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1.
Dis Esophagus ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38458619

RESUMEN

Previous studies have shown that surgical residents can safely perform a variation of complex abdominal surgeries when provided with adequate training, proper case selection, and appropriate supervision. Their outcomes are equivalent when compared to experienced board-certified surgeons. Our previously published training curriculum for robotic assisted minimally invasive esophagectomy already demonstrated a possible reduction in time to reach proficiency. However, esophagectomy is a technically challenging procedure and comes with high morbidity rates of up to 60%, making it difficult to provide opportunities to train surgical residents. We aimed to investigate if a surgical resident could safely perform complex esophageal surgery when a structured modular teaching curriculum is applied. A structured teaching program based on our previously published modular step-up approach was applied by two experienced board-certified esophageal surgeons. Our IRB-approved (Institutional Review Board) database was searched to identify all Ivor-Lewis esophagectomies performed by the selected surgical resident from August 2019 to July 2021. The cumulative sum method was used to analyze the learning curve of the surgical resident. Outcomes of patients operated by the resident were then compared to our overall cohort of open, hybrid, and robotic Ivor-Lewis esophagectomies from May 2016 to May 2020. The total cohort included 567 patients, of which 65 were operated by the surgical resident and 502 patients were operated by experienced esophageal cancer surgeons as the control group. For baseline characteristics, a significant difference for BMI (Body mass index) was observed, which was lower in the resident's group (25.5 kg/m2 vs. 26.8 kg/m2 (P = 0.046). A significant difference of American Society of Anesthesiologists- and Eastern Cooperative Oncology Group-scores was seen, and a subgroup analysis including all patients with American Society of Anesthesiologists I and Eastern Cooperative Oncology Group 0 was performed revealing no significant differences. Postoperative complications did not differ between groups. The anastomotic leak rate was 13.8% in the resident's cohort and 12% in the control cohort (P = 0.660). Major complications (Clavien-Dindo ≥ IIIb) occurred in 16.9% of patients in both groups. Oncological outcome, defined by harvested lymph nodes (35 vs. 32.33, P = 0.096), proportion of lymph node compliant performed operations (86.2% vs. 88.4%, P = 0.590), and R0-resection rate (96.9% vs. 96%, P = 0.766), was not compromised when esophagectomies were performed by the resident. The resident completed the learning curves after 39 cases for the total operating time, 38 cases for the thoracic operating time, 26 cases for the number of harvested lymph nodes, 29 cases for anastomotic leak rate, and finally 58 cases for the comprehensive complication index. For postoperative complications, no significant difference was seen between patients operated in the resident group versus the control group, with a third of patients being discharged with a textbook outcome in both cohorts. Furthermore, no difference in oncological quality of the resection was found, emphasizing safety and feasibility of our training program. A structured modular step-up for training a surgical resident to perform complex esophageal cancer surgery can successfully maintain patient safety and outcomes.

3.
Chirurgie (Heidelb) ; 95(4): 315-323, 2024 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-38273036

RESUMEN

Surgery faces significant challenges resulting from changes in medical education and the declining attractiveness of the surgical career path for aspiring doctors in the western world. For example, students' expectations of their future workplace have changed, with issues such as career planning uncertainties, an unbalanced work-life balance, and a lack of compatibility of family and occupation becoming increasingly more relevant. The entry of Generation Z into the workforce will also impact surgery. Although women comprise the largest proportion of graduates only a few opt for a career in surgery. The resulting shortage of young surgeons will negatively impact medical care in German surgical units. Intense competition for talents is already emerging in all medical specialties. Thus, hospitals and academic centers are taking various measures to counteract the impending staff shortage, such as summer schools or scholarships with work commitments. Furthermore, regional funding laws are being established. In addition, as there is a declining interest in surgical training, particularly during the course of medical studies, early integration of surgical skills is crucial to counteract this trend. For this reason, we have developed the "surgical track", designed to offer targeted innovative teaching concepts to get students attracted to surgery at an early stage. The "surgical track" is based on virtual reality (VR) and robotics. Students can practice operations and emergency scenarios through VR simulations and complete practical exercises with robotic systems. High-quality training concepts such as the "surgical track" can help to promote enthusiasm for surgery and impart knowledge at the same time, even if the long-term benefits still need to be evaluated. Through virtual simulations, robotic surgery and innovative teaching, students gain insights into visceral surgery that combine theoretical understanding and practical experience.


