Magnetic Needle Research Articles

Magnetic resonance imaging-guided core needle biopsy and needle localized excision of occult breast lesions

Background: Breast magnetic resonance imaging (MRI) has been reported to be twice as sensitive and three times more specific in detecting breast cancer. We report a series of MRI-guided stereotactic breast biopsies (SCNBB) and needle localized breast biopsies (NLBB) to evaluate MRI as a localization tool. Methods: Forty-one breast lesions were identified in 39 patients who subsequently had SCNBB or NLBB. Suspicious areas of enhancement were stereotactically biopsied with 16-G core biopsy needles or localized with 22-G wires for excision under laser guidance. Results: Forty-one breast lesions were identified from 1,292 breast MRIs. SCNBB identified three malignancies and two areas of atypia. Two additional cancers were found after NLBB. In patients having NLBB alone, five cancers and two areas of atypia were identified. Conclusions: In this initial series, breast MRI-guided SCNBB and NLBB were valuable tools in the management of patients with suspicious abnormalities seen only on MRI.

Relation Between Shear Viscosity and Morphology in Lung Surfactant Monolayer

The primary function of lung surfactant monolayers (LS) is to control and reduce surface tension in the lung permitting easy breathing. to do this, the monolayer must maintain coverage of the entire lung surface during the rapid surface area changes which accompany breathing. We use a magnetic needle viscometer and optical microscopy to determine the relationship between monolayer shear viscosity, which controls its two-dimensional flow properties, and synthetic lung surfactant composition. We show that, within a specific range, palmitic acid interacts with DPPC/POPG to make lung surfactant rigid at low surface tension (or high surface pressure) and fluid at high surface tension. This enables the monolayer to attain near zero surface tensions during compression yet respread easily at high surface tension More palmitic acid makes the monolayer more rigid and eventually increases the collapse surface tension while reducing the readsorption rate at high surface tension.

Um experimento de oscilador forçado amortecido

Este trabalho apresenta um experimento apropriado para as aulas de laboratório que são normalmente oferecidas em cursos de graduação. Este experimento está baseado em oscilações forçadas amortecidas de uma agulha magnética e permite a observação do fenômