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This paper presents a new approach to the accurate determination of the far-field (FF) pattern of wide-angle scanning phased array antennas (PAAs) that uses planar near-field (NF) technology. When PAAs are engaged in wide-angle scanning, a finite scanning plane and inaccurate probe compensation can lead to truncation errors. The proposed approach reduces these by rotating the PAA to make its main beam perpendicular to the scanning plane. To verify the effectiveness of the approach, both theoretical calculations and actual measurements were undertaken. The simulated and measured results prove that the proposed method is more accurate than traditional NF technology for a large PAA scanning angle, such as ψ0=50° and Δ0=50° (in simulation; 54° when measured).

Introduction Ilio-sacral screw fixation has been used for sacral fractures and sacroiliac joint dislocations. However, it is associated with significant complications including screw loosening with backing-out and loss of reduction. Trans-sacral screw fixation is indicated for rigid fixation in specific circumstances including bilateral posterior ring injuries, osteoporotic bone, or to supplement other types of posterior ring fixation. Hypothesis The reformatting the CT scanning plane may distinguish sacral dysmorphism and predict the possibility of trans-sacral screw fixation by introducing the new indicator. Material and methods The CT data of 112 adult cadavers (61 males and 51 females) were imported into Mimics® software and a 7.0 mm-sized trans-sacral screw was virtually placed in the ideal position of S1. The osseous widths around screw in the axial images (AxWS1) were measured. By reformatting the CT scanning plane parallel to the superior endplate of S1, the AxWRS1 was measured and the height of elevated segment in the upper sacrum (elevated height) was assessed as a new preoperative indicator. Results Cortical violation around screw was detected in 26 models and was considered as sacral dysmorphism. The average AxWS1 was measured as 13.70 ± 2.76 mm in the non-dysmorphism group, and 5.81 ± 2.19 mm in the dysmorphism group, with statistical difference (p Discussion By reformatting the CT scanning plane, the osseous width around screw was widened, and the new preoperative indicator of elevated height could be introduced to predict the possibility of trans-sacral screw fixation into S1. If the elevated height exceeded 13 mm, the pelvis was assigned to sacral dysmorphism and thus, could not apply the trans-sacral screw fixation into S1. Level of evidence III, controlled laboratory study.

OBJECTIVE The quality of ultrasound images is impaired in obese patients. All ultrasound scanners are calibrated for an ultrasound propagation velocity of 1540 m/s, but the propagation in fatty tissue is slower (in the order of 1450 m/s). The main objective of this study was to evaluate the quality of images obtained with different ultrasound propagation velocity settings during the mid-trimester fetal ultrasound examination in obese patients. METHODS This was a cross-sectional study using image sets of four recommended scanning planes collected from 32 obese pregnant women during their mid-trimester fetal scan. Each image set comprised three images obtained successively at three different propagation velocity settings (1540 m/s, 1480 m/s and 1420 m/s). A panel of 114 experts assessed the quality of 100 image sets, grading them from A (most acceptable) to C (least acceptable). Scanning-plane-specific indicators of adiposity (fatty layer thickness, probe-to-organ distance) were analyzed for each scanning plane. RESULTS The experts had a mean of 18.1 ± 10.2 years of experience. The grade distribution (A, B, C) differed significantly (P

As society developed expeditiously, more attentions have been paid towards harm of noise. Thus beamforming technology based on phased microphone array is widely used in rotating acoustic source localization. In this paper, a ring microphone array is placed parallel to the scanning plane with the array located on the z-axis. However, the microphone and the rotating part are not allowed to be too close for the potential suction danger caused by the rotating part. At present, this problem has not been solved in engineering.

OBJECTIVES Outlet ventricular septal defects (VSDs) are usually suspected on the five-chamber view of the fetal heart; however, postnatal confirmation occurs only in a small number of cases. The aim of this study was to evaluate if the systematic assessment of the short axis view may improve the prediction of prenatally detected outlet VSDs. METHODS Cases where isolated outlet VSD was suspected on the five-chamber view were assessed by using the short axis scanning plane for confirmation of the defect. Postnatal assessment was performed within 2 weeks from birth at our Paediatric Cardiology Unit. RESULTS An outlet VSD was suspected at five-chamber view in 23 fetuses. Postnatal confirmation of the VSD occurred in 14 cases where the defect was prenatally detected both on the five chamber and the short axis views. VSDs were not confirmed at postnatal assessment only in two cases where outlet VSD was suspected on both views, whereas all the seven cases with a suspected VSD on the five-chamber view only turned out to be false positives. CONCLUSION The short axis view of the fetal heart seems useful in confirming the presence of outlet VSDs. © 2016 John Wiley & Sons, Ltd.

