Optimizing clinical outcomes for bronchoscopic lung volume reduction with Zephyr® valves.

Bronchoscopic lung volume reduction treatment with Zephyr one-way valves is an effective guideline-based treatment option for patients with severe emphysema and hyperinflation. However, in some cases the treatment response is less than anticipated or there might be a loss of initial treatment effect. Reasons for the lack of response can include incorrect assessment of collateral ventilation, improper valve placement, or patient related factors. Loss of initial benefit can be due to granulation tissue formation and subsequent valve dysfunction, or there may be side effects such as excessive coughing or infectious problems. Careful follow-up after treatment with valves is important and evaluation with a CT scan and/or bronchoscopy is helpful if there is no improvement after treatment or loss of initial benefit. This paper aims to describe the most important causes and provide a strategy of how to approach and manage these patients.

Cohort study of patients with advanced cancer: outcomes associated with duration of antibiotic therapy for non-ventilator hospital-acquired pneumonia.

In this single-center observational study of 118 older adults with advanced cancer who developed non-ventilator hospital-acquired pneumonia, prolonged antibiotic durations (8-14 and ≥15 vs ≤7 d) were not associated with reduced adjusted odds of 90-day all-cause readmission or death. These data may inform antimicrobial stewardship efforts in palliative care settings.

The Liver Tumor Segmentation Benchmark (LiTS).

In this work, we report the set-up and results of the Liver Tumor Segmentation Benchmark (LiTS), which was organized in conjunction with the IEEE International Symposium on Biomedical Imaging (ISBI) 2017 and the International Conferences on Medical Image Computing and Computer-Assisted Intervention (MICCAI) 2017 and 2018. The image dataset is diverse and contains primary and secondary tumors with varied sizes and appearances with various lesion-to-background levels (hyper-/hypo-dense), created in collaboration with seven hospitals and research institutions. Seventy-five submitted liver and liver tumor segmentation algorithms were trained on a set of 131 computed tomography (CT) volumes and were tested on 70 unseen test images acquired from different patients. We found that not a single algorithm performed best for both liver and liver tumors in the three events. The best liver segmentation algorithm achieved a Dice score of 0.963, whereas, for tumor segmentation, the best algorithms achieved Dices scores of 0.674 (ISBI 2017), 0.702 (MICCAI 2017), and 0.739 (MICCAI 2018). Retrospectively, we performed additional analysis on liver tumor detection and revealed that not all top-performing segmentation algorithms worked well for tumor detection. The best liver tumor detection method achieved a lesion-wise recall of 0.458 (ISBI 2017), 0.515 (MICCAI 2017), and 0.554 (MICCAI 2018), indicating the need for further research. LiTS remains an active benchmark and resource for research, e.g., contributing the liver-related segmentation tasks in http://medicaldecathlon.com/. In addition, both data and online evaluation are accessible via https://competitions.codalab.org/competitions/17094.

Prevalence and treatment of postobstructive pneumonia among older adults with advanced cancer.

Among 124 older adults with advanced cancer who were hospitalized with pneumonia, 7.3% met criteria for postobstructive pneumonia. There were no differences in antibiotic duration, antibiotic spectrum, 30-day and 90-day readmissions, or mortality between those with and without postobstructive pneumonia. Bacteria were identified in 5 patients with postobstructive pneumonia.

Medical Students' Knowledge of Plastic Surgery as a Reflection of the Public Perception.

