The authors wish to thank &#34;Casa del Dono di Reggio Emilia&#34; for providing donor-derived platelet concentrates.

PRP-L used for the quantitative assessment of growth factors were collected within a wider study on the characterization of PRP products for regenerative purposes, carried out at the AUSL-IRCCS di Reggio Emilia and approved by the Area Vasta Emilia Nord Ethical Committee on 10 January, 2019 (protocol number 2019/0003319). Donors gave their informed consent as per the Declaration of Helsinki. No ethical approval was necessary for collecting the aggregated, anonymous data of the Ocular Surface Disease Index (OSDI) questionnaire, which is routinely used by clinicians to monitor dry eye syndrome symptoms. Figure 1A shows an outline of the protocol followed, while the pictures in Figure 1B depict the main steps of the procedure.
1. Platelet-rich plasma (PRP) collection
<ol>
	<li>PRP apheresis
	<ol>
		<li>For this protocol, select platelet donors according to Italian laws: platelet donors must be 18-65 years old, with normal pressure and blood count parameters and a platelet count not less than 180 x 109 platelets/L23. Eligible donors cannot take antiplatelet or anticoagulant drugs within 1 week before donation.</li>
		<li>Perform plasma-platelet-apheresis using an automated blood collection system, according to the manufacturers&#39; instructions and national laws23, to obtain 1 unit of single-donor platelet-rich plasma (PRP). Collect PRP in Adenine Citrate Dextrose Solution A (ACD-A) anticoagulant solution. 
		NOTE: Platelet-apheresis is conducted with a continuous procedure; the time of collection is in a range between 40 min and 90 min. The amount of ACD delivered to the donors and the time of the procedures depend on the donor characteristics, e.g., hematocrit and needle gauge.</li>
	</ol>
	</li>
	<li>PRP units&#39; characteristics 
	NOTE: The following step is usually performed automatically by the automated blood collection system during the plasma-platelet-apheresis procedure. Please check the manufacturer&#39;s manual of instruction.
	<ol>
		<li>Resuspend the PRP units collected by apheresis in an adequate amount of preservative solution with the minimum amount of residual plasma, necessary to maintain pH &#62; 6.4 during the whole storage time, to a mean final volume of 180 mL net of the anticoagulant solution (around 40 mL). 
		NOTE: According to Italian law, quality controls have to assess that the platelet (PLTs) count is at least 2.0 x 1011 PLTs/unit, while residual leucocytes have to be less than 1 x 106 cells/unit.</li>
		<li>Store leucodepleted and irradiated PRP for a maximum of 5 days at 22 &#176;C &#177; 2 &#176;C on a platelet shaker before further manipulation23.</li>
	</ol>
	</li>
	<li>PRP dilution
	<ol>
		<li>Immediately before starting PRP dilution, perform a PLT count with a hemocytometer using the sample collected from the main bag through a piercing spike. 
		NOTE: Perform the next steps in sterility under a class II biohazard hood. Wear personal protection equipment (lab coat, gloves, and goggles) during the procedure.</li>
		<li>Dilute PRP with an adequate amount of sterile 0.9% NaCl to a final concentration of 0.32 x 109 &#177; 0.03 x 109 PLTs/mL, which simulates the average PLT concentration in peripheral blood.</li>
		<li>Taking advantage of a piercing spike for blood bags, split the diluted PRP into 300 mL empty collection bags to reach a net volume of 190 mL/bag.</li>
		<li>Use an aliquot of residual diluted PRP (usually 1 mL) to perform quality controls assessing possible microbial contaminations. Perform a sterility assay following the manufacturer&#39;s instructions in a microbiology laboratory (see Table of Materials). 
		NOTE: Use culture vials specific for aerobic blood cultures, which are able to perform the qualitative culture and recovery of aerobic microorganisms (mainly bacteria and yeast) from small volume blood specimens.</li>
