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Open access

Jorge Camacho, Luis Medina, Jorge F. Cruza, José M. Moreno and Carlos Fritsch

Abstract

Ultrasound is used for breast cancer detection as a technique complementary to mammography, the standard screening method. Current practice is based on reflectivity images obtained with conventional instruments by an operator who positions the ultrasonic transducer by hand over the patient’s body. It is a non-ionizing radiation, pain-free and not expensive technique that provides a higher contrast than mammography to discriminate among fluid-filled cysts and solid masses, especially for dense breast tissue. However, results are quite dependent on the operator’s skills, images are difficult to reproduce, and state-of-the-art instruments have a limited resolution and contrast to show micro-calcifications and to discriminate between lesions and the surrounding tissue. In spite of their advantages, these factors have precluded the use of ultrasound for screening.

This work approaches the ultrasound-based early detection of breast cancer with a different concept. A ring array with many elements to cover 360◦ around a hanging breast allows obtaining repeatable and operator-independent coronal slice images. Such an arrangement is well suited for multi-modal imaging that includes reflectivity, compounded, tomography, and phase coherence images for increased specificity in breast cancer detection. Preliminary work carried out with a mechanical emulation of the ring array and a standard breast phantom shows a high resolution and contrast, with an artifact-free capability provided by phase coherence processing.

Open access

Nan Ge and Siyu Sun

Abstract

The imaging obtained by endoscopic ultrasound (EUS) has improved our understanding of many disease states of the digestive tract. It was mostly utilized by gastroenterologists and surgeons. In this article, we highlight some of the indications and applications that may be noticed by other specialists such as non-small cell lung cancer (by a special EUS technique, i.e., endobronchial ultrasound), pancreatic neuroendocrine tumors, kidney and adrenal masses, rectosigmoid endometriosis, celiac plexus neurolysis and pseudocyst drainage.

Open access

Darko Sazdov, Marija Jovanovski Srceva and Zorka Nikolova Todorova

Abstract

Introduction. Central venous catheterization of the subclavian vein can be achieved with a landmark and an ultrasound-guided method. Using ultrasound the vein can be catheterized with a long axis in plane or a short axis out of plane approach and a combined approach. The aim of the study was to compare the success, average number of attempts and mechanical complication rate between the landmark and the combined ultrasound-guided method.

Methods. A total of 162 adult patients from the Intensive Care Unit at Clinical Hospital Acibadem-Sistina, Skopje were included in this prospective study. Patients randomized in the examined group (n=71) were catheterized with real-time ultrasound guidance with a combined short axis out of plane and long axis in plane method. Patients randomized in the control group (n=91) were catheterized with the landmark method. Subclavian vein was catheterized in both groups. Overall success, success on first attempt, number of attempts and complications at the moment of catheterization were the main outcome measures.

Results. Catheterization using the landmark method was successful in 94.5% of patients, 65.9% of which during the first attempt. Cannulation using real-time ultrasound guidance was successful in all patients with a first pas success of 83.1%. The complication rate in the ultrasound group was 2.82% and 16.5% in the landmark group (p=0.004404).

Conclusion. Real-time ultrasound guidance with a combined short axis out of plane and long axis in plane approach improves success, decreases number of attempts, and reduces mechanical complications rate.

Open access

Irén Csiszér, Silvu Albu, Cristian Mircea Neagos, Marius Navadarszki and Adriana Neagos

Abstract

OBJECTIVE. This study examines the association between the severity of obstructive sleep apnea and the pharyngeal parameters using the ultrasound of the submental region.

MATERIAL AND METHODS. For this study, data obtained from 40 patients, who had undergone investigations in the Galenus Medical Centre in order to diagnose sleep apnea, was analyzed. The following parameters were compared: the transverse diameter of the retrolingual region, the transverse diameter of the retropalatal region and the tongue base thickness. These regions were measured at different moments of respiration such as: during forced expiration, during forced inspiration and while the patients performed Müller’s Manoeuvre. The neck circumference, the body mass index of patients and the severity of sleep apnea obtained from polysomnography were analyzed.

RESULTS. The evaluation of the results revealed: severe obstructive sleep apnea in 16 patients, respectively moderate severity in 10 patients, mild apnea in 4 patients, and no obstructive sleep apnea in 10 patients. Statistically significant results (p<0.05) were found after comparing the parameters obtained in patients with severe apnea versus the parameters in patients without apnea, with mild or respectively moderate apnea.

