Segmental analysis of aortic basal ring dimensions in normal and dilated tricuspid aortic roots.

OBJECTIVES: In patients with aortic root aneurysm, the aortic basal ring is frequently dilated. It has been speculated that the muscular part of the basal ring dilates most. The purpose of this study was to analyse the segmental dilatation of the basal ring, comparing normal and dilated roots in patients with tricuspid aortic valves. METHODS: Retrospective analysis of computed tomography studies in patients with normal and dilated aortic roots was performed. Lengths of segments of the basal ring corresponding to each of the 3 sinuses, and to the muscular and fibrous parts were measured. Fractions of these segments relative to the total basal ring perimeter were calculated. RESULTS: We analysed 152 normal and 126 dilated aortic roots and 86 propensity-matched pairs. Basal ring dilatation was present in all segments of dilated aortic roots with subtle differences between the segments corresponding to the 3 sinuses. The muscular part of the basal ring dilated proportionately to its fibrous part, with no difference in fractions of measured muscular part in normal and dilated roots [42.2% (interquartile range 4.3%) vs 42.1% (interquartile range 6.3%)]. CONCLUSIONS: Basal ring dilatation was present in all segments corresponding to the 3 sinuses in dilated aortic roots. Both muscular and fibrous parts dilated equally, supporting the need to stabilize the entire basal ring when performing aortic valve repair surgery.

Feasibility of aortic aneurysm sac embolization using a novel shape memory polymer embolic device.

BACKGROUND: We investigated the feasibility of aneurysm sac embolization using a novel self-expanding porous shape memory polymer (SMP) device during endovascular aortic abdominal or thoracic aneurysm repair (EVAR). METHODS: Retrospective analysis of consecutive patients treated at 2 centers in Germany. Patients were treated from January 2019 to July 2021 with follow-up at 7 days and 3, 6, and 12 months. Aneurysm sacs were implanted with SMP devices immediately following endograft placement during the same procedure. Primary endpoint was technically successful SMP-device deployment into the aneurysm sac outside the endograft. Secondary endpoints were changes in aneurysm volume and associated complications (e.g., endoleaks). RESULTS: We included 18 patients (16 males), aged 72 ± 9 years, achieving 100% technical success. Mean preprocedure aortic aneurysm sac volume was 195 ± 117 mL with a perfused aneurysm volume of 97 ± 60 mL. A mean of 24 ± 12 SMP devices per patient were used (range 5-45, corresponding to 6.25-56.25 mL expanded embolic material volume). All evaluable patients exhibited sac regression except 2 patients yet to reach 3-month follow-up. At mean 11 ± 7 months (range 3-24), change in aneurysm volume from baseline was -30 ± 21 mL (p < 0.001). In 8 patients, aneurysm regression was observed despite type 2 endoleaks in 6 and type 1A endoleaks in 2, none of them requiring further intervention to date. No morbidity or mortality related to this treatment occurred. CONCLUSIONS: SMP devices for aortic aneurysm sac embolization during endovascular repair appear feasible and safe in this small case series. Prospective studies are needed. KEY POINTS: • Shape memory polymer is a novel, self-expanding, porous, and radiolucent embolic device material. • Aortic aneurysm sacs were treated with polymer devices immediately following endograft placement. • Aortic aneurysm sac regression was observed in all patients with over 3-month follow-up. • Aortic aneurysm sac regression was observed even in the presence of endoleaks.

Adipose tissue-derived microvascular fragments promote lymphangiogenesis in a murine lymphedema model.