		<li>Store diluted PRP bags at &#8722;80 &#176;C for a maximum of 2 months before thawing.</li>
	</ol>
	</li>
</ol>
2. Platelet-rich plasma lysate (PRP-L) preparation
<ol>
	<li>Thawing
	<ol>
		<li>Before starting the thawing procedure, ensure that a warm bath is set at 37 &#176;C. Put the PRP bags into the warm bath and wait until completely thawed.</li>
	</ol>
	</li>
	<li>PRP-L collection
	<ol>
		<li>Centrifuge the PRP bags at 3000 x g for 30 min at room temperature. 
		&#8203;NOTE: The next steps should be performed in sterility under a class II biohazard hood.</li>
		<li>Exploiting the piercing spike of the transfer bag, connect the centrifuged bag with an empty sterile 300 mL transfer bag. Carefully, transfer the PRP-L supernatant, while avoiding debris, into the new bag. When possible, use a bag press.</li>
		<li>Seal the connection tube of the PRP-L unit with a bag sealer.</li>
	</ol>
	</li>
	<li>PRP-L aliquotation 
	NOTE: A starting unit containing 190 mL PRP (see step 1.3.3.) is sufficient to fill two eye drops kits (for details on the specific medical devices used for the application and preservation of eye drops from blood components, see the Table of Materials). Eye drops kits should be opened under a class II hood with the whole string vials positioned above the pre-connected syringe and the central arrow of the stopcock pointing leftward to exclude the anti-bacterial filter.
	<ol>
		<li>Collect 30-60 mL of PRP-L with a sterile syringe and link the syringe to the Luer/lock connection on the filling line.</li>
		<li>According to the manufacturer&#39;s instructions, turn the stopcock by half of a turn to open the line between the PRP-L-containing syringe and the pre-connected syringe. Fill the pre-connected syringe with PRP-L.</li>
		<li>Disconnect the PRP-L syringe, close the tube cap of the luer/lock connection and rotate the stopcock to the original position. Use the eye drops kit syringe to fill the vials with PRP-L.</li>
		<li>Repeat the procedure from steps 2.3.1.-2.3.3. until all the applicator vials are filled. Ensure that each applicator is properly filled, then individually seal them with a bag sealer.</li>
		<li>Repeat the procedure with a new eye drops kit.</li>
		<li>Use a small aliquot of residual diluted PRP-L to assess possible microbial contamination (see step 1.3.4.). 
		NOTE: If the liquid accidentally reaches the anti-bacterial filter at the end of the string, the suction syringe may oppose resistance, hindering the filling. To continue the filling cycle, raise the end section of the string for about 5/6 aliquots from the anti-bacterial hydrophobic filter at the end of the string. In this position, use a new sterile syringe (of 30 mL volume) that has already been filled with air. Connect the female luer/lock of the anti-bacterial filter and press hard and repeatedly on the syringe&#39;s plunger to remove all residues of blood component and render the membrane of the anti-bacterial filter free of the liquid. Remove the syringe and fill the remaining vials.</li>
	</ol>
	</li>
	<li>PRP-L storage
	<ol>
		<li>Properly label each applicator and put them into a plastic bag. Label the plastic bag too, taking care to highlight the donor&#39;s blood group.</li>
		<li>Store at &#8722;80 &#176;C for a maximum of 24 months before patient assignment, according to the Italian law23 and guidelines24.</li>
	</ol>
	</li>
</ol>
3. PRP-L dispensation
<ol>
	<li>Perform patient assignment preferably by matching the PRP-L blood group. Deliver PRP-L applicator vials using a cool box and ensure that each applicator vial contains 1.45 mL of PRP-L, which corresponds to approximately 45 drops. Instruct the patient that applicator vials can be stored at the patients&#39; homes for up to 1 month at &#8722;15 &#176;C.</li>
</ol>

