Where Does It Lead? Imaging Features of Cardiovascular Implantable Electronic Devices on Chest Radiograph and CT

Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein.     

CT protocols in interstitial lung diseases—A survey among members of the European Society of Thoracic Imaging and a review of the literature

Purpose

The aim of this study was to survey the current CT protocols used by members of the European Society of Thoracic Imaging (ESTI) to evaluate patients with interstitial lung diseases (ILD).

Methods

A questionnaire was e-mailed to 173 ESTI members. The survey focussed on CT acquisition and reconstruction techniques. In particular, questions referred to the use of discontinuous HRCT or volume CT protocols, the acquisition of additional acquisitions in expiration or in the prone position, and methods of radiation dose reduction and on reconstruction algorithms.

Results

The overall response rate was 37 %. Eighty-five percent of the respondents used either volume CT alone or in combination with discontinuous HRCT. Forty-five percent of the respondents adapt their CT protocols to the patient’s weight and/or age. Expiratory CT or CT in the prone position was performed by 58 % and 59 % of the respondents, respectively. The number of reconstructed series ranged from two to eight.

Conclusion

Our survey showed that radiologists with a special interest and experience in chest radiology use a variety of CT protocols for the evaluation of ILD. There is a clear preference for volumetric scans and a strong tendency to use the 3D information.

Key Points

? Experienced thoracic radiologists use various CT protocols for evaluating interstitial lung diseases. ? Most workers prefer volumetric CT acquisitions, making use of the 3D information ? More attention to reducing the radiation dose appears to be needed     

Coronary CT angiography after stress testing: An efficient use of resources? Implications of the Advanced Cardiovascular Imaging Consortium (ACIC) results

Coronary CT angiography (CCTA) has matured to be a fast noninvasive imaging test in the evaluation of coronary artery disease (CAD). It has demonstrated excellent accuracy for defining the presence and the severity of luminal coronary artery stenoses and is probably the best noninvasive test to reliably exclude atherosclerotic coronary disease. Furthermore, accumulating CCTA data indicate that it can identify individuals at risk for all-cause mortality. It is also well known that despite the wealth of data regarding diagnostic and prognostic values of stress testing in CAD, up to 10% of stress imaging studies are considered inconclusive, leading to subsequent invasive coronary angiography for definitive diagnosis often with negative results. Moreover, recent data indicate that up to 30 % of patients undergoing angiography have no significant CAD despite a majority of them having had a prior stress test. Whether CCTA can serve as a cost-effective methodology to invasive angiography has been a source of active research. In this context, we will discuss the implications of the recently published data from the Advanced Cardiovascular Imaging Consortium registry looking at the use of CCTA after stress testing in Michigan.     

Magnetic Resonance Imaging–guided Volumetric Ablation of Symptomatic Leiomyomata: Correlation of Imaging with Histology

PurposeTo describe the preliminary safety and accuracy of a magnetic resonance (MR) imaging–guided high-intensity–focused ultrasound (HIFU) system employing new technical developments, including ablation control via volumetric thermal feedback, for the treatment of uterine leiomyomata with histopathologic correlation.Materials and MethodsIn this phase I clinical trial, 11 women underwent MR-guided HIFU ablation (Sonalleve 1.5T; Philips Medical Systems, Vantaa, Finland), followed by hysterectomy within 30 days. Adverse events, imaging findings, and pathologic confirmation of ablation were assessed. The relationship between MR imaging findings, thermal dose estimates, and pathology and HIFU spatial accuracy were assessed using Bland-Altman analyses and intraclass correlations.ResultsThere were 12 leiomyomata treated. No serious adverse events were observed. Two subjects decided against having hysterectomy and withdrew from the study before surgery. Of 11 women, 9 underwent hysterectomy; all leiomyomata demonstrated treatment in the expected location. A mean ablation volume of 6.92 cm³ ± 10.7 was observed at histopathologic examination. No significant differences between MR imaging nonperfused volumes, thermal dose estimates, and histopathology ablation volumes were observed (P > .05). Mean misregistration values perpendicular to the ultrasound beam axis were 0.8 mm ± 1.2 in feet-head direction and 0.1 mm ± 1.0 in and left-right direction and ?0.7 mm ± 3.1 along the axis.ConclusionsSafe, accurate ablation of uterine leiomyomata was achieved with an MR-guided HIFU system with novel treatment monitoring capabilities, including ablation control via volumetric thermal feedback.     

Imaging of penile traumas—therapeutic implications

Injury to the penis may result from penetrating or nonpenetrating trauma. Nonpenetrating injury to the erect penis can produce albugineal tear, intracavernous hematoma or extraalbugineal hematoma from rupture of the dorsal vessels. Nonpenetrating injury to the flaccid penis usually follows blunt perineal traumas producing extratunical or cavernosal haematomas, or cavernosal artery tear followed by high flow priapism. Differential diagnosis between albugineal tear and other penile injuries must be obtained as soon as possible, since early surgical repair of albugineal tear reduces significantly the rate of postraumatic curvature and fibrosis. Ultrasonography (US) is able to detect the exact site of the tear in most patients as an interruption of the thin echogenic line of the tunica albuginea. Other imaging techniques are rarely required in the clinical practice. Color Doppler US is the imaging modality of choice to evaluate patients with high flow priapism. Focal or diffuse cavernosal fibrosis can be identified with US as echogenic areas in the cavernosal bodies. Postraumatic erectile dysfunction can result from fibrotic changes, nerve and vascular impairment or both. Doppler evaluation of penile vasculature is required in young patients with postraumatic impotence before surgical revascularization procedures.     

