Classification Illustration depicting<unk> <unk>  (or rhinosinusitis) is defined as an inflammation of the mucous membrane that lines the paranasal sinuses and is classified chronologically into several categories: * Acute<unk>  – A new infection that may last up to four weeks and can be subdivided symptomatically into severe and nonsevere. Some use definitions up to 12 weeks. * Recurrent acute<unk>  – Four or more full episodes of acute<unk>  that occur within one year * Subacute<unk>  – An infection that lasts between four and 12 weeks, and represents a transition between acute and chronic infection. * Chronic<unk>  – When the signs and symptoms last for more than 12 weeks. * Acute exacerbation of chronic<unk>  – When the signs and symptoms of chronic<unk>  exacerbate, but return to baseline after treatment. Roughly 90% of adults have had<unk>  at some point in their lives. Acute Health care providers distinguish bacterial and viral<unk>  by watchful waiting. If a person has had<unk>  for fewer than 10 days without the symptoms becoming worse, then the infection is presumed to be viral. When symptoms last more than 10 days or get worse in that time, then the infection is considered bacterial<unk> . Pain in the teeth and bad breath are also more indicative of bacterial disease. Imaging by either X-ray, CT or MRI is generally not recommended unless complications develop. Pain caused by<unk>  is sometimes confused for pain caused by pulpitis (toothache) of the maxillary teeth, and vice versa. Classically, the increased pain when tilting the head forwards separates<unk>  from pulpitis. For cases of maxillary<unk> , limited field CBCT imaging, as compared to periapical radiographs, improves the ability to detect the teeth as the sources for<unk> . A coronal CT picture may also be useful. Chronic For<unk>  lasting more than 12 weeks, a CT scan is recommended. On a CT scan, acute sinus secretions have a radiodensity of 10 to 25 Hounsfield units (HU), but in a more chronic state they become more viscous, with a radiodensity of 30 to 60 HU. Nasal endoscopy and clinical symptoms are also used to make a positive diagnosis. A tissue sample for histology and cultures can also be collected and tested. Nasal endoscopy involves inserting a flexible fiber-optic tube with a light and camera at its tip into the nose to examine the nasal passages and sinuses. Sinus infections, if they result in tooth pain, usually present with pain involving more than one of the upper teeth, whereas a toothache usually involves a single tooth. Dental examination and appropriate radiography aid in ruling out pain arises from a tooth. Image:Sinuses and<unk>  (5937085231).CT of chronic<unk>  File:CT of chronic<unk> .CT scan of chronic<unk> , showing a filled right maxillary sinus with sclerotic thickened bone. File:Brain MRI 112010 rgbca.MRI image showing<unk> . Edema and mucosal thickening appears in both maxillary sinuses. File:RtmaxobitinfectteethCT.Maxillary<unk>  caused by a dental infection associated with periorbital cellulitis File:FrontalSinusitisMark.Frontal<unk>  File:Maxilar<unk> .X-ray of left-sided maxillary<unk>  marked by an arrow. There is lack of the air transparency indicating fluid in contrast to the other side.
Sinusitis
Migraine
Rhinosinusitis
Common cold
Aerosinusitis
Laryngitis
Mastoiditis
Croup