Avtor/Urednik		Yamakado, Koichiro; Pavčnik, Dušan; Uchida, Barry T; Timmermans, Hans; Corless, Christopher L; Park, Joong Wha; Yamada, Katsuyuki; Keller, Frederic S; Roesch, Josef
Naslov		Biliary small intestinal submucosa covered Z-stents: preliminary results in an animal model
Prevedeni naslov		Stenti Z, oplaščeni s submukozo tankega črevesa v žolčnem sistemu: rezultati preliminarne raziskave na živalskem modelu
Tip		članek
Vir		Radiol Oncol
Vol. in št.		Letnik 35, št. 1
Leto izdaje		2001
Obseg		str. 1-10
Jezik		eng
Abstrakt		Background. Purpose of the study was to test the function and biological response of metallic stents covered with small intestinal submucosa (SIS) in the swine biliary system. Materials and methods. A total of 9 SIS-covered single Z-stents were placed in the common bile duct (CBD) in 6 pigs. Stents were delivered into the CBD at laparotomy via the gall bladder and the cystic duct. Animals were sacrificed or died at 2 weeks (n=1), 4 weeks (n=1), 8 weeks (n=2), and 10 weeks (n=2) after stenting and histological studies were performed. Results. Nine stents were deployed in 6 animals. During follow-up, 3 stents in 3 animals (2, 4, and 10 weeks) remained stable, while one stent shifted distally in CBD and 5 of them turned sideways. All stents remained patent. Duct dilatation and bile slugging were noted at 10 weeks. The SIS-membrane was present at 2 weeks, but was not histologically distinct at 4 weeks and later. Histological study showed no significant inflammatory changes in the bile duct in any pig. Mucosal hyperplasia was absent in 2 of 3 stable stents at 2 and 10 weeks, and 1 distally shifted stent at 10 weeks. Mild mucosal hyperplasia was seen at the distal stent end in 1 stable stent at 4 weeks and in 5 dislodged stents at 8 and 10 weeks. Conclusions. Even when the study is limited by dislodgment of high percentage of placed stents, the results in stable stents conducting the bile flow suggest that SIS helps to prevent bile duct inflammation and mucosal hyperplasia typical for uncoated stents. Further studies, particularly with improved wet SIS are warranted.
Izvleček		Z raziskavo na svinjah smo testirali uporabnost in biološki odgovor kovinskih stentov v žolčnem sistemu, oplaščenih z submukozo tankega črevesja (SIS). Materiali in metode. V skupni žolčevod 6 svinj smo vstavili 9 enojnih stentov Z, oplaščenih s submukozo tankega črevesa. Stente smo vstavili z laparatomijo skozi žolčni mehur in žolčnikov vod. Živali smo žrtvovali ali usmrtili 2 tedna (n=1), 4 tedne (n=2) in 10 tednov (n=2) po vstavitvi stentov. Hkrati smo izvedli tudi histološke preiskave. Rezultati. Šestim živalim smo vgradili 9 stentov. Med pregledi po 2, 4 in 10 tednih so 3 stenti v 3 živalih ostali na svojem mestu, medtem ko se je 1 v skupnem žolčniku distalno premaknil, 5 pa se jih je obrnilo postrani. Vseh 9 stentov je bilo prehodnih. Po 10 tednih smo opazili, da se je žolčevod razširil, pretakanje žolča pa se je upočasnilo. Submukoza v tankem črevesju je ostala tudi po dveh tednih in se niti po 4 tednih niti kasneje ni histološko spremenila. Histološka preiskava ni odkrila nobenih vnetnih sprememb v žolčevodih preizkusnih živali. V 2 do 3 nepremaknjenih stentov niti po 2 niti po 10 tednih nismo opazili hiperplazije mukoze, v enem distalno premaknjenem stentu pa se je pojavila po 10 tednih. Zmerno hiperplazijo mukoze smo po 4 tednih opazili na distalnem delu nepremaknjenega stenta in po 8 in 10 tednih pri 5 premaknjenih stentih. Zaključek. Četudi je zaradi visokega odstotka premaknjenih stentov raziskava omejena, so rezultati nepremaknjenih stentov, ki urejajo pretok žolča, potrjujeo, da stenti v tankem črevesju, oplaščeni s submukozo preprečujejo vnetje žolčevoda in hiperplazijo mukoze, ki sta pogosti pri neoplaščenih stentih. Raziskave bomo nadaljevali in jih še posebej izboljšali na stentih z ovlaženo submukozo tankega črevesa.
Deskriptorji		BILE DUCTS INTESTINAL MUCOSA STENTS SWINE BILIARY TRACT SURGERY CHOLANGIOGRAPHY