Comparison of a new MR rapid wash-out map with MR perfusion in brain tumors.

BACKGROUND: MR perfusion is a standard marker to distinguish progression and therapy-associated changes after surgery and radiochemotherapy for glioblastoma. TRAMs (Treatment Response Assessment Maps) were introduced, which are intended to facilitate the differentiation of vital tumor cells and radiation necrosis by means of late (20-90 min) contrast clearance and enhancement. The differences of MR perfusion and late-enhancement are not fully understood yet. METHODS: We have implemented and established a fully automated creation of rapid wash-out (15-20 min interval) maps in our clinic. We included patients with glioblastoma, CNS lymphoma or brain metastases who underwent our MR protocol with MR perfusion and rapid wash-out between 01/01/2024 and 30/06/2024. Since both wash-out and hyperperfusion are intended to depict the active tumor area, this study involves a quantitative and qualitative comparison of both methods. For this purpose, we volumetrically measured rCBV (relative cerebral blood volume) maps and rapid wash-out maps separately (two raters). Additionally, we rated the agreement between both maps on a Likert scale (0-10). RESULTS: Thirty-two patients were included in the study: 15 with glioblastoma, 7 with CNS lymphomas and 10 with brain metastasis. We calculated 36 rapid wash-out maps (9 initial diagnosis, 27 follow-up). Visual agreement of MR perfusion with rapid wash-out by rating were found in 44 ± 40% for initial diagnosis, and 75 ± 31% for follow-up. We found a strong correlation (Pearson coefficient 0.92, p < 0.001) between the measured volumes of MR perfusion and rapid wash-out. The measured volumes of MR perfusion and rapid wash-out did not differ significantly. Small lesions were often not detected by MR perfusion. Nevertheless, the measured volumes showed no significant differences in this small cohort. CONCLUSIONS: Rapid wash-out calculation is a simple tool that provides new information and, when used in conjunction with MR perfusion, may increase diagnostic accuracy. The method shows promising results, particularly in the evaluation of small lesions.

Calculation of virtual 3D subtraction angiographies using conditional generative adversarial networks (cGANs).

OBJECTIVE: Subtraction angiographies are calculated using a native and a contrast-enhanced 3D angiography images. This minimizes both bone and metal artifacts and results in a pure image of the vessels. However, carrying out the examination twice means double the radiation dose for the patient. With the help of generative AI, it could be possible to simulate subtraction angiographies from contrast-enhanced 3D angiographies and thus reduce the need for another dose of radiation without a cutback in quality. We implemented this concept by using conditional generative adversarial networks. METHODS: We selected all 3D subtraction angiographies from our PACS system, which had performed between 01/01/2018 and 12/31/2022 and randomly divided them into training, validation, and test sets (66%:17%:17%). We adapted the pix2pix framework to work on 3D data and trained a conditional generative adversarial network with 621 data sets. Additionally, we used 158 data sets for validation and 164 for testing. We evaluated two test sets with (n = 72) and without artifacts (n = 92). Five (blinded) neuroradiologists compared these datasets with the original subtraction dataset. They assessed similarity, subjective image quality, and severity of artifacts. RESULTS: Image quality and subjective diagnostic accuracy of the virtual subtraction angiographies revealed no significant differences compared to the original 3D angiographies. While bone and movement artifact level were reduced, artifact level caused by metal implants differed from case to case between both angiographies without one group being significant superior to the other. CONCLUSION: Conditional generative adversarial networks can be used to simulate subtraction angiographies in clinical practice, however, new artifacts can also appear as a result of this technology.

Open reduction and internal fixation of acetabular fractures in patients of old age.

MATERIAL AND METHODS: There is an ongoing debate on which treatment for acetabular fractures in elderly patients is the most appropriate. This study was set up to identify the role of open reduction and internal fixation of acetabular fractures in persons of old age. We retrospectively reviewed the medical charts and radiological data of all patients older than 65 years, who suffered an isolated acetabular fracture and were admitted in our Department between 2010 and 2014 (5-year period). Complications, outcome and mortality were recorded. Of all surviving patients, quality of life (QoL), mobility and independence were graded with European Quality of Life 5 Dimensions 3 Level (EQ-5D-3L), European Quality of Life 5 Dimensions Visual Analogue Scale (EQ-5D-VAS), Numeric Rating Scale (NRS), Elderly Mobility Scale (EMS) and Tinetti Mobility Test (TMT). RESULTS: Seventy patients could be identified. There were 52 men (74%) and 18 women (26%) with a median age of 79.0 years (range: 65-104 years). Forty-six patients (66%) had been treated with open reduction and internal fixation (ORIF), 24 (34%) conservatively. There were negative predictive factors-subchondral impaction, damage to the femoral head and multiple fragments-in 54% of the operative group. With ORIF, an anatomical reduction could be achieved in 27 patients (59%), an acceptable in 18 (39%) and a poor in one (2%). At follow-up, 18 patients (26%) had died and 23 (33%) were not able to participate. The follow-up rate of the surviving operatively treated patients was 77%. Eleven of 46 operated patients (24%) needed a conversion to a total hip arthroplasty (THA). All patients undergoing conversion had imperfect reduction after surgery. No patient in the non-operative group underwent conversion to THA during follow-up. The median follow-up time of operatively treated patients without conversion (n = 17) was 30 months (range, 16-73 months), of patients with THA (n = 9) 30 months after conversion (range, 17-55 months). Quality of reduction correlated to QoL, mobility and independence in all recorded parameters. Patients with secondary THA had similar good outcomes as patients after ORIF without later conversion. Men had better outcome than women. CONCLUSION: ORIF of acetabular fractures in patients of old age results in excellent outcomes at short-term follow-up when anatomical reduction can be achieved. In case of negative predictive factors, ORIF cannot be regarded as a definitive solution, rather as the construction of a stable socket for secondary THA. The decision of therapy should be made dependent on pre-operative radiographic parameters.