Asunto(s)
Educación Médica , Médicos , Procedimientos Quirúrgicos Robotizados , Realidad Virtual , Humanos , Femenino , Estudiantes
4.
PLOS Digit Health ; 2(6): e0000054, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37285355

RESUMEN

Certified Cancer Centers must present all patients in multidisciplinary tumor boards (MTB), including standard cases with well-established treatment strategies. Too many standard cases can absorb much of the available time, which can be unfavorable for the discussion of complex cases. In any case, this leads to a high quantity, but not necessarily a high quality of tumor boards. Our aim was to develop a partially algorithm-driven decision support system (DSS) for smart phones to provide evidence-based recommendations for first-line therapy of common urological cancers. To assure quality, we compared each single digital decision with recommendations of an experienced MTB and obtained the concordance.1873 prostate cancer patients presented in the MTB of the urological department of the University Hospital of Cologne from 2014 to 2018 have been evaluated. Patient characteristics included age, disease stage, Gleason Score, PSA and previous therapies. The questions addressed to MTB were again answered using DSS. All blinded pairs of answers were assessed for discrepancies by independent reviewers. Overall concordance rate was 99.1% (1856/1873). Stage specific concordance rates were 97.4% (stage I), 99.2% (stage II), 100% (stage III), and 99.2% (stage IV). Quality of concordance were independent of age and risk profile. The reliability of any DSS is the key feature before implementation in clinical routine. Although our system appears to provide this safety, we are now performing cross-validation with several clinics to further increase decision quality and avoid potential clinic bias.

6.
Br J Cancer ; 128(7): 1369-1376, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36717673

RESUMEN

BACKGROUND: Fast and accurate diagnostics are key for personalised medicine. Particularly in cancer, precise diagnosis is a prerequisite for targeted therapies, which can prolong lives. In this work, we focus on the automatic identification of gastroesophageal adenocarcinoma (GEA) patients that qualify for a personalised therapy targeting epidermal growth factor receptor 2 (HER2). We present a deep-learning method for scoring microscopy images of GEA for the presence of HER2 overexpression. METHODS: Our method is based on convolutional neural networks (CNNs) trained on a rich dataset of 1602 patient samples and tested on an independent set of 307 patient samples. We additionally verified the CNN's generalisation capabilities with an independent dataset with 653 samples from a separate clinical centre. We incorporated an attention mechanism in the network architecture to identify the tissue regions, which are important for the prediction outcome. Our solution allows for direct automated detection of HER2 in immunohistochemistry-stained tissue slides without the need for manual assessment and additional costly in situ hybridisation (ISH) tests. RESULTS: We show accuracy of 0.94, precision of 0.97, and recall of 0.95. Importantly, our approach offers accurate predictions in cases that pathologists cannot resolve and that require additional ISH testing. We confirmed our findings in an independent dataset collected in a different clinical centre. The attention-based CNN exploits morphological information in microscopy images and is superior to a predictive model based on the staining intensity only. CONCLUSIONS: We demonstrate that our approach not only automates an important diagnostic process for GEA patients but also paves the way for the discovery of new morphological features that were previously unknown for GEA pathology.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Redes Neurales de la Computación , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Adenocarcinoma/genética , Adenocarcinoma/patología , Hibridación in Situ , Receptores ErbB
7.
Langenbecks Arch Surg ; 407(7): 3069-3078, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35869334