Plastic surgery is a broad field that requires a mixed skillset. Therefore, it is important that students be exposed to all its various subspecialties to make informed career decisions and to properly refer patients in different clinical situations. A nationwide survey was conducted of Israeli medical students to investigate their knowledge and perceptions regarding the field of plastic surgery and its subspecialties, and the impact of a clinical rotation in plastic surgery on these factors. A total of 300 subjects responded. Approximately, 61% of the cohort was female and 70% were enrolled in a 6-year program. About one-third stated that their field of interest was surgical rather than medical. Significant variability was noted in the accuracy of responses to questions about different procedures encompassed in the scope of plastic surgery. Although 90% of the students were aware of some common plastic surgery procedures that are also often thought to be well known to the public, only 50% were able to correctly identify lesser-known surgeries performed by plastic surgeons. Knowledge about plastic surgery was unrelated to an interest in the field. We recommend adjusting preclinical instruction and clinical rotations in plastic surgery to better prepare students to select a specialty best suited to their future goals, as well as to improve their ability to refer patients to other specialists as necessary.

Artificial Intelligence Tool for Assessment of Indeterminate Pulmonary Nodules Detected with CT.

Background Limited data are available regarding whether computer-aided diagnosis (CAD) improves assessment of malignancy risk in indeterminate pulmonary nodules (IPNs). Purpose To evaluate the effect of an artificial intelligence-based CAD tool on clinician IPN diagnostic performance and agreement for both malignancy risk categories and management recommendations. Materials and Methods This was a retrospective multireader multicase study performed in June and July 2020 on chest CT studies of IPNs. Readers used only CT imaging data and provided an estimate of malignancy risk and a management recommendation for each case without and with CAD. The effect of CAD on average reader diagnostic performance was assessed using the Obuchowski-Rockette and Dorfman-Berbaum-Metz method to calculate estimates of area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Multirater Fleiss κ statistics were used to measure interobserver agreement for malignancy risk and management recommendations. Results A total of 300 chest CT scans of IPNs with maximal diameters of 5-30 mm (50.0% malignant) were reviewed by 12 readers (six radiologists, six pulmonologists) (patient median age, 65 years; IQR, 59-71 years; 164 [55%] men). Readers' average AUC improved from 0.82 to 0.89 with CAD (P < .001). At malignancy risk thresholds of 5% and 65%, use of CAD improved average sensitivity from 94.1% to 97.9% (P = .01) and from 52.6% to 63.1% (P < .001), respectively. Average reader specificity improved from 37.4% to 42.3% (P = .03) and from 87.3% to 89.9% (P = .05), respectively. Reader interobserver agreement improved with CAD for both the less than 5% (Fleiss κ, 0.50 vs 0.71; P < .001) and more than 65% (Fleiss κ, 0.54 vs 0.71; P < .001) malignancy risk categories. Overall reader interobserver agreement for management recommendation categories (no action, CT surveillance, diagnostic procedure) also improved with CAD (Fleiss κ, 0.44 vs 0.52; P = .001). Conclusion Use of computer-aided diagnosis improved estimation of indeterminate pulmonary nodule malignancy risk on chest CT scans and improved interobserver agreement for both risk stratification and management recommendations. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Yanagawa in this issue.

Research Productivity among Plastic Surgeons in the State of Israel: h-index and M-quotient Assessment.

The h-index has been proven in the US and Canada to be a solid tool to assess the quality and impact of individual scientific work in the field of plastic surgery. M-quotient is an additional metric that mitigates the h-index's inherent bias toward more seasoned researchers. The objective of this study was evaluating the relationship between h-index and M-quotient and research productivity among plastic surgeons in the state of Israel. METHODS: A list of all Israeli board-certified plastic surgeons registered in the Israeli Society of Plastic and Aesthetic Surgery was obtained from the organization's website. Relevant demographic and academic factors of each surgeon were retrieved. The Scopus database was queried to determine each surgeon's h-index and M-quotient, among other bibliometric parameters. RESULTS: Our study included 173 plastic surgeons, 90% of whom were men. In total, 49.7% were working in academically affiliated hospitals; 14.4% of the surgeons had an academic rank. The mean h-index was 6.13; mean M-quotient was 0.27. Statistical analysis demonstrated a positive correlation between total number of publications (P < 0.0001), total number of citations (P < 0.0001), the surgeon's seniority (P < 0.0001), academic rank (P = 0.007), appointed as past/present plastic surgery department director (P < 0.0001), and working in an academic affiliated hospital (P < 0.025). The same parameters were found to have a positive correlation with M-quotient. CONCLUSIONS: The h-index is an effective measure to compare plastic surgeons' research productivity in Israel. M-quotient is an ancillary tool for the assessment of research productivity among plastic surgeons, with the advent of neutralizing the surgeon's seniority.

