Ultrasound Scanning Competencies in Midwifery Education in Zambia: Findings from a Desk Review and Needs Assessment

Introduction: Ultrasound is an essential component of antenatal care. Midwives provide most of the antenatal care but they do not perform ultrasound as it has been beyond their scope of practice. This leaves many women in Low and Middle-Income Countries without access to ultrasound scanning. The aim of this study was to identify competencies in ultrasound scanning in midwifery education. Methods: A desk review and needs assessment were conducted between July and October 2023. Articles and curricula on the internet, Google scholar and PubMed were searched for content on ultrasound scanning competencies. A Google form consisting of 20 questions was administered via email and WhatsApp to 135 participants. Descriptive statistics were used to analyse data. Results: The desk review showed that it is feasible to train midwives in ultrasound scanning. The training programs for midwives in obstetric ultrasound were conducted for 1 week to 3 months with most of them running for 4 weeks. Content included introduction to general principles of ultrasound, physics, basic knowledge in embryology, obstetrics, anatomy, measuring foetal biometry, estimating amniotic fluid and gestational age. Experts like sonographers trained midwives. Theory and hands on were the teaching methods used. Written and practical assessments were conducted. Needs assessment revealed that majority of participants 71 (53%) knew about basic ultrasound training for midwives. All participants (100%) said it is necessary to train midwives in basic ultrasound scan in Zambia. Some content should include, anatomy, measuring foetal biometry, assessing amniotic fluid level, and gestational age determination. Most participants 91 (67%) suggested that the appropriate duration of training is 4 - 6 weeks. Conclusion: Empowering every midwife with ultrasound scanning skills will enable early detection of any abnormality among pregnant women and prompt intervention to save lives.

Progress of research in the application of ultrasound technology for the treatment of Alzheimer’s disease

Alzheimer’s disease is a common neurodegenerative disorder defined by decreased reasoning abilities,memory loss,and cognitive deterioration.The presence of the blood-brain barrier presents a major obstacle to the development of effective drug therapies for Alzheimer’s disease.The use of ultrasound as a novel physical modulation approach has garnered widespread attention in recent years.As a safe and feasible therapeutic and drug-delivery method,ultrasound has shown promise in improving cognitive deficits.This article provides a summary of the application of ultrasound technology for treating Alzheimer’s disease over the past 5 years,including standalone ultrasound treatment,ultrasound combined with microbubbles or drug therapy,and magnetic resonance imaging-guided focused ultrasound therapy.Emphasis is placed on the benefits of introducing these treatment methods and their potential mechanisms.We found that several ultrasound methods can open the blood-brain barrier and effectively alleviate amyloid-βplaque deposition.We believe that ultrasound is an effective therapy for Alzheimer’s disease,and this review provides a theoretical basis for future ultrasound treatment methods.

B-scan ultrasound and cytology of the vitreous in primary central nervous system lymphoma with vitreoretinal involvement

AIM: To evaluate the diagnostic value of B-scan ultrasound and explore the cytological characteristics of patients with vitreoretinal lymphoma(VRL) and primary central nervous system lymphoma(PCNSL).METHODS: The clinical data and pathologic specimens from patients with VRL diagnosed at the North Huashan Hospital from 2016 to 2017 were retrospectively reviewed. The patients were diagnosed by slit lamp ophthalmoscopy, B-scan ultrasound, cytology of the vitreous, which was obtained by vitrectomy, and cytokine measurements of interleukin(IL)-10 and IL-6.RESULTS: Twenty-six eyes(19.4%) out of 134 eyes of 67 patients(47 men and 20 women) with PCNSL were diagnosed with VRL by B-scan ultrasound, and 14 eyes(10.4%) were diagnosed by slit lamp ophthalmoscopy. Twenty-four eyes(17.9%) of 17 patients were confirmed as having VRL with cytology. No difference in the association between intracranial lesion location and ocular involvement was found. VRL patients had higher levels of vitreous IL-10 and IL-10/IL-6 when compared with macular hole cases, but the difference was not statistically significant.CONCLUSION: A total of 25.4% of the PCNSL patients had VRL, B-scan ultrasound examination had characteristic features and is recommended over slit lamp ophthalmoscopy for the screening diagnosis of PCNSL with intraocular involvement. Moreover, the cytological and immunohistochemical analyses performed after 25-gauge diagnostic vitrectomy were accurate diagnostic techniques.

