The ocular pulse amplitude at different intraocular pressure: a prospective study

To investigate changes in ocular pulse amplitude (OPA) during a short-term increase in intraocular pressure (IOP) and to assess possible influences of biometrical properties of the eye, including central corneal thickness (CCT) and axial length.

Intraocular pressure changes following 20G pars-plana vitrectomy

To observe the excursions of short-term intraocular pressure (IOP) after 20-G pars-plana vitrectomy (ppV).

INVESTIGATION OF INTRAOCULAR PRESSURE AS A PREDICTOR OF TRAUMATIC EYE INJURIES

Eye injuries are a large societal problem in both the military and civilian sectors. Eye injury rates are increasing in recent military conflicts, and there are over 1.9 million eye injuries in the United States civilian sector annually. In order to develop a better understanding of eye injury risk, several previous studies have developed eye injury criteria based on projectile characteristics. While these injury criteria have been used to estimate eye injury potential of impact scenarios, they require that the mass, size and velocity of the projectile are known. It is desirable to develop a method to assess the severity of an eye impact in environments where it would be difficult or impossible to determine these projectile characteristics. The current study presents a measurement technique for monitoring intraocular pressure of the eye under impactloading. Through experimental tests with a custom pressure chamber, a subminiature pressure transducer was validated to be thermally stable and suitable for testing in an impact environment.Once validated, the transducer was utilized intraocularly, inserted through the optic nerve, to measure the pressure of the eye during blunt-projectile impacts. A total of 150 impact tests were performed using projectiles ranging from 3.2 mm to 17.5 mm in diameter. Investigation of the relationship between projectile energy and intraocular pressure lead to the identification of at least two distinct trends. Intraocular pressure and normalized energy measurements indicated a different response for penetrating-type globe rupture injuries with smaller diameter (d < 1 cm)projectiles, and blunt-type globe rupture injuries with larger diameter (d > 1 cm) projectiles. Furthermore, regression analysis indicates that relationships exist between intraocular pressureand projectile energy that may allow quantification of eye injury risk based on pressure data, and also that intraocular pressure measurements of impact may lead to a better understanding of thetransition between penetrating and blunt globe rupture injury mechanisms.

Statistical modeling of the eye for multimodal treatment planning for external beam radiation therapy of intraocular tumors

Ocular anatomy and radiation-associated toxicities provide unique challenges for external beam radiation therapy. For treatment planning, precise modeling of organs at risk and tumor volume are crucial. Development of a precise eye model and automatic adaptation of this model to patients' anatomy remain problematic because of organ shape variability. This work introduces the application of a 3-dimensional (3D) statistical shape model as a novel method for precise eye modeling for external beam radiation therapy of intraocular tumors.

The Modernity of la Mode: a History of the French Revolution Through the Lens of Fashion, Culture, and Identity

In my thesis, I explore the cultural history of the French Revolution and its relation to the modern era which ensued. Many historians have studied the French Revolution as it relates to culture, the rise of modernity, and fashion. I combine the unique histories of all three of these aspects to reach an understanding of the history of the French Revolution and fashion’s role in bringing about change. In the majority of literature of costume history, discussion of fashion surrounds its reflective properties. Many historians conclude fashion as a reflection of the broader cultural shifts that occurred during the Revolution. I, on the other hand, propose that fashion is an active force in bringing out cultural change during this time. In exploring fashion as a historical motivator, I examine the aesthetic world of fashion from 1740 to 1815, the modern system of cultural dissemination of fashion through particular historical heroes, and the rise of “taste” and its relation to modern identity. Through aesthetics, culture, and identity, I argue that fashion is a decisive force of culture in that it creates a visual world through which ideas form and communicate.

