Introduction
The standard approach to preparing for angiographic procedures has traditionally relied on conventional 2D imaging techniques, such as digital subtraction angiography (DSA), standard computed tomography (CT), or ultrasound and magnetic resonance imaging (MRI) These modalities provided essential diagnostic information but were limited in depicting the full complexity of vascular anatomy in three dimensions. Physicians often had to interpret multiple 2D images, mentally reconstructing the anatomy, which could lead to challenges in accurately identifying vascular pathologies or planning interventions. Additionally, this approach required a higher reliance on invasive diagnostic angiography to obtain detailed anatomical information, which increased the patient's exposure to radiation, contrast agents, and procedural risks. The limitations in visualizing tortuous or overlapping vessels made planning and executing complex procedures more difficult, potentially leading to suboptimal outcomes. Thus, while effective to a degree, the conventional methods had significant drawbacks compared to the capabilities offered by modern 3D visualization techniques.
CT 3D visualization before performing angiographic procedures offers the advantage of providing detailed and accurate anatomical representations. This technology allows clinicians to visualize the vascular structures in three dimensions, facilitating the identification of complex anatomical variations, stenoses, or aneurysms. CT 3D visualization offers a comprehensive view of the patient's vascular system, improving pre-procedural planning precision, reducing procedural risks, and enhancing outcomes by enabling the selection of the most appropriate interventional strategies.
Image Courtesy from Ng Teng Fong General Hospital
Case Study
A 50-year-old man with a long history of intravenous substance use and Hepatitis C, as well as liver cirrhosis complicated by coagulopathy, presented to the emergency department with bleeding in his right groin.
This is a compelling case involving a patient with a pseudoaneurysm and active bleeding. However, traditional 2D imaging has limitations. While the necessary information is present, it often lacks the clarity needed for effective diagnosis and treatment planning. In contrast, volumetric imaging provided a comprehensive, detailed, and versatile view.
The protocol consists of a contrast-enhanced CT scan performed on SOMATOM Force.
Image Courtesy from Ng Teng Fong General Hospital
50 year-old, Male
Presented to ED with massive bleeding from right groin
Pseudoaneurysm
Volumetric imaging, on the other hand, allowed precise identification of the pseudoaneurysm's size and neck and its relationship to surrounding structures such as vessels and bone. This multidimensional perspective enables clinicians to plan surgeries with greater accuracy.
Image Courtesy from Ng Teng Fong General Hospital
From another perspective, adjusting the imaging windows could reveal additional critical information, such as broken needles beneath the skin, which might not be too obvious in standard 2D images.
Volumetric imaging not only revealed the pseudoaneurysm but also showed that the patient's left thigh was smaller than the right. This was attributed to an occlusion in the left iliac artery, information that proved vital for the vascular surgeon or interventional radiologist (IR) in determining the safest and most effective approach for treatment. Treatment for this patient was then advised against puncturing the left groin to cross over to the right and instead recommended approaching from above to avoid complications.
The advanced imaging also allowed for a better-informed decision regarding treatment options. Given the detailed visualization of the aneurysm, the patient was suggested that a thrombin injection under ultrasound guidance could be a safer and less invasive alternative to traditional angiographic procedures. This approach underscores the importance of leveraging comprehensive CT volumetric data to plan procedures and achieve the best possible outcomes for patients.
3D image display using cinematic volume rendering technique on syngo.via with auto bone removal and vessel isolation.
Image Courtesy from Ng Teng Fong General Hospital
"By using the CT volumetric data, you get a lot of information; you can plan the procedure better and provide the best outcome for the patient.”
As radiology continues to evolve with the introduction of new imaging technologies, the importance of staying at the forefront of these advancements cannot be overstated. Embracing innovative tools like volumetric imaging can significantly enhance clinical practice. By improving diagnostic accuracy and treatment planning, such advancements are pushing the boundaries of what is possible in radiology and ensuring that patients receive the highest standard of care.
About the Author
Dr. Teh Hui Seong is a Senior Consultant in the Department of Radiology at Ng Teng Fong General Hospital and Jurong Community Hospital. His qualifications include MBBS (Singapore), FRCR (UK), and FAMS (Diagnostic Radiology). He has a special interest in interventional radiology. He is a strong advocate of User Experience (UX). He espouses integrating advanced imaging techniques into clinical practice to enhance patient care. He believes that patient engagement technology can offer a broader experience strategy that aligns quality, safety, and performance initiatives at all touchpoints across the care continuum.