Development of a High-frequency Ultrasound System for High-speed Image Scanning

High-frequency image technique has been widely applied in medical diagnosis recently. For high voltage protection, high speed stage and trigger control circuitry are difficult to implement a high-frequency ultrasound imaging system. In this study, we utilized a linear servo with high noise tolerance and a novel multi-depth expression method to overcome those issues in developed high-speed image system. B-mode image of the chicken phantom by 25 MHz transducer shows the resolution of lateral and axial resolutions are up to 123 μm and 59 μm respectively. In addition, the experiment demonstrates that the axial resolution and depth of field (DOF) can be improved by time gain compensation(TGC) and multi-depth method. The results indicate that the proposed system could achieve over 24 fps for 1 mm scan distance and 100 lines per frame. In the future, the developed system is potential for other clinical applications such as ophthalmology and dermatology.

Assessing gestational age of babies: Performance of obstetric ultrasound scan compared to that from the combination of Naegle’s rule and Dubowitz score in the 21st century

Background: Some researchers have suggested that when Naegle’s rule (NR) and Dubowitz score (DS) are combined, it could out-perform obstetric ultrasound scan (USS). Others still believe that obstetric USS alone is still effective relative to the combination of NR rule and DS in assessing the gestational age (GA) of babies. Objectives: To determine and compare the GA of babies using obstetric USS, NR and DS;and to provide relevant public health information on obstetric USS in the 21st century. Methods: Subjects were selected using systematic random sampling and the GA of babies was determined using obstetric USS, NR, and DS. Statistical package for social science (SPSS) statistical software version 16, Illinois, Chicago USA was used for all data analysis. Results: Eightyfive mother-baby pairs were studied. Forty-four babies (52%) were males and 41 (48%) females. Sixty four (75%) were term with a mean (SD) BW of 3.02 (0.59) at 95%CI (2.89 -?3.14) kg. The overall mean GA of the babies was 38.49 (2.89) at 95%CI (38.14 -?38.85) weeks. The mean GA using obstetric USS, NR and DS were 38.52 (1.98) at 95%CI (38.14 -?38.99), 38.09 (4.13) at 95%CI (37.20-?38.99) and 38.82 (2.02) at 95%CI (38.39 -?39.26), but comparison of these means was not significant (p = 0.256). Combined mean GA by NR and DS was 38.46 (3.26) at 95%CI (37.96 -?38.95). Comparing this mean with mean GA obtained by obstetric USS was also not significant (p = 0.885). Conclusion: The GA assessments by Obstetric USS, NR and DS were all reliable, and Obstetric USS performed effectively relative to combined NR and DS.

Fazari’s Sign in Ultrasound Scan of Morbid Adherent Placenta/Placenta Accreta Spectrum (MAP/PAS) and Fazari’s Triad during (MAP/PAS) Surgery

Morbid Adherent Placenta (MAP)/Placenta Accreta Spectrum (PAS) is a serious diagnosis which has a risk of complications. Ultrasound scan helps in early diagnosis and has great value in further confirmation and follow up. Observed new clinical sign and associated clinical triad are discussed here.

A Flexible and High Speed Digital Scan Converter for High Frequency Ultrasound Imaging

This paper presents a flexible and high speed digital scan converter (DSC) with the ability to handle high frequency ultrasound imaging in real-time. The characteristics in imaging system such as focus length of transducer, the swing radius and sampling length etc. could be changed easily in compliance with the researcher's application based on this flexible digital scan converter. Linear interpolation is employed to achieve the coordinate transformations algorithm. Custom-built software is programmed to preliminarily handle the algorithm according to different ultrasound imaging applications. High performance FPGA will implement high speed interpolation calculation based on the preliminary data which are stored in the DDR2 SDRAM from the software. 64 bit 66 MHz PCI is employed to accomplish high speed data transmission. Experiment has shown that more than 500 frame rate could be achieved based on this high speed digital scan converter. The designed flexible and high speed digital scan converter could be used in current FPGA based high frequency ultrasound imaging system.

检测声学成像原理与技术综述

声学成像是现代检测领域当中的一门常用的技术。它利用超声波强大的穿透能力获取反映被测区域内部结构和物理性质的声学信息,能够提供直观的结构二维或三维图像,从而为医学诊断、工业无损检测和水下探测等方面的研究和应用提供依据。该文从成像结果的维度出发,通过将现有的检测声学成像方法划分二维厚度截面成像、二维水平截面成像和三维成像三种类型,对包含扫描成像、相控阵成像、合成孔径聚焦成像和超声层析成像在内的各方法的原理和技术特点进行了综述,阐述了这些方法的具体实施过程,并归纳了其优缺点。最后综合分析了影响这些方法准确性、实时性和经济性的主要因素,并给出了相应的应对策略。

AL-Scan、IOL-Master和A超测量白内障患者眼轴长度的准确性和一致性分析

目的比较AL-Scan、IOL-Master和A超测量白内障患者眼轴长度(axial length,AL)的准确性和一致性。方法选取年龄相关性白内障患者95例(142眼),术前分别应用AL-Scan、IOL-Master和A超进行AL测量。根据AL将患者分为AL≤22 mm(20眼)、22mm<AL≤26 mm(98眼)和AL>26 mm(24眼)3组。应用方差分析对3种方法测量的结果进行比较,应用Bland-Altman法对其一致性进行分析。结果 AL≤22 mm组AL-Scan、IOL-Master和A超测得AL结果分别为(21.53±0.30)mm、(21.54±0.29)mm及(21.51±0.30)mm,差异无统计学意义(P>0.05);22 mm<AL≤26 mm组分别为(23.68±0.76)mm、(23.71±0.77)mm及(23.65±0.75)mm,差异无统计学意义(P>0.05);AL>26 mm组分别为(28.46±1.60)mm、(28.50±1.62)mm及(28.40±1.63)mm,差异无统计学意义(P>0.05)。AL测量的95%一致性界限范围是0.20 mm(AL-Scan和IOL-Master)、1.12 mm(IOLMaster和A超)和1.12 mm(AL-Scan和A超)。结论 AL-Scan、IOL-Master和A超测量白内障患者AL同样准确,但AL-Scan与IOL-Master之间具有良好的一致性。

电工纯铁与不锈钢扩散焊接头自动超声C扫检测技术研究

由扩散焊焊接而成线圈骨架零件(电工纯铁+不锈钢)因具有焊缝界面平整,尺寸精度高,焊接质量优良等优势已经在航空航天产品上得到了广泛应用。而扩散焊作为一种精密焊接成形技术受焊接工艺、表面状态等影响,其焊缝界面容易出现一些常规检查难以发现的微小缺陷,若不采取有效的检测手段发现这些缺陷,在后续产品的使用过程中将有可能出现严重后果。在不改变现有线圈骨架零件焊接结构的基础上,采用自行研制的水浸式超声C扫描检测系统,通过设计对比试块,调整合适的聚焦探头,扫描步进,成功实现了扩散焊缝接头扫查成像。在此基础上,结合产品使用工况、拉伸及金相对比试验和相关技术文献制定了适用于线圈骨架扩散焊缝的超声C扫判定准则,实现了产品的无损检测,对控制焊缝质量起到了重要作用。

Evaluation of immersion 20 MHz B-scan ultrasonography in observing lens in the alkali burn eyes

