Questo lavoro è supportato in parte dal Comando del materiale di ricerca medica dell'esercito degli Stati Uniti sotto W81XWH-08-1-0503 e W81XWH-12-1-0066, dalle sovvenzioni AHA n. 0655441U e 15SDG25740015 e da NIH R21 HL081892, R21 HL130899, R21 HL089175, RC1 DK087365, R01 DK098526, R01 DK118964, R01 CA140338, R01 CA234428, da Lantheus Medical Imaging e da GE Healthcare, Oslo, Norvegia.

I comitati di revisione istituzionale della Thomas Jefferson University e dell'Ospedale dell'Università della Pennsylvania hanno approvato questo protocollo. Il protocollo è conforme all'Health Insurance Portability and Accountability Act. La Food and Drug Administration (FDA) degli Stati Uniti ha rilasciato un'approvazione per un nuovo farmaco sperimentale (IND # 124.465 a F. Forsberg) per questo protocollo. GE Healthcare (Oslo, Norvegia) ha fornito l'UCA utilizzato in questa ricerca (Sonazoid; Tabella 1). Il sonazoide non è approvato dalla FDA per alcuna applicazione clinica negli Stati Uniti, motivo per cui era necessario un IND. Altri UCA con approvazione FDA1 possono essere utilizzati off-label a discrezione del medico curante se ritenuti potenzialmente clinicamente utili.
NOTA: Il protocollo completo e il piano di analisi statistica sono disponibili all'indirizzo https:// clinicaltrials.gov/ct2/show/NCT02489045. Numero di registrazione della versione di prova: NCT # 02489045.
1. Preparazione del soggetto
<ol><li>Rivedere le allergie o le intolleranze ai farmaci note del soggetto, in particolare qualsiasi allergia nota all'UCA utilizzata.</li>
	<li>Escludere i soggetti con condizioni cardiopolmonari instabili o che sono generalmente instabili dal punto di vista medico.</li>
	<li>Mettere il soggetto su una barella in posizione supina.</li>
	<li>Posizionare una cannula di calibro 18 - 22 in una vena del braccio destro o sinistro del soggetto per l'infusione di UCA.</li>
	<li>Assicurarsi che i servizi di emergenza (ad esempio, un carrello per incidenti) siano disponibili all'interno dell'ospedale in caso di reazioni avverse acute. NOTA: GLI UCA sono molto sicuri con gravi reazioni di tipo anafilattoide riportate ad un tasso inferiore allo 0,01%. 20</li>
</ol>2. Preparazione UCA (specifica per Sonazoid)
<ol><li>Preparare tre (3) flaconcini con 48 μL di microbolle (6 ml) per ciascun soggetto riassumendo secondo le istruzioni del produttore. L'UCA viene fornito come polvere secca entro flaconcini sigillati da 10 ml. Lo spazio di testa dei flaconcini contiene perfluorobutano.<ol><li>Perforare il tappo del flaconcino di UCA con un chemiospike.</li>
		<li>Rimuovere il cappuccio protettivo dalla porta della siringa del chemospike e aggiungere 2 ml di acqua sterile.</li>
		<li>Con la siringa che rimane attaccata al chemiospike, agitare immediatamente il prodotto per 1 minuto per garantire un prodotto omogeneo.</li>
		<li>Aspirare il prodotto nella siringa e reiniettare nuovamente il prodotto nel flaconcino. Questo per evitare la diluizione del prodotto a causa del volume dello spazio morto nel chemiospike.</li>
		<li>Rimuovere la siringa dalla porta della siringa e ricollegare il cappuccio protettivo. La concentrazione dell'UCA ricostituito è di 8 μL di microbolle/ml.</li>
		<li>Ripetere la procedura di ricostituzione per gli altri 2 flaconcini.</li>
	</ol></li>
	<li>Utilizzare soluzione salina (soluzione allo 0,9% di NaCl) per riempire i tubi di collegamento prima di essere collegati a un rubinetto di arresto a 3 vie. Il rubinetto di arresto sarà quindi collegato al tubo di prolunga che conduce alla cannula.</li>
	<li>Aspirare tutti e tre (3) i flaconcini di UCA sospesi in una siringa da 10 mL, inserirla in una pompa a siringa allo stesso livello o sotto il paziente e collegarla direttamente al rubinetto.</li>
	<li>Dopo l'ecografia iniziale e dopo l'apertura del rubinetto, infondere la soluzione di NaCl ad una velocità di 120 ml/ora e co-infondere Sonazoid ad una velocità di 0,024 μL per kg di peso corporeo al minuto (velocità di infusione in sospensione di 0,18 ml/kg/ora). NOTA: Questa velocità di infusione è stata selezionata sulla base delle precedenti esperienze del nostro gruppo con infusione di Sonazoid in soggetti con ipertensione portale sottoposti a SHAPE13,14,21. L'esatta procedura di risospensione e il metodo di infusione variano a seconda dell'UCA utilizzato.</li>
