Dirk Lehnick

Introduction: Negative experiences during mammography can reduce patient’s adherence. Yet patient reported measures focusing on the diagnostic pathway remain limited, particularly in general radiology departments that are not specialized in breast imaging only. This prospective study evaluated the overall patient satisfaction with digital mammography (DM) using a tailored patient reported experience measure (PREM) and examined associations with personal, clinical, and procedural factors to identify actionable quality assurance targets. Materials and methods: Women undergoing DM or digital breast tomosynthesis for screening, surveillance, follow up of high-risk lesions, or diagnostic clarification at a medium sized general hospital were recruited between February and July 2023. Of 885 eligible women, 549 (62%) aged 29-88 years completed a validated 23 item PREM questionnaire. Associations between satisfaction and personal (age, anxiety, pain), clinical (breast density, cancer history), and procedural factors (radiographer communication, radiologist consultation) were assessed using Fisher’s exact test, Kendall’s tau b correlations, and ordered logistic regression. Significance was set at p < 0.05. Free text comments were analyzed using IRaMuTeQ to identify thematic clusters. Results: Overall, 78% (428/549) of participants reported full satisfaction with DM. Satisfaction was significantly related to personal and procedural factors (p < 0.05), particularly anxiety (τb = −0.2), pain (τb = −0.3), age (τb = 0.1), radiographer communication (τb = 0.3), and efforts to reduce discomfort (τb = 0.4). Consultations with a breast radiologist immediately after DM markedly increased the likelihood of full satisfaction (+14 percentage points). In contrast, clinical variables, including breast cancer history, breast density, and familial risk, showed no significant association with satisfaction (p > 0.05). Free text analysis revealed four influencing dominant themes: waiting time before radiologist consultation, staff competence, gratitude toward radiographers and radiologists, and the physical environment of examination rooms. Conclusion: Patient satisfaction with DM in a nonspecialized general radiology department is predominantly shaped by modifiable procedural and interpersonal factors rather than clinical factors. Radiographers’ communication and efforts to reduce discomfort emerged as key determinants of satisfaction, alongside immediate result communication by radiologists. PREMs are feasible to implement in routine breast imaging workflows and offer valuable insights for quality assurance and patient centered optimization of mammography services. Clinical relevance statement: Systematically measuring women’s experiences using PREMs helps identify practical improvement targets, such as communication quality, workflow design, and timely result disclosure, that may enhance patient satisfaction, reduce anxiety, and potentially increase adherence to breast cancer imaging recommendations.

Background/Objectives: This study evaluated the clinical image quality of three-dimensional synthetic MRI (3D SI) compared with conventional MRI (cMRI), focusing on tissue contrast, anatomical detail, and motion sensitivity. Methods: Patients with nonspecific neurological symptoms were included. Both cMRI and 3D SI were acquired on single-vendor 1.5 T and 3 T scanners with slice thicknesses of 1.0–1.7 mm. Two experienced neuroradiologists and one fellow independently evaluated matched scans using a 0–100 scale. Assessed parameters included signal-to-noise ratio (SNR), gray–white matter contrast, artifacts, motion robustness, and confidence in detecting perivascular spaces, white matter lesions, and subtle pathology. Interrater agreement was measured using Krippendorff’s alpha and ICC2. Multiple linear regression analyzed associations between image quality ratings and imaging method. Results: Images of 31 patients were analyzed. Three-dimensional SI demonstrated sufficient-to-good overall image quality and high robustness to motion. Cortical-surface-to-cerebrospinal-fluid contrast on FLAIR was rated lower for 3D SI than for cMRI. False-positive lesion detection occurred more frequently on 3D SI FLAIR, particularly among experienced readers. cMRI achieved significantly higher T1-weighted SNR than 3D SI (8.76 points, p < 0.001). Experienced readers consistently rated SNR and tissue contrast higher than the fellow. Vascular signal range was broader on 3D SI, reducing sensitivity to vascular abnormalities. Conclusions: Three-dimensional synthetic MRI provides clinically usable image quality and fulfills its primary diagnostic purpose, offering advantages in acquisition efficiency and robustness to motion. Nevertheless, limitations in cortical contrast, vascular signal characterization, and reader-dependent interpretive variability constrain its reliability for subtle or detail-critical findings.

