Prevalence and Natural History of Coronary Ostial Aneurysms in Marfan Patients.

OBJECTIVE: The aim of this study was to determine the prevalence and natural history of coronary ostial aneurysms in Marfan patients with aortic root replacement. METHODS: Thirty-one Marfan patients (mean age, 33.7 ± 11.8 years) who underwent aortic root replacement and postoperative electrocardiogram-gated computed tomographic (CT) angiograms between January 2007 and December 2015 were retrospectively identified. A subset of 15 patients underwent follow-up CT angiograms. Computed tomographic angiograms were postprocessed on 3-dimensional software to measure maximal coronary ostial diameter. Coronary ostial aneurysm was defined as diameter of greater than 10 mm. RESULTS: Right coronary ostial aneurysms were present in 45.2% (14/31) of patients, and left main coronary ostial aneurysms were present in 51.6% (16/31) of patients. Mean ostial diameter was 10.1 ± 1.9 mm for the right coronary artery and 10.0 ± 1.8 mm for the left coronary artery. In a subset of patients with follow-up CT angiograms, there was no significant change in coronary ostial diameter on follow-up examinations (P > 0.05). CONCLUSIONS: Coronary ostial aneurysms were common in Marfan patients after aortic root replacement. These findings remain stable over time and may have little clinical consequence.

Carotid Artery Tortuosity Index Is Associated With the Need for Early Aortic Root Replacement in Patients With Loeys-Dietz Syndrome.

OBJECTIVE: This study aimed to determine if carotid arterial tortuosity represents a marker of disease severity in Loeys-Dietz syndrome (LDS). METHODS: Fifty-four 54 LDS patients (mean age, 17.0 years) who underwent computed tomogram angiography from January 2004 to December 2013 were retrospectively identified. Carotid artery tortuosity index (CATI) was calculated from computed tomogram angiography. Clinical variables were obtained from the medical records. Relationship between CATI and need for aortic root replacement was evaluated with Cox proportional hazard model and Kaplan-Meier analysis. RESULTS: Higher CATI was associated with the need for aortic root replacement (P < 0.001) in the univariate Cox proportional hazard model. Patients were stratified based on both CATI and aortic root size in Kaplan-Meier analysis, and patients with higher CATI were more likely to require aortic root replacement (P < 0.001) in both aortic root size strata. CONCLUSION: Increased carotid artery tortuosity is associated with the need for early aortic root replacement in patients with LDS.

Gestational Trophoblastic Disease: Clinical and Imaging Features.

Gestational trophoblastic disease (GTD) is a spectrum of both benign and malignant gestational tumors, including hydatidiform mole (complete and partial), invasive mole, choriocarcinoma, placental site trophoblastic tumor, and epithelioid trophoblastic tumor. The latter four entities are referred to as gestational trophoblastic neoplasia (GTN). These conditions are aggressive with a propensity to widely metastasize. GTN can result in significant morbidity and mortality if left untreated. Early diagnosis of GTD is essential for prompt and successful management while preserving fertility. Initial diagnosis of GTD is based on a multifactorial approach consisting of clinical features, serial quantitative human chorionic gonadotropin (ß-hCG) titers, and imaging findings. Ultrasonography (US) is the modality of choice for initial diagnosis of complete hydatidiform mole and can provide an invaluable means of local surveillance after treatment. The performance of US in diagnosing all molar pregnancies is surprisingly poor, predominantly due to the difficulty in differentiating partial hydatidiform mole from nonmolar abortion and retained products of conception. While GTN after a molar pregnancy is usually diagnosed with serial ß-hCG titers, imaging plays an important role in evaluation of local extent of disease and systemic surveillance. Imaging also plays a crucial role in detection and management of complications, such as uterine and pulmonary arteriovenous fistulas. Familiarity with the pathogenesis, classification, imaging features, and treatment of these tumors can aid in radiologic diagnosis and guide appropriate management. ©RSNA, 2017.

Endovascular management of fusiform aneurysms in the posterior circulation: the era of flow diversion.

Fusiform aneurysms are uncommon compared with their saccular counterparts, yet they remain very challenging to treat and are associated with high rates of rebleeding and morbidity. Lack of a true aneurysm neck renders simple clip reconstruction or coil embolization usually impossible, and more advanced techniques are required, including bypass, stent-assisted coiling, and, more recently, flow diversion. In this article, the authors review posterior circulation fusiform aneurysms, including pathogenesis, natural history, and endovascular treatment, including the role of flow diversion. In addition, the authors propose an algorithm for treatment based on their practice.

