Characterizing Meniscal Calcifications with Photon Counting-Based Dual-Energy Computed Tomography.

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Orthopedics

Background:

• Meniscal calcifications are linked to meniscal degeneration and osteoarthritis (OA).
• Distinguishing between basic calcium phosphate (BCP) and calcium pyrophosphate (CPP) calcifications in vivo is challenging.
• New imaging techniques are needed to understand calcification pathologies and their OA relationship.

Purpose of the Study:

• To evaluate if photon counting detector dual-energy computed tomography (PCD-DECT) can differentiate BCP from CPP calcifications.
• To use Raman spectroscopy as a reference standard for calcification classification.
• To assess the potential of PCD-DECT for future in vivo applications.

Main Methods:

• 82 meniscus samples were analyzed using PCD-DECT at 120kVp.
• Raman spectroscopy classified calcifications as BCP or CPP.
• Regression models compared dual-energy index (DEI) and energy values between calcification types.

Main Results:

• Significant differences were observed in low-energy values and DEI between BCP and CPP calcifications.
• The highest difference in low-energy values was 166HU (95%CI: 73, 259) at 500HU.
• The difference in DEI values was 0.035 (95%CI: 0.011, 0.059).

Conclusions:

• PCD-DECT successfully measured BCP and CPP calcifications ex vivo.
• The findings suggest PCD-DECT's potential for in vivo diagnosis of meniscal calcifications.
• This technology could aid in understanding calcification processes and evaluating OA treatments.