Institut für diagnostische und interventionelle Radiologie (Institut für Röntgendiagnostik)
Refine
Has Fulltext
- yes (25)
Is part of the Bibliography
- yes (25)
Year of publication
- 2023 (25) (remove)
Document Type
- Journal article (19)
- Doctoral Thesis (6)
Keywords
- magnetic resonance imaging (3)
- CT angiography (2)
- cartilage (2)
- computed tomography (2)
- translational research (2)
- AMADEUS (1)
- Bildgebendes Verfahren (1)
- Echtzeit (1)
- Gallengangsstenose (1)
- Gefäßverschluss (1)
- Hand (1)
- Herzfunktion (1)
- Herzmuskel (1)
- Hyperämie (1)
- Interventionsradiologie (1)
- Intravenöse Applikation (1)
- KOOS (1)
- Karpus (1)
- Kernspintomografie (1)
- Kernspintomographie (1)
- Kontrastmittel (1)
- Lungenembolie (1)
- MRT (1)
- Onkologie (1)
- PEFB (1)
- PROM (1)
- SL-Band (1)
- Stent (1)
- TFCC (1)
- Trauma (1)
- Triangulärer fibrokartilaginärer Komplex (1)
- Vascular closure devices (1)
- Vena cava inferior (1)
- X-ray computed (1)
- Zangenbiopsie (1)
- access site complications (1)
- ankle (1)
- antegrade puncture (1)
- aorta (1)
- arthrography (1)
- biliäre Stenose (1)
- biliäre Striktur (1)
- biomedical engineering (1)
- bone (1)
- bone remineralization (1)
- bone replacement material (1)
- breast cancer imaging (1)
- cancellous bone (1)
- cancer imaging (1)
- carcinoma (1)
- cardiovascular MRI (1)
- chiasma antebrachii (1)
- chondral defect (1)
- cine loop (1)
- computational neural networks (1)
- computed tomography angiography (CTA) (1)
- continuous extracorporeal femoral perfusion model (1)
- conventional imaging (1)
- convolution kernel (1)
- correlation (1)
- cross-sectional imaging (1)
- digital subtraction angiography (DSA) (1)
- drillability (1)
- dual-energy CT (1)
- dual-source CT (1)
- electrical and electronic engineering (1)
- endovaskuläre Therapie (1)
- experimental models of disease (1)
- femoral access (1)
- femoral arteries (1)
- flexor digitorum superficialis (1)
- flexor tendon (1)
- fluoroscopy (1)
- fracture (1)
- gadoliniumhaltiges Kontrastmittel (1)
- giant cell arteritis (1)
- heart (1)
- high tibial osteotomy (1)
- imaging (1)
- intravascular ultrasound (IVUS) (1)
- intravenös (1)
- knee (1)
- large animal models (1)
- late enhancement (1)
- late gadolinium-enhancement (1)
- lymphatic metastasis (1)
- machine learning (1)
- magnesium phosphate cement (1)
- maligne untere Einflussstauung (1)
- multiple myeloma (1)
- musculoskeletal system (1)
- neoadjuvant therapies (1)
- neuronavigation (1)
- non-small-cell lung (1)
- novel human cadaveric perfusion model (1)
- obesity (1)
- ophthalmic artery (1)
- optic nerve (1)
- orbit (1)
- organoid (1)
- osteoarthritis (1)
- pedicle screws (1)
- perfusion map (1)
- photon-counting (1)
- photon-counting CT (1)
- photon-counting computed tomography (CT) (1)
- photon-counting-detector CT (1)
- phytic acid (1)
- pig (1)
- positive nodal status (1)
- post-neoadjuvant therapies (1)
- preclinical research (1)
- pulmonary embolism (1)
- radiation dosage (1)
- radiation dose (1)
- radiation dose reduction (1)
- radiology (1)
- radiomics (1)
- real-time imaging (1)
- reproducibility of results (1)
- research infrastructure (1)
- small pixel effect (1)
- small-cell lung (1)
- spectral CT (1)
- spectral imaging (1)
- spine (1)
- spiral trajectory (1)
- three-dimensional imaging (1)
- tomography (1)
- traumatisch (1)
- ultrahigh resolution (1)
- ultrahigh-field MRI (1)
- vertebral pedicles (1)
- virtual non-contrast (1)
- whole-body imaging (1)
Institute
- Institut für diagnostische und interventionelle Radiologie (Institut für Röntgendiagnostik) (25)
- Institut für Anatomie und Zellbiologie (8)
- Klinik und Poliklinik für Allgemein-, Viszeral-, Gefäß- und Kinderchirurgie (Chirurgische Klinik I) (3)
- Institut für diagnostische und interventionelle Neuroradiologie (ehem. Abteilung für Neuroradiologie) (2)
- Klinik und Poliklinik für Unfall-, Hand-, Plastische und Wiederherstellungschirurgie (Chirurgische Klinik II) (2)