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The authors declare no conflicts of interest.

In recent years, the clinical use of platelet-based products for ocular surface pathologies has increased, but their diffusion is hampered by the lack of scientific robustness. This is mainly caused by wide heterogeneity in donor sources and preparation protocols, which are often not fully disclosed or not specifically designed for the purpose for which they are dispensed. Particularly, information about platelet-based products collected by apheresis is still lacking. Therefore, the aim of the present work was to describ...

Blood-derived products are widely used in wound care1, maxillofacial and orthopedic surgery, and for the treatment of different ocular surface diseases2 such as dry eye disease (DED)3. In DED, the tear film homeostasis is impaired as a consequence of the abnormal functioning of different factors involved in tear production and ocular surface integrity4,5.
DED is characterized by heterogeneity in causes and severity6,7,8 and may be a consequence of different factors like aging, sex9, contact lenses, topical or systemic medications10, or pre-existing conditions like Sj&#246;gren&#39;s syndrome10. Despite having mild symptoms, DED affects millions of people worldwide, impacting their quality of life and the health system as well6.
Many treatments have been reported for this pathology, but there is still no consensus on the most effective solution12. To date, artificial tears are the first line of therapy aimed at restoring the aqueous composition of the tear film, albeit these substitutes do not contain the main biologically active solutes of natural tears6,11. Platelet-based products are considered a valid alternative12,13 to artificial tears, although their clinical efficacy, recommendations for use, and methods of preparations are still a matter of debate3.
Blood-based products share with tears a similar composition in terms of metabolites14, proteins, lipids, vitamins, ions, growth factors (GFs), antioxidant compounds11 and osmolarity (300 mOsm/L)11. Through the synergistic activity of their components, they promote the regeneration of the corneal epithelium, inhibit the release of inflammatory cytokines, and increase the number of goblet cells and the expression of mucins in the conjunctiva2,3.
So far, heterogeneity in ophthalmic blood-based products has been documented in the literature; these products can be classified according to the blood donors&#39; origin, i.e., autologous, or allogenic, as well as the blood source, i.e., peripheral blood, cord blood, serum, or platelets.
Although autologous products were the most widespread3, allogenic ones are now becoming the preferred choice, since they ensure higher efficacy and safety standards15, together with a significant reduction in costs16,17. Previous studies, indeed, proved that blood-based products obtained from patients with autoimmune and/or systemic diseases may show altered quality and functionality6,16,17. Despite the fact that serum-based eye drops are the most widespread, platelets-based products are recently becoming affirmed as a valid alternative, as they can be easily prepared while maintaining significant levels of efficacy3,11. Currently available platelet-based products can be divided in platelet-rich plasma (PRP), platelet-rich plasma lysate (PRP-L), and plasma rich in growth factors (PRGF)3.
Among them, PRP-L has the advantage of being a long-life frozen product. PRP-L can be prepared from apheresis, buffy-coats, or even from expiring platelets (PLTs)18,19, preciously reducing their wastage. The aliquots can be stored for months in the blood transfusions centers at &#8722;80 &#176;C or even at patients&#39; homes at &#8722;15 &#176;C for shorter periods.
PRP-L are highly enriched in GFs, which have been proved to stimulate eye surface regeneration12,20,21. Nevertheless, there are only few reported clinical studies in this area, and all of them used autologous sources3,22. PRP-L still needs further validation and characterization before it can be routinely used for the treatment of eye surface diseases, since there are no standardized guidelines for its preparation, dispensation, and storage3.
Herein, a detailed protocol is shared for the production of PRP-L used at the Transfusion Medicine Unit in AUSL-IRCCS di Reggio Emilia, Italy, and dispensation to patients with DED. We aim to help the scientific community to develop standard methods of preparation, which may increase homogeneity and consistency in worldwide studies and clinical approaches.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Equipments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>CompoSeal Mobilea II</td>