Muscle morphological characteristics obtained via ultrasonography have been used to quantify the size, architecture, and quality of skeletal muscle. Previous research has utilized varying ultrasonographic techniques, however there is little information comparing these different techniques. Muscle morphological characteristics, including cross-sectional area (CSA), muscle thickness (MT), echo intensity (EI), and subcutaneous adipose tissue thickness (SubQ) were assessed in 24 males (20.2 ± 1.6 y) via three panoramic-images captured in the transverse plane (PTI) and three still-images captured in the longitudinal plane (SLI). Cross-sectional area of PTI was significantly greater than CSA of SLI (P

Objectives The aim for the present study was to determine whether projection error of measuring Pauwels’ angle in young femur neck fracture could be eliminated by CT plane manipulation. Methods Clinical data of displaced femur neck fractures in young adults aged 20 to 64 years old (13 females and 17 males) were retrospectively analyzed. Their average age was 47.9 years (range: 22–64 years; SD: 11.3). Using modified measurement method for Pauwels’ angle using central line of the shaft as a guideline, the angle of a conventional coronal CT image was measured. CT images were imported into Mimics® software. The scanning plane was then reformatted parallel to the neck axis to eliminate projection error of injured limb. Measured angles were classified into three types (I 50°) and differences were analyzed. Results Average Pauwels’ angle was 52.9° (range: 28.6–68.3°; SD: 9.9; type II, 17 cases; type III, 13 cases) for conventional CT images and 68.7° (range: 29.8–91.2°; SD: 13.4; type II, 1 cases; type III, 29 cases) for reformatted CT images. Difference between these two measurements on average was 15.7° (range: 1.2–34.9°; SD: 7.3). Conclusions Reformatting CT scanning plane by manipulating the proximal fragment to be parallel with the neck axis of the distal neck-shaft fragment is a convenient and reliable technique for eliminating the projection error of measuring Pauwels’ angle in the femur neck fractures. Level of evidence IV, cohort study.

This paper paper presents the results of a study of the characteristics of the Van Atta array, which is made on the basis of a wideband microstrip antenna. It is shown that the made Van Atta array operates in the frequency band from 1.36 to 2.00 GHz (47% relative to 1.36 GHz). The maximum width of the monostatic RCS is observed at the antenna width in the scanning plane equal to 90 mm and is in the range from 34 to 59 degrees.

Objectives The aim for the present study was to determine whether projection error of measuring Pauwels’ angle in young femur neck fracture could be eliminated by CT plane manipulation. Methods Clinical data of displaced femur neck fractures in young adults aged 20 to 64 years old (13 females and 17 males) were retrospectively analyzed. Their average age was 47.9 years (range, 22–64 years; SD, 11.3). Using modified measurement method for Pauwels’ angle using central line of the shaft as a guideline, the angle of a conventional coronal CT image was measured. CT images were imported into Mimics® software. The scanning plane was then reformatted parallel to the neck axis to eliminate projection error of injured limb. Measured angles were classified into three types (I 50°) and differences were analyzed. Results Average Pauwels’ angle was 52.9° (range, 28.6–68.3°; SD, 9.9; type II, 17 cases; type III, 13 cases) for conventional CT images and 68.7° (range, 29.8–91.2°; SD, 13.4; type II, 1 cases; type III, 29 cases) for reformatted CT images. Difference between these two measurements on average was 15.7° (range, 1.2–34.9°; SD, 7.3) Conclusions Reformatting CT scanning plane by manipulating the proximal fragment to be parallel with the neck axis of the distal neck-shaft fragment is a convenient and reliable technique for eliminating the projection error of measuring Pauwels’ angle in the femur neck fractures. Level of evidence IV, cohort study.

International audience; This paper presents a novel solution to extend the scanning range of a cavity-backed stacked-patch phased array subject to scan blindness. Two main aspects are investigated. The first section is a thorough description of the scan blindness mechanism occurring in the reported array, taking into consideration the characteristics of the associated mutual coupling scheme. The second section introduces a revised array topology that allows extending the scanning range. The proposed solution is based on the switching between two operating modes of the structure, each one covering a distinct scanning range. Taken together, they potentially allow freeing the structure from scan blindness. In the present case, the scanning capability of the array has been extended by 10° in the scanning plane of interest. © 2017 Euraap.

