17 research outputs found

    DeepMB: Deep neural network for real-time optoacoustic image reconstruction with adjustable speed of sound

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    Multispectral optoacoustic tomography (MSOT) is a high-resolution functional imaging modality that can non-invasively access a broad range of pathophysiological phenomena by quantifying the contrast of endogenous chromophores in tissue. Real-time imaging is imperative to translate MSOT into clinical imaging, visualize dynamic pathophysiological changes associated with disease progression, and enable in situ diagnoses. Model-based reconstruction affords state-of-the-art optoacoustic images; however, the image quality provided by model-based reconstruction remains inaccessible during real-time imaging because the algorithm is iterative and computationally demanding. Deep learning affords faster reconstruction, but the lack of ground truth training data can lead to reduced image quality for in vivo data. We introduce a framework, termed DeepMB, that achieves accurate optoacoustic image reconstruction for arbitrary input data in 31 ms per image by expressing model-based reconstruction with a deep neural network. DeepMB facilitates accurate generalization to experimental test data through training on signals synthesized from real-world images and ground truth images generated by model-based reconstruction. The framework affords in-focus images for a broad range of anatomical locations because it supports dynamic adjustment of the reconstruction speed of sound during imaging. Furthermore, DeepMB is compatible with the data rates and image sizes of modern multispectral optoacoustic tomography scanners. We evaluate DeepMB on a diverse dataset of in vivo images and demonstrate that the framework reconstructs images 1000 times faster than the iterative model-based reference method while affording near-identical image qualities. Accurate and real-time image reconstructions with DeepMB can enable full access to the high-resolution and multispectral contrast of handheld optoacoustic tomography

    Grade II whiplash injuries to the neck: what is the benefit for patients treated by different physical therapy modalities?

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    <p>Abstract</p> <p>Background</p> <p>In a majority of cases, whiplash injuries are a domain of conservative therapy. Nevertheless it remains unclear whether physical therapy is of medical or economic benefit in patients with whiplash injuries.</p> <p>Methods</p> <p>Seventy patients with acute Quebec Task Force (QTF) grade II whiplash injuries were randomized to two therapy groups and received either active (APT) or passive (PPT) physical therapy. Patients were compared with regard to pain and range of motion with data obtained in an earlier study from a group with grade II whiplash injuries in which the therapy recommendation had been "act as usual" (AAU; n = 20). The above-mentioned parameters were assessed at 24 hours and two months after the injury. Furthermore patients' period of disability was documented after two months.</p> <p>Results</p> <p>After two months, patients in both the APT and PPT groups showed significant improvement in the median period of disability (active: 14 days; passive: 14 days) compared to the AAU group (49 days). No group difference was observed with regard to median improvement in range of motion (active: 120°; passive: 108°; activity as usual: 70°). The median pain reduction was significantly greater in the APT group (50.5) than in the PPT (39.2) or AAU group (28.8).</p> <p>Conclusion</p> <p>Our data show that active physical therapy results in enhanced pain reduction and shortening of post-injury disability. Therefore, active physical therapy should be considered the treatment of choice in patients with QTF grade II whiplash injuries.</p> <p>Trial registration</p> <p>The study complied with applicable German law and with the principles of the Helsinki Declaration and was approved by the institutional ethics commission.</p

    Deceleration during 'real life' motor vehicle collisions – a sensitive predictor for the risk of sustaining a cervical spine injury?

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    <p>Abstract</p> <p>Background</p> <p>The predictive value of trauma impact for the severity of whiplash injuries has mainly been investigated in sled- and crash-test studies. However, very little data exist for real-life accidents. Therefore, the predictive value of the trauma impact as assessed by the change in velocity of the car due to the collision (ΔV) for the resulting cervical spine injuries were investigated in 57 cases after real-life car accidents.</p> <p>Methods</p> <p>ΔV was determined for every car and clinical findings related to the cervical spine were assessed and classified according to the Quebec Task Force (QTF).</p> <p>Results</p> <p>In our study, 32 (56%) subjects did not complain about symptoms and were therefore classified as QTF grade 0; 25 (44%) patients complained of neck pain: 8 (14%) were classified as QTF grade I, 6 (10%) as QTF grade II, and 11 (19%) as QTF grade IV. Only a slight correlation (r = 0.55) was found between the reported pain and ΔV. No relevant correlation was found between ΔV and the neck disability index (r = 0.46) and between ΔV and the QTF grade (r = 0.45) for any of the collision types. There was no ΔV threshold associated with acceptable sensitivity and specificity for the prognosis of a cervical spine injury.</p> <p>Conclusion</p> <p>The results of this study indicate that ΔV is not a conclusive predictor for cervical spine injury in real-life motor vehicle accidents. This is of importance for surgeons involved in medicolegal expertise jobs as well as patients who suffer from whiplash-associated disorders (WADs) after motor vehicle accidents.</p> <p>Trial registration</p> <p>The study complied with applicable German law and with the principles of the Helsinki Declaration and was approved by the institutional ethics commission.</p

