Eric Forister - Academia.edu (original) (raw)

Papers by Eric Forister

Research paper thumbnail of Measuring the benefits of transportation infrastructure investment: Airline scheduling, airport capacity expansion, and consumer welfare

... significantly throughout the day.4 1 Source: ICAO "Economic Contribution of Civil Aviati... more ... significantly throughout the day.4 1 Source: ICAO "Economic Contribution of Civil Aviation: Ripples of ... for the distribution of desired departure times as well as measuring the intensity of ... I allow the attractiveness of the departure time and intensity of nearby competition to explain ...

Research paper thumbnail of Prevalence of Contact Lens-Related Complications: UCLA Contact Lens Study

Eye & Contact Lens-science and Clinical Practice, 2009

Purpose: This study is a cross-sectional analysis of the types and prevalence of contact lens (CL... more Purpose: This study is a cross-sectional analysis of the types and prevalence of contact lens (CL)-related complications among CL wearing patients seen in a university clinic setting. Methods: Data on CL material and design, care system, and ocular complications were recorded and statistically analyzed for CL wearers. Results: Of the 572 patients (846 eyes) recruited during the study, approximately 50% of the eyes had at least one CL-related complication. Rigid gas permeable (GP) CLs had a statistically lower (PϽ0.01) average number of complications (0.54 Ϯ 0.68) than soft contact lenses (SCLs) (0.85 Ϯ 0.82). Papillae and giant papillary conjunctivitis were the most prevalent complications in both GP and SCL wearers. Silicone SCLs (0.79 Ϯ 0.76) had a slightly lower, although not statistically different (Pϭ0.23), rate of complication than nonsilicone SCLs (0.90 Ϯ 0.87). Although not statistically significant (Pϭ0.29), extended wear CL use had a higher complication rate (0.93 Ϯ 0.84) compared with daily wear (0.73 Ϯ 0.79). Use of "other" solution, including generic and private label solutions, had the highest rate of complications for both SCLs (1.11 Ϯ 1.27) and GPs (0.96 Ϯ 0.93) compared with name brand solutions.

Research paper thumbnail of Predicted tear layer oxygen tensions under two designs of silicone hydrogel toric lenses

Contact Lens and Anterior Eye, 2008

The goal of this study was to apply a theoretical analysis of the relationship between contact le... more The goal of this study was to apply a theoretical analysis of the relationship between contact lens oxygen transmissibility and tear layer oxygen tension to silicone hydrogel toric lenses and thereby model the success of such lenses in decreasing corneal hypoxia. Lens thickness was measured at different points along the vertical meridian of one prism-ballasted, one dynamic-stabilized silicone hydrogel toric lens design, and one control "traditional" hydrogel toric lens design. Using lens thickness measurements and the nominal oxygen permeability values of these three lens designs, the subsequent oxygen tension in the tear layer trapped between the contact lens and the anterior cornea (P2) were calculated for both open- and closed-eye conditions using a single corneal chamber model with a personal computer program. We found that cylindrical powers, regardless of lens materials, did not have a statistically significant effect on lens thickness (F=0.30, p=0.5834) to the limitation of our measurements, while contact lens type, spherical power, location on lens, and axis of cylindrical power were all found to do so. When multi-factor ANOVA was applied to the lens thickness and P2 data, contact lens location had a statistically significant effect on P2 values for both prism-ballasted (F=640.16, p<0.0001) and dynamic-stabilized toric lenses (F=352.85, p<0.0001). When the same statistical methodology was used to compare the relative performance of all three lenses on P2 during daily wear, the average P2 values for the three different lens brands were all statistically significantly different, while under closed-eye conditions the average P2 values for both silicone hydrogel toric lenses were no longer statistically significantly different (F=1.00, p=0.3178). Assuming that the critical P2 was 100 mmHg, we predicted that silicone hydrogel toric soft lenses would provide reasonable anterior corneal oxygenation, certainly much enhanced over the environment predicted under traditional hydrogel designs, especially during daily (e.g. open eye) wear. Substantial corneal hypoxia continued to be predicted during extended wear of all lenses, but especially so with the use of traditional hydrogels.

Research paper thumbnail of Compliance with soft contact lens replacement schedules and associated contact lens–related ocular complications: The UCLA Contact Lens Study

Optometry - Journal of The American Optometric Association, 2010

Failure to comply with the manufacturers&... more Failure to comply with the manufacturers' recommended replacement frequency (MRRF) is expected to result in ocular complications. The goal of this study is to evaluate the empirical relationship between compliance with MRRF and the presence of ocular complications. All soft contact lens-wearing patients who presented at either of 2 clinics were evaluated prospectively for contact lens-related complications and for compliance with MRRF. Compliance with MRRF varies significantly across replacement modality (P < 0.01) and lens solution type (P = 0.04). Among noncompliant patients, average days of overwear beyond MRRF significantly varies across age group (P = 0.02), lens material type (P = 0.01), and lens solution type (P = 0.02). Regression analysis controlling for demographic factors and lens and solution type found a marginally significant (P = 0.07) positive effect of days of overwear on average complications per eye. We find noncompliance broadly present across demographic groups and patient types and marginally positively related to complications.

