19043 research outputs found
Sort by
Imaging and Characterization of Optical Emission From Ex Vivo Tissue During Conventional and UHDR PBS Proton Therapy
No full textObjective. Imaging of optical photons emitted from tissue during radiotherapy is a promising technique for real-time visualization of treatment delivery, offering applications in dose verification, treatment monitoring, and retrospective treatment plan comparison. This research aims to explore the feasibility of intensified imaging of tissue luminescence during proton therapy (PT), under both conventional and ultra-high dose rate (UHDR) conditions. Approach. Conventional and UHDR pencil beam scanning (PBS) PT irradiation of fresh ex vivo porcine tissue and tissue-mimicking plastic phantom was imaged using intensified complementary metal-oxide-semiconductor(CMOS) cameras. The optical emission from tissue was characterized during conventional irradiation using both blue and red-sensitive intensifiers to ensure adequate spectral coverage. Spectral characterization was performed using bandpass filters between the lens and sensor. Imaging of conventional proton fields (240 MeV, 10 nA) was performed at 100 Hz frame rate, while UHDR PBS proton delivery (250 MeV, 99 nA) was recorded at 1 kHz frame rate. Dependence of optical emission yield on proton energy was studied using an optical tissue-mimicking plastic phantom and a range shifter. Finally, we demonstrated fast beam tracking capability of fast camera towards in vivo monitoring of FLASH PT. Main results. Under conventional treatment dose rates optical emission was imaged with single spot resolution. Spot profiles were found to agree with the treatment planning system calculation within \u3e90% for all spectral bands and spot intensity was found to vary with spectral filtration. The resultant polychromatic emission presented a maximum intensity at 650 nm and decreasing signal at lower wavelengths, which is consistent with expected attenuation patterns of high fat and muscle tissue. For UHDR beam imaging, optical yield increased with higher proton energy. Imaging at 1 kHz allowed continuous monitoring of delivery during porcine tissue irradiation, with clear identification of individual dwell positions. The number of dwell positions matched the treatment plan in total and per row showing adequate temporal capability of iCMOS imaging. Significance. For the first time, this study characterizes optical emission from tissue during PT and demonstrates our capability of fast optical tracking of pencil proton beam on the tissue anatomy in both conventional and UHDR setting. Similar to the Cherenkov imaging in radiotherapy, this imaging modality could enable a seamless, independent validation of PT treatments
A Cross-Sectional Analysis of Insurance Acceptance Among Mohs Micrographic Surgeons in New York City
No full textEmbracing the Challenges of Neonatal and Paediatric Pulmonary Hypertension
No full textPaediatric pulmonary arterial hypertension (PAH) shares common features with adult disease, but is associated with several additional disorders and challenges that require unique approaches. This article discusses recent advances, ongoing challenges and distinct approaches for caring for infants and children with PAH, as presented by the paediatric task force of the 7th World Symposium on Pulmonary Hypertension. We provide updates on diagnosing, classifying, risk-stratifying and treating paediatric pulmonary hypertension (PH) and identify critical knowledge gaps. An updated risk stratification tool and treatment algorithm is provided, now also including strategies for patients with associated cardiopulmonary conditions. Treatment of paediatric PH continues to be hindered by the lack of randomised controlled clinical trials. The challenging management of children failing targeted PAH therapy is discussed, including balloon atrial septostomy, lung transplantation and pulmonary-to-systemic shunt (Potts). A novel strategy using a multimodal approach for the management of PAH associated with congenital heart diseases with borderline pulmonary vascular resistance is included. Advances in diagnosing neonatal PH, especially signs and interpretation of PH by echocardiography, are highlighted. A team approach to the rapidly changing physiology of neonatal PH is emphasised. Challenges in drug approval are discussed, particularly the challenges of designing accurate paediatric clinical trials with age-appropriate end-points and adequate enrolment
An Explainable Machine Learning Model for Prediction of High-Risk Nonalcoholic Steatohepatitis