</ol>3. Ecografia iniziale
<ol><li>Accendere uno scanner a ultrasuoni (ad esempio, Logiq E10, versione R2) e selezionare la sonda curvilinea C1-6-D.</li>
	<li>Selezionare un preset addominale sullo scanner a ultrasuoni e utilizzare un array curvi-lineare (in genere con una larghezza di banda di 1-6 o 2-8 MHz) per acquisire immagini in scala di grigi sia del portale che di una vena epatica nello stesso piano di imaging e a profondità simili (Figura 1). Questo è generalmente meglio ottenuto attraverso un approccio subcostiero.</li>
	<li>Ottimizzare le immagini in base alla buona pratica clinica e fare attenzione a selezionare la regione della vena epatica lontano dalla vena cava inferiore per evitare l'influenza del flusso retrogrado.</li>
</ol>4. Imaging SHI e SHAPE
<ol><li>Attivare la modalità di imaging del contrasto SHI in modalità dual display (ad esempio, eseguendo contemporaneamente la modalità B e SHI in tempo reale) utilizzando il pulsante del pannello a sfioramento Contrasto subarmonico e attivare la modalità Contrasto. Quindi selezionare SUBH-AM sul comando rotante.<ol><li>Eseguire SHI a una frequenza di trasmissione di 2,5 MHz e ottenere i segnali ricevuti a 1,25 MHz.</li>
		<li>Utilizzare il pulse-shaping per massimizzare la generazione di segnali di microbolle subarmoniche, come un'onda quadra filtrata binomiale a finestra gaussiana con Sonazoid,21 ma questo dipende dallo scanner e dall'UCA. 17 NOTA: la scelta della frequenza di imaging e della forma dell'impulso potrebbe non essere disponibile per gli utenti finali.</li>
	</ol></li>
	<li>Confermare la pervietà del portale e della vena epatica, nonché la presenza di microbolle, che possono richiedere fino a 1-2 minuti dall'inizio dell'infusione.</li>
	<li>Attivare il codice di ottimizzazione automatizzata SHAPE per ottimizzare SHAPE compensando la profondità e l'attenuazione variabili. 22,23 Selezionare Analisi TIC sul pannello a sfioramento seguito da F6 e quindi dal pulsante k.</li>
	<li>L'algoritmo di ottimizzazione SHAPE acquisirà dati subarmonici per ogni livello di uscita acustica. Una volta completata l'acquisizione dei dati, posizionare un ROI sulla vena porta nella finestra del campione di contrasto (in alto a sinistra nella schermata Analisi TIC).<ol><li>Tracciare i dati subarmonici medi all'interno del ROI in funzione della resa acustica e adattare una curva logistica ai dati. Selezionare il punto di flesso di questa curva (o piuttosto il picco nella curva di derivata mostrata sotto) come potenza ottimizzata, poiché questo è stato dimostrato essere il punto di maggiore sensibilità SHAPE. 22,23 Una di queste curve è mostrata nella figura 2.</li>
	</ol></li>
	<li>Regolare la potenza di uscita acustica al valore identificato al punto 4.4.1, che garantirà la massima variazione delle ampiezze subarmoniche in funzione della pressione ambiente (cioè massimizzando la sensibilità di SHAPE).</li>
	<li>Acquisire dati subarmonici dalle microbolle (cioè SHAPE) in segmenti di 5-15 s durante l'infusione della sospensione UCA (Figura 3).</li>
</ol>5. Trattamento dei dati SHAPE
<ol><li>Una volta acquisito il cine-loop SHI ottimizzato (passo 5.6) selezionare "Analisi TIC" sul pannello a sfioramento.<ol><li>Assicurati che "Motion Tracking" sia attivato sul pannello a sfioramento, che regola la posizione del ROI per ogni fotogramma per compensare qualsiasi respiro o altro movimento.</li>
		<li>Assicuratevi che dB sia selezionato come unità per l'asse Y sulle tracce nella finestra di analisi.</li>
	</ol></li>
	<li>Nella finestra del campione di contrasto (in alto a sinistra sullo schermo) selezionare ROI identici (le regioni ellittiche sono predefinite) all'interno delle vene epatiche e porta. Nella finestra di analisi (a destra) il segnale subarmonico (in dB) all'interno di ciascun recipiente viene mediato su tutti i frame in una larghezza di banda di 0,5 MHz intorno a 1,25 MHz.</li>
	<li>Calcolare il gradiente finale SHAPE (in dB) come differenza nel segnale subarmonico medio tra il ROI della vena epatica e quella della vena porta. Sulla base degli studi attuali, il punto operativo ottimale per identificare il CSPH è -0,11 dB e l'equazione di regressione lineare è HVPG = 0,81 x SHAPE + 9,43. 14 È importante notare che questo limite e questa equazione dipendono sia dallo scanner che dall'UCA.</li>
</ol>

