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BACKGROUND Metastatic colorectal cancer (mCRC) is a complex and heterogeneous disease with few standard and targeted treatment options. Next-generation sequencing of tumor tissue was performed to identify cancer driver mutations to discover possible personalized treatment options, as targeted treatment possibilities are limited for this patient population. Results of genomic sequencing in patients with treatment-refractory mCRC are described in this retrospective analysis. MATERIAL AND METHODS Clinico-pathological characteristics and genomic sequence results of consecutive patients with refractory mCRC, referred to the Experimental Cancer Therapy Unit (ECTU) at Department of Oncology, Herlev & Gentofte Hospital in the period from 1 October 2015 to 14 December 2018 were reviewed in this retrospective analysis. Tumor tissue from the patients was analyzed by next-generation sequencing using the Oncomine Comprehensive primer panel to detect actionable variants of cancer driver mutations and microsatellite instability status. From August 2018 tumor mutational burden was also analyzed. RESULTS A total of 80 patients with treatment-refractory mCRC and in a fairly good performance were referred to the ECTU during this period. Genomic sequencing of tumor tissue was performed for all 80 patients and a cancer driver mutation was identified in 90% (n = 72) of the patients. A total of 31.3% (n = 25) of the patients received therapy either as targetable therapy outside an available trial (n = 2), FDA approved therapy (n = 2), or treatment in phase 1 or 2 trials, independent of the genomic signature 26.3% (n = 21). CONCLUSION Most mCRC patients refractory to standard anti-neoplastic therapies, presented with a cancer driver mutation, however, only a few of these mutations gave rise to matched therapies as only 2.5% of the patients from this period received targeted therapy.

HgCdTe films grown by liquid phase epitaxy were passivated with CdTe grown by molecular beam epitaxy. A series of annealing tests with different temperatures and durations were then carried out in order to reach a two-fold goal: to smooth the gradients in Hg and Cd content across the HgCdTe film-passivation interface, and to create a Hg vacancy concentration of ∼ 1–2 × 1016 cm−3. We want the composition gradient to prevent minority carrier electrons from reaching the actual interface, as this may contain recombination centers that trap the electrons. Four different temperature–time combinations were tried for the first part of the annealing procedure (the smoothing of gradients), while they were all followed by a Hg vacancy procedure of 250°C for 18–24 h. Then some samples were cleaved, and energy-dispersive x-ray spectroscopy (EDS) line profiles were recorded on the cross sections to monitor the composition gradients. We could clearly see differences between the profiles from samples with the higher-temperature annealing, the lower-temperature annealing and no annealing. Secondary ion mass spectroscopy profiles on two samples verified the EDS results. On another subset of similar samples, planar diodes were processed and resistance-area (RA) values determined. The current–voltage (I–V) curves from the high-temperature annealed samples seemed dominated by leakage current and did generally not display diode characteristics. This could be explained by their EDS profiles, which showed a lot of Hg in the entire passivation layer. The EDS profiles from the three low-temperature annealing procedures were very similar, but planar diode I–V curves revealed diodes of varying quality, and their RA values were used to differentiate among them. The optimal annealing procedure was 300°C for 4 h, followed by 250°C for 24 h.

The aim of this article is to provide an inventory of the use of contrast-enhanced ultrasound (CEUS) in relation to percutaneous interventional procedures. The article is structured into a systematic literature review followed by a clinical part relating to percutaneous CEUS-guided procedures. A literature search identified 3109 records. After abstract screening, 55 articles were analyzed and supplemented with pictorial material to explain the techniques. In conclusion, the best-evidenced indications for CEUS-guided interventions are biopsy and ablation of inconspicuous or B-mode-invisible tumors, intraprocedural ablation control and follow-up, as well as percutaneous transhepatic cholangiography and drainage procedures.

This is the second part of the series on interventional ultrasound guidelines of the Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). It deals with the diagnostic interventional procedure. General points are discussed which are pertinent to all patients, followed by organ-specific imaging that will allow the correct pathway and planning for the interventional procedure. This will allow for the appropriate imaging workup for each individual interventional procedure (Long version).

This is the first part of the Guidelines on Interventional Ultrasound of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) and covers all general aspects of ultrasound-guided procedures (short version; the long version is published online).

