We want to thank all the participants for their help and support in filling out the survey and sending the images of their eyes. The ERC Center grant provided funding for the IRB.

The present study was conducted following the declaration of Helsinki, and the protocol was approved by the Institutional Review Board at Solutions (IRB, 2021/09/14). The study followed the reporting guidelines of the Declaration of Helsinki. All the participants provided informed consent for the questionnaire. The survey was conducted entirely online via the Internet. If the participants met the eligibility requirements, the consent forms, research project flier, and OSDI questionnaire were emailed to them. After submitting the consent forms and completing the OSDI questionnaire, a $10 gift credit card was issued online for completing the survey.
1. OSDI survey for DES evaluation
<ol>
	<li>Use the following criteria: low OSDI score (0-20 points); moderate OSDI score (21-45 points); high OSDI score (46-100points). 
	NOTE: The diagnostic criteria for DES by OSDI score is &#8805;13.</li>
	<li>Ask the eligible subjects to fill out the survey online (Table 1).</li>
</ol>
2. Determination of limbal redness via AOS software
<ol>
	<li>Take a picture of the eyes, one eye at a time. 
	NOTE: The picture has to be clear for the analysis.</li>
	<li>Assign the subject an ID number. Save the subject ID.</li>
	<li>To add a subject, click on the Add tab. 
	NOTE: The system automatically generates the patient ID.</li>
	<li>Fill in the Title tab. Fill in the First name and the surname.</li>
	<li>Fill in the date of birth.</li>
	<li>Fill in the email address, and then confirm the email address.</li>
	<li>Fill in the National Health Service ID (NHS ID) and the Medical Record Number (MRN) number.</li>
	<li>Fill in the Note tab. Then, click on Save.</li>
	<li>Now, select the Subject ID. Then, add/view images. Then, click on + Add.</li>
	<li>Upload the images to the AOS software (see Table of Materials) to evaluate the limbal redness. Upload the right eye first, then the left eye.</li>
	<li>Click on the New Exam tab. Then, click on the Image + tab.</li>
	<li>Add the right eye, and then click on the Selected Media tab.</li>
	<li>Click on the Bulbar icon. Then, click on the Area tab. Click on Analysis Bulbar Redness Grading Scale 0-4.</li>
	<li>Click on the image to start at the limbal area close to the pupil border and follow a pattern to cover the limbal area (Figure 1). Then, click on Save Analysis. 
	NOTE: The redness grade and the % of vessels are saved.</li>
	<li>Click on the Redness Map and Save Analysis.</li>
	<li>Click on Generate Report. Click on both images to generate PDF. 
	NOTE: The PDF report includes the patient&#39;s first name, surname, date of birth, Patient ID, NHS number, and by whom the patient was examined. The PDF report also includes the examination date and examination type.</li>
	<li>Repeat Steps 2.9-2.22; then, add the left-eye image.</li>
	<li>Grade the limbal redness using the AOS software. Analyze the images for bulbar conjunctival redness with a validated objective grading software using the &#34;bulbar redness&#34; function in the limbal areas of the conjunctiva, using an automatic continuous grading from 0-4 in 0.1 unit. 
	NOTE: Grade 0 is minimum redness; Grade 4 is severe redness (Figure 1). Grades 0-1 are coded grade I, Grades 1-2 are coded grade II, Grades 2-3 are coded grade III, and Grades 3-4 are coded grade IV to match the OSDI survey grading system.</li>
</ol>
3. Statistical analysis
<ol>
	<li>Collect the data and analyze the data using Microsoft Excel.
	<ol>
		<li>Summarize the Subject ID, age, gender, race, OSDI score, and the limbal redness in one table.</li>
		<li>Calculate the age, OSDI score, and the limbal redness score mean using Excel software.</li>
	</ol>
	</li>
	<li>Determine the mean &#177; standard deviation of the age, OSDI score, and limbal redness score.</li>
	<li>Calculate the prevalence rate in percentage.
	<ol>
		<li>Divide the number of subjects by the total number of subjects (40), and then multiply by 100.
		<ol>
			<li>Divide the number of subjects with low DES (LDES) by the total number of subjects (40), and then multiply by 100.</li>
			<li>Divide the number of subjects with moderate DES (MODDES) by the total number of subjects (40), and then multiply by 100.</li>
			<li>Divide the number of subjects with severe DES (SDES) by the total number of subjects (40), and then multiply by 100.</li>
		</ol>
		</li>
		<li>Perform the linear regression analysis using Excel software to determine the mean of the two values (x-axis) and the difference between the two means (y-axis). Also, determine the p-value. 
		NOTE: The linear regression analysis determines the relationships between the OSDI score and the AOS redness score.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Meduri, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ocular+surface+manifestation+of+COVID-19+and+tear+film+analysis.">Ocular surface manifestation of COVID-19 and tear film analysis.</a> Scientific Reports. 10 (1), 20178 (2020).</li><li>dell'Omo, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+COVID-19-related+lockdown+on+ophthalmic+practice+in+Italy:+A+report+from+39+institutional+centers.">Effect of COVID-19-related lockdown on ophthalmic practice in Italy: A report from 39 institutional centers.</a> European Journal of Ophthalmology. 32 (1), 695-703 (2022).</li><li>Ganne, P., Najeeb, S., Chaitanya, G., Sharma, A., Krishnappa, N. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+eye+strain+epidemic+amid+COVID-19+pandemic+-+A+cross-sectional+survey.">Digital eye strain epidemic amid COVID-19 pandemic - A cross-sectional survey.</a> Ophthalmic Epidemiology. 28 (4), 285-292 (2021).</li><li>Al-Namaeh, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coronavirus+disease+pandemic+and+dry+eye+disease:+A+methodology+concern+on+the+causal+relationship.">Coronavirus disease pandemic and dry eye disease: A methodology concern on the causal relationship.</a> Medical Hypothesis Discovery and Innovation in Ophthalmology. 11 (1), 42-43 (2022).</li><li>Hayirci, E., Yagci, A., Palamar, M., Basoglu, O. K., Veral, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+continuous+positive+airway+pressure+treatment+for+obstructive+sleep+apnea+syndrome+on+the+ocular+surface.">The effect of continuous positive airway pressure treatment for obstructive sleep apnea syndrome on the ocular surface.</a> Cornea. 31 (6), 604-608 (2012).</li><li>Giannaccare, G., Vaccaro, S., Mancini, A., Scorcia, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dry+eye+in+the+COVID-19+era:+how+the+measures+for+controlling+pandemic+might+harm+ocular+surface.">Dry eye in the COVID-19 era: how the measures for controlling pandemic might harm ocular surface.</a> Graefe's Archive for Clinical and Experimental Ophthalmology. 258 (11), 2567-2568 (2020).</li><li>Uchino, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prevalence+of+dry+eye+disease+and+its+risk+factors+in+visual+display+terminal+users:+the+Osaka+study.">Prevalence of dry eye disease and its risk factors in visual display terminal users: the Osaka study.</a> American Journal of Ophthalmology. 156 (4), 759-766 (2013).</li><li>Inomata, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+and+risk+factors+associated+with+diagnosed+and+undiagnosed+symptomatic+dry+eye+using+a+smartphone+application.">Characteristics and risk factors associated with diagnosed and undiagnosed symptomatic dry eye using a smartphone application.</a> JAMA Ophthalmology. 138 (1), 58-68 (2020).</li><li>Schiffman, R. M., Christianson, M. D., Jacobsen, G., Hirsch, J. D., Reis, B. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliability+and+validity+of+the+Ocular+Surface+Disease+Index.">Reliability and validity of the Ocular Surface Disease Index.</a> Archives of Ophthalmology. 118 (5), 615-621 (2000).</li><li>Finis, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+OSDI+and+SPEED+questionnaires+for+the+evaluation+of+dry+eye+disease+in+clinical+routine.">Comparison of the OSDI and SPEED questionnaires for the evaluation of dry eye disease in clinical routine.</a> Der Ophthalmologe. 111 (11), 1050-1056 (2014).</li><li>Huntjens, B., Basi, M., Nagra, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluating+a+new+objective+grading+software+for+conjunctival+hyperaemia.">Evaluating a new objective grading software for conjunctival hyperaemia.</a> Contact Lens &amp; Anterior Eye. 43 (2), 137-143 (2020).</li><li>Hwang, H. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Easy+and+effective+test+to+evaluate+tear-film+stability+for+self-diagnosis+of+dry+eye+syndrome:+blinking+tolerance+time+(BTT).">Easy and effective test to evaluate tear-film stability for self-diagnosis of dry eye syndrome: blinking tolerance time (BTT).</a> BMC Ophthalmology. 20 (1), 438 (2020).</li><li>Wolffsohn, J. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demographic+and+lifestyle+risk+factors+of+dry+eye+disease+subtypes:+A+cross-sectional+study.">Demographic and lifestyle risk factors of dry eye disease subtypes: A cross-sectional study.</a> The Ocular Surface. 21, 58-63 (2021).</li></ol>

