sinuses

Description

Sinuses  are referred to those hollow , air-filled cavities that are in the skull and connected to the nasal airway by a narrow hole in the bone (ostium). 

 Humans have four pair of these cavities which are often described as a unit and termed the "paranasal sinuses" .

These  four pair of sinuses are  named according to the bones within which the sinuses lie:

1. frontal sinus (in forehead) in the frontal bone .
2. maxillary sinus (behind cheeks) 

         also called the maxillary antra .It's the largest of the paranasal sinuses,  in the  maxillary bones,.

    3. ethmoid sinus (between the eyes) formed from several discrete air cells within the ethmoid bone.

    4. sphenoid sinus (deep behind the ethmoids) in the sphenoid bone at the center of the skull base under the pituitary gland.

The paranasal air sinuses are lined with mucus-secreting cells, epithelial cells and some cells that are part of the immune system (macrophages, lymphocytes, and eosinophils).


Functions of the sinuses

• Decreasing the relative weight of the front of the skull, and especially the bones of the face.
• Increasing resonance of the voice.
• Providing a buffer againt facial trauma.
• Insulation of sensitive structures like dental roots , nerves and eyes from rapid temperature fluctuations in the nasal cavity.
• Humidifying and heating of inhaled air because of slow air turnover in this region.

 Sinusitis

It's the inflammation of one or more of the paranasal sinuses and nasal passages.
 This is may be due to :
.  A pathogenic organism (virus, bacterium, or a fungus) grows within a sinus .
The sinuses contain defenses against foreign bacteria (germs). If a disruption occurs that affects the normal host defenses inside the sinuses, those defenses may allow bacteria, which are normally present in the nasal passages, to enter any of the sinuses. Once there, the bacteria may stick to the lining cells and cause a sinus infection.
.  Allergy and irritation of the sinuses such as with hay fever.
.  Irritants, such as chemicals .
. The use and/or abuse of over-the-counter (OTC) nasal sprays.
.  Illegal substances that may be snorted through the nose.

these factors cause intermittent blockage of the sinus ostium (a small orifices joined to the nasal cavity).
 If this happens, normal drainage of mucus within the sinuses is disrupted. Drainage of mucus and pus often occur when the blockage is relieved. The drainage usually goes from the nasal passages to the throat or out the nostrils.


Symptoms of sinusitis

      .   headache.
     .   facial tenderness.
     .   pressure or pain in the eyes, nose, cheek area, or on one side of the head.
     .    fever (25% of patients may have fever associated with acute sinus infection).

• cloudy, discolored , thick nasal drainage .
  .
• a feeling of nasal stuffiness
• sore throat
• cough.

Some people notice an increased sensitivity or headache when they lean forward because of the additional pressure placed on the sinuses. Others may experience tooth or ear pain, fatigue, or bad breath.

 In noninfectious sinusitis, other associated allergy symptoms of itching eyes and sneezing may be common. Nasal drainage is usually clear or whitish-colored in people with noninfectious sinusitis.


 Sinusitis is categorized as :

1. Acute sinusitis  (sudden onset) usually lasts less than 8 weeks or occurs no more than 3 times per year with each episode lasting no longer than 10 days. Medications are usually effective against acute sinusitis. Successful treatment counteracts damage done to the mucous lining of the sinuses and surrounding bone of the skull.

2. Chronic sinusitis (long term, the most common type) lasts longer than 8 weeks or occurs more than 4 times per year with symptoms usually lasting more than 20 days.



Treatment of sinusitis

.   For sinusitis caused by virus infection, no antibiotic treatment is required.
.   For sinusitis caused by bacterial infection ,Antibiotics are not helpful for patients with mild-to-moderate symptoms, so they should not be prescribed for at least the first 7 days.

 If the symptoms lasts for more than 7 days amoxicillin-clavulanate (Augmentin) is the first-line drug for treatment of a suspected bacterial sinus infection .
-(The five most common bacteria causing sinus infections are Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Streptococcus pyogenes).
-In the penicillin allergic individual, cefaclor (Ceclor), loracarbef (Lorabid), clarithromycin (Biaxin), azithromycin (Zithromax), sulfamethoxazole (Gantanol), trimethoprim (Bactrim, Septra).
An effective antibiotic needs to be continued for a minimum of 10-14 days.

.   Saline nasal irrigation is often needed on an ongoing basis.

.  Decongestants as  pseudoephedrine.

.  Mucolytics as guaifenesin and  expectorants.

.   Antihistamines should be avoided unless it is felt that the sinusitis sinus infection is due to allergy, such as  from pollens, dander, or other environmental causes.

.  Topical nasal steroid spray  such as prednisone will help reduce swelling in the allergic individual without the drying that is caused by using antihistamines although both are occasionally used.

In many people, allergic sinusitis develops first, and later, bacterial infection occurs. For these individuals, early treatment of allergic sinusitis may prevent development of secondary bacterial sinusitis.

If the condition dramatically improves after 1 - 2 months, antibiotics are stopped. The patient should continue with both the steroid and saline nasal solutions. If there is no improvement after this time, surgery may be considered. For some people with chronic sinusitis, however, the condition is not curable, and the goal of treatment is to improve the quality of life.

 Home remedies

.  Drinking plenty of fluids and getting lots of rest when needed is still the best bit of advice to ease the discomforts of the common cold. Water is the best fluid and helps lubricate the mucus membranes.

·  Chicken soup does, indeed, help congestion and ache.  The studies have reported that , the ingredients in the soup may have anti-inflammatory effects. In fact, any hot beverage may have similar soothing effects from steam.

·  Ginger tea, fruit juice, and hot tea with honey and lemon may all be helpful.

·  Spicy foods that contain hot peppers or horseradish may help clear sinuses.

·  Inhaling steam 2 - 4 times a day is extremely helpful. 

 The patient should sit comfortably and lean over a bowl of boiling hot water (no one should ever inhale steam from water as it boils) while covering the head and the bowl with a towel so the steam remains under the cloth. The steam should be inhaled continuously for 10 minutes. A mentholated or other aromatic preparation may be added to the water. Long, steamy showers, vaporizers, and facial saunas are alternatives.