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B-scan ultrasonography (USG) is a simple, non-invasive tool for diagnosing lesions of the posterior segment of the eye. Ocular conditions that hinder fundoscopy such as cataract, lens dislocation/ subluxation, vitreous degeneration, vitreous haemorrhage, retinal detachment, ocular trauma, ocular tumours such as metastasis, choroidal melanoma can be accurately evaluated with this modality. In addition to being cost effective, it is non-invasive, easily available, produces high resolution images and its results are reproducible. An understanding of the basic anatomy of the eye, the US technique, and common pathological entities affecting the eye will allow radiologists to readily diagnose these entities and thus guide the referring ophthalmologist in choosing the treatment. This article focuses on the common ocular pathologic conditions that affect the eye particularly the posterior ocular segment and their pictorial representation in B scan ultrasonography.

Neuro-ophthalmologists commonly receive referrals for possible papilloedema. One common cause of oedematous-appearing optic nerves is optic disc drusen (ODD). We describe a novel, handheld, portable ultrasound device that can be used to identify ODD in cases of suspected papilloedema. We demonstrate here that this portable ultrasound system can detect ODD in the outpatient ophthalmology and neurology settings. The portable version demonstrates several advantages. The device can be carried into the office, readily reducing visit times and office space. It is much more affordable than a traditional ultrasound machine. Images can be uploaded to a secure server and imported into the patient's chart. These cases represent one potential ophthalmological application of this novel technology that could augment the ophthalmological examination and improve patient care in the future. [ABSTRACT FROM AUTHOR]

Background: The ultrasound B-scan is one of the most commonly used ophthalmic investigations in day-to-day practice. It is a noninvasive investigative modality to assess the posterior segment of the eye and is irreplaceable in patients with hazy or opaque media. Purpose: This video aims to summarize a few tips for beginners to help them perform and interpret a B-scan with ease. Synopsis: In this video, we have briefly described the principle of B-scan using animations. The various scanning techniques and probe orientations have been demonstrated using short video clips. We have also summed up the indications and how various clinical entities appear in a B-scan. Highlights: The teaching points include the principle, indications, probe orientations, and how common retinal pathologies appear in a B-scan. Video link: https://youtu.be/lUlUvShIy9A.

Background: the use of handheld ultrasonography (HHUS) devices is well established in prehospital emergency diagnostics, as well as in intensive care settings. This is based on several studies in which HHUS devices were compared to conventional high-end ultrasonography (HEUS) devices. Nonetheless, there is limited evidence regarding potential variations in B-scan quality among HHUS devices from various manufacturers, and regarding whether any such differences hold clinical significance in intensive care medicine settings. Methods: this study included the evaluation of eight HHUS devices sourced from diverse manufacturers. Ultrasound videos of five previously defined sonographic questions (volume status/inferior vena cava, pleural effusion, pulmonary B-lines, gallbladder, and needle tracking in situ) were recorded with all devices. The analogue recording of the same pathologies with a HEUS device served as gold standard. The corresponding findings (HHUS and HEUS) were then played side by side and evaluated by sixteen intensive care physicians experienced in sonography. The B-scan quality and the clinical significance of the HHUS were assessed using a five-point Likert scale (5 points = very good; 1 point = insufficient). Results: both in assessing the quality of B-scans and in their ability to answer clinical questions, the HHUS achieved convincing results—regardless of the manufacturer. For example, only 8.6% (B-scan quality) and 9.8% (clinical question) of all submitted assessments received an "insufficient" rating. One HHUS device showed a significantly higher (p < 0.01) average points score in the assessment of B-scan quality (3.9 ± 0.65 points) and in the evaluation of clinical significance (4.03 ± 0.73 points), compared to the other devices. Conclusions: HHUS systems are able to reliably answer various clinical intensive care questions and are—while bearing their limitations in mind—an acceptable alternative to conventional HEUS devices. Irrespective of this, the present study was able to demonstrate relevant differences in the B-scan quality of HHUS devices from different manufacturers. [ABSTRACT FROM AUTHOR]

Background: Handheld ultrasound (HHUS) devices have chiefly been deployed in emergency medicine, where they are considered a valid tool. The data situation is less clear in the case of internal questions in abdominal sonography. In our study, we investigate whether HHUS devices from different manufacturers differ in their B-scan quality, and whether any differences are relevant for the significance of an internal ultrasound examination. Method: The study incorporated eight HHUS devices from different manufacturers. Ultrasound videos of seven defined sonographic questions were recorded with all of the devices. The analogue recording of the same findings with a conventional high-end ultrasound (HEUS) device served as an evaluation criterion. Then, the corresponding findings were played side by side and evaluated by fourteen ultrasound experts using a point scale (5 points = very good; 1 point = insufficient). Results: The HHUS devices achieved relatively good results in terms of both the B-scan quality assessment and the ability to answer the clinical question, regardless of the manufacturer. One of the tested HHUS devices even achieved a significantly (p < 0.05) higher average points score in both the evaluation of B-scan quality and in the evaluation of clinical significance than the other devices. Regardless of the manufacturer, the HHUS devices performed best when determining the status/inferior vena cava volume and in the representation of ascites/free fluid. Conclusion: In various clinical abdominal sonography questions, HHUS systems can reliably reproduce findings, and are—while bearing their limitations in mind—an acceptable alternative to conventional HEUS systems. Irrespective of this, the present study demonstrated relevant differences in the B-scan quality of HHUS devices from different manufacturers. [ABSTRACT FROM AUTHOR]