<ol>
	<li>Lyshchik, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fundamentals of CEUS. , (2019).</li><li>Leighton, T. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Acoustic Bubble. , (1994).</li><li>Forsberg, F., Shi, W. T., Goldberg, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subharmonic+imaging+of+contrast+agents.">Subharmonic imaging of contrast agents.</a> Ultrasonics. 38 (1-8), 93-98 (2000).</li><li>Forsberg, F., Piccoli, C. W., Merton, D. A., Palazzo, J. P., Hall, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Breast+lesions:+imaging+with+contrast-enhanced+subharmonic+US+-+initial+experience.">Breast lesions: imaging with contrast-enhanced subharmonic US - initial experience.</a> Radiology. 244 (3), 718-726 (2007).</li><li>Sridharan, 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=Characterizing+breast+lesions+using+quantitative+parametric+3D+subharmonic+imaging:+a+multi-center+study.">Characterizing breast lesions using quantitative parametric 3D subharmonic imaging: a multi-center study.</a> Academic Radiology. 27 (8), 1065-1074 (2020).</li><li>Forsberg, 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=Subharmonic+and+endoscopic+contrast+imaging+of+pancreatic+masses:+a+pilot+study.">Subharmonic and endoscopic contrast imaging of pancreatic masses: a pilot study.</a> Journal of Ultrasound in Medicine. 37 (1), 123-129 (2018).</li><li>Delaney, L. J., 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=Characterization+of+adnexal+masses+using+contrast-enhanced+subharmonic+imaging:+a+pilot+study.">Characterization of adnexal masses using contrast-enhanced subharmonic imaging: a pilot study.</a> Journal of Ultrasound in Medicine. 39 (5), 977-985 (2020).</li><li>Eisenbrey, J. 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=Contrast-enhanced+subharmonic+and+harmonic+ultrasound+of+renal+masses+undergoing+percutaneous+cryoablation.">Contrast-enhanced subharmonic and harmonic ultrasound of renal masses undergoing percutaneous cryoablation.</a> Academic Radiology. 22 (7), 820-826 (2015).</li><li>Gupta, I., 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=Transrectal+subharmonic+ultrasound+imaging+for+prostate+cancer+detection.">Transrectal subharmonic ultrasound imaging for prostate cancer detection.</a> Urology. 138 (4), 106-112 (2020).</li><li>Shi, W. T., Forsberg, F., Raichlen, J. S., Needleman, L., Goldberg, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pressure+dependence+of+subharmonic+signals+from+contrast+microbubbles.">Pressure dependence of subharmonic signals from contrast microbubbles.</a> Ultrasound in Medicine and Biology. 25 (2), 275-283 (1999).</li><li>Halldorsdottir, V. G., 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=Subharmonic+contrast+microbubble+signals+for+noninvasive+pressure+estimation+under+static+and+dynamic+flow+conditions.">Subharmonic contrast microbubble signals for noninvasive pressure estimation under static and dynamic flow conditions.</a> Ultrasonic Imaging. 33 (3), 153-164 (2011).</li><li>Nio, A. Q. X., 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=Optimal+control+of+SonoVue+microbubbles+to+estimate+hydrostatic+pressure.">Optimal control of SonoVue microbubbles to estimate hydrostatic pressure.</a> IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control. 67 (3), 557-567 (2020).</li><li>Eisenbrey, J. 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=Chronic+liver+disease:+noninvasive+subharmonic+aided+pressure+estimation+of+hepatic+venous+pressure+gradient.">Chronic liver disease: noninvasive subharmonic aided pressure estimation of hepatic venous pressure gradient.</a> Radiology. 268 (2), 581-588 (2013).</li><li>Gupta, I., 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=Diagnosing+portal+hypertension+with+noninvasive+subharmonic+pressure+estimates+from+an+ultrasound+contrast+agent.">Diagnosing portal hypertension with noninvasive subharmonic pressure estimates from an ultrasound contrast agent.</a> Radiology. , (2020).</li><li>Nam, K., 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=Monitoring+neoadjuvant+chemotherapy+for+breast+cancer+by+using+three-dimensional+subharmonic+aided+pressure+estimation+and+imaging+with+US+contrast+agents:+preliminary+experience.">Monitoring neoadjuvant chemotherapy for breast cancer by using three-dimensional subharmonic aided pressure estimation and imaging with US contrast agents: preliminary experience.</a> Radiology. 285 (1), 53-62 (2017).</li><li>Dave, J. K., 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=Non-invasive+intra-cardiac+pressure+measurements+using+subharmonic-aided+pressure+estimation:+proof+of+concept+in+humans.">Non-invasive intra-cardiac pressure measurements using subharmonic-aided pressure estimation: proof of concept in humans.</a> Ultrasound in Medicine and Biology. 43 (11), 2718-2724 (2017).</li><li>Esposito, C., Dickie, K., Forsberg, F., Dave, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developing+an+interface+and+investigating+optimal+parameters+for+real-time+intra-cardiac+subharmonic+aided+pressure+estimation.">Developing an interface and investigating optimal parameters for real-time intra-cardiac subharmonic aided pressure estimation.</a> IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control. , (2020).</li><li>Bosch, J., Groszmann, R. J., Shah, V. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolution+in+the+understanding+of+the+pathophysiological+basis+of+portal+hypertension:+How+changes+in+paradigm+are+leading+to+successful+new+treatments.">Evolution in the understanding of the pathophysiological basis of portal hypertension: How changes in paradigm are leading to successful new treatments.</a> Journal of Hepatology. 62, 121-130 (2015).</li><li>Procopet, B., Berzigotti, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosis+of+cirrhosis+and+portal+hypertension:+imaging,+non-invasive+markers+of+fibrosis+and+liver+biopsy.">Diagnosis of cirrhosis and portal hypertension: imaging, non-invasive markers of fibrosis and liver biopsy.</a> Gastroenterology Report. 5 (2), 79-89 (2017).</li><li>Dietrich, C. 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=Guidelines+and+good+clinical+practice+recommendations+for+contrast-enhanced+ultrasound+(CEUS)+in+the+liver-update+2020+WFUMB+in+cooperation+with+EFSUMB,+AFSUMB,+AIUM,+and+FLAUS.">Guidelines and good clinical practice recommendations for contrast-enhanced ultrasound (CEUS) in the liver-update 2020 WFUMB in cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS.</a> Ultrasound in Medicine and Biology. , (2020).</li><li>Gupta, I., 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+pulse+shaping+on+subharmonic+aided+pressure+estimation+in+vitro+and+in+vivo.">Effect of pulse shaping on subharmonic aided pressure estimation in vitro and in vivo.</a> Journal of Ultrasound in Medicine. 36 (1), 3-11 (2017).</li><li>Dave, J. K., 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=On+the+implementation+of+an+automated+acoustic+output+optimization+algorithm+for+subharmonic+aided+pressure+estimation.">On the implementation of an automated acoustic output optimization algorithm for subharmonic aided pressure estimation.</a> Ultrasonics. 53 (4), 880-888 (2013).</li><li>Gupta, I., Eisenbrey, J. R., Machado, P., Stanczak, M., Wallace, K., Forsberg, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+factors+impacting+subharmonic-+aided+pressure+estimation+(SHAPE).">On factors impacting subharmonic- aided pressure estimation (SHAPE).</a> Ultrasonic Imaging. 41 (1), 35-48 (2019).</li><li>Eisenbrey, J. R., Daecher, A., Kramer, M. R., Forsberg, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+needle+and+catheter+size+on+commercially+available+ultrasound+contrast+agents.">Effects of needle and catheter size on commercially available ultrasound contrast agents.</a> Journal of Ultrasound in Medicine. 34 (11), 1961-1968 (2015).</li></ol>

