1 Configuration de champs stériles <ol><li> Don tenue correcte y compris chapeau et masque. Porter des lunettes de protection lorsque dans la salle de traitement. </li><li> Préparer la zone de traitement. Lors de l&#39;utilisation d&#39;une chambre de traitement, de maintenir un fonctionnement continu du ventilateur pour créer une pression positive dans la chambre. </li><li> Rassemblez toutes les fournitures. Vérifiez les dates d&#39;expiration, intégrité de l&#39;emballage, et l&#39;indicateur de stérilisation. </li><li> Se laver les mains et enfiler des gants non stériles. </li><li> Ouvrez les kits stériles pour établir un champ stérile. Lors de l&#39;utilisation d&#39;une salle de traitement, placer les kits sur la table et ouvrir de manière aseptique les enveloppements. Ne pas utiliser les extérieurs 1 ½ pouces de l&#39;enveloppe dans le cadre du champ stérile car ce segment est considéré comme non stérile. </li><li> En utilisant une technique aseptique, ouverte et déposer des éléments stériles sur champ stérile sauf si déjà partie de la meute premade. </li><li> Déplacez microscope afin qu&#39;il soit au-dessus du champ stérile, allumer la source de lumière de microscope, et ajuster oculaires comme nécessaire. </li><li> Obtain tissu cornéen à décaper (dans les milieux de la conservation) et place à côté de la zone de traitement stérile prêt. Desserrer le bouchon de chambre d&#39;observation et laissez-le reposer sur le dessus de la visualisation base de la chambre sans filets en prise. Jeter les gants non stériles. </li><li> Ouvrir une paire de gants stériles et une blouse stérile avec une serviette. </li><li> Effectuer le lavage chirurgical. Porter une blouse stérile, puis des gants stériles. </li><li> Boîtes d&#39;instruments ouverts de sorte que toutes les fournitures sont accessibles. Ouvrir l&#39;humidité du drap imperméable à créer la zone de travail. </li><li> Fixer l&#39;aiguille à une seringue de 5 ml. L&#39;utilisation d&#39;une pince hémostatique, préparer l&#39;aiguille 30 G en plaçant une courbure de 1 mm à partir du biseau, et un autre pli de 1 mm à partir de la base (pour former une forme en &quot;S&quot;). </li><li> Monter la seringue en verre pour la coloration au bleu trypan en plaçant le piston dans la seringue et le doigt de serrage sur le piston. Fixez la canule. </li><li> Fixer la canule du flacon de solution saline équilibrée (BSS). </li><li> Séparer le poinçon de trépan à partir du bloc de videet mettre de côté. Centrer le bloc de vide à l&#39;intérieur du champ de vision du microscope. </li><li> Apportez le bloc de vide au point en ajustant les réglages du microscope. </li></ol> 2 Procédure pour la préparation de tissu du donneur <ol><li> Soulevez le capot de chambre de visualisation utilisant carré de feuille comme un obstacle. Avec l&#39;autre main et l&#39;aide de pinces, saisir délicatement cornée par sclérotique jante pour enlever la cornée. Replacez le couvercle de la chambre de visualisation. </li><li> Enfoncez complètement la seringue d&#39;aspiration, puis placez côté de l&#39;épithélium de la cornée sur le bloc de vide et de veiller à ce qu&#39;il soit centré. (Figure 1) </li><li> Bague d&#39;assise légèrement inférieure sur le bloc de vide en utilisant les messages de guidage. Engager vide lentement en libérant le piston de la seringue d&#39;aspiration. Retirer la bague de siège et mettre de côté. (Figure 2). </li><li> Effectuez une trépanation partielle de marquer par l&#39;intermédiaire de la membrane de Descemet. </li><li> Réglez microscope zoom et mise au point pour que le tissu est bien visualisée. </li><li&gt; Inclinez le bloc de vide et d&#39;utiliser une lance d&#39;écouvillon stérile placé au limbe pour éliminer le milieu excès. (Figure 3) </li><li> Placez suffisamment de tache au limbe pour colorer le bord de la membrane de Descemet marqué. Laisser la tache de rester sur l&#39;endothélium de 60 à 90 sec. (Figure 4) </li><li> Retirer tache: <ol><li> Inclinez le bloc de vide à verser la tache de la cornée