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"Sohns, Jan M."
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From the Bottlecap to the Bottleneck: Frequent Esophageal Impaction of Bottlecaps Among Young Males in a Small University Town
2022
There have been few reports of ingestion of bottlecaps worldwide. However, all of these seemed to be unlikely accidental ingestions with a comic side effect. In contrast to this, the authors of this study found an accumulation of bottlecap ingestions in a small university town. Hence, we conducted a study to investigate the nature of these ingestions. We conducted a retrospective cohort study in a tertiary referral center in a small German university town (Göttingen). All patients that were admitted for esophageal foreign bodies were screened for accidental ingestion of bottlecaps and included in the study at hand. Overall, there were 14 cases of bottlecap ingestion within 12 years. Patients were exclusively male, average age was 23.0 ± 4.2 years, ranging from 18.3 to 35.6 years. In 13 out of 14 cases, association to a fraternity was found. Young men, particularly those belonging to a fraternity, should be beware of bottlecap ingestion when consuming beer in risky rituals in small university towns. Alternatively, competitive beer drinking may generally be avoided.
Journal Article
Quantification of Left Ventricular Torsion and Diastolic Recoil Using Cardiovascular Magnetic Resonance Myocardial Feature Tracking
by
Hasenfuß, Gerd
,
Unterberg-Buchwald, Christina
,
Hussain, Shazia T.
in
Adult
,
Algorithms
,
Biology and Life Sciences
2014
Cardiovascular magnetic resonance feature tracking (CMR-FT) offers quantification of myocardial deformation from routine cine images. However, data using CMR-FT to quantify left ventricular (LV) torsion and diastolic recoil are not yet available. We therefore sought to evaluate the feasibility and reproducibility of CMR-FT to quantify LV torsion and peak recoil rate using an optimal anatomical approach.
Short-axis cine stacks were acquired at rest and during dobutamine stimulation (10 and 20 µg · kg(-1) · min(-1)) in 10 healthy volunteers. Rotational displacement was analysed for all slices. A complete 3D-LV rotational model was developed using linear interpolation between adjacent slices. Torsion was defined as the difference between apical and basal rotation, divided by slice distance. Depending on the distance between the most apical (defined as 0% LV distance) and basal (defined as 100% LV distance) slices, four different models for the calculation of torsion were examined: Model-1 (25-75%), Model-2 (0-100%), Model-3 (25-100%) and Model-4 (0-75%). Analysis included subendocardial, subepicardial and global torsion and recoil rate (mean of subendocardial and subepicardial values).
Quantification of torsion and recoil rate was feasible in all subjects. There was no significant difference between the different models at rest. However, only Model-1 (25-75%) discriminated between rest and stress (Global Torsion: 2.7 ± 1.5° cm(-1), 3.6 ± 2.0° cm(-1), 5.1 ± 2.2° cm(-1), p<0.01; Global Recoil Rate: -30.1 ± 11.1° cm(-1) s(-1),-46.9 ± 15.0° cm(-1) s(-1),-68.9 ± 32.3° cm(-1) s(-1), p<0.01; for rest, 10 and 20 µg · kg(-)1 · min(-1) of dobutamine, respectively). Reproducibility was sufficient for all parameters as determined by Bland-Altman analysis, intraclass correlation coefficients and coefficient of variation.
CMR-FT based derivation of myocardial torsion and recoil rate is feasible and reproducible at rest and with dobutamine stress. Using an optimal anatomical approach measuring rotation at 25% and 75% apical and basal LV locations allows effective quantification of torsion and recoil dynamics. Application of these new measures of deformation by CMR-FT should next be explored in disease states.
Journal Article
Parameters for estimating the feasibility of implantation of a semi-implantable bone conduction device (SIBCD) in children and adolescents
2023
Purpose
In children and adolescents, preoperative planning for a semi-implantable bone conduction device (SIBCD) is crucial. The geometric changes of the new version of a common SIBCD should enable a higher rate of successful implantation due to its flatter actuator. Thus, this radioanatomic study compared the rate of successful implantation of both device versions at the traditional mastoidal localization and two alternative sites, retrosigmoidal, and parietal, and investigated parameters helping to estimate the feasibility.
Methods
A retrospective analysis of 136 CT scans of 0 to 20-year-old patients, evaluation of demographic parameters, radioanatomy, and assessment of head diameter was conducted. The feasibility was investigated for certain age groups at three implantation sites. Prediction of feasible implantation by means of different parameters was calculated.