Forsberg, Gupta, Wallace e Eisenbrey hanno un brevetto in corso sulla tecnologia SHAPE. Il Dr. Wallace è un dipendente di GE.

La misurazione non invasiva e accurata delle pressioni all'interno del corpo umano è stata a lungo un obiettivo clinico importante ma elusivo. Il protocollo per le misure SHAPE qui presentato raggiunge questo obiettivo. La componente più critica della procedura SHAPE è l'algoritmo di ottimizzazione, poiché i dati subarmonici non acquisiti alla potenza acustica ottimale saranno scarsamente correlati con le pressioni idrostatiche. 17,22,23 La versione iniziale di questo software implementata su...

Un certo numero di diversi agenti di contrasto ecografici (UCA) sono approvati per l'uso clinico in cardiologia (in particolare opacizzazione ventricolare sinistra) e radiologia (in particolare caratterizzazione delle lesioni epatiche adulte e pediatriche) in tutto il mondo. 1 La sensibilità e la specificità dell'ecografia possono essere migliorate mediante iniezione endovenosa (IV) di microbolle riempite di gas (diametro < 10 μm) incapsulate da un guscio lipidico o proteico come UCA che attraversano l'intera vascolarizzazione e potenziano i segnali fino a 30 dB. 1 Questi UCA non solo potenziano i segnali ultrasonici retrodiffusi, ma a pressioni acustiche sufficienti (> 200 kPa) fungono anche da oscillatori non lineari. Quindi, significative componenti energetiche saranno prodotte negli echi ricevuti che vanno dalle frequenze subarmoniche e armoniche a quelle ultraarmoniche. 1,2 Questi componenti del segnale non lineare possono essere estratti da echi di bolle tissutali e lineari (ad esempio, utilizzando l'inversione di impulso) e utilizzati per creare modalità di imaging specifiche per contrasto come l'imaging subarmonico (SHI), che riceve a metà della frequenza di trasmissione (cioè a f 0/2). 3 Il nostro gruppo ha dimostrato in studi clinici sull'uomo che SHI può rilevare il flusso sanguigno nei neovasi e nelle arteriole associate a una varietà di tumori e tessuti. 4,5,6,7,8,9 
Abbiamo sostenuto l'uso di UCA non come traccianti vascolari, ma come sensori per la stima non invasiva della pressione nel sistema circolatorio monitorando le variazioni di ampiezza delle bolle di contrasto subarmoniche. 10 Questa tecnica innovativa, chiamata stima della pressione assistita da subarmoniche (SHAPE), si basa sulla correlazione lineare inversa tra l'ampiezza dei segnali subarmonici e la pressione idrostatica (fino a 186 mmHg) misurata per la maggior parte degli UCA commerciali in vitro (r2 > 0,90) come riassunto nella Tabella 1. 10,11 Tuttavia, va notato che non tutti gli UCA mostrano questo comportamento. In particolare, è stato dimostrato che i segnali subarmonici provenienti dall'UCA SonoVue (noto come Lumason negli Stati Uniti) inizialmente aumentano con aumenti di pressione idrostatica, seguiti da un plateau e una fase decrescente. 12 Tuttavia, SHAPE offre la possibilità di consentire di ottenere in modo non invasivo gradienti di pressione nel cuore e in tutto il sistema cardiovascolare e la pressione del liquido interstiziale nei tumori. 13,14,15,16,17 Recentemente, abbiamo implementato una versione in tempo reale dell'algoritmo SHAPE su uno scanner a ultrasuoni commerciale e abbiamo fornito la prova del concetto che SHAPE può fornire stime della pressione in vivo con errori inferiori a 3 mmHg nei ventricoli sinistro e destro dei pazienti. 16,17
La maggior parte dell'esperienza con SHAPE fino ad oggi è stata per la diagnosi di ipertensione portale con più di 220 soggetti arruolati e i risultati iniziali confermati in uno studio multicentrico. 13,14 L'ipertensione portale è definita come un aumento del gradiente di pressione tra la vena porta e le vene epatiche o la vena cava inferiore superiore a 5 mmHg, mentre l'ipertensione portale clinicamente significativa (CSPH) richiede un gradiente o equivalente, un gradiente di pressione venosa epatica (HVPG) ≥ 10 mmHg. 18 Il CSPH è associato ad un aumentato rischio di varici gastroesofagee, ascite, scompenso epatico, scompenso post-operatorio e carcinoma epatocellulare. 18,19 I pazienti che sviluppano ascite hanno una mortalità a tre anni del 50% e quelli che sviluppano un'infezione spontanea del liquido dell'ascite portano una mortalità del 70% a un anno. I pazienti con cirrosi hanno un'incidenza annuale del 5-10% di formazione variceale gastroesofagea e un'incidenza annuale del 4-15% di sanguinamento; Ogni episodio di sanguinamento comporta fino al 20% di rischio di morte. 18,19
Questo manoscritto descrive come condurre uno studio SHAPE utilizzando apparecchiature disponibili in commercio e UCA con particolare attenzione all'identificazione dell'ipertensione portale nel fegato dei pazienti. La procedura di calibrazione critica necessaria per ottenere la massima sensibilità alla stima delle variazioni di pressione è spiegata in dettaglio.