    Molekularbiologischer Nachweis von okkulten Tumorzellen beim Pankreaskopfkarzinom - AusmaĂź und prognostische Relevanz

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    Hintergrund: Die Fünf-Jahres-Überlebensrate beim Pankreaskarzinom liegt selbst nach kurativer Resektion bei höchstens 20 - 25 %. Frühzeitig treten Lokalrezidive und Organmetastasen auf. Es wird vermutet, dass bei diesen Patienten zum Zeitpunkt der Operation bereits eine lymphatische Ausbreitung von Tumorzellen erfolgt ist, die durch die routinemäßige histologische Untersuchung nicht erkannt wird. Methode: Bei 23 Patienten, bei denen wegen eines Pankreaskarzinoms eine pp-Whipple-Operation mit kurativer Zielsetzung durchgeführt wurde, wurde die histologische Untersuchung der regionalen Lymphknoten (LK) mit molekularbiologischen Nachweisverfahren verglichen. Molekularbiologisch wurden die LK auf das Vorliegen von K-ras-Mutationen und die Expression von Zytokeratin 20 untersucht. Ergebnisse: Im Primärtumor lagen bei 19 Patienten K-ras-Mutationen vor, die CK20-Expression erfolgte bei 12 Patienten. In den LK wurden bei 6 % histologisch, bei 18 % durch den Nachweis von K-ras-Mutationen, bei 19 % durch den Nachweis der CK20-Expression und bei 23 % durch die Kombination beider molekularbiologischer Verfahren Mikrometastasen nachgewiesen. Die Lokalisation der molekularbiologischen Mikrometastasen zeigt folgende Verteilung: 31 % interaortokavale LK, 16 % LK im Ligamentum hepatoduodenale, 4 % LK um den Truncus coeliacus und 0 % LK um die A. mesenterica superior. Ein Zusammenhang zum postoperativen Auftreten von Lokalrezidiven und Fernmetastasen wurde nicht festgestellt. Schlussfolgerung: Im Vergleich zur histologischen Untersuchung konnten durch beide molekularbiologische Nachweisverfahren mehr LK-Mikrometastasen entdeckt werden. Beide Verfahren tragen zu einer Verbesserung in der Beurteilung des LK-Status bei und führen zu einem genaueren Tumorstaging. Am häufigsten lagen Mikrometastasen in den interaortokavalen LK vor. Eine prognostische Bedeutung der molekularbiologisch nachgewiesenen Mikrometastasen für das Auftreten von Lokalrezidiven und Fernmetastasen konnte nicht gezeigt werden

    Training effects of combined resistance and proprioceptive neck muscle exercising

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    OBJECTIVES: To investigate training effects of two different resistance and proprioceptive exercising concepts of neck muscles. MATERIAL AND METHOD: Twenty-six healthy women participated in a randomized pilot trial. The test persons were randomized to two different neck-training programs (resistance training (RT) and proprioceptive resistance training (PRT)). They performed a standardized training program for the duration of ten weeks two times weekly. The neck strength, the cross-sectional area of three neck muscle groups (1. sternocleidomastoid muscles; 2. multifidus and semispinalis cervicis muscles; 3. semispinalis capitis and splenius muscles) and the proprioceptive capability evaluated by the dynamic joint repositioning error (DJRE) of the head were assessed pre- and post-intervention. RESULTS: Strength gain did not differ significantly between the two resistance training groups (PRT group: 8.2% to 29.3%; RT group: 1.4% to 19.8%). Change of hypertrophy of all neck muscle groups was significantly (p< 0.001 to p=0.013) greater in the PRT group (18.9% to 32.3%) than in the RT group (1.5% to 12.9%). The DJRE deteriorated with 35% in the RT group and did not change in PRT group (-2.0%). CONCLUSION: In combination with resistance training, proprioceptive training led to a significantly higher muscle hypertrophy and didn't effect a significant deterioration of the proprioceptive capability compared to isolated resistance training

    Short-term outcome of fragility fractures of the pelvis in the elderly treated with screw osteosynthesis and external fixator