The term gallbladder polyp (GBP) refers to any elevated lesion on the surface of the gallbladder mucosa. The majority of GBPs are so-called pseudopolyps (cholesterol-polyps, focal adenomyomatosis, hyperplastic polyps or inflammatory polyps) with no malignant potential. True GBPs includes adenomas and adenocarcinomas. Gall bladder adenomas (GBA) are benign; however, they might have a malignant potential as seen in the adenoma-carcinoma sequence in colo-rectal cancer. It is; however, unclear how often adenocarcinomas have arisen from pre-existing adenomas. GBPs are commonly detected as incidental findings on ultrasound (US) of the abdomen or on the histological examination after cholecystectomy. Pseudopolyps are far more likely to be of size 10 mm in size. Patients with polyps of 10 mm or greater should be treated with cholecystectomy. Small GBPs Growth of GBPs Single GBPs are more likely to be malignant than multiple GBPs; and sessile GBPs are significantly more commonly associated with malignancy probably because most gallbladder cancers arise from flat dysplastic epithelium. The diagnostic challenge is to identify the small group of patients with malignant and premalignant GBPs where surgically treatment (cholecystectomy) is indicated, and spare the remaining large group of patients with non-malignant and non-premalignant GBP for unnecessary cholecystectomy and unnecessary follow-up exams. Unnecessary cholecystectomies should be limited to avoid the potential complications related to this procedure. Unnecessary follow-up exams should be limited to reduce the economic cost related hereto; and to reduce the fear that is introduced when a patient is told that “something in the gallbladder has to be controlled”. Unfortunately, the level of evidence regarding guidelines for follow-up and treatment of GBP is low; and randomized controlled trials are lacking. Based upon best practice, I suggest these recommendations: GBP > 10 mm: Surgical treatment (cholecystectomy) is recommended. GBP of 7-9 mm: Follow-up after 12 and 36 months is recommended. If (during the follow-up period) the GBP size increases 2 mm or if the GBP size reaches 10 mm, surgical treatment (cholecystectomy) is recommended. GBP of 6 mm and less: No treatment or follow-up is recommended.

The recently developed Norwegian Earth System Model (NorESM) is employed for simulations contributing to the CMIP5 (Coupled Model Intercomparison Project phase 5) experiments and the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC-AR5). In this manuscript, we focus on evaluating the ocean and land carbon cycle components of the NorESM, based on the preindustrial control and historical simulations. Many of the observed large scale ocean biogeochemical features are reproduced satisfactorily by the NorESM. When compared to the climatological estimates from the World Ocean Atlas (WOA), the model simulated temperature, salinity, oxygen, and phosphate distributions agree reasonably well in both the surface layer and deep water structure. However, the model simulates a relatively strong overturning circulation strength that leads to noticeable model-data bias, especially within the North Atlantic Deep Water (NADW). This strong overturning circulation slightly distorts the structure of the biogeochemical tracers at depth. Advancements in simulating the oceanic mixed layer depth with respect to the previous generation model particularly improve the surface tracer distribution as well as the upper ocean biogeochemical processes, particularly in the Southern Ocean. Consequently, near-surface ocean processes such as biological production and air–sea gas exchange, are in good agreement with climatological observations. The NorESM adopts the same terrestrial model as the Community Earth System Model (CESM1). It reproduces the general pattern of land-vegetation gross primary productivity (GPP) when compared to the observationally based values derived from the FLUXNET network of eddy covariance towers. While the model simulates well the vegetation carbon pool, the soil carbon pool is smaller by a factor of three relative to the observational based estimates. The simulated annual mean terrestrial GPP and total respiration are slightly larger than observed, but the difference between the global GPP and respiration is comparable. Model-data bias in GPP is mainly simulated in the tropics (overestimation) and in high latitudes (underestimation). Within the NorESM framework, both the ocean and terrestrial carbon cycle models simulate a steady increase in carbon uptake from the preindustrial period to the present-day. The land carbon uptake is noticeably smaller than the observations, which is attributed to the strong nitrogen limitation formulated by the land model.

The aim of this study was to demonstrate and evaluate the ultrasound-guided drainage of deep pelvic abscesses in which transabdominal percutaneous access could not be performed because of overlying structures. A retrospective analysis of 32 consecutive patients with 33 deep pelvic abscesses was performed. The underlying causes of the abscesses included postsurgical fluid collection or surgical complications in 18 of the 32 patients, and 11 of these patients underwent recent rectal cancer surgery. The locations of the abscesses, which had a median diameter of 6 cm (range 2-10 cm), were as follows: perirectal (n=13), presacral (n=9), pouch of Douglas (n=7), internal genitals (n=2) and between the bowel loops (n=2). The abscesses were all drained using ultrasound (US) guidance with a transrectal (n=18), transvaginal (n=11), transperineal ( n=2) or transgluteal (n=2) approach. Of the larger abscesses (median diameter 7 cm), 19 were treated with catheter drainage and 18 of these cases resulted in favorable clinical outcomes. Of the smaller abscesses (median diameter 4 cm), 14 were treated with needle drainage. In two of these cases, follow-up US showed that a repeat puncture and drainage was necessary. All needle drainages resulted in favorable clinical outcomes. Sixteen of the 29 transrectal or transvaginal drainage procedures were performed without any anesthesia (10 were performed with a needle and six were performed with a catheter). Apart from minor discomfort during the drainage procedure and the subsequent in-dwelling catheter period, there were no serious complications related to the drainage procedures. We conclude that ultrasound-guided transrectal, transvaginal, transperineal and transgluteal drainage of deep pelvic abscesses are safe and effective treatment approaches. Based on our findings, needle drainage will be our most common first-line treatment approach because of the simplicity of the procedure, improved patient comfort and reduced costs. Catheter drainage will be reserved for large multiloculated abscesses.