			<td>Fresenius Kabi, Germany</td>
			<td></td>
			<td>bag sealer</td>
		</tr>
		<tr>
			<td>HeraSafe hood</td>
			<td>Heraeus Instruments, Germany</td>
			<td></td>
			<td>Class II biohazard hood</td>
		</tr>
		<tr>
			<td>MCS+ 9000 Mobile Platelet Collection System</td>
			<td>Haemonetics, Italy</td>
			<td></td>
			<td>automated plasma and multicomponent collection equipment for donating platelet, red cell, plasma, or combination blood components</td>
		</tr>
		<tr>
			<td>Platelet shaker, PF396i</td>
			<td>Helmer, USA</td>
			<td></td>
			<td>Platelet shaker</td>
		</tr>
		<tr>
			<td>Raycell X-ray Blood Irradiator</td>
			<td>MDS Nordion, Canada</td>
			<td></td>
			<td>X-ray Blood Irradiator</td>
		</tr>
		<tr>
			<td>ROTIXA 50RS</td>
			<td>Hettich Zentrifugen, Germany</td>
			<td></td>
			<td>High speed entrifuge</td>
		</tr>
		<tr>
			<td>Sysmex XS-1000i</td>
			<td>Sysmex Europe GMBH, Germany</td>
			<td></td>
			<td>haemocytometer for platelet count</td>
		</tr>
		<tr>
			<td>Warm bath, WB-M15</td>
			<td>Falc Instruments, Italy</td>
			<td></td>
			<td>Warm bath</td>
		</tr>
		<tr>
			<td>Materials</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>ACD-A anticoagulant solution A</td>
			<td>Fenwal Inc., USA</td>
			<td>DIN 00788139</td>
			<td>anticoagulant solution for platelet apheresis (1000 ml)</td>
		</tr>
		<tr>
			<td>BD BACTEC Peds Plus/F Culture vials</td>
			<td>BD Biosciences, USA</td>
			<td>BD 442020</td>
			<td>Sterility assay</td>
		</tr>
		<tr>
			<td>BD BACTEC Peds Plus/F Culture vials</td>
			<td>BD Biosciences, USA</td>
			<td>442020</td>
			<td>At least 2 vials for sterility assay</td>
		</tr>
		<tr>
			<td>BD Luer Lok Syringe</td>
			<td>BD Plastipack, USA</td>
			<td>300865</td>
			<td>At least 4 sterile syringes (50 ml)</td>
		</tr>
		<tr>
			<td>Bio-Plex Human Cancer Panel 1</td>
			<td>BioRad Laboratories, USA</td>
			<td>171AC500M</td>
			<td>Standard panel for PDGF isoforms assessment</td>
		</tr>
		<tr>
			<td>Bio-Plex Human Cancer Panel 2</td>
			<td>BioRad Laboratories, USA</td>
			<td>171AC600M</td>
			<td>Standard panel for EGF assessment</td>
		</tr>
		<tr>
			<td>Bio-Plex MAGPIX Multiplex Reader</td>
			<td>BioRad Laboratories, USA</td>
			<td>Magpix</td>
			<td>This instrument allows multiple immunoassays using functionalized magnetic beads.</td>
		</tr>
		<tr>
			<td>Bio-Plex Pro TGF-b Assay</td>
			<td>BioRad Laboratories, USA</td>
			<td>10024984</td>
			<td>Set and standards for TGFb isoforms assessment</td>
		</tr>
		<tr>
			<td>BioRet</td>
			<td>ARIES s.r.l., Italy</td>
			<td>A2DH0020</td>
			<td>At least 4 piercing spike for blood bags</td>
		</tr>
		<tr>
			<td>Blood collection tube</td>
			<td>BD Vacutainer, USA</td>
			<td>367835</td>
			<td>1 tube, necessary to perform platelet counts</td>
		</tr>
		<tr>
			<td>Eye drops kit. COL Medical Device for the application and preservation of eye drops from haemocomponents</td>
			<td>Biomed Device s.r.l., Italy</td>
			<td>COLC50</td>
			<td>Eye drops kit. At least 2 kits for each PRP unit collected</td>
		</tr>
		<tr>
			<td>Human Cancer PDGF-AB/BB Set 1x96well</td>
			<td>BioRad Laboratories, USA</td>
			<td>171BC511</td>
			<td>Set for PDGF isoforms assessment</td>
		</tr>
		<tr>
			<td>Human Cancer2 EGF Set 1x96well</td>
			<td>BioRad Laboratories, USA</td>
			<td>171BC603M</td>
			<td>Set for EGF assessment</td>
		</tr>
		<tr>
			<td>NaCl 0.9% sterile solution</td>
			<td>Baxter S.p.A., Italy</td>
			<td>B05BB01</td>
			<td>1000 ml</td>
		</tr>
		<tr>
			<td>OSDI Questionnaire</td>
			<td>Allergan Inc., USA</td>
			<td>OSDI</td>
			<td>Ocular Surface Disease Index Questionnaire</td>
		</tr>
		<tr>
			<td>Piercing spike</td>
			<td>BioRet ARIES s.r.l., Italy</td>
			<td>BS051004</td>
			<td>Spike</td>
		</tr>
		<tr>
			<td>Platelet Additive Solution A+ T-PAS+</td>
			<td>TERUMO BCT Inc., Italy</td>
			<td>40842</td>
			<td>preservative solution for platelet concentrates (1000 ml)</td>
		</tr>
		<tr>
			<td>Software Excel</td>
			<td>Microsoft, USA</td>
			<td>Excel</td>
			<td>Data analysis software</td>
		</tr>
		<tr>
			<td>Teruflex Transfer bag 1000 ml</td>
			<td>TERUMO BCT Inc., Italy</td>
			<td>BB*T100BM</td>
			<td>1 for PRP dilution</td>
		</tr>
		<tr>
			<td>Teruflex Transfer bag 300 ml</td>
			<td>TERUMO BCT Inc., Italy</td>
			<td>BB*030CM</td>
			<td>At least 6 for each PRP unit collected</td>
		</tr>
	</tbody>
</table>