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    Background!#!The treatment of fragility fractures of the pelvis is rising challenge for orthopedic trauma surgeons. Operative treatment should allow immediate full weight bearing and early mobilisation but should also be as minimal invasive as possible. Sacroiliac (SI) or transsacral transiliac screws (TSTI) alone or depending on the fracture in combination with an external fixator meets both of these criteria.!##!Material and methods!#!The outcome of 121 operatively treated patients with fragility fractures of the pelvis were evaluated in this retrospective study. Depending on the type of fracture the patients were treated with navigated SI screw or TSTI screw alone or in combination with an external fixator. All patients were operated in supine position in a hybrid-OR, which consists of a fixed robotic 3D flatpanel detector (Artis zeego, Siemens Healthineers, Germany) and a navigation system (BrainLab Curve, BrainLab, Germany).!##!Results!#!37 patients were treated with either one or two SI screws and 57 with one TSTI screw. An additional external fixator was combined with SI screws in 17 patients and with TSTI screws in 10 patients. The preoperative pain score was significantly higher compared to the postoperative score (5.1 ± 2.5 vs 2.2 ± 1.9, p &amp;lt; 0.05). Follow-up at 6 month was possible for 106 patients which showed screw loosening in 16.3% of the SI Screws (n = 49) compared to only 5.2% of TSTI screws (n = 57). No screw loosening was seen in the combination of TSTI-screw and external fixator (n = 10). There were two septic and three aseptic pin loosenings of the external fixator. Overall only one patient needed revision surgery due to screw loosening and local irritation. Overall 75.2% (n = 91) of the patients could be released in their home or in a rehabilitation unit and only 14% (n = 17) were released to a nursing home due to immobility despite the operation. Non-surgical complications rate was 21.5%.!##!Conclusion!#!SI or TSTI screws with possible combination with an external fixator show early pain relief and allows most of the patients to keep their former level of independence. With an also low surgical complication rate, it proved to be a safe and reliable treatment for fragility fractures of the pelvis. Due the effective pain relief and the minimal invasive approach, early mobilisation is possible and might prevent typical non-surgical complications which are very common during conservative treatment

    Reliability of a new virtual reality test to measure cervicocephalic kinaesthesia

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    The aim of this study was to investigate the cervicocephalic kinaesthesia of healthy subjects for gender and age effects and its reliability in a new virtual reality test procedure. 57 healthy subjects (30 male, 27 females; 18-64 years) were immersed into a virtual 3D scene via a headmounted display, which generated specific head movements. The joint repositioning error was determined in a static and dynamic test at the times T0, T1 (T0 + 10 minutes) and T2 (T0 + 24 hours). The intrasession reliability (T0-T1) and the intersession reliability (T0-T2) were analysed. In both tests no gender- or age-specific effects were found. In the overall group the means of the static test were 6.2 - 6.9 and of the dynamic test were 4.5 -4.9 . The intratest difference in the static test was -0.16 and the intertest difference was 0.47 . The intratest difference in the dynamic test was 0.42 and the intertest difference was 0.37 . The static and dynamic test was reproducible in healthy subjects, with minor deviations, irrespective of gender and age. The smaller interindividual differences in the dynamic test could be beneficial in the comparison of healthy individuals and individuals with cervical spine disorders

    Early Surgical Care of Anticoagulated Hip Fracture Patients Is Feasible—A Retrospective Chart Review of Hip Fracture Patients Treated with Hip Arthroplasty within 24 Hours

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    Anticoagulative medication such as antiplatelet drugs (PAI, acetylsalicylic acid and direct platelet aggregation inhibitors), vitamin-K-antagonist Warfarin (VKA) or direct oral anticoagulants (DOAC) are common among hip fracture patients, and the perioperative management of these patients is a rising challenge in orthopaedic trauma. Our objective was to determine the effect of oral anticoagulation in patients receiving early endoprosthetic treatment within 24 h after their admission. For the period from 2016 to 2020, a retrospective chart review of 221 patients (mean age 83 ± 7 years; 161 women and 60 men) who were treated either with hemi- (n = 209) or total hip arthroplasty (n = 12) within 24 h after their admission was performed. We identified 68 patients who took PAI, 34 who took DOAC and 9 who took VKA medications. The primary outcome measures were the transfusion rate and the pre- and postoperative haemoglobin (Hb) difference. The secondary outcome measures were the in-patient mortality and the rate of postoperative haematomas that needed operative treatment. A logistic/ordinal regression was performed considering the related variables to prevent cofounding occurring. The mean time to surgery was significantly longer for the DOAC and VKA groups when they were compared to the controls (none 14.7 ± 7.0 h; PAI 12.9 ± 6.7 h; DOAC 18.6 ± 6.3 h; VKA 19.4 ± 5.5 h; p p = 0.022), but the type of anticoagulative medication was not a significant predictor in the logistic regression. Anticoagulation with DOAC and grouped surgery times were positive predictors for a higher Hb difference in the patients who did not undergo an intraoperative blood transfusion (n = 159). Postoperative haematomas only occurred in patients taking anticoagulative medication (four cases in PAI group, and three cases in DOAC group), but the logistic regression showed that the anticoagulative medication had no effect. The in-patient mortality was significantly influenced by a high ASA grade (p = 0.008), but not by the type of anticoagulative medication in patients who were treated within 24 h. We conclude that the early endoprosthetic treatment of the anticoagulated hip fracture patient is safe, and a delayed surgical treatment is no longer justifiable
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