CONCLUSION. Based on the results obtained, we consider that cervical ultrasound is useful in the diagnosis of severe obstructive apnea, identifying the pathological changes of the anatomical structures that basically cause this category of disease. Due to the fact that in our country ultrasound is a relatively inexpensive method, being also a non-irradiating, repeatable and accessible method, it should be more widely applied also in the field of otorhinolaryngology in order to view structures accessible to this type of imaging.

Open access

Anca Chiriac, Piotr Brzezinski, Anca E. Chiriac, Marius Florin Coroș, Cosmin Moldovan, Cristian Podoleanu and Simona Stolnicu

Abstract

Introduction: The aim of this presentation is to highlight the usefulness of high-frequency ultrasound (18 MHz) in localized morphea for: identification of the lesion, guided skin biopsy, quantification of skin thickness, evaluating the severity by measuring total echogenicity.

Case presentation: A 62-year-old Caucasian woman was referred to the Dermatology Department for a well-circumscribed indurate plaque localized on the right side of the abdominal wall and thigh. On clinical examination, a large well-delimited, indurate plaque, silvery in the center and surrounded by a purplish-red halo (lilac ring) was noticed on the right side of the abdomen and thigh. An ultrasound-guided punch biopsy was carried out and the microscopic examination of the biopsy revealed moderate interstitial inflammatory infiltrate together with abundant collagen bundles in the dermis and subcutis and a diagnosis of localized morphea (scleroderma) was established. Ultrasonography was performed and skin thickness was measured using high-frequency US (18 MHz) and was found to be 3.1 mm to 3.9 mm.

Conclusion: high frequency ultrasound is an inexpensive, easy to perform, noninvasive method, replacing surgical biopsy and offering a valuable quantification of skin fibrosis.

Open access

Stella Pui-Yan Wong and Carmen Ho-Tze Kwan

Abstract

Objective

To document the current state of the use of musculoskeletal US (MSUS) and view on the future development of MSUS training and services among the members of the Hong Kong Society of Rheumatology.

Methods

A three-page anonymous questionnaire, divided into three sections (demographics, current state of the MSUS service, and view on future development of MSUS training and services), was sent (either in electronic format or in hardcopy) to 79 members (70 full members and 9 ordinary members) of the Hong Kong Society of Rheumatology. The aim is to inquire about the use of MSUS by rheumatologists, their views on the future development of MSUS training and service in Hong Kong.

Results

28 (35%) out of 79 members responded to the questionnaire (including 25 fellows and 3 trainees working in public hospitals and private sector). 25 responders (89.3%; 25/28) were using MSUS in their daily practice for making diagnoses, guiding interventions or follow-up disease. Although 90% (25/28) of the responders’ institutes provided the MSUS service by the Radiology Department, 70% of them got long waiting time, and the Radiology Department did not provide the MSUS service to every joint region. Despite the widespread use of MSUS among rheumatologists, more than 90% of the responders could only do less than 10 scans per week. Lack of time and manpower, lack of expertise, high cost of equipment, and lack of support for training were important obstacles in developing the MSUS service. 18 (64%) responders in our survey tended to agree that MSUS training should be incorporated in the rheumatology training.

Conclusions

In conclusion, this is the first survey demonstrating the current state of the use of MSUS in Hong Kong and a huge growth in demand for the service development and formal training in MSUS. A number of challenges in terms of lack of time and manpower, lack of expertise, high cost of equipment, and lack of support for training is evident.

Open access

Wiesław Janusz Kruszewski, Jakub Walczak, Mariusz Szajewski, Tomasz Buczek, Maciej Ciesielski and Jarosław Szefel

The quality of liver assessment in an oncological patient plays an important role in the selection of a proper type of medical intervention. Diagnostic techniques commonly used in liver imaging are still far from perfect. Intraoperative liver evaluation using an intraabdominal ultrasound probe remains an important tool for proper assessment of this organ.

The aim of the study was to evaluate suitability of this intraoperative diagnostic method for detection of primary and secondary neoplastic pathologies of the liver.

Material and methods. Between March 2010 and the end of December 2011, we performed intraoperative ultrasound examinations of the liver during 220 of 461 laparotomies carried out for oncological reasons.