platelet-rich plasma lysate for treatment of eye surface diseases

Various ocular surface diseases are treated with blood-derived eye drops. Their use has been introduced in clinical practice because of their metabolite and growth factor content, which promotes eye surface regeneration. Blood-based eye drops can be prepared from different sources (i.e., whole blood or platelet apheresis donation), as well as with different protocols (e.g., different dilutions and freeze/thaw cycles). This variability hampers the standardization of clinical protocols and, consequently, the evaluation of their clinical efficacy. Detailing and sharing the methodological procedures may contribute to defining common guidelines. Over the last years, allogenic products have been diffusing as an alternative to the autologous treatments since they guarantee higher efficacy standards; among them, the platelet-rich plasma lysate (PRP-L) eye drops are prepared with simple manufacturing procedures. In the transfusion medicine unit at AUSL-IRCCS di Reggio Emilia, Italy, PRP-L is obtained from platelet-apheresis donation. This product is initially diluted to 0.3 x 109 platelets/mL (starting from an average concentration of 1 x 109 platelets/mL) in 0.9% NaCl. Diluted platelets are frozen/thawed and, subsequently, centrifuged to eliminate debris. The final volume is split into 1.45 mL aliquots and stored at &#8722;80 &#176;C. Before being dispensed to patients, eye drops are tested for sterility. Patients may store platelet lysates at &#8722;15 &#176;C for up to 1 month. The growth factor composition is also assessed from randomly selected aliquots, and the mean values are reported here.

The rationale for the use of serum-derived eye drops (which is the blood-based product most frequently used for the treatment of eye surface diseases) lies in their content of GFs, which are almost completely derived from circulating platelets. PRP contains a significantly higher number of platelets (and, consequently, of platelet-derived GFs) compared to peripheral blood serum, ranging between 0.15 x 109-0.45 x 109 PLTs/mL. According to Italian laws, the platelet count in PRP units should be at lea...

Watch this Scientific Journal Video about Platelet-Rich Plasma Lysate for Treatment of Eye Surface Diseases at JoVE.com

Platelet-Rich Plasma Lysate for Treatment of Eye Surface Diseases

Platelet lysates represent an emerging tool for the treatment of ocular surface diseases. Here, we propose a method for the preparation, dispensation, storage, and characterization of platelet lysate collected from platelet donors.

Various ocular surface diseases are treated with blood-derived eye drops. Their use has been introduced in clinical practice because of their metabolite ...

platelet-rich-plasma-lysate-for-treatment-of-eye-surface-diseases

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3.8K Views.  AUSL-IRCCS di Reggio Emilia. Platelet lysates represent an emerging tool for the treatment of ocular surface diseases. Here, we propose a method for the preparation, dispensation, storage, and characterization of platelet lysate collected from platelet donors.

Video: Platelet-Rich Plasma Lysate for Treatment of Eye Surface Diseases

Quantitative Fundus Autofluorescence for the Evaluation of Retinal Diseases

The retinal pigment epithelium (RPE) is juxtaposed to the overlying sensory retina, and supports the function of the visual system. Among the tasks performed by the RPE are phagocytosis and processing of outer photoreceptor segments through lysosome-derived organelles. These degradation products, stored and referred to as lipofuscin granules, are composed partially of bisretinoids, which have broad fluorescence absorption and emission spectra that can be detected clinically as fundus autofluorescence with confocal scanning laser ophthalmoscopy (cSLO). Lipofuscin accumulation is associated with increasing age, but is also found in various patterns in both acquired and inherited degenerative diseases of the retina. Thus, studying its pattern of accumulation and correlating such patterns with changes in the overlying sensory retina are essential to understanding the pathophysiology and progression of retinal disease. Here, we describe a technique employed by our lab and others that uses cSLO in order to quantify the level of RPE lipofuscin in both healthy and diseased eyes.