Suspected optic disc swelling is a common presentation in children. The delineation between true optic disc swelling and pseudopapilloedema, its common masquerade, requires careful evaluation. A streamlined pathway is required to avoid unnecessary investigations. Papilloedema requires urgent neuroimaging, however, perceived optic disc swelling is not always true papilloedema. This study aims to investigate the outcome of referrals for optic disc swelling and formulate features that may assist in investigation and diagnosis. A retrospective review of referrals for optic disc swelling to the Queensland Children's Hospital, Australia, between January 2014 and June 2020 was undertaken. Four hundred and ten children were referred for optic disc swelling. Sixty-six patients were confirmed with optic disc swelling, and 344 patients had pseudopapilloedema. The average age was 10.10 ± 3.57 and 9.90 ± 3.50 years, respectively. The most common aetiology of optic disc swelling was idiopathic intracranial hypertension (n = 25). Optic disc drusen constituted the majority of pseudopapilloedema (n = 239) and the remainder were crowded/tilted discs (n = 105). True optic disc swelling patients were more likely to experience headache (OR = 8.68, p < 0.01) and visual disturbance (OR = 2.14, p = 0.03). B-scan was the most sensitive for the detection of optic disc drusen (100%), followed by optical coherence tomography (70.38%) and fundus autofluorescence (44.86%). The retinal nerve fibre layer thickness was significantly thicker in true optic disc swelling compared to pseudopapilloedema (p < 0.01). Twenty-two (33.33%) true optic disc swelling patients and 33 (9.59%) pseudopapilloedema patients underwent neuroimaging prior to ophthalmology review. Suspected optic disc swelling in children is most likely pseudopapilloedema. Referrals should include neurological assessment, visual acuity, fundus photography, and optical coherence tomography to assist in the triage for ophthalmic review. Neuroimaging prior to ophthalmic review should be discouraged for children without neurological symptoms. [ABSTRACT FROM AUTHOR]

A 20-year-old vegetarian male presented with a history of painful diminution of vision in the right eye for the past month. The patient had dense vitritis. B-scan ultrasonography (USG) revealed two cysts with scolices, one subretinally along with retinal detachment and another one in vitreous cavity. Orbital USG revealed no cystic lesions in the orbit or extraocular muscle. He underwent 23 gauge pars plana vitrectomy. Both intravitreal and subretinal cysts were cut and aspirated using cutter and removed from the eye, and silicon oil was injected. Postoperatively he was started on oral steroids and advised to maintain prone positioning for two weeks. At two months his best corrected visual acuity (BCVA) in the right eye was 20/125 with silicon oil in situ.

Aims: A meaningful sonographic examination is decisively dependent on the B-scan quality of the ultrasound device. When selecting a suitable ultrasound device, B-scan quality should be an important purchase criterion. Although there is no generally accepted method to measure B-scan quality, we tried to evaluate comparable sonography devices from different manufacturers regarding B-scan quality. Material and methods: We systematically assessed the B-scan quality in ultrasound devices of seven different manufacturers from the mid-price segment. All 7 ultrasound units tested had comparable equipment features and the purchase value of approximately $20,000. We recorded video sequences and compared B-mode image quality. We used both physiological sectional images and pathological findings from abdominal ultrasound. Results: We identified three ultrasound units that scored significantly better in measuring the B-scan quality than the other devices. The Canon Xario 200, the General Electric Logiq P7 and the Mindray DC70 (in alphabetical order) were the units that outperformed all others. The differences identified were found to be statistically significant. A subgroup analysis showed that the contrasts in quality were more pronounced in near-field examinations than in examinations with greater penetration depth. Conclusions: There are considerable qualitative discrepancies in B-scan ultrasound devices despite being similar in terms of equipment and price. Our findings show that these differences are statistically detectable and likely clinically relevant. [ABSTRACT FROM AUTHOR]

Optical coherence tomography (OCT) imaging has become a useful tool in medical diagnosis over the past 25 years, because of its ability to visualize intracellular structures at high resolution. The main objective of this work is to add electronic feedback to the optical coherence tomography setup to increase its sensitivity. Noise added to the measured interferogram obscures some details of examined tissue layered structure. Adjusting signal power level in such a way to improve signal-to -noise ratio can help to enhance image quality. Electronic feedback is added to enhance system sensitivity. A logarithmic amplifier is included in the OCT setup to automatically adapt signal level. Moreover, the resolution of the optical spectrum analyzer is controlled according to the farthest layer detected in the A-scan. These techniques are tested showing an improvement in obtained image of a human nail. [ABSTRACT FROM AUTHOR]

