II. Epidemiology
- High False Positive Rate
- Upper Respiratory Infection: 85% with CT changes
- Asymptomatic adults: 40% with CT changes
- References
III. Advantages
- Much more sensitive than Sinus XRay
- Good Sinus Anatomy definition
- Views sphenoid and Ethmoid Sinuses well
- Defines osteomeatal complex well
IV. Indications
- Confusing presentation
- Evaluation before endoscopic surgery
-
Sinusitis refractory to maximal medical management
- Recurrent Acute Sinusitis
- Persistent Chronic Sinusitis Symptoms
- Suspected Osteomeatal complex Occlusion
- Suspected Allergic Fungal Sinusitis
- Suspected Fungal Sinusitis or other complicated Sinusitis (e.g. Immunocompromised patients)
- Sinusitis complications (e.g. Cavernous Sinus Thrombosis)
V. Technique
- Full Coronal non-contrast Sinus CT
- Standard view indicated in most cases
- Mucosal thickening >5mm is consistent with sinus infection
- Demonstrates fluid and mucosal edema, as well as bony destruction
- Fat stranding (increased density) may be present in para-sinus spaces
- Limited Sinus CT
- Consider as alternative to full Sinus CT
- Four non-contiguous 5 mm slices in coronal plane
- Frontal Sinus
- Anterior ethmoid and Maxillary Sinuses
- Posterior ethmoid and Maxillary Sinuses
- Sphenoid Sinus
- Advantages
- Less expensive
- Less radiation
- Disadvantage
- Unknown efficacy
- Contrast Sinus CT
- Indications
- Periorbital Cellulitis or abscess
- Vascular complications
- Cavernous Sinus Thrombosis
- Findings
- Necrotic tissue and fluid does not contrast enhance
- Inflamed, thickened mucosa contrast enhances
- Mucosa, fluid and soft tissue may be indistinguishable without contrast
- Consider IV contrast in complicated cases (e.g. vascular complications, Cavernous Sinus Thrombosis)
- Indications
VI. Timing
- Perform during maximal medical therapy
- Delay if URI present
VII. Contraindications: Relative
- Submaximal medical Management
- Upper Respiratory Infection
- Acute sinus infection
VIII. Interpretation
- Findings consistent with Rhinosinusitis
- Air-fluid levels
- Total opacification
- Mucosal thickening >5 mm
- Complications identified by Sinus CT
- Osteomeatal Complex Obstruction
- Allergic Fungal Sinusitis
IX. References
- Broder (2018) Crit Dec Emerg Med 32(10): 12-3
- Mukherji (1998) Radiology 207:417-22 [PubMed]
- Okuyemi (2002) Am Fam Physician 66:1882-6 [PubMed]
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Related Studies
| Concepts | Diagnostic Procedure (T060) |
| ICD10 | 56022-01 |
| SnomedCT | 241526005 |
| English | CT of paranasal sinuses (procedure), Computed tomography of paranasal sinuses (procedure), Computed tomography of paranasal sinuses, paranasal CT scan, computed tomography of paranasal sinuses, computed tomography of paranasal sinuses (procedure), CT scan of paranasal sinuses, Computerised tomography of paranasal sinus, Computerized tomography of paranasal sinus, CT of paranasal sinuses |
| Spanish | TC de senos paranasales, tomografía computarizada de senos paranasales (procedimiento), tomografía computarizada de senos paranasales |
Ontology: Computed tomography of sinuses (C1960838)
| Concepts | Diagnostic Procedure (T060) |
| SnomedCT | 425916005 |
| English | Computed tomography of sinuses (procedure), Computed tomography of sinuses |
| Spanish | TC sinusal, tomografía computarizada sinusal, tomografía computarizada sinusal (procedimiento) |