Percutaneous needle biopsy is almost exclusively performed under imaging guidance, using either ultrasound or computed tomography. Although accepted as a relatively safe procedure, percutaneous needle biopsy is certainly not risk-free. One of the potential serious complications after a percutaneous biopsy is tumor seeding which is relatively poorly understood and documented. Neoplasm seeding is defined as a local implantation of tumor cells by contamination of instruments and surgical equipment resulting in local growth of the cells and tumor formation (according to the National Library of Medicine of the National Institutes of Health, USA). Frequency and mechanisms behind tumor seeding after biopsy are poorly elucidated. In the four largest surveys the range of the needle tract seeding after biopsy of abdominal lesions was miniscule (0–0.009%). Common to these relatively old studies was that they were based on patient and doctor reporting, without performing an active cross-sectional imaging verified tracing of seeding; and therefore the true seeding rate was probably greatly underestimated. Sparsely documented incidences in the more recent studies of the colorectal neoplasm seeding following liver biopsy vary between 10% and 19%. These data consist primarily of relative small case series and reports limited by small sample size. The reported high seeding rates are therefore probably greatly overestimated in these studies. Some authors suggest that invasive diagnostic procedures should be carefully considered due to risk of seeding which can change a potentially respectable localized cancer to an unrespectable one. Neoplasm seeding has been a subject of particular concern for liver surgeons. Tumor seeding is a well-known phenomenon after traditional open surgical procedures as well as after laparoscopic procedures. Tumor seeding has also been reported after ultrasound guided radiofrequency ablative procedures. Experimental studies have shown cancer cell leakage in the needle tract in the majority of biopsy cases. How do we reduce tumor seeding? The co-axial biopsy technique, whereby the biopsy needle is inserted through an introducing needle, is popular with many practitioners who cite improved needle stability and the ability to obtain multiple cores using only one initial puncture as strong advantages of this system. It has been suggested that the co-axial technique reduces the risk of needle tract seeding by isolating the biopsy specimen from the needle tract when the sample is withdrawn. Unfortunately no randomized studies have proved this yet. Furthermore, seeding after using the co-axial biopsy technique has been described. The use of contrast enhanced ultrasound can reduce the need for ultrasound guided liver biopsy in many cases, and this procedure should be reserved to unclear cases approved by the local multidisciplinary team and to cases where oncologic treatment is planned.

Purpose The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS). Materials and methods 39 patients (17 women and 22 men) with a total of 125 liver metastases were treated with percutaneous or intraoperative CEUS-guided MW ablation. The primary tumor was colorectal cancer (n = 31), breast cancer (n = 6), carcinoid tumor (n = 1), and gastrointestinal stromal tumor (GIST) (n = 1). The median number of metastases ablated in the 45 treatment sessions was 2 (range 1 - 11). The median size (maximum diameter) of the 125 metastases was 1.5 cm (range, 0.6 - 4.0 cm). Nineteen (15 %) of the 125 metastases were bigger than 2 cm. Metastases smaller than 2 cm were treated with a single needle, metastases bigger than 2 cm were treated with 2 or 3 parallel needles. Results The 45 MW ablation sessions were performed percutaneously (n = 30), during laparotomy (n = 3), or during laparotomy combined with liver resection (n = 12). The 39 patients were followed up for at least 4 months with a median duration of 11 months (range, 4 - 20 months). The technical success rate was 100 %. The clinical effectiveness was 100 % with complete coverage of the metastasis by the avascular coagulation zone evaluated on immediate post-ablation CEUS. Local tumor progression (local recurrence) was seen in 12 (9.6 %) of the 125 treated metastases, and affected 10 (26 %) of the 39 patients. One major complication was observed in the form of a liver abscess that easily resolved after percutaneous drainage. Four minor complications were observed: Three cases of pain located at the puncture site and one case of ascites. CEUS was valuable in all phases of ablation including pre-ablation staging and procedure planning, placement of MW needles in the tumor, immediate post-ablation control of coagulation size, and finally in the long term follow-up regime. Conclusion CEUS-guided MW ablation of liver metastases is an efficient and safe ablation technique with several advantages compared to other ablation modalities.

This paper presents results from recent work on molecular beam epitaxy growth of HgCdTe at the Norwegian Defence Research Establishment (FFI), including studies of material properties and fabrication of photodiodes and nanostructures. Systematic studies of defect morphology in HgTe and Hg1� xCdxTe have revealed that there is a minimum in the area covered by defects just below the onset of Te precipitation. The shape and density of microvoids in HgTe can be used to determine the deviation from the optimal growth temperature. This can be further related to the optimal growth temperature of Hg1� xCdxTe with any Cd mole fraction by thermodynamic calculations. A mechanism for the formation of microvoids and needles has been presented. Photoluminescence (PL) has been used to study layers without doping and with Hg vacancy, Ag, and In doping. Planar photodiodes with high dynamic resistance and good quantum efficiency were fabricated by ion-milling vacancy-doped mid-wave and long-wave infrared layers. Quantum wells (QWs) with good crystallinity and high PL light output have been grown. Surface patterning has been found to enhance light emission from HgCdTe thin-film and QW samples by � 30%. Single-crystal HgTe and segmented HgTe/Te nanowires have been grown, and the resistivity of the nanowires has been measured by conductive atomic force microscopy (AFM), where the AFM tip has been used as a mobile electrode.