Self-Immolation In Tibet: Beyond The Lens Of The Western Media

This thesis provides a critique of Western media articles concerning self-immolation in Tibet. I begin by illustrating how the Western media provides reductionist accounts of Tibetan self-immolation by depicting the act solely as a form of political protest in response to Chinese occupation. I argue that these limited portrayals of self-immolation can be attributed to the Shangri-La imagery that characterizes much of the Western conceptions of Tibet. Through Shangri-La imagery, both Tibetans and their Buddhist religion are portrayed as utopic, peaceful, and able to provide the antidote to solving Western problems relating to modernization and consumerism. After illustrating the ways in which Shangri-La imagery influences Western media portrayals of Tibetan self-immolation, this thesis explores the commonly disregarded Buddhist dimensions of the act. Looking to Buddhist doctrine, scripture, and history, this thesis establishes a clear relationship between self-immolation and Buddhism, which situates the act as being more complicated than mere political protest. I argue that these limited portrayals given by the Western media are problematic because they overlook a fundamental aspect of self-immolation, thus potentially misrepresenting Tibetans. This thesis explores the Buddhist dimensions of self-immolation as a possible way to further understand what has led more than one hundred Tibetans to perform this act during the time of political crisis.

Long-term intraocular pressure changes in patients with neovascular age-related macular degeneration treated with ranibizumab

BACKGROUND/AIMS To investigate the long-term effects of multiple intravitreal injections (IVTs) of ranibizumab (Lucentis) on intraocular pressure (IOP) in patients with neovascular age-related macular degeneration. METHODS In 320 eyes, IOP measurements were performed at baseline prior to injection and compared with IOP measurements of the last visit. Correlations between mean IOP change and total number of IVTs, visual acuity or patient age were tested. RESULTS The mean IOP increase was 0.8 ± 3.1 mm Hg (p < 0.0001). Seven eyes showed final IOP values between 22 and 25 mm Hg. The mean follow-up was 22.7 ± 14.1 months. No further correlations between IOP change and number of IVTs, visual acuity or patient age have been found. CONCLUSIONS This study demonstrated a statistically significant IOP increase in patients treated with repeated injections of ranibizumab. However, IOP increase required no glaucoma treatment during the study. Therefore, repeated injections with ranibizumab can be considered safe with regard to long-term IOP changes in patients without ocular hypertension or glaucoma.

Effect of oral donepezil on intraocular pressure in normotensive Alzheimer patients

Donepezil, a selective acetylcholinesterase (AChE) inhibitor, has been shown to reduce intraocular pressure (IOP) in ocular normotensive rabbit eyes. The aim of this investigation was to evaluate the effect of oral donepezil on IOP and pupil diameter after mid-term oral treatment in normotensive persons. Thirty-two newly diagnosed Alzheimer patients with normal IOP and no further antiglaucomatous treatment were included in the study. IOP and pupil diameter were evaluated before and 4 weeks after daily intake of 5 mg donepezil. IOP and pupil diameter were significantly lower/smaller after 4 weeks of treatment. The mean IOP of all 63 eyes was 14.1 mmHg before and 12.8 mmHg after treatment (8.8% reduction). Mean pupil diameter constricted from 3.9 to 3.6 mm (-7.4%). These findings show that donepezil, and, possibly, other selective AChE inhibitors, can potentially be used to treat glaucoma. They are also known to have neuroprotective effects in Alzheimer's, and, therefore, might have an additional therapeutic benefit.

Noninvasive determination of intraocular pressure (IOP) in nonsedated mice of 5 different inbred strains

