1. Preparação da placenta <ol><li> A placenta deve ser adquirido a partir da sala de parto o mais cedo possível após o parto para minimizar a formação de coágulos dessecação, e da deterioração geral do tecido. </li><li> Cuidados devem ser tomados para garantir que a placenta não está exposta a fixação em formalina ou outro. </li><li> Padrão BSL2 precauções para tecidos humanos devem ser mantidas e pessoal deve usar uma máscara, avental, luvas e proteção para os sapatos. </li><li> Coloque a placenta em uma tigela grande de plástico ou metal que tem buracos precut para permitir a drenagem do fluido. Esta taça deve ser colocado dentro de uma tigela grande de aço inoxidável para evitar derramamento. </li><li> Lavar a placenta com soro fisiológico morno. </li><li> Para melhor visualização da placenta, use uma tesoura Metzenbaum para extirpar as membranas inter-twin amniótico sendo cuidado para não ferir a placenta em si. Deixe um manguito ½ cm de inter-twin de membrana no local. (Figura 1A). </li></ol> 2. Cateterismo dos vasos da placenta <ol><li> Identificar os cabos dos gêmeos respectivos. Os obstetras costumam identificar cada gémeo pelo número de grampos colocados em cada cabo. Certifique-se de confirmar que o cabo fornecido apresentando twin (A twin). </li><li> Um de cada vez, mantendo o controle de qual cabo é que, cada transecto cordão logo abaixo os grampos (Figura 1B). Delicadamente o leite coagular fora dos vasos (Figura 1C). Na borda do corte do cordão haverá uma veia e pelo menos um, geralmente dois, artérias. Artérias são identificados pelo seu diâmetro relativamente menor (em comparação com a veia) e ao redor do manguito muscular (Figura 1D). </li><li> Use um padrão de fio-guia radial arterial linha, 0,46 mm de diâmetro e 80 cm de comprimento (Arrow, Reading PA, EUA), com uma ponta macia para ter acesso a um orifício na extremidade arterial corte de cabo de gêmeos A (Figura 1E). </li><li> O fio-guia deve ser colocado um mínimo de três centímetros dentro do vaso. Tensão contra suave sobre a parcela não-vasculares da borda do corte do cabo usando uma pinça Kelly facilita muito o avanço do fio. Transformando menor do cabo para endireitar os vasos tortuosos pode ajudar com o avanço do fio. Cuidados devem ser tomados para evitar passagens falsas. </li><li> Utilizando a técnica de Seldinger thread, a 20 cm de comprimento 0,6-1,19 milímetros cateter de polietileno de diâmetro interno (Intramedic, Batavia IL, EUA) com uma extremidade chanfrada distal sem rodeios sobre o fio dentro da artéria (Figura 1F). Cuidados devem ser tomados para não deslocar o fio ao avançar o cateter. Remova o fio depois de cateter é assentado pelo menos 3 cm no vaso. </li><li> Como alternativa, alguns grupos têm tido sucesso sem o uso de um fio-guia e direta canulação dos vasos umbilicais com cateteres de artéria umbilical. Embora, esta técnica funciona bem em nossas mãos o uso de um fio-guia diminuiu o tempo que nos leva a concluir o procedimento. </li><li> Anexar um 18 G blunt ponta da agulha (BD Biosciences, Franlik Lakes, NJ, EUA) para a extremidade proximal do tubo. Assegurar a colocação adequada do cateter através da injeção de uma pequena quantidade de soro fisiológico dentro do vaso e observando limpeza das artérias distais. Varre dedo suave sobre os vasos enquanto está a injectar solução salina pode ajudar a facilitar a circulação de qualquer coágulos residual. </li><li> Repita os passos com cuidado 2,3-2,6 para a veia de um gêmeo com atenção para evitar o desprendimento do cateter arterial. </li><li> Amarre um pedaço de fita umbilical 1 cm distal do bordo de corte ao redor da medula e cateteres. Assegurar uma boa vedação para evitar o refluxo. </li><li> Repita o passo 2,3-2,9 para o cabo do gêmeo B (a não-apresentação de twin) de tal forma que existem cateteres na artéria e veia umbilical de cada dupla presa com fita umbilical e ambos circulações foram infundidos com salina (Figura 2). </li></ol> 3. Injeção de tinta colorida para os vasos da placenta <ol><li> Patologia corante, suspensões de bário, gelatina ou de outros corantes viscoso pode ser usado para visualizar a vasculatura placentária. Escolha quatro cores contrastantes com a qual a injetar as artérias e veias de gêmeos A e B. As cores para a artéria e veia para cada dupla deve ser facilmente distinguíveis. Anastomoses superficiais deve ser detectada através da mistura de corante e à formação de uma cor (mistura) de diferentes facilmente