Background: Simulation-based training may offer a useful approach to support skill acquisition in neurointerventional stroke treatment without exposing patients to procedural risks. As the global demand for thrombectomy rises, training strategies that ensure procedural competence while addressing workforce constraints are increasingly important. With this pilot study, we aim to generate a hypothesis as to whether additional exposure of trainees to mechanical thrombectomy could benefit from simulator training on top of the standard training carried out on flow models. This study was designed as an exploratory pilot investigation and was not able to provide inferential or confirmatory statistical conclusions. Methods: Six novice participants (advanced clinical-year medical students with completed anatomical and preclinical training, but without previous exposure to catheter-based interventions) performed two neurointerventional tasks, vascular access and mechanical thrombectomy (MTE), on flow models. After a baseline assessment, three participants received standard model-based training (control group), and three received additional simulator training using a high-fidelity angiography simulator (Mentice VIST G5). Performance was reassessed after four weeks using technical and clinical surrogate metrics, which were ranked and descriptively analyzed. Results: No relevant differences were observed between groups for the vascular access task. In contrast, the simulator group demonstrated a trend toward improved performance in the MTE task, with greater gains in efficiency, autonomy, and procedural safety. Conclusions: Our findings indicate a possible benefit of even brief simulator exposure for skill acquisition for complex endovascular procedures such as MTE. While conventional training may suffice for basic skills, simulation may be particularly helpful in supporting learning in more advanced tasks.

The objective of this study was to analyze immune-related adverse events (irAEs) in a real-world data sample and examine the differences in incidence between affected organ systems, irAE severity, therapeutic agent, and gender. We retrospectively analyzed all consecutive patients treated with anti-cytotoxic T-lymphocyte associated protein 4 (CTLA-4) antibodies, anti-programmed death 1 (PD-1) inhibitors, and programmed death-ligand 1 (PD-L1) inhibitors between January 2020 and May 2023 in a tertiary referral center in Switzerland. IrAEs documented in the electronic health records (EHR) were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) and analyzed descriptively. Among the 500 patients, 196 (39.2%) were female. Treatments included pembrolizumab (51.2%), atezolizumab (20.2%), nivolumab (14.4%), durvalumab (6.4%), ipilimumab in combination with nivolumab (4.8%), cemiplimab (1.4%), avelumab (1.2%), and ipilimumab (0.4%). N = 216 (43.2%) patients had ≥ 1 irAEs (females: 47.4%; males: 40.5%). Severe (≥ grade 3) irAEs were reported in 13.6% of patients. The following irAE incidences were found: dermatological (15.2%), gastrointestinal (13.0%), endocrine (10.8%), musculoskeletal (4.8%), pulmonary (3.8%), systemic (3.6%), neurological (2.6%), cardiac (1.4%), renal (1.4%), hematological (0.6%), and ocular (0.2%). Nearly half of the patients experienced ≥ 1 irAEs, of which one-third severe. Females experienced more irAEs than males, above all due to a higher incidence of grade 1 irAEs. Only about half of the irAEs were reported as coded diagnosis. Further prospective studies on irAEs are warranted using structured documentation. The online version contains supplementary material available at 10.1186/s12885-025-14733-5.

Objectives: Despite frequent diagnosis of anemia of inflammation in hospitalized patients, little is known about patients' sex‐specific differences in iron deficiency (ID) and its biomarkers. We aimed to study sex‐specific differences in anemic patients with inflammation and their influence on iron biomarkers. Methods: This retrospective cross‐sectional study included anemic patients with inflammation (CRP > 5 mg/L) hospitalized at a Swiss tertiary referral center (01.01.2020–31.12.2023). ID was defined as ferritin‐index (sTfR/log(ferritin)) ≥ 1.5. Patient characteristics were reported as medians for continuous variables and frequencies for categorical variables. Age, laboratory parameters, treatment, comorbidities, illness severity, and in‐hospital mortality were analyzed. Sex‐specific effects on ID biomarkers (ferritin‐index, sTfR) were assessed using linear regression models. Results: Of 439 participants, 41.2% were female. 44.2% had ID (women: 49.7%, men: 40.3%, p = 0.052). Regression models showed no association between log(ferritin‐index) and sex (coefficient 0.02, 95% CI −0.13 to 0.18, p = 0.76). Ferritin levels were lower in women (221.0 vs. 373 μg/L, p = 0.014). No sex differences in in‐hospital mortality were observed (women 7.2%, men 4.3%, p = 0.21). Conclusions: Despite no significant sex differences regarding ID biomarkers, treatment, illness severity, and mortality, we hypothesize that factors beyond sex, for example underlying diseases and inflammation itself, play a more prominent role in these patients' outcomes.