Three-Dimensional Quantitative Tumor Response and Survival Analysis of Hepatocellular Carcinoma Patients Who Failed Initial Transarterial Chemoembolization: Repeat or Switch Treatment?

OBJECTIVES: The purpose of this study was to assess treatment responses and evaluate survival outcomes between responders and non-responders after each transarterial chemoembolization (TACE) session using the 3D quantitative criteria of the European Association for the Study of the Liver (qEASL) in hepatocellular carcinoma (HCC) patients. METHODS: A total of 94 consecutive patients who underwent MR imaging before and after TACE were retrospectively included. Volumetric tumor enhancement (qEASL) was expressed in cubic centimeters (cm3). The Kaplan-Meier method with the log-rank test was used to calculate the overall survival (OS) for the non-/responders. RESULTS: In total, 28 (29.8%) patients showed a response after the first TACE. These responders demonstrated a clear trend toward longer OS compared with the non-responders (36.7 vs. 21.5 months, p = 0.071). Of the 43 initial non-responders who underwent a second TACE within 3 months and had complete follow-up imaging, 15/43 (34.9%) achieved a response, and their median OS was significantly longer than that of the 28 non-responders to the second TACE (47.8 vs. 13.6 months, p = 0.01). Furthermore, there was no significant difference in OS between the 28 patients who achieved a response after the first TACE and the 15 initial non-responders who achieved a response after the second TACE (36.7 vs. 47.8 months, p = 0.701). The difference in OS between the responders and non-responders after the third TACE was not significant (11.4 months vs. 13.5 months, p = 0.986). CONCLUSION: Our study quantitatively demonstrated that a second TACE can be beneficial in terms of tumor response and survival for HCC patients who do not initially respond to TACE.

Metal Artifact Reduction Computed Tomography of Arthroplasty Implants: Effects of Combined Modeled Iterative Reconstruction and Dual-Energy Virtual Monoenergetic Extrapolation at Higher Photon Energies.

OBJECTIVE: The aim of this study was to compare the effects of combined virtual monoenergetic extrapolation (VME) of dual-energy computed tomography data and iterative metal artifact reduction (iMAR) at higher photon energies on low- and high-density metal artifacts and overall image quality of the ankle arthroplasty implants with iMAR, weighted filtered back projection (WFBP), and WFBP-based VME. MATERIALS AND METHODS: Total ankle arthroplasty implants in 6 human cadaver ankles served as surrogates for arthroplasty implants. All specimens underwent computed tomography with a 2 × 192-slice dual-source computed tomography scanner at tube voltages of 80 and tin-filtered 150 kVp to produce mixed 120 kVp equivalent polychromatic and virtual monoenergetic extrapolated images at 150 and 190 keV (VME 150 and VME 190, respectively). By implementing the WFBP and iMAR reconstruction algorithms on polychromatic, VME 150 and VME 190 data, 6 image datasets were created: WFBP-Polychromatic, iMAR-Polychromatic, WFBP-VME 150, WFBP-VME 190, iMAR-VME 150, and iMAR-VME 190. High-density and low-density artifacts were separately quantified with a threshold-based computer algorithm. After anonymization and randomization, 2 observers independently ranked the datasets for overall image quality. Repeated measures analysis of variance, Friedman, and Cohen weighted κ tests were applied for statistical analysis. A conservative P value of less than 0.001 was considered statistically significant. RESULTS: iMAR-VME 190 keV and iMAR-VME 150 keV created the least amount of high-density artifacts (all P < 0.001), whereas iMAR-Polychromatic was the most effective method to mitigate low-density streaks (P < 0.001). For low- and high-density artifacts, polychromatic iMAR acquisition was superior to WFBP-VME 150 keV and WFBP-VME 190 keV (all P < 0.001). On sharp kernel reconstructions, readers ranked the overall image quality of iMAR-Polychromatic images highest (all P < 0.001). Similarly, on soft tissue kernel reconstructions, readers ranked iMAR-Polychromatic images highest with a statistically significant difference over other techniques (all P < 0.001), except for iMAR-VME 150 keV (P = 0.356). CONCLUSIONS: In computed tomography imaging of ankle arthroplasty implants, iMAR reconstruction results in fewer metal artifacts and better image quality than WFBP reconstruction for both polychromatic and virtual monoenergetic data. The combination of iMAR and VME at higher photon energies results in mixed effects on implant-induced metal artifacts, including decreased high-density and increased low-density artifacts, which in combination does not improve image quality over iMAR reconstruction of the polychromatic data. Our results suggest that, for ankle arthroplasty implants, the highest image quality is obtained by iMAR reconstruction of the polychromatic data without the need to implement VME at high-energy levels.