detectável. </li><li> Use uma seringa de 3 ml para a mão de injetar o corante A artéria do duplo com a baixa pressão. Suavemente varredura com um ou dois dedos ao longo dos vasos na direção do fluxo de corante para assegurar o preenchimento de toda a árvore vascular. Se uma anastomose vascular superficial é identificado, a oclusão manual do navio a alimentação pode ser empregado para permitir que o resto da cama maior resistência vascular para preencher (Figura 3A). </li><li> Use uma seringa de 3ml separados à mão injetar a artéria do gêmeo B (Figura 3B). </li><li> Repita os passos 3.2 e 3.3 para as injecções venosas. </li><li> Se houver vazamento de corante a partir de um navio feridos reparação, deve ser realizada com uma sutura fina e um motorista de agulha. Tome cuidado para não sutura ligadura do vess todoel. </li><li> Usando uma câmera de alta resolução digital de tirar uma imagem após cada injecção. Depois de todas as injecções são completos, retire a amostra da tigelas, lugar de encontro a um fundo de cor neutra e re-imagem (Figura 4). Documento o número e tipo de conexões observadas entre as circulações dos gêmeos. </li></ol> 4. Resultados representativos: Artéria para anastomoses da artéria (AA) foram mostrados para ser &quot;protetor&quot;, como eles estão associados com um risco significativo de redução da STT e com melhores resultados para ambos os gêmeos 5. A Figura 4 demonstra uma injeção MC placenta gêmea. Um AA tinha sido identificado por prospectivamente no útero de ultra-som Doppler. Este achado foi confirmado através da mistura de gêmeos arterial (amarelo) e twin B Um corante arterial (azul) em uma estrutura de comunicação arterial (verde, seta). Anastomose com a artéria da AV twin A (amarelo) e veias de gêmeos B (laranja) é também demonstrada (cabeça de seta). Figura 5 e 6 mostram fotografias de outros dois espécimes da placenta foi injetado. <img src="/files/ftp_upload/2837/2837fig1.jpg" alt="Figura 1"/> Figura 1. (A) A membrana amniótica é cuidadosamente removido da superfície fetal da placenta MC compartilhada com tesoura Metzenbaum. (B) A borda limpa do cordão umbilical do gêmeo A é exposto por transecção proximal com Metzenbaum tesoura. (C) Clot é ordenhado da medula por compressão manual. (D) As artérias umbilical (pontas de seta) e veia (seta) do gêmeo A são identificados. (E) Após a colocação de uma pinça Kelly na porção avascular da superfície de corte do cabo de tração, um fio-guia é colocado na artéria umbilical do gêmeo A e gentilmente avançados através do vaso tortuoso. (F) Um pequeno cateter é então avançado sobre o fio-guia para o lúmen do vaso usando a técnica de Seldinger. <img src="/files/ftp_upload/2837/2837fig2.jpg" alt="Figura 2"/> Cateteres figura 2. Foram colocados em uma artéria umbilical e na veia umbilical de cada gêmeo. Estes cateteres são seguros no lugar com laços de fita umbilical ao redor do cordão inteiro. O posicionamento correto de cada cateter foi confirmada e coágulos intraluminais foram apuradas pela injeção de soro fisiológico aquecido. <img src="/files/ftp_upload/2837/2837fig3.jpg" alt="Figura 3"/> Figura 3. (A) A circulação arterial do gêmeo A é injetado com corante amarelo. Contrastar claramente passa através do equador vascular para a circulação arterial de gêmeos B. (B) A circulação arterial da B twin é injetado com tinta azul. Admixing do corante amarelo e azul resultados corante em corante verde dentro da AA demonstrou anastomose (seta). <img src="/files/ftp_upload/2837/2837fig4.jpg" alt="Figura 4"/> Figura 4. A veia do gêmeo A (vermelho) e da veia do gêmeo B (laranja) foram injetados. A anastomose AA (seta) e uma anastomose AV, com fluxo direcionado de A para twin twin B, (cabeça de seta) são delineadas. <img src="/files/ftp_upload/2837/2837fig5.jpg" alt="Figura 5"/> Figura 5. Exemplo de MC twin placenta que foram submetidos a terapia com laser após a injeção pós-natal. Artéria o gêmeo doador ea veia estão em, respectivamente, amarelo e verde. A artéria e veia destinatário estão em azul e laranja, respectivamente. Nenhuma conexão residual entre as circulações foram detectados. <img src="/files/ftp_upload/2837/2837fig6.jpg" alt="Figura 6"/> Figura 6. Exemplo de MC twin placenta após a injeção. Artéria o gêmeo do lado esquerdo e veias são em amarelo e vermelho, respectivamente. O gêmeo artéria do lado direito e veias são em azul e laranja, respectivamente. Um AA (seta) e VV (seta) são visíveis na superfície da placenta.