The author has nothing to disclose.

Several previous studies have reported DES using the Schirmer test, tear break-up time (TBUT), and the OSDI score12. The present study used the AOS software to determine the DES using the limbal redness. One of the important critical protocol steps is to have a clear image of the eyes; if the image is blurry, determining the limbal redness is very challenging, and most likely, accurate readings are not obtained. When all the images are collected, one of the troubleshooting techniques is to check t...

COVID-19, caused by a SARS-COV-2 virus infection, was discovered in Wuhan, China, in December 2019. Meduri et al.1 reported a high prevalence rate of mild ocular symptoms in COVID-19 patients. In Italy, eye surgical procedures were reduced due to the pandemic2. Since the outbreak, many have been working from home and wearing masks as a precaution. Each of these elements and the use of digital devices and online learning3 contributed to dry eye syndrome (DES) and eye strain3,4, respectively. Furthermore, there is evidence that wearing masks can cause DES. Wearing the mask may cause tear evaporation and conjunctival discomfort5. Giannaccare et al. reported that 10.3% of the individuals had rising ocular discomfort symptoms during the pandemic, and the mean score of the OSDI was 21, with a mean age of 28.5 years old6.
A cross-sectional study in Japan reported that the percentage of Japanese women who had a combined result of definite or probable dry eye disease was 76.5%, greater than the percentage of men office employees who utilized Visual Display Terminal7. According to Inomata et al., prolonged screen exposure of more than 8 h/day has been linked to the symptomatic dry eye compared to less than 4 h/day8. The OSDI has proven to be a valid and reliable questionnaire for assessing the severity of DES9,10. The AOS software has been used to determine conjunctival hyperemia, and it has been proven to be a very valid software11.
The present study investigated how common DES is in healthy people aged 20-45. An Ocular Surface Disease Index (OSDI) questionnaire was given to 40 people remotely from October 31, 2021, to December 1, 2021, for conducting the test. The AOS and OSDI surveys were used to assess DES. Finally, the two grading methods were compared: the OSDI score and the AOS software. The participants had to first fill up an eligibility questionnaire, which included the following inclusion criteria: (1) Healthy individuals; (2) Age range of 20-45 years; (3) The participants had to be located in the United States.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AOS SOFTWARE</td>
			<td>Advanced Ophthalmic Systems</td>
			<td>SPARCA</td>
			<td>software to access limbal redness</td>
		</tr>
		<tr>
			<td>Microsoft excel</td>
			<td>Microsoft</td>
			<td></td>
			<td>for data collection and analysis</td>
		</tr>
	</tbody>
</table>

comparing objective conjunctival hyperemia grading and the ocular surface disease index score in dry eye syndrome during covid-19

