A Survey on Intelligent Screening for Diabetic Retinopathy

Diabetic retinopathy (DR) is one of the leading causes of vision loss and can be effectively avoided by screening, early diagnosis and treatment. In order to increase the universality and efficiency of DR screening, many efforts have been invested in developing intelligent screening, and there have been great advances. In this paper, we survey DR screening from four perspectives: 1) public color fundus image datasets of DR; 2) DR classification and related lesion-extraction approaches; 3) existing computer-aided systems for DR screening; and 4) existing issues, challenges, and research trends. Our goal is to provide insights for future research directions on DR intelligent screening.     

Diagnosis and treatment of the invasive extension of bacteria (cellulitis) from chronic wounds utilising point‐of‐care fluorescence imaging

Early diagnosis of wound‐related cellulitis is challenging as many classical signs and symptoms of infection (erythema, pain, tenderness, or fever) may be absent. In addition, other conditions (ie, chronic stasis dermatitis) may present with similar clinical findings. Point‐of‐care fluorescence imaging detects elevated bacterial burden in and around wounds with high sensitivity. This prospective observational study examined the impact of incorporating fluorescence imaging into standard care for diagnosis and management of wound‐related cellulitis. Two hundred thirty‐six patients visiting an outpatient wound care centre between January 2020 and April 2021 were included in this study. Patients underwent routine fluorescence scans for bacteria (range: 1‐48 scans/patient). Wound‐related cellulitis was diagnosed in 6.4% (15/236) of patients. In these patients, fluorescence scans showed an irregular pattern of red (bacterial) fluorescence extending beyond the wound bed and periwound that could not be removed through cleansing or debridement, indicating the invasive extension of bacteria (wound‐related cellulitis). Point‐of‐care identification facilitated rapid initiation of treatments (source control and antibiotics, when warranted) that resolved the fluorescence. No patients had worsening of cellulitis requiring intravenous antibiotics and/or hospitalisation. These findings demonstrate the utility of point‐of‐care fluorescence imaging for efficient detection and proactive, targeted management of wound‐related cellulitis.     

Mechanical pulmonic valve thrombosis: expanding role of cardiac CT and multimodality imaging

We report a case of a 44-year-old man with a clinical history of Tetralogy of Fallot status post staged surgical correction with mechanical pulmonic valve replacement who presented with progressive exertional dyspnea in the setting of non-compliance with anticoagulation. In the context of this suggestive clinical presentation, the diagnosis of mechanical pulmonic valve thrombosis (MPVT) was made possible via multimodality imaging, including transthoracic echocardiogram and cardiac computed tomography angiography. Due to the uncommon nature of the condition, the patient was treated with systemic thrombolysis and anticoagulation using evidence-based guidelines, largely extrapolated from left-sided mechanical valve thrombosis. Our case underscores the importance of anticoagulation in MPVT and recognizing the features of MPVT on clinical history, physical examination, and multimodality imaging. It is essential to understand the pivotal role of multimodality imaging in the assessment of MPVT and realize the limitations of available data regarding the management of MPVT in the current era.     

Development and evaluation of time‐resolved fluorescent immunochromatographic assay for quantitative detection of SARS‐CoV‐2 spike antigen

BackgroundThe spread of COVID‐19 worldwide caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has necessitated efficient, sensitive diagnostic methods to identify infected people. We report on the development of a rapid 15‐minute time‐resolved fluorescent (TRF) lateral flow immunochromatographic assay for the quantitative detection of the SARS‐CoV‐2 spike protein receptor‐binding domain (S1‐RBD).ObjectivesOur objective was to develop an efficient method of detecting SARS‐CoV‐2 within 15 min of sample collection.MethodsWe constructed and evaluated a portable, disposable lateral flow device, which detected the S1‐RBD protein directly in nasopharyngeal swab samples. The device emits a fluorescent signal in the presence of S1‐RBD, which can be captured by an automated TRF instrument.ResultsThe TRF lateral flow assay signal was linear from 0 to 20 ng/ml and demonstrated high accuracy and reproducibility. When evaluated with clinical nasopharyngeal swabs, the assay was performed at >80% sensitivity, >84% specificity, and > 82% accuracy for detection of the S1‐RBD antigen.ConclusionThe new S1‐RBD antigen test is a rapid (15 min), sensitive, and specific assay that requires minimal sample preparation. Critically, the assay correlated closely with PCR‐based methodology in nasopharyngeal swab samples, showing that the detected S1‐RBD antigen levels correlate with SARS‐CoV‐2 virus load. Therefore, the new TRF lateral flow test for S1‐RBD has potential application in point‐of‐care settings.     