Currently, destructive techniques can be employed to evaluate the internal attributes of fresh fruits, vegetables and nuts. However, clearly not all produce can be evaluated. Thus, there is a need to develop an in vivo non-destructive technique able to assess fresh agricultural commodity internal components, especially disorders. In this study, medical grade computed tomography (CT) was used to obtain transversal two-dimensional (2D) images from several fresh agricultural product phenomena. CT scanning was performed by placing and securing numbered samples onto a whole polyethylene sheet, placed on the CT scanner table. Phenomena included the internal decay of chestnuts (Castanea spp.), internal defects in pickling cucumbers (Cucumis sativus), translucency disorder in pineapples (Ananas comosus), pit presence in tart cherries (Prunus cerasus var. Montmorency) and plum curculio (Conotrachelus nenuphar) infestation of tart cherries. In addition, an ultrafast X-ray CT scanner was also used to visualise internal characteristics of fresh chestnuts. Chestnuts were labelled and packed in a thin plastic hose, which was pulled through the scanning plane. The 2D CT X-ray images and post-processing three-dimensional CT image reconstruction indicate that CT can be used as an accurate in vivo insight of fresh intact agricultural products. Results suggest that there is a potential for non-destructive inline sorting of the internal quality of several agricultural products. The long-term objective is that the fresh and processing product industries will then be able to detect internal quality attributes of fresh agricultural commodities, at a relatively early stage, after validation under commercial conditions.

Article demonstrates possibility of monochromatic radiation usage for relief restoration. There is a problem with restoration when scanned object is not flat and it is not parallel to the scanning plane. It was discovered that two-dimensional phase distribution could be applied for distance determination. It is reliable way to solve problems listed above. In conclusion offered methods allow monochromatic microwave radiation usage for screening system development.

Reconstruction of vascular net of small laboratory animals from MRI data is associated with some problems. This paper proposes a method of MRI data processing which allows to eliminate the fragmentation of reconstructed vascular net. Problem of vessels fragmentation occurs in the case when vessels are parallel to the scanning plane. Our approach is based on multiple scanning, object under consideration is probed by several sets of parallel planes. The algorithm is applied to real MRI data of small laboratory animals and shows good results.

With respect to the assessment of fetal behaviour, there have been numerous reports on the conventional two-dimensional (2-D) ultrasonographic evaluation of fetal movements. However, there are some limitations regarding the assessment of fetal movements using 2-D ultrasound. Because of the 2-D character of real-time scanning, fetal movements outside the scanning plane cannot be displayed on the monitor. The advent of three-dimensional (3-D) ultrasound significantly advanced fetal and placental evaluation in normal and abnormal pregnancies. The introduction of four-dimensional (4-D) ultrasound techniques would allow the assessment of fetal behavioural assessment in three dimensions in real time during pregnancy. We present the latest 4-D sonographic techniques and recent 4-D sonographic studies on fetal behaviour, especially fetal whole-body movements and facial expressions in all three trimesters of pregnancy, and the continuation of behaviour from the fetal to neonatal period. 2-D does not appear capable or comparable to 4-D ultrasound in terms of evaluating early fetal facial expressions. Moreover, we describe the safety of 3-D/4-D ultrasound during pregnancy. This novel technique may assist in the evaluation of fetal behaviour, and offer potential advantages relative to conventional 2-D ultrasound. 4-D ultrasound may be an important modality in future research on fetal neurobehavioural development, although some limitations regarding the assessment of fetal behaviour by means of 4-D ultrasonography still remain unresolved. Copyright © 2009 John Wiley & Sons, Ltd.