·AIM: To evaluate the accuracy of 20 MHz immersion Bscan ultrasonography in observing lens and to investigate the value of this noninvasive preoperative diagnosis method in alkali burn eyes.·METHODS: It was a comparative study. Fifty-six cases(56 eyes) of alkali burn eyes were examined by ultrasound biomicroscopy(UBM) and immersion 20 MHz B-scan ultrasonography from June 2011 to April 2013,the images were analyzed, and the ultrasonographic diagnosis compared with the operation results.·RESULTS: In 56 alkali burn eyes examined by UBM, the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; the anterior lens capsule surface or/and the front lens could be detected in 18 eyes, and lens opacification in 3 eyes of them; suspected abnormal lens were detected in the other 20 eyes. In all the same eyes examined by immersion 20 MHz B-scan ultrasonography,the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; 24 abnormal lens(opacity, lens expansion, shrinkage) and 14 normal lens were found.Compared with the intraoperative findings, the diagnostic accordance rate of the immersion 20 MHz B-scan appearance of lens was 100%(56/56), which was significantly higher than examined by UBM 57.14%(32/56)(χ2=30.55, P =0.0000).·CONCLUSION: Immersion 20 MHz B-scan ultrasonography can observe the lens accurately in alkali burn eyes. It has important clinical value to combine with UBM in eyes of alkali burn.

AL-Scan与A型超声测量老年性白内障患者眼轴长度与前房深度的对比研究

目的比较AL-Scan与A型超声测量的眼轴长度(AL)及前房深度(ACD)的结果,验证AL-Scan的准确性及其临床应用价值。方法对白内障患者依次行AL-Scan与A型超声测量AL与ACD,比较两者的差异,数据进行统计分析。结果 AL-Scan测量的AL为(24.55±0.85)mm,A型超声测量的AL为(24.52±0.89)mm,两者的差异无统计学意义(t=0.463,P>0.05)。AL-Scan测量的ACD为(2.67±0.49 mm),A型超声测量的ACD为(2.61±0.53)mm,两者的差异无统计学意义(t=0.753,P>0.05)。结论 AL-Scan是一种在临床应用中准确性较高的生物学测量仪器,可用于眼轴及前房深度的测量。

IOL Master和A-scan在白内障合并黄斑病变中的应用比较

目的:比较光学相干生物测量仪(IOL Master)和A型超声测量(A-scan)在白内障合并黄斑病变眼轴测量和人工晶体测算的准确性及术后屈光状态的评价。方法:选取白内障合并黄斑病变需行超声乳化吸出并人工晶体植入术患者38例(46只眼),分别于术前和术后3个月检查术眼的视力并比较;术前采用光学相干断层扫描(OCT)检查术眼视网膜中央厚度(CRT);术前分别用IOL Master和A-scan测量术眼的眼轴长度(AL),根据AL选择人工晶体计算公式SRK-T或Haigis公式确定植入人工晶体(IOL)的度数、目标屈光度及预留的屈光度数并比较;采用Bland-Altman法分析2种测量方法的一致性,采用Pearson相关分析2种方法AL差值与CRT的相关性;比较2种测量方法预留屈光度数、术后3个月验光的绝对屈光误差(AE)及屈光漂移类型的差异。结果:患者术眼术后3个月裸眼视力较术前提高(P<0.05);Bland-Altman分析结果显示,2种测量方法AL差值的95%医学参考范围为-0.77~0.89 mm,其中最大差值的绝对值为0.45 mm;2种测量方法AL的差异无统计学意义(Z=-1.778,P=0.075),且AL的差值与CRT无相关性(r=0.087,P=0.564);IOL Master方法术后3个月AE值较A-scan更接近于0 D(P<0.001);2种测量方法术后3个月屈光漂移均以近视漂移为主,且近视漂移检出和AE介于0.00~1.00 D的比例均表现为测量方法IOL Master>A-scan(P<0.01)。结论:IOL Master和A-scan在测量白内障合并黄斑病变患者的AL上一致性好,与CRT无相关性;术后2种测量方法的屈光漂移均表现为近视漂移为主,且IOL Master准确性优于A-scan。