<table>
	<tbody>
		<tr>
			<td>2 mL syringe</td>
			<td>Becton Dickinson</td>
			<td>309637</td>
			<td>Used for reconstituting Sonazoid</td>
		</tr>
		<tr>
			<td>10 mL saline-filled syringe</td>
			<td>Becton Dickinson</td>
			<td>306545</td>
			<td>Used for flushing line to verify IV access</td>
		</tr>
		<tr>
			<td>500 mL saline bag</td>
			<td>Baxter Healthcare Corp</td>
			<td>2131323</td>
			<td>Used for co-infusion with Sonazoid</td>
		</tr>
		<tr>
			<td>C1-6-D curvi-linear proble</td>
			<td>GE Healthcare</td>
			<td>H40472LT</td>
			<td>Used for liver imaging</td>
		</tr>
		<tr>
			<td>Chemoprotect Spike</td>
			<td>Codan USA</td>
			<td>C355</td>
			<td>Chemospike used for reconstituting Sonazoid</td>
		</tr>
		<tr>
			<td>Discofix C Blue</td>
			<td>B. Braun Medical Inc</td>
			<td>16494C</td>
			<td>3-way stopcock</td>
		</tr>
		<tr>
			<td>Intrafix Safeset 180 cm</td>
			<td>B. Braun Medical Inc</td>
			<td>4063000</td>
			<td>Infusion tubing</td>
		</tr>
		<tr>
			<td>Logiq E10 ultrasound scanner</td>
			<td>GE Healthcare</td>
			<td>H4928US</td>
			<td>Used for conventional ultrasound imaging as well as for SHI and SHAPE</td>
		</tr>
		<tr>
			<td>Luer lock 10 mL syringe</td>
			<td>Becton Dickinson</td>
			<td>300912</td>
			<td>For infusion of Sonazoid</td>
		</tr>
		<tr>
			<td>Medfusion 3500 syringe pump</td>
			<td>Smiths Medical</td>
			<td>3500-500</td>
			<td>Used for infusing Sonazoid at 0.18 mL/kg/hour</td>
		</tr>
		<tr>
			<td>Perfusor-leitung tubing 150 mm</td>
			<td>B. Braun Medical Inc</td>
			<td>8722960</td>
			<td>Extension line enabling syringe connection to patient&#39;s IV access</td>
		</tr>
		<tr>
			<td>SHI/SHAPE software</td>
			<td>GE Healthcare</td>
			<td>H4920CI</td>
			<td>Contrast-specific imaging software</td>
		</tr>
		<tr>
			<td>Sigma Spectrum infusion system</td>
			<td>Baxter Healthcare Corp</td>
			<td>35700BAX</td>
			<td>Pump used for co-infusing saline at 120 mL/hour</td>
		</tr>
		<tr>
			<td>Sonazoid</td>
			<td>GE Healthcare</td>
			<td></td>
			<td>Gas-filled microbubble based ultrasound contrast agent</td>
		</tr>
		<tr>
			<td>sterile water, 2 mL</td>
			<td>B. Braun Medical Inc</td>
			<td></td>
			<td>Used for reconstituting Sonazoid</td>
		</tr>
		<tr>
			<td>ultrasound gel</td>
			<td>Cardinal Health</td>
			<td>USG-250BT</td>
			<td>Used for contact between probe and patient</td>
		</tr>
		<tr>
			<td>Venflon IV cannula 22GA</td>
			<td>Becton Dickinson</td>
			<td>393202</td>
			<td>Cannula needle for obtaining IV access</td>
		</tr>
	</tbody>
</table>

contrast-enhanced subharmonic aided pressure estimation (shape) using ultrasound imaging with a focus on identifying portal hypertension

La misurazione non invasiva e accurata delle pressioni all'interno del corpo umano è stata a lungo un obiettivo clinico importante ma elusivo. Gli agenti di contrasto per l'imaging a ultrasuoni sono microbolle incapsulate con gas (diametro < 10 μm) che attraversano l'intera vascolarizzazione e migliorano i segnali fino a 30 dB. Queste microbolle producono anche oscillazioni non lineari a frequenze che vanno dalla subarmonica (metà della frequenza di trasmissione) alle armoniche superiori. L'ampiezza subarmonica ha una relazione lineare inversa con la pressione idrostatica ambiente. Qui viene presentato un sistema a ultrasuoni in grado di eseguire in tempo reale, la stima della pressione subarmonica assistita (SHAPE). Durante l'infusione di mezzo di contrasto ad ultrasuoni, viene attivato un algoritmo per l'ottimizzazione delle uscite acustiche. A seguito di questa calibrazione, i segnali a microbolle subarmoniche (cioè SHAPE) hanno la massima sensibilità alle variazioni di pressione e possono essere utilizzati per quantificare la pressione in modo non invasivo. L'utilità della procedura SHAPE per identificare l'ipertensione portale nel fegato è l'enfasi qui, ma la tecnica ha applicabilità in molti scenari clinici.

Come per tutti gli esami ecografici, la prima considerazione per la SHAPE epatica è quella di ottenere le migliori immagini possibili in scala di grigi di base della regione bersaglio e di garantire (utilizzando l'imaging Doppler) che non siano presenti shunt venosi portale intraepatici o altre anomalie vascolari. Nel caso dell'imaging epatico per la diagnosi di ipertensione portale, la chiave è visualizzare sia la vena porta che una vena epatica alla stessa profondità per ridurre al minimo l'impatto dell'attenuazione...

Watch this Scientific Journal Video about Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension at JoVE.com

Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

Un protocollo per la stima non invasiva delle pressioni ambientali utilizzando l'imaging ecografico subarmonico di microbolle di contrasto infuse (dopo appropriata calibrazione) è descritto con esempi di pazienti umani con malattia epatica cronica.

