Microstructural Integrity of Salvaged Penumbra after Mechanical Thrombectomy.

BACKGROUND AND PURPOSE: There are sparse data on the microstructural integrity of salvaged penumbral tissue after mechanical thrombectomy of large-vessel occlusions. The aim of the study was to analyze possible microstructural alteration in the penumbra and their association with clinical symptoms as well as angiographic reperfusion success in patients undergoing mechanical thrombectomy. MATERIALS AND METHODS: All patients who underwent mechanical thrombectomy for large-vessel occlusions in the anterior circulation and who received an admission CT perfusion together with postinterventional DTIs were included (n = 65). Angiographic reperfusion success by means of modified Thrombolysis in Cerebral Infarction (mTICI) scale and clinical outcome were recorded. Microstructural integrity was assessed by DTI evaluating the mean diffusivity index within the salvaged gray matter of the former penumbra. RESULTS: The mean diffusivity index was higher in completely recanalized patients (mTICI 3: -0.001 ± 0.034 versus mTICI <3: -0.030 ± 0.055, P = .03). There was a positive correlation between the mean diffusivity index and NIHSS score improvement (r = 0.49, P = .003) and the mean diffusivity index was associated with midterm functional outcome (r = -0.37, P = .04) after adjustment for confounders. In mediation analysis, the mean diffusivity index and infarction growth mediated the association between reperfusion success and clinical outcomes. CONCLUSIONS: The macroscopic salvaged penumbra included areas of microstructural integrity changes, most likely related to the initial hypoperfusion. These abnormalities were found early after mechanical thrombectomy, were dependent on angiographic results, and correlated with the clinical outcome. When confirmed, these findings prompt the evaluation of therapies for protection of the penumbral tissue integrity.

[Acute abdominal trauma]. / Traumatisches akutes Abdomen.

BACKGROUND: In patients with multiple trauma, abdominal involvement is a particularly relevant injury pattern. Depending on the intensity and manner of injury, heterogeneous but often typical organ manifestations result. Knowledge of these injury patterns is essential for targeted diagnostics and treatment. OBJECTIVE: This review provides a presentation of typical forms of abdominal injury with appropriate radiological techniques and where applicable treatment. MATERIAL AND METHODS: Experiences and case examples from a supraregional trauma center are presented and discussed with the results of a Medline literature search and relevant parts of the german S3 guidelines on polytrauma. RESULTS: Traumatic abdominal injuries are subdivided into blunt and penetrating injuries. Among these groups, blunt trauma with splenic injury being most frequent followed by liver and kidney involvement. In penetrating abdominal injuries hollow visceral organs are most frequently affected. For diagnosis, ultrasound and with escalating injury severity, multidetector computed tomography (MDCT) are the most important methods. For years there has been an ongoing trend towards conservative management and interventional hemorrhage control. This is driven by improvements in imaging that enable a more precise classification and indications for subsequent treatment. CONCLUSION: Progress in radiology has led to an increasingly more important role for radiology in the management of traumatic abdominal injury. Therefore, it is crucial for the radiologist to gain interdisciplinary knowledge of the relevant trauma mechanisms and injury patterns of the severely injured patient in order to provide a treatment process that provides the optimal outcome.

Three-dimensional assessment of lower limb alignment: Accuracy and reliability.

INTRODUCTION: Three-dimensional (3D) surgical planning and patient-specific implants are becoming increasingly popular in orthopedics and trauma surgery. In contrast to the established and standardized alignment assessment on two-dimensional (2D) long standing radiographs (LSRs) there is neither a standardized nor a validated protocol for the analysis of 3D bone models of the lower limb. This study aimed to create a prerequisite for pre-operative planning. METHODS: According to 2D analysis and after meticulous research, 24 landmarks were defined on 3D bone models obtained from computed axial tomography (CT) scans for a 3D alignment assessment. Three observers with different experience levels performed the test three different times on three specimens. Intraobserver and interobserver variability of the landmarks and the intraclass correlation coefficient (ICC) of the resulting axes and joint angles were evaluated. RESULTS: Overall, the intraobserver and interobserver variability was low, with a mean deviation <5 mm for all landmarks. The ICC of all joint angles and axis deviations was >0.8, except for tibial torsion (ICC = 0.69). All knee joint angles showed excellent ICC (>0.95). CONCLUSIONS: Using the defined landmarks, a standardized 3D alignment assessment with low intraobserver and interobserver variability and high ICC values for the knee joint angles can be performed regardless of examiner's experience. The described method serves as a reliable standardized protocol for a 3D malalignment test of the lower limb. Three-dimensional pre-operative analysis might enhance understanding of deformities and lead to a new focus in surgical planning.

[Pretreatment mass casualty incident workflow analysis : Comparison of two level 1 trauma centers]. / Prätherapeutische Ablaufanalyse bei einem Massenanfall von Verletzten : Vergleich von zwei Traumazentren der höchsten Versorgungsstufe.