The DERIVO 2 Heal Embolization Device in the Treatment of Ruptured and Unruptured Intracranial Aneurysms: a Retrospective Multicenter Study.

BACKROUND: The use of flow diverting stents in the treatment of intracranial aneurysms is associated with a risk of neurological morbidity due to their thrombogenicity. To reduce this risk different surface modifications have been developed. The Derivo 2 Embolization Device (Acandis, Pforzheim, Germany) has proven to be a safe and effective flow diverter. To overcome the risk of thrombo-embolism, the device was modified by adding an anti-thrombogenic fibrin-heparin coating. We aimed to assess the safety and effectiveness of the Derivo 2 heal Embolization Device. METHODS: Retrospective multicenter data from nine German neurovascular centers between February 2022 until December 2023 were used. Patients treated with the Derivo 2 heal Embolization Device for unruptured or ruptured intracranial aneurysms were included. Peri- and postprocedural adverse events, clinical outcomes, and angiographic follow-up results were evaluated. RESULTS: 84 patients (73.8% female; mean age 58.7 years) with 89 aneurysms (mean size 9.8 mm) were included. 87.6% were located in the anterior circulation. Most of them were sidewall aneurysms (88.8%). 96 flow diverters were used. 99.0% were successfully implanted. An in-stent balloon angioplasty was performed in 6.0% of the cases. An additional coiling was performed in 28.6%. Technical difficulties were present in 12.0% of the cases. Thrombotic events occurred in 4.8% with no neurological sequelae. Mortality and morbidity were 0 and 1.2% respectively. Adequate aneurysm occlusion was achieved in 80.7% with a mean follow-up time of 6.6 months. CONCLUSION: The Derivo 2 heal Embolization Device showed a satisfying aneurysm occlusion and safety with a low rate of neurological morbidity.

The interleukin-11 receptor variant p.W307R results in craniosynostosis in humans.

Craniosynostosis is characterized by the premature fusion and ossification of one or more of the sutures of the calvaria, often resulting in abnormal features of the face and the skull. In cases in which growth of the brain supersedes available space within the skull, developmental delay or cognitive impairment can occur. A complex interplay of different cell types and multiple signaling pathways are required for correct craniofacial development. In this study, we report on two siblings with craniosynostosis and a homozygous missense pathogenic variant within the IL11RA gene (c.919 T > C; p.W307R). The patients present with craniosynostosis, exophthalmos, delayed tooth eruption, mild platybasia, and a basilar invagination. The p.W307R variant is located within the arginine-tryptophan-zipper within the D3 domain of the IL-11R, a structural element known to be important for the stability of the cytokine receptor. Expression of IL-11R-W307R in cells shows impaired maturation of the IL-11R, no transport to the cell surface and intracellular retention. Accordingly, cells stably expressing IL-11R-W307R do not respond when stimulated with IL-11, arguing for a loss-of-function mutation. In summary, the IL-11R-W307R variant, reported here for the first time to our knowledge, is most likely the causative variant underlying craniosynostosis in these patients.

Reopening the Bavarian State Opera Safely: Hygiene Strategies and Incidence of COVID-19 in Artistic Staff During Theater Season 2020/2021.

Due to the drastically rising coronavirus disease (COVID-19) incidence since March 2020, social life was shut down across the globe, and most opera houses were closed. As a result, there are limited data on SARS-CoV-2 infections among artists. The Bavarian State Opera has been reopened in September 2020. This study aimed to identify the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among employees in the Bavarian State Opera. In addition, the various hygiene strategies for the work groups within the institution are described. During the study period from September 1, 2020 to July 31, 2021, 10,061 nasopharyngeal swabs were obtained from 1,460 artistic staff members in a rolling system. During the entire study period, 61 individuals tested positive for SARS-CoV-2. None of the patients had a severe disease course. Compared to the seven-day-incidence per 100,000 German inhabitants, the estimated corresponding incidence among employees was lower at 37 weeks and higher or equal at 9 weeks. Among the infected individuals, 58.3% were symptomatic, 23.3% were presymptomatic, and 18.3% were asymptomatic. Forty-five percent of employees reported that they had been infected in their private environment, 41.7% suspected that their colleagues were the main contact, and 13.3% were unsure about the origin of their infection. Twenty-four diseased employees were ballet dancers, eight from the orchestra, seven from the administration, seven from the choir singers, six from the costume department, 10 from technical support, and one guest solo singer. In the 2020/2021 theater season, increased SARS-CoV-2 infections and large disease outbreaks were avoided at the Bavarian State Opera. Hygiene strategies, that existed since the beginning, was specifically designed for various work areas in the opera. Regular, mandatory PCR testing and follow-up of positive cases with the issuance of quarantine were performed. Using this disease management approach, artistic work at and reopening of the Bavarian State Opera was feasible with a well-controlled risk.