The defect morphology in HgTe and CdHgTe was studied in (211)B-oriented layers grown in a 20°C temperature range around the optimal growth temperature. The density of defects varies strongly with the growth temperature. In HgTe, the shape of the microvoid defects is very sensitive to the growth temperature and can be used to determine the deviation from the optimal growth temperature. Using thermodynamical modeling, the optimal growth temperature for CdHgTe can then be calculated. We describe a mechanism for the formation of microvoids and needles which involves preferential surface diffusion of Te combined with an impurity or defect on the substrate. Microvoids on (111)B-oriented partially twinned HgTe layers were also studied. The microvoids in the twinned parts of the layer were found to be rotated 180 deg relative to the untwinned parts of the layer.

Item does not contain fulltext BACKGROUND AND AIMS: EUS-guided FNA or biopsy sampling is widely practiced. Optimal sonographic visualization of the needle is critical for image-guided interventions. Of the several commercially available needles, bench-top testing and direct comparison of these needles have not been done to reveal their inherent echogenicity. The aims are to provide bench-top data that can be used to guide clinical applications and to promote future device research and development. METHODS: Descriptive bench-top testing and comparison of 8 commonly used EUS-FNA needles (all size 22 gauge): SonoTip Pro Control (Medi-Globe); Expect Slimline (Boston Scientific); EchoTip, EchoTip Ultra, EchoTip ProCore High Definition (Cook Medical); ClearView (Conmed); EZ Shot 2 (Olympus); and BNX (Beacon Endoscopic), and 2 new prototype needles, SonoCoat (Medi-Globe), coated by echogenic polymers made by Encapson. Blinded evaluation of standardized and unedited videos by 43 EUS endoscopists and 17 radiologists specialized in GI US examination who were unfamiliar with EUS needle devices. RESULTS: There was no significant difference in the ratings and rankings of these needles between endosonographers and radiologists. Overall, 1 prototype needle was rated as the best, ranking 10% to 40% higher than all other needles (P < .01). Among the commercially available needles, the EchoTip Ultra needle and the ClearView needle were top choices. The EZ Shot 2 needle was ranked statistically lower than other needles (30%-75% worse, P < .001). CONCLUSIONS: All FNA needles have their inherent and different echogenicities, and these differences are similarly recognized by EUS endoscopists and radiologists. Needles with polymeric coating from the entire shaft to the needle tip may offer better echogenicity.

The fourth part of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Guidelines on Interventional Ultrasound describes general aspects of endoscopic ultrasound-guided diagnostic and therapeutic interventions and assesses the evidence for endoscopic ultrasound-guided sampling. Endoscopic ultrasound combines the most advanced high-resolution ultrasound imaging of lesions within the wall and in the vicinity of the gastrointestinal tract and safe and effective fine needle-based tissue acquisition from these lesions. The guideline addresses the indications, contraindications, techniques, adverse events, training and clinical impact of EUS-guided sampling. Advantages and drawbacks are weighed in comparison with image-guided percutaneous biopsy. Based on the most current evidence, clinical practice recommendations are given for crucial preconditions and steps of EUS-guided sampling as well as for safe performance. Additionally, the guideline deals with the principles and reliability of cytopathological reporting in endoscopic ultrasound-guided sampling (short version; the long version is published online).

no abstract available

HgTe nanowires nucleated by Au particles have been grown on Si and GaAs substrates by molecular beam epitaxy. The wires are polycrystalline. They evolve from crooked to straight during growth and have rounded to rectangular cross-sections. The widths are in the range 20–500 nm, with lengths up to 4 μm. The height of the nanowires is typically less than the width. The nanowires have been characterized by scanning electron microscopy, x-ray photoelectron spectroscopy, transmission electron microscopy and atomic force microscopy. The effects of substrate material, substrate preparation and growth conditions have been investigated.

Measurements are presented of the spectral response of MBE (molecular beam epitaxy)-grown, ion-milled, lateral photodiodes fabricated in the Hg1−xCdxTe material system with x≈0.31. The optical collection length is extracted from measurements taken from diodes of variable diameter. From the temperature dependence of the optical collection length, it is suggested that radiative recombination and Auger recombination processes determine the lifetime of the minority charge carriers.

CdxHg1−xTe layers with bandgap in the mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) regions were grown by molecular beam epitaxy, and one-dimensional (1D) and two-dimensional (2D) arrays of planar photodiodes were fabricated by ion milling of vacancy-doped layers. The grown layers have varying densities of needle-shaped structures on the surface. The needles are not associated with twins or dislocations in the layers, but could instead be due to (111) facets being reinforced by a preferential Te diffusion direction over steps on the surface. The needles do not seem to affect diode quality. 64 element 1D arrays of 26×26 μm2 or 26×56 μm2 diodes were processed, and zero-bias resistance-times-area values (R0A) at 77 K of 4×106 Ω cm2 at cutoff wavelength λCO=4.5 μm were measured, as well as high quantum efficiencies. To avoid creating a leakage current during ball-bonding to the 1D array diodes, a ZnS layer was deposited on top of the CdTe passivation layer, as well as extra electroplated Au on the bonding pads. The median measured noise equivalent temperature difference (NETD) on a LWIR array was 14 mK for the 42 operable diodes. 2D arrays showed reasonably good uniformity of R0A and zero-bias current (I0) values. The first 64×64 element 2D array of 16×16 μm2 MWIR diodes has been hybridized to read-out electronics and gave median NETD of 60 mK. Images from both a 1D and a 2D array are shown.

Imaging one-dimensional (1-D) and two-dimensional (2-D) arrays of mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) planar photodiodes were fabricated by ion milling of vacancy-doped molecular beam epitaxy CdxHg1−xTe layers. Sixty-four-element 1-D arrays of 26×26 µm2 or 26×56 µm2 diodes were processed. Zero-bias resistance-area values (R0A) at 77 K of 4×106 Θcm2 at cutoff wavelength λCO=4.5 µm were measured, as well as high quantum efficiencies. To avoid creating a leakage current during ball bonding to the 1-D array diodes, a ZnS layer was deposited on top of the CdTe passivation layer, as well as extra electroplated Au on the bonding pads. The best measured noise equivalent temperature difference (NETD) on a LWIR array was 8 mK, with a median of 14 mK for the 42 operable diodes. The best measured NETD on a MWIR array was 18 mK. Two-D arrays showed reasonably good uniformity of R0A and zero-bias current (I0) values. The first 64×64 element 2-D array of 16×16 µm2 MWIR diodes has been hybridized to read-out electronics and gave median NETD of 60 mK.

Background: Neoplasm seeding is a serious complication after liver metastases biopsy. Reported incidences vary between 10% and 19% for colorectal cancer (CRC) and are unknown for breast cancer (BC). The aim of this retrospective study was to determine the frequency of tumor seeding after ultrasound-guided percutaneous biopsy of CRC and BC liver metastases. Material and methods: Unselected liver biopsies performed in the period of 2005–2012 at our institution were extracted from the National Pathology Registry. Medical records including imaging from patients with biopsy-verified BC and CRC liver metastases were retrospectively reviewed. The endpoint was the development of abdominal wall recurrence following liver biopsy. Results: Of total 2981 biopsies we identified 278 patients with CRC and 155 patients with BC biopsy-verified liver metastases. During the median follow-up of 25 months after biopsy (range 3–253 months), no seeding was recorded in patients with BC. Within the median follow-up of 34 months (3–111 months), seeding was registered in 17/278 (6%) of patients with CRC; three patients of 278 (1%) had undoubtedly biopsy-related seeding, which became apparent six, nine, and 26 months after biopsy, respectively; and in nine patients (3%) seeding occurred due to either biopsy or other interventions; and five patients had seeding, which were assessed as a consequence of other invasive procedures than biopsies. The median overall survival of the 17 patients with seeding was 70 months compared to 39 months of patients without seeding. Conclusions: The results showed no seeding in BC patients. Seeding rate after biopsy in CRC patients is not negligible, however, without affecting outcome.

Planar mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) photodiodes were fabricated by ion milling molecular beam epitaxy (MBE) CdxHg1-xTe (CMT) layers with and without compositional grading in the layer. Linear arrays with 32 and 64 diodes, as well as test diodes of varying size, were fabricated. Good quantum efficiencies were measured, and MWIR diodes, with cutoff wavelength λco = 4.5 µm, had zero-bias resistance-area values (RoA) in excess of 1 × 107Ωcm2, whereas LWIR diodes with λco = 8.9-9.3 µm had RoA = 3 × 102Ωcm2 at 77 K. Comparison between a limited number of layers indicates that in layers with a gradient the RA values are a factor of ∼10 larger, and possibly more uniform, than in layers without a gradient.

A fast and non-destructive method for generating three-dimensional maps of the grain boundaries in undeformed polycrystals is presented. The method relies on tracking of micro-focused high-energy X-rays. It is verified by comparing an electron microscopy map of the orientations on the 2.5 × 2.5 mm surface of an aluminium polycrystal with tracking data produced at the 3DXRD microscope at the European Synchrotron Radiation Facility. The average difference in grain boundary position between the two techniques is 26 µm, comparable with the spatial resolution of the 3DXRD microscope. As another extension of the tracking concept, algorithms for determining the stress state of the individual grains are derived. As a case study, 3DXRD results are presented for the tensile deformation of a copper specimen. The strain tensor for one embedded grain is determined as a function of load. The accuracy on the strain is Δ∊ ≃ 10−4.

