Biomedical Engineering Reference
In-Depth Information
in the near future. However, in a single case, a POSS-PCU bypass graft has already been
used as a femoral bypass graft in a patient and he is currently being monitored to evaluate
the outcome of the bypass.
Lastly, we have utilized POSS-PCU for patient use as a lacrimal duct conduit (LDC)
(Figure 21.2). Patients suffering from extensive tearing, blurry vision, and infections have
an obstructed lacrimal drainage system [70]. The obstruction can be at different levels of
the drainage apparatus [70]. When it is at the canalicular level, the standard treatment of
stenting or reopening the obstruction fails [70]. Therefore the placement of a bypass is
often the only treatment option [70]. This is done by the insertion of a polyurethane tube
to allow tears to flow into the nose [70]. However, this damages normal tissue and function,
including mucous blockage, and the tube may become dislocated causing a source of com-
plications [70]. Owing to the viscoelastic and biocompatibility properties of POSS-PCU a
small diameter conduit was made to replace the canaliculus and overcome lacrimal duct
obstruction [70].
The Ethics of Nanotechnology in Regenerative Medicine
We have illustrated with various nanomaterials the tremendous potential that nanotechnology
could contribute to the improvement in health care. Nanotechnology deals with particles that
are dominated by forces of physics and chemistry that are not present in traditional materials
[71]. This unique and novel behavior can be exploited and manipulated by scientists for tissue
engineering. However, understanding of this full potential will not be accomplished until the
social and ethical issues are delineated. In general, as nanotechnology is a relatively new
technology there are still ethical concerns about consumer and occupational safety and health.
The key concern will be ensuring that medical nanodevices are classified appropriately for
clinical use [72]. A new “drug” must demonstrate safety and efficacy using a multistep
approval process before regulatory approval, often taking years to complete [72]. However,
the premarket approval for a medical “device” is much less rigorous and for “cosmetic” use
the FDA does not have a premarket approval system.
Hence, labeling the nanodevice as a “drug” or “device” or “cosmetic” will prove to be vital
to ensuring patient safety [72].
As nanotechnology will be used for many things other than medicine, there is concern
that there will be an effect on the environment and nature. Further research is required to
fully understand the impact of the accumulation of nanoparticles in plants and microorgan-
isms to fully appreciate the extent on the environment [73]. It is important to remember that
whether toxic hazardous materials will be released into the environment during the manu-
facture of the use of nanoproducts is still not known [73].
Lastly the main ethical debate is where the use of nanotechnology will be utilized to alter
our human function rather than only restoring human function from disease and injury [74].
Currently there is a spectrum of beliefs, at one end people will argue to embrace new
technology to advance our health but others will feel we should recognize the dangers and
brake further technological development [74, 75].
Translating Science to Product
Nanotechnology will improve the quality of life of patients, extend life expectancies, and
reduce overall health costs. However, the clinical translation of regenerative medicine
requires more than scientific discovery.