Objective: To evaluate the detection rate and performance of 18F-FDG PET alone (PET), the combination of PET and low-dose thick-slice CT (PET/lCT), PET and diagnostic thin-slice CT (PET/dCT), and additional computer-aided detection (PET/dCT/CAD) for lung nodules (LN)/metastases in tumor patients. Along with this, assessment of inter-reader agreement and time requirement for different techniques were evaluated as well. Methods: In 100 tumor patients (56 male, 44 female; age range: 22–93 years, mean age: 60 years) 18F-FDG PET images, low-dose CT with shallow breathing (5 mm slice thickness), and diagnostic thin-slice CT (1 mm slice thickness) in full inspiration were retrospectively evaluated by three readers with variable experience (junior, mid-level, and senior) for the presence of lung nodules/metastases and additionally analyzed with CAD. Time taken for each analysis and number of the nodules detected were assessed. Sensitivity, specificity, positive and negative predictive value, accuracy, and Receiver operating characteristic (ROC) analysis of each technique was calculated. Histopathology and/or imaging follow-up served as reference standard for the diagnosis of metastases. Results: Three readers, on an average, detected 40 LN in 17 patients with PET only, 121 LN in 37 patients using ICT, 283 LN in 60 patients with dCT, and 282 LN in 53 patients with CAD. On average, CAD detected 49 extra LN, missed by the three readers without CAD, whereas CAD overall missed 53 LN. There was very good inter-reader agreement regarding the diagnosis of metastases for all four techniques (kappa: 0.84–0.93). The average time required for the evaluation of LN in PET, lCT, dCT, and CAD was 25, 31, 60, and 40 s, respectively; the assistance of CAD lead to average 33% reduction in time requirement for evaluation of lung nodules compared to dCT. The time-saving effect was highest in the less experienced reader. Regarding the diagnosis of metastases, sensitivity and specificity combined of all readers were 47.8%/96.2% for PET, 80.0%/81.9% for PET/lCT, 100%/56.7% for PET/dCT, and 95.6%/64.3% for PET/CAD. No significant difference was observed regarding the ROC AUC (area under the curve) between the imaging methods. Conclusion: Implementation of CAD for the detection of lung nodules/metastases in routine 18F-FDG PET/CT read-out is feasible. The combination of diagnostic thin-slice CT and CAD significantly increases the detection rate of lung nodules in tumor patients compared to the standard PET/CT read-out. PET combined with low-dose CT showed the best balance between sensitivity and specificity regarding the diagnosis of metastases per patient. CAD reduces the time required for lung nodule/metastasis detection, especially for less experienced readers.

Objective To evaluate the value of SPECT/CT (single photon emission computed tomography/computed tomography) in foot and ankle arthrodesis and development of secondary osteoarthritis in the adjacent joints. Materials and methods SPECT/CT of 140 joints in the foot and ankle (34 upper ankle (UA), 28 lower ankle (LA), 27 talonavicular (TN), 12 calcaneo-cuboidal (CC), and 39 other smaller joints after arthrodesis in 72 patients were evaluated retrospectively regarding fusion grade in CT (0 = no fusion, 1 = < 50% fusion, 2 = > 50% fusion, 3 = complete fusion) and radiotracer uptake (0 = no uptake, 1 = mild uptake, 2 = moderate uptake, 3 = high uptake) on SPECT/CT. Severity of osteoarthritis (1 = mild, 2 = moderate, 3 = severe) and radiotracer uptake grade in adjacent joints was also assessed. In 54 patients, clinical information about interventions in the follow-up was available. Results According to the SPECT/CT, arthrodesis was successful (grade 2 or 3 CT fusion and grade 0 or 1 uptake) in 73% (25/34) of UA joints, 71% (20/28) of LA joints, 67% (18/27) TN, 100% (12/12) CC joints, and 62% (24/39) of other smaller joints. In 12 joints, there were discrepant findings in SPECT/CT (fusion grade 2 and uptake grade 2 or 3 (n = 9); or, fusion grade 0 or 1 and uptake grade 1 (n = 3)). The fusion rate 6–12 months after arthrodesis was 42% (14/33), 59% (20/34) after 13–24 months, and 89% (65/73) after more than 24 months, respectively. Average radiotracer uptake in arthrodesis decreased with age: 6–12 months: 1.60, 12–24 months: 1.32, > 24 months: 0.38. There was a significant negative correlation between radiotracer uptake grade and CT fusion grade. Osteoarthritis was observed in 131 adjacent joints. During the post scan follow-up, additional arthrodeses were performed in 33 joints, of which 11 joints were re-arthrodesis and 22 were new arthrodeses in osteoarthritic adjacent joints. All these 11 joints with failed arthrodesis had grade 0 of CT fusion and grade 2 or 3 of radiotracer uptake. All 22 adjacent joints with osteoarthritis, which subsequently underwent arthrodesis, had grade 2 or 3 radiotracer uptake, and the primary arthrodesis joints were healed and fused in all these cases. Conclusion Bone SPECT/CT is a valuable hybrid imaging tool in the evaluation of foot and ankle arthrodesis and gives additional useful information about the development of secondary osteoarthritis in the adjacent joints with higher value for the assessment of secondary osteoarthritis. A practical four-type classification (‘Lucerne Criteria’) combining metabolic and morphologic SPECT/CT information for evaluation of arthrodesis joints has been proposed.