When ultrasounds are blocked by some obstacles or some areas cannot be illuminated by ultrasounds due to the complex shape of targets, the targets may not be detected by ultrasonic testing (UT). Thus, a simple and direct full-angle synthetic aperture focusing technique (SAFT) is proposed to conquer the above-mentioned difficulties, and its performance will be evaluated and compared with the commonly used B-scan SAFT. Two types of the full-angle scan are introduced in this study, the first one is the four-side scan which comprises top-, right-, bottom-, and left-side scans. The second is the circular scan which the transducer circulates and faces the center of the object during scanning. Then the acquired scan data is processed by SAFT. Study results show that the images of full-angle SAFT are significantly superior to the image of the traditional B-scan SAFT. This indicates the ultrasonic detection ability is largely improved by the full-angle SAFT. However, the traditional B-scan SAFT is simple and direct which is recommended to detect the existence of the shallowest targets. For detecting the deeper targets, which may be blocked by some obstacles, the four-side scan SAFT is suggested since this method has a better detection capability to detect the extreme positions of the targets. The image of the circular scan SAFT is fine, which shows this technique has a better focus capability since the transducer inspects the specimen from full-azimuth. Thus, to reveal the shape of being blocked target, the circular scan SAFT is suggested. [ABSTRACT FROM AUTHOR]

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Objectives: To compare the effectiveness of fluid-air exchange with silicone oil-fluid exchange in reducing the residual silicone oil (SO) droplets after the removal of SO. Methods: This was a prospective, quasi-experimental study conducted from October 2021 to February 2022 at Eye Unit-III, COAVS, Mayo Hospital, Lahore. Sixty-one patients with siliconized eyes underwent removal of SO with two different techniques and were divided into fluid-air exchange and oil-fluid exchange groups. To quantify the residual silicone droplets objectively, B-scan echographic images were analyzed within seven days of surgery. Silicone oil index (SOI) which is the amount of residual SO droplets/vitreal area in the images was calculated with the help of imagej software. Results: The residual SOI of the fluid-air exchange group (0.99 ± 1.76%) was significantly lower than the oil-fluid exchange group (3.25 ± 3.85%). The SOI is positively correlated with the duration of tamponade, preoperative intraocular- pressure and axial length. Persistent IOP elevation post-operatively was seen in 16.67% individuals in the fluid-air exchange group and 54.8% individuals in the oil-fluid exchange group. Conclusion: Fluid-air exchange group was found to be superior in reducing residual SO droplets than the oil-fluid exchange group. [ABSTRACT FROM AUTHOR]

Background: Handheld ultrasound (HHUS) devices have chiefly been deployed in emergency medicine, where they are considered a valid tool. The data situation is less clear in the case of internal questions in abdominal sonography. In our study, we investigate whether HHUS devices from different manufacturers differ in their B-scan quality, and whether any differences are relevant for the significance of an internal ultrasound examination. Method: The study incorporated eight HHUS devices from different manufacturers. Ultrasound videos of seven defined sonographic questions were recorded with all of the devices. The analogue recording of the same findings with a conventional high-end ultrasound (HEUS) device served as an evaluation criterion. Then, the corresponding findings were played side by side and evaluated by fourteen ultrasound experts using a point scale (5 points = very good; 1 point = insufficient). Results: The HHUS devices achieved relatively good results in terms of both the B-scan quality assessment and the ability to answer the clinical question, regardless of the manufacturer. One of the tested HHUS devices even achieved a significantly (p < 0.05) higher average points score in both the evaluation of B-scan quality and in the evaluation of clinical significance than the other devices. Regardless of the manufacturer, the HHUS devices performed best when determining the status/inferior vena cava volume and in the representation of ascites/free fluid. Conclusion: In various clinical abdominal sonography questions, HHUS systems can reliably reproduce findings, and are—while bearing their limitations in mind—an acceptable alternative to conventional HEUS systems. Irrespective of this, the present study demonstrated relevant differences in the B-scan quality of HHUS devices from different manufacturers.

Background: the use of handheld ultrasonography (HHUS) devices is well established in prehospital emergency diagnostics, as well as in intensive care settings. This is based on several studies in which HHUS devices were compared to conventional high-end ultrasonography (HEUS) devices. Nonetheless, there is limited evidence regarding potential variations in B-scan quality among HHUS devices from various manufacturers, and regarding whether any such differences hold clinical significance in intensive care medicine settings. Methods: this study included the evaluation of eight HHUS devices sourced from diverse manufacturers. Ultrasound videos of five previously defined sonographic questions (volume status/inferior vena cava, pleural effusion, pulmonary B-lines, gallbladder, and needle tracking in situ) were recorded with all devices. The analogue recording of the same pathologies with a HEUS device served as gold standard. The corresponding findings (HHUS and HEUS) were then played side by side and evaluated by sixteen intensive care physicians experienced in sonography. The B-scan quality and the clinical significance of the HHUS were assessed using a five-point Likert scale (5 points = very good; 1 point = insufficient). Results: both in assessing the quality of B-scans and in their ability to answer clinical questions, the HHUS achieved convincing results—regardless of the manufacturer. For example, only 8.6% (B-scan quality) and 9.8% (clinical question) of all submitted assessments received an “insufficient” rating. One HHUS device showed a significantly higher (p < 0.01) average points score in the assessment of B-scan quality (3.9 ± 0.65 points) and in the evaluation of clinical significance (4.03 ± 0.73 points), compared to the other devices. Conclusions: HHUS systems are able to reliably answer various clinical intensive care questions and are—while bearing their limitations in mind—an acceptable alternative to conventional HEUS devices. Irrespective of this, the present study was able to demonstrate relevant differences in the B-scan quality of HHUS devices from different manufacturers.

Magnetically Mediated Thermoacoustic Imaging (MMTAI) is a new imaging technology that uses the thermoacoustic effect of electromagnetic fields. It is capable of a high resolution in ultrasonic imaging and high contrast in electrical impedance imaging. It has considerable potential applications in the early diagnosis of diseases. First, this paper describes the theoretical analysis and numerical simulation of MMTAI. For B-scan thermoacoustic imaging, the thermoacoustic image of a two-dimensional model is simulated and analyzed. The numerical simulation results provide theoretical guidance for the design of the experiment. Second, the B-scan experimental system of MMTAI is designed and built. The imaging experiment was carried out using an imitation gel that contains sodium chloride as the target, and the imaging results were basically consistent with the conductivity distribution of the target. Numerical simulation and physical experiments verify the feasibility of the MMTAI method for low conductivity media. This preliminary study has shown the feasibility of the technique to detect conductivity boundaries, making it relevant for the future application of this method in the field of biomedical imaging. [ABSTRACT FROM AUTHOR]

(1) Background: Computed tomography (CT) is considered mandatory for assessing the extent of pathologies in the paranasal sinuses (PNS) in chronic rhinosinusitis (CRS). However, there are few evidence-based data on the value of ultrasound (US) in CRS. This multicenter approach aimed to compare diagnostic imaging modalities in relation to findings during surgery. (2) Methods: 127 patients with CRS were included in this prospective multicenter study. Patients received preoperative US and CT scans. The sensitivity and specificity of CT and US were extrapolated from intraoperative data. (3) Results: CT scans showed the highest sensitivity (97%) and specificity (67%) in assessing CRS. Sensitivities of B-scan US were significantly lower regarding the maxillary sinus (88%), the ethmoid sinus (53%), and the frontal sinus (45%). The highest overall sensitivity was observed for assessing the pathology of the maxillary sinus. (4) Conclusions: We observed high accuracy with CT, confirming its importance in preoperative imaging in CRS. Despite the high US expertise of all investigators and a standardized examination protocol, the validity of CT was significantly higher than US. Ultrasound of the PNS sinuses is applicable in everyday clinical practice but lacks diagnostic accuracy. Nevertheless, it might serve as a complementary hands-on screening tool to directly correlate the clinical findings in patients with PNS disease. [ABSTRACT FROM AUTHOR]

Annotated datasets play a significant role in developing advanced Artificial Intelligence (AI) models that can detect bridge structure defects autonomously. Most defect datasets contain visual images of surface defects; however, subsurface defect data such as delamination which are critical for effective bridge deck evaluations are typically rare or limited to laboratory specimens. Three Non-Destructive Evaluation (NDE) methods (Infrared Thermography (IRT), Impact Echo (IE), and Ground Penetrating Radar (GPR)) were used for concrete delamination detection and reinforcement corrosion detection. The authors have developed a unique NDE dataset, Structural Defect Network 2021 (SDNET2021), which consists of IRT, IE, and GPR data collected from five in-service reinforced concrete bridge decks. A delamination survey map locating the areas, extent and classes of delamination served as the ground truth for annotating IRT, IE and GPR field tests' data in this study. The IRT were processed to create an ortho-mosaic maps for each deck and were aligned with the ground truth maps using image registration, affine transformation, image binarization, morphological operations, connected components and region props techniques to execute a semi-automatic pixel–wise annotation. Conventional methods such as Fast Fourier transform (FFT)/peak frequency and B-Scan were used for preliminary analysis for the IE and GPR signal data respectively. The quality of NDE data was verified using conventional Image Quality Assessment (IQA) techniques. SDNET2021 dataset consists of 557 delaminated and 1379 sound IE signals, 214,943 delaminated and 448,159 sound GPR signals, and about 1,718,083 delaminated and 2,862,597 sound IRT pixels. SDNET2021 addresses one of the major gaps in benchmarking, developing, training, and testing advanced deep learning models for concrete bridge evaluation by providing a publicly available annotated and validated NDE dataset. [ABSTRACT FROM AUTHOR]