<ol>
	<li>Rand, L., Lee, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complicated+monochorionic+twin+pregnancies:+updates+in+fetal+diagnosis+and+treatment.">Complicated monochorionic twin pregnancies: updates in fetal diagnosis and treatment.</a> Clin Perinatol. 36, 417-430 (2009).</li><li>Sebire, N., Talbert, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Twin-to-twin+transfusion+syndrome+results+from+dynamic+asymmetrical+reduction+in+placental+anastomoses:+a+hypothesis.">Twin-to-twin transfusion syndrome results from dynamic asymmetrical reduction in placental anastomoses: a hypothesis.</a> in Placenta. , (2001).</li><li>Machin, G. A., Keith, L. 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> An atlas of multiple pregnancy: biology and pathology. , (1999).</li><li>Machin, G. A., Feldstein, V. A., van Gemert, M. J., Keith, L. G., Hecher, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doppler+sonographic+demonstration+of+arterio-venous+anastomosis+in+monochorionic+twin+gestation.">Doppler sonographic demonstration of arterio-venous anastomosis in monochorionic twin gestation.</a> Ultrasound Obstet Gynecol. 16, 214-217 (2000).</li><li>Denbow, M. L., Cox, P., Taylor, M., Hammal, D. M., Fisk, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Placental+angioarchitecture+in+monochorionic+twin+pregnancies:+Relationship+to+fetal+growth,+fetofetal+transfusion+syndrome,+and+pregnancy+outcome.">Placental angioarchitecture in monochorionic twin pregnancies: Relationship to fetal growth, fetofetal transfusion syndrome, and pregnancy outcome.</a> American Journal of Obstetrics and Gynecology. 182, 417-426 (2000).</li><li>Taylor, M. J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doppler+detection+of+arterio-arterial+anastomoses+in+monochorionic+twins:+feasibility+and+clinical+application.">Doppler detection of arterio-arterial anastomoses in monochorionic twins: feasibility and clinical application.</a> Human Reproduction. 15, 1632-1636 (2000).</li><li>Berm&#250;dez, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Placental+types+and+twin-twin+transfusion+syndrome.">Placental types and twin-twin transfusion syndrome.</a> American Journal of Obstetrics and Gynecology. 187, 489-494 (2002).</li><li>Lewi, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intertwin+anastomoses+in+monochorionic+placentas+after+fetoscopic+laser+coagulation+for+twin-to-twin+transfusion+syndrome:+is+there+more+than+meets+the+eye.">Intertwin anastomoses in monochorionic placentas after fetoscopic laser coagulation for twin-to-twin transfusion syndrome: is there more than meets the eye.</a> Am J Obstet Gynecol. 194, 790-795 (2006).</li><li>Wee, L. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation+of+deep+arterio-venous+anastomoses+within+monochorionic+placentae+by+vascular+casting.">Characterisation of deep arterio-venous anastomoses within monochorionic placentae by vascular casting.</a> Placenta. 26, 19-24 (2005).</li><li>Paepe, M. E. D. e., Burke, S., Luks, F. I., Pinar, H., Singer, D. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+placental+vascular+anatomy+in+monochorionic+twin+gestations.">Demonstration of placental vascular anatomy in monochorionic twin gestations.</a> Pediatr Dev Pathol. 5, 37-44 (2002).</li></ol>