et sur de la gaze. </li><li> Utilisez les lances chirurgicales pour enlever l&#39;excès de colorant de la zone limbique de la cornée, en prenant soin de ne pas toucher l&#39;endothélium. (Figure 5) </li></ol></li><li> Utilisez quelques gouttes de BSS pour rincer la cornée de solution de coloration, et des lances d&#39;écouvillons stériles à enlever l&#39;excès de BSS. (Figure 6) </li><li> Placer 1-2 gouttes de BSS sur la jante de la sclérotique pour empêcher le tissu de séchage. Répéter au besoin tout au long de la procédure. </li><li> Effectuer dissection partielle de la membrane de Descemet: <ol><li> En commençant là où le tuyau se connecters au bloc de vide, en utilisant une pince ouverte, placez un bout à l&#39;orée de la marque de pointage et de la membrane de Descemet doucement séparé et l&#39;endothélium loin du stroma. (Figure 7). </li><li> La membrane et l&#39;endothélium de Descemet séparée pas plus de 1 mm du bord marqué et continuer à 360 ° autour de dissection. (Figure 8). </li><li> Remarque emplacement des micro-déchirures en plaçant un point sur le bloc de vide avec le marqueur de la peau. REMARQUE: Si le trépan ne pénètre pas complètement à travers la membrane de Descemet, utilisez le bord biseauté de la prêts aiguille 30 G pour compléter le score par l&#39;intermédiaire de la membrane de Descemet le cas échéant, suivie d&#39;une deuxième application de la coloration au besoin. Si l&#39;adhérence de la membrane de Descemet entrave la dissection partielle, retirer l&#39;endothélium dehors de la zone trephinated au besoin. </li></ol></li><li> Utilisez une pince pour enlever les balises endothéliales qui se chevauchent la marque de pointage. </li> &lt;li&gt; Pensez à l&#39;emplacement de précédemment marqués micro larmes et faire tourner le bloc de vide, de sorte que le plus grand est à 06 heures. Cela deviendra la charnière de la trappe. </li><li> Utilisation de la pince, saisir la membrane de Descemet à 12 heures. Séparer doucement la membrane de Descemet du stroma par pelage vers la charnière. Créer la charnière par l&#39;arrêt de la séparation de 2 mm de la marque de pointage. REMARQUE: les bords périphériques de volets commenceront à défiler lors de la séparation. (Figure 9). </li><li> Déposer délicatement le rabat en place sur le stroma. Utilisez SRS et écouvillon lances à unscroll l&#39;endothélium et le retourner à sa position initiale. (Figure 10A-C) </li><li> Retirer liquide résiduel de la membrane entre stroma et de Descemet avec des lances d&#39;écouvillons stériles de sorte que le volet reste en position. (Figure 11) </li><li> Utilisez des lances d&#39;écouvillons stériles pour absorber l&#39;excès d&#39;humidité de la sclérotique près de la charnière. Utilisez le marqueur de la peau de tirer unn pointe de flèche sur le bord de la sclérotique pointant vers le centre de la charnière, enlever tout excès d&#39;encre en utilisant un écouvillon stérile lance. (Figure 12) </li><li> Relâcher le vide en appuyant sur le piston de la seringue reliée au bloc d&#39;aspiration. Alors que le vide est libéré, utiliser une pince pour retirer la cornée à partir du bloc d&#39;aspiration. </li><li> Soulevez le capot de chambre de visualisation utilisant carré de feuille comme un obstacle. Placez la cornée dans la chambre d&#39;observation, côté endothéliale, et replacez le couvercle de la chambre de visualisation. </li><li> Répétez la procédure avec étapes compagnon cornée, le cas échéant. Utiliser de la gaze pour nettoyer le bloc de vide avant de traiter le second tissu. </li><li> Serrez le couvercle (s) de la chambre de visualisation et enlever les tissus de la zone de traitement. </li><li> Décomposer le champ stérile en disposant d&#39;éléments selon le plan de gestion des déchets biologiques dangereux. Enlever les gants contaminés et robe. Se laver les mains et enfiler des gants non stériles. </li><li> Effectuer l&#39;évaluation post-coupe de la lampe à fente et la microscopie spéculaire de la cornée (s)et consigner les résultats. </li></ol>