Chronic lymphedema after cancer treatment is common and there is still no cure for this disease. We herein investigated the lymphangiogenic capacity of adipose tissue-derived microvascular fragments (MVF), which contain stem cells and lymphatic vessel fragments. Secondary lymphedema was induced in the hindlimbs of C57BL/6J mice. Green fluorescence protein (GFP)+ MVF were isolated from transgenic C57BL/6Tg (CAG-EGFP)1Osb/J mice, suspended in collagen hydrogel, and injected in the lymphadenectomy defect of wild-type animals. This crossover model allowed the detection of MVF-derived blood and lymphatic vessels after transplantation. The MVF group was compared with animals receiving collagen hydrogel only or a sham intervention. Lymphangiogenic effects were analyzed using volumetry, magnetic resonance (MR) lymphography, histology, and immunohistochemistry. MVF injection resulted in reduced hindlimb volumes when compared to non-treated controls. MR lymphography revealed lymphatic regeneration with reduced dermal backflow after MVF treatment. Finally, MVF transplantation promoted popliteal angiogenesis and lymphangiogenesis associated with a significantly increased microvessel and lymphatic vessel density. These findings indicate that MVF transplantation represents a promising approach to induce therapeutic lymphangiogenesis.

Iatrogenic arterio-biliary fistula and peripheral hepatic artery pseudoaneurysm after transjugular liver biopsy: complication management using a microvascular plug.

This study aimed to report on complication management in a 58-year-old woman referred for transjugular biopsy for the evaluation of unknown liver disease. After an initial uneventful biopsy procedure, the patient complained of severe upper abdominal pain. Laboratory tests revealed increasing liver enzymes. Imaging studies depicted an iatrogenic pseudoaneurysm associated with an arterio-biliary fistula originating from the right peripheral hepatic artery. Angiography and percutaneous transarterial superselective embolotherapy was performed by means of a microcatheter and microvascular plug. Precise device positioning allowed for successful closure of the bleeding site without compromising the hepatic vasculature.

Benefit of including CT urography in [68Ga]PSMA-11 PET/CT with low-dose CT: first results from a larger prostate cancer cohort analysis.

BACKGROUND: Accuracy of [68Ga]PSMA-11 PET/CT may be hampered by ureter accumulation, mimicking lymph node metastases depending on localization and configuration. The benefit of CT urography for differentiation of lymph node metastasis from urinary tract activity was evaluated in a "PET/CT with low-dose CT" setting. METHODS: Retrospective analysis of PET/CT for primary staging, biochemical recurrence or local treatment planning in patients with prostate cancer. For CT urography (CTU), iodinated contrast agent was administered 10 minutes prior to image acquisition. All potential pathologic (peri)ureteral tracer uptake was assigned to excretory ureteral accumulation or pathological lesion. To assess additional provided benefit of CTU all foci were rated with an introduced scoring system (ranging from 0 pts: CTU not needed; up to 3 pts: no differentiation possible without CTU). Success of ureter contrasting was assessed by measurement of Hounsfield units. Besides benefit for reading urography-enhanced PET/CT, the possible impact on subsequent patient treatment was evaluated. RESULTS: A number of N.=247 patients were included in this study. By CT urography, it was possible to identify each ureter on low-dose CT, with its major part contrasted. In 120/247 (48.6%) patients, urography increased the diagnostic confidence while providing substantial support for interpretation in 60 (24.3%) cases. In 42 (17.0%) patients, urography was clinically relevant (up-/downstaging) with potential impact on subsequent patient care. In 30 of these 42 cases (12.1% of all), discrepant treatment would have resulted from a misdiagnosed tracer accumulation without urography. CONCLUSIONS: CT urography benefits the interpretation of [68Ga]-PSMA-11 PET/CT with low-dose CT and leads to discrepant patient treatment in a small but significant subset of patients (12% in our cohort). The implementation of CT urography into standard protocols of [68Ga]PSMA-11 PET/CT with low-dose CT is recommended.

Robotic Salvage Lymph Node Dissection in Recurrent Prostate Cancer: Lessons Learned from 68 Cases and Implications for Future Clinical Management.