OBJECTIVE: To evaluate the usefulness of transendoscopic ultrasound in neurosurgery, we studied two new sonoprobes measuring 6 and 8 French in diameter in 20 fresh specimens. The application and indication are discussed in the first clinical series of 75 patients. METHODS: Sonocatheters (ALOKA, Meerbusch, Germany) 1.9 mm (6 French) and 2.4 mm (8 French) in diameter were introduced into the working channel of an endoscope. The preparations were done in nonfixed skulls in a surgical simulation-setting laboratory. Based on these experiences with imaging possibilities, intraoperative transendoscopic ultrasound was applied in 75 patients and a variety of lesions. It was used for imaging (41 patients), targeting (18 patients), and neuronavigation (16 patients) in neuroendoscopy. RESULTS: The sonoprobe adds a transverse scan at the tip of the probe to the anterior endoscopic view. This axial scan to the longitudinal axis of the endoscope is geometrically comparable with radar scanning. Three probes working with 10, 15, and 20 MHz were used, resulting in a short penetration with a radius of 3 cm. The orthogonal scanning plane had limitations, which were documented. We observed precise imaging of well known anatomic structures and, moreover, achieved an additional dimension in endoscopy. The axial scan presents the anatomic landmarks like a map at the tip of the endoscope where the endoscope is represented as a spot. The real-time imaging and representation of the tip of the endoscope showed a capacity for navigation. This preclinical study rectified clinical application. The real-time imaging of this technique showed the ability of the navigation of endoscopes to detect more overall movements, such as blood flow or change of ventricle size during endoscopy. The primary benefit in this first clinical series was witnessed in difficult endoscopy cases and complex lesions, but benefit was also observed in cases in which vision through the endoscope alone was obscured. The main limitation was the result of little penetration depth and lack of anterior scanning. CONCLUSION: Application of transendoscopic ultrasound is appropriate in neurosurgery. Training is necessary to understand the imaging and the geometry of scans because this technique does not scan along the axis of the endoscope. Further development to overcome the current limits of this technique and more clinical experience are needed.

Both laser scanner and Kinect has been widely used in robotic application for simultaneous localization and mapping (SLAM). However, each sensor has its own limitations. For example, Kinect does not have a wide range field of view and laser scanner could not detect obstacles beyond its scanning plane. The paper proposes a method to combine the data from Kinect and laser scanner to perform a 2D-SLAM. The sensors will be mounted in different types of configurations; both facing forward and facing in opposite directions. This system is able to detect complex surrounding features for better mapping and obstacle avoidance.

To overcome the complexity,high cost of the focal plane of imaging system and long time for scanning,hard to display in real time of the scanning plane of imaging system. Using microwave passive imaging principle,the paper introduces a passive millimeter wave imaging system, describes the imaging principle and system composition structure, and gives a detailed analysis of the key technologies involved in the imaging system.Finally, the results of imaging system are presented.

Intra-articular injections of the hip can be performed to treat a number of pathologic conditions. The drugs administered in these cases may be anti-inflammatory agents, such as steroids that may be indicated for patients with advanced hip osteoarthritis (OA) refractory to other treatments or viscosupplementants, such as hyaluronic acid, that can be used to treat patients with mild to moderate OA. Anesthetics may be injected for diagnostic purposes to differentiate intra- and extra-articular pathology.

Tissue marking with soot-covered fine needles enables the optical coherence tomography (OCT) scanning plane to be localized within the histological specimen to an accuracy of approximately 50 microm. Tissue water content is an especially important parameter for in vitro measurements. Dehydration tends to produce an increase in surface reflections and a reduction in imaging depth.The aim of this in vitro study was to evaluate parameters relevant to the visualization and conservation process to allow optimal images to be generated for later differentiation between healthy and degenerated tissue in vivo.Various methods of marking samples were applied in vitro to achieve accurate overlaps of the OCT scanning plane and the corresponding section of the histological specimen. The influence of temperature and tissue water content was investigated using both porcine and human tissue. Samples were marked using fine needles, ablation craters generated by laser application, and colour markers introduced into the tissue.It was demonstrated that the water content of tissue exerts a direct influence on OCT imaging, whereas above 15 degrees C temperature had no effect on image quality. With regard to the marking of samples, the best results were obtained using sooted fine needles.

Background High-frequency catheter probe US provides detailed images when the scanning plane is perpendicular to the area of interest and the latter is within the focal zone. A multibending endoscope has been developed that has two bending sections that can be deflected independently. The aim of this study was to determine whether this new endoscope enhances high-frequency catheter probe US. Methods High-frequency catheter probe US was performed with the multibending endoscope in 33 patients with upper-GI lesions. The endoscope was carefully maneuvered until the scanning plane was perpendicular to the area of interest and the target area was within the focal zone of the probe. The effects of deflecting the second bending section on the image and on the rotating elements in the probe were evaluated. Results For 28 lesions, no improvement was observed with use of both bending sections. However, for 5 lesions, the US image was improved by use of the second bending section. These lesions were located in the stomach on the lesser or greater curve. In no instance did deflection of both bending sections result in uneven rotation of the mechanical elements in the probe. Conclusions For certain lesions, US images obtained with a catheter probe can be improved by using an endoscope with a second bending section.

