Two-parametric prescan calibration of gradient-induced sampling errors for rosette MRI.

PURPOSE: The aim of this study was to develop a simple, robust, and easy-to-use calibration procedure for correcting misalignments in rosette MRI k-space sampling, with the objective of producing images with minimal artifacts. METHODS: Quick automatic calibration scans were proposed for the beginning of the measurement to collect information on the time course of the rosette acquisition trajectory. A two-parameter model was devised to match the measured time-varying readout gradient delays and approximate the actual rosette sampling trajectory. The proposed calibration approach was implemented, and performance assessment was conducted on both phantoms and human subjects. RESULTS: The fidelity of phantom and in vivo images exhibited significant improvement compared with uncorrected rosette data. The two-parameter calibration approach also demonstrated enhanced precision and reliability, as evidenced by quantitative T 2 * $$ {\mathrm{T}}_2^{\ast } $$ relaxometry analyses. CONCLUSION: Adequate correction of data sampling is a crucial step in rosette MRI. The presented experimental results underscore the robustness, ease of implementation, and suitability for routine experimental use of the proposed two-parameter rosette trajectory calibration approach.

Adjuvant radiotherapy after brain metastasectomy: analysis of consecutive cohort of 118 patients from real world practice.

Background: The aim of this retrospective study is to analyze a consecutive cohort of brain metastasis (BM) patients treated off clinical trials through combination of surgery and radiotherapy over the last 15 years in a tertiary neurooncology center. Materials and methods: All BM patients operated between 2007-2019 received adjuvant linac-based radiotherapy categorized to whole brain radiotherapy (WBRT) and tumor bed stereotactic radiotherapy. Survival outcomes and local control was analyzed. Results: In total, 118 patients were enrolled, those with stereotactic radiotherapy (41%) had better baseline characteristics mirrored in longer overall survival (OS) [18 vs. 7.1 months, p < 0.001; hazard ratio (HR) 0.47, p = 0.004] with median follow-up of 58 months. Cumulative incidence for local, distant, and extracranial control was not significantly different between groups, with 12-month cumulative control of 22% vs. 18%, 44% vs. 29%, and 35% vs. 32% for stereotactic and WBRT group, respectively. WBRT was an independent factor for better distal brain control. Conclusions: Real world data demonstrating significantly better overall survival in patients treated with postoperative targeted radiotherapy compared with postoperative WBRT is presented, with no significant difference in cumulative incidence for local or distant brain control. The majority of patients with targeted radiotherapy had a fractionated dose schedule with outcomes comparable to single-dose radiation trials of postoperative targeted radiotherapy.

A pathological lesion or a postmortem artefact? An interdisciplinary approach to deal with an interesting early medieval case.

OBJECTIVE: This study evaluates a case of pseudopathology and the effects that postmortem taphonomic changes and environmental influences can have on bone. MATERIAL: A skeleton of a young male from the early medieval site Staré Mesto, dated to the 9th-10th century CE. METHODS: The skeletal remains were subjected to detailed macroscopic and X-ray examination, and then a CT scan and XRF analysis were performed. RESULTS: X-ray examination of the mandible revealed unusually dense structures, whose appearance was not consistent with any known pathology. Based on the results of CT scanning, it was hypothesized that these were cavities filled with alluvial sediment. X-ray fluorescence spectrometry (XRF), focusing on the determination of the silica content, revealed a high intensity of silica in the samples of the affected area of the bone. CONCLUSION: The hypothesis that the inclusions were composed of waterborne sediment was supported. SIGNIFICANCE: Although it is well known that soil can infiltrate bones buried in the ground, its appearance on plain radiographs is not that commonly known. The case illustrates the usefulness of differentiating true pathologies from postmortem alterations to avoid inappropriate interpretations. LIMITATIONS: No similar cases have been described. SUGGESTION FOR FURTHER RESEARCH: In palaeopathological evaluation, the use of multiple imaging and evaluative techniques should be implemented to differentiate pathological lesions from pseudopathology.

The role of exercise echocardiography in the diagnostics of heart failure with normal left ventricular ejection fraction.