BACKGROUND: Noninvasive intraocular pressure (IOP) measurement in mice is critically important for understanding the pathophysiology of glaucoma. Rebound tonometry is one of the methods that can be used for obtaining such measurements. We evaluated the ability of the rebound tonometer (RT) to determine IOP differences among various mouse strains and whether differences in corneal thickness may affect IOP measurements in these animals. MATERIALS AND METHODS: Five different commonly used mouse strains (BALB/C, CBA/CAHN, AKR/J, CBA/J, and 129P3/J) were used. IOP was measured in eyes from 12 nonsedated animals (6 male and 6 female) from each strain at 2 to 3 months of age using the RT. IOPs were measured in all animals, on 2 different days between 10 AM and 12 PM. Subsequently, a number of eyes from each strain were cannulated to provide a calibration curve specific for that strain. Tonometer readings for all strains were converted to apparent IOP values using the calibration data obtained from the calibration curve of the respective strain. For comparison purposes, IOP values were also obtained using the C57BL/6 calibration data previously reported. IOP for the 5 strains, male and female animals, and the different occasion of measurement were compared using repeat measures analysis of variance. The central corneal thickness (CCT) of another group of 8 male animals from each of the 5 strains was also measured using an optical low coherence reflectometry (OLCR) pachymeter modified for use with mice. CCT values were correlated to mean IOPs of male animals and to the slopes and intercept of individual strain calibration curves. RESULTS: Noninvasive IOP measurements confirm that the BALB/C strain has lower and the CBA/CAHN has higher relative IOPs than other mouse strains while the AKR/J, the CBA/J, and the 129P3/J strains have intermediate IOPs. There is a very good correlation of apparent IOP values obtained by RT with previously reported true IOPs obtained by cannulation. There was a small but statistically significant difference in IOP between male and female animals in 2 strains (129P3/J and AKR/J) with female mice having higher relative IOPs. No correlation between CCT and IOP was detected. CCT did not correlate with any of the constants describing the calibration curves in the various strains. CONCLUSIONS: Noninvasive IOP measurement in mice using the RT can be used to help elucidate IOP phenotype, after prior calibration of the tonometer. CCT has no effect on mouse IOP measurements using the RT.

Comparison of the effects of bimatoprost and a fixed combination of latanoprost and timolol on circadian intraocular pressure

OBJECTIVE: To compare the effect of bimatoprost and the fixed combination of latanoprost and timolol (LTFC) on 24-hour mean intraocular pressure (IOP) after patients are switched from a nonfixed combination of latanoprost and timolol. DESIGN: Randomized, double-masked, multicenter clinical trial. PARTICIPANTS: Two hundred patients with glaucoma or ocular hypertension. METHODS: Included were patients who were controlled (IOP < 21 mmHg) on the nonfixed combination of latanoprost and timolol for at least 3 months before the baseline visit or patients on monotherapy with either latanoprost or timolol who were eligible for dual therapy not being fully controlled on monotherapy. The latter group of patients underwent a 6-week wash-in phase with the nonfixed combination of latanoprost and timolol before baseline IOP determination and study inclusion. Supine and sitting position IOPs were recorded at 8 pm, midnight, 5 am, 8 am, noon, and 4 pm at baseline, week 6, and week 12 visits. MAIN OUTCOME MEASURE: An analysis of covariance model was used for a noninferiority test of the primary efficacy variable, with mean area under the 24-hour IOP curve after 12 weeks of treatment as response variable and treatment, center, and baseline IOP as factors. A secondary analysis was performed on the within-treatment change from baseline. RESULTS: Mean baseline IOPs were 16.3+/-3.3 mmHg and 15.5+/-2.9.mmHg in the bimatoprost and LTFC groups, respectively. At week 12, mean IOPs were 16.1+/-2.5 mmHg for the bimatoprost group and 16.3+/-3.7 mmHg for the LTFC group, and no significant difference between the 2 treatment groups could be found. As compared with baseline, mean IOP increased by 0.3+/-3.6 mmHg during the day and decreased by 0.8+/-3.8 mmHg during the night in the bimatoprost group, whereas there were increases of 1.43+/-2.6 mmHg and 0.14+/-3.2 mmHg in the LTFC group, respectively. CONCLUSIONS: Bimatoprost is not inferior to the LTFC in maintaining IOP at a controlled level during a 24-hour period in patients switched from the nonfixed combination of latanoprost and timolol.