This observational study compared optic coherence tomography (OCT) and B-scan in the detection of optic disc drusen. In total, 86 eyes of 50 patients with optic disc drusen (ODD) (36 bilateral) with a mean age of 34.68 ± 23.81 years, and 54 eyes of 27 patients with papilledema, with a mean age of 35.42 years ± 17.47, were examined. Patients with ODD, diagnosed with ultrasound, underwent spectral-domain OCT evaluation. With US, 28 ODD cases were classified as large (4 buried and 24 superficial), 58 were classified as point-like (6 buried, 49 superficial and 3 mixed). Then, all patients underwent OCT. OCT was able to detect the presence of ODD and/or peripapillary hyperreflective ovoid mass structure (PHOMS) in 69 eyes (p < 0.001). In particular, 7 eyes (8.14%) showed the presence of ODD alone, 25 eyes (29.07%) showed only PHOMS and 37 eyes (43.02%) showed ODD and PHOMS. In 17 eyes (19.77%) no ODD or PHOMS were detected. In the papilledema group, no ODD were observed with both US and OCT. OCT showed the presence of drusen or similar lesions in only 80.23% of the cases highlighted by the US scan, so it does not allow for certain ODD diagnoses, especially in the case of buried ODD. [ABSTRACT FROM AUTHOR]

To describe choroidal calcifications as an ophthalmic feature in aplasia cutis congenita (ACC) with oculoectodermal syndrome (OES). Two cases of ACC/OES with characteristic echographic evidence of choroidal calcifications are described. The ophthalmic manifestations of ACC/OES may be expanded to include choroidal calcifications. The presence of a choroidal calcification with B-scan ultrasound in a case suspicious for ACC/OES may facilitate a more timely diagnosis and inform future follow-up regimens to monitor ophthalmic and systemic manifestations of this disease. [ABSTRACT FROM AUTHOR]

The diagnostics of the optic nerve (ON) pathology relies on the results of clinical and instrumental examinations, electrophysiological tests, computer tomography and magnetic resonance imaging. The potentials of these techniques are often limited, and the costs high. Ultrasound examination is noninvasive, informative and relatively inexpensive. The literature review is focused on the role of echography in the diagnosis and diagnostic differentiation of optic nerve pathologies. The data on the techniques of measurements of the optic nerve sheath diameter (ONSD) and its normal parameters are presented. In addition to eye pathology, B-scanning of the optic nerve is a very useful diagnostic method in cerebral pathology and systemic diseases. In clinical practice, the measurement of the main acoustic and biometric characteristics of ON plays a crucial role in the assessment of severity of damage and treatment effectiveness of ON pathology. The comparability of measurements of intraocular and retrobulbar ON parts using the different imaging techniques will require further studies.

Objectives: To investigate the relationship between choroidal nevus and melanoma thickness measured with or without the sclera included by B‐scan ultrasound and to present a simple conversion formula. Methods: Medical records were retrospectively reviewed for choroidal nevus or melanoma evaluated at the Mayo Clinic in Rochester, Minnesota, with B‐scan ultrasound between February 4, 2004, and April 23, 2020. Charts were retrospectively reviewed for high‐quality B‐scan images in which the ultrasound transducer was perpendicular to the lesion, measuring the tumor thickness without the sclera included. Measurements were repeated with the sclera included for each patient. Univariate and multiple linear regression analyses were performed to identify factors correlated with scleral thickness. Results: There were 201 tumors included in the study, with a mean patient age ± SD of 61 ± 14 years, largest tumor basal diameter of 11.8 ± 4.8 mm, tumor thickness without the sclera included of 3.72 ± 2.7 mm, and thickness with the sclera included of 4.54 ± SD 2.8 mm. On the univariate analysis, factors associated with perceived scleral thickness by B‐scan ultrasound included age (P <.001), tumor thickness (P <.001), and basal diameter (P =.06). On the multivariate analysis, factors associated with perceived scleral thickness included age and tumor thickness (P <.001) for all tumors and for the subset of 141 tumors with a thickness of 2 mm or greater (P <.001). For tumors of 2 mm or greater in thickness, perceived scleral thickness by ultrasound can be estimated by the formula 0.00495(patient age) + 0.02451(tumor thickness without the sclera) + 0.42549. Conclusions: We present a simple formula for converting between B‐scan ultrasound measurements of choroidal nevus and melanoma measuring 2 mm or greater in thickness with and without the sclera included. [ABSTRACT FROM AUTHOR]

Chinese lacquerware is an important invention of arts and crafts in China. In this study, Chinese lacquerware is characterized using terahertz reflectometric imaging. The lacquerware studied herein comprises an ornamental wood panel covered by multiple layers of lacquers to portray motifs. For characterizing lacquerware, a terahertz time-domain spectroscopic reflectometric imaging system is proposed. The role of the proposed terahertz imaging system in highlighting the interface between layers during stratigraphic buildup in reflection geometry is proved. The proposed system provides a universal method for assessing the structural information of lacquered objects in a contactless and non-invasive manner; moreover, it provides two-dimensional images, subsurface three-dimensional images, and stratigraphic images (b-scans) in a contactless and non-invasive manner. Using the proposed system, we examine the buried layers of the lacquerware, including faults in the wooden layer and damages in the lacquerware. Research shows the promising prospects of terahertz time-domain spectroscopic reflectometric imaging as a non-destructive detection technique suited to lacquerware.