Results. In 72 patients (33%), intraoperative ultrasonography using an intraabdominal probe revealed neoplastic pathologies in the liver. In 16 patients (7%), the pathologies had not been observed in the preoperative imaging examinations. In 7 cases (3%), the detected tumors were impalpable and invisible in macroscopic examination routinely performed during laparotomy. The time of performing preoperative liver examinations did not affect the detection of previously unrecognized liver tumors (p > 0.05). We found progression in the number of liver tumors in 28 patients (39%). In 20 patients (9%), the primary surgical plans were changed intraoperatively.

Conclusions. Liver examination using an intraabdominal ultrasound probe is a useful tool for assessment of neoplastic disease progression. The procedure allows proper choice of an optimal treatment regime and decreases the risk of performing an unnecessary oncological invasive procedure.

Open access

Sanda Jēgere, Inga Narbute, Indulis Kumsārs, Iveta Mintāle, Iļja Zakke, Dace Juhnēviča, Kārlis Trušinskis, Dace Sondore, Aigars Lismanis, Gustavs Latkovskis, Aļona Grāve, Andis Dombrovskis and Andrejs Ērglis

Comparison of Intravascular Imaging and Quantitative Coronary Angiography to Evaluate Neointimal Proliferation after Complex Lesion Stenting

Unlike quantitative coronary angiography (QCA), intravascular imaging methods allow direct visualisation of the arterial wall. Our goal was to determine several intravascular ultrasound (IVUS) and optical coherence tomography (OCT) parameters of neointimal proliferation and stent endothelisation after complex lesion intervention compared to QCA. We examined 261 patients who had underwent percutaneous intervention with bare metal (BMS) or drug eluting stent (DES) implantation for complex coronary lesions and had IVUS or OCT images at six-month follow-up. Percent diameter stenosis (QCA) was 25.2 ± 16.0 in BMS vs 21.7 ± 17.4 in DES (P < 0.05). Percent neointimal volume obstruction (IVUS) was 19.5 ± 14.4 in BMS vs. 5.8 ± 7.7 in DES (P < 0.001). A moderate correlation was observed between QCA and IVUS with an r value of 0.384 overall, 0.472 for BMS and 0.416 for DES (P < 0.001 for all). In patients with chronic total occlusions (n = 161) QCA was similar in BMS and DES patients (P > 0.05) while IVUS showed less neointima in DES (P < 0.05). Total number of uncovered stent struts per OCT image was 0.4 ± 0.8 while per IVUS image 1.2 ± 1.5 (P < 0.001). In conclusion, angiographic indexes correlate with volumetric intravascular parameters. Although IVUS was more sensitive than QCA to assess neointimal proliferation, the assessment of stent endothelisation was more precise using OCT.

Open access

Yuriy Tasinkevych, Ihor Trots, Andrzej Nowicki and Marcin Lewandowski

Abstract

The paper presents the optimization problem for the multi-element synthetic transmit aperture method (MSTA) in ultrasound imaging applications. The optimal choice of the transmit aperture size is made as a trade-off between the lateral resolution, penetration depth and the frame rate. Results of the analysis obtained by a developed optimization algorithm are presented. The maximum penetration depth and lateral resolution at given depths are chosen as optimization criteria. The results of numerical experiments carried out in MATLAB® using synthetic aperture data of point reflectors obtained by the FIELD II simulation program are presented. The visualization of experimental synthetic aperture data of a tissue mimicking phantom and in vitro measurements of the beef liver performed using the SonixTOUCH Research system are also shown.

Open access

Ihor Trots, Andrzej Nowicki, Marcin Lewandowski and Yuriy Tasinkevych

Abstract

Synthetic aperture (SA) technique is a novel approach to present day commercial systems and has previously not been used in medical ultrasound imaging. The basic idea of SA is to combine information acquired simultaneously from all directions over a number of emissions and to reconstruct the full image from these data.

The paper presents the multi-element STA (MSTA) method for medical ultrasound imaging. The main difference with the STA approach is the use of a few elements in the transmit mode in contrast to a single element aperture. This allows increasing the system frame rate, decreasing the number of emissions, and provides the best compromise between the penetration depth and lateral resolution. Besides, a modified MSTA is proposed with a corresponding RF signal correction in the receive mode, which accounts for the element directivity property.

In the experiments a 32-element linear transducer array with 0.48 mm inter-element spacing and a burst pulse of 100 ns duration were used. Two elements wide transmission aperture was used to generate an ultrasound wave covering the full image region. The comparison of 2D ultrasound images of a tissue mimicking phantom obtained using the STA and MSTA methods is presented to demonstrate the benefits of the second one.