RepoMed (Medizinische Hochschule Hannover)
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The impact of the COVID-19 pandemic on women seeking fertility treatment in Germany: the patient´s perspective
Get PDFQuantitative assessment of ablation zone accuracy in 3D stack-of-spirals proton resonance frequency shift thermometry during clinical hepatic microwave ablation
Get PDFIntroduction Real-time temperature feedback is critical for hepatic tumor ablation. Volumetric MR PRFS thermometry, including 3D stack-of-spirals sequences, shows promise; however, clinical validation for microwave ablation (MWA) is lacking. This study evaluated feasibility, spatial accuracy and susceptibility-related artifacts during hepatic MWA. Methods In 24 consecutively treated patients, 48 ablations targeting 34 hepatic lesions were included. After excluding 12 patients with overlapping ablations and one with severe artifacts, a retrospective analysis was conducted in 11 patients with 15 lesions. Thermometry-derived ablation zones were compared with post-ablative contrast-enhanced segmented ground truth. Spatial accuracy was quantified by Dice score (DS), sensitivity and mean surface distance (MSD) for full volumes and central five slices (1.25 cm) orthogonal to B0. Volumetric agreement was assessed by Pearson correlation. Voxel-wise temperature stability in unheated liver, needle orientation relative to B0 and capsule distance were correlated with ablation precision metrics. Results Unheated tissue temperature SD was 1.69 ± 0.51 °C. Mean full-volume accuracy was DS 0.64 ± 0.07, sensitivity 0.71 ± 0.11, MSD 3.91 mm ± 1.32 mm; mid-slice metrics yielded DS 0.75 ± 0.06, sensitivity 0.88 ± 0.08, MSD 4.33 mm ± 1.50 mm (all p < 0.001). DS correlated negatively with temperature SD (r = -0.61) and positively with capsule distance (r = .75); MSD showed inverse patterns. Needle orientation bore no significant correlation. Thermometry and ground truth volumes correlated strongly (r = 0.87). Conclusion Clinical 3D stack-of-spirals PRFS thermometry enables feasible volumetric and spatial estimation during hepatic MWA, though residual deviations remain. Central slices approach clinically relevant precision despite susceptibility effects. Targeted correction strategies and faster reconstruction may enable reliable real-time thermometry for guiding and validating thermal therapies in the abdomen
Identifikation von Prädiktoren des Therapieansprechens auf eine Prostata-spezifisches Membranantigen (PSMA)-Radioligandentherapie bei Patienten mit metastasiertem kastrationsresistenten Prostatakarzinom
Get PDFMultimodality molecular imaging of heart-kidney axis in cardiovascular disease: evaluating hypertension-induced heart failure and impact on kidney
Get PDFCharakterisierung von Astrozyten bei De- und Remyelinisierung in dem toxischen Cuprizone-Tiermodell für Multiple Sklerose
Get PDFIdiopathic inflammatory myopathy associated with Sjögren’s disease: features of a distinct clinical entity
Get PDFBackground: Idiopathic inflammatory myopathies (IIM) and Sjögren’s disease (SjD) may coexist, but data on their combined presentation and treatment response remain limited. Methods: We retrospectively analyzed 23 patients with biopsy-confirmed IIM and coexisting SjD, compared to 24 age- and sex-matched IIM controls without SjD. Clinical, electrophysiological, and immunological data, as well as treatments and outcomes, were assessed. Outcome assessment included EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI) and the ACR/EULAR Myositis Response Criteria for adult polymyositis and dermatomyositis. Results: Among IIM-SjD patients, 39% had inclusion body myositis (IBM), 61% had poly- or dermatomyositis. Compared to controls, asymmetric muscle weakness (78%, p=0.0012), non-muscular manifestations (52%, p=0.0035), and more immunosuppressive therapies (median 3; p=0.0253), including more frequent anti-CD20 use (30%, p=0.0039) were found in IIM-SjD. After a median follow-up of 80 months, patients showed better outcomes (lower ESSDAI and higher ACR/ EULAR response scores; p=0.0031 and p=0.0083). IBM was a strong predictor of higher ESSDAI scores at follow-up (p=0.014). Conclusions: The study suggests that IIM-SjD is characterized by more asymmetric muscle weakness and extramuscular involvement. Enhanced immunosuppression led to better outcomes in patients with poly- or dermatomyositis, while IBM was linked to higher disease activity. Further research is needed to clarify underlying mechanisms
App-based daily self-measurement of impedance in cochlear implant users
Get PDFIntroduction Impedance telemetry measurements in cochlear implant (CI) recipients are commonly used to assess CI electrode functionality and provide valuable insights into inner ear conditions. However, these measurements usually take place only during surgery and at clinical follow-up appointments, offering limited temporal resolution of impedance changes. This study aimed to address this gap by implementing daily impedance monitoring using a smartphone app. Methods A prospective study evaluated the usability of a research app for remote impedance measurements over 4 months following standard CI surgery with a MED-EL FLEX28 electrode. Impedance was recorded twice daily (morning and evening). The mean impedance across all electrode channels was analyzed for four postoperative time periods: early postoperative (up to day 10 postoperatively), late postoperative (from day 11 to ~4 weeks), intensive fitting (from ~4 weeks postoperatively to ~7 weeks) and regular hearing phase (from ~7 weeks to 4 months). Two CI fitting approaches were compared: activation during the early postoperative phase (early activation, EA) and activation during the intensive fitting phase (conventional activation, CA). Morning-to-evening differences in impedance (MED) were also examined. Results The app demonstrated an overall usage rate of 66% (n = 28), indicating moderate-to-high adherence. Except for higher evening impedance values with CA in the late postoperative phase, no significant differences in mean impedance between the fitting approaches were observed (EA: 6.46 kΩ, n = 11; CA: 7.82 kΩ, n = 11; p = 0.04). Significant differences in MED were found during the early postoperative phase (EA: 0.06 kΩ, n = 8; CA: -0.18 kΩ, n = 10; p = 0.04) and the late postoperative phases (EA: 0.85 kΩ, n = 11; CA: 0.03 kΩ, n = 11; p < 0.001). Conclusion Remote impedance measurements via the app can be made over an extended postoperative period. The increased measurement frequency allowed for detailed characterization of impedance dynamics, particularly around the onset of electrical stimulation. No clinically relevant difference in mean impedance was found between EA and CA groups. Daily fluctuations showed consistently lower evening values after stimulation onset. These findings highlight the potential value of this approach for enhancing postoperative CI management
