Visualization of the microcirculation of the nasal mucosa in vivo in different nasal disorders, using Sidestream Dark Field (SDF) imaging

The nose, and in particular the nasal mucosa, is a very dynamic organ system.
It combines olfactory and respiratory functions and acts as a first defence
mechanism against pathogens. The nose maintains a rich neurovascular network
to manage the different tasks of which the nasal microcirculation stands out in
managing these very diverse physiological processes. However, little is known
about abnormalities of the microcirculation and the role it may play in
different nasal dysfunctions or disorders.
The most common disorder is the common cold, caused by a viral infection.
Unlike this common cold, which is self-limiting, about 20% of the population
suffers from chronic rhinitis. Chronic rhinitis can be divided into allergic
rhinitis, infectious and non-allergic, non-infectious rhinitis. The latter is
called idiopathic rhinitis and diagnosis is made by exclusion of specific
causes such as, for example, medication usage, smoking or hormonal.
Other chronic disorders in ENT medicine comprise chronic rhino sinusitis and
nasal polyps; by some classified as belonging to the same range of disorders.
The precise cause is still unknown and most patients present with a combination
of the two disorders.
Often underestimated, but the above described, chronic disorders can impair
quality of life in a great deal. It can contribute to sleep disorders, social
or emotional problems, school or work functioning, and not to mention the
financial consequences it has for society. Besides that, many patients respond
differently, or do not respond at all to therapy. Because of the complexity of
complex disorders, it is sometimes difficult to set the right diagnosis and
therapy. It has been suggested that quantitative and qualitative differences in
the nasal microvasculature may be detected amongst the above-described
disorders.
Most of the methods used to study the microcirculation in nasal dysfunction
rely on immunohistochemistry. Up until now, the methods used to visualize the
microcirculation in vivo in nasal mucosa are laser Doppler flowmetry and
rhinostereometry.
In the present study, the microcirculation of the nasal mucosa will be analysed
with a relatively new technique, called SDF imaging (Microscan, Microvision
Medical, Amsterdam), an improved version of OPS imaging. It is a hand held
microscope, emitting green light, which can be used to observe the
microcirculation in great detail. It has been used and is being used in a
number of clinical studies in the AMC currently. With this technique, different
factors of the microcirculation can be visualized and differences among groups
can be compared. It is the first time that the microcirculation of nasal mucosa
is visualized in vivo with SDF imaging. As such, we propose that this approach
will lead to a better understanding of the pathophysological mechanisms
operative in nasal dysfunction. It may help us to differentiate between
aetiology of different disorders and may clear out why some people react well
to medication while others do not (anymore).

To assess the normal nasal microcirculation in vivo. Also, this research may
lead to a better understanding of the pathophysological mechanisms operative in
nasal dysfunction. It may help us to differentiate between aetiology of
different disorders and may clear out why some people react well to medication
while others do not (anymore).

single center pilot study

The technique used is non-invasive. The presence of the probe in the nasal
cavity can give an inconvenient experience. If possible, this will be avoided.
The usage of the SDF imaging device is harmless and this research has not
impact on further treatment.