Laboratory Tests and Ancillaries
Culture and Susceptibility Test
The culture and susceptibility test documents bacterial infection and resistance patterns. Cultures from direct aspiration of the sinus are recommended in patients who have failed empiric therapy. An alternative could be obtaining culture from the middle meatus via endoscopy. Nasopharyngeal swab culture is not recommended.
Imaging
Imaging studies are not usually indicated in uncomplicated rhinosinusitis because findings are often non-specific. These are indicated when there are signs and symptoms suggesting spread of infection beyond the paranasal sinuses and nasal cavity.
Nasal Endoscopy
Rhinosinusitis - Acute, Bacterial_DiagnosticsRigid endoscopy is preferred because it provides clear images and is more comfortable for patients. The procedure may reveal nasal polyps and/or mucopurulent discharge primarily from the middle meatus and/or edema or mucosal obstruction. The procedure facilitates culture and tissue sampling and enables endoscopists to perform nasal toileting.
Computed Tomography (CT) Scan
A computed tomography scan is used in the evaluation of the paranasal sinuses and bone erosion. The scan can be used in quantifying the extent of inflammatory disease based on the opacification of the paranasal sinuses. Indications for a CT scan include: The presence of alarm symptoms that suggest disease complications involving the orbit, intracranial structures, and adjacent bone; unilateral symptoms, blood-stained discharge, displacement of the eye, and eye pain; planning for surgery; and failure of medical therapy. Patients not responsive to empiric antimicrobial therapy should be referred to an otorhinolaryngologist for a decision to perform a CT scan.
Please see Otorhinolaryngologist Referral in the Evaluation section.
Magnetic Resonance Imaging (MRI)
An MRI with contrast to the paranasal sinuses may be considered for pediatric and adult patients suspected of orbital or central nervous system (CNS) involvement. This can better differentiate the presence of an abscess from inflamed tissue.
Radiography
Radiography is not required to diagnose acute rhinosinusitis unless complications or alternative diagnoses are suspected.
Other Procedures
Maxillary Sinus Taps (MST) for Sinus Puncture and Aspiration
Due to its invasive nature, maxillary sinus taps (MST) for sinus puncture and aspiration are performed by otorhinolaryngologists.
Please see Otorhinolaryngologist Referral in the Evaluation section.
Endoscopically Directed Middle Meatal Culture (EDMMC)
Endoscopically directed middle meatal culture (EDMMC) is a less invasive procedure than MST and performed by otorhinolaryngologists. This may also be used in collecting specimens for culture and susceptibility tests for unresolved cases of bacterial rhinosinusitis.
Please see Otorhinolaryngologist Referral in the Evaluation section.