The retinal pigment epithelium (RPE) supports the sensory retina through recycling visual cycle byproducts, which accumulate as lipofuscin. These products are autofluorescent and can be qualitatively imaged in vivo. Here, we describe a method to quantitatively image RPE lipofuscin using confocal scanning laser ophthalmoscopy.

The retinal pigment epithelium (RPE) is juxtaposed to the overlying sensory retina, and supports the function of the visual system. Among the tasks ...

Effects of Allogeneic Platelet-Rich Plasma (PRP) on the Healing Process of Sectioned Achilles Tendons of Rats: A Methodological Description

This article describes the experimental procedures used to observe if PRP can positively affect tendon healing. There are 4 main steps to follow: induce a lesion in the Achilles tendon; prepare PRP and inject it (or the saline solution); remove the tendon; and perform biomechanical, molecular, and histological evaluations. At each step, all the procedures and methods are described in detail, so they can be reproduced easily.
Achilles tendons have been surgically sectioned (removal of a 5-mm long section). Afterwards, PRP or saline solution was injected to study whether PRP has a positive effect on the healing of the tendon. Three groups of 40 animals (a total of 120 rats were used in this study) were subdivided into 2 subgroups: PRP injection group and a saline injection control group. Rats were sacrificed at increasing time points (Group A: 5 days; Group B: 15 days; Group C: 30 days) and tendons were removed. 90 tendons underwent biomechanical testing before performing transcriptomic analysis and the 30 remaining tendons were submitted to histological analysis.

Effects of Allogeneic Platelet-Rich Plasma PRP on the Healing Process of Sectioned Achilles Tendons of Rats: A Methodological Description

This protocol describes the evaluation process of healing tendons in rats that have been injected with allogeneic platelet rich plasma (PRP) or saline solution after removing part of the Achilles tendon. The progress of tendon healing is evaluated at several time points using different types of analyses.

This article describes the experimental procedures used to observe if PRP can positively affect tendon healing. There are 4 main steps to follow: induce a ...

Preparation, Procedures and Evaluation of Platelet-Rich Plasma Injection in the Treatment of Knee Osteoarthritis

Knee osteoarthritis (KOA) is one of the most frequently encountered diseases in the orthopedic department. Existing non-surgical treatments have a limited effect on the repair of cartilage and on bone regeneration. Platelet-rich plasma (PRP) is an autologous bioactive substance that can repair cartilage injury and accelerate bone regeneration effectively. However, reporting of PRP preparation protocols in clinical studies is highly inconsistent, with the majority of studies providing insufficient information to allow the protocol to be reproduced. We describe a repeatable method of preparing PRP visually, the treatment of KOA using PRP intra-articular injection, and methods of evaluating the outcome. PRP was prepared using manual double centrifugation. The PRP layer was extracted from peripheral blood and used for knee joint cavity injection. Evaluations included assessments of blood platelet concentrations and clinical outcomes. Preparation of PRP by manual centrifugation requires less apparatus and is less costly than plasma filtration or centrifugation using equipment. The centrifugation time of our double centrifugation method was 6 and 5 minutes for the respective centrifugations at forces of 800 and 1400 x g, respectively, to allow for the consistent preparation of standardized PRP. However, a manual method is susceptible to operator error, and PRP batch preparation is not available. Intra-articular injection of PRP proved to be an effective treatment for knee osteoarthritis. The entire treatment procedure took less than 30 minutes, the blood platelet concentration of PRP could be standardized, and treatment was proven to be effective when evaluated by follow-up.

Knee osteoarthritis is frequently seen in the orthopedic department. We introduce in detail the entire knee osteoarthritis treatment process with platelet-rich plasma injection, including preparation, procedures, and evaluation.

Knee osteoarthritis (KOA) is one of the most frequently encountered diseases in the orthopedic department. Existing non-surgical treatments have a limited ...