Arteriovenous (AV) malformations are rare and may occur at various locations, like in the brain, liver, lungs, or in the subcutaneous tissue. This case report describes an AV malformation from the right occipital artery. The value of combined B-mode ultrasonography and color Doppler mode imaging of masses in the neck region is discussed.

The present work reports macroscopic thermal mechanical and in-situ neutron diffraction measurements from 22.9 vol.%, 50.7 at.% Ni–Ti fiber actuated 6082-T6 aluminum matrix composite and 6082-T6 homogeneous aluminum control materials subjected to a room temperature 4% tensile elongation, a subsequent room temperature to 120°C unconstrained heating process, and a final 120°C tensile process. During the unconstrained room temperature to 120°C heating process, the composite exhibited a pronounced, nonlinear thermal contraction, while the homogeneous control exhibited the expected linear thermal expansion. The composite thermal contraction was clearly the result of a powerful shape memory response in the actuating NiTi fibers. The paper further presents a one-dimensional thermal strain, internal stress and fiber phase transformation composite model. Model parameters were identified from tests on extracted single fibers, calculations using these parameters quantitatively agree with experimental thermal mechanical and neutron diffraction measurements.

Residual lattice strains in the aluminium and SiC phases of F3S.20S extruded A359 20% SiC metal-matrix composite were measured by using neutron diffraction at room and elevated temperatures to monitor the effects of in situ uniaxial plastic deformations. The results are interpreted with reference to the thermomechanical history of the specimens. The compressive strain at yield due to thermal expansion mismatch strains and uniaxial deformation was found to be identical over the temperature range 100–250 °C. The separation of the aluminum compressive and tensile strain yield loci were found to be 4.5 × 10−4 at 50 °C, 4.1 × 10−4 at 100 °C and 2.5 × 10−4 at 250 °C. The temperature dependence of the separation of the loci was found to agree closely with the temperature dependence of the macroscopic flow stress.

Macrostrain variations in engineering components are frequently examined using neutron diffraction, at both reactors and pulsed sources. It is desirable to minimize the sampling volume in order to maximize the spatial resolution, although this increases the required measurement time. At reactors, macrostrain behavior is inferred from a single lattice reflection (deemed to be representative of the bulk response). At a pulsed source, a complete diffraction pattern is recorded and accordingly it is natural to fit the entire diffraction spectra using a Rietveld [J. Appl. Cryst. 2, 65 (1969)] refinement. This means that an idealized crystal structure is fit to the measured distorted crystal structure, which includes deviation of the measured lattice reflections from the ideal due to elastoplastic strain anisotropies, which are dependent on the particular lattice reflection (hkl) considered. We show that elastic macrostrains calculated from lattice parameter changes in Rietveld refinements (without accounting for hkl dependent anisotropies) are almost identical to the bulk elastic response and are comparable to the response obtained from a single lattice reflection typically used by practitioners at a steady state source. Moreover good refinements on the complete pattern are obtained with short measurement times compared to what is required for good statistics for single reflections. By incorporating a description of the elastic strain anisotropy expected in cubic materials into the Rietveld code, an empirical prediction of plastic strain history is possible. The validity of these arguments is demonstrated by analysis of a uniaxial tensile load test and a reanalysis of previously reported data taken on a deformed stainless steel ring. The plastic strain predictions compare favorably with a finite element model.

Copyright (c) 1997 Elsevier Science Ireland Ltd. All rights reserved. Objective: Breast ultrasound and US-guided interventional procedures of the breast are increasingly being applied and integrated in the diagnostic work-up and management of breast patients. The aim of the study was to assess the reliability of ultrasound-guided (US-guided) needle core biopsy of palpable breast masses with a 1.2 mm needle (18 gauge) in a fully automated firing device as an alternative to the existing surgical routine, i.e. surgical excision or palpation-guided Tru-Cut biopsy with a 2.0 mm needle (14 gauge) in a semi-automated device. Method: US-guided biopsy of palpable breast masses was prospectively, consecutively and openly compared to open surgical biopsy in a design closely connected to the routine diagnostic work-up of these patients. Results: 106 Patients with a palpable mass in one of their breasts were included in this study. The final diagnosis was the histological result of the open surgical biopsies, which were: 49 malignant lesions, 14 fibroadenomas, and 43 cases of fibrocystic disease. Forty-six malignant tumors were detectable ultrasonically and US-guided biopsy was performed, yielding adequate and correctly positive diagnoses in 41 cases (89%). Three US-guided samples were adequate for diagnosis but yielded a false-negative result. Two samples were excessively fragmented and thus inadequate for diagnosis. All 14 fibroadenomas were correctly diagnosed ultrasonically and US-guided sampling yielded a correct diagnosis in all but one case which was inadequate. The remaining 43 cases showed no abnormality on the sonogram and open biopsy yielded fibrocystic disease. Conclusion: US-guided biopsy of palpable breast masses can obviate open surgical biopsy whenever a mass is ultrasonically visible and it is strongly advocated to implement the procedure in the diagnostic work-up of these patients. © 1997 Elsevier Science Ireland Ltd.