Ultrasound Diagnosis of Primary Epiploic Appendagitis: A Case Report

A rare differential diagnosis for severe abdominal pain is acute epiploic appendagitis. Its symptoms resemble those of acute diverticulitis, acute appendicitis, or omental infarction quite a bit. The primary imaging method used for diagnosis is computed tomography (CT). We are describing the case of a 27-year-old guy who underwent an abdominal ultrasonography after complaining of severe left lower quadrant abdominal pain. It identified an oval and non-compressible hyperechoic mass in the left iliac fossa. The mass was surrounded by a hypoechoic rim and there was no color Doppler signal. In the absence of CT, radiologists must be able to diagnose acute epiploic appendagitis on ultrasound in order to avoid unnecessary hospital admission, pricey laboratory tests, antibiotic treatment, and unnecessary surgery. In this instance, the patient was spared from ionization exposure from a potential CT scan and other invasive treatments including surgery with associated costs because of the reliable ultrasound diagnosis of epiploic appendagitis. After receiving conservative medical treatment, the patient was placed under surveillance and then discharged.

Accuracy of crescent sign on ocular ultrasound in diagnosing papilledema

AIM To study the usefulness of orbital ultrasonography in the diagnosis of papilledema.METHODS Fifty patients who were referred to the neurophthalmology clinic and clinically suspected to have papilledema were selected. Thorough, clinical examination with slitlamp biomicroscopy and visual acuity assessment was done. These patients underwent ultrasonography to demonstrate the crescent sign. The patients were further evaluated with the neurologist and magnetic resonance imaging(MRI) thus confirming the diagnosis of papilledema. The results of our ultrasonographic evaluation were correlated with final diagnosis after thorough clinical evaluation, imaging and the neurologist's opinion.RESULTS Out of 50 patients diagnosed having papilledema on MRI, 46(92%) showed crescent sign on B scan ultrasonography. Headache was most common presenting complaint in 47(94%) and idiopathic intracranial hypertension was most common underlying cause of papilledema in 30(60%) cases.CONCLUSION"Crescent sign" seen on ultrasonography is a sensitive tool for diagnosis of papilledema. It is cost effective, less cumbersome and effective tool to differentiatebetween papilledema and pseudo papilledema before subjecting the patients to costly investigations like MRI. A positive crescent sign should always be followed by MRI to find out the cause of papilledema.

The ultrasound diagnosis of fetal gastric teratoma

Objective: The aim of the study was to discuss the value of ultrasound examination in the diagnosis of fetal gastric teratoma. Methods: We retrospectively analyzed 2 cases with fetal gastric teratoma in our hospital (Department of Gynecology and Obstetrics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China). It involved clinical, ultrasonic, X-ray, CT and MRI, biochemical, pathological, karyotype and immunohistochemical data. Results: There both were hybrid echo masses in the abdominal of the fetus with the sonography and the ultrasound features which mostly like the teratomas. Two cases were dead after induced abortion. The pathological results of the mass were gastric immature teratoma in one, and stomach mature teratoma in another. Conclusion: Fetal gastric teratoma is rarely seen and easily be misdiagnosed in clinic. The diagnosis depends finally on pathological examination. Ultrasound scan as the easy and direct method is helpful to clew the diagnosis of fetal gastric teratoma.