- Lehrstuhl für Orthopädie (2)
- Medizinische Klinik und Poliklinik II (2)
- Abteilung für Funktionswerkstoffe der Medizin und der Zahnheilkunde (1)
- Augenklinik und Poliklinik (1)
- Deutsches Zentrum für Herzinsuffizienz (DZHI) (1)
Objectives
We developed a novel human cadaveric perfusion model with continuous extracorporeal femoral perfusion suitable for performing intra-individual comparison studies, training of interventional procedures and preclinical testing of endovascular devices. Objective of this study was to introduce the techniques and evaluate the feasibility for realistic computed tomography angiography (CTA), digital subtraction angiography (DSA) including vascular interventions, and intravascular ultrasound (IVUS).
Methods
The establishment of the extracorporeal perfusion was attempted using one formalin-fixed and five fresh-frozen human cadavers. In all specimens, the common femoral and popliteal arteries were prepared, introducer sheaths inserted, and perfusion established by a peristaltic pump. Subsequently, we performed CTA and bilateral DSA in five cadavers and IVUS on both legs of four donors. Examination time without unintentional interruption was measured both with and without non-contrast planning CT. Percutaneous transluminal angioplasty and stenting was performed by two interventional radiologists on nine extremities (five donors) using a broad spectrum of different intravascular devices.
Results
The perfusion of the upper leg arteries was successfully established in all fresh-frozen but not in the formalin-fixed cadaver. The experimental setup generated a stable circulation in each procedure (ten upper legs) for a period of more than six hours. Images acquired with CT, DSA and IVUS offered a realistic impression and enabled the sufficient visualization of all examined vessel segments. Arterial cannulating, percutaneous transluminal angioplasty as well as stent deployment were feasible in a way that is comparable to a vascular intervention in vivo. The perfusion model allowed for introduction and testing of previously not used devices.
Conclusions
The continuous femoral perfusion model can be established with moderate effort, works stable, and is utilizable for medical imaging of the peripheral arterial system using CTA, DSA and IVUS. Therefore, it appears suitable for research studies, developing skills in interventional procedures and testing of new or unfamiliar vascular devices.
Multiple myeloma (MM) frequently induces persisting osteolytic manifestations despite hematologic treatment response. This study aimed to establish a biometrically valid study endpoint for bone remineralization through quantitative and qualitative analyses in sequential CT scans. Twenty patients (seven women, 58 ± 8 years) with newly diagnosed MM received standardized induction therapy comprising the anti-SLAMF7 antibody elotuzumab, carfilzomib, lenalidomide, and dexamethasone (E-KRd). All patients underwent whole-body low-dose CT scans before and after six cycles of E-KRd. Two radiologists independently recorded osteolytic lesion sizes, as well as the presence of cortical destruction, pathologic fractures, rim and trabecular sclerosis. Bland–Altman analyses and Krippendorff’s α were employed to assess inter-reader reliability, which was high for lesion size measurement (standard error 1.2 mm) and all qualitative criteria assessed (α ≥ 0.74). After six cycles of E-KRd induction, osteolytic lesion size decreased by 22% (p < 0.001). While lesion size response did not correlate with the initial lesion size at baseline imaging (Pearson’s r = 0.144), logistic regression analysis revealed that the majority of responding osteolyses exhibited trabecular sclerosis (p < 0.001). The sum of osteolytic lesion sizes on sequential CT scans defines a reliable study endpoint to characterize bone remineralization. Patient level response is strongly associated with the presence of trabecular sclerosis.
