A common theory surrounding the need and purpose of sinuses is that they help to lighten the entire weight of the skull. The ethmoid sinuses are located between the nose and eyes. The frontal sinuses are found in the forehead and eyebrow area. The maxillary sinuses are in the area of the cheekbones. The two major classifications of sinusitis are chronic and acute cases.
Acute sinusitis is the abnormal secretion and production of mucous.
This is similar to cystic fibrosis. On x-rays, acute sinusitis is suggested by air fluid levels in the sinuses. Chronic sinusitis is a disease usually diagnosed after a patient has had a sinus infection lasts longer than three weeks to three months. There are variable sources of chronic sinusitis that include allergies, asthma, nasal polyps, and damp weather. On x-rays, chronic sinusitis is seen as nasal sinus wall thickenings and bony sclerosis.