests better differentiate patients with moderate dry eye from healthy patients. Fifty-two healthy subjects (21 women and 31 men with a mean age of 27.8 +/- 9.2 years) and 37 subjects with moderate dry eye (33 women and 4 men with a mean age of 36.4 +/- 12.9 years) completed a 42-item dry eye questionnaire. Seventeen healthy subjects (11 women and 6 men with a mean age of 30.5 +/- 9.7 years) and 28 subjects with moderate dry eye (24 women and 4 men with a mean age of 38.50 +/- 3.8 years) underwent additional objective assessment of ocular surface health, tear osmolality, tear stability, and tear volume. Subjects with moderate dry eye scored significantly higher (49.8 +/- 20.3, P<0.0001) on the dry eye questionnaire than did normal subjects (11.7 +/- 10.3). Ocular irritation symptoms worsened with progression of time of day in both groups of subjects. Internal reliability (0.95 Cronbach alpha) was excellent, and concurrent validity (Spearman rho 0.507) was acceptable when compared to the McMonnies and Ho dry eye questionnaire. Significant differences in tear osmolality (P<0.00001), invasive tear breakup time (P<0.034), and corneal vital dye staining (P<0.0001) were detected between the two groups of subjects. A stepwise linear regression on objective clinical tests, however, did not account for 77% of the total variance in the questionnaire scores. A unique scoring system-based dry eye questionnaire was validated to separate non-contact lens wearers with moderate dry eye from healthy subjects. Objective tests of tear osmolality and stability and ocular surface integrity were better than other clinical measures at identifying differences between the two subject groups. The results strongly support the evidence that the diagnosis and treatment of moderate dry eye requires a detailed assessment of self-perceived symptoms and that objective clinical testing alone may be insufficient.
    Eye & Contact Lens Science & Clinical Practice 06/2005; 31(3):96-104. · 1.68 Impact Factor
  • Optometry - Journal of the American Optometric Association 06/2005; 76(6):392. · 1.34 Impact Factor
  • The ocular surface 01/2005; 3:S102. · 4.21 Impact Factor
  • Optometry - Journal of the American Optometric Association 06/2004; 75(6):372–373. · 1.34 Impact Factor
  • Optometry - Journal of the American Optometric Association 06/2004; 75(6):357–358. · 1.34 Impact Factor
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    ABSTRACT: To evaluate the efficacy of a new lubricant eye drop containing polyethylene glycol 400 and propylene glycol demulcents with hydroxypropyl-guar as a gelling agent (Test Product) to a system with carboxymethylcellulose (Control Product) for reducing dry eye signs and symptoms. Eighty-seven dry eye volunteers were enrolled at seven sites for this six-week, concurrently controlled, double-masked clinical study. The Test Product significantly reduced conjunctival staining (p = 0.025) and temporal corneal staining (p = 0.024) compared to the Control. The Test Product also significantly reduced symptoms of dryness in the morning and evening, compared to the Control (p = 0.015 and p = 0.023, respectively). Subjects in the Test treatment group reported lower frequencies of foreign body sensation and felt their eyes were "refreshed longer" compared to those in the Control group (p = 0.033 and p = 0.037, respectively). The Test Product was more effective at reducing both the signs and symptoms of dry eye compared to the carboxymethylcellulose containing Control.
    Current Eye Research 02/2004; 28(1):55-62. · 1.66 Impact Factor
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    ABSTRACT: Purpose. To evaluate the effectiveness of marketed artificial tears in relieving dry eye signs/symptoms when used as supportive therapy to a cyclosporine based ophthalmic emulsion. Methods. 61 patients were enrolled in this randomized, investigator masked, parallel study of 6-months duration. Enrollment criteria included corneal staining of ≥ 3 (NEI grid), Schirmer w/o anesthesia of ≤ 7mm and subjects had to answer that they needed artificial tears at least "some of the time". Subjects were randomized to one of 3 treatment groups. Treatment (Tx)1: Restasis® (0.05% cyclosporine) BID w/Systane® (PEG 400/propylene glycol w/HP-Guar) used a minimum of 1/day as supportive therapy. Tx2: Restasis® BID w/Refresh Tears® (carboxymethylcellulose) used a minimum of 1/day as supportive therapy. Tx3: Systane alone QID. Signs and symptoms were measured at Days -7, 0, 7, 14, 28, 42, 120 and 180. Results. A statistical difference was seen in favor of Tx1 (Restasis+Systane) vs Tx2 (Restasis+Refresh Tears) for corneal staining (p=0.0048) and a trend (p=0.0725) for increased TFBUT at 6 months. Schirmer showed a non-significant increase from baseline Tx1=1.41, Tx2=2.15, Tx3=1.42 mm. Significant differences were seen in favor Tx1 vs Tx2 for less Ocular Burning (p=0.0210), Stinging (p=0.0314), Grittiness (p=0.0128) and Dryness (p=0.0132). Tx3 was better than Tx2 for less Burning (p=0.0288), Dryness (p=0.0480) and Scratchiness (p=0.0294). Both supportive therapies were compatible with Restasis. Conclusion. The choice of artificial tears used as supportive therapy with Restasis is important. There were significant clinical advantages with Restasis+Systane vs Restasis+Refresh Tears. While there were no clinical differences noted for Restasis+Systane vs Systane, Systane should be studied with more patients as a first line therapy. This study Last observation carried forward was used to impute data for missed visits and discontinued patients in the intent-to-treat dataset. Baseline differences between treatment groups were evaluated with two-sided, two-sample t-tests or Chi-Square/Fisher tests as applicable. Efficacy variables were evaluated with a repeated measures analysis of variance. Least squares means comparisons were used to investigate treatment differences at each day. The type 1 error rate was set to 0.05, and 0.05
    The ocular surface 01/2004; 3. · 4.21 Impact Factor
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    ABSTRACT: To determine lysozyme deposition as a function of time in soft, high-water content, ionic (group IV) contact lenses. ACUVUE lenses were worn on an extended-wear basis (15 minutes, 2 hours, 4 hours, 6 hours, 8 hours, 1 day, 2 day, and so forth, up to 11 consecutive days). New lenses were dispensed at the beginning of each lens-wear period. After each wear cycle, lenses were analyzed for lysozyme deposition by high performance liquid chromatography. Lysozyme rapidly accumulated on lenses (15 minutes approximately 55 microg/lens) and reached a plateau level by day 6 ( approximately 1300 microg/lens). Most patients in the study showed a plateau range between 1200 and 1400 microg/lens. Six-month and 12-month follow-up studies with ACUVUE lenses showed minimal variation at the 5-day wear time point between the initial, sixth, and 12th month results. This study measured the rate of lysozyme buildup on lenses over time and demonstrated that lysozyme levels associated with group IV lenses reached a plateau after approximately 1 week of extended wear. Little variability was seen in lens lysozyme deposition up to 1 year later. The information derived from this study concerning the rate and variability of deposition has implications for the design and interpretation of cleaning studies and contact lens performance evaluations.
    Eye & Contact Lens Science & Clinical Practice 05/2003; 29(2):79-82. · 1.68 Impact Factor