Predicting Lymph Node Metastasis in Non-small Cell Lung Cancer: Prospective External and Temporal Validation of the HAL and HOMER Models.

BACKGROUND: Two models, the Help with the Assessment of Adenopathy in Lung cancer (HAL) and Help with Oncologic Mediastinal Evaluation for Radiation (HOMER), were recently developed to estimate the probability of nodal disease in patients with non-small cell lung cancer (NSCLC) as determined by endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA). The objective of this study was to prospectively externally validate both models at multiple centers. RESEARCH QUESTION: Are the HAL and HOMER models valid across multiple centers? STUDY DESIGN AND METHODS: This multicenter prospective observational cohort study enrolled consecutive patients with PET-CT clinical-radiographic stages T1-3, N0-3, M0 NSCLC undergoing EBUS-TBNA staging. HOMER was used to predict the probability of N0 vs N1 vs N2 or N3 (N2|3) disease, and HAL was used to predict the probability of N2|3 (vs N0 or N1) disease. Model discrimination was assessed using the area under the receiver operating characteristics curve (ROC-AUC), and calibration was assessed using the Brier score, calibration plots, and the Hosmer-Lemeshow test. RESULTS: Thirteen centers enrolled 1,799 patients. HAL and HOMER demonstrated good discrimination: HAL ROC-AUC = 0.873 (95%CI, 0.856-0.891) and HOMER ROC-AUC = 0.837 (95%CI, 0.814-0.859) for predicting N1 disease or higher (N1|2|3) and 0.876 (95%CI, 0.855-0.897) for predicting N2|3 disease. Brier scores were 0.117 and 0.349, respectively. Calibration plots demonstrated good calibration for both models. For HAL, the difference between forecast and observed probability of N2|3 disease was +0.012; for HOMER, the difference for N1|2|3 was -0.018 and for N2|3 was +0.002. The Hosmer-Lemeshow test was significant for both models (P = .034 and .002), indicating a small but statistically significant calibration error. INTERPRETATION: HAL and HOMER demonstrated good discrimination and calibration in multiple centers. Although calibration error was present, the magnitude of the error is small, such that the models are informative.

Severe respiratory viral infection induces procalcitonin in the absence of bacterial pneumonia.

INTRODUCTION: Procalcitonin expression is thought to be stimulated by bacteria and suppressed by viruses via interferon signalling. Consequently, during respiratory viral illness, clinicians often interpret elevated procalcitonin as evidence of bacterial coinfection, prompting antibiotic administration. We sought to evaluate the validity of this practice and the underlying assumption that viral infection inhibits procalcitonin synthesis. METHODS: We conducted a retrospective cohort study of patients hospitalised with pure viral infection (n=2075) versus bacterial coinfection (n=179). The ability of procalcitonin to distinguish these groups was assessed. In addition, procalcitonin and interferon gene expression were evaluated in murine and cellular models of influenza infection. RESULTS: Patients with bacterial coinfection had higher procalcitonin than those with pure viral infection, but also more severe disease and higher mortality (p<0.001). After matching for severity, the specificity of procalcitonin for bacterial coinfection dropped substantially, from 72% to 61%. In fact, receiver operating characteristic curve analysis showed that procalcitonin was a better indicator of multiple indices of severity (eg, organ failures and mortality) than of coinfection. Accordingly, patients with severe viral infection had elevated procalcitonin. In murine and cellular models of influenza infection, procalcitonin was also elevated despite bacteriologic sterility and correlated with markers of severity. Interferon signalling did not abrogate procalcitonin synthesis. DISCUSSION: These studies reveal that procalcitonin rises during pure viral infection in proportion to disease severity and is not suppressed by interferon signalling, in contrast to prior models of procalcitonin regulation. Applied clinically, our data suggest that procalcitonin represents a better indicator of disease severity than bacterial coinfection during viral respiratory infection.