Most sonographists have probably encountered cases of liver tumor in which vascular images were distorted or poorly defined when the scanning plane included a tumor in front of a vessel. This phenomenon was thought to results from sound refraction through the tumor. We analyzed this phenomenon first by using the results of clinical studies, then by using the results of basic studies with microcomputer simulation models. Results of clinical studies showed (1) a small notch in vessel walls (29/83, 34.9%) and poor definition of vessels (29/83, 34.9%) appearing behind the tumors, as well as (2) poor vessel definition, predominantly behind heterogenous tumors (28/29, 96.6%). Basic studies showed that vessels appearing behind tumors with homogenous internal structure has a smooth rotation, and that these vessels were visualized as combinations of multiple small fragments behind tumors with heterogeneous internal structure. Refraction of the US beam passing through a tumor, especially one with a heterogeneous internal structure, results in distortion of the US image of vessels located behind such tumors. Familiarity with the pattern of artifactually distorted vessel images can help in preventing misinterpretation of these findings as true pathologic vascular changes. This limitation of sonography necessitates the use of other diagnostic modalities for accurate observation of a vessel situated behind a tumor.

This paper uses a single-layer LIDAR system mounted on a pan-tilt unit to obtain multi-layer information. A calibration method for extending the single-layer information to multi-layer information is proposed. In order to obtain multi-layer information from single-layer LIDAR, the LIDAR system has to tilt the scanning plane at various angles and integrate those scanning planes to construct a three-dimensional model. Ideally, the tilt axis should pass through the center of the scanner. However, since the LIDAR system is mounted on a pan-tilt unit, the tilt axis passes through the motor of the pan-tilt unit, rather than the center of the LIDAR scanner. The positions of the scanning center form a circle. A calibration scheme for transforming all scanning data with respect to one scanning center is proposed. Experimental results show that with the proposed method, the shift error is reduced significantly and the standard deviation of measured distances is reduced to 17% of that for uncalibrated results.

Design and operation of a laser scanning system based on a synchronized scanning geometry is described. Results for scanning plane and cylindrical surfaces are reported. Deviations of the experimental results from that of the expected theoretical ones are presented. The described system offers a good reproducibility and results agree well with the theory. The results obtained from our system are satisfactory and show a promise in order to be used in the real applications. The reported approach can also be used in the design of a three-dimensional vision system.

Endoluminal ultrasonography with small-caliber and high-frequency transducer is suitable for transcanal assessment of middle ear with effusion. An endoluminal ultrasound transducer (size 6 French, 20 MHz) with a side-viewing scanning plane was used to image 12 ears of six children suspected of having effusion in the middle ear. Sonographic findings were compatible with those of operation in 10 diseased ears. One false-negative result was obtained, and one trial was aborted owing to trauma to the canal wall. The present study proves utility in demonstrating fluid behind the tympanic membrane. A promising use of endoluminal ultrasonography for middle ear evaluation might be expected if some modification could be made to the transducer.

The blood realizes the transport of substances, which are necessary for livelihoods, throughout the body. The assumption about the relationship genotype and structure of vasculature (in particular of brain) is natural. In the paper we consider models of vessel net for two genetic lines of laboratory mice. Vascular net obtained as a result of preprocessing MRI data. MRI scanning is realized using the method of variation of slope of scanning plane, i.e. by several sets of parallel planes specified by different normal vectors. The following special processing allowed to construct models of vessel nets without fragmentation. The purpose of the work is to compare the vascular network models of two different genetic lines of laboratory mice.

A thorough literature review on current research for trisomy 21 detection using ultrasound will be carried out for existing modality’s drawback investigation. Due to its critical restriction, computing on ultrasound markers in term of its recognition, segmentation and measurement are essentially required. 3D reconstruction of nuchal translucency becomes a breakthrough to select the appropriate scanning plane of ultrasound markers. It shall resolve the problematic issue on scanning plane selections which depends on operator assumption and experience. Data sources from hospital patient scanning should obtain the approval from Medicine ethical committee. Consent and simple agreement document shall be prepared. The main ultrasound images sources will be taken from Health Center Universiti Teknologi Malaysia, Hospital Universiti Sains Malaysia, and Hospital Universiti Kebangsaan Malaysia. External collaboration parties are Hospital Sultanah Aminah and Technische Universitat Ilmenau, Germany. Other than fetal data, maternal health data will also be recorded. This data is important to obtain the knowledge of correlation between fetal and mother data. It is recommended that pregnant women should be older than 30 years old. This chapter will describe the book in terms of its background, history and the related works in greater detail. The focus will be on the Trisomy 21 background, history, existing detection techniques, and ultrasound application using 2D and 3D image formation on fetal abnormalities detection. Previous related research works are discussed and each of their limitation is remarked.