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Mapeamento vascular da placenta MC twin por injeção de corante é um procedimento valioso para a avaliação complicada, casos clinicamente tratados e para reforçar ainda mais a nossa compreensão da geminação MC. Coordenação com a equipe obstétrica para garantir a aquisição rápida de uma amostra intacta placentária é crucial. Dessecação ou armazenamento prolongado do tecido antes da injeção pode levar à lesão do vaso e extravasamento de corante. Fixação da placenta deve ser evitado, pois os coágul...

<table border="1"><tbody><tr><th> Nome do reagente </th><th> Companhia </th><th> Número de catálogo </th><th> Comentários (opcional) </th></tr><tr><td> Tigela de plástico perfurado </td><td> Equipamentos Médicos e Suprimentos QuickMedical </td><td> Polarware PA75 </td><td> Perfurações podem ser feitos com uma broca </td></tr><tr><td> Tigela de aço inoxidável </td><td> Narang Medical Limited </td><td> HH517 </td><td></td></tr><tr><td> Soro fisiológico </td><td> Pescador </td><td> 50983204 </td><td></td></tr><tr><td> 0,6-1,9 milímetros tubos de polietileno ID </td><td> Intramedic </td><td> 7436 </td><td></td></tr><tr><td> Arterial fio-guia de linha (0,46 mm) </td><td> Arrow International </td><td> PW-18080 </td><td> Ponta macia </td></tr><tr><td> 18 G Agulhas Blunt </td><td> BD Biosciences </td><td> 305180 </td><td></td></tr><tr><td> Fita Umbilical </td><td> Fornecimento QC </td><td> 140895 </td><td></td></tr><tr><td> Metzenbaum tesoura </td><td> Cole-Parmer </td><td> EW-10921-04 </td><td></td></tr><tr><td> Kelly clamp </td><td> Cole Parmer </td><td> EW-10918-20 </td><td></td></tr><tr><td> Seringa de 3 ml </td><td> Covidien </td><td> 1180300555 </td><td></td></tr><tr><td> Patologia Dye </td><td> Bradley Produtos </td><td> 7365-x </td><td></td></tr><tr><td> Câmera Digital </td><td> Panasonic </td><td> Lumix TZ50- </td><td></td></tr></tbody></table>

guide wire assisted catheterization and colored dye injection for vascular mapping of monochorionic twin placentas

Gravidezes monocoriônicas (MC) twin estão associadas à morbidade significativamente maior e as taxas de mortalidade do que os gêmeos dicoriônicas. Aproximadamente 50% das gestações MC twin desenvolver complicações decorrentes da placenta compartilhada e conexões associadas vascular 1. Síndrome gêmeo-à-gêmea severa (STT) é relatado para responsáveis ​​por aproximadamente 20% desses 2,3 complicações. Inter-twin conexões vasculares ocorrem em quase todas as placentas MC e estão relacionados com o prognóstico e os resultados dessas gestações de alto risco individuais. O número, tamanho e tipo de conexões têm sido implicados no desenvolvimento da STT e outros MC condições individuais. Três tipos de inter-conexões twin vascular ocorrer: 1) artéria para conexões veia (AVs) em que uma artéria que transporta sangue oxigenado ramo de um twin cursos ao longo da superfície fetal da placenta e mergulha em uma cotilédone da placenta. O sangue flui através de uma rede capilar profunda intraparenquimatosa em uma veia de drenagem que emerge na superfície fetal da placenta e traz o sangue oxigenado para o outro gêmeo. Existe fluxo unidirecional do gêmeo, suprindo a artéria aferente em direção ao twin receber a veia eferente; 2) artéria para conexões artéria (AA) em que uma artéria ramo de cada dupla atende diretamente sobre a superfície superficial placentária, resultando em um recipiente com bidirecional pulsátil fluxo, e 3) veia para conexões veia (VV), no qual uma veia de cada ramo twin atende diretamente na superfície da placenta superficial permitindo o fluxo bidirecional de baixa pressão. In utero obstétrica sonografia com Doppler interrogatório alvo tem sido usado para identificar a presença de AV e conexões AA 4. AAs pré-natal detectou que foram confirmados por estudos pós-injeção da placenta foram mostrados para ser associados com um melhor prognóstico para os dois gêmeos 5. Além disso, ablação a laser fetoscopic de inter-twin conexões vasculares na superfície fetal da placenta compartilhada agora é o tratamento preferido para o início, STT grave. Pós-natal estudos de injeção da placenta fornece um método valioso para confirmar a exatidão dos resultados de ultra-som Doppler pré-natal e da eficácia da terapia a laser fetal 6. Usando corantes separadamente mão injetado na circulação arterial e venosa de cada dupla, os destaques técnica e AVs delineia, AAs, e VV. Esta demonstração definitiva de MC anatomia vascular placentário pode então ser correlacionadas com achados ultra-som Doppler e resultado neonatal para melhorar nosso entendimento da fisiopatologia da MC de geminação e suas seqüelas. Aqui nós demonstramos a nossa técnica de injeção da placenta.

