Collection: Sinusitis

It is as simple as that! When the inflammation extends beyond the nasal cavities (about 5-7 days after what we can classify as a common cold), the same inflammation is also beginning to affect the mucosa lining the ostia of the paranasal sinuses (small 1-2 mm diameter ducts that connect the nasal passages to the paranasal sinuses). When it becomes inflamed, the mucosa increases in volume: because the ostia are very narrow, it results in the narrowing of their internal lumen until they become occluded. When the ostium of a paranasal sinus is occluded, two very important functions of the latter are altered, namely: stopping the flow of mucus from the paranasal sinuses to the sinus cavities of the nose (thus outward) and, most importantly, preventing the transit of oxygen from the nose to the paranasal sinuses. Stopping the transit of oxygen in the sinuses, in fact, results in the onset of neuropathic pain, or inflammation of the craniofacial nerves.

When an ostium is occluded, the paranasal sinus connected to it takes on the appearance of an air-filled balloon closed at the end. The walls of the paranasal sinus are not impermeable to air as they are lined with ciliated mucosa in which blood vessels are present: these vessels will more or less quickly absorb oxygen trapped in the sinus.

When it has been completely absorbed, a depression forms inside the sinus. This generates a physical force that pulls the mucosa toward the center of the paranasal cavity, as if it were detaching from the bone to which it is anchored. It is the same phenomenon that occurs when air is forcefully expelled from a balloon and its walls tend to collapse against each other.

Obviously, the mucosa does not only consist of hair cells, mucipar cells, blood vessels etc. but also of nerve fibers connected to craniofacial nerves. Therefore, when there is the establishment of depression i.e., negative pressure from the outside to the inside, there is a mechanical stress on the nerve fibers that is transmitted and reflected on the craniofacial nerves and from which pain originates.

Moreover, if the situation of complete obstruction of the ostium remains unchanged, as soon as the trapped oxygen is completely depleted, a new process intended to increase pain: the mucosa lining the sinuses will begin to produce a large amount of mucus that evidently cannot exit the affected sinus due to obstruction of the ostium. The mucus itself, then, will eventually exert positive pressure against the mucosa lining the breast (i.e., outward), putting more stress on the nerve fibers and accentuating the pain.

Although what has been highlighted so far summarizes a disastrous situation at the clinical level, the trouble is not over yet: should the situation of the obstruction of the ostium continue much longer, the mucus that has accumulated in the affected sinus, will become infected due to certain pathogenic bacteria that manage in various ways to enter the same sinus. The pain will be overlaid with infection and thus the need to take large amounts of antibiotics.