AIMS: Few data are available on the exercise-induced abnormalities of myocardial function in patients with exertional dyspnoea and normal left ventricular ejection fraction (LV EF). The main aims of this study were to determine the prevalence of isolated exercise-induced heart failure with normal ejection fraction (HFNEF) and to assess whether disturbances in LV or right ventricular longitudinal systolic function are associated with the diagnosis of HFNEF. METHODS AND RESULTS: Eighty-four patients with exertional dyspnoea and normal LV EF and 14 healthy controls underwent spirometry, NT-proBNP plasma analysis, and exercise echocardiography. Doppler LV inflow and tissue mitral and tricuspid annular velocities were analysed at rest and immediately after the termination of exercise. Of the 30 patients with the evidence of HFNEF, 6 (20%) patients had only isolated exercise-induced HFNEF. When compared with the remaining patients, those with HFNEF had a significantly lower resting and exercise peak mitral annular systolic velocity (Sa) and the mitral annular velocity during atrial contraction, lower exercise peak mitral annular velocity at early diastole, and lower exercise peak systolic velocity of tricuspid annular motion. The multivariate logistic regression analysis including both parameters standardly defining HFNEF and the new Doppler variables potentially associated with the diagnosis of HFNEF revealed that NT-proBNP, LV mass index, left atrial volume index, and Sa significantly and independently predict the diagnosis of HFNEF. CONCLUSION: A significant proportion of patients require exercise to diagnose HFNEF. Sa appears to be a significant independent predictor of HFNEF, which may increase the diagnostic value of models utilizing the variables recommended by the European Society of Cardiology guidelines.

Penis as a primary site of an extraskeletal Ewing sarcoma: A case report.

RATIONALE: The Ewing sarcoma family of malignant tumors is a group of tumors characterized by morphologically similar round-cell neoplasms and by the presence of a common chromosomal translocation; Ewing sarcoma family of tumors typically occur in children and young adults between 4 to 15 years of age. The primary tumor usually originates in the bone, extraskeletal localization is rare. PATIENT CONCERN: We present a case report concerning a 32-year-old male patient with a primary involvement of the penis. DIAGNOSIS: The histopathology from the first penile biopsy showed a small-cell neuroendocrine carcinoma; however, that result was based on a sample obtained at a different facility than the Sarcoma Center, where the investigating pathologist did not have the adequate expertise. The patient then underwent a radical penectomy and a second reading of the histology was demanded after a radical penile amputation when Ewing sarcoma with R1 resection was confirmed. INTERVENTIONS: The patient was referred to the national Sarcoma Center, where - using a multidisciplinary approach - the treatment was started with curative intent. However, it was preceded by a non-standard initiation of the therapy due to the poor primary diagnosis. OUTCOMES: The non-standard therapy at the onset of the disease caused a poor prognosis of an otherwise curable diagnosis. Despite all that, the patient survived for a relatively long time. LESSONS: The treatment of sarcomas with atypical localizations should be conducted by an experienced multidisciplinary team in a center with experience in sarcoma treatment.

In silico study of pseudoprogression in glioblastoma: collaboration of radiologists and radiation oncologists in the estimation of extent of high dose RT region.

BACKGROUND AND AIM: Oncologists play a vital role in the interpretation of radiographic results in glioblastoma patients. Molecular pathology and information on radiation treatment protocols among others are all important for accurate interpretation of radiology images. One important issue that may arise in interpreting such images is the phenomenon of tumor "pseudoprogression"; oncologists need to be able to distinguish this effect from true disease progression.Exact knowledge about the location of high-dose radiotherapy region is needed for valid determination of pseudoprogression according to RANO (Response Assessment in Neuro-Oncology) criteria in neurooncology. The aim of the present study was to evaluate the radiologists' understanding of a radiotherapy high-dose region in routine clinical practice since radiation oncologists do not always report 3-dimensional isodoses when ordering follow up imaging. METHODS: Eight glioblastoma patients who underwent postresection radiotherapy were included in this study. Four radiologists worked with their pre-radiotherapy planning MR, however, they were blinded to RT target volumes which were defined by radiation oncologists according to current guidelines. The aim was to draw target volume for high dose RT fields (that is the region, where they would consider that there may be a pseudoprogression in future MRI scans). Many different indices describing structure differences were analyzed in comparison with original per-protocol RT target volumes. RESULTS: The median volume for RT high dose field was 277 ccm (range 218 to 401 ccm) as defined per protocol by radiation oncologist and 87 ccm (range 32-338) as defined by radiologists (median difference of paired difference 31%, range 15-112%). The Median Dice index of similarity was 0.46 (range 0.14 - 0.78), the median Hausdorff distance 25 mm. CONCLUSION: Continuing effort to improve education on specific procedures in RT and in radiology as well as automatic tools for exporting RT targets is needed in order to increase specificity and sensitivity in response evaluation.

WITHDRAWN: Autologous adipose tissue-derived stromal vascular fraction cells application in patients with osteoarthritis.

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