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 ...

Oxygen-Induced Retinopathy Model for Ischemic Retinal Diseases in Rodents

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR model induction and its readouts in both mice and rats. Retinal neovascularization is induced in OIR by exposing rodent pups either to hyperoxia (mice) or alternating levels of hyperoxia and hypoxia (rats). The primary readouts of these models are the size of neovascular (NV) and avascular (AVA) areas in the retina. This preclinical in vivo model can be used to evaluate the efficacy of potential anti-angiogenic drugs or to address the role of specific genes in the retinal angiogenesis by using genetically manipulated animals. The model has some strain and vendor specific variation in the OIR induction which should be taken into consideration when designing the experiments.

Oxygen-induced retinopathy (OIR) can be used to model ischemic retinal diseases such as retinopathy of prematurity and proliferative diabetic retinopathy and to serve as a model for proof-of-concept studies in evaluating antiangiogenic drugs for neovascular diseases. OIR induces robust and reproducible neovascularization in the retina that can be quantified.

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR ...

Retinal Pigment Epithelium Transplantation in a Non-human Primate Model for Degenerative Retinal Diseases

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These conditions include retinitis pigmentosa (RP) and advanced forms of age-related macular degeneration (AMD), such as geographic atrophy (GA). Together, these disorders represent a significant proportion of currently untreatable blindness globally. These unmet medical needs have generated heightened academic interest in developing methods of RPE replacement. Among the animal models commonly utilized for preclinical testing of therapeutics, the non-human primate (NHP) is the only animal model that has a macula. As it shares this anatomical similarity with the human eye, the NHP eye is an important and appropriate preclinical animal model for the development of advanced therapy medicinal products (ATMPs) such as RPE cell therapy.
This manuscript describes a method for the submacular transplantation of an RPE monolayer, cultured on a polyethylene terephthalate (PET) cell carrier, underneath the macula onto a surgically created RPE wound in immunosuppressed NHPs. The fovea-the central avascular portion of the macula-is the site of the greatest mechanical weakness during the transplantation. Foveal trauma will occur if the initial subretinal fluid injection generates an excessive force on the retina. Hence, slow injection under perfluorocarbon liquid (PFCL) vitreous tamponade is recommended with a dual-bore subretinal injection cannula at low intraocular pressure (IOP) settings to create a retinal bleb. 
Pretreatment with an intravitreal plasminogen injection to release parafoveal RPE-photoreceptor adhesions is also advised. These combined strategies can reduce the likelihood of foveal tears when compared to conventional techniques. The NHP is a key animal model in the preclinical phase of RPE cell therapy development. This protocol addresses the technical challenges associated with the delivery of RPE cellular therapy in the NHP eye.

The non-human primate (NHP) is an ideal model for studying human retinal cellular therapeutics due to the anatomical and genetic similarities. This manuscript describes a method for submacular transplantation of retinal pigment epithelial cells in the NHP eye and strategies to prevent intraoperative complications associated with macular manipulation.

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These ...

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 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 ...

The Miniature Pig: A Large Animal Model for Cochlear Implant Research

Cochlear implants (CI) are the most effective method to treat people with severe-to-profound sensorineural hearing loss. Although CIs are used worldwide, no standard model exists for investigating the electrophysiology and histopathology in patients or animal models with a CI or for evaluating new models of electrode arrays. A large animal model with cochlea characteristics similar to those of humans may provide a research and evaluation platform for advanced and modified arrays before their use in humans. 
To this end, we established standard CI methods with Bama mini-pigs, whose inner ear anatomy is highly similar to that of humans. Arrays designed for human use were implanted into the mini pig cochlea through a round window membrane, and a surgical approach followed that was similar to that used for human CI recipients. Array insertion was followed by evoked compound action potential (ECAP) measurements to evaluate the function of the auditory nerve. This study describes the preparation of the animal, surgical steps, array insertion, and intraoperative electrophysiological measurements. 
The results indicated that the same CI used for humans could be easily implanted in mini-pigs via a standardized surgical approach and yielded similar electrophysiological outcomes as measured in human CI recipients. Mini-pigs could be a valuable animal model to provide initial evidence of the safety and potential performance of novel electrode arrays and surgical approaches before applying them to human beings.