Research paper thumbnail of Measuring the benefits of transportation infrastructure investment: Airline scheduling, airport capacity expansion, and consumer welfare

... significantly throughout the day.4 1 Source: ICAO "Economic Contribution of Civil Aviati... more ... significantly throughout the day.4 1 Source: ICAO "Economic Contribution of Civil Aviation: Ripples of ... for the distribution of desired departure times as well as measuring the intensity of ... I allow the attractiveness of the departure time and intensity of nearby competition to explain ...

Research paper thumbnail of Prevalence of Contact Lens-Related Complications: UCLA Contact Lens Study

Eye & Contact Lens-science and Clinical Practice, 2009

Purpose: This study is a cross-sectional analysis of the types and prevalence of contact lens (CL... more Purpose: This study is a cross-sectional analysis of the types and prevalence of contact lens (CL)-related complications among CL wearing patients seen in a university clinic setting. Methods: Data on CL material and design, care system, and ocular complications were recorded and statistically analyzed for CL wearers. Results: Of the 572 patients (846 eyes) recruited during the study, approximately 50% of the eyes had at least one CL-related complication. Rigid gas permeable (GP) CLs had a statistically lower (PϽ0.01) average number of complications (0.54 Ϯ 0.68) than soft contact lenses (SCLs) (0.85 Ϯ 0.82). Papillae and giant papillary conjunctivitis were the most prevalent complications in both GP and SCL wearers. Silicone SCLs (0.79 Ϯ 0.76) had a slightly lower, although not statistically different (Pϭ0.23), rate of complication than nonsilicone SCLs (0.90 Ϯ 0.87). Although not statistically significant (Pϭ0.29), extended wear CL use had a higher complication rate (0.93 Ϯ 0.84) compared with daily wear (0.73 Ϯ 0.79). Use of "other" solution, including generic and private label solutions, had the highest rate of complications for both SCLs (1.11 Ϯ 1.27) and GPs (0.96 Ϯ 0.93) compared with name brand solutions.

Research paper thumbnail of Predicted tear layer oxygen tensions under two designs of silicone hydrogel toric lenses

Contact Lens and Anterior Eye, 2008

The goal of this study was to apply a theoretical analysis of the relationship between contact le... more The goal of this study was to apply a theoretical analysis of the relationship between contact lens oxygen transmissibility and tear layer oxygen tension to silicone hydrogel toric lenses and thereby model the success of such lenses in decreasing corneal hypoxia. Lens thickness was measured at different points along the vertical meridian of one prism-ballasted, one dynamic-stabilized silicone hydrogel toric lens design, and one control "traditional" hydrogel toric lens design. Using lens thickness measurements and the nominal oxygen permeability values of these three lens designs, the subsequent oxygen tension in the tear layer trapped between the contact lens and the anterior cornea (P2) were calculated for both open- and closed-eye conditions using a single corneal chamber model with a personal computer program. We found that cylindrical powers, regardless of lens materials, did not have a statistically significant effect on lens thickness (F=0.30, p=0.5834) to the limitation of our measurements, while contact lens type, spherical power, location on lens, and axis of cylindrical power were all found to do so. When multi-factor ANOVA was applied to the lens thickness and P2 data, contact lens location had a statistically significant effect on P2 values for both prism-ballasted (F=640.16, p<0.0001) and dynamic-stabilized toric lenses (F=352.85, p<0.0001). When the same statistical methodology was used to compare the relative performance of all three lenses on P2 during daily wear, the average P2 values for the three different lens brands were all statistically significantly different, while under closed-eye conditions the average P2 values for both silicone hydrogel toric lenses were no longer statistically significantly different (F=1.00, p=0.3178). Assuming that the critical P2 was 100 mmHg, we predicted that silicone hydrogel toric soft lenses would provide reasonable anterior corneal oxygenation, certainly much enhanced over the environment predicted under traditional hydrogel designs, especially during daily (e.g. open eye) wear. Substantial corneal hypoxia continued to be predicted during extended wear of all lenses, but especially so with the use of traditional hydrogels.

Research paper thumbnail of Compliance with soft contact lens replacement schedules and associated contact lens–related ocular complications: The UCLA Contact Lens Study

Optometry - Journal of The American Optometric Association, 2010

Failure to comply with the manufacturers&... more Failure to comply with the manufacturers' recommended replacement frequency (MRRF) is expected to result in ocular complications. The goal of this study is to evaluate the empirical relationship between compliance with MRRF and the presence of ocular complications. All soft contact lens-wearing patients who presented at either of 2 clinics were evaluated prospectively for contact lens-related complications and for compliance with MRRF. Compliance with MRRF varies significantly across replacement modality (P < 0.01) and lens solution type (P = 0.04). Among noncompliant patients, average days of overwear beyond MRRF significantly varies across age group (P = 0.02), lens material type (P = 0.01), and lens solution type (P = 0.02). Regression analysis controlling for demographic factors and lens and solution type found a marginally significant (P = 0.07) positive effect of days of overwear on average complications per eye. We find noncompliance broadly present across demographic groups and patient types and marginally positively related to complications.