RESUMEN

PURPOSE: This study is a secondary analysis of the IDOSP trial published in the Annals of Surgery 2020. The aim of this study was to examine the influence of stereo acuity on surgical performance in a laparoscopic training parkour with 3D- versus 4 K-2D-display technique. METHODS: The surgical performance of medical students (MS), non-board-certified surgeons (NBC), and board-certified surgeons (BC) was compared using 3D- versus 4 K-2D-display technique at a training parkour in a randomized cross-over trial. Stereo acuity was tested by TNO and Titmus Stereo tests. RESULTS: Eighty-nine participants were included in this sub-trial. The median stereo acuity for all participants, measured with the Titmus test, was 25 s arc, with TNO test 30 s arc. Higher quality stereo vision, measured with the Titmus test, correlated significantly with a reduced parkour time (r = 0.26, p = 0.02) and error (r = 0.21, p = 0.048) with the 3D screen. The TNO test did not correlate significantly with parkour performance. There was no statistically significant correlation between parkour time nor error and stereo acuity using the 4 K system (p > 0.457 respectively). Higher age showed a significant correlation with lower stereo acuity measured with TNO (r = 0.21, p = 0.014), but not with the Titmus test (r = - 0.7, p = 0.39). Seven percent of the group "NBC and BC" showed reduced stereo acuity > 120 s arc with the Titmus test and 3% with the TNO test. CONCLUSION: High-quality stereo vision is of utmost importance for surgical skills using a 3D-display system. This was most obvious for MS and for tasks that place particularly high demands on hand-eye coordination. The Titmus test was more precise than the TNO test to predict the benefit of a 3D monitor system. Experience and fine motor skills could partly compensate for a poorer stereo acuity. TRIAL REGISTRATION: This trial was registered at clinicaltrials.gov (trial number: NCT03445429, registered February 26, 2018).


Asunto(s)
Percepción de Profundidad , Procedimientos Quirúrgicos Mínimamente Invasivos , Cirujanos , Análisis y Desempeño de Tareas , Humanos , Estudios Cruzados , Percepción de Profundidad/fisiología , Agudeza Visual/fisiología
8.
BMC Med Educ ; 22(1): 295, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35443638

RESUMEN

BACKGROUND: The usage of smartphones in the daily clinical routine is an essential aspect however it seems that they also present an important distractor that needs to be evaluated. The aim of this prospective study was the evaluation of the influence of phone calls as distractors on the performance levels of medical students during an objective structured clinical examination (OSCE), simulating the normal clinical practice. METHODS: As the goal of an OSCE presents the examination of clinical skills of medical students in a realistic setting, more than 100 students recruited from the university hospital of Cologne participated in either OSCE I or II. During the OSCE I intravenous cannulation was simulated while OSCE II simulated an acute abdominal pain station. Participants had to perform each of these stations under two circumstances: a normal simulated OSCE and an OSCE station with phone call distraction. Their performance during both simulations was then evaluated. RESULTS: In OSCE I students achieved significantly more points in the intravenous cannulation station if they were not distracted by phone calls (M=6.44 vs M=5.95). In OSCE II students achieved significantly more points in the acute abdominal pain station if they were not distracted by phone calls (M=7.59 vs M=6.84). While comparing only those students that completed both stations in OSCE I/II participating students achieved significantly more points in both OSCE I and II if they were not distracted by phone calls. CONCLUSION: The presented data shows that phone call distraction decreases the performance level of medical students during an OSCE station. Therefore, it is an indicator that distraction especially for younger doctors should be held to a minimum. On a second note distraction should be integrated in the medical education system as it plays an important role in clinical routine.


Asunto(s)
Abdomen Agudo , Estudiantes de Medicina , Dolor Abdominal/diagnóstico , Dolor Abdominal/etiología , Competencia Clínica , Evaluación Educacional/métodos , Humanos , Examen Físico , Estudios Prospectivos
9.
Clin Cancer Res ; 28(8): 1712-1723, 2022 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-35191474

RESUMEN

PURPOSE: An increased risk to develop cancer is one of the most challenging negative side effects of long-term immunosuppression in organ transplant recipients and impaired cancer immunosurveillance is assumed as underlying mechanism. This study aims to elucidate transplant-related changes in the tumor immune microenvironment (TME) of cancer. EXPERIMENTAL DESIGN: Data from 123 organ transplant recipients (kidney, heart, lung, and liver) were compared with historic data from non-immunosuppressed patients. Digital image analysis of whole-section slides was used to assess abundance and spatial distribution of T cells and tertiary lymphoid structures (TLS) in the TME of 117 tumor samples. Expression of programmed cell death 1 ligand 1 (PD-L1) and human-leucocyte-antigen class I (HLA-I) was assessed on tissue microarrays. RESULTS: We found a remarkably reduced immune infiltrate in the center tumor (CT) regions as well as the invasive margins (IM) of post-transplant cancers. These differences were more pronounced in the IM than in the CT and larger for CD8+ T cells than for CD3+ T cells. The Immune-score integrating results from CT and IM was also lower in transplant recipients. Density of TLS was lower in cancer samples of transplant recipients. The fraction of samples with PD-L1 expression was higher in controls whereas decreased expression of HLA-I was more common in transplant recipients. CONCLUSIONS: Our study demonstrates the impact of immunosuppression on the TME and supports impaired cancer immunosurveillance as important cause of post-transplant cancer. Modern immunosuppressive protocols and cancer therapies should consider the distinct immune microenvironment of post-transplant malignancies.