PURPOSE: Salvage lymph node dissection is a rescue treatment for patients with nodal recurrence after radical prostatectomy. Very limited data are available on robotic salvage lymph node dissection. Our purpose was to investigate perioperative and oncological outcomes of robotic salvage lymph node dissection in a large monocentric series. MATERIALS AND METHODS: Perioperative data, complications within 30 days after surgery and oncological outcomes as assessed by histology, prostate specific antigen changes, prostate specific antigen nadir after salvage lymph node dissection, and time to further therapy were analyzed. To identify predictive factors for oncological outcome, Kaplan-Meier and Cox-regression analyses were performed. For cases with a mismatch between preoperative positron emission tomography/computed tomography and the number of histologically positive lymph nodes, prostate specific membrane antigen immunohistochemistry was performed on removed lymph nodes. RESULTS: A total of 68 patients underwent robotic salvage lymph node dissection with a median operation time of 126 minutes, a blood loss of 50 ml, and a length of stay of 4 days. No major complications (>Clavien 3) occurred. Median followup was 12.1 months. Median time to further therapy was 12.4 months, 37% of patients experienced complete biochemical response (prostate specific antigen <0.2 ng/ml) and 11% reached an undetectable prostate specific antigen, which was maintained for >1 year in 3 cases. Lower preoperative prostate specific antigen, longer time between radical prostatectomy and salvage lymph node dissection, preoperative prostate specific membrane antigen positron emission tomography/computed tomography and complete biochemical response after salvage lymph node dissection were significant predictors of longer therapy-free survival (all p <0.005). Prostate specific membrane antigen immunohistochemistry revealed that prostate specific membrane antigen positron emission tomography/computed tomography tends to miss small lymph node metastases <5 mm. CONCLUSIONS: Robotic salvage lymph node dissection is a feasible approach with low perioperative morbidity and delays further systemic therapy in most patients. Prostate specific membrane antigen positron emission tomography/computed tomography detection is mostly limited to tumor foci >5 mm.

A 71-Year-Old Man With Chest Pain and a Solitary Pulmonary Mass.

CASE PRESENTATION: A 71-year-old man was admitted to our hospital because of diffuse chest pain and a mass on routine chest radiography. He did not report cough, dyspnea, fever, night sweats, or weight loss. His medical history was remarkable for chronic lymphocytic leukemia diagnosed 13 years before presentation, and secondary myelodysplastic syndrome diagnosed 2 years before the onset of the current symptoms. As a curative approach, he had received a matched unrelated stem cell transplantation 16 months earlier, and he had been in complete remission since. He developed chronic graft-vs-host disease, presenting mainly as oral ulceration (grade 1, according to National Institute of Health consensus criteria), which had been treated with oral cyclosporine and extracorporeal photopheresis. The immunosuppression had been tapered 6 months before presentation. Routine medication included co-trimoxazole prophylaxis twice per week. He had no known allergies, and he denied recent travels and sick contacts.

Jejunal obstruction due to rare internal hernia between skeletonized external iliac artery and vein as late complication of laparoscopic hysterectomy with pelvic lymphadenectomy-case report and review of literature.

BACKGROUND: Internal herniation of small intestine in the lesser pelvis alongside iliac vasculature is a rare occurrence. Skeletonization of iliac vessels during pelvic lymph node dissection (LND), as part of surgical staging or treatment of patients with uterine, ovarian or urogenital cancer, is a strict prerequisite for orifice formation. CASE PRESENTATION: A 68-year-old woman presented at the emergency department with complaints of constipation for the last 3 days and acute-onset abdominal pain, nausea and vomiting since few hours. She had a history of laparoscopic hysterectomy, bilateral salpingo-oophorectomy and para-aortic and pelvic LND 7 years ago. A distended abdomen with diffuse tenderness on palpation was noted. A CT scan demonstrated bowel obstruction secondary to an incarcerated hernia underneath an elongated right external iliac artery. During an emergency exploratory laparotomy, the incarcerated bowel was reduced and the hernial orifice closed with a running suture. The patient had an uneventful postoperative period and was discharged on the fifth postoperative day. DISCUSSION: This rare internal hernia can manifest with non-specific symptoms of small bowel obstruction at any given point after index surgery, sometimes even after several years free of complaints. Contrast-enhanced computed tomography is the method of choice for fast and reliable diagnosis and helps in planning the necessary emergency laparotomy. CONCLUSION: This life-threatening complication adds to the current controversy of pelvic and para-aortic lymphadenectomy in patients with endometrial cancer. Primary closure of peritoneal defects should be considered to potentially prevent internal hernias, especially when elongated iliac vessels are present.