Watch this Scientific Journal Video about Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas at JoVE.com

Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas

Mapeamento vascular da monocoriônicas (MC) placentas gêmeas após o nascimento fornece um meio para a demonstração detalhada das conexões vasculares entre as circulações dos gêmeos. Desequilíbrio dessas conexões é pensado para jogar um papel crucial no desenvolvimento de complicações da geminação MC incluindo twin-to-twin síndrome de transfusão.

Guia de Cateterismo Fio Assistida e injeção de corante colorido para o Mapeamento de Vascular monocoriônicas placentas gêmeas

Monochorionic (MC) twin pregnancies are associated with significantly higher morbidity and mortality rates than dichorionic twins. Approximately 50% of MC ...

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Research

JoVE Journal

Medicine

14.8K visualizações.  University of California, San Francisco. Mapeamento vascular da monocoriônicas (MC) placentas gêmeas após o nascimento fornece um meio para a demonstração detalhada das conexões vasculares entre as circulações dos gêmeos. Desequilíbrio dessas conexões é pensado para jogar um papel crucial no desenvolvimento de complicações da geminação MC incluindo twin-to-twin síndrome de transfusão.

Vídeo: Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography

Proximal resistance vessels, such as the mesenteric arteries, contribute substantially to the peripheral resistance. These small vessels of between 100-400 &mu;m in diameter function primarily in directing blood flow to various organs according to the overall requirements of the body. The rat mesenteric artery has a diameter greater than 100 &mu;m. The myography technique, first described by Mulvay and Halpern1, was based on the method proposed by Bevan and Osher2. The technique provides information about small vessels under isometric conditions, where substantial shortening of the muscle preparation is prevented. Since force production and sensitivity of vessels to different agonists is dependent on the extent of stretch, according to active tension-length relation, it is essential to conduct contraction studies under isometric conditions to prevent compliance of the mounting wires. Stainless steel wires are preferred to tungsten wires because of oxidation of the latter, which affects recorded responses3.The technique allows for the comparison of agonist-induced contractions of mounted vessels to obtain evidence for normal function of vascular smooth muscle cell receptors.
We have shown in several studies that isolated mesenteric arteries that are contracted with phenylyephrine relax upon addition of cumulative concentrations of extracellular calcium (Ca2+e). The findings led us to conclude that perivascular sensory nerves, which express the G protein-coupled Ca2+-sensing receptor (CaR), mediate this vasorelaxation response. Using an automated wire myography method, we show here that mesenteric arteries from Wistar, Dahl salt-sensitive(DS) and Dahl salt-resistant (DR) rats respond differently to Ca2+e. Tissues from Wistar rats showed higher Ca2+-sensitivity compared to those from DR and DS. Reduced CaR expression in mesenteric arteries from DS rats correlates with reduced Ca2+e-induced relaxation of isolated, pre-contracted arteries. The data suggest that the CaR is required for relaxation of mesenteric arteries under increased adrenergic tone, as occurs in hypertension, and indicate an inherent defect in the CaR signaling pathway in Dahl animals, which is much more severe in DS.
The method is useful in determining vascular reactivity ex vivo in mesenteric resistance arteries and similar small blood vessels and comparisons between different agonists and/or antagonists can be easily and consistently assessed side-by-side6,7,8.

An automated myography method for force measurements in isolated mesenteric arteries is described. It employs a Mulvany-Halpern Auto Dual Wire Myograph 510A to determine responses to phenylephrine and extracellular calcium. The method allows consistent determination of isometric responses to agonists in small vessels of diameters of 60 - 300 &mu;m, independently.

A contração da artéria mesentérica e Estudos Relaxamento Usando Miografia Fio Automated

Proximal resistance vessels, such as the mesenteric arteries, contribute substantially to the peripheral resistance. These small vessels of between ...