Chest pain in the emergency department: From score to core—A prospective clinical study

High-sensitivity troponin assay brought new challenges as we detect elevated concentration in many other diseases, and it became difficult to distinguish the real cause of this elevation. In this notion, diagnosis of acute coronary syndrome (ACS) remains a challenge in emergency department (ED).We aim to examine different approaches for rule-in and rule-out of ACS using risk scores, copeptin, and coronary computed tomography angiography (CCTA).A prospective observational study was designed to evaluate chest pain patients. Consecutive adult patients admitted to the ED with a chief complaint of chest pain due to any cause were included.All patients were followed-up for 6 months after discharge for major adverse cardiovascular events and readmissions. Admission data, ED processes, and diagnoses were analyzed.One hundred forty-six patients were included, average age was 63 ± 13.4 years, and 95 (65.1%) were male. Global Registry of Acute Coronary Events (GRACE) and History, ECG, Age, Risk factors, Troponin (HEART) scores showed good prognostic abilities, but HEART combination with copeptin improves diagnoses of myocardial infarction (area under the curve [AUC] 0.764 vs AUC 0.864 P = .0008). Patients with elevated copeptin were older, had higher risk scores, and were more likely to be admitted to hospital and diagnosed with ACS in ED. For copeptin, AUC was 0.715 (95% confidence interval 0.629–0.803), and for combination with troponin, AUC of 0.770 (0.703–0.855) did not improve rule-in of myocardial infarction. High-sensitivity troponin I assay alongside prior stroke, history of carotid stenosis, dyslipidemia, use of diuretics, and electrocardiogram changes (left bundle branch block or ST depression) are good predictors of myocardial infarction (χ² = 52.29, AUC = 0.875 [0.813–0.937], P < .001). The regression analysis showed that combination of copeptin and CCTA without significant stenosis can be used for ACS rule-out (χ² = 26.36, P < .001, AUC = 0.772 [0.681–0.863], negative predictive value of 96.25%).For rule-in of ACS, practitioner should consider not only scores for risk stratification but carefully analyze medical history and nonspecific electrocardiogram changes and even with normal troponin results, we strongly suggest thorough evaluation in chest pain unit. For rule-out of ACS combination of copeptin and CCTA holds great potential.     

布加综合征的多层螺旋CT诊断

目的 探讨多层螺旋CT(multislice spiral CT, MSCT)在布加综合征(Budd-Chiari syndrome, BCS)中的诊断价值.方法 回顾性分析28例经DSA或手术证实的布加综合征MSCT影像特点.结果 BCS的MSCT特点为:①CT平扫形态学改变:肝脏不规则增大15例,弥漫增大10例,未见明显改变3例;②强化特征:花斑状强化型11例,周边强化型6例,中央强化型8例,不规则强化3例;③CTA准确显示阻塞的部位及侧支循环血管:肝静脉闭塞3例;下腔静脉狭窄闭塞25例,其中7例伴肝静脉闭塞;显示肝外侧支循环16例,肝内侧支循环2例,肝内外均有侧支循环7例,3例无侧支循环血管.结论 MSCT能准确直观反映布加综合征阻塞的性质、部位、范围、侧支血管及其与周围器官的空间关系,能从形态及功能上反映肝脏损害程度.     

非小细胞肺癌ALK基因重排检测

目的 通过荧光原位杂交(FISH)方法检测非小细胞肺癌(NSCLC)患者间变性淋巴瘤激酶(ALK)基因重排.方法 根据ALK断裂重排方式及特点,设计并制备红/绿双色荧光探针.以人外周血培养细胞为检测对象评价ALK融合基因检测探针的敏感性和特异性,以NSCLC石蜡组织样本为对象进行ALK基因重排检测以评价探针的性能.结果 本研究制备的荧光探针在EB病毒(EBV)转化的人淋巴细胞检测中的特异性和敏感性均可达到100％.在对2例NSCLC患者石蜡包埋组织样本检测中,检测阴性、阳性各1例,检测结果与免疫组织化学检测结果一致.结论 本研究中制备的双色荧光探针可用于NSCLC ALK基因重排的检测.