What is Sphenoid Sinusitis, Know its Causes, Symptoms, Treatment, Prognosis, Pathophysiology

Sphenoid sinusitis is a medical condition in which the sphenoid sinus of the individual accumulates a large amount of mucoidal secretions owing to sinusoidal infection due to bacteria, fungus or virus invasion. The site of infection lies behind the eyes within the skull.

Sinus is an air filled cavity present on both the sides of the nasal cavity. The purpose of these cavities is to filter the air inhaled with the help of the internal lining of the mucus. There are four sinuses present around the nasal cavity and the sinus which is present at the back of the head, behind the eye, is called the sphenoid sinus.

When the sphenoid sinus gets infected, internal mucus lining gets inflamed and causes the accumulation of mucus and pus within the sinus, leading to the obstruction of the nasal cavity and resulting in sphenoid sinusitis. This obstruction leads to increase of pressure, resulting in pain around the eyes, ears and headaches.

The primary causative factor behind the sphenoid sinusitis is the presence of the bacterial infection within the sphenoid sinus. The bacterium responsible for the infection and inflammation is Streptococcus pneumonia. The other causative agent apart from the bacteria is the viral infection of sinus due to Haemophilus influenza. These microbes cause the excessive secretion of mucus within the sinus and block the nasal cavity.

The symptoms that identify the condition of Sphenoid Sinusitis are:

• Continuous running nose
• Headache, especially around the cheekbones and the posterior nasal region is a symptom of Sphenoid Sinusitis.
• Blockage in the nose
• Pressure sense in and around the cheekbones and the nose
• Fever
• Respiratory tract infections can also be a symptom of sphenoid sinusitis
• Feeling of uneasiness
• Sneezing and throat pain
• Pain the teeth
• Swollen eyes with constant watering
• Nasal Bleeding.

Sphenoid sinusitis is most rare amongst all kinds of sinusitis, with as low as around three percent of total sinusitis incidences.

The pathophysiology behind sphenoid sinusitis is the existence of negative pressure within the sinus due to increase in the levels of oxygen in the blood vessels adjacent to the mucus lining of the sinus. The presence of viral or bacterial upper respiratory tract infection causes inflammation as well as accumulation of transudate, which is a fluid oozed out by the adjacent blood vessels due to the negative pressure. On the other hand, development of positive pressure on the blood vessels causes swelling and pain, which is known as the sphenoid sinusitis.

The treatments available for the condition are both surgical as well as non-surgical.

• Non-surgical Measures for Treating Sphenoid Sinusitis: These measures include administration of nasal decongestants, nasal sprays, steam inhalation, nasal glucocorticoids, mild analgesics and oral antibiotics like amoxicillin.
• Surgical Measures to Treat Sphenoid Sinusitis: When non-surgical measures fail to provide the required relief, then the final resort is the surgery. This is done in the case of chronic sinusitis. The surgery helps in reducing the blockage of the sinus and help in effective drainage of the secretions.

The outlook for sphenoid sinusitis is quite good, when the condition is addressed and treated with antibiotics within a span of a month. This reduces the risk of complications else severe complications can result in abscess formation in the brain and cranial nerve as well as meningitis.

The risk factors that pose a threat for sphenoid sinusitis are:

• Upper Respiratory Tract Infection: The upper respiratory tract infection is the most common threat to the onset of sphenoid sinusitis, because its common symptoms are inflammation and swelling within the sinus.
• Tooth Abscess: The pus production as result of abscessed tooth can cause internal infection in the sphenoid sinus. The abscess of molar teeth has the greatest risk of all.
• Allergy as a Risk Factor of Sphenoid Sinusitis: Some individuals have recurrent allergy attacks owing to allergens like dust pollen, etc. This can further result in inflammation and swelling of the sinus and cause sinusitis as well as sphenoid sinusitis.
• Nasal Passage Structural Defects Leading to Sphenoid Sinusitis: The presence of structural abnormalities within the nasal passage like deviated septum can cause blockage of nasal cavity and result in improper drainage of mucus, leading to sinusitis.
• Nasal Polyps: These certain tissues that grow abnormally within the nasal region. These are quite common and have several complications like sphenoid sinusitis.
• Enlargement of Adenoids: Adenoids are present in the throat right behind the nose. These are a mass of soft tissues which when inflame and swell, due to infection, can spread the infection to the sphenoid sinus.
• Weak Immunity: Individuals with weak immune system cannot fight infections giving way to opportunistic microbes and result in several infections like sphenoid sinusitis and many others.

The potential complications of sphenoid sinusitis are:

• Protrusion of eyes
• Cavernous sinus thrombosis in which the cavernous sinus cavity that drains the deoxygenated blood out of the brain undergoes blood clotting
• Periorbital cellulitis or inflammation of eyelids and skin or the adjoining areas of skin around the eyes
• Osteomyelitis or bone infection of the bones of nasal cavity
• Formation of tumor within the sinus, which may further spread to cavernous sinus.

The diagnosis of sphenoid sinusitis is mostly based on the assessment of the history and the symptoms; but in case of severe complication, imaging tests are also conducted.

• Assessment of Medical History: This assessment involves ruling out the possibility of conditions like viral infections, bacterial sinusitis, allergic rhinitis and acute sinusitis.
• Physical Examination: It involves analysis of the head and the neck region to check for the symptoms of sphenoid sinusitis. It is usually done post the administration of nasal decongestant.
• Endoscopic Analysis: In the endoscopic analysis, an optical tube is pushed up through the nose to get a better view of the internal condition. In some cases, endoscopy is also used for obtaining sample for culture of the sinus secretions and they are studied for diagnosis.
• Analysis through Imaging: The imaging techniques used for the diagnosis of sphenoid sinusitis is CT scan and X-ray. These are done to get a better picture of the nasal cavity. CT scan is preferred over X-rays in most cases.

Sphenoid sinusitis is commonly misdiagnosed owing to the symptoms which are quite similar to common cold. The condition is often misdiagnosed by less experienced professionals and hence one must consult an experienced physician.

The common preventive measures that can be followed are:

• Refraining from active as well as passive smoking
• Avoiding drying of nasal passage by using humidifiers and nasal sprays
• Keeping nasal sprays handy in case one is prone to allergies.

Sphenoid sinusitis or sphenoiditis is the infection of the sphenoid sinus caused by bacteria or virus. It further results in inflammation of the inner lining of the sinus, leading to accumulation of mucus. This majorly blocks the nasal passage and results in headache, pain in ears and eyes. Though the condition is less common but if not addressed appropriately and in time, it can result in several serious complications.