Characteristics of a New X-Ray Imaging System for Interventional Procedures: Improved Image Quality and Reduced Radiation Dose.

PURPOSE: To compare image quality and radiation exposure between a new angiographic imaging system and the preceding generation system during uterine artery embolization (UAE). MATERIALS AND METHODS: In this retrospective, IRB-approved two-arm study, 54 patients with symptomatic uterine fibroids were treated with UAE on two different angiographic imaging systems. The new system includes optimized acquisition parameters and real-time image processing algorithms. Air kerma (AK), dose area product (DAP) and acquisition time for digital fluoroscopy (DF) and digital subtraction angiography (DSA) were recorded. Body mass index was noted as well. DF image quality was assessed objectively by image noise measurements. DSA image quality was rated by two blinded, independent readers on a four-rank scale. Statistical differences were assessed with unpaired t tests and Wilcoxon rank-sum tests. RESULTS: There was no significant difference between the patients treated on the new (n = 36) and the old system (n = 18) regarding age (p = 0.10), BMI (p = 0.18), DF time (p = 0.35) and DSA time (p = 0.17). The new system significantly reduced the cumulative AK and DAP by 64 and 72%, respectively (median 0.58 Gy and 145.9 Gy*cm2 vs. 1.62 Gy and 526.8 Gy*cm2, p < 0.01 for both). Specifically, DAP for DF and DSA decreased by 59% (75.3 vs. 181.9 Gy*cm2, p < 0.01) and 78% (67.6 vs. 312.2 Gy*cm2, p < 0.01), respectively. The new system achieved a significant decrease in DF image noise (p < 0.01) and a significantly better DSA image quality (p < 0.01). CONCLUSIONS: The new angiographic imaging system significantly improved image quality and reduced radiation exposure during UAE procedures.

Prostate Brachytherapy seed migration to the Bladder presenting with Gross Hematuria.

We present the radiologic findings in a case of prostate brachytherapy seed migration to the bladder presenting as gross hematuria. While prostate brachytherapy seed implantation is considered a relatively safe procedure, migration is not uncommon; however, it is usually clinically silent and the seeds most commonly migrate to the lungs through the venous circulation via the periprostatic venous plexus. Our case illustrates that local erosion is possible, can be symptomatic, and therefore must be considered when evaluating select patients.

Improved Visibility of Metastatic Disease in the Liver During Intra-Arterial Therapy Using Delayed Arterial Phase Cone-Beam CT.

PURPOSE: To compare the visibility of liver metastases on dual-phase cone-beam CT (DP-CBCT) and digital subtraction angiography (DSA), with reference to preinterventional contrast-enhanced magnetic resonance imaging (CE-MRI) of the liver. METHODS: This IRB-approved, retrospective study included 28 patients with neuroendocrine (NELM), colorectal (CRCLM), or sarcoma (SLM) liver metastases who underwent DP-CBCT during intra-arterial therapy (IAT) between 01/2010 and 10/2014. DP-CBCT was acquired after a single contrast agent injection in the tumor-feeding arteries at early and delayed arterial phases (EAP and DAP). The visibility of each lesion was graded by two radiologists in consensus on a three-rank scale (complete, partial, none) on DP-CBCT and DSA images using CE-MRI as reference. RESULTS: 47 NELM, 43 CRCLM, and 16 SLM were included. On DSA 85.1, 44.1, and 37.5 % of NELM, CRCLM, and SLM, were at least partially depicted, respectively. EAP-CBCT yielded significantly higher sensitivities of 88.3 and 87.5 % for CRCLM and SLM, respectively (p < 0.01), but not for NELM (89.4 %; p = 1.0). On DAP-CBCT all NELM, CRCLM, and SLM were visible (p < 0.001). Complete depiction was achieved on DSA for 59.6, 16.3, and 18.8 % of NELM, CRCLM, and SLM, respectively. The complete depiction rate on EAP-CBCT was significantly higher for CRCLM (46.5 %; p < 0.001), lower for NELM (40.4 %; p = 0.592), and similar for SLM (25 %, p = 0.399). On DAP-CBCT however, the highest rates of complete depiction were found-NELM (97.8 %; p = 0.008), CRCLM (95.3 %; p = 0.008), and SLM (100 %; p < 0.001). CONCLUSION: DAP-CBCT substantially improved the visibility of liver metastases during IAT. Future studies need to evaluate the clinical impact.