OBJECTIVE. The purpose of this study was to compare a novel MRI sequence—3D fast-recovery fast spin-echo (FRFSE) cube—with a standard 2D FRFSE sequence for the investigation of uterine anomalies.CONCLUSION. Compared with 2D FRFSE, 3D FRFSE cube provides superior image quality and improved 3D reconstructions in a shorter acquisition time and enables excellent visualization of uterine anatomy in any orientation, regardless of the original scanning plane.

In order to test the ability of a 4-row CT scanner (GE Light Speed RT) to display breathing motion of isolated lung tumors, a motion phantom was scanned at different velocities. The phantom consists of a solid wooden sphere (4cm diameter) oscillating along its middle axis at a period of 4s with 1.4cm amplitude peak to peak. Scanning was done in two different modes: In axial mode with 4s image acquisition time and in helical mode with exposure times between 1.0s and 2.8s. Phantom motion in the scanning plane and perpedicular to it were investigated separately.

A novel method of planar near-field scattering measurements, i.e. the method of self-transmitting and self-receiving (STSR) planar near-field scattering measurements is studied in theory and validated experimentally. The experiment results show that the relative value of scattering property obtained by means of this method has good engineering precision in an angle range near the outward normal direction of the scanning plane, which proves the correctness, validity and engineering practicability of this method.

A large-area scanning system using 14 MeV tagged neutrons has been built. The associated 4 He particles emitted in the D+T reaction are detected in an array of Parallel Plate Avalanche Counters that defines a scanning plane having about 10 × 100 cm 2 area. Coincident gamma-rays are detected by 10 BaF 2 scintillators. The capability of the system to determine the presence and the position of samples and to perform an on-line background subtraction is demonstrated. Test with landmines are also reported. This technique allows a significant improvement of the signal-to-noise ratio searching for hidden threat materials. The use with portable sealed-tube generators is foreseen.

A large area scanning system using 14 MeV tagged neutrons has been built. The associated 4He particles emitted in the D + T reaction are detected in an array of Parallel Plate Avalanche Counters that defines a 10 × 100 cm2 area in the scanning plane. Coincident gamma-rays are detected by 10 BaF2 scintillators. The commissioning of the sensor has been completed. The capability of the system to determine the presence and the position of samples has been verified. Furthermore the possibility of on-line background subtraction is demonstrated.

Background: The availability of an electronic radial scanning echoendoscope has facilitated the clinical use of tissue harmonic imaging. This study compares the quality of US images acquired by tissue harmonic imaging during electronic radial scanning EUS to those acquired by fundamental imaging. Methods: Electronic radial scanning EUS was performed in 108 patients with pancreatic lesions (58 cystic, 50 solid). US images acquired by fundamental imaging at a frequency of 7.5 MHz were compared with those acquired by tissue harmonic imaging by using transmitting and receiving frequencies of, respectively, 4.0 and 8.0 MHz at the same scanning plane. Cystic lesions were evaluated for boundary/septum and nodules, and solid lesions, for boundary and internal structure. US images acquired by tissue harmonic imaging and fundamental imaging during electronic radial scanning EUS were compared, by using a Likert scale for the respective evaluation criteria, by two independent endoscopists. Observations: For cystic lesions, tissue harmonic images were significantly clearer than fundamental images for visualizing boundary and septum ( p p = 0.0003, Reviewer 1; p = 0.0007, Reviewer 2). For solid lesions, tissue harmonic images were significantly clearer than fundamental images for visualizing boundary ( p = 0.0003, Reviewer 1; p p = 0.0003, Reviewer 1; p = 0.0009, Reviewer 2). Conclusions: US images acquired by tissue harmonic imaging appear to be clearer compared with those acquired by fundamental imaging.