Quantification of bronchoalveolar neutrophil extracellular traps and phagocytosis in murine pneumonia.

The past two decades have witnessed a resurgence in neutrophil research, inspired in part by the discovery of neutrophil extracellular traps (NETs) and their myriad roles in health and disease. Within the lung, dysregulation of neutrophils and NETosis have been linked to an array of diseases including pneumonia, cystic fibrosis, acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), and severe asthma. However, our understanding of pathologic neutrophil responses in the lung remains incomplete. Two methodologic issues have contributed to this gap: first, an emphasis on studying neutrophils from blood rather than the lung and second, the technical difficulties of interrogating neutrophil responses in mice, which has largely restricted basic murine research to specialized laboratories. To address these limitations, we have developed a suite of techniques for studying neutrophil effector functions specifically in the mouse lung. These include ex vivo assays for phagocytosis and NETosis using bronchoalveolar neutrophils and in situ evaluation of NETosis in a murine model of pneumonia. Throughout, we have prioritized technical ease and robust, quantitative readouts. We hope these assays will help to standardize research on lung neutrophils and improve accessibility to this burgeoning field.

"POMELO PROJECT" - a simple and low cost simulator for harvesting skin graft by plastic surgery residents.

BACKGROUND: Harvesting partial thickness skin grafts is an important technical skill the training plastic surgeon is required to hone. Historically accomplished via manual dermatome (Humby's knife) or the modern day electric dermatome. OBJECTIVE: Presenting a means of practicing the use of Humby's knife for novice surgeons. METHODS: 15 plastic surgeons comprising 8 seniors and 7 residents, in a single tertiary center participated. Each utilised a Humby knife to harvest 4 skin grafts from a Pomelo. The graft areas were measured via computerised image processing, comparing measures of graft harvest consistency across groups of surgeons. RESULTS: In the resident surgeon group, the average relative difference between exact graft area and encompassing area was 0.45, as compared with 0.15 in the Senior surgeon group, indicating a greater degree of inconsistency in graft harvest. Comparisons across groups yielded significant differences per each of the 4 grafts harvested (p <=0.005). LIMITATIONS: single center and small cohort (inherent to the sparsity of plastic surgeons), marginal statistical evidence. CONCLUSIONS: Citrus Maxima (Pomelo) is a useful substrate to instruct and practice the use of Humby knife effectively, allowing novice surgeons to practice the manual manoeuvres required therefore as well as increase confidence in its subsequent operative use.

Algorithm for Temple Reconstruction With Consideration of Anatomic and Defect Characteristics.

The temple is an intriguing region of the face with unique anatomic features, such as the temporal hairline, concave contour, and close proximity to vital structures like the frontal branch of the facial nerve. However, cancerous skin lesions can plague this sun-exposed region and, when excised, it can result in large and significant defects. Reconstruction in this area is a formidable challenge for surgeons, as it requires comprehensive knowledge of temple morphology and the use of creative techniques in order to minimize disruption of surrounding functional and aesthetic structures. In this study, we describe our experience with temple reconstruction in patients of varying defect size and depth. Based on these defect characteristics, anatomic and aesthetic principles of the temple, we propose a surgical algorithm for temple reconstruction to aid surgeons in achieving optimal results.

Is Being Left Handed an Advantage toward a Plastic Surgery Residency?