Asunto(s)
Neoplasias , Estructuras Linfoides Terciarias , Antígeno B7-H1 , Antígenos de Histocompatibilidad Clase I , Humanos , Linfocitos Infiltrantes de Tumor , Monitorización Inmunológica , Neoplasias/etiología , Neoplasias/metabolismo , Microambiente Tumoral
10.
Zentralbl Chir ; 147(1): 26-34, 2022 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-33782929

RESUMEN

For quite some time, the development and implementation of online teaching has been a controversial issue in surgical education for the degree in medicine. This has become more important with the progression of digitalisation and not least as a result of the current pandemic. It is becoming increasingly urgent to establish the opportunities and limits of online teaching, which has already proved successful under the current developmental pressure, and there are promising concepts. This article addresses the framework and the various online teaching formats in surgery, and illustrates the interplay between technical feasibility, practical experience, and didactic objectives.


Asunto(s)
COVID-19 , Educación a Distancia , Humanos , Pandemias , Enseñanza
11.
Surg Endosc ; 36(6): 4376-4385, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34750707

RESUMEN

BACKGROUND: The use of 3D technique compared to high-resolution 2D-4K-display technique has been shown to optimize spatial orientation and surgical performance in laparoscopic surgery. Since women make up an increasing amount of medical students and surgeons, this study was designed to investigate whether one gender has a greater benefit from using a 3D compared to a 4K-display system. METHODS: In a randomized cross-over trial, the surgical performance of male and female medical students (MS), non-board certified surgeons (NBCS), and board certified surgeons (BCS) was compared using 3D- vs. 4K-display technique at a minimally invasive training parkour with multiple surgical tasks and repetitions. RESULTS: 128 participants (56 women, 72 men) were included. Overall parkour time in seconds was 3D vs. 4K for all women 770.7 ± 31.9 vs. 1068.1 ± 50.0 (p < 0.001) and all men 664.5 ± 19.9 vs. 889.7 ± 31.2 (p < 0.001). Regarding overall mistakes, participants tend to commit less mistakes while using the 3D-vision system, showing 10.2 ± 1.1 vs. 13.3 ± 1.3 (p = 0.005) for all women and 9.6 ± 0.7 vs. 12.2 ± 1.0 (p = 0.001) for all men. The benefit of using a 3D system, measured by the difference in seconds, was for women 297.3 ± 41.8 (27.84%) vs. 225.2 ± 23.3 (25.31%) for men (p = 0.005). This can be confirmed in the MS group with 327.6 ± 65.5 (35.82%) vs. 249.8 ± 33.7 (32.12%), p = 0.041 and in the NBCS group 359 ± 52.4 (28.25%) vs. 198.2 ± 54.2 (18.62%), p = 0.003. There was no significant difference in the BCS group. CONCLUSION: 3D laparoscopic display technique optimizes surgical performance compared to the 2D-4K technique for both women and men. The greatest 3D benefit was found for women with less surgical experience. As a possible result of surgical education, this gender specific difference disappears with higher grade of experience. Using a 3D-vision system could facilitate surgical apprenticeship, especially for women.