If the transducer is directed ventrally, the scanning plane in the body moves with the direction of the rotation (right rotation moves the transducer to the right side of the body)

The technique of self-transmitting and self-receiving (STSR) monostatic planar near-field scattering measurements is studied and computer simulated. Calculation results indicate the relative value of monostatic RCS obtained by means of self-transmitting and self-receiving monostatic planar near-field scattering measurements has good engineering precision in an angle range near the outward normal direction of the scanning plane. Finally, several problems that need to be further studied are pointed out.

The purpose of this study was to describe and evaluate a method for assessing the sound propagation velocity in breast tumors relative to the velocity in adjacent tissue.Sixty-six patients with palpable breast tumors were studied. The scanning plane was aligned so that it transected the tumor and depicted the front of a rib or the pleura-lung interface behind the tumor. This contour was evaluated for distortion, and the height of the distortion and the height of the tumor were used to calculate the relative sound propagation velocity.A posterior reference line was revealed behind 62 of 66 tumors. Of these 62 tumors, an elevation was seen behind 49 tumors, and no distortion was seen behind 13 tumors. A depression was never observed. The median relative sound propagation velocity of 1.07 that was calculated in 42 carcinomas (range, 1.00-1.14) was insignificantly higher (p = .079) than the median relative sound propagation velocity of 1.04 obtained in 20 fibroadenomas (range, 1.00-1.15).Although assessment of relative sound propagation velocity in breast tumors was successful, the relative velocities differed only insignificantly between benign and malignant lesions.

Three-dimensional interpretation of fish images from a sector scanning sonar to determine the shape and the distribution of fish schools was investigated. The sonar drove a half-circular cylindrical array transducer, which was mechanically rotatable on two axes. It emitted 2ms acoustic pulses of 160kHz in a half-circular plane omnidirectionally, then received echoes by scanning the insonified plane. In general use, the scanning plane is tilted a few degree downward from the surface, and the fish school echoes are indicated on a display as a PPI image around the ship. Therefore we can only observe fish echoes as a two-dimensional image, even if the scanning plane is tilted largely from the surface.

Conventional C-scan ultrasonic techniques are excellent for imaging two dimensional defects such as delaminations, cracks, and plate type inclusions [1]. This technique is most effective when these defects are oriented parallel to the scanning plane. However, for three-dimensional inclusions difficulties are encountered when the conventional scanning technique is adopted. If one wants to reconstruct the three dimensional inclusion from generated C-scan images at different depths a significant amount of error is introduced in its size and shape. Even for a simple 3D object such as a sphere it is often difficult to accurately estimate its size and location from its C-scan generated image.

Conventional two-dimensional (2D) echocardiography provides high-resolution images of the beating heart that allow accurate qualitative and quantitative estimation of structure and function1. However, 2D echocardiography visualizes only one tomographic plane at a time and then it requires the operator to reconstruct in his mind a composite view of the heart using multiple 2D images acquired from different acoustic windows. In fact, especially in the presence of regional abnormalities as induced by ischemic heart disease, a single tomographic plane often does not allow a correct diagnosis. Furthermore, we have shown that standard 2D echocardiographic imaging planes that are assumed to be orthogonal to each other commonly are not2, undermining the accuracy of both qualitative diagnosis and of quantitative measurements that rely on assumed geometric models.

Transesophageal echocardiography with use of a uniplane phased-array transducer with a transverse or horizontal scanning plane has become a well-established tool for evaluating cardiovascular diseases. Recent introduction of biplane probes has enhanced the diagnostic capability of this imaging technique. This article discusses the technique of biplane transesophageal echocardiographic examination and image orientation. The diagnostic value and advantages of various biplane transesophageal images of the heart, aorta, and aortic arch from various esophageal positions are described.

Purpose: To characterize couch sag on a CT scanner and determine the impact on patient treatments. A CT couch sags as it enters the gantry, and the amount depends on couch design, material, patient weight and distribution. Method and Materials: Four individuals were placed on a CT scanner couch (GE Discovery Lightspeed). A dial indicator was fixed to the bore of the CT scanner to measure couch deflection at the scanning plane when the couch was extended to various lengths. A second experiment was performed to measure sag at various positions for a fixed couch extension. A steel I‐beam with the dial indicator mounted on a rail was placed underneath the CT and tomotherapy couches. Two uniform loads were placed on the couch for three couch extensions and measurements were recorded at discrete locations. Results: Two forms of couch sag relevant to radiotherapy were observed: absolute and intra‐target sag. Absolute sag was shown to be 8.0±0.5 mm. Intra‐target sag depended on the S‐I length of the target and could be 2.3±0.5 mm. Both CT and tomotherapy couches displayed similar sag patterns. Differences in sag between the couches were more pronounced at short cantilevered distances with a maximum difference of 1 mm. Conclusion: A significant amount of sag occurs at the scanning plane resulting in a shearing of the images used for treatment planning. Absolute sag may be corrected by a couch height adjustment but intra‐target sag is a concern for elongated targets. The impact of sag on tomotherapy treatments is minimal since the relative difference in sag patterns between CT and tomotherapy couches is small. However, differences between CT and tomotherapy couch sag have become a concern for facilities treating total marrow irradiation (TMI) fields with tomotherapy. Conflict of Interest: Mackie has a financial interest in TomoTherapyInc.