<ol>
	<li>Fernandez, M., Afshari, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endothelial+Keratoplasty:+From+DLEK+to+DMEK.">Endothelial Keratoplasty: From DLEK to DMEK.</a> Middle East African Journal of Ophthalmology. 17 (1), 5-8 (2010).</li><li>Kruse, F., 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=A+Stepwise+Approach+to+Donor+Preparation+and+Insertion+Increases+Safety+and+Outcome+of+Descemet+Membrane+Endothelial+Keratoplasty.">A Stepwise Approach to Donor Preparation and Insertion Increases Safety and Outcome of Descemet Membrane Endothelial Keratoplasty.</a> Cornea. 30 (5), 580-587 (2011).</li><li>Dapena, I., Moutsouris, K., Droutsas, K., Ham, L., van Dijk, K., Melles, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standardized+'No-Touch'+Technique+for+Descemet+Membrane+Endothelial+Keratoplasty.">Standardized 'No-Touch' Technique for Descemet Membrane Endothelial Keratoplasty.</a> Archives of Ophthalmology. 129, 88-94 (2011).</li><li>Tourtas, T., Laaser, K., Bachmann, B., Cursiefen, C., Kruse, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Descemet+Membrane+Endothelial+Keratoplasty+versus+Descemet+Stripping+Automated+Endothelial+Keratoplasty.">Descemet Membrane Endothelial Keratoplasty versus Descemet Stripping Automated Endothelial Keratoplasty.</a> American Journal of Ophthalmology. 153 (6), 1082-1090 (2012).</li><li>Guerra, F., Anshu, A., Price, M., Price, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endothelial+Keratoplasty:+fellow+eyes+comparison+of+Descemet+stripping+automated+endothelial+keratoplasty+and+Descemet+membrane+endothelial+keratoplasty.">Endothelial Keratoplasty: fellow eyes comparison of Descemet stripping automated endothelial keratoplasty and Descemet membrane endothelial keratoplasty.</a> Cornea. 30 (12), 1382-1386 (2011).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> 2012 Eye Banking Statistical Report: Surgical Use and Indications for Corneal Transplant Statistical Report Analysis. , (2012).</li><li>Price, M., Price, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Descemet's+stripping+endothelial+keratoplasty.">Descemet's stripping endothelial keratoplasty.</a> Current Opinion Ophthalmology. 18 (4), 290-294 (2007).</li><li>Woodward, M., Titus, M., Mavin, K., Shtein, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corneal+Donor+Tissue+Preparation+for+Endothelial+Keratoplasty.">Corneal Donor Tissue Preparation for Endothelial Keratoplasty.</a> Journal of Visualized Experiments. (64), e3847 (2012).</li><li>Price, M., Price, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Descemet's+membrane+endothelial+keratoplasty+surgery:+update+on+the+evidence+and+hurdles+to+acceptance.">Descemet's membrane endothelial keratoplasty surgery: update on the evidence and hurdles to acceptance.</a> Current Opinion Ophthalmology. 24 (4), 329-335 (2013).</li><li>Venzano, D., Pagani, P., Randazzo, N., Cabiddu, F., Traverrso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Descemet+Membrane+air-bubble+separation+in+donor+cornea.">Descemet Membrane air-bubble separation in donor cornea.</a> Journal of Cataract and Refractive Surgery. 36 (12), 2022-2027 (2010).</li><li>Price, F., Price, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> DSEK: What you need to know about endothelial keratoplasty. , (2009).</li><li>Studeny, P., Sivekova, D., Lieheova, K., Vokrojova, M., Kuchynka, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hybrid+technique+of+lamellar+keratoplasty+(DMEK-S).">Hybrid technique of lamellar keratoplasty (DMEK-S).</a> Journal of Ophthalmology. 2013, 2013.254383 (2013).</li><li>Muraine, M., Gueudry, J., He, Z., Piselli, S., Lefevre, S., Toubeau, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+technique+for+the+preparation+of+corneal+grafts+for+Descemet+membrane+endothelial+keratoplasty.">Novel technique for the preparation of corneal grafts for Descemet membrane endothelial keratoplasty.</a> American Journal of Ophthalmology. 156 (5), 851-859 (2013).</li><li>Lie, J. T., Birbal, R., Ham, L., van der Wees, J., Melles, G. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Donor+tissue+preparation+for+Descemet+membrane+endothelial+keratoplasty.">Donor tissue preparation for Descemet membrane endothelial keratoplasty.</a> Journal of Cataract Refractive Surgery. 34 (9), 1578-1583 (2008).</li><li>Kruse, F. E., Laaser, K., Cursiefen, C., Heindl, L. M., Schlotzer-Schrehardt, U., Riss, S., Bachmann, B. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+stepwise+approach+to+donor+preparation+and+insertion+increases+safety+and+outcome+of+Descemet+membrane+endothelial+keratoplasty.">A stepwise approach to donor preparation and insertion increases safety and outcome of Descemet membrane endothelial keratoplasty.</a> Cornea. 30 (5), 580-587 (2011).</li><li>Rudolph, M., Kaaser, L., Bachmann, B., Cursiefen, C., Epstein, D., Kruse, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corneal+higher-order+aberrations+after+Descemet&#8217;s+membrane+endothelial+keratoplasty.">Corneal higher-order aberrations after Descemet&#8217;s membrane endothelial keratoplasty.</a> Ophthalmology. 119 (3), 528-535 (2012).</li><li>Price, F., Price, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolution+of+endothelial+keratoplasty.">Evolution of endothelial keratoplasty.</a> Cornea. 32, 28-32 (2013).</li><li>Dapena, I., Dapena, L., Dirisamer, M., Ham, L., Melles, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+acuity+and+endothelial+cell+density+following+Descemet+membrane+endothelial+keratoplasty+(DMEK).">Visual acuity and endothelial cell density following Descemet membrane endothelial keratoplasty (DMEK).</a> Arch Soc Esp Oftalmol. 86 (12), 395-401 (2011).</li></ol>