Asunto(s)
Laparoscopía , Estudiantes de Medicina , Competencia Clínica , Estudios Cruzados , Femenino , Humanos , Imagenología Tridimensional , Laparoscopía/métodos , Masculino
12.
J Cancer Res Clin Oncol ; 148(5): 1223-1234, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34223965

RESUMEN

BACKGROUND: Patients with locally advanced esophageal or gastroesophageal adenocarcinoma benefit from multimodal therapy concepts including neoadjuvant chemoradiation (nCRT), respectively, perioperative chemotherapy (pCT). However, it remains unclear which treatment is superior concerning postoperative morbidity. METHODS: In this study, we compared the postsurgical survival (30-day/90-day/1-year mortality) (primary endpoint), treatment response, and surgical complications (secondary endpoints) of patients who either received nCRT (CROSS protocol) or pCT (FLOT protocol) due to esophageal/gastroesophageal adenocarcinoma. Between January 2013 and December 2017, 873 patients underwent Ivor Lewis esophagectomy in our high-volume center. 339 patients received nCRT and 97 underwent pCT. After 1:1 propensity score matching (matching criteria: sex, age, BMI, ASA score, and Charlson score), 97 patients per subgroup were included for analysis. RESULTS: After matching, tumor response (ypT/ypN) did not differ significantly between nCRT and pCT (p = 0.118, respectively, p = 0.174). Residual nodal metastasis occurred more often after pCT (p = 0.001). Postsurgical mortality was comparable within both groups. No patient died within 30 or 90 days after surgery while the 1-year survival rate was 72.2% for nCRT and 68.0% for pCT (p = 0.47). Only grade 3a complications according to Clavien-Dindo were increased after pCT (p = 0.04). There was a trend towards a higher rate of pylorospasm within the pCT group (nCRT: 23.7% versus pCT: 37.1%) (p = 0.061). Multivariate analysis identified pCT, younger age, and Charlson score as independent variables for pylorospasm. CONCLUSION: Both nCRT and pCT are safe and efficient within the multimodal treatment of esophageal/gastroesophageal adenocarcinoma. We did not observe differences in postoperative morbidity. However, functional aspects such as gastric emptying might be more frequent after pCT.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Adenocarcinoma/patología , Quimioradioterapia , Neoplasias Esofágicas/cirugía , Esofagectomía , Unión Esofagogástrica/patología , Humanos , Terapia Neoadyuvante , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento
13.
Chirurg ; 92(10): 929-935, 2021 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-34448904

RESUMEN

BACKGROUND: The outbreak of the coronavirus disease 2019 (COVID-19) pandemic imposed limitations for elective surgery, impacting the associated hospital standards worldwide. As certain treatment windows must be adhered to in oncological surgery, the limited intensive care unit (ICU) capacity had to be critically distributed in order to do justice to both acutely ill and oncology patients. This manuscript summarizes the impact of COVID-19 on the management of oncological surgery of the upper gastrointestinal tract and particularly esophageal surgery in German medical centers. MATERIAL AND METHODS: A survey of German centers for esophageal surgery was performed on the impact of COVID-19 on operative management for esophageal surgery during the first lockdown. After inspection, assessment, critical analysis and interpretation, the results were compared to the international literature. RESULTS AND DISCUSSION: Initial recommendations of international societies warned for caution and restraint regarding interventions of the upper gastrointestinal tract that were not absolutely necessary. Oncological surgery should be performed under strict restrictions, especially only after negative testing for COVID-19 and only with sufficiently available personal protective equipment for the personnel. Furthermore, minimally invasive procedures were preferably not recommended. In diseases with alternative treatment options, such as definitive chemoradiotherapy of esophageal squamous cell carcinoma, these should be given priority when possible. In the further development of the pandemic, it was shown that due to a high standardization of preoperative management, postoperative results comparable to pre-pandemic times could be achieved particularly with respect to the diagnostics of infections.


Asunto(s)
COVID-19 , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Tracto Gastrointestinal Superior , Prueba de COVID-19 , Control de Enfermedades Transmisibles , Neoplasias Esofágicas/cirugía , Humanos , SARS-CoV-2
14.
Cancers (Basel) ; 13(11)2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34072549