Radiation dose of chaperones during common pediatric computed tomography examinations.

BACKGROUND: One main challenge in pediatric imaging is to reduce motion artifacts by calming young patients. To that end, the Radiological Society of North America (RSNA) as early as 1997 stated the necessity of adults accompanying their child during the child's examination. Nonetheless, current research lacks data regarding radiation dose to these chaperones. OBJECTIVE: The aim of this study was to measure the radiation dose of accompanying adults during state-of-the-art pediatric CT protocols. MATERIALS AND METHODS: In addition to a 100-kV non-contrast-enhanced chest CT (Protocol 1), we performed a 70-kV contrast-enhanced chest protocol (Protocol 2) using a third-generation dual-source CT. We acquired data on the radiation dose around the scanner using digital dosimetry placed right at the gantry, 1 m away, as well as beside the gantry. We acquired the CT-surrounding radiation dose during scanning of a pediatric phantom as well as 12 pediatric patients. RESULTS: After conducting 10 consecutive phantom scans using Protocol 1, we found the location with the highest cumulative dose acquired was right next to the gantry opening, at 3 µSv. Protocol 2 showed highest cumulative dose of 2 µSv at the same location. For Protocol 1, the location with the highest radiation doses during pediatric scans was right next to the gantry opening, with doses of 0.75±0.70 µSv. For Protocol 2, the highest radiation was measured 1 m away at 0.50±0.60 µSv. No radiation dose was measured at any time beside the gantry. CONCLUSION: Our results provide proof that chaperones receive low radiation doses during state-of-the-art CT examinations. Given knowledge of these values as well as the optimal spots with the lowest radiation doses, parents as well as patients might be more relaxed during the examination.

Life-threatening arterioureteral fistula treatment by endovascular complete anatomic iliac artery bifurcation reconstruction.

We present an endovascular approach for anatomic reconstruction of the iliac bifurcation in life-threatening arterioureteral fistula without sacrificing the pelvic arterial vascular supply. Five consecutive patients suffering from acute onset of significant gross hematuria caused by iliac-ureteral fistula resulting from previous oncologic surgery and radiation therapy were treated by transfemoral stent graft implantation in a double-barrel technique. Iliac-ureteral pseudoaneurysm coverage succeeded in an iliac neobifurcation with preservation of pelvic perfusion. Follow-up ranging from 9 to 37 months confirmed cessation of hematuria. One patient experienced stent graft thrombosis of the external iliac artery as a result of large cervical cancer invasion treated by crossover bypass. In all other patients, stent grafts were patent.

Evaluation of Gadopiclenol and P846, 2 High-Relaxivity Macrocyclic Magnetic Resonance Contrast Agents Without Protein Binding, in a Rodent Model of Hepatic Metastases: Potential Solutions for Improved Enhancement at Ultrahigh Field Strength.