When ultrasonic time-of-flight diffraction (TOFD) B-scan is implemented along the circumferential direction of pipeline, the ray path of direct longitudinal wave (DLW) is not parallel to the curved pipeline surface, inducing the layered dead zone. In this paper, the spectrum analysis method based on Fourier transform is employed to establish the relationship between flaw depth and harmonic frequency interval. On this basis, the relative position between flaw tip and DLW is determined combining with the characteristics of the tip-diffracted waves in B-scan image, realizing the quantitative detection of the defects with different depths. Simulated and experimental results show that the range of dead zone in pipeline is reduced by 40% with spectrum analysis method, and the relative quantitative errors of flaw depths are within 11%. Finally, the formation mechanism of extreme values for the tip-diffracted waves in B-scan image is discussed by theoretical analysis. [ABSTRACT FROM AUTHOR]

Quality assurance (QA) is the maintenance of a desired level of quality in a service, by means of attention to every stage of process of delivery. Correct image acquisition along with accurate and reproducible quantification of ophthalmic imaging is crucial for evaluating disease progression/stabilization, response to therapy, and planning proper management of these cases. QA includes development of standard operating procedures for the collection of data for ophthalmic imaging, proper functioning of the ophthalmic imaging equipment, and intensive training of technicians/doctors for the same. QA can be obtained during ophthalmic imaging by not only calibration and setting up of the instrument as per the manufacturer's specifications but also giving proper instructions to the patients in a language which they understand and by acquisition of good quality images. This review article will highlight on how to achieve QA in imaging which is commonly being used in ophthalmic practice.

Purpose: To determine the frequency of posterior segment pathologies caused by ocular trauma using B scan USG. Study Design: Descriptive, cross-sectional study. Place and Duration of Study: Holy family hospital, Rawalpindi, from September 2015 to March 2016. Methods: One hundred patients of ocular trauma, 12 to 45 years of age were included in the study. Patients who had any posterior segment pathology prior to the ocular trauma were excluded. B scan was performed in all patients. The data was collected and analyzed using SPSS version 17. For all the categorical variables like gender, type and site of ocular injury, the side of eye involved, type of posterior segment pathology as detected on B Scan, frequencies and percentages were calculated. For the continuous variables like age and time since injury, mean and standard deviation were calculated. Results: Mean age was30.43 ± 9.58 years. Majority of the patients (35.0%) were between 26 to 35 years of age. Out of these 100 patients, 73 were males and 27 were females with male to female ratio of 2.7:1. Vitreous hemorrhage was the most common and ocular pathology (38 patients). Retinal detachment was seen in 21 patients. Intra-ocular foreign bodies were seen in 12 patients. Conclusion: Vitreous hemorrhage was the most common posterior segment pathology in ocular trauma followed by retinal detachment and intra-ocular foreign bodies. [ABSTRACT FROM AUTHOR]

Background: To investigate the incidence of developing posterior vitreous detachment (PVD) in children after congenital cataract surgery. Methods: This is a prospective study which recruited 131 children with congenital cataracts who underwent cataract surgery between June 1, 2015, and September 1, 2018. The patients were divided into two groups depending on their post-operation phakic status (with or without IOL implantation). Infants aged from 6 to 12 months from two groups were analyzed as subgroups, respectively. B-scan ultrasonography was performed before the procedure and at 1, 3, 6, 9, and 12-month follow-ups, respectively, after the operation. Results: Of the 131 eyes included in the analyses, 74 were aphakic, and 57 were pseudophakic after surgery. The postoperative rate of PVD in all analyzed eyes was 6.9% (9 of 131 eyes). After 12 months, PVD was significantly more prevalent in the eyes that underwent cataract surgery with IOL implantation (10.5%, 6 of 57 eyes) compared to the eyes without IOL implantation (4.1%, 1 of 74 eyes, P < 0.05); however, the eyes in the aphakic group were significantly younger than the eyes in the pseudophakic group, while the mean axial length (AL) of the pseudophakic eyes (21.11 ± 2.07 mm) was significantly higher than that of the aphakic eyes (18.93 ± 1.86 mm) (P < 0.01). In patients between the ages of 6 and 12 months of age from the two groups, the AL of patients with IOL implantation continued to be significantly increased compared to the group without IOL implantation (20.44 ± 1.68 mm vs. 19.78 ± 1.52 mm, P < 0.01). At the follow-up appointments, two patients with PVD were observed among the 14 eyes that had undergone cataract surgery with IOL implantation, while one eye was observed to have developed PVD among the 15 eyes without IOL implantation. Conclusions: PVD occurs with greater frequency after congenital cataract surgery, particularly in eyes that have undergone IOL implantation. We suggest that PVD should be carefully monitored in children after congenital cataract surgery to avoid subsequent ocular pathologies such as retinal detachment. Future studies are needed to determine other potential risk factors that have not been as thoroughly explored, as opposed to better-known factors such as older age, longer axial length, and IOL implantation. [ABSTRACT FROM AUTHOR]