Miniature pigs (mini-pigs) are an ideal large animal model for research into cochlear implants. Cochlear implantation surgery in mini-pigs can be utilized to provide initial evidence of the safety and potential performance of novel electrode arrays and surgical approaches in a living system similar to human beings.

Cochlear implants (CI) are the most effective method to treat people with severe-to-profound sensorineural hearing loss. Although CIs are used worldwide, ...

Retinal Explant of the Adult Mouse Retina as an Ex Vivo Model for Studying Retinal Neurovascular Diseases

One of the challenges in retina research is studying the cross-talk between different retinal cells such as retinal neurons, glial cells, and vascular cells. Isolating, culturing, and sustaining retinal neurons in vitro have technical and biological limitations. Culturing retinal explants may overcome these limitations and offer a unique ex vivo model to study the cross-talk between various retinal cells with well-controlled biochemical parameters and independent of the vascular system. Moreover, retinal explants are an effective screening tool for studying novel pharmacological interventions in various retinal vascular and neurodegenerative diseases such as diabetic retinopathy. Here, we describe a detailed protocol for retinal explants' isolation and culture for an extended period. The manuscript also presents some of the technical problems during this procedure that may affect the desired outcomes and reproducibility of the retinal explant culture. The immunostaining of the retinal vessels, glial cells, and neurons demonstrated intact retinal capillaries and neuroglial cells after 2 weeks from the beginning of the retinal explant culture. This establishes retinal explants as a reliable tool for studying changes in the retinal vasculature and neuroglial cells under conditions that mimic retinal diseases such as diabetic retinopathy.

Retinal Explant of the Adult Mouse Retina as an Ex Vivo Model for Studying Retinal Neurovascular Diseases

This protocol presents and describes steps for the isolation, dissection, culturing, and staining of retinal explants obtained from an adult mouse. This method is beneficial as an ex vivo model for studying different retinal neurovascular diseases such as diabetic retinopathy.

One of the challenges in retina research is studying the cross-talk between different retinal cells such as retinal neurons, glial cells, and vascular ...

Plasma Polishing as a New Polishing Option to Reduce the Surface Roughness of Porous Titanium Alloy for 3D Printing

Porous titanium alloy implants with simulated trabecular bone fabricated by 3D printing technology have broad prospects. However, due to the fact that some powder adheres to the surface of the workpiece during the manufacturing process, the surface roughness in direct printing pieces is relatively high. At the same time, since the internal pores of the porous structure cannot be polished by conventional mechanical polishing, an alternative method needs to be found. As a surface technology, plasma polishing technology is especially suitable for parts with complex shapes that are difficult to polish mechanically. It can effectively remove particles and fine splash residues attached to the surface of 3D printed porous titanium alloy workpieces. Therefore, it can reduce surface roughness. Firstly, titanium alloy powder is used to print the porous structure of the simulated trabecular bone with a metal 3D printer. After printing, heat treatment, removal of the supporting structure, and ultrasonic cleaning is carried out. Then, plasma polishing is performed, consisting of adding a polishing electrolyte with the pH set to 5.7, preheating the machine to 101.6 &#176;C, fixing the workpiece on the polishing fixture, and setting the voltage (313 V), current (59 A), and polishing time (3 min). After polishing, the surface of the porous titanium alloy workpiece is analyzed by a confocal microscope, and the surface roughness is measured. Scanning electron microscopy is used to characterize the surface condition of porous titanium. The results show that the surface roughness of the whole porous titanium alloy workpiece changed from Ra (average roughness) = 126.9 &#181;m to Ra = 56.28 &#181;m, and the surface roughness of the trabecular structure changed from Ra = 42.61 &#181;m to Ra = 26.25 &#181;m. Meanwhile, semi-molten powders and ablative oxide layers are removed, and surface quality is improved.

Plasma polishing is a promising surface processing technology, especially suitable for 3D printing of porous titanium alloy workpieces. It can remove semi-molten powders and ablative oxide layers, thereby effectively reducing surface roughness and improving surface quality.

Porous titanium alloy implants with simulated trabecular bone fabricated by 3D printing technology have broad prospects. However, due to the fact that ...