Stima della pressione subarmonica assistita da contrasto (SHAPE) utilizzando l'imaging a ultrasuoni con particolare attenzione all'identificazione dell'ipertensione portale

Noninvasive, accurate measurement of pressures within the human body has long been an important but elusive clinical goal. Contrast agents for ultrasound ...

contrast-enhanced-subharmonic-aided-pressure-estimation-shape-using

Research

JoVE Journal

Bioengineering

Contrast-Enhanced Subharmonic Aided Pressure Estimation (SHAPE) Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

2.2K Views.  Thomas Jefferson University. Un protocollo per la stima non invasiva delle pressioni ambientali utilizzando l'imaging ecografico subarmonico di microbolle di contrasto infuse (dopo appropriata calibrazione) è descritto con esempi di pazienti umani con malattia epatica cronica.

Video: Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

Shape Memory Polymers for Active Cell Culture

Shape memory polymers (SMPs) are a class of "smart" materials that have the ability to change from a fixed, temporary shape to a pre-determined permanent shape upon the application of a stimulus such as heat1-5. In a typical shape memory cycle, the SMP is first deformed at an elevated temperature that is higher than its transition temperature, Ttrans [either the melting temperature (Tm) or the glass transition temperature (Tg)]. The deformation is elastic in nature and mainly leads to a reduction in conformational entropy of the constituent network chains (following the rubber elasticity theory). The deformed SMP is then cooled to a temperature below its Ttrans while maintaining the external strain or stress constant. During cooling, the material transitions to a more rigid state (semi-crystalline or glassy), which kinetically traps or "freezes" the material in this low-entropy state leading to macroscopic shape fixing. Shape recovery is triggered by continuously heating the material through Ttrans under a stress-free (unconstrained) condition. By allowing the network chains (with regained mobility) to relax to their thermodynamically favored, maximal-entropy state, the material changes from the temporary shape to the permanent shape.
Cells are capable of surveying the mechanical properties of their surrounding environment6. The mechanisms through which mechanical interactions between cells and their physical environment control cell behavior are areas of active research. Substrates of defined topography have emerged as powerful tools in the investigation of these mechanisms. Mesoscale, microscale, and nanoscale patterns of substrate topography have been shown to direct cell alignment, cell adhesion, and cell traction forces7-14. These findings have underscored the potential for substrate topography to control and assay the mechanical interactions between cells and their physical environment during cell culture, but the substrates used to date have generally been passive and could not be programmed to change significantly during culture. This physical stasis has limited the potential of topographic substrates to control cells in culture.
Here, active cell culture (ACC) SMP substrates are introduced that employ surface shape memory to provide programmed control of substrate topography and deformation. These substrates demonstrate the ability to transition from a temporary grooved topography to a second, nearly flat memorized topography. This change in topography can be used to control cell behavior under standard cell culture conditions.

A method for developing cell culture substrates with the ability to change topography during culture is described. The method makes use of smart materials known as shape memory polymers that have the ability to memorize a permanent shape. This concept is adaptable to a wide range of materials and applications.

Shape Memory Polymers per la Cultura cella attiva

Shape memory polymers (SMPs) are a class of "smart" materials that have the ability to change from a fixed, temporary shape to a pre-determined permanent ...

Ricerca

Bioingegneria

Wideband Optical Detector of Ultrasound for Medical Imaging Applications

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic imaging. In medical applications, one of the major limitations of optical sensing technology is its susceptibility to environmental conditions, e.g. changes in pressure and temperature, which may saturate the detection. Additionally, the clinical environment often imposes stringent limits on the size and robustness of the sensor. In this work, the combination of pulse interferometry and fiber-based optical sensing is demonstrated for ultrasound detection. Pulse interferometry enables robust performance of the readout system in the presence of rapid variations in the environmental conditions, whereas the use of all-fiber technology leads to a mechanically flexible sensing element compatible with highly demanding medical applications such as intravascular imaging. In order to achieve a short sensor length, a pi-phase-shifted fiber Bragg grating is used, which acts as a resonator trapping light over an effective length of 350 &#181;m. To enable high bandwidth, the sensor is used for sideway detection of ultrasound, which is highly beneficial in circumferential imaging geometries such as intravascular imaging. An optoacoustic imaging setup is used to determine the response of the sensor for acoustic point sources at different positions.

Optical detection of ultrasound is impractical in many imaging scenarios because it often requires stable environmental conditions. We demonstrate an optical technique for ultrasound sensing in volatile environments with miniaturization and sensitivity levels appropriate for optoacoustic imaging in restrictive scenarios, e.g. intravascular applications.

Wideband rivelatore ottico di ultrasuono per applicazioni Medical Imaging

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic ...

Microfluidic Fabrication of Polymeric and Biohybrid Fibers with Predesigned Size and Shape

A &#8220;sheath&#8221; fluid passing through a microfluidic channel at low Reynolds number can be directed around another &#8220;core&#8221; stream and used to dictate the shape as well as the diameter of a core stream.&#160;Grooves in the top and bottom of a microfluidic channel were designed to direct the sheath fluid and shape the core fluid.&#160;By matching the viscosity and hydrophilicity of the sheath and core fluids, the interfacial effects are minimized and complex fluid shapes can be formed.&#160;Controlling the relative flow rates of the sheath and core fluids determines the cross-sectional area of the core fluid.&#160;Fibers have been produced with sizes ranging from 300 nm to ~1 mm, and fiber cross-sections can be round, flat, square, or complex as in the case with double anchor fibers. Polymerization of the core fluid downstream from the shaping region solidifies the fibers.&#160;Photoinitiated click chemistries are well suited for rapid polymerization of the core fluid by irradiation with ultraviolet light.&#160;Fibers with a wide variety of shapes have been produced from a list of polymers including liquid crystals, poly(methylmethacrylate), thiol-ene and thiol-yne resins, polyethylene glycol, and hydrogel derivatives. Minimal shear during the shaping process and mild polymerization conditions also makes the fabrication process well suited for encapsulation of cells and other biological components.