Hassan Tausif et le Dr Navasuja Chandrasekaran n&#39;ont rien à divulguer. Drs. Mian, Shtein, et Woodward sont les directeurs médicaux de la Banque Michigan yeux. M. Mavin, M. Titus, et Mme Johnson sont des employés de Midwest banques d&#39;yeux.

La couche de cellules endothéliales de la cornée joue un rôle critique dans le maintien de la clarté de la cornée par déshydratation. Maladies des cellules endothéliales peuvent entraîner une déficience visuelle importante. DMEK vise à remplacer les cellules endothéliales malades avec un greffon du donneur constitué de membrane et endothéliale couche de cellules de Descemet. la préparation des tissus du donneur avec un DM intact et nombre de cellules endothéliales adéquate sont essentiels à la survie du...

Endothéliale Keratoplasty (EK) a rapidement remplacé kératoplastie (PKP) que la procédure de choix pour le traitement de maladies endothéliales qui représentent plus de 50% de toutes les transplantations effectuées aux États-Unis en 2012 6. PKP est limitée par la réhabilitation visuelle prolongée à haute astigmatisme et l&#39;instabilité de réfraction, la perte de l&#39;intégrité du globe et les complications liées à la suture. Procédures d&#39;EK de première génération, y compris en profondeur lamellaire endothéliale Keratoplasty (DLEK) impliqués dissection manuelle de stroma cornéen avec la transplantation de l&#39;épaisseur des tissus du donneur partielle. Ces procédures ont réussi à transplanter des tissus de l&#39;endothélium des bailleurs de fonds, tout en maintenant une surface de la cornée intacte mais étaient techniquement difficile et conduit à limiter la meilleure acuité visuelle corrigée en raison de l&#39;interface lamellaire de la cornée irrégulière 1. La procédure d&#39;EK de choix actuel est Décapage endothéliale Keratoplasty de Descemet (DSEK) qui offre clar cornéelité avec une récupération plus rapide de la vision, minimise l&#39;erreur de réfraction postopératoire et l&#39;astigmatisme, et diminue le risque de déhiscence de la plaie traumatique tout en maintenant la surface de la cornée 7. Cette procédure implique l&#39;ablation de la membrane de Descemet et de l&#39;endothélium malade et le remplacement partiel de donneur d&#39;épaisseur du tissu de la cornée comprenant une nouvelle couche de cellules endothéliales. La cornée du donneur est disséqué avec un microkératome pour préparer le tissu transplanté est postérieure 8. Préparation du tissu du donneur par les oculaires banques a contribué à la croissance rapide et, sans doute, le succès de cette procédure. L&#39;augmentation de 16 fois près de procédures DSEK aux États-Unis entre 2005 et 2012 correspond à près de la moitié du tissu en cours de préparation par les oculaires banques 6. Bien DSEK peut améliorer l&#39;acuité visuelle de 20/40 ou mieux, la plupart des patients n&#39;atteignent pas 20/20 vision grâce à l&#39;interface du stroma brume et la lumière accruedisperser de l&#39;ajout de donneur stroma tissu 7. La technique chirurgicale EK a progressé à membrane endothéliale Keratoplasty de Descemet (DMEK) qui implique la transplantation de la membrane (DM) et l&#39;endothélium de Descemet seul bailleur de fonds. Cette procédure a une plus grande proportion de patients qui atteignent 20/20 vision, la récupération visuelle plus rapide, et un moindre risque de rejet endothélial 9. Cependant, la préparation de tissu du donneur est plus difficile en raison des dimensions plus fines greffés.

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			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:268px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">VisionBlue&#160;</td>
			<td style="width:268px;">D.O.R.C., Zuiland, The Netherlands</td>
			<td style="width:119px;">NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Barron vacuum punch</td>
			<td style="width:268px;">Katena, Denville, New Jersey</td>
			<td style="width:119px;">K20-2112</td>
			<td></td>
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corneal donor tissue preparation for descemet's membrane endothelial keratoplasty

Membrane Endothelial Keratoplasty de Descemet (DMEK) est une forme de greffe de cornée dans laquelle seule une couche de cellules unique, l&#39;endothélium cornéen, avec sa membrane basale (la membrane de Descemet) est introduit sur ​​postérieure du stroma du destinataire 3. Contrairement à dénuder automatique endothéliale Keratoplasty de Descemet (DSAEK), où plus stroma du donneur est introduit, aucune interface anormal stroma-à-stroma est créé. En conséquence, l&#39;anatomie naturelle de la cornée est conservée autant que possible permettant d&#39;améliorer le temps de récupération de l&#39;acuité visuelle et 4. Endothéliale Keratoplasty (EK) est la procédure de choix pour le traitement de la dysfonction endothéliale. Les avantages de EK comprennent la récupération rapide de la vision, de la préservation de l&#39;intégrité oculaire et le changement de réfraction minime en raison de l&#39;utilisation d&#39;une petite incision périphérique 1. DSAEK utilise le tissu du donneur préparé avec stroma d&#39;épaisseur partielle et l&#39;endothélium. Le succ rapideess et l&#39;utilisation de cette procédure peut être attribuée à la disponibilité de l&#39;œil-banque de tissus prédécoupés préparé. Les avantages de la préparation yeux banque de tissus de donneurs comprennent l&#39;élimination de la nécessité d&#39;un équipement spécialisé dans la salle d&#39;opération et la disponibilité des back up de tissu du donneur en cas de perforation de tissu lors de la préparation. En outre, la préparation du volume élevé de tissu du donneur par des techniciens œil bancaires peut fournir une meilleure qualité de tissu du donneur. DSAEK peut avoir limité la meilleure acuité visuelle corrigée en raison de la création d&#39;une interface de stroma entre le donateur et bénéficiaire cornée. L&#39;élimination de cette interface avec la transplantation de la membrane et de l&#39;endothélium seul bailleur de fonds de Descemet dans DMEK peut améliorer les résultats visuels et de réduire les complications après EK 5. Similaire à DSAEK, le succès à long terme et l&#39;acceptation de DMEK dépend de la facilité de la disponibilité de prédécoupée, eye-banque, a préparé le tissu du donneur. Nous présentons ici une approche par étapes pour la préparation de tissu du donneur qui peuvent réduire certaines barriteurs oculaires banques font face dans la fourniture de greffons DMEK.