The incidence of dry eye syndrome (DES) has increased due to wearing masks, utilizing digital devices, and working remotely during the pandemic. A survey was conducted during the COVID-19 pandemic to determine the prevalence of dry eye syndrome. A cross-sectional study investigated how prevalent DES is during COVID-19 in healthy patients aged 20-45 in the United States. An Ocular Surface Disease Index (OSDI) questionnaire was given to 40 individuals remotely from October 31, 2021, to December 1, 2021. The AOS and the OSDI survey were used to evaluate DES. The subjects were 29 years old on average (SD 14.14), with 23 males (57.5%) and 17 females (42.5%). According to the OSDI survey, low DES, moderate DES, and severe DES had prevalence rates of 15%, 77.5%, and 7.5%, respectively. White (W) people represent 50% of the population, while African Americans (AA) represent 35%, Asians represent 7.5%, and Hispanics represent 7.5%. Mild DES affected 77.5% of subjects, with 64.50% males and 35.50% females. According to the AOS objective grading system, mild (M) DES, moderate (MO) DES, and severe (S) DES had prevalence rates of 40%, 12.5%, and 15%, respectively. Linear regression was used to compare the two grading systems, and it demonstrated a strong relationship between the two grading systems.

The subjects were 29 years old on average (mean &#177; SD, 29 &#177; 14.14), with 23 males (57.5%) and 17 females (42.5%) (Table 2). White people account for 50% of the population, while African Americans account for 35%, Asians account for 7.5%, and Hispanics account for 7.5% (Figure 2). The average survey score of the OSDI was 6.17 &#177; 6.24, 37.94 &#177; 5.07, 46 &#177; 0 for low, moderate, and high (Figure 3). According to the OSDI Survey,...

Watch this Scientific Journal Video about Comparing Objective Conjunctival Hyperemia Grading and the Ocular Surface Disease Index Score in Dry Eye Syndrome During COVID-19 at JoVE.com

Comparing Objective Conjunctival Hyperemia Grading and the Ocular Surface Disease Index Score in Dry Eye Syndrome During COVID-19

The present protocol describes the cross-sectional research performed on 40 healthy subjects between the ages of 20 and 45 to assess the prevalence of dry eye syndrome (DES) during COVID-19. The OSDI survey evaluated DES, and the advanced ophthalmic systems (AOS) software was used to assess limbal redness.

The incidence of dry eye syndrome (DES) has increased due to wearing masks, utilizing digital devices, and working remotely during the pandemic. A survey ...

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2.2K Views.  Eye Research Center, Wilmington, DE. The present protocol describes the cross-sectional research performed on 40 healthy subjects between the ages of 20 and 45 to assess the prevalence of dry eye syndrome (DES) during COVID-19. The OSDI survey evaluated DES, and the advanced ophthalmic systems (AOS) software was used to assess limbal redness.

Video: Comparing Objective Conjunctival Hyperemia Grading and the Ocular Surface Disease Index Score in Dry Eye Syndrome During COVID-19

Experimental Glaucoma Induced by Ocular Injection of Magnetic Microspheres

Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present here a protocol for elevating intraocular pressure (IOP) in the rat, by injecting magnetic microspheres into the anterior chamber of the eye. The use of magnetic particles allows the user to manipulate the beads into the iridocorneal angle, thus providing a very effective blockade of fluid outflow from the trabecular meshwork. This leads to long-lasting IOP rises, and eventually neuronal death in the ganglion cell layer (GCL) as well as optic nerve pathology, as seen in patients with the disease. This method is simple to perform, as it does not require machinery, specialist surgical skills, or many hours of practice to perfect. Furthermore, the pressure elevations are very robust, and reinjection of the magnetic microspheres is not usually required unlike in some other models using plastic beads. Additionally, we believe this method is suitable for adaptation for the mouse eye.

We present a method for inducing elevated intraocular pressure (IOP), by injecting magnetic microspheres into the rat eye, to model glaucoma. This leads to strong pressure rises, and extensive neuronal death. This protocol is easy to perform, does not require repeat injections, and produces stable long-lasting IOP rises.

Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present ...