Ultra-high-resolution photon-counting detector CT arthrography of the ankle: a feasibility study
(2023)
This study was designed to investigate the image quality of ultra-high-resolution ankle arthrography employing a photon-counting detector CT. Bilateral arthrograms were acquired in four cadaveric specimens with full-dose (10 mGy) and low-dose (3 mGy) scan protocols. Three convolution kernels with different spatial frequencies were utilized for image reconstruction (ρ\(_{50}\); Br98: 39.0, Br84: 22.6, Br76: 16.5 lp/cm). Seven radiologists subjectively assessed the image quality regarding the depiction of bone, hyaline cartilage, and ligaments. An additional quantitative assessment comprised the measurement of noise and the computation of contrast-to-noise ratios (CNR). While an optimal depiction of bone tissue was achieved with the ultra-sharp Br98 kernel (S ≤ 0.043), the visualization of cartilage improved with lower modulation transfer functions at each dose level (p ≤ 0.014). The interrater reliability ranged from good to excellent for all assessed tissues (intraclass correlation coefficient ≥ 0.805). The noise levels in subcutaneous fat decreased with reduced spatial frequency (p < 0.001). Notably, the low-dose Br76 matched the CNR of the full-dose Br84 (p 0.999) and superseded Br98 (p < 0.001) in all tissues. Based on the reported results, a photon-counting detector CT arthrography of the ankle with an ultra-high-resolution collimation offers stellar image quality and tissue assessability, improving the evaluation of miniscule anatomical structures. While bone depiction was superior in combination with an ultra-sharp convolution kernel, soft tissue evaluation benefited from employing a lower spatial frequency.
Recent dissection studies resulted in the introduction of the term “chiasma antebrachii”, which represents an intersection of the flexor digitorum superficialis (FDS) tendons for digits 2 and 3 in the distal third of the forearm. This retrospective investigation aimed to provide an MRI-based morphologic analysis of the chiasma antebrachii. In 89 patients (41 women, 39.3 ± 21.3 years), MRI examinations of the forearm (2010–2021) were reviewed by two radiologists, who evaluated all studies for the presence and length of the chiasma as well as its distance from the distal radioulnar and elbow joint. The chiasma antebrachii was identified in the distal third of the forearm in 88 patients (98.9%), while one intersection was located more proximally in the middle part. The chiasma had a median length of 28 mm (interquartile range: 24–35 mm). Its distances to the distal radioulnar and elbow joint were 16 mm (8–25 mm) and 215 mm (187–227 mm), respectively. T1-weighted post-contrast sequences were found to be superior to T2- or proton-density-weighted sequences in 71 cases (79.8%). To conclude, the chiasma antebrachii is part of the standard FDS anatomy. Knowledge of its morphology is important, e.g., in targeted injections of therapeutics or reconstructive surgery.
The use of bone-cement-enforced osteosynthesis is a growing topic in trauma surgery. In this context, drillability is a desirable feature for cements that can improve fracture stability, which most of the available cement systems lack. Therefore, in this study, we evaluated a resorbable and drillable magnesium-phosphate (MgP)-based cement paste considering degradation behavior and biocompatibility in vivo. Two different magnesium-phosphate-based cement (MPC) pastes with different amounts of phytic acid (IP 6) as setting retarder (MPC 22.5 and MPC 25) were implanted in an orthotopic defect model of the lateral femoral condyle of New Zealand white rabbits for 6 weeks. After explantation, their resorption behavior and material characteristics were evaluated by means of X-ray diffraction (XRD), porosimetry measurement, histological staining, peripheral quantitative computed tomography (pQCT), cone-beam computed tomography (CBCT) and biomechanical load-to-failure tests. Both cement pastes displayed comparable results in mechanical strength and resorption kinetics. Bone-contact biocompatibility was excellent without any signs of inflammation. Initial resorption and bone remodeling could be observed. MPC pastes with IP 6 as setting retardant have the potential to be a valuable alternative in distinct fracture patterns. Drillability, promising resorption potential and high mechanical strength confirm their suitability for use in clinical routine.