What type of scan is recommended to determine if there are polyps in a patient with chronic sinusitis?

CT Scan is the Gold Standard for Detecting Nasal Polyps in Chronic Sinusitis

CT scan is the gold standard imaging modality for evaluating chronic sinusitis and detecting nasal polyps, offering superior visualization of both bony anatomy and soft tissue abnormalities. 1

Diagnostic Options for Detecting Nasal Polyps

Clinical Examination

• Initial assessment should include careful examination of the nasal airway, but this has limitations for detecting smaller polyps 1
• Large polyps obstructing the nasal cavity can be visualized with a nasal speculum or handheld otoscope 1
• Small nasal polyps in the middle meatus or posterior nasal cavity may only be detected by nasal endoscopy 1
• If nasal endoscopy cannot be performed, referral to a specialist who can thoroughly examine the nasal cavity is recommended 1

CT Scanning

• CT scan remains the gold standard in radiologic evaluation of chronic rhinosinusitis and nasal polyps 1
• Provides detailed information on:
  • Extent of polyp involvement throughout the nasal cavity 1
  • Status of bony landmarks (e.g., lamina papyracea) 1
  • Integrity of the orbit and cranial vault 1
  • Anatomical variants that may contribute to sinus disease 1
• Particularly useful for:
  • Unilateral polyps 1
  • Polyps extending outside the nasal cavity 1
  • Atypical presentations 1
  • Preoperative evaluation 1, 2
• Multiplanar CT imaging offers both bone detail and soft-tissue imaging 1
• Coronal CT provides excellent anatomic bony detail, either with thin-slice axial images with reformations or direct coronal images 1
• Intravenous contrast is generally not needed for routine evaluation 1

MRI

• Limited role in routine evaluation of chronic sinusitis and nasal polyps 1
• Reserved for specific situations:
  • Differentiating soft-tissue structures 3
  • Suspected fungal infection 4
  • Suspected neoplasm 2, 4
  • Evaluating potential complications (orbital or intracranial) 2

Plain Radiography

• Limited role in the management of sinusitis and detection of polyps 3
• Less accurate than CT with significant false-positive and false-negative results 1
• Has been largely supplanted by CT when imaging is necessary 1

CT Scan Interpretation and Scoring

• The Lund-Mackay scoring system is commonly used to quantify sinus disease on CT 1, 5
• Based on degree of opacification for each sinus (0-none; 1-partial; 2-complete) and OMC (0 or 2) 1
• Maximum score of 24 (12 per side) 1
• CT findings in chronic rhinosinusitis remain relatively consistent over time, making it a reliable diagnostic tool 6

Clinical Considerations

• CT findings should always be correlated with clinical symptoms and endoscopic findings 5
• CT scan alone may show abnormalities in asymptomatic individuals, so clinical correlation is essential 3
• The presence of nasal polyps affects treatment management, particularly regarding the use of topical or systemic corticosteroid therapy 1
• Approximately 4% of patients with chronic rhinosinusitis have concurrent polyps 1
• There is an association between asthma, nasal polyps, and aspirin sensitivity 1

When to Order Imaging

• CT is recommended after failure of appropriate medical or surgical treatment in secondary care with continued symptoms and abnormal endoscopy 1
• CT should be obtained in diagnosing or evaluating patients with chronic rhinosinusitis or recurrent acute rhinosinusitis 1
• CT is typically reserved for difficult cases or to define anatomy prior to sinus surgery 3

In conclusion, while nasal endoscopy can detect many polyps, CT scanning is the most comprehensive and reliable imaging method for detecting nasal polyps in chronic sinusitis, especially when evaluating the full extent of disease or planning surgical intervention.