Medicina

Accurate and Simple Evaluation of Vascular Anastomoses in Monochorionic Placenta using Colored Dye

The presence of placental vascular anastomoses is a conditio sine qua non for the development of twin-to-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS)1,2. Injection studies of twin placentas have shown that such anastomoses are almost invariably present in monochorionic twins and extremely rare in dichorionic twins1. Three types of anastomoses have been documented: from artery to artery, from vein to vein and from artery to vein. Arterio-venous (AV) anastomoses are unidirectional and are referred to as "deep" anastomoses since they proceed through a shared placental cotyledon, whereas arterio-arterial (AA) and veno-venous (VV) anastomoses are bi-directional and are referred to as "superficial" since they lie on the chorionic plate. Both TTTS and TAPS are caused by net imbalance of blood flow between the twins due to AV anastomoses. Blood from one twin (the donor) is pumped through an artery into the shared placental cotyledon and then drained through a vein into the circulation of the other twin (the recipient). Unless blood is pumped back from the recipient to the donor through oppositely directed deep AV anastomoses or through superficial anastomoses, an imbalance of blood volumes occurs, gradually leading to the development of TTTS or TAPS. The presence of an AA anastomosis has been shown to protect against the development of TTTS and TAPS by compensating for the circulatory imbalance caused by the uni-directional AV anastomoses1,2. 
Injection of monochorionic placentas soon after birth is a useful mean to understand the etiology of various (hematological) complications in monochorionic twins and is a required test to reach the diagnosis of TAPS2. In addition, injection of TTTS placentas treated with fetoscopic laser surgery allows identification of possible residual anastomoses3-5. This additional information is of paramount importance for all perinatologists involved in the management and care of monochorionic twins with TTTS or TAPS. Several placental injection techniques are currently being used. We provide a simple protocol to accurately evaluate the presence of (residual) vascular anastomoses using colored dye injection.

Twin-to-twin transfusion syndrome and twin anemia polycythemia sequence are two potentially devastating problems in perinatal medicine. Both disorders occur only in monochorionic twins and result from unbalanced blood flow through placental vascular anastomoses. We provide a simple protocol to accurately evaluate the presence of vascular anastomoses using colored dye injection of placental vessels after birth.

Avaliação precisas e simples de anastomoses vasculares em Placenta monocoriônicas usando Dye Colorido

The presence of placental vascular anastomoses is a conditio sine qua non for the development of twin-to-twin transfusion syndrome (TTTS) and twin anemia ...

Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base for dental restorations. The current limitation of many reference scanners is the lack of accuracy scanning large objects like full dental arches, or the limited possibility to assess detailed tooth surfaces. A new reference scanner, based on focus variation scanning technique, was evaluated with regards to highest local and general accuracy. A specific scanning protocol was tested to scan original tooth surface from dental impressions. Also, different model materials were verified. The results showed a high scanning accuracy of the reference scanner with a mean deviation of 5.3 &#177; 1.1 &#181;m for trueness and 1.6 &#177; 0.6 &#181;m for precision in case of full arch scans. Current dental impression methods showed much higher deviations (trueness: 20.4 &#177; 2.2 &#181;m, precision: 12.5 &#177; 2.5 &#181;m) than the internal scanning accuracy of the reference scanner. Smaller objects like single tooth surface can be scanned with an even higher accuracy, enabling the system to assess erosive and abrasive tooth surface loss. The reference scanner can be used to measure differences for a lot of dental research fields. The different magnification levels combined with a high local and general accuracy can be used to assess changes of single teeth or restorations up to full arch changes.

Accuracy is a major demand in dental medicine. To verify accuracy, reference scanners are needed. This article presents a new reference scanner with an adjusted scanning method to acquire a broad variety of dental morphologies with high trueness and precision.

Precisão em Medicina Dentária, uma maneira nova de medir justeza e precisão

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base ...