Retina and vitreous abnormalities represent the most common eye disorders in diabetic patients; they may be associated with severe complications. Therefore, this study aimed to study the prevalence of vitreous and retinal pathologies in diabetic patients using B-Scan ultrasound (U/S). A total of two hundred and three Sudanese diabetic patients with long diabetic disease duration (mean 16.28 ± 4.830) years were enrolled in a descriptive-analytical study. 55% (n = 112) were males and 45% (n = 91) were females. The mean age of the participants was 62.28 ± 8.041(range between 30-79 years -old). The study was conducted in a Sudanese ophthalmologic hospital in Khartoum, during the period from 2016–2019. A Nidek (Echoscan US–4000) - B-scan ultrasound unit with 10 MHZ transducer was used. A high-frequency direct contact technique was applied. The inclusion criteria included adult diabetic patients. The vitreous and retina disorders were more prevalent in diabetic hypertensive participants 55 % (n = 112). The high frequency of the disorders was observed in age groups: 60–69 and 50–59 years-old. The most common disorder was retinal detachment which was detected in 30.5% (n = 62) followed by vitreous changes in16.3% (n = 33). Posterior vitreous was observed in 15.8% (n = 32), vitreous hemorrhage seen in 15.3% (n = 31), both retinal detachment with vitreous hemorrhage were detected in 11.3%) (n = 23), retinal detachment with cataract were reported in 3.4% (n = 7), retinal detachment with Vitreous changes were seen in 3% (n = 6), and other changes were noted in 4.4% (n = 9) of the participants. There is no significant a statistical association between gender/diabetic duration and age with the disorders (P = 0.2, 0.43, and 0.5) respectively. Vitreous & Retinal disorders were more prevalent in diabetic hypertensive patients. The high frequency of the disorders was observed in the age group (50–70). The ultrasound is a useful method in diagnosing Vitreous & Retinal disorders among the diabetics. [ABSTRACT FROM AUTHOR]

The results of investigating the parameters of ultrasonic signals when increasing rail testing speed presented. Signals from rail bolt holes were selected as test reflectors. It is shown that the holes closest to rail joints are not sounded fully, and signals due to them cannot be used as test reflectors. For a full assessment of the deterioration of the quality of nondestructive testing of rails with an increase in the scanning speed, it is proposed to use the integral indicator of the reflector being analyzed. A noticeable decrease in this indicator at high speeds requires a compromise decision when choosing between performance and quality of rail inspection. The proposed technique can be used to assess the efficiency of operating and newly created flaw detection systems. The necessity of improving the methods of sounding the first bolt holes of the joints and adjusting the normative documents in relation to high-speed control of rails is substantiated. [ABSTRACT FROM AUTHOR]

Optical coherence tomography (OCT) is an evolving medical imaging technology that offers in vivo cross-sectional, sub-surface images in real-time. OCT has become popular in the medical as well as non-medical fields. The technique extensively uses for food industry, dentistry, dermatology, and ophthalmology. The technique is non-invasive and works on the Michelson interferometry principle, i.e., dependent on back reflections of the signal and its interference. The objective is to develop an algorithm for signal processing to construct an OCT image and then to enhance the quality of the image using image processing techniques like filtering. The image construction was primarily based on the Fourier transform (FT) of the dataset obtained by data acquisition. This FT could be performed rapidly with the extensively used algorithm of fast Fourier transform (FFT). The depth-wise information could be extracted from each A-scan, i.e., axial scan and also the B-scan was obtained from the A-scan to see the structure of sample. The maximum penetration depth achieved with proposed system was 2.82mm for 1024 data points. First and second layer of leaf were getting at thickness of 1mm and 1.6mm, respectively. A-scans for Human fingertip gave its first, second and third layer was at a thickness of 0.75mm, 0.9mm and 1.6mm, respectively. A-scans for foam sheet gave its first, second and third layer was at a thickness of 0.6mm, 0.75mm, and 0.85mm, respectively. [ABSTRACT FROM AUTHOR]

Primary hyperplastic persistent vitreous (PHPV) or persistent fetal vasculature is a rare clinical entity that presents with leucocoria, microphthalmos, and cataract. It is mostly unilateral. Here we present a report of two cases of bilateral PHPV. One of the patients had associated Peters’ anomaly. The entity closely mimics retinoblastoma and should be kept as a differential diagnosis of bilateral leucocoria. Examination under anesthesia, ultrasound B-scan, and aqueous lactate dehydrogenase levels helped us reach the diagnosis and differentiate it from the more serious entity retinoblastoma.