PURPOSE: The aim of this study was to evaluate in vitro and in vivo the enhancement properties of experimental gadolinium (Gd)-based contrast agents (GBCAs) with different molecular weights and hydration numbers (P846 and gadopiclenol) compared with clinically approved low-molecular, extracellular agents (gadopentetate and gadoterate) at 9.4 T and to discuss influencing factors on r1 relaxivities. METHODS AND MATERIALS: All experiments were performed with a 9.4 T animal scanner (Bruker, Germany). We performed relaxometry measurements for all contrast agents in human plasma at 37°C using an IR-RARE sequence. In addition, we compared P846 with gadopentetate and gadopiclenol with gadoterate intraindividually in rats with hepatic colorectal cancer metastases (n = 10 each) acquiring T1-weighted FLASH sequences before and at 10 consecutive time points during 20 minutes. After intravenous contrast agent application, signal-to-noise ratios (SNRs), contrast-to-noise ratios (CNRs), and lesion enhancement (LE) for liver parenchyma and tumors were calculated based on region of interest measurements. RESULTS: Longitudinal relaxivities (r1) of the low-molecular agents were lower as compared with the experimental compounds. However, r1 of gadopentetate and gadoterate demonstrated only a moderate decrease of r1 at 9.4 T as compared with known data at lower field strengths (gadopentetate: r1 [at 9.4 T], 3.4 mM s/r1 [at 1.5 T], 4.1 mM s/gadoterate: r1 [at 9.4 T], 3.1 mM s/r1 [at 1.5 T], 3.6 mM s). In contrast, r1 of P846 showed a marked reduction at 9.4 T compared with 1.5 T (P846: r1 [at 9.4 T], 6.4 mM s/r1 [at 1.5 T], 32 mM s). Gadopiclenol provided the highest r1 in this study at 9.4 T and the drop of r1 as compared with lower field strength is less apparent (gadopiclenol: r1 [at 9.4 T], 8.7 mM s/r1 [at 1.5 T], 12.7 mM s).In vivo, P846 and gadopiclenol showed significantly higher SNR, CNR, and LE as compared with the low-molecular control agents (mean ± SD; SNRliver [gadopentetate, 18.1 ± 1.2; P846, 27.2 ± 1.5; P < 0.001]; SNRtumor [gadopentetate, 22.6 ± 1.9; P846, 40.1 ± 1.9; P < 0.001]; CNR [gadopentetate, 4.6 ± 1.0; P846, 12.9 ± 0.9; P < 0.001]; LE [gadopentetate, 7.2 ± 1.9; P846, 14.9 ± 1.9; P < 0.001]/SNRliver [gadoterate, 8.8 ± 0.5; gadopiclenol, 12.6 ± 1.3; P < 0.001]; SNRtumor [gadoterate, 11.3 ± 1.2; gadopiclenol, 20.9 ± 2.9; P < 0.001]; CNR [gadoterate, 2.5 ± 0.7; gadopiclenol, 8.3 ± 1.7; P < 0.001]; LE [gadoterate, 4.4 ± 1.2; gadopiclenol, 13.0 ± 2.9; P < 0.001]). Thus, for equal Gd doses, gadopiclenol and P846 increase the CNR of liver metastases by a factor of 2.5 to 3 at 9.4 T compared with gadoterate and gadopentetate. CONCLUSIONS: P846 and gadopiclenol provide superior enhancement at 9.4 T as compared with gadopentetate and gadoterate. However, the macromolecular agent P846 shows a marked decrease of r1 from 1.5 T to 9.4 T. This effect is less apparent for the low-molecular agents gadopiclenol, gadopentetate, and gadoterate. Yet, based on the higher hydration number, r1 of P846 and gadopiclenol are markedly higher as compared with the reference contrast agents. Thus, building compounds with moderately increased molecular size and hydration number, as implemented in gadopiclenol, seems to be a promising way to develop highly effective GBCAs.Advantages for gadopiclenol include a strong enhancement regardless of the external magnetic field strength, pharmacokinetics comparable to those of clinically approved extracellular GBCAs, and the potential to either improve sensitivity in diagnostic magnetic resonance imaging by improving lesion conspicuity or to perform studies with significantly reduced Gd-dose while at the same time providing comparable diagnostic accuracy. However, all this needs to be proven in clinical studies.

Percutaneous endovascular tissue sampling of endoluminal tumors using directional atherectomy.