A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to atherosclerotic plaque development or the rupturing of established plaques, interrupts normal blood flow leading to various morbidities such as myocardial infarction and stroke. In the clinic endovascular procedures such as angioplasty are commonly performed to reopen the lumen. However, these treatments inevitably damage the vessel wall as well as the vascular endothelium, triggering an excessive healing response and the development of a neointimal plaque that extends into the lumen causing vessel restenosis (re-narrowing). Restenosis remains a major cause of failure of endovascular treatments for atherosclerosis. Thus, preclinical animal models of restenosis are vitally important for investigating the pathophysiological mechanisms as well as translational approaches to vascular interventions. Among several murine experimental models, femoral artery wire injury is widely accepted as the most suitable for studies of post-angioplasty restenosis because it closely resembles the angioplasty procedure that injures both endothelium and vessel wall. However, many researchers have difficulty utilizing this model due to its high degree of technical difficulty. This is primarily because a metal wire needs to be inserted into the femoral artery, which is approximately three times thinner than the wire, to generate sufficient injury to induce prominent neointima. Here, we describe the essential surgical details to effectively overcome the major technical difficulties of this model. By following the presented procedures, performing the mouse femoral artery wire injury becomes easier. Once familiarized, the whole procedure can be completed within 20 min.

The mouse femoral artery wire injury model of restenosis is technically challenging. In this protocol we show the key technical details essential for successfully performing wire injury to induce consistent&#160;neointima for studies of restenosis.

Um modelo murino de Arterial Restenosis: Aspectos Técnicos do Femoral Injury Fio

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to ...

Induction of Accelerated Atherosclerosis in Mice: The "Wire-Injury" Model

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. Moreover, by rupture of the defective vascular wall, atherosclerosis induces occlusive thrombus formation, which represents the main cause of myocardial infarction or stroke and the most frequent cause of death. Despite the advances in the cardiovascular field, many questions remain unanswered, and additional basic research is essential to improve our understanding of the molecular mechanisms during atherosclerosis and its effects. Due to limited clinical studies, there is a need for representative animal models recreating atherosclerotic conditions such as neointima formation after stent implantation, balloon angioplasty, or endarterectomy. Since the mouse presents many advantages and is the most frequently used model for studying molecular processes, the current study proposes an invasive procedure of endothelial denudation, also known as the wire-injury model, which is representative of the human condition of neointima formation in arteries after revascularization procedures.

Induction of Accelerated Atherosclerosis in Mice: The &quot;Wire-Injury&quot; Model

This study describes an invasive procedure for the induction of accelerated atherosclerosis in mice. In comparison to other methods using electric- or cryo-induced injury, mechanical-induced injury mimics the human condition of restenosis after revascularization therapies and is ideal for the study of the molecular mechanisms involved.

Indução de Aterosclerose Acelerada em Camundongos: O Modelo de "Lesão por Fio"

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. ...

Shunt Surgery, Right Heart Catheterization, and Vascular Morphometry in a Rat Model for Flow-induced Pulmonary Arterial Hypertension

In this protocol, PAH is induced by combining a 60 mg/kg monocrotalin (MCT) injection with increased pulmonary blood flow through an aorto-caval shunt (MCT+Flow). The shunt is created by inserting an 18-G needle from the abdominal aorta into the adjacent caval vein. Increased pulmonary flow has been demonstrated as an essential trigger for a severe form of PAH with distinct phases of disease progression, characterized by early medial hypertrophy followed by neointimal lesions and the progressive occlusion of the small pulmonary vessels. To measure the right heart and pulmonary hemodynamics in this model, right heart catheterization is performed by inserting a rigid cannula containing a flexible ball-tip catheter via the right jugular vein into the right ventricle. The catheter is then advanced into the main and the more distal pulmonary arteries. The histopathology of the pulmonary vasculature is assessed qualitatively, by scoring the pre- and intra-acinar vessels on the degree of muscularization and the presence of a neointima, and quantitatively, by measuring the wall thickness, the wall-lumen ratios, and the occlusion score.

This protocol describes a surgical procedure to create a model for flow-induced pulmonary arterial hypertension (PAH) in rats and the procedures to analyze the principle hemodynamic and histological end-points in this model.

A cirurgia de derivação, coração direito Cateterismo e Vascular morfometria em um modelo de rato para induzida Fluxo de Hipertensão Arterial Pulmonar

In this protocol, PAH is induced by combining a 60 mg/kg monocrotalin (MCT) injection with increased pulmonary blood flow through an aorto-caval shunt ...