Ground Penetrating Radar (GPR) is extensively employed for underground target detection, and the advancements in this domain have been hastened by the utilization of deep learning methodologies. Despite advancements in deep learning, practical engineering applications often face challenges in meeting the demanding requirements of large-scale data and high data quality. In this study, based on cross-domain transfer learning, we proposed a method for underground target classification of weak labeled GPR data. It combined strongly annotated source domain data with weakly annotated target domain data through adversarial learning to leverage the prior knowledge from existing large datasets and addressed the classification problem of small-sample GPR data. By employing adversarial learning to integrate strongly labeled source domain data with weakly labeled target domain data, we leverage prior knowledge from existing large datasets, thereby enhancing classification accuracy on a small GPR dataset. This approach reduces the requirements for annotation quality and sample quantity in the GPR B-scan dataset of underground targets. Additionally, it exhibits robustness to label noise, making it applicable to real-world GPR data classification tasks. Compared to some well-known networks, the proposed model achieved the best classification performance in multiclass classification problems, with an accuracy of 87.62% and an F1 macro score of 87.60% on the test set. These results represent an improvement of 17.14 and 17.20 percentage points, respectively, over the best-performing classical classification networks. Additionally, the proposed model's reliability in cross-domain transfer learning, even with limited data, was substantiated through a comparison with other few-shot learning networks. • Innovating GPR B-scan classification via weak-shot learning • Cross-domain transfer learning boosts accuracy, addressing data limitations effectively. • Highly practical, SimTrans-GPR outperforms traditional algorithms. • Resilient to label noise, applicable to real-world GPR data classification tasks. [ABSTRACT FROM AUTHOR]

Background: the use of handheld ultrasonography (HHUS) devices is well established in prehospital emergency diagnostics, as well as in intensive care settings. This is based on several studies in which HHUS devices were compared to conventional high-end ultrasonography (HEUS) devices. Nonetheless, there is limited evidence regarding potential variations in B-scan quality among HHUS devices from various manufacturers, and regarding whether any such differences hold clinical significance in intensive care medicine settings., Methods: this study included the evaluation of eight HHUS devices sourced from diverse manufacturers. Ultrasound videos of five previously defined sonographic questions (volume status/inferior vena cava, pleural effusion, pulmonary B-lines, gallbladder, and needle tracking in situ) were recorded with all devices. The analogue recording of the same pathologies with a HEUS device served as gold standard. The corresponding findings (HHUS and HEUS) were then played side by side and evaluated by sixteen intensive care physicians experienced in sonography. The B-scan quality and the clinical significance of the HHUS were assessed using a five-point Likert scale (5 points = very good; 1 point = insufficient)., Results: both in assessing the quality of B-scans and in their ability to answer clinical questions, the HHUS achieved convincing results-regardless of the manufacturer. For example, only 8.6% (B-scan quality) and 9.8% (clinical question) of all submitted assessments received an "insufficient" rating. One HHUS device showed a significantly higher ( p < 0.01) average points score in the assessment of B-scan quality (3.9 ± 0.65 points) and in the evaluation of clinical significance (4.03 ± 0.73 points), compared to the other devices., Conclusions: HHUS systems are able to reliably answer various clinical intensive care questions and are-while bearing their limitations in mind-an acceptable alternative to conventional HEUS devices. Irrespective of this, the present study was able to demonstrate relevant differences in the B-scan quality of HHUS devices from different manufacturers.

As they pointed out, the standardized A-scan technique might provide more accurate and objective results for measuring optic nerve sheath diameter (ONSD) compared to B-scan technique. Keywords: A-scan; B-scan; intracranial hypertension; ocular ultrasonography; optic nerve sheath diameter EN A-scan B-scan intracranial hypertension ocular ultrasonography optic nerve sheath diameter 766 767 2 02/06/23 20230301 NES 230301 In reply We thank Dr Martina De Luca and colleagues for their thoughtful letter. B-scan, A-scan, ocular ultrasonography, intracranial hypertension, optic nerve sheath diameter. [Extracted from the article]

Quality assurance (QA) is the maintenance of a desired level of quality in a service, by means of attention to every stage of process of delivery. Correct image acquisition along with accurate and reproducible quantification of ophthalmic imaging is crucial for evaluating disease progression/stabilization, response to therapy, and planning proper management of these cases. QA includes development of standard operating procedures for the collection of data for ophthalmic imaging, proper functioning of the ophthalmic imaging equipment, and intensive training of technicians/doctors for the same. QA can be obtained during ophthalmic imaging by not only calibration and setting up of the instrument as per the manufacturer's specifications but also giving proper instructions to the patients in a language which they understand and by acquisition of good quality images. This review article will highlight on how to achieve QA in imaging which is commonly being used in ophthalmic practice. [ABSTRACT FROM AUTHOR]