Results
A significant higher implantation rate was observed with the new device for all three sites and age groups. The age group of 6–8 years (
n
= 19) had most striking differences with a 58.1% rate of successful implantation with the new device without spacer (80% with spacer) at the mastoidal localization, whereas none with the old implant. Head diameter was identified as the most predictive parameter regarding all implantation sites (mastoidal:
p
= 0.030; retrosigmoidal:
p
= 0.006; parietal:
p
< 0.0001), age for the mastoidal (
p
< 0.0001) and retrosigmoidal (
p
< 0.0001), and gender for the parietal site (
p
= 0.001).
Conclusion
The geometric changes of the actuator lead to a higher rate of successful implantation in all age-groups and all three localizations with reducing the requirement for spacers. Parameters age and head diameter might aid in estimating the rate of successful implantation in young patients and may be a novel tool to assist in the decision-making process for a SIBCD.
Journal Article
Comparison of standard and delayed imaging to improve the detection rate of 68GaPSMA I&T PET/CT in patients with biochemical recurrence or prostate-specific antigen persistence after primary therapy for prostate cancer
by
Nordlohne, Stefan
,
Schmuck, Sebastian
,
Henkenberens, Christoph
in
Aged
,
Aged, 80 and over
,
Antigens
2017
Purpose
The aim of this study was to assess the value of dual-time point imaging in PET/CT for detection of biochemically recurrent or persistent prostate cancer, using the prostate-specific membrane antigen (PSMA) ligand [
68
Ga]PSMA I&T.
Methods
240 patients who underwent a [
68
Ga]PSMA I&T PET/CT in the context of biochemical relapse of prostate cancer were included in this retrospective analysis. Imaging consisted of a standard whole-body PET/CT (1 h p.i.), followed by delayed (3 h p.i.) imaging of the abdomen. PSA-stratified proportions of positive PET/CT results, standardized uptake values and target-to-background ratios were analyzed, and compared between standard and delayed imaging.
Results
The overall detection rates of [
68
Ga]PSMA I&T PET/CT were 94.2, 71.8, 58.6, 55.9 and 38.9% for PSA levels of ≥2, 1 to <2, 0.5 to <1, >0.2 to <0.5, and 0.01 to 0.2 ng/mL, respectively. Although the target-to-background ratio improved significantly over time (
P
< 0.0001), the majority (96.6%) of all lesions suggestive of recurrent disease could already be detected in standard imaging. Delayed imaging at 3 h p.i. exclusively identified pathologic findings in 5.4% (10/184) of abnormal [
68
Ga]PSMA I&T PET/CT scans, and exclusively detected 3.4% (38/1134) of all lesions suggestive of recurrent disease.
Conclusions
[
68
Ga]PSMA I&T PET/CT shows high detection rates in patients with prostate-specific antigen persistence or biochemical recurrence of prostate cancer. Delayed imaging can detect lesions with improved contrast compared to standard imaging. However, the impact on detection rates was limited in this study.
Journal Article
Real-time cardiovascular magnetic resonance at 1.5 T using balanced SSFP and 40 ms resolution
by
Voit, Dirk
,
Zhang, Shuo
,
Unterberg-Buchwald, Christina
in
Abnormal wall motion
,
Acquisitions
,
Adolescent
2013
While cardiovascular magnetic resonance (CMR) commonly employs ECG-synchronized cine acquisitions with balanced steady-state free precession (SSFP) contrast at 1.5 T, recent developments at 3 T demonstrate significant potential for T1-weighted real-time imaging at high spatiotemporal resolution using undersampled radial FLASH. The purpose of this work was to combine both ideas and to evaluate a corresponding real-time CMR method at 1.5 T with SSFP contrast.
Radial gradient-echo sequences with fully balanced gradients and at least 15-fold undersampling were implemented on two CMR systems with different gradient performance. Image reconstruction by regularized nonlinear inversion (NLINV) was performed offline and resulted in real-time SSFP CMR images at a nominal resolution of 1.8 mm and with acquisition times of 40 ms.
Studies of healthy subjects demonstrated technical feasibility in terms of robustness and general image quality. Clinical applicability with access to quantitative evaluations (e.g., ejection fraction) was confirmed by preliminary applications to 27 patients with typical indications for CMR including arrhythmias and abnormal wall motion. Real-time image quality was slightly lower than for cine SSFP recordings, but considered diagnostic in all cases.
Extending conventional cine approaches, real-time radial SSFP CMR with NLINV reconstruction provides access to individual cardiac cycles and allows for studies of patients with irregular heartbeat.