Left hand dominance is a minority trait historically regarded as disadvantageous for surgeons. Contemporary scientific literature and folklore have shed new light on left handedness as a "boutique trait" and possible marker of gifted and exceptional individuals. Our subjective impression that left handedness is prevalent in the unique field of plastic surgery raised questions regarding the scope and possible causality of this phenomenon. METHODS: One hundred eleven medical doctors in our medical center filled out a 13-item questionnaire regarding hand dominance, medical speciality, and various creative outlets or hobbies. RESULTS: Sixty-four percent of the participating plastic surgeons were left handed (significantly higher than the approximate 12% of the general population; P = 0.007). Many of the left-handed doctors admitted to practicing musical instruments and various arts, crafts, and other hobbies. CONCLUSIONS: Plastic surgery is a unique profession requiring astute minds capable of creative and "outside-the-box" thinking; traits we have learned in recent decades may be particularly keen in left-handed individuals, perhaps suggest a causal relationship to the conglomeration of a majority of left-handed plastic surgeons.

One-Step Triple-Layer Reconstruction of an Exposed Calvarium in a Patient With Radiated Tinea Capitis.

Full-thickness large scalp defects with underlying exposed calvarium pose a significant reconstructive challenge. Traditional reconstructive techniques are usually not an option in patients with irradiated scalp with thin skin and reduced laxity.Dermal substitutes-based reconstruction techniques have been described in recent years. A common approach is the staged methodology, with the initial application of skin substitute followed by a split-thickness skin graft few weeks later; however, this method involves a prolonged period of local wound management prior to skin grafting and is often associated with complications that interfere with wound healing.This report describes a single-stage triple-layer technique for the reconstruction of a large scalp defect with exposed bone in a patient with a history of radiation treatment, using 3 turnover pericranial flaps in conjunction with a Matriderm dermal substitute and split-thickness skin graft. This immediate multilayered reconstruction provides a long-lasting structural and aesthetic outcome, with minimal donor site morbidity and reduced complications.

Improving CNN Training using Disentanglement for Liver Lesion Classification in CT.

Training data is the key component in designing algorithms for medical image analysis and in many cases it is the main bottleneck in achieving good results. Recent progress in image generation has enabled the training of neural network based solutions using synthetic data. A key factor in the generation of new samples is controlling the important appearance features and potentially being able to generate a new sample of a specific class with different variants. In this work we suggest the synthesis of new data by mixing the class specified and unspecified representation of different factors in the training data which are separated using a disentanglement based scheme. Our experiments on liver lesion classification in CT show an average improvement of 7.4% in accuracy over the baseline training scheme.

Hierarchical Fine-Tuning for joint Liver Lesion Segmentation and Lesion Classification in CT.

We present an automatic method for joint liver lesion segmentation and classification using a hierarchical fine-tuning framework. Our dataset is small, containing 332 2-D CT examinations with lesion annotated into 3 lesion types: cysts, hemangiomas, and metastases. Using a cascaded U-net that performs segmentation and classification simultaneously, we trained a strong lesion segmentation model on the dataset of MICCAI 2017 Liver Tumor Segmentation (LiTS) Challenge. We used the trained weights to fine-tune a slightly modified model to obtain improved lesion segmentation and classification, on the smaller dataset. Since pre-training was done with similar data on a related task, we were able to learn more representative features (especially higher-level features in the U-Net's encoder), and improve pixel-wise classification results. We show an improvement of over 10% in Dice score and classification accuracy, compared to a baseline model. We further improve the classification performance by hierarchically freezing the encoder part of the network and achieve an improvement of over 15% in Dice score and classification accuracy. We compare our results with an existing method and show an improvement of 14% in the success rate and 12% in the classification accuracy.

Augmented Reality-Assisted Percutaneous Dilatational Tracheostomy in Critically Ill Patients With Chronic Respiratory Disease.