Séparation adéquate des DM et de l&#39;endothélium de stroma est essentiel dans la préparation des tissus prédécoupés pour DMEK. Cinquante cornées de donneurs avec un âge moyen de 65 ± 6 ans (extrêmes: 55-75), mort en temps de traitement de 5,9 ± 2,3 jours (extrêmes 1-10) et de la densité des cellules endothéliales (DPE) de 2616 ± 321 cellules / mm 2 ( gamme 2,049-3,247) ont été utilisés pour évaluer la faisabilité et la reproductibilité de la technique de préparation chirurgicale par d...

Watch this Scientific Journal Video about Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty at JoVE.com

Corneal Donor Tissue Preparation for Descemet&#039;s Membrane Endothelial Keratoplasty

Kératoplastie endothéliale est une technique chirurgicale en constante évolution que les avancées se traduisent par la transplantation de greffons les plus fines avec chaque succession 1. Ici, nous présentons une technique de dissection du tissu à commande manuelle pour permettre une séparation sûre et reproductible de l&#39;endothélium et les membranes de Descemet de donateurs boutons cornéosclérale pour la transplantation 2.

Préparation de tissu du donneur de cornée pour membrane endothéliale Keratoplasty de Descemet

Descemet&#8217;s Membrane Endothelial Keratoplasty (DMEK) is a form of corneal transplantation in which only a single cell layer, the corneal endothelium, ...

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Medicine

Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty

15.2K vues.  University of Michigan.  Kératoplastie endothéliale est une technique chirurgicale en constante évolution que les avancées se traduisent par la transplantation de greffons les plus fines avec chaque succession 1. Ici, nous présentons une technique de dissection du tissu à commande manuelle pour permettre une séparation sûre et reproductible de l'endothélium et les membranes de Descemet de donateurs boutons cornéosclérale pour la transplantation 2. 

Vidéo: Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty

Single Port Donor Nephrectomy

In 2007, Rane presented the first single port nephrectomy for a small non-functioning kidney at the World Congress of Endourology. Since that time, the use of single port surgery for nephrectomy has expanded to include donor nephrectomy. Over the next two years the technique was adopted for many others types of nephrectomies to include donor nephrectomy. We present our technique for single port donor nephrectomy using the Gelpoint device. We have successfully performed this surgery in over 100 patients and add this experience to our experience of over 1000 laparoscopic nephrectomies. With the proper equipment and technique, single port donor nephrectomy can be performed safely and effectively in the majority of live donors. We have found that our operative times and most importantly our transplant outcomes have not changed significantly with the adoption of the single port donor nephrectomy. We believe that single port donor nephrectomy represents a step forward in the care of living donors.

Single port laparoscopic surgery is changing the standard of care in surgical care like nothing since the laparoscopic technique was introduced 20 years ago. We present out technique of single port donor nephrectomy using the Gelpoint device. We have successfully performed this surgery in 100 patients.

Simple néphrectomie Port

In 2007, Rane presented the first single port nephrectomy for a small non-functioning kidney at the World Congress of Endourology.  Since that time, the ...

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Corneal Donor Tissue Preparation for Endothelial Keratoplasty

Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes1,2. Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK), transplanting only the posterior corneal stroma, Descemet's membrane, and endothelium, has dramatically changed treatment of corneal endothelial disease. DSEK is performed through a smaller incision; this technique avoids 'open sky' surgery with its risk of hemorrhage or expulsion, decreases the incidence of postoperative wound dehiscence, reduces unpredictable refractive outcomes, and may decrease the rate of transplant rejection3-6.
Initially, cornea donor posterior lamellar dissection for DSEK was performed manually1 resulting in variable graft thickness and damage to the delicate corneal endothelial tissue during tissue processing. Automated lamellar dissection (Descemet's stripping automated endothelial keratoplasty, DSAEK) was developed to address these issues. Automated dissection utilizes the same technology as LASIK corneal flap creation with a mechanical microkeratome blade that helps to create uniform and thin tissue grafts for DSAEK surgery with minimal corneal endothelial cell loss in tissue processing.
Eye banks have been providing full thickness corneas for surgical transplantation for many years. In 2006, eye banks began to develop methodologies for supplying precut corneal tissue for endothelial keratoplasty. With the input of corneal surgeons, eye banks have developed thorough protocols to safely and effectively prepare posterior lamellar tissue for DSAEK surgery. This can be performed preoperatively at the eye bank. Research shows no significant difference in terms of the quality of the tissue7 or patient outcomes8,9 using eye bank precut tissue versus surgeon-prepared tissue for DSAEK surgery. For most corneal surgeons, the availability of precut DSAEK corneal tissue saves time and money10, and reduces the stress of performing the donor corneal dissection in the operating room. In part because of the ability of the eye banks to provide high quality posterior lamellar corneal in a timely manner, DSAEK has become the standard of care for surgical management of corneal endothelial disease.
The procedure that we are describing is the preparation of the posterior lamellar cornea at the eye bank for transplantation in DSAEK surgery (Figure 1).

Endothelial corneal transplantation is a surgical technique for treatment of posterior corneal diseases. Mechanical microkeratome dissection to prepare tissue results in thinner, more symmetric grafts with less endothelial cell loss and improved outcomes. Dissections can be performed at the eye bank prior to corneal transplantation surgery.

Cornée Préparation tissu du donneur pour kératoplastie endothéliale

Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes1,2. Since its inception, traditional full ...

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene and cell therapies are highly promising alternative approaches for CVD treatment. However, the broad clinical application of gene therapy is greatly limited by the lack of suitable gene delivery systems. The development of appropriate gene delivery vectors can provide a solution to current challenges in cell therapy. In particular, existing drawbacks, such as limited efficiency and low cell retention in the injured organ, could be overcome by appropriate cell engineering (i.e., genetic) prior to transplantation. The presented protocol describes the efficient and safe transient modification of endothelial cells using a polyethyleneimine superparamagnetic magnetic nanoparticle (PEI/MNP)-based delivery vector. Also, the algorithm and methods for cell characterization are defined. The successful intracellular delivery of microRNA (miR) into human umbilical vein endothelial cells (HUVECs) has been achieved without affecting cell viability, functionality, or intercellular communication. Moreover, this approach was proven to cause a strong functional effect in introduced exogenous miR. Importantly, the application of this MNP-based vector ensures cell magnetization, with accompanying possibilities of magnetic targeting and non-invasive MRI tracing. This may provide a basis for magnetically guided, genetically engineered cell therapeutics that can be monitored non-invasively with MRI.

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

This manuscript describes the efficient, non-viral delivery of miR to endothelial cells by a PEI/MNP vector and their magnetization. Thus, in addition to genetic modification, this approach allows for magnetic cell guidance and MRI detectability. The technique can be used to improve the characteristics of therapeutic cell products.

préparation et<em&gt; In vitro</em&gt; Caractérisation des aimanté miR-modifié cellules endothéliales

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene ...

Ex Vivo Corneal Organ Culture Model for Wound Healing Studies

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two dimensional (2D) and three dimensional (3D) culture has generated a wealth of information not only about corneal biology but also about wound healing, myofibroblast biology, and scarring in general. The goal of the protocol is an assay system for quantifying myofibroblast development, which characterizes scarring. We demonstrate a corneal organ culture ex vivo model using pig eyes. In this anterior keratectomy wound, corneas still in the globe are wounded with a circular blade called a trephine. A plug of approximately 1/3 of the anterior cornea is removed including the epithelium, the basement membrane, and the anterior part of the stroma. After wounding, corneas are cut from the globe, mounted on a collagen/agar base, and cultured for two weeks in supplemented-serum free medium with stabilized vitamin C to augment cell proliferation and extracellular matrix secretion by resident fibroblasts. Activation of myofibroblasts in the anterior stroma is evident in the healed cornea. This model can be used to assay wound closure, the development of myofibroblasts and fibrotic markers, and for toxicology studies. In addition, the effects of small molecule inhibitors as well as lipid-mediated siRNA transfection for gene knockdown can be tested in this system.

A protocol for an ex vivo corneal organ culture model useful for wound healing studies is described. This model system can be used to assess the effects of agents to promote regenerative healing or drug toxicity in an organized 3D multicellular environment.

Ex Vivo, modèle de Culture d’organes cornéenne pour la cicatrisation des études

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two ...

