Rajiah, Prabhakar

Chest CTs done for unrelated reasons have the potential to reveal unsuspected abnormalities and provide complementary information to help direct appropriate management. By thoroughly understanding the diagnostic role and limitations of CT in assessing ventricular size and morphology as well as myocardial attenuation, enhancement, and thickness, radiologists will be better equipped to differentiate between normal and abnormal findings and provide precise, clinically appropriate recommendations.

The cardiac imager should be familiar with the types of motion artifacts commonly encountered in cardiac CT, some of which can be corrected or at least minimized without having to rescan the patient.

Renovascular hypertension is the most common cause of secondary hypertension, and radiologist awareness of the various imaging appearances and various causes is crucial for accurate diagnosis and guiding treatment.

Alcohol use disorder is linked to a multitude of diseases and disorders, many of which can be diagnosed with imaging techniques such as US, CT, and MRI, enabling early detection and potentially preventing further damage and improving outcomes.

Photon-counting detector CT offers improved assessment of small stents and higher diagnostic accuracy than conventional CT through enhanced spatial resolution and spectral reconstructions.

Abstract Background Coronary computed tomography angiography (cCTA) is a widely used noninvasive diagnostic exam to assess patients for coronary artery disease (CAD). However, the spatial resolution of most CT scanners is limited due to the use of energy‐integrating detectors (EIDs). Purpose To develop a convolutional neural network ( I mproved LUMEN visualization through A rtificial super‐resolu T ion imag E s (ILUMENATE)) informed by photon‐counting‐detector (PCD)‐CT to improve EID‐CT image resolution and determine its impact on cCTA. Materials and methods With IRB approval, 30 patients undergoing clinically indicated cCTA were scanned with EID‐CT (SOMATOM Force, Siemens Healthineers, Forchheim, Germany) and subsequently with ultra‐high‐resolution (UHR) PCD‐CT (NAEOTOM Alpha, Siemens Healthineers) on the same day. ILUMENATE was trained on eight patient PCD‐CT datasets (67,890 patch pairs with 90% for training (61,101), 10% reserved for validation (6,789)) and applied to 22 unseen EID‐CT cases. Spatial resolution was evaluated using line profiles and percent diameter stenosis quantified with a severity score assigned. Two experienced radiologists, blinded to image type, selected preferred series and scored images for overall quality, sharpness, and noise comparing original EID‐CT and ILUMENATE output. Results Visual assessment and line profiles showed substantial resolution improvement with ILUMENATE. Percent diameter stenosis was significantly reduced (mean ± standard deviation: 4.42% ± 4.82%) using ILUMENATE ( p < 0.001) with nine lesions shifting down in severity score. Readers preferred ILUMENATE images in 22/22 cases and scored ILUMENATE superiorly for overall quality, sharpness, and noise ( p < 0.05). Conclusions ILUMENATE enhanced image resolution, resulting in improved overall image quality, reduced calcium blooming artifacts, and improved lumen visibility in cCTA exams performed using EID‐CT. This could potentially allow for improved accessibility to UHR image quality, allowing for more accurate assessment of CAD.

Abstract Quantitative computed tomography (CT) enables the measurement of biophysical processes characterized by morphology, composition, flow, and/or motion to aid in clinical diagnosis and intervention. Since its initial application for determining bone mineral density for skeletal fragility assessment, quantitative CT has continued to evolve alongside CT’s technological advancements. A key challenge facing quantitative CT is the lack of standardization pertinent to image acquisition, reconstruction, and image analysis. With the introduction of spectral CT involving dual-energy approaches and photon-counting detectors (PCD), we are now able to obtain detailed information regarding mass densities of endogenous and exogeneous materials. Furthermore, energy-resolved CT yields spectral image types (eg, virtual monoenergetic image) that are, in principle, independent of tube potential and patient size. This paves the way for workflow standardization and helps improve the consistency and reproducibility of CT-derived measurements. In this article, we review clinical applications of quantitative CT, discuss key challenges associated with quantitative CT and its adoption into routine practice, and outline the unique benefits ushered by new CT technologies such as PCD-CT towards improving quantitative imaging.

MRI and CT play an important role in sports cardiology, including preparticipation evaluation, distinguishing adaptive changes of athlete’s heart from pathologic entities, and evaluation following cardiovascular symptoms or adverse events.

Abstract Background: Prostate artery embolization (PAE) requires a careful understanding of pelvic arterial anatomy and identifying prostatic artery variants. Pre-procedure CTA and intra-procedural cone beam CT are traditional means of planning and performing PAE, with the latter providing guidance for embolization. Photon counting detector (PCD) CT is a novel technology enabling ultra-high spatial resolution (UHR) whole-body imaging, with reconstructed slices as thin as 200 um. For PAE, we obtain a single UHR PCD CT acquisition, which provides both detailed pre-procedure pelvic arterial anatomy information and a registration reference for intra-procedural embolization guidance. Case Presentation: In five patients who underwent technically successful PAE via a left transradial approach, the pre-procedure diagnostic UHR PCD prostate CTA delineated bilateral prostatic artery origins and course in all cases, as confirmed with conventional angiograms. Further, registration of the UHR PCD CT for embolization guidance was successful in all cases, augmenting vessel selection. No complication occurred. Conclusion: UHR PCD CT is a novel acquisition option that is well suited to PAE due to its ability to delineate small vessels. Further, our experience has shown that a single pre-procedure scan can also be utilized for intra-procedural embolization guidance, obviating the need for a traditional cone beam CT angiogram. Further research is needed to assess reductions in radiation dose, contrast use, and intra-procedural time with these techniques.