Percutaneous dilatational tracheostomy is a minimally invasive procedure performed for those who require prolonged mechanical ventilation. It is a procedure that is performed routinely at the bedside in the intensive care unit. Complications nonetheless still occur, and as a result, several technique modifications have been employed. At Loma Linda University Medical Center, we have implemented a novel technique using augmented reality during percutaneous dilatational tracheostomy placement in an attempt to minimize such complications. Using Brother's AiRScouter WD-200B head mounted display, the tracheostomy operator is able to focus on the surgical field without having to significantly break line of sight to view the traditional bronchoscopy monitor. Six cases have been treated with this procedure to date with good success and excellent user feedback. We aim to assess augmented reality-assisted percutaneous dilatational tracheostomy and determine its overall efficacy when compared to traditional percutaneous dilatational tracheostomy.

Improving Outcome in Immediate Alloplastic Breast Reconstruction, an Algorithm for Operative Decision Making.

Supplemental Digital Content is available in the text.

CT Image-based Decision Support System for Categorization of Liver Metastases Into Primary Cancer Sites: Initial Results.

RATIONALE AND OBJECTIVES: This study aimed to provide decision support for the human expert, to categorize liver metastases into their primary cancer sites. Currently, once a liver metastasis is detected, the process of finding the primary site is challenging, time-consuming, and requires multiple examinations. The proposed system can support the human expert in localizing the search for the cancer source by prioritizing the examinations to probable cancer sites. MATERIALS AND METHODS: The suggested method is a learning-based approach, using computed tomography (CT) data as the input source. Each metastasis is circumscribed by a radiologist in portal phase and in non-contrast CT images. Visual features are computed from these images, combined into feature vectors, and classified using support vector machine classification. A variety of different features were explored and tested. A leave-one-out cross-validation technique was conducted for classification evaluation. The methods were developed on a set of 50 lesion cases taken from 29 patients. RESULTS: Experiments were conducted on a separate set of 142 lesion cases taken from 71 patients with four different primary sites. Multiclass categorization results (four classes) achieved low accuracy results. However, the proposed system was found to provide promising results of 83% and 99% for top-2 and top-3 classification tasks, respectively. Moreover, when compared to the experts' ability to distinguish the different metastases, the system shows improved results. CONCLUSIONS: Automated systems, such as the one proposed, show promising new results and demonstrate new capabilities that, in the future, will be able to provide decision and treatment support for radiologists and oncologists, toward more efficient detection and treatment of cancer.

[DEMOGRAPHIC AND ANATOMIC CHARACTERISTICS AND SURGERY RESULTS IN CHILDREN WHO WERE TREATED IN SOROKA FOR CRANIOSYNOSTOSIS].

BACKGROUND: Craniosynostosis, the premature fusion of one or more of the cranial sutures, can occur as a part of a syndrome or as an isolated deformity. When not treated properly it may have major physical and social implications. STUDY HYPOTHESIS: We assumed that our center's results are similar to those reported in the literature, in terms of gender and anatomic characteristics, and different in terms of the number of syndromic cases. We also assume that only a few patients needed a second surgery and that this medical problem effects quality of life in term of cognitive impairment and aesthetic results. METHODS: A retrospective chart review was conducted of patients who were treated for craniosynostosis in Soroka University Medical Center between the years 1991-2005. RESULTS: A total of 63 patients were treated in Soroka during those years: 30 (47.6%) were females and 33 (50.8%) were males; 27 (42.9%) had coronal synostosis, 20 (31.8%) had sagital synostosis, 10 (15.8%) had metopic synostosis, 5 (7.9%) had lambdoid synostosis. A total of 5 (7.9%) cases were syndromic and the rest were isolated; 6 patients (9.5%) needed a second surgery for correction of the defect; 8 out of 30 patients (26.7%) 6 years or older at the present time suffer from attention deficit disorder. Parents' satisfaction from aesthetic results on a scale of 1-5 was 4.77 with SD of 0.504, while the doctors' score was 3.93 with SD 0.980 (p = 0.01). CONCLUSIONS: Craniosynostosis is a complex surgical problem, however with prompt treatment it may attain high levels of satisfaction among parents and patients. We found high rates 26.7% vs 10% (in the general population) of ADD in children affected by the disease.