What Is Acute Frontal Sinusitis?
Acute frontal sinusitis is a serious disease that, if not managed appropriately, can lead to serious complications. Frontal sinusitis can easily spread to the eye and the brain due to its proximity.
Primarily seen in adolescent males and young men, acute frontal sinusitis is inflammation and swelling of the frontal sinus present in the frontal bone (bone-forming the forehead). A sinus is an air-filled cavity lined with mucus present inside the bone; it has an opening called the ostium, through which it drains into the nose. The body has four pairs of nasal sinuses-
Frontal Sinuses - Found above the eyes in the forehead.
Ethmoidal Sinuses - Present between the eyes, in the anterior bridge of the nose.
Maxillary Sinuses - Located below the eyes in the maxilla (upper jaw) on either side.
Sphenoidal Sinuses - Are found at the back of the eyes in the sphenoid bone.
All the sinuses are inter-connected and drain into the nose through their respective openings; they humidify the incoming air and prevent the body from infections through cell-mediated immunity. Frontal sinusitis occurs when it becomes infected (bacteria, virus, or fungus). The infection triggers an immune reaction causing inflammation and excess mucus production; this, in turn, blocks the ostium preventing the drainage into the nose.
What Causes Acute Frontal Sinusitis?
The occurrence of frontal sinusitis alone without involving other sinuses is rare; it mostly occurs in conjunction with the ethmoid sinus and is caused due to an antigen (bacteria, virus, or fungus). In a healthy individual, the body has in-built immunity to fight off the antigen. Still, in patients with associated risk factors, the infection persists and causes severe symptoms that reduce the quality of life. The associated risk factors are:
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Anatomic defects like septum deviation.
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Immunodeficiency in individuals with HIV, diabetes, hypertension, etc.
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Nasal polyposis (soft tissue growth inside the nose obstructs sinus drainage).
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Environmental factors like passive smoking and polluted air.
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Allergies and cystic fibrosis.
Apart from the risk factors mentioned above, developmental defects in the ethmoid bone also affect the sinus flow of the frontal bone because, from an embryological point of view, the frontal sinus develops from the pneumatization (formation of air bubbles) of the ethmoid bone; hence any faults in the ethmoid will lead to defects in the frontal sinus outflow.
What Are the Symptoms of Acute Frontal Sinusitis?
The symptoms of frontal sinusitis are similar to that of regular sinusitis; the severity of the symptoms may vary depending on the duration of the infection; they are:
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Facial pain, pressure, and fullness.
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Nasal obstruction and nasal discharge.
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Fever, headache, and malaise.
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Cough and phlegm in the spit.
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Bad taste in the mouth and bad breath.
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Loss of smell and insomnia.
Ideally speaking, frontal sinusitis is considered acute when the symptoms are persistent after three weeks from the onset. However, there have been cases where the infection spread to the brain, causing bacterial meningitis in just ten days.
What Is the Treatment for Acute Frontal Sinusitis?
Due to its close relation to vital organs, frontal sinusitis may lead to dangerous complications like meningitis, brain abscess, sinus thrombosis, blindness, etc.; the clinician will prescribe medication (intravenous antibiotics, nonsteroidal anti-inflammatories, nasal decongestants, and corticosteroids) after initial diagnosis which gets rid of the infection and reduces the symptoms in most of the patients.
In a few patients with debilitating conditions, the symptoms persist and often worsen, needing surgery to drain the sinus. The surgery to drain the frontal sinus is known as frontal sinusotomy; two approaches can do it as mentioned below:
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Functional Endoscopic Sinus Surgery (FESS) - It has become the go-to approach for surgeons for the past 20 years. It is effective for difficult sinus pathologies and when multiple sinuses need to be taken care simultaneously. It is advantageous compared to the external approach due to its invisible scarring and preservation of undamaged bone.
Technique - After anesthesia, the surgeon places the endoscope (illuminated tube with a camera) inside the nose and locates the frontal sinus ostium (sinus opening); a variety of instruments are used to drain the sinus, followed by nasal packing.Care is taken not to disturb the healthy tissue; this will aid in the formation of new tissue. In a few complicated cases, the surgeon will use a frontal sinus stent to facilitate irrigation and drainage post-op.
If adjacent structures are also infected, the surgeon might perform an uncinectomy (removal of the uncinate process of the ethmoid) or frontoethmoidectomy (removal of infected ethmoid and frontal bone). Occasionally a transblepharoplasty (removal of the superior orbital rim to access the frontal sinus) can also be performed depending on the structures infected; all these procedures are done to facilitate sinus drainage.
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External Approach - This is done in patients with a previous failed FESS, osteomyelitis, or trauma. After anesthesia, an incision is made in the eyebrow below the orbital rim, the underlying tissue is elevated, and the frontal sinus is accessed with a drill or a chisel. The sinus is drained, and catheters are inserted for post-operative irrigation and drainage. The skin is sutured back around the catheter.
Although the underlying concept remains the same, an external approach can be made by trephination, Lynch procedure, Lothrop procedure, or by using an osteoplastic flap with obliteration of the frontal sinus.
The surgeon chooses the approach after careful evaluation and proper investigations. A computed tomography (CT) scan or magnetic resonance imaging (MRI) is recommended based on the condition. The goal of the procedure is to remove the infected tissue and bone and facilitate drainage by enlarging the ostium.
What Happens After Surgery?
Once the anesthesia wears off, the patient is checked for vitals and closely monitored for complications. Oral antibiotics are prescribed to eliminate a residual infection, and nasal decongestants relieve congestion. To rinse debris and mucus, saline irrigation with a neti pot is always recommended.
Post-operative care includes regular follow-ups for debridement (removal of blood clots and crusts) and checking the frontal sinus's patency. If a stent is placed, it is usually removed after one to eight weeks.
What Are the Complications of Frontal Sinusotomy?
Every surgical procedure carries risks to a certain extent; complications for a frontal sinusotomy are similar to that of any sinus surgery and include the following:
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Epistaxis (bleeding from the nose).
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Orbital ecchymosis (discoloration of the eye).
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Emphysema (shortness of breath).
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Diplopia (double vision).
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Blindness.
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Cerebrospinal fluid leakage.
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Intracranial injury followed by a brain stroke.
The patient is always recalled for post-surgery follow-up to check for any complications mentioned above and evaluate the prognosis.
Conclusion
The overall success of frontal sinusotomy depends on the severity of the infection, type of approach, and post-surgical follow-up. It is a well-tolerated procedure with a low recurrence rate. It is important to note that the management of acute frontal sinusitis cannot be done with surgery alone; maximum medical therapy (MMT) before the surgery and post-op plays an important role.
