Can PET CT scans follow European Association of Nuclear Medicine (EANM) guidelines?

PET/CT Scans Should Follow EANM Guidelines for Optimal Clinical Results

PET/CT scans should follow the European Association of Nuclear Medicine (EANM) procedure guidelines for tumor imaging to ensure standardized, high-quality imaging with optimal diagnostic value. 1

EANM Guidelines for PET/CT Acquisition

Patient Preparation

• Patient preparation aims to reduce tracer uptake in normal tissues while optimizing uptake in target structures and keeping radiation exposure as low as reasonably achievable (ALARA) 1
• Complete medical history review should focus on tumor type, known tumor sites, oncological history, and relevant comorbidities (especially infection/inflammation and diabetes mellitus) 1
• Patient height and weight must be measured directly before each examination, particularly for standardized uptake value (SUV) measurements 1

CT Protocol Components

• PET/CT examinations typically include a topogram/scout scan followed by CT scan(s) 1
• CT acquisition parameters (tube current, voltage, slice thickness, rotation time, pitch) should be selected based on the examination objective 1
• Two main CT options are available within PET/CT studies:
  • Low-dose CT scan: Performed only for attenuation correction and anatomical correlation of PET findings, not intended for dedicated radiological interpretation 1
  • Diagnostic CT scan: With or without contrast agents, using higher X-ray doses according to local or national protocols 1

CT Acquisition Techniques

• The CT attenuation correction (CT-AC) scan should be performed during tidal or shallow breathing 1
• For CT systems with six or fewer rings, breath hold in normal expiration may be considered for thorax and upper abdomen scanning 1
• Ultra low-dose CT scans with iterative reconstruction methods can be used to further reduce radiation dose 1
• When using intravenous contrast, equilibrium or venous phase acquisition is preferred; arterial phase CT acquisitions should be avoided 1

Special Protocols

• For dedicated brain imaging:
  • Patient preparation should follow brain scan protocols 1
  • Arms down position with head fixed in a holder 1
  • CT topogram of head, followed by low-dose CT scan 1
  • 5-minute PET acquisition 45-50 minutes after injection (300-400 MBq) 1
  • Brain image reconstruction performed independently from body scan 1

Important Considerations

Contrast Agent Use

• High intravenous or intestinal concentrations of contrast agent may cause artifacts in reconstructed PET images following CT attenuation correction 1
• When CT data are collected in the equilibrium or venous phase, the impact of intravenous contrast agents on attenuation correction accuracy is generally acceptable 1
• For FDG PET/CT studies without need for advanced quantification, intravenous contrast agents can be used directly for attenuation correction 1, 2

Quality Control

• Images should be reviewed before the patient leaves the department to ensure technical adequacy and to assess any need for additional imaging 1
• Decay correction must be turned on for accurate quantification 1
• All patient information, including height, weight, radiopharmaceutical details, and net activity administered should be carefully entered into the PET/CT system 1

Clinical Applications

• EANM guidelines cover various clinical applications including:
  • Detecting and localizing abnormal glucose metabolism in patients with suspected or known malignancies 1
  • Staging patients with known malignancies 1
  • Monitoring therapy effects on known malignancies 1
  • Determining whether residual abnormalities represent tumor or post-treatment changes 1
  • Detecting tumor recurrence, especially with elevated tumor markers 1
  • Selecting optimal biopsy sites 1
  • Guiding radiation therapy planning 1
  • Specific guidelines for plasma cell disorders 1

Pitfalls and Caveats

• Deep inspiration chest CT scans should not be used for attenuation correction when PET quantification is required 1
• Side-by-side viewing of PET and CT scans is essential in approximately 42.4% of cases for correct diagnosis 3
• Integrated PET/CT may provide additional information in approximately 6.7% of patients 3
• Radiation safety considerations are important for both patients and staff due to the combination of two radiation-based procedures 4

Following EANM guidelines ensures standardized acquisition protocols, proper patient preparation, and appropriate technical parameters, leading to high-quality PET/CT images with optimal diagnostic value.