Model Surgical Training: Skills Acquisition in Fetoscopic Laser Photocoagulation of Monochorionic Diamniotic Twin Placenta Using Realistic Simulators

Fetoscopic laser coagulation of arterio-venous anastomoses (AVA) in a monochorionic placenta is the standard of care for twin-twin transfusion syndrome (TTTS), but is technically challenging and can lead to significant complications. Acquiring and maintaining the necessary surgical skills require consistent practice, a critical caseload, and time. Training on realistic surgical simulators can potentially shorten this steep learning curve and enables several proceduralists to acquire procedure-specific skills simultaneously. Here we describe realistic simulators designed to allow the user familiarity with the equipment and specific steps required in the surgical treatment of TTTS, including fetoscopic handling, approaches to anterior and posterior placenta, recognition of anastomoses, and efficient coagulation of vessels. We describe the skills that are especially important in conducting placental laser coagulation that the surgeon can practice on the model and apply in a clinical case. These models can be adapted easily depending on the availability of materials and require standard fetoscopy equipment. Such training systems are complementary to traditional surgical apprenticeships and can be useful aids for fetal medicine units that provide this clinical service.

Practicing the specific skills required for fetoscopic laser coagulation of monochorionic placental anastomoses on realistic models can aid less experienced surgeons in overcoming the steep learning curve associated with this procedure that is now regarded as the standard of care for twin-twin transfusion syndrome.

Modelo de Treinamento Cirúrgico: Aquisição de Competências em Fotocoagulação Fetoscópica a Laser de Placenta Gêmea Diamniótica Monocoriônica Utilizando Simuladores Realistas

Fetoscopic laser coagulation of arterio-venous anastomoses (AVA) in a monochorionic placenta is the standard of care for twin-twin transfusion syndrome ...

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

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

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

Indução de síndrome nefrótica em camundongos por injeção Retrobulbar de doxorrubicina e na prevenção da retenção de Volume por liberação sustentada aprotinina

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

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty (PVP)

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The accuracy of PVP mainly depends on the surgeons&#39; experience and multiple fluoroscopes during a traditional procedure. Puncture related complications were reported all over the world. To make the surgical procedure more precise and decrease the rate of puncture-related complications, our team applied a three-dimensional printing guide template to PVP to modify the traditional procedure. This protocol introduces how to model target vertebrae DICOM imaging data into three-dimensions in the software, how to simulate operation in this 3-D model, and how to use all of the surgical data to reconstruct a patient specific template for application. Using this template, surgeons can identify suitable puncture points accurately to improve the accuracy of the operation. The whole protocol includes: 1) diagnosis of the osteoporotic vertebral compression fracture; 2) acquisition of CT imaging of the target vertebra; 3) simulation of the operation in the software; 4) design and fabrication of the 3-D printing guide template; and 5) application of the template into an operation procedure.

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty PVP

Herein, we present a three-dimensional printing guide template for percutaneous vertebraplasty. A patient with a T11 vertebral compression fracture was selected as a case study.

Modelo de guia de impressão tridimensional assistida Vertebroplastia Percutânea (PVP)

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The ...

OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery

The use of in vitro maturation (IVM) before gynecological operation (OP-IVM) is an extension of conventional IVM that combines IVM following oocyte retrieval with routine gynecological surgery. OP-IVM is suitable for patients undergoing benign gynecological surgery who have the need for fertility preservation (FP) or infertility treatments such as in vitro fertilization and embryo transfer (IVF-ET). In the operating room, patients undergoing benign gynecological surgery are first anesthetized and receive ultrasound-guided immature follicle aspiration (IMFA) treatment. As the subsequent gynecological surgery is performed, the cumulus-oocyte complexes (COCs) are examined, and the immature COCs are transferred into the IVM medium and cultured for 28-32 hours in the IVF laboratory. After assessment, mature oocytes in the MII stage will be selected and cryopreserved in liquid nitrogen for FP or fertilized by intracytoplasmic sperm injection (ICSI) for IVF-ET. By combining IVM with gynecological surgery, immature oocytes that would have been discarded can be saved and used for assisted reproductive technology (ART). The procedure, significance and critical aspects of OP-IVM are described in this article.

In vitro maturation (IVM) before gynecological operation (OP-IVM) combines IVM following oocyte retrieval with routine gynecological surgery and serves as an extension of conventional IVM applications for fertility preservation.

OP-IVM: Combinando Maturação In vitro após Recuperação de Oócito com Cirurgia Ginecológica

The use of in vitro maturation (IVM) before gynecological operation (OP-IVM) is an extension of conventional IVM that combines IVM following oocyte ...