Rationale and Objectives. Radiofrequency (RF) tissue ablation with a cooled needle electrode (probe) can produce large lesions. By using this technique on ex vivo calf livers, the authors evaluated the role of ultrasound (US), dose response, and temperature course with time. Methods. RF ablation was produced with a 14-gauge probe with a 2-cm exposed tip. The lesions were examined with US and macroscopically after various treatment durations. Tissue temperature was measured with thermosensors inserted 1, 2, and 3 cm from the probe. Results. Before treatment the tip of the probe was easy to visualize with US, but during treatment microbubbles obscured the lesion and probe. After treatment, the lesions appeared hypoechoic. Lesion size was underestimated based on US findings. Lesion size was logarithmically correlated to treatment duration. Lesion temperature increased at an increased rate with higher wattage applied and with decreased distance from the probe. Conclusion. US is useful for probe placement before treatment and might be of value after treatment. Lesion size increases reproducibly with treatment duration.

Composite samples are produced by casting copper around a long, single-fibre inclusion of tungsten. Samples are subsequently wire-drawn to reduce the grain size. Using high energy X-ray diffraction, the spatial distribution of residual lattice strains is mapped, showing large strain gradients between the sample surface and fibre matrix interface in samples with different thermal histories. The large strain gradients are primarily attributed to inhomogeneous deformation caused by the presence of the fibre during drawing. Distinct non-linearities in the strain gradients are attributed to the development of strong radial texture variations, and annealing at 300°C is found to significantly reduce the magnitude of the strain gradients.

A retrospective study was designed to compare the diagnostic yield of US-guided (FNAB) fine needle aspiration biopsy (N = 92) from clearly defined hepatic lesions with diameters of 2 cm or larger, when one, two or three needle passes were performed. No significant diagnostic loss was detected when the number of needle passes was reduced from three to two (Sensitivity = 0.985, Specificity = 1.0, Pos. predictive value (PPV) = 1.0, Neg. predictive value (NPV) = 0.81). However, an unacceptable diagnostic loss was seen when only one needle pass was evaluated (Sensitivity = 0.81, Specificity = 1.0, PPV = 1.0, NPV = 0.69). We conclude that two needle passes can be recommended as a standard procedure for US-guided fine needle aspiration biopsy from hepatic lesions larger than 2 cm in diameter provided the procedure is performed routinely.

Rationale and Objectives. I developed and tested a cooled needle electrode (CNE) for radiofrequency (RF) tissue ablation in vitro. Methods. A 2-mm needle electrode with two lumina for internal water perfusion and irrigation of the needle tip and a conventional needle electrode were tested in ex vivo calf liver during different levels of output power (wattage). RF lesions produced by the two needle types were further evaluated with a thermal camera. Results. When the CNE was used, a significant increase in the duration of ablation was observed, which caused a significant increase in delivered energy and lesion size when compared with the conventional needle electrode. The largest lesion produced with the CNE was almost spherical and measured 41 × 37 mm (longitudinal × transverse). The cooling effect was reflected in the image obtained with the thermal camera. Conclusion. This technique produced very large lesions compared with conventional methods and may have a role in many different kinds of RF needle ablation.

SummaryIn an animal study, we have tested a special loop electrode for ultrasound-guided percutaneous interstitial tissue ablation using monopolar radiofrequency (RF) electrosurgery. The loop electrode with a radius of 1 cm was inserted into calf livers via an insulated introducer cannula. Monopolar RF current in the cut mode was applied to the loop electrode which was rotated a full turn. During this, a lesion was cut off interstitially. In three sedated calves a total of seven liver lesions were made percutaneously or during laparotomy. The procedure was guided and monitored by ultrasono-graphy including colour Doppler imaging. Autopsy was performed on day 0 or day 8 post treatment and included gross sectional examination and microscopic evaluation (light microscopy and electron microscopy). In the first animal, the lesions were incomplete because of insufficient voltage setting. In the second and third animal, however, four spherical lesions with a diameter of 2 cm were cut off without clinical complic...

Objective: The purpose of the study was to assess the value of ultrasound in detecting focal lesions of the breast, in differentiating between benign and malignant lesions and in detecting axillary dissemination of a malignant disease, and to assess the clinical impact of the implementation of breast ultrasound in symptomatic patients. Materials and methods: A prospective, consecutive, blinded study was conducted, comparing the results of the ultrasonic examination of the breast with those of mammography. One hundred and ninety nine patients with a mean age of 48 years (range: 19–80 years) were examined according to a strict methodological design. All these patients were referred for X-ray mammography as they were suspected of having a malignant disease of the breast; they were all affiliated to the general surgery ward (responsible for breast surgery). Specified analytic criteria (tumor shape and margins, architectural distortion and retrotumoral acoustic effect) were used to assess the findings. Results: There were 28 cancers. Ultrasound detected 27, whereas mammography detected 22. McNemar's test yielded a P value of 0.037 for patients with malignant disease, thereby showing a tendency towards breast ultrasound being a better diagnostic method than X-ray mammography. The same tendency applies to the benign findings. Conclusion: In this study, breast ultrasound had better results than mammography in detecting focal lesions, in differentiating the nature of the lesions, as well as detecting dissemination of malignant disease. A more liberal use of breast ultrasound is advocated.