A method and system for indicating the position and orientation of a scan plane relative to a patient is provided. The image as presented on a display is oriented in accordance with the orientation of a transducer. The orientation may provide for displaying an image where the transducer is not in a transducer up or transducer down position, but is rotated away from vertical of the display. Alternatively or additionally, a two or three-dimensional graphical generic representation is provided with a scan plane indicated as a polygon or image rendering within a generic representation to show relative positioning of the scan plane with respect to the patient.

The authors used a gantry tilt of 20 degrees in five patients to allow fine-needle aspiration biopsy of peripheral pulmonary lesions that were difficult to approach with a vertical alignment because of overlying ribs. This method allowed a direct approach to the lesion in all five cases, with the entire needle path visible in the scanning plane, avoidance of vital structures, and traversal of a minimal amount of normal lung parenchyma.

In an ultrasonic imaging system, an ultrasonic angiographic image of a blood vessel, equivalent to an X-ray angiographic image, is produced in a real time by utilizing an IIR digital filter with a ROM and a frame memory. The ultrasonic imaging system comprises: a scanning unit for scanning a biological body under medical examination within a three-dimensional scanning plane involving the biological body by utilizing ultrasonic pulses to obtain echo signals produced from echo pulses reflected from the biological body; an ultrasonic image data producing unit for producing a plurality of ultrasonic scanned image data about the scanned biological body with regard to the respective scanning planes in response to the echo signals; a bloodflow-distribution image data producing unit for producing a plurality of bloodflow-distribution image data about the scanned biological body with regard to the respective scanning planes in response to the echo signals; a storage unit for temporarily storing the plurality of bloodflow-distribution image data, while sequentially updating and superimposing the plural bloodflow-distribution image data with each other during a predetermined scanning period.

At 1188 patients we investigated the value of sonography of the breast in the detection of malignancies. We used 2 automatic multitransducer water-bath scanners, at first the 3 MH Octoson, then System 1, a dedicated 4 MH water-bath breast scanner which allows for compound and simple scans in any scanning plane. The sensitivity for detection of 63 malignancies was 87%. Other pathologies were 18 fibroadenomas, 160 cysts, 6 abscesses, 2 fatty necroses, 2 papillomas, 9 prostheses, one of them broken. The difficulties associated with differential diagnosis in breast sonography are discussed in detail.

The adrenal glands were evaluated in 70 normal volunteers using linear-array real-time ultrasonography. All the scanning approaches described for manual B-scanning were used and, on the left side, longitudinal scans along the axillary lines were also performed. The right adrenal gland was imaged in 68 of the 70 volunteers and the left gland in 63. The dynamic capabilities of real-time equipment were of great help for proper localisation and identification of the glands. Changes in the scanning plane demonstrated variations in the adrenal morphology, because different portions of the gland were encountered by the scanning beam.

Varying results have been reported concerning the echogenicity of normal superficial tendons. Our recent results using high-resolution real-time linear-array equipment indicate that the normal tendons display a specific echogenic longitudinally oriented fibrillar pattern. However, the visualization of this normal texture requires a perfect technique of examination. The obliquity of the ultrasound beams in relation to the tendon in longitudinal scans as well as the nonrespect of the strict perpendicularity of the scanning plane in transverse sections result in an artifactual hypoechogenicity of the normal tendon. Since hypoechogenicity has been shown a diagnostic criterion for inflammatory changes in tendons, the awareness of this pitfall is instrumental in preventing a false-positive diagnosis of tendinitis.

The ultrasonic findings in a case of small bowel intussusception in an adult patient are presented. The sonographic features vary with the scanning plane. Scans along the longitudinal axis of the involved segment show a diagnostic pattern, not previously described: three parallel stripes of low echogenicity delineating two reflective areas.