RESUMEN

Pancreatic cancer features elaborate mechanisms of immune evasion. The potential of new immune molecules was explored to restore the antitumor immune response. If these immune molecules are associated with poor survival, specific drugs could take effect. Here, we analyze the expression of VISTA, LAG3, IDO, and TIM3 on tumor-infiltrating lymphocytes (TILs) and its impact on patient survival. We analyzed 153 pancreatic cancer patients from the prospectively managed database of the multicentered PANCALYZE study. Immunohistochemistry on a tissue microarray assessed VISTA, LAG3, IDO, and TIM3 expression of TILs from the patients undergoing primary resection. Complementarily, we analyzed publicly available transcriptomic data (n = 903). Successful completion of chemotherapy, and lymph node status were independent predictors of survival in the multivariate analysis of the clinicopathologic parameters. Fifteen tumors were exclusively VISTA-positive, thirteen tumors expressed VISTA together with TIM3, and ten tumors expressed VISTA together with IDO. Patients featuring tumors with high numbers of IDO-positive TILs had better patient survival (p = 0.037). VISTA, LAG3, and TIM3 expression did not correlate with survival. The analysis of publicly available data did not show survival differences. Tumors rarely co-express more than two immune molecules at the same time, and VISTA is most frequently co-expressed. Although IDO generally inhibits T-cell proliferation, a high expression of IDO was associated with improved survival. We expect immune checkpoint inhibitors against VISTA, LAG3, and TIM3 to be inefficient in a clinical application.

15.
World J Gastrointest Oncol ; 13(6): 612-624, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34163577

RESUMEN

BACKGROUND: There is no established correlation between 24-h esophageal pH-metry (Eso-pH) and the new laryngopharyngeal pH-monitoring system (Restech) as only small case series exist. Eso-pH was not designed to detect laryngopharyngeal reflux (LPR) and Restech may detect LPR better. We have previously published a dataset using the two techniques in a large patient collective with gastroesophageal reflux disease. Anatomically, patients after esophagectomy were reported to represent an ideal human reflux model as no reflux barrier exists. AIM: To use a human reflux model to examine our previously published correlation in these patients. METHODS: Patients after Ivor Lewis esophagectomy underwent our routine follow-up program with surveillance endoscopies, computed tomography scans and further exams following surgery. Only patients with a complete check-up program and reflux symptoms were offered inclusion into this prospective study and evaluated using Restech and simultaneous Eso-pH. Subsequently, the relationship between the two techniques was evaluated. RESULTS: A total of 43 patients from May 2016 - November 2018 were included. All patients presented with mainly typical reflux symptoms such as heartburn (74%), regurgitation (84%), chest pain (58%), and dysphagia (47%). Extraesophageal symptoms such as cough, hoarseness, asthma symptoms, and globus sensation were also present. Esophageal 24-hour pH-metry was abnormal in 88% of patients with a mean DeMeester Score of 229.45 [range 26.4-319.5]. Restech evaluation was abnormal in 61% of cases in this highly selective patient cohort. All patients with abnormal supine LPR were also abnormal for supine esophageal reflux measured by conventional Eso-pH. CONCLUSION: Patients following esophagectomy and reconstruction with gastric interposition can ideally serve as a human reflux model. Interestingly, laryngopharyngeal reflux phases occur mainly in the upright position. In this human volume-reflux model, results of simultaneous esophageal and laryngopharyngeal (Restech) pH-metry showed 100% correlation as being explicable by one of our reflux scenarios.

16.
Rapid Commun Mass Spectrom ; 35(3): e8963, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33002258

RESUMEN

RATIONALE: A new compact thermal ionization (TI) mass spectrometer, for the isotope ratio analysis of the elements relevant to nuclear applications, has been designed and developed. The new development offers superior performance in terms of sensitivity, precision and a compact footprint in comparison with the conventional one. The main feature of the TI mass spectrometer is the magnetic sector analyser with a sector radius of 20 cm (instead of 30/27 cm in conventional/commercial geometry). An apparent reduction in dispersion has been adequately compensated by employing variable dispersion zoom optics (VDZO). METHODS: The theoretical calculations were validated by computer simulations using SIMION 7.0, leading to the finalization of the mechanical design. Experimental evaluation was carried out using standard TI mass spectrometric methodology to determine the parameters, namely peak flatness, mass range, sensitivity, abundance sensitivity, resolution and precision. RESULTS: The multi-collector resolution was 496, and the maximum mass was m/z 382. The sensitivity for uranium was found to be better than 1 ion for 500 atoms, and an abundance sensitivity of 50 ppm at m/z 237 was obtained. The peak flatness for the uranium peak was 3200 ppm of mass. The precision for the isotopic ratio 235 U/238 U was found to be 0.05% for the U200 standard. CONCLUSIONS: A new compact TI mass spectrometer with a 20 cm sector radius has been designed and developed. The advantage of larger dispersion produced by the VDZO (developed in-house) was exploited when deciding the 20 cm sector radius. The comparison study with the conventional TI mass spectrometer shows an enhanced (1.5×) sensitivity and an improved precision (0.05%) for the 235 U/238 U ratio of U200.