No full textEarly identification of high-risk metabolic dysfunction-associated steatohepatitis (MASH) can offer patients access to novel therapeutic options and potentially decrease the risk of progression to cirrhosis. This study aimed to develop an explainable machine learning model for high-risk MASH prediction and compare its performance with well-established biomarkers. Data were derived from the National Health and Nutrition Examination Surveys (NHANES) 2017-March 2020, which included a total of 5281 adults with valid elastography measurements. We used a FAST score ≥ 0.35, calculated using liver stiffness measurement and controlled attenuation parameter values and aspartate aminotransferase levels, to identify individuals with high-risk MASH. We developed an ensemble-based machine learning XGBoost model to detect high-risk MASH and explored the model’s interpretability using an explainable artificial intelligence SHAP method. The prevalence of high-risk MASH was 6.9%. Our XGBoost model achieved a high level of sensitivity (0.82), specificity (0.91), accuracy (0.90), and AUC (0.95) for identifying high-risk MASH. Our model demonstrated a superior ability to predict high-risk MASH vs. FIB-4, APRI, BARD, and MASLD fibrosis scores (AUC of 0.95 vs. 0.50, 0.50, 0.49 and 0.50, respectively). To explain the high performance of our model, we found that the top 5 predictors of high-risk MASH were ALT, GGT, platelet count, waist circumference, and age. We used an explainable ML approach to develop a clinically applicable model that outperforms commonly used clinical risk indices and could increase the identification of high-risk MASH patients in resource-limited settings
Expanding the Differential Diagnosis of the Painful Nail: A Case of an Onychopapilloma With Neuroma
No full textIntroduction: Onychopapilloma most commonly presents as longitudinal erythronychia, but diagnosis may be challenging in some cases due to varied clinical presentations. Most patients with onychopapillomas do not report associated pain but instead more commonly report functional interference. Case Report: We present a case of a 74-year-old female with a 5-year history of splitting and lifting of the right thumbnail, accompanied by nail sensitivity and intermittent painful throbbing. Clinical examination was significant for a less than 1 mm red line with distal onycholysis. Love s test and a cold test performed with ice pack were negative. X-ray of the right thumb was negative for erosion or exostosis. Nail biopsy was performed, and dermatopathology was consistent with onychopapilloma with a concomitant traumatic neuroma. Conclusion: We report a case of onychopapilloma with a concomitant traumatic neuroma. Subungual neuromas are extremely rare and have not previously been associated with onychopapilloma. Our case supports the expansion of the differential diagnosis for a painful nail and demonstrates the importance of diagnostic confirmation with biopsy and histopathology
Invasive Squamous Cell Carcinoma Arising From a Cystic Brow Mass
No full textAn 82-year-old woman presented with a 6-month history of an enlarging brow mass that developed after trauma. Clinical and MRI appearance of the lesion appeared consistent with epidermal inclusion cyst. However, excisional biopsy demonstrated invasive squamous cell carcinoma, which recurred 6 weeks later and required repeat surgical excision. To our knowledge, this represents the first case of squamous cell carcinoma arising from a posttraumatic epidermal inclusion cyst
Identification of a Novel Homozygous Missense Mutation in the Phospholipase C, Delta-1 Gene Associated With Leukonychia in a Middle Eastern Patient
No full textCorrection: Do Peri‑Operative Parathyroid Hormone (PTH) Analogues Improve Bone Density and Decrease Mechanical Complications in Spinal Deformity Correction?—A Minimum 2‑Year Radiological Study Measuring Hounsfield Units (European Spine Journal, (2023), 32, 10, (3651-3658), 10.1007/S00586-023-07859-2)
No full textA co-author name has been missed out in the original publication. The complete correct name is given below. Bardia Khandehroo The original article has been corrected
Platelet Distribution Width (PDW) as a Significant Correlate of COVID-19 Infection Severity and Mortality
No full textSARS-CoV-2 infection may cause a wide spectrum of symptoms, from asymptomatic, to mild respiratory symptoms and life-threatening sepsis. Among the clinical laboratory biomarkers analyzed during COVID-19 pandemic, platelet indices have raised great interest, due to the critical involvement of platelets in COVID-19-related thromboinflammation. Through an electronic literature search on MEDLINE, CINAHL, PubMed, EMBASE, Web of Science, and preprint servers we performed and updated a systematic review aimed at providing a detailed analysis of studies addressing the potential clinical utility of platelet distribution width, platelet distribution width (PDW), in laboratory medicine, exploring the possible association between increased PDW levels, disease severity, and mortality in COVID-19. Our systematic review revealed a wide heterogeneity of COVID-19 cohorts examined and a lack of homogenous expression of platelet indices. We found that 75 % of studies reported significantly elevated PDW values in COVID-19 infected cohorts compared to healthy/non-COVID-19 controls, and 40 % of studies reported that patients with severe COVID-19 showed increased PDW values than those with less-than-severe illness. Interestingly, 71.4 % of studies demonstrated significant increased PDW values in non survivors vs. survivors. Overall, these results suggest that platelets are critically involved as major players in the process of immunothrombosis in COVID-19, and platelet reactivity and morphofunctional alterations are mirrored by PDW, as indicator of platelet heterogeneity. Our results confirm that the use of PDW as prognostic biomarkers of COVID-19 sepsis still remains debated due to the limited number of studies to draw a conclusion, but new opportunities to investigate the crucial role of platelets in thrombo-inflammation are warranted