A Porcine Corneal Endothelial Organ Culture Model Using Split Corneal Buttons

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for experimental investigations as they are normally needed for transplantation. Endothelial cell cultures often do not translate well to in vivo situations. Due to the biostructural characteristics of non-human corneas, stromal swelling during cultivation induces substantial corneal endothelial cell loss, which makes it difficult to perform cultivation for an extended period of time. Deswelling agents such as dextran are used to counteract this response. However, they also cause significant endothelial cell loss. Therefore, an ex vivo organ culture model not requiring deswelling agents was established. Pig eyes from a local slaughterhouse were used to prepare split corneal buttons. After partial corneal trephination, the outer layers of the cornea (epithelium, bowman layer, parts of the stroma) were removed. This significantly reduces corneal endothelial cell loss induced by massive stromal swelling and Descemet&#39;s membrane folding throughout longer cultivation periods and improves general preservation of the endothelial cell layer. Subsequent complete corneal trephination was followed by the removal of the split corneal button from the remaining eye bulb and cultivation. Endothelial cell density was assessed at follow-up times of up to 15 days after preparation (i.e., days 1, 8, 15) using light microscopy. The preparation technique used allows a better preservation of the endothelial cell layer enabled by less stromal tissue swelling, which results in slow and linear decline rates in split corneal buttons comparable to human donor corneas. As this standardized organo-typically cultivated research model for the first time allows a stable cultivation for at least two weeks, it is a valuable alternative to human donor corneas for future investigations of various external factors with regards to their effects on the corneal endothelium.

Here, a step-by-step protocol for the preparation and cultivation of porcine split corneal buttons is presented. As this organo-typically cultivated organ culture model shows cell death rates within 15 days, comparable to human donor corneas, it represents the first model allowing long-term cultivation of non-human corneas without adding toxic dextran.

Un modèle de culture d'orgue endothéliale de porc cornée utilisant des boutons cornéens fendus

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for ...

Development of a Noninvasive, Laser-Assisted Experimental Model of Corneal Endothelial Cell Loss

Nd:YAG lasers have been used to perform noninvasive intraocular surgery, such as capsulotomy for several decades now. The incisive effect relies on the optical breakdown at the laser focus. Acoustic shock waves and cavitation bubbles are generated, causing tissue rupture. Bubble sizes and pressure amplitudes vary with pulse energy and position of the focal point. In this study, enucleated porcine eyes were positioned in front of a commercially available Nd:YAG laser. Variable pulse energies as well as different positions of the focal spots posterior to the cornea were tested. Resulting lesions were evaluated by two-photon microscopy and histology to determine the best parameters for an exclusive detachment of corneal endothelial cells (CEC) with minimum collateral damage. The advantages of this method are the precise ablation of CEC, reduced collateral damage, and above all, the non-contact treatment.

Here, we present a protocol to detach corneal endothelial cells (CEC) from Descemet&#8217;s membrane (DM) using a neodymium:YAG (Nd:YAG) laser as an ex vivo disease model for bullous keratopathy (BK).

Développement d’un modèle expérimental non invasif assisté au laser de la perte de cellules endothéliales cornéennes

Nd:YAG lasers have been used to perform noninvasive intraocular surgery, such as capsulotomy for several decades now. The incisive effect relies on the ...

An Epithelial Abrasion Model for Studying Corneal Wound Healing

The cornea is critical for vision, accounting for about two-thirds of the refractive power of the eye. Crucial to the role of the cornea in vision is its transparency. However, due to its external position, the cornea is highly susceptible to a wide variety of injuries that can lead to the loss of corneal transparency and eventual blindness. Efficient corneal wound healing in response to these injuries is pivotal for maintaining corneal homeostasis and preservation of corneal transparency and refractive capabilities. In events of compromised corneal wound healing, the cornea becomes vulnerable to infections, ulcerations, and scarring. Given the fundamental importance of corneal wound healing to the preservation of corneal transparency and vision, a better understanding of the normal corneal wound healing process is a prerequisite to understanding impaired corneal wound healing associated with infection and disease. Toward this goal, murine models of corneal wounding have proven useful in furthering our understanding of the corneal wound healing mechanisms operating under normal physiological conditions. Here, a protocol for creating a central corneal epithelial abrasion in mouse using a trephine and a blunt golf club spud is described. In this model, a 2 mm diameter circular trephine, centered over the cornea, is used to demarcate the wound area. The golf club spud is used with care to debride the epithelium and create a circular wound without damaging the corneal epithelial basement membrane. The resulting inflammatory response proceeds as a well-characterized cascade of cellular and molecular events that are critical for efficient wound healing. This simple corneal wound healing model is highly reproducible and well-published and is now being used to evaluate compromised corneal wound healing in the context of disease.

Here, a protocol for creating a central corneal epithelial abrasion wound in the mouse using a trephine and a blunt golf club spud is described. This corneal wound healing model is highly reproducible and is now being used to evaluate compromised corneal wound healing in the context of diseases.

Un modèle d’abrasion épithéliale pour étudier la cicatrisation des plaies cornéennes

The cornea is critical for vision, accounting for about two-thirds of the refractive power of the eye. Crucial to the role of the cornea in vision is its ...