OBJECTIVES: To evaluate technical feasibility and safety of endovascular tumor specimen sampling using an escalating endovascular biopsy strategy using a directional atherectomy device compared with forceps biopsy and catheter aspiration. MATERIALS AND METHODS: Between 2013 and 2017, a cohort of ten consecutive patients (6 male; median age 56, range 39-73 years) was referred for sampling of endovascular masses. Localizations included the abdominal aorta (n = 4), left brachiocephalic vein (n = 2), inferior vena cava (n = 1), and left pulmonary artery (n = 3). For each individual mass, all three endovascular tissue sampling approaches were applied including catheter-based aspiration, straight two-jaw biopsy forceps, and directional atherectomy during a single session. RESULTS: Aspiration and forceps biopsy did not provide sufficient material for histological analyses. In contrast, technical success for endovascular tumor sampling using directional atherectomy was 100%. After two atherectomy passages, sufficient material was available for each vessel region allowing histologic diagnosis, which revealed sarcoma and chronic inflammation for masses in the aorta, angiosarcoma for brachiocephalic vein, hepatocellular carcinoma for inferior vena cava, and angiosarcoma for pulmonary artery. In case of a histologically benign diagnosis, no malignant tumor proliferation was obvious on follow-up imaging studies after 3 months and 1 year. Thus, the rate of false-negative results was considered 0%. No procedure-associated complications, e.g., vessel perforation, were recorded. CONCLUSION: Preliminary results in a limited number of patients proved directional atherectomy beneficial as a safe and feasible technique for endoluminal tissue sampling of vascular masses. Additional large-scale studies are necessary and worthy for further evaluation in clinical practice. KEY POINTS: • Endovascular masses pose a challenge to appropriate clinical management. • Off-label directional atherectomy proved to be a safe and feasible technique for endoluminal tissue sampling of vascular masses. Furthermore, directional atherectomy was superior to aspiration or forceps biopsy in our small study cohort. • Directional atherectomy may represent the last or only option for tissue probing as a prerequisite for further treatment decisions.

AGuIX® from bench to bedside-Transfer of an ultrasmall theranostic gadolinium-based nanoparticle to clinical medicine.

AGuIX® are sub-5 nm nanoparticles made of a polysiloxane matrix and gadolinium chelates. This nanoparticle has been recently accepted in clinical trials in association with radiotherapy. This review will summarize the principal preclinical results that have led to first in man administration. No evidence of toxicity has been observed during regulatory toxicity tests on two animal species (rodents and monkeys). Biodistributions on different animal models have shown passive uptake in tumours due to enhanced permeability and retention effect combined with renal elimination of the nanoparticles after intravenous administration. High radiosensitizing effect has been observed with different types of irradiations in vitro and in vivo on a large number of cancer types (brain, lung, melanoma, head and neck…). The review concludes with the second generation of AGuIX nanoparticles and the first preliminary results on human.

The first post-cardiac injury syndrome reported following transcatheter aortic valve implantation: a case report.

BACKGROUND: Post-cardiac injury syndrome is a form of secondary pericarditis with or without pericardial effusion, which typically occurs weeks to months following an injury to the heart or pericardium. Disease activity can be followed with serial testing of inflammatory markers e.g. C-reactive protein (CRP) and/or sedimentation rate, electrocardiogram, and echocardiography. CASE SUMMARY: A 79-year-old woman was admitted with chest pain, dyspnoea at rest, cough, and low degree fever. The patient had undergone transcatheter aortic valve implantation (TAVI) 6 months before admission. Inflammatory markers were increased and a chest X-ray and computed tomography (CT) showed a minimal left pleural effusion. An empirical antibiotic treatment and ibuprofen to control chest pain were started on the presumption of an acute bronchitis. Despite 15 days of different antibiotic protocols the markers of inflammation remained increased. A positron emission tomography with computed tomography and cardiac magnetic resonance imaging showed signs of an aseptic pericarditis. After having excluded any infectious, metabolic, drug-induced or neoplastic genesis we considered the diagnosis of late onset autoimmune-mediated pericarditis. Subsequently, treatment was promptly initiated with colchicine and prednisone. The patient reported clinical improvement in the following days and the CRP value continuously decreased. DISCUSSION: To the best of our knowledge, this is the first reported case of post-cardiac injury syndrome after TAVI. It should be considered in those patients who have persistent chest pain, fever, fatigue, and elevated inflammatory markers after a TAVI procedure, even though it may occur weeks or months after the intervention. A triple therapy with colchicine, ibuprofen, and low-dosage steroids may be used for persistent symptoms.

Fleckenstein's hypothesis revisited: excessive myocardial calcification after prolonged high dose catecholamine treatment: a case report.

