Figure 9.7
192
Bacterial Cellulose
(a)
(b)
(c)
Figure 9.7
Scanning. electron. microscopy. (magnification. ×16–×19):. (a). untreated. segment. of. the. carotid.
artery,.(b,.c).good.endothelialization.of.bacterial.cellulose.grafts..Reprinted.with.permission.
from.Dieter.Schumann.et.al.,.Artificial.vascular.implants.from.bacterial.cellulose:.preliminary.
results.of.small.arterial.substitutes,.Cellulose.16:877–878.
After. 3.months,. seven.grafts.(87.5%).were.patent,.whereas.one.graft.was.
occluded..Scanning.electron.microscopy.revealed.complete.recellularization.
of.the.inner.surface.by.recipient.endothelial.cells.(Figure 9.7)..Light.microscopy.showed.a.three-layered.wall.structure.of.the.BNC.segments.with.the.
cellulose. still.being.present..These.data.demonstrate.the.potential.of.engineered. BNC. grafts. for. small-caliber. vessel. substitution.. As. the. innovative.
BNC.engineering.technique.can.provide.stable.small-caliber.vascular.conduits.of.any.desired.size.and.length,.it.offers.a.highly.attractive.approach.in.
cardiovascular.surgery..All.the.pigs.survived.after.surgery..In.summary,.the.
following.results.were.obtained:
•. Paraplegia.was.not.observed.in.any.animal.during.the.postoperative.period.
•. BNC. demonstrated. sufficient. surgical. properties. for. suturing. and.
handling.
•. Flow. was. restored. with. no. leaks. or. oozing. through. the. polymer.
after.the.anastomoses.were.completed.in.all.animals.
•. There.were.no.significant.differences.in.blood.flow.at.the.proximal.
and. distal. anastomoses. after. the. initial. implantation. (53.6. ±. 10. ml.
and.53.7.±.8.5.ml).
•. After. 3. months. a. capsule-like. tissue. formation. was. observed. in.
all.animals.
•. One.graft.was.found.collapsed.and.occluded,.perhaps.owing.to.the.
surrounding.tissue.
•. Seven.grafts.were.patent.(patency.rate.87.5%)..There.was.no.. stenosis.
observed. histologically. at. the. proximal. or. distal. anastomoses. in.
any.animal.
•. No.apparent.changes.in.the.graft,.including.dilatation,.dehiscence,.
or.aneurysmatic.enlargement.were.detected.
192
Bacterial Cellulose
(a)
(b)
(c)
Figure 9.7
Scanning. electron. microscopy. (magnification. ×16–×19):. (a). untreated. segment. of. the. carotid.
artery,.(b,.c).good.endothelialization.of.bacterial.cellulose.grafts..Reprinted.with.permission.
from.Dieter.Schumann.et.al.,.Artificial.vascular.implants.from.bacterial.cellulose:.preliminary.
results.of.small.arterial.substitutes,.Cellulose.16:877–878.
After. 3.months,. seven.grafts.(87.5%).were.patent,.whereas.one.graft.was.
occluded..Scanning.electron.microscopy.revealed.complete.recellularization.
of.the.inner.surface.by.recipient.endothelial.cells.(Figure 9.7)..Light.microscopy.showed.a.three-layered.wall.structure.of.the.BNC.segments.with.the.
cellulose. still.being.present..These.data.demonstrate.the.potential.of.engineered. BNC. grafts. for. small-caliber. vessel. substitution.. As. the. innovative.
BNC.engineering.technique.can.provide.stable.small-caliber.vascular.conduits.of.any.desired.size.and.length,.it.offers.a.highly.attractive.approach.in.
cardiovascular.surgery..All.the.pigs.survived.after.surgery..In.summary,.the.
following.results.were.obtained:
•. Paraplegia.was.not.observed.in.any.animal.during.the.postoperative.period.
•. BNC. demonstrated. sufficient. surgical. properties. for. suturing. and.
handling.
•. Flow. was. restored. with. no. leaks. or. oozing. through. the. polymer.
after.the.anastomoses.were.completed.in.all.animals.
•. There.were.no.significant.differences.in.blood.flow.at.the.proximal.
and. distal. anastomoses. after. the. initial. implantation. (53.6. ±. 10. ml.
and.53.7.±.8.5.ml).
•. After. 3. months. a. capsule-like. tissue. formation. was. observed. in.
all.animals.
•. One.graft.was.found.collapsed.and.occluded,.perhaps.owing.to.the.
surrounding.tissue.
•. Seven.grafts.were.patent.(patency.rate.87.5%)..There.was.no.. stenosis.
observed. histologically. at. the. proximal. or. distal. anastomoses. in.
any.animal.
•. No.apparent.changes.in.the.graft,.including.dilatation,.dehiscence,.
or.aneurysmatic.enlargement.were.detected.