Residual stresses in an offshore weld may affect the fatigue life of the structure, and should hence be included in calculations of fatigue crack propagation and fatigue lives. In the present investigation neutron diffraction is used as a non-destructive technique for the evaluation of through thickness variations of residual strains in welded test samples of steel plates. The neutron diffraction strain measurements show relatively high residual strains reaching + 1 × 10−3 near the outer surfaces and −4 × 10−4 near the centre of the plates. A simplified strain/stress conversion indicates that the highest residual stress exceeds approximately 50% of the material yield stress of σy ≈ 400 MPa.

Percutaneous gastrostomy, utilizing a dedicated catheterization kit, with a combination of ultrasonographic (US) and fluoroscopic guidance, was carried out in 27 patients. The main indication for gastrostomy was the need for nutritional support in malignant esophageal stricture. After distending the stomach with water via a nasogastric tube, the gastric antrum was punctured under US guidance and a guide wire was inserted, followed by fluoroscopically guided tract dilatation and insertion of a 2.5-mm Cope-loop catheter. In all patients but one (96%) the procedure was successfully completed in one or 2 attempts. Two complications occurred: one case of a small subcutaneous abscess near the puncture site, and one late incident of dislodgement of a catheter without string-loop fixation, which had been inserted at a catheter exchange after 6 weeks. Percutaneous gastrostomy guided by US and fluoroscopy is a safe and efficacious alternative to endoscopic and surgical gastrostomy.

Purpose: A new method for internal drainage of malignant ascites is presented in 5 patients with symptomatic malignant ascites. Material and Methods: US-guided percutaneous gastrostomy and paracentesis were performed using the Seldinger technique. A 2.5-mm Cope-loop catheter was inserted in the fluid-filled stomach. In the lower abdomen the proximal part of a Denver peritoneo—venous shunt was introduced after dilation up to 4.8 mm. The pump chamber was sutured to the skin. The distal part of the Denver shunt was cut a few cm from the pump chamber and connected to the gastrostomy catheter. When pumping, ascites is shunted to the stomach lumen. Results: The insertion presented no complications, and all shunt systems initially functioned well. However, the shunts had to be removed within the first 2 weeks because of mechanical problems such as clotting, leakage, and peritoneal septum formation. No infections were reported. Conclusion: The peritoneo—gastric shunt may present a therapeutic alternative in selected patients, but the mechanical problems have first to be solved.

Ultrasound (US)-guided interstitial hyperthermia performed with the neodymium yttrium aluminum garnet laser with a diffuser tip involves placement of a laser fiber in solid tissue followed by irradiation from within the center of the tumor to be treated. The authors previously described the development of a US-guided technique that permits simultaneous interstitial laser irradiation and temperature measurements, with real-time US monitoring. With the use of a dedicated diffuser tip modification of the bare laser fiber, it has proved possible to produce spherical coagulations with a diameter comparable to that of liver metastases of clinical relevance. This technique was used in 11 patients with 16 colorectal liver metastases, 12 of which were radically ablated. Real-time US and interstitial temperature monitoring during treatment had a positive predictive value of 86% and negative predictive value of 100% in judging the final result. The technique is feasible, effective, and safe, but the effect on patient survival must be tested in future randomized clinical studies.

Residual stresses have long been of concern to engineers and materials scientists, as these stresses can have a strong effect on the performance of materials and hence on the structures in which these materials are used. Some techniques do exist for the evaluation of residual stresses, e.g. destructive hole drilling techniques and techniques based on ultrasonic measurements. However, so far the majority of residual stress measurements have been done using the well established X-ray diffraction technique. This technique is widely used for studies of surface residual stresses, and by applying a destructive etching or sectioning technique, the method can also give information about the residual stress state below the surface of structures.

Using a duplex Doppler technique, we investigated the effect of low doses of secretin on the portal blood flow. In eight healthy volunteers successive intravenous secretin infusions of 0, 8, and 32 pmol x kg-1 x h-1 resulted in proportional increases in plasma secretin levels. The portal venous flow, however, was unaffected. A bolus injection of 930 pmol of secretin caused plasma secretin levels to increase 100-fold, whereas blood flow in the portal vein increased only by a factor three. This suggests that secretin in the present dose range is of no quantitative importance as a regulator of portal venous flow under physiologic conditions.

(1992). Ultrasound Guided Nephrostomy Utilizing a One-Step Balloon Catheter. Acta Radiologica: Vol. 33, No. 3, pp. 279-281.