Imaging of tendons—adaptation,degeneration, rupture

Tendon imaging is mainly performed with ultrasonography (US) and magnetic resonance imaging (MRI) and has been improved within the last years because of technical advancements and a better understanding of tendon pathology. Several concepts concerning the etiology and the course of tendon diseases have influenced image interpretation and vice versa. Adaptive mechanisms within the tendon tissue against stress can be observed mainly on histologic specimens and not macroscopically or with in-vivo imaging. Degeneration may occur in the form of tendinitis, peritendinitis, enthesitis, or myotendinal junction abnormality. Distinct imaging findings exist for most of these forms. Many concepts that have been developed to explain tendon degeneration have been applied on virtually all tendons in the human body. They can be grouped into those which focus on hypovascularization, on biomechanical overload, and on degeneration secondary to other underlying disease. Tendon rupture seems, in many cases, to be the final stage of tendinitis. From this point of view, imaging may be used to predict the risk of tendon rupture together with other intrinsic and with extrinsic parameters. These considerations result in the concept of the ‘vulnerable zone’ and of the ‘critical phase’ in which tendon ruptures may predominantly occur.     

Lack of Timely Follow-Up of Abnormal Imaging Results and Radiologists’ Recommendations

PurposeAbnormal imaging results may not always lead to timely follow-up. We tested whether certain aspects of communication in radiology reports influence the response of the referring providers, and hence follow-up on abnormal findings.MethodsWe focused on 2 communication-related items that we hypothesized could affect follow-up: expressions of doubt in the radiology report, and recommendations for further imaging. After institutional review board approval, we conducted a retrospective review of 250 outpatient radiology reports from a multispecialty ambulatory clinic of a tertiary-care Veterans Affairs facility. The selected studies included 92 cases confirmed to lack timely follow-up (ie, further tests or consultations, treatment, and/or communication to the patient within 4 weeks), as determined in a previous study. An additional 158 cases with documented timely follow-up served as controls. Doubt in the narrative was measured by the presence of key phrases (eg, “unable to exclude,” “cannot exclude,” “cannot rule out,” “possibly,” and “unlikely”), in the absence of which we used reviewer interpretation. A physician blinded to follow-up outcomes collected the data.ResultsPatients whose reports contained recommendations for further imaging were more likely to have been lost to follow-up at 4 weeks compared with patients without such recommendations (P = .01). Language in the report suggestive of doubt did not affect the timeliness of follow-up (P = .59).ConclusionsAbnormal imaging results with recommendations for additional imaging may be more vulnerable to lack of timely follow-up. Additional safeguards, such as tracking systems, should be developed to prevent failure to follow up on such results.     

Imaging of the spine: Where do we stand?

The number of patients presenting with spine-related problems has globally increased, with an enormous growing demand for the use of medical imaging to address this problem. The last three decades witnessed great leaps for diagnostic imaging modalities, including those exploited for imaging the spine. These developments improved our diagnostic capabilities in different spinal pathologies, especially with multi-detector computed tomography and magnetic resonance imaging, via both hardware and software improvisations. Nowadays, imaging may depict subtle spinal instability caused by various osseous and ligamentous failures, and could elucidate dynamic instabilities. Consequently, recent diagnostic modalities can discern clinically relevant spinal canal stenosis. Likewise, improvement in diagnostic imaging capabilities revolutionized our understanding of spinal degenerative diseases via quantitative biomarkers rather than mere subjective perspectives. Furthermore, prognostication of spinal cord injury has become feasible, and this is expected to be translated into better effective patient tailoring to management plans with better clinical outcomes. Meanwhile, our confidence in diagnosing spinal infections and assessing the different spinal instrumentation has greatly improved over the past few last decades. Overall, revolutions in diagnostic imaging over the past few decades have upgraded spinal imaging from simple subjective and qualitative indices into a more sophisticated yet precise era of objective metrics via deploying quantitative imaging biomarkers.     

The Journal of Cardiovascular Computed Tomography year in review – 2019

The purpose of this review is to summarize the work published by the Journal of Cardiovascular Computed Tomography (JCCT) for the year 2019, highlighting original research and new guidelines.     

Musculoskeletal Imaging with Computed Tomography and Magnetic Resonance Imaging: When is Computed Tomography the Study of Choice?

Indications for computed tomography (CT) of the musculoskeletal system, especially with the advent of 16-slice multidetector CT (MDCT), are numerous. In addition to the evaluation of the trauma patient where CT is essential when imaging complex skeletal injuries, MDCT is particularly useful in patients who have had prior surgery. In postoperative cases, metal artifact typically prohibits magnetic resonance imaging evaluation, but volume-rendering of a MDCT axial database virtually eliminates streak artifact associated with hardware. For the evaluation of masses, CT provides the ability to detect and characterize calcification, cortical disruption, and periosteal reaction. In this article, these and other indications for performance of CT of the musculoskeletal system will be discussed.