Diagnostic Ultrasound and Pars Plana Vitrectomy in Endophthalmitis

Purpose: To compare the results by B-scan ultrasonography and findings in pars plana vitrectomy, and assess the diagnostic value of B-scan ultrasonography in endophthalmitis.Methods: Thirty eyes of 30 subjects diagnosed as endophthalmitis were selected, who undergone preoperative B-scan ultrasonography. The result of pars plana vitrectomy was recorded. The above two results were compared.Results: On the evaluation of vitreous and retinal states in the patients with endophthal-mitis, the sensitivity of ultrasound was 90%～100%, and the specificity was 79%～100%. Poorer preoperative visual acuity was related with retinal detachment and retinal dissolution. The preoperative visual acuity in eyes with local vitreous opacity was better than with diffuse vitreous opacity.Conclusion: Comparison of the results of B-scan ultrasonography and the findings in pars plana vitrectomy showed B-scan ultrasonography is highly sensitive,specific, and is very helpful in the evaluation of endophthalmitis. B-scan ultrasonography can not only supply much information in the diagnosis of endophthalmitis but also inspect its trends and changes, which is helpful in the selection of treatment and planning the time of surgery.

Additional Imaging Following a Negative Sestamibi Scan in Primary Hyperparathyroidism

Background: The objective of this study was to assess the additional yield of US and CT following a “negative” initial MIBI-scintigraphy (MIBI) in patients with primary hyperparathyroidism. Methods: Prospective data were collected regarding 100 consecutive patients, preferentially undergoing a minimally invasive parathyroidectomy (MIP). MIBI was the initial imaging study for localizing a solitary adenoma, followed by US and CT (US/CT) in “MIBI-negative”-patients. Results: Surgery led to normocalcemia in 98 patients (98%) after one operation. Overall 97 patients had solitary parathyroid disease while three patients had multiglandular disease. The sensitivity of imaging increased from 74% for MIBI alone to 92% following subsequent US/CT in “MIBI-negative”-patients. The positive predictive value of a “positive” MIBI was 96% and 76% of a positive US/CT following negative MIBI. The proportion of patients who underwent successful MIP increased from 60 to 72%. Conclusions: MIBI and the combination of US and CT are complementary imaging studies. Additional localization studies after a negative sestamibi scan enhances the number of patients with primary hyperparathyroidism profiting from a minimally invasive approach.

浸润式B超引导下的A超分段式声速测量在致密型白内障眼轴测量中的准确性

目的:观察浸润式B超引导下的A超分段式声速测量在致密型白内障眼轴测量中的准确性。方法:前瞻性研究。选取成都爱尔眼科医院2020-08/2022-08致密型白内障患者86例90眼,男61例59眼,女25例31眼,平均年龄66.49±14.55岁。术前分别采用接触式A超,浸润式B超引导下A超分段式声速测量法与IOL Master 700测量眼轴(AL)、前房深度(ACD)(含角膜厚度)、角膜曲率(K)、晶状体厚度(LT)、中央角膜厚度(CCT)、白到白角膜直径(WTW)。术后1 wk,使用IOL Master 700的无晶状体眼模式复测眼轴长度。分析三种设备测量眼轴的一致性与相关性。结果:术前接触式A超与浸润式B超引导下A超分段式声速测量眼轴为23.40(22.63,23.89)、23.70(23.04,24.25)mm,术后1 wk IOL Master 700测量眼轴为23.72(23.01,24.27)mm。接触式A超与浸润式B超引导下A超分段式声速测量法、术后IOL Master 700测量眼轴差异均有统计学意义(P=0.018),而浸润式B超引导下A超分段式声速测量法与术后IOL Master 700测量眼轴差异无统计学意义(P=0.991)。通过Bland-Altman分析,浸润式B超引导下A超分段式声速测量法与IOL Master 700测量眼轴有很好的一致性(P=0.0809)。术前浸润式B超引导下A超分段式声速测量法与术后IOL Master 700眼轴正相关(r s=0.992,P<0.0001),术前接触式A超与术后IOL Master 700眼轴正相关(r s=0.989,P<0.0001)。结论:对于致密型白内障,浸润式B超引导下A超分段式声速测量比接触式A超更接近术后IOL Master 700眼轴测量数据,具有良好的相关性和一致性。