Induction of Nephrotic Syndrome in Mice by Retrobulbar Injection of Doxorubicin and Prevention of Volume Retention by Sustained Release Aprotinin

Nephrotic syndrome is the most extreme manifestation of proteinuric kidney disease and characterized by heavy proteinuria, hypoalbuminemia, and edema due to sodium retention and hyperlipidemia. To study the pathophysiology of this syndrome, rodent models have been developed based on the injection of toxic substances such as doxorubicin causing podocyte damage. In mice, only few strains are susceptible to this model. In wildtype 129S1/SvImJ mice, the administration of doxorubicin by rapid intravenous injection to the retrobulbar sinus induces experimental nephrotic syndrome that features all the symptoms of human disease including sodium retention and edema. After the onset of proteinuria, mice exhibit increased urinary serine protease activity that leads to the activation of the epithelial sodium channel (ENaC) and sodium retention. Pharmacological inhibition of urinary serine proteases by the treatment with sustained release aprotinin abrogates ENaC activation and prevents sodium retention. This model is ideal to study the pathophysiology of proteasuria, i.e., the excretion of active serine proteases that cause ENaC activation by the proteolysis of its &#947;-subunit. This can be regarded as the primary mechanism of ENaC activation and sodium retention in proteinuric kidney disease.

Here, we describe the induction of experimental nephrotic syndrome in 129S1/SvImJ mice by rapid retrobulbar injection of doxorubicin. We also treat nephrotic mice with sustained release pellets containing aprotinin to inhibit urinary serine protease activity and prevent sodium retention.

Nephrotic syndrome is the most extreme manifestation of proteinuric kidney disease and characterized by heavy proteinuria, hypoalbuminemia, and edema due ...

Intense Pulsed Light for the Treatment of Dry Eye Owing to Meibomian Gland Dysfunction

Dry eye disease (DED) is an increasingly common condition and one of the most common complaints of patients. The vast majority of DED is caused by the so-called &#34;evaporative&#34; subtype, that is mainly caused by meibomian gland dysfunction (MGD). Intense pulsed light (IPL) devices employ high intensity pulses of polychromatic lights with a broad range of wavelength (515-1200 nm). IPL treatment has been utilized for years in the field of dermatology, and then its use was applied to ophthalmology for the treatment of MGD. Recently, a new device employing IPL was specifically designed for the periocular application. This procedure determines the thermal selective coagulation and ablation of superficial blood vessels and telangiectasias of the eyelids skin, reducing the release of inflammatory mediators and tear cytokines levels, and improving meibomian glands outflow. IPL treatment is noninvasive and easy to perform, lasts for only a few minutes and can be conducted in an office setting. In the present study, 19 patients underwent 3 sessions of IPL treatment. After treatment, both mean noninvasive break-up time and lipid layer thickness grade significantly increased, as a result of an improvement of tear film stability and quality, respectively. Conversely, no statistically significant changes were found for meibomian gland loss and tear osmolarity. Furthermore, the vast majority of the treated patients (17/19; 89.5% of the total) perceived an improvement of their ocular discomfort symptoms after IPL treatment. Although IPL treatment provides an improvement of both ocular surface parameters and ocular discomfort symptoms after one cycle of three sessions, regular repeated treatments are usually required to maintain the persistence over the time of its beneficial effects.

Dry eye disease is an increasingly common condition, which strongly impair patients&#39; life quality. Recently, a new device employing intense pulsed light, specifically designed for the periocular area, has been shown to improve tear film stability and ocular discomfort symptoms in dry eye disease owing to meibomian gland dysfunction.

Dry eye disease (DED) is an increasingly common condition and one of the most common complaints of patients. The vast majority of DED is caused by the ...