Two adjacent fluids passing through a grooved microfluidic channel can be directed to form a sheath around a prepolymer core; thereby&#160;determining both shape and cross-section. Photoinitiated polymerization, such as thiol click chemistry, is well suited for rapidly solidifying the core fluid into a microfiber with predetermined size and shape.

Fabbricazione microfluidica di fibre polimeriche e bioibride con dimensioni e forma predesignate

A &#8220;sheath&#8221; fluid passing through a microfluidic channel at low Reynolds number can be directed around another &#8220;core&#8221; stream and ...

Fabrication of a Bioactive, PCL-based "Self-fitting" Shape Memory Polymer Scaffold

Tissue engineering has been explored as an alternative strategy for the treatment of critical-sized cranio-maxillofacial (CMF) bone defects. Essential to the success of this approach is a scaffold that is able to conformally fit within an irregular defect while also having the requisite biodegradability, pore interconnectivity and bioactivity. By nature of their shape recovery and fixity properties, shape memory polymer (SMP) scaffolds could achieve defect &#8220;self-fitting.&#8221; In this way, following exposure to warm saline (~60 &#186;C), the SMP scaffold would become malleable, permitting it to be hand-pressed into an irregular defect. Subsequent cooling (~37 &#186;C) would return the scaffold to its relatively rigid state within the defect. To meet these requirements, this protocol describes the preparation of SMP scaffolds prepared via the photochemical cure of biodegradable polycaprolactone diacrylate (PCL-DA) using a solvent-casting particulate-leaching (SCPL) method. A fused salt template is utilized to achieve pore interconnectivity. To realize bioactivity, a polydopamine coating is applied to the surface of the scaffold pore walls. Characterization of self-fitting and shape memory behaviors, pore interconnectivity and in vitro bioactivity are also described.

Fabrication of a Bioactive, PCL-based &quot;Self-fitting&quot; Shape Memory Polymer Scaffold

Scaffolds capable of fitting within cranio-maxillofacial (CMF) bone defects while exhibiting osteoconductivity and bioactivity are of interest. This protocol describes the preparation of a shape memory scaffold based on polycaprolactone diacrylate (PCL-DA) using a solvent-casting particulate-leaching (SCPL) method employing a fused salt template and application of a bioactive polydopamine coating.

Realizzazione di una sede a PCL Bioactive, &quot;Self-fitting&quot; Shape Memory Polymer Ponteggio

Tissue engineering has been explored as an alternative strategy for the treatment of critical-sized cranio-maxillofacial (CMF) bone defects. Essential to ...

Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An oscillatory motion is generated at the focus of a 93-element and 4.5 MHz center frequency HIFU transducer by applying a 25 Hz amplitude-modulated signal using a function generator. A 64-element and 2.5 MHz imaging transducer with 68kPa peak pressure is confocally placed at the center of the HIFU transducer to acquire the radio-frequency (RF) channel data. In this protocol, real-time monitoring of thermal ablation using HIFU with an acoustic power of 7 W on canine livers in vitro is described. HIFU treatment is applied on the tissue during 2 min and the ablated region is imaged in real-time using diverging or plane wave imaging up to 1,000 frames/second. The matrix of RF channel data is multiplied by a sparse matrix for image reconstruction. The reconstructed field of view is of 90&#176; for diverging wave and 20 mm for plane wave imaging and the data are sampled at 80 MHz. The reconstruction is performed on a Graphical Processing Unit (GPU) in order to image in real-time at a 4.5 display frame rate. 1-D normalized cross-correlation of the reconstructed RF data is used to estimate axial displacements in the focal region. The magnitude of the peak-to-peak displacement at the focal depth decreases during the thermal ablation which denotes stiffening of the tissue due to the formation of a lesion. The displacement signal-to-noise ratio (SNRd) at the focal area for plane wave was 1.4 times higher than for diverging wave showing that plane wave imaging appears to produce better displacement maps quality for HMIFU than diverging wave imaging.

Real-time Monitoring of High Intensity Focused Ultrasound HIFU Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound HMIFU

This article describes real-time monitoring of HIFU ablation in canine liver with high frame rate ultrasound imaging using diverging and plane wave imaging. Harmonic Motion Imaging for Focused Ultrasound is used to image the decrease of acoustic radiation force induced displacement in the ablated region.

Monitoraggio in tempo reale di alta intensità ultrasuoni focalizzati (HIFU) Ablazione<em&gt; In Vitro</em&gt; Canine Livers Uso Harmonic Imaging Movimento per Focused Ultrasound (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An ...

Double Emulsion Generation Using a Polydimethylsiloxane (PDMS) Co-axial Flow Focus Device

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper presents a polydimethylsiloxane (PDMS) microfluidic device capable of generating water/oil/water double emulsions using a coaxial flow focusing geometry that can be fabricated entirely using soft lithography. Similar to emulsion devices using glass capillaries, double emulsions can be formed in channels with uniform wettability and with dimensions much smaller than the channel sizes. Three dimensional flow focusing geometry is achieved by casting a pair of PDMS slabs using two layer soft lithography, then mating the slabs together in a clamshell configuration. Complementary locking features molded into the PDMS slabs enable the accurate registration of features on each of the slab surfaces. Device testing demonstrates formation of double emulsions from 14 &#181;m to 50 &#181;m in diameter while using large channels that are robust against fouling and clogging.

Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device

Microfluidic double emulsions generation typically involves devices with patterned wettability or custom-fabricated glass components. Here we describe the fabrication and testing of an all polydimethylsiloxane (PDMS) double emulsion generator that does not require surface treatment or complicated fabrication processes, and is capable of producing double emulsions down to 14 &#181;m.