Study design A cross-sectional study. Objective This study aimed to investigate the vitamin D status after acute spinal cord injury (SCI) onset. Setting Specialized SCI rehabilitation center in Switzerland. Methods Patients admitted to the center after an acute SCI onset were included. The prevalence of a deficient (25(OH)D ≤ 50 nmol/l), insufficient (50 < 25(OH)D ≤ 75 nmol/l) and sufficient (25(OH)D > 75 nmol/l) vitamin D status were determined after admission. Vitamin D status was compared between different patient groups based on demographic and SCI characteristics. The occurrence of bed rest, falls and pressure injuries were also assessed. Results In total, 87 patients (median (interquartile range); 53 (39–67) years, 25 females, 66 traumatic SCI, 54 paraplegia) were included. Assessed a median of 15 (9–22) days after SCI onset, median vitamin D status was 41 (26–57) (range 8–155) nmol/l. The majority of patients had a deficient (67%, 95% confidence interval (95% CI) 0.56–0.76) or insufficient (25%, 95% CI 0.17–0.36) vitamin D status. A moderate negative correlation was found between vitamin D status and body mass index (p = 0.003). A moderate positive correlation was found between vitamin D and calcium status (p = 0.01). Conclusion A deficient or insufficient vitamin D status directly after SCI onset is highly prevalent. Vitamin D status should be carefully observed during acute SCI rehabilitation. We recommend that all patients with recent SCI onset should receive vitamin D supplementation with a dosage depending on their actual vitamin D status.

Diffusion kurtosis imaging (DKI) is applied to gain insights into the microstructural organization of brain tissues. However, the reproducibility of DKI outside brain white matter, particularly in combination with advanced estimation to remedy its noise sensitivity, remains poorly characterized. Therefore, in this study, we investigated the variability and reliability of DKI metrics while correcting implausible values with a fit method called mean kurtosis (MK)‐Curve. A total of 10 volunteers (four women; age: 41.4 ± 9.6 years) were included and underwent two MRI examinations of the brain. The images were acquired on a clinical 3‐T scanner and included a T1‐weighted image and a diffusion sequence with multiple diffusion weightings suitable for DKI. Region of interest analysis of common kurtosis and tensor metrics derived with the MK‐Curve DKI fit was performed, including intraclass correlation (ICC) and Bland–Altman (BA) plot statistics. A p value of less than 0.05 was considered statistically significant. The analyses showed good to excellent agreement of both kurtosis tensor‐ and diffusion tensor‐derived MK‐Curve–corrected metrics (ICC values: 0.77–0.98 and 0.87–0.98, respectively), with the exception of two DKI‐derived metrics (axial kurtosis in the cortex: ICC = 0.68, and radial kurtosis in deep gray matter: ICC = 0.544). Non‐MK‐Curve–corrected kurtosis tensor‐derived metrics ranged from 0.01 to 0.52 and diffusion tensor‐derived metrics from 0.06 to 0.66, indicating poor to moderate reliability. No structural bias was observed in the BA plots for any of the diffusion metrics. In conclusion, MK‐Curve–corrected DKI metrics of the human brain can be reliably acquired in white and gray matter at 3 T and DKI metrics have good to excellent agreement in a test–retest setting.