Computed tomography in rheumatology - From DECT to high-resolution peripheral quantitative CT.

Area of Science:

• Radiology
• Rheumatology
• Medical Imaging

Background:

• Dual Energy Computed Tomography (DECT) and high-resolution peripheral quantitative CT (HR-pQCT) are advanced imaging modalities with emerging applications in rheumatology.
• DECT aids in the noninvasive diagnosis of crystal arthropathies, such as gout, and can differentiate them from calcium pyrophosphate deposition (CPPD).
• HR-pQCT provides detailed assessment of bone microarchitecture, crucial for evaluating erosions and osteophytes in inflammatory joint diseases.

Purpose of the Study:

• To review current updates and applications of DECT, iodine-DECT mapping, and HR-pQCT in rheumatology.
• To highlight the diagnostic capabilities of these techniques for conditions like gout and inflammatory arthritis.
• To discuss the potential of iodine quantification for monitoring therapeutic responses.

Main Methods:

• Discussion of current literature and clinical applications of DECT, iodine-DECT mapping, and HR-pQCT.
• Evaluation of DECT for diagnosing gout and differentiating from CPPD.
• Assessment of iodine mapping for delineating inflammatory lesions and quantifying iodine contrast.
• Utilization of HR-pQCT for sensitive measurement of bone damage in inflammatory joint diseases.

Main Results:

• DECT shows promise for noninvasive gout diagnosis, with accuracy varying by disease stage and limitations in deeper joints.
• Iodine-DECT mapping enhances visualization of inflammatory lesions (capsulitis, tenosynovitis) and offers objective monitoring of inflammatory arthritis treatment.
• HR-pQCT enables sensitive detection and tracking of bone erosions and osteophytes in inflammatory joint diseases, valuable for longitudinal studies.

Conclusions:

• DECT and HR-pQCT are valuable tools in rheumatology, offering noninvasive diagnostic and monitoring capabilities for various joint diseases.
• Iodine quantification via DECT presents a promising objective biomarker for assessing treatment efficacy in inflammatory arthritis.
• Further validation of automated image analysis for HR-pQCT is needed, alongside specialized training for image interpretation.