17.
Transplant Proc ; 53(3): 786-792, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32981693

RESUMEN

BACKGROUND: Health-related quality of life (HRQL), fatigue, anxiety, and depression are crucial for the living kidney donor (LKD). Follow-up data for HRQL of LKDs comparing surgical techniques, especially regarding hand-assisted retroperitoneoscopic donor nephrectomy (HARP), are sparse. The aim of this study was to evaluate the influence of abdominal wall trauma minimized by HARP in comparison to open anterior approach donor nephrectomy (AA) on HRQL and additional psychosocial aspects of LKDs during the long-term follow-up. MATERIAL AND METHODS: This is a cross-sectional study comparing psychosocial aspects of LKD between HARP and AA. RESULTS: This study included 100 LKDs (68 HARP, 28 AA, and 4 were excluded secondary to incomplete data). The time to follow-up was 22.6 ± 11.7 (HARP) vs 58.7 ± 13.9 (AA) months (P < .005). Complications ≥3a° due to Clavien-Dindo classification was 0% in both groups. There were higher scores in all physical aspects for HARP donors vs AA donors at that time (physical function: 89.8 ± 14.6 vs 80.0 ± 19.9, P = .008, and the physical component score: 53.9 ± 7.6 vs 48.6 ± 8.5, P = .006). One year later (follow-up time + 12 months), HRQL for HARP donors was still higher. Mental items showed no significant differences. HARP donors showed better physical scores compared to the age-matched nondonor population (AA donors had lower scores). Neither the Multidimensional Fatigue Inventory-20 (MFI-20) or the Hospital Anxiety and Depression Scale (HADS) showed any differences between the 2 groups. Fatigue scores were higher for HARP and for AA compared to the age-matched population. CONCLUSIONS: LKDs undergoing HARP showed better physical performance as part of HRQL in the long-term follow-up.


Asunto(s)
Laparoscópía Mano-Asistida/métodos , Trasplante de Riñón , Nefrectomía/métodos , Espacio Retroperitoneal/cirugía , Recolección de Tejidos y Órganos/métodos , Adulto , Estudios Transversales , Femenino , Humanos , Riñón/cirugía , Donadores Vivos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Rendimiento Físico Funcional , Periodo Posoperatorio , Calidad de Vida , Tiempo
18.
Surg Endosc ; 35(9): 5338-5351, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32968918

RESUMEN

BACKGROUND: Minimally invasive single-port surgery is always associated with large incisions up to 2-3 cm, complicated handling due to the lack of triangulation, and instrument crossing. The aim of this prospective study was to report how medical students without any laparoscopic experience perform several laparoscopic tasks (rope pass, paper cut, peg transfer, recapping, and needle threading) with the new SymphonX single-port platform and to examine the learning curves in comparison to the laparoscopic multi-port technique. METHODS: A set of 5 laparoscopic skill tests (Rope Pass, Paper cut, Peg Transfer, Recapping, Needle Thread) were performed with 3 repetitions. Medical students performed all tests with both standard laparoscopic instruments and the new platform. Time and errors were recorded. RESULTS: A total of 114 medical students (61 females) with a median age of 23 years completed the study. All subjects were able to perform the skill tests with both standard laparoscopic multi-port and the single-port laparoscopic system and were able to significantly improve their performance over the three trials for all five tasks-rope pass (p < 0.001), paper cut (p < 0.001), peg transfer (p < 0.001), needle threading (p < 0.001), and recapping (p < 0.001). In 3 out of 5 tasks, medical students performed the tasks faster using the standard multi-port system-rope pass (p < 0.001), paper cut (p < 0.001), and peg transfer (p < 0.001). In the task recapping, medical students performed the task faster using the new single-port system (p = 0.003). In the task needle threading, there was no significant difference between the standard multi-port system and the new single-port system (p > 0.05). CONCLUSION: This is the first study analyzing learning curves of the commercially available SymphonX platform for abdominal laparoscopic surgery when used by novices. The learning curve and the error rate are promising.