BACKGROUND: Myocardial calcification after prolonged highly dosed catecholamine treatment has been described experimentally. Here, we demonstrate myocardial calcifications by high-dose catecholamine treatment leading to chronic heart failure in patients. CASE SUMMARY: A 62-year-old Caucasian woman presented with central pulmonary embolism, developing acute heart failure, and cardiogenic shock. Twenty-six days of high-dose norepinephrine treatment had to be administered to maintain circulation. After 74 days of intensive care treatment, the patient fortunately recovered but was readmitted to emergency ward because of dyspnoea and congestion. Computed tomography pulmonary angiography ruled out recurrence of pulmonary embolism, but depicted massive intramural cardiac calcifications, which were not present before treatment. Coronary angiography showed normal coronary arteries, and myocardial biopsy excluded infectious myocarditis. There was no evidence for sarcoidosis, thyroid disease, tuberculosis, or hyperparathyroidism. Oral heart failure treatment was initiated and at the 7 week follow-up the patient remained symptomatic with New York Heart Association functional Class III, while right and left ventricular function had recovered. DISCUSSION: Prolonged activation of the heart by catecholamines leading to myocardial calcifications has first been examined experimentally by Fleckenstein et al. Herein, we are able to show, that this can occur in clinical situations. Careful dosing of catecholamines and early use of non-catecholamine-based haemodynamic support is recommended to avoid consecutive impairment of heart function and heart failure.

Cardiac Computed Tomography as an Imaging Modality in Coronary Anomalies.

Coronary artery fistulae and coronary aneurysms are rare anomalies. When they become symptomatic, they require precise anatomic information to allow for planning of the therapeutic procedure. We report a case in which both fistulae and aneurysm were present. The required information could only be obtained by electrocardiogram-gated computed tomography with reformation. This imaging modality should be considered in every case of fistula or coronary aneurysm.

Organ-Preserving Surgical Treatment of a Horseshoe Kidney Occupied by a Large Renal Cell Carcinoma with Extensive Venous Invasion: A Case Report.

The horseshoe kidney is one of the most common congenital disorders affecting the urogenital system. Following a fusion of the lower kidney poles, which in turn lead to the formation of an isthmus, this anatomical variation is accompanied by other characteristic properties like an incomplete ascension, ventral rotation of the pelvices as well as atypical vascular supply. Even though renal carcinoids and Wilms tumors are more common in horseshoe kidneys, the incidence of renal cell carcinomas seems to be unaffected. Here we report the case of a locally advanced renal cell carcinoma with extensive venous invasion occurring in a horseshoe kidney and its complex surgical management. The whole primary tumor as well as a majority of venous tumor thrombi could be removed by a combination of 2/3 nephrectomy and cavotomy with thrombectomy. During 1 year of follow-up, the patient neither suffered from a tumor relapse, nor did he require renal replacement therapy. Thus, we conclude that even in cases of RCC where advanced disease is associated with complex anatomical situations, organ-preserving surgical treatment should be pursued to achieve excellent functional and oncological results.

Three-dimensional ultrashort echo time MRI and Short T2 images generated from subtraction for determination of tumor burden in lung cancer: Preclinical investigation in transgenic mice.

PURPOSE: To investigate the potential of 3D ultrashort echo time MRI and short T2 images generated by subtraction for determination of total tumor burden in lung cancer. METHODS: As an animal model of spontaneously developing non-small cell lung cancer, the K-rasLA1 transgenic mouse was used. Three-dimensional MR imaging was performed with radial k-space acquisition and echo times of 20 µs and 1 ms. For investigation of the short T2 component in the recorded signal, subtraction images were generated from these data sets and used for consensus identification of tumors. Next, manual segmentation was performed on all MR images by two independent investigators. MRI data were compared with the results from histologic investigations and among the investigators. RESULTS: Tumor number and total tumor burden from imaging experiments correlated strongly with the results of histologic investigations. Intra- and interuser comparison showed highest correlations between the individual measurements for ultra-short TE MRI. CONCLUSIONS: Three-dimensional MRI protocols facilitate accurate tumor identification in mice harboring lung tumors. Ultrashort TE MRI is the superior imaging strategy when investigating lung tumors of miscellaneous size with 3D MR imaging strategies. Magn Reson Med 79:1052-1060, 2018. © 2017 International Society for Magnetic Resonance in Medicine.