Journal Article
Absence of DNA double-strand breaks in human peripheral blood mononuclear cells after 3 Tesla magnetic resonance imaging assessed by γH2AX flow cytometry
by
Unterberg-Buchwald, Christina
,
Schuster, Andreas
,
Fasshauer, Martin
in
Chromosomes
,
Cytometry
,
Deoxyribonucleic acid
2018
ObjectivesMagnetic resonance imaging (MRI) is regarded as a non-harming and non-invasive imaging modality with high tissue contrast and almost no side effects. Compared to other cross-sectional imaging modalities, MRI does not use ionising radiation. Recently, however, strong magnetic fields as applied in clinical MRI scanners have been suspected to induce DNA double-strand breaks in human lymphocytes.MethodsIn this study we investigated the impact of 3-T cardiac MRI examinations on the induction of DNA double-strand breaks in peripheral mononuclear cells by γH2AX staining and flow cytometry analysis. The study cohort consisted of 73 healthy non-smoking volunteers with 36 volunteers undergoing CMRI and 37 controls without intervention. Differences between the two cohorts were analysed by a mixed linear model with repeated measures.ResultsBoth cohorts showed a significant increase in the γH2AX signal from baseline to post-procedure of 6.7 % (SD 7.18 %) and 7.8 % (SD 6.61 %), respectively. However, the difference between the two groups was not significant.ConclusionBased on our study, γH2AX flow cytometry shows no evidence that 3-T MRI examinations as used in cardiac scans impair DNA integrity in peripheral mononuclear cells.Key Points• No evidence for DNA double-strand breaks after cardiac MRI.• Prospective study underlines safe use of MRI with regard to DNA damage.• Controlled trial involving both genders investigating DNA DSBs after 3-T MRI.
Journal Article
Incidental findings in cardiac magnetic resonance imaging: superiority of bSSFP over T1w-HASTE for extra-cardiac findings assessment
2017
Incidental findings are frequent in radiological examinations and may have an impact on further patient management. The aim of this retrospective study was to analyze, which of two thoracic scout sequences is more suitable for detecting incidental extra-cardiac findings at cardiac magnetic resonance imaging (CMRI) with stress perfusion. During a 14-month period clinically indicated stress perfusion CMRI was performed in 97 consecutive patients. For anatomical orientation ECG-triggered (electrocardiography) T1w-Half-fourier acquisition single-shot turbo spin-echo (HASTE) and balanced steady state free precession (bSSFP) sequences were performed for planning the standard cardiac sequences. Two radiologists independently studied incidental extra-cardiac findings with both sequences and rated the diagnostic confidence of the sequences for this assessment using a multinomial model. Furthermore, the interobserver agreement between the observers was assessed by weighted kappa statistics. Eight patients without incidental findings were excluded. In the other 89 patients a total of 153 incidental extra-cardiac findings were observed. Overall, 47.1% of findings were seen with better diagnostic confidence at bSSFP as opposed to 20.6% at T1w-HASTE. 32.4% of findings were equally well seen with both sequences. Consequently the bSSFP sequence was significantly better in terms of diagnostic confidence for detecting the majority of extra-cardiac incidental findings (P < 0.01), whereas a minority of findings was better visible by the HASTE sequence. The weighted kappa statistics was 0.85, indicating good interobserver agreement. Compared with T1w-HASTE, the bSSFP sequence improved the visibility of incidental extra-cardiac findings at stress perfusion CMRI. While all findings were seen on both sequences, bSSFP resulted in improved diagnostic confidence, and the T1w-HASTE sequence provided complementary diagnostic information in only a minority of patients.
Journal Article
Persistent left superior vena cava detected after central venous catheter insertion
by
Unterberg-Buchwald, Christina
,
Fasshauer, Martin
,
Staab, Wieland
in
Case Study
,
Chronic obstructive pulmonary disease
,
Humanities and Social Sciences
2014
Introduction
Persistent left superior vena cava is a rare case with an appearance of 0.3% to 0.5% of individuals in general population. Indication for jugular venous intervention could be different, such as implantable venous catheters for oncological therapy. The present report describes a case of a patient with a persistent left superior vena cava detected after central venous catheter (CVC) installation using computer-assisted tomography (CT).
Case description
In a control chest X-ray the CVC was not in the right superior vena cava as expected to be. A following blood gas analysis revealed venous concentration. The consultation of additional CT diagnostics yielded a persistent left superior vena cava with an outlet to dilated coronary sinus.
Discussion and evaluation
The patient was followed over 1 year with the underlying disease of chronic obstructive pulmonary disease. Cardiac insufficiency, sinus aneurysm and arryhtmias could appear with growing age in patients with persistence left superior vena cava, but most of them are asymptomatic. Knowing the venous anatomy is important for correct position and function of e.g. totally implantable venous catheters, central lines or pacemakers.
Conclusion
The importance of early imaging diagnosis of this anatomical variation could optimize adequate therapy and finally improve living conditions. CT can help adapting correct therapy with correct diagnostics.
Journal Article