Asunto(s)
Laparoscopía , Curva de Aprendizaje , Adulto , Competencia Clínica , Femenino , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos , Estudios Prospectivos , Adulto Joven
19.
Cancer Immunol Immunother ; 70(4): 893-907, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33006650

RESUMEN

Thermal ablative therapies are standard treatments for localized hepatocellular carcinoma (HCC). In addition to local tumor destruction, ablation leads to abscopal effects in distant lesions most likely mediated by an anti-tumor immune response. Although microwave ablation (MWA) is increasingly substituting other ablative techniques, its systemic immunostimulatory effects are poorly studied. We analyzed tumor-specific immune responses in peripheral blood of HCC patients after thermal ablation with regard to T cell responses and disease outcome. While comprehensive flow cytometric analyses in sequential samples of a prospective patient cohort (n = 23) demonstrated only moderate effects of MWA on circulating immune cell subsets, fluorospot analyses of specific T cell responses against seven tumor-associated antigens (TTAs) revealed de-novo or enhanced tumor-specific immune responses in 30% of patients. This anti-tumor immune response was related to tumor control as Interferon-y and Interleukin-5 T cell responses against TAAs were more frequent in patients with a long-time remission (> 1 year) after MWA (7/16) compared to patients suffering from an early relapse (0/13 patients) and presence of tumor-specific T cell response (IFN-y and/or IL-5) was associated to longer progression-free survival (27.5 vs. 10.0 months). Digital image analysis of immunohistochemically stained archival HCC samples (n = 18) of patients receiving combined MWA and resection revealed a superior disease-free survival of patients with high T cell abundance at the time of thermal ablation (37.4 vs. 13.1 months). Our data demonstrates remarkable immune-related effects of MWA in HCC patients and provides additional evidence for a combination of local ablation and immunotherapy in this challenging disease.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Ablación por Catéter/métodos , Inmunidad/inmunología , Neoplasias Hepáticas/inmunología , Microondas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia
20.
PLoS One ; 15(8): e0232341, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32845892

RESUMEN

BACKGROUND: Both laparoscopic surgery and computer games make similar demands on eye-hand coordination and visuospatial cognitive ability. A possible connection between both areas could be used for the recruitment and training of future surgery residents. AIM: The goal of this study was to investigate whether gaming skills are associated with better laparoscopic performance in medical students. METHODS: 135 medical students (55 males, 80 females) participated in an experimental study. Students completed three laparoscopic tasks (rope pass, paper cut, and peg transfer) and played two custom-designed video games (2D and 3D game) that had been previously validated in a group of casual and professional gamers. RESULTS: There was a small significant correlation between performance on the rope pass task and the 3D game, Kendall's τ(111) = -.151, P = .019. There was also a small significant correlation between the paper cut task and points in the 2D game, Kendall's τ(102) = -.180, P = .008. Overall laparoscopic performance was also significantly correlated with both the 3D game, Kendall's τ(112) = -.134, P = .036, and points in the 2D game, Kendall's τ(113) = -.163, P = .011. However, there was no significant correlation between the peg transfer task and both games (2D and 3D game), P = n.s.. CONCLUSION: This study provides further evidence that gaming skills may be an advantage when learning laparoscopic surgery.


Asunto(s)
Competencia Clínica , Laparoscopía , Cirujanos , Juegos de Video , Adulto , Simulación por Computador , Femenino , Alemania , Humanos , Laparoscopía/psicología , Curva de Aprendizaje , Masculino , Destreza Motora , Desempeño Psicomotor , Factores Sexuales , Procesamiento Espacial , Estudiantes de Medicina/psicología , Cirujanos/psicología , Análisis y Desempeño de Tareas , Juegos de Video/psicología , Adulto Joven
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