A Rabbit Model of Aqueous-Deficient Dry Eye Disease Induced by Concanavalin A Injection into the Lacrimal Glands: Application to Drug Efficacy Studies

Dry eye disease (DED), a multifactorial inflammatory disease of the ocular surface, affects 1 in 6 humans worldwide with staggering implications for quality of life and health care costs. The lack of informative animal models that recapitulate its key features impedes the search for new therapeutic agents for DED. Available DED animal models have limited reproducibility and efficacy. A model is presented here in which DED is induced by injecting the mitogen concanavalin A (Con A) into the orbital lacrimal glands of rabbits. Innovative aspects of this model are the use of ultrasound (US) guidance to ensure optimal and reproducible injection of Con A into the inferior lacrimal gland; injection of Con A into all orbital lacrimal glands that limits compensatory production of tears; and use of periodic repeat injections of Con A that prolong the state of DED at will. DED and its response to test agents are monitored with a panel of parameters that assess tear production, the stability of the tear film, and the status of the corneal and conjunctival mucosa. They include tear osmolarity, tear break-up time, Schirmer&#39;s tear test, rose bengal staining, and tear lactoferrin levels. The induction of DED and the monitoring of its parameters are described in detail. This model is simple, robust, reproducible, and informative. This animal model is suitable for the study of tear physiology and of the pathophysiology of DED as well as for the assessment of the efficacy and safety of candidate agents for the treatment of DED.

This article describes the development of a method to induce acute or chronic dry eye disease in rabbits by injecting concanavalin A to all portions of the orbital lacrimal gland system. This method, superior to those already reported, generates a reproducible, stable model of dry eye suitable for the study of pharmacological agents.

Dry eye disease (DED), a multifactorial inflammatory disease of the ocular surface, affects 1 in 6 humans worldwide with staggering implications for ...

Transaxillary First Rib Resection for Treatment of the Thoracic Outlet Syndrome

Thoracic outlet syndrome (TOS) is a common disorder that causes a significant loss of productivity. The transaxillary first rib resection (TFRR) protocol has been used for the decompression of trapped neurovascular structures in the TOS. Among the other surgical procedures, the advantage of the TFRR is that it has the smallest rate of recurrence and better cosmetic outcomes. The disadvantage of TFRR is that it provides a narrow, and deep working corridor that makes obtaining vascular control challenging.

Here, we present a protocol of the transaxillary resection of the first rib for treatment of thoracic outlet syndrome caused by compression of the brachial plexus, subclavian vein and artery.

Thoracic outlet syndrome (TOS) is a common disorder that causes a significant loss of productivity. The transaxillary first rib resection (TFRR) protocol ...

Inverse Probability of Treatment Weighting (Propensity Score) using the Military Health System Data Repository and National Death Index

When randomized controlled trials are not feasible, retrospective studies using big data provide an efficient and cost-effective alternative, though they are at risk for treatment selection bias. Treatment selection bias occurs in a non-randomized study when treatment selection is based on pre-treatment characteristics that are also associated with the outcome. These pre-treatment characteristics, or confounders, can influence evaluation of a treatment&#39;s effect on the outcome. Propensity scores minimize this bias by balancing the known confounders between treatment groups. There are a few approaches to performing propensity score analyses, including stratifying by the propensity score, propensity matching, and inverse probability of treatment weighting (IPTW). Described here is the use of IPTW to balance baseline comorbidities in a cohort of patients within the US Military Health System Data Repository (MDR). The MDR is a relatively optimal data source, as it provides a contained cohort in which nearly complete information on inpatient and outpatient services is available for eligible beneficiaries. Outlined below is the use of the MDR supplemented with information from the national death index to provide robust mortality data. Also provided are suggestions for using administrative data. Finally, the protocol shares an SAS code for using IPTW to balance known confounders and plot the cumulative incidence function for the outcome of interest.

Inverse Probability of Treatment Weighting Propensity Score using the Military Health System Data Repository and National Death Index

When randomized controlled trials are not feasible, a comprehensive health care data source like the Military Health System Data Repository provides an attractive alternative for retrospective analyses. Incorporating mortality data from the national death index and balancing differences between groups using propensity weighting helps reduce biases inherent in retrospective designs.

When randomized controlled trials are not feasible, retrospective studies using big data provide an efficient and cost-effective alternative, though they ...