A Porcine Heterotopic Heart Transplantation Protocol for Delivery of Therapeutics to a Cardiac Allograft

Cardiac transplantation is the gold standard treatment for end-stage heart failure. However, it remains limited by the number of available donor hearts and complications such as primary graft dysfunction and graft rejection. The recent clinical use of an ex vivo perfusion device in cardiac transplantation introduces a unique opportunity for treating cardiac allografts with therapeutic interventions to improve function and avoid deleterious recipient responses. Establishing a translational, large-animal model for therapeutic delivery to the entire allograft is essential for testing novel therapeutic approaches in cardiac transplantation. The porcine, heterotopic heart transplantation model in the intraabdominal position serves as an excellent model for assessing the effects of novel interventions and the immunopathology of graft rejection. This model additionally offers long-term survival for the pig, given that the graft is not required to maintain the recipient's circulation. The aim of this protocol is to provide a reproducible and robust approach for achieving ex vivo delivery of a therapeutic to the entire cardiac allograft prior to transplantation and provide technical details to perform a survival heterotopic transplant of the ex vivo perfused heart.

We present a protocol for utilizing a normothermic ex vivo sanguinous perfusion system for the delivery of therapeutics to an entire cardiac allograft in a porcine heterotopic heart transplant model.

Protocole de transplantation cardiaque hétérotopique porcine pour l’administration de produits thérapeutiques à une allogreffe cardiaque

Cardiac transplantation is the gold standard treatment for end-stage heart failure. However, it remains limited by the number of available donor hearts ...

A Human Corneal Organ Culture Model of Descemet's Stripping Only with Accelerated Healing Stimulated by Engineered Fibroblast Growth Factor 1

Fuchs Endothelial Corneal Dystrophy (FECD) results from dysfunctional corneal endothelial cells (CECs) and is currently treated by transplantation of the whole cornea or Descemet's membrane. Recent developments in ocular surgery have established Descemet's Stripping Only (DSO), a surgical technique in which a central circle of guttae-dense Descemet's membrane is removed to allow for the migration of CECs onto the smooth stroma, restoring function and vision to the cornea. While this potential treatment option is of high interest in the field of ophthalmic research, no successful ex vivo models of DSO have been established and clinical data is limited. This work presents a novel wound-healing model simulating DSO in human donor corneas. Using this approach to evaluate the efficacy of the human engineered FGF1 (NM141), we found that treatment accelerated healing via stimulation of migration and proliferation of CECs. This finding was confirmed in 11 pairs of human corneas with signs of dystrophy reported by the eye banks in order to verify that these results can be replicated in patients with Fuchs' Dystrophy, as the target population of the DSO procedure.

A Human Corneal Organ Culture Model of Descemet&#039;s Stripping Only with Accelerated Healing Stimulated by Engineered Fibroblast Growth Factor 1

Descemet's Stripping Only is an experimental procedure wherein patients with central corneal guttae resulting from Fuchs Endothelial Corneal Dystrophy have Descemet's membrane stripped for peripheral cells to regenerate the endothelial layer. We present novel methodology simulating DSO in dystrophic human corneas ex vivo with accelerated healing stimulated by eFGF1 (NM141).

Un modèle de culture d’organes cornéens humains du décapage de Descemet uniquement avec une guérison accélérée stimulée par le facteur de croissance des fibroblastes 1

Fuchs Endothelial Corneal Dystrophy (FECD) results from dysfunctional corneal endothelial cells (CECs) and is currently treated by transplantation of the ...

Preparation of Human Myocardial Tissue for Long-Term Cultivation

Cardiomyocyte cultivation has seen a vast number of developments, ranging from two-dimensional (2D) cell cultivation to iPSC derived organoids. In 2019, an ex vivo way to cultivate myocardial slices obtained from human heart samples was demonstrated, while approaching in vivo condition of myocardial contraction. These samples originate mostly from heart transplantations or left-ventricular assist device placements. Using a vibratome and a specially developed cultivation system, 300 &#181;m thick slices are placed between a fixed and a spring wire, allowing for stable and reproducible cultivation for several weeks. During cultivation, the slices are continuously stimulated according to individual settings. Contractions can be displayed and recorded in real-time, and pharmacological agents can be readily applied. User-defined stimulation protocols can be scheduled and performed to assess vital contraction parameters like post-pause-potentiation, stimulation threshold, force-frequency relation, and refractory period. Furthermore, the system enables a variable pre- and afterload setting for a more physiological cultivation.
Here, we present a step-by-step guide on how to generate a successful long-term cultivation of human left ventricular myocardial slices, using a commercial biomimetic cultivation solution.

We present a protocol for ex vivo cultivation of human ventricular myocardial tissue. It allows for detailed analysis of contraction force and kinetics, as well as the application of pre- and afterload to mimic the in vivo physiological environment more closely.

Préparation de tissu myocardique humain pour la culture à long terme

Cardiomyocyte cultivation has seen a vast number of developments, ranging from two-dimensional (2D) cell cultivation to iPSC derived organoids. In 2019, ...