Doppia Emulsione Generazione Utilizzando un Polidimetilsilossano (PDMS) coassiale flusso fuoco Dispositivo

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper ...

Conducting Multiple Imaging Modes with One Fluorescence Microscope

Fluorescence microscopy is a powerful tool to detect biological molecules in situ and monitor their dynamics and interactions in real-time. In addition to conventional epi-fluorescence microscopy, various imaging techniques have been developed to achieve specific experimental goals. Some of the widely used techniques include single-molecule fluorescence resonance energy transfer (smFRET), which can report conformational changes and molecular interactions with angstrom resolution, and single-molecule detection-based super-resolution (SR) imaging, which can enhance the spatial resolution approximately ten&#160;to twentyfold compared to diffraction-limited microscopy. Here we present a customer-designed integrated system, which merges multiple imaging methods in one microscope, including conventional epi-fluorescent imaging, single-molecule detection-based SR imaging, and multi-color single-molecule detection, including smFRET imaging. Different imaging methods can be achieved easily and reproducibly by switching optical elements. This set-up is easy to adopt by any research laboratory in biological sciences with a need for routine and diverse imaging experiments at a reduced cost and space relative to building separate microscopes for individual purposes.

Here we present a practical guide of building an integrated microscopy system, which merges conventional epi-fluorescent imaging, single-molecule detection-based super-resolution imaging, and multi-color single-molecule detection, including single-molecule fluorescence resonance energy transfer imaging, into one set-up in a cost-efficient way.

Lo svolgimento di diverse modalità di Imaging con un microscopio a fluorescenza

Fluorescence microscopy is a powerful tool to detect biological molecules in situ and monitor their dynamics and interactions in real-time. In addition to ...

Material Formation of Recombinant Spider Silks through Aqueous Solvation using Heat and Pressure

Many spiders produce seven types of silks. Six of the silks are fiber in form when produced by the spiders. These fibers are not water soluble. In order to reproduce the remarkable mechanical properties of spider silks, they must be produced in heterologous hosts as spiders are both territorial and cannibalistic. The synthetic analogs of spider silk also tend to be insoluble in aqueous solutions. Thus, a large percentage of research in recombinant spider silks rely upon organic solvents that are detrimental to large scale production of materials. Our group&#8217;s method forces the solvation of these recombinant spider silks into water. Remarkably, when these proteins are prepared using this method of heat and pressure, a wide range of material forms can be prepared from the same solution of recombinant spider silk proteins (rSSp) including: films, fibers, sponge, hydrogel, lyogel, and adhesives. This article demonstrates the production of the solvated rSSp and material forms in a manner that is more easily understood than from written materials and methods alone.

Here, we present a protocol to produce water soluble recombinant spider silk protein solutions and the material forms that can be formed from those solutions.

Formazione del materiale di sete di ragno ricombinante attraverso la Solvazione acquosa utilizzando calore e pressione

Many spiders produce seven types of silks. Six of the silks are fiber in form when produced by the spiders. These fibers are not water soluble. In order ...

Patient-Specific Polyvinyl Alcohol Phantom Fabrication with Ultrasound and X-Ray Contrast for Brain Tumor Surgery Planning

Phantoms are essential tools for clinical training, surgical planning and the development of novel medical devices. However, it is challenging to create anatomically accurate head phantoms with realistic brain imaging properties because standard fabrication methods are not optimized to replicate any patient-specific anatomical detail and 3D printing materials are not optimized for imaging properties. In order to test and validate a novel navigation system for use during brain tumor surgery, an anatomically accurate phantom with realistic imaging and mechanical properties was required. Therefore, a phantom was developed using real patient data as input and 3D printing of molds to fabricate a patient-specific head phantom comprising the skull, brain and tumor with both ultrasound and X-ray contrast. The phantom also had mechanical properties that allowed the phantom tissue to be manipulated in a similar manner to how human brain tissue is handled during surgery. The phantom was successfully tested during a surgical simulation in a virtual operating room.
The phantom fabrication method uses commercially available materials and is easy to reproduce. The 3D printing files can be readily shared, and the technique can be adapted to encompass many different types of tumor.

This protocol describes the fabrication of a patient specific skull, brain and tumor phantom. It uses 3D printing to create molds, and polyvinyl alcohol (PVA-c) is used as the tissue mimicking material.

Fabbricazione fantasma di alcol polivinile specifico per il paziente con ultrasuoni e contrasto a raggi X per la pianificazione della chirurgia del tumore al cervello

Phantoms are essential tools for clinical training, surgical planning and the development of novel medical devices. However, it is challenging to create ...

High-Dimensionality Flow Cytometry for Immune Function Analysis of Dissected Implant Tissues

The success of implanting laboratory-grown tissue or a medical device in an individual is subject to the immune response of the recipient host. Considering an implant as a foreign body, a hostile and dysregulated immune response may result in the rejection of the implant, while a regulated response and regaining of homeostasis can lead to its acceptance. Analyzing the microenvironments of implants dissected out under in vivo or ex vivo&#160;settings can help in understanding the pattern of immune response, which can ultimately help in developing new generations of biomaterials. Flow cytometry is a well-known technique for characterizing immune cells and their subsets based on their cell surface markers. This review describes a protocol based on manual dicing, enzymatic digestion, and filtration through a cell strainer for the isolation of uniform cell suspensions from dissected implant tissue. Further, a multicolor flow cytometry staining protocol has been explained, along with steps for initial cytometer settings to characterize and quantify these isolated cells by flow cytometry.

Isolation of cells from dissected implants and their characterization by flow cytometry can significantly contribute to understanding the pattern of immune response against implants. This paper describes a precise method for the isolation of cells from dissected implants and their staining for flow cytometric analysis.