Customizing a Cryolite Glass Prosthetic Eye

In Germany, Austria, and Switzerland, over 90% of ocularists still manufacture customized prostheses using cryolite glass from Thuringia. The present manuscript demonstrates this long-forgotten technique in detail. This manuscript shows some major advantages of manufacturing prosthetic eyes using cryolite glass in comparison to poly(methyl methacrylate) (PMMA). These advantages include a lighter weight of the prosthesis, higher levels of patient satisfaction, and only one appointment necessary for the customized manufacturing. Potential risk of breakage seems not to be a critical disadvantage for glass prosthetic eye wearers. However, in some patients, manufacturing a well-fitting prosthetic eye is not possible or reasonable due to anophthalmic socket complications such as post nucleation socket syndrome, scarred fornices, or an orbital implant exposure. This article gives ophthalmologists a better insight into ocularistic care in order to improve the essential interprofessional collaboration between ocularists and ophthalmologists.

This manuscript shows each step of customizing a cryolite glass prosthetic eye including some major advantages of the use of cryolite glass for manufacturing an eye prosthesis compared to poly(methyl methacrylate). In addition, this manuscript gives ophthalmologists better insight into the ocularistic care that could improve interprofessional collaboration.

In Germany, Austria, and Switzerland, over 90% of ocularists still manufacture customized prostheses using cryolite glass from Thuringia. The present ...

Establishment of a Severe Dry Eye Model Using Complete Dacryoadenectomy in Rabbits

Dry eye disease (DED) is a complex disease with multiple etiologies and variable symptoms, having ocular surface inflammation as its key pathophysiologic step. Despite advances in our understanding of DED, significant knowledge gaps remain. Advances are limited in part due to the lack of informative animal models. The authors recently reported on a method of DED induced by injecting all orbital lacrimal gland (LG) tissues with the lectin concanavalin A. Here, we report a novel model of aqueous-deficient DED based on the surgical resection of all orbital LG (dacryoadenectomy) tissues. Both methods use rabbits because of their similarity to human eyes in terms of the size and structure of the ocular surface. One week after removal of the nictitating membrane, the orbital superior LG was surgically removed under anesthesia, followed by removal of the palpebral superior LG, and finally removal of the inferior LG. Dacryoadenectomy induced severe DED, evidenced by a marked reduction in the tear break up time test and the Schirmer&#39;s tear test, and significantly increased tear osmolarity and rose bengal staining. Dacryoadenectomy-induced DED lasted at least eight weeks. There were no complications and animals tolerated the procedure well. The technique can be mastered relatively easily by those with adequate surgical experience and appreciation of the relevant rabbit anatomy. Since this model recapitulates the features of human aqueous-deficient DED, it is suitable for studies of ocular surface homeostasis, DED, and candidate therapeutics.

A novel approach is presented to induce chronic dry eye disease in rabbits by surgically removing all orbital lacrimal glands. This method, distinct from those previously reported, produces a stable, reproducible model of aqueous deficient dry eye well suited to study tear physiology and pathophysiology and ocular therapeutics.

Dry eye disease (DED) is a complex disease with multiple etiologies and variable symptoms, having ocular surface inflammation as its key pathophysiologic ...

Using an Automated Hirschberg Test App to Evaluate Ocular Alignment

A smartphone app has been developed to perform the automated photographic Hirschberg test for objective measurement of ocular misalignment. By computing the difference in corneal reflection generated by the phone camera flash relative to the iris center based on high resolution images, the app can measure misalignment with a much higher precision than the naked eye performing the Hirschberg test. It has been validated in a previous clinical evaluation study by comparing to the clinical gold standard-prism and alternate cover test. The goal of this article is to describe the testing techniques regarding how to use the app to measure ocular alignment for different fixation distances, without or with cover to break fusion, as well as angle kappa, so that users can use the app to perform equivalent tests typically done in clinic using prisms.

We present a protocol of using a smartphone app to perform Hirschberg test for measuring manifest and intermittent ocular misalignment (strabismus) under near and far fixation conditions.

A smartphone app has been developed to perform the automated photographic Hirschberg test for objective measurement of ocular misalignment. By computing ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...