BACKGROUND: Mass casualty incidents (MCI) have particularly high demands on patient care processes but occur rather rarely in daily hospital routine. Therefore, it is common to use simulations to train staff and to optimize institutional processes. OBJECTIVES: Aim of study was to compare the pre-therapeutic in-house workflow of two differently structured level 1 trauma sites in the case of a simulated mass casualty incident (MCI). MATERIALS AND METHODS: A MCI of 70 patients was simulated by actors in a manner that was as realistic as possible. The on-site triage assigned 7 cases to trauma site A with relatively long in-house distances and 4 patients to an independent trauma site B in which these distances were relatively short. During in-house treatment, time intervals for reaching milestones were measured and compared using the Mann-Whitney U test. RESULTS: As no simultaneous patient arrival occurred, the Patient Distribution Matrix proved to be effective. Site A needed more time (minutes) from admission to endpoints (A: 31.85 ± 7.99; B: 21.62 ± 4.76; p = 0.059). In detail, the time intervals were particularly longer for both patient stay in trauma room (A: 8.46 ± 3.02; B: 2.73 ± 0.78, p < 0.01) and transfer time to the CT room (A: 1.81 ± 0.62; B: 0.06 ± 0.03, p < 0.01). A shorter stay in the CT room did not compensate these effects (A: 8.86 ± 1.84; B: 10.40 ± 2.89, p = 0.571). For both sites, image calculation and distribution were relatively time consuming (17.36 ± 3.05). CONCLUSIONS: Although short in-house distances accelerated pretherapeutic treatment processes significantly, both sites remained clearly within the "golden hour". The strongest potential bottleneck was the time interval until images were available at the endpoints.

[Changing the internal cost allocation (ICA) on DRG shares : Example of computed tomography in a university radiology setting]. / Umstellung der internen Leistungsverrechnung (ILV) auf DRG-Anteile : Beispiel der Computertomographie einer universitären Radiologie.

BACKGROUND: In hospitals, the radiological services provided to non-privately insured in-house patients are mostly distributed to requesting disciplines through internal cost allocation (ICA). In many institutions, computed tomography (CT) is the modality with the largest amount of allocation credits. OBJECTIVES: The aim of this work is to compare the ICA to respective DRG (Diagnosis Related Groups) shares for diagnostic CT services in a university hospital setting. MATERIALS AND METHODS: The data from four CT scanners in a large university hospital were processed for the 2012 fiscal year. For each of the 50 DRG groups with the most case-mix points, all diagnostic CT services were documented including their respective amount of GOÄ allocation credits and invoiced ICA value. As the German Institute for Reimbursement of Hospitals (InEK) database groups the radiation disciplines (radiology, nuclear medicine and radiation therapy) together and also lacks any modality differentiation, the determination of the diagnostic CT component was based on the existing institutional distribution of ICA allocations. RESULTS: Within the included 24,854 cases, 63,062,060 GOÄ-based performance credits were counted. The ICA relieved these diagnostic CT services by € 819,029 (single credit value of 1.30 Eurocent), whereas accounting by using DRG shares would have resulted in € 1,127,591 (single credit value of 1.79 Eurocent). The GOÄ single credit value is 5.62 Eurocent. CONCLUSIONS: The diagnostic CT service was basically rendered as relatively inexpensive. In addition to a better financial result, changing the current ICA to DRG shares might also mean a chance for real revenues. However, the attractiveness considerably depends on how the DRG shares are distributed to the different radiation disciplines of one institution.

Femoral marrow cavity bone harvesting used for arthroscopic refilling of misplaced or enlarged bone tunnels in revision ACL surgery: an arthroscopically supported technique with antegrade intramedullary bone harvesting by a reamer-irrigator-aspirator (RIA) system.

PURPOSE: In anterior cruciate ligament (ACL) revision surgery, refilling of misplaced or enlarged tunnels frequently requires bone harvesting from the iliac crest. Unfortunately, donor-site pain displays a relevant complication. In order to optimize patients' comfort, we developed a procedure combining minimally invasive intramedullary bone harvesting from the femur with arthroscopic tunnel refilling. METHODS: Patients with ACL reconstruction failure that were not eligible for one-step revision surgery but required tunnel refilling prior to the next ACL reconstruction were enrolled prospectively. Cancellous bone was harvested intramedullarily from the ipsilateral femur using the reamer-irrigator-aspirator system in a minimally invasive manner. Afterwards, the femoral and tibial tunnels were arthroscopically refilled using cones and push rods. Computer tomography (CT) analyses were carried out before and after the filling procedure. Pain levels were assessed during the entire follow-up. Patients undergoing iliac crest bone harvesting for other reasons served as a control group. Finally, the quality of the newly formed bone stock was evaluated in the subsequent ACL reconstruction procedure. RESULTS: Five patients were included during a 6-month period. Prior to refilling, tunnel analysis revealed a mean tunnel volume of 7.9 cm(3) at the femur [SD ± 5.3 cm(3)] and of 6.7 cm(3) [SD ± 5.1 cm(3)] at the tibia. The CT analyses further revealed that graft failure was predominantly caused by tunnel misplacement. Post-operatively, pain levels due to intramedullary bone harvesting were significantly lower compared to iliac crest bone harvesting at every analysed time point. Three to five months after tunnel filling, CT analyses showed sufficiently incorporated bone stocks with filling rates of 75 % femoral and 94 % tibial. ACL revision surgery was performed 4-5 months after tunnel filling without any complication. CONCLUSION: Intramedullary bone harvesting from the ipsilateral femur combined with arthroscopic refilling of the bone tunnels ensures a high-quality bone stock for further ACL reconstruction. The clinical relevance is shown by the feasibility of this technique and the significantly reduced pain levels during post-operative recovery.