Combined CT venography and pulmonary angiography: a comprehensive review

Area of Science:

• Radiology
• Vascular Imaging
• Diagnostic Medicine

Background:

• Computed tomographic venography and pulmonary angiography (CTVPA) was introduced in 1998.
• It serves as a single, noninvasive imaging examination for suspected thromboembolic disease.
• CTVPA identifies pulmonary embolism and deep venous thrombosis (DVT) in the abdomen, pelvis, thighs, and calves.

Purpose of the Study:

• To evaluate the efficacy of CTVPA in diagnosing deep venous thrombosis (DVT).
• To compare CTVPA with lower extremity sonography for venous imaging.
• To assess the diagnostic yield and optimal imaging parameters for CTVPA.

Main Methods:

• Retrospective review of 957 cases examined with CTVPA for suspected pulmonary embolism.
• Analysis of venographic data to identify DVT in various venous segments.
• Evaluation of imaging protocols, including contiguous helical acquisition and image thickness/interval.

Main Results:

• CTVPA venography demonstrated accuracy comparable to sonography for thigh veins.
• CTVPA allows rapid and comprehensive evaluation of the inferior vena cava, pelvic, calf, and superficial venous systems.
• A 10.5% frequency of DVT was observed in patients with suspected pulmonary embolism, with thrombosis distributed across common femoral, superficial femoral, popliteal, and deep calf veins.

Conclusions:

• CTVPA is an accurate and efficient imaging modality for diagnosing DVT and pulmonary embolism.
• It offers a comprehensive assessment of the venous system, reducing the need for additional sonographic studies.
• Optimized CTVPA protocols, such as 5- or 10-mm-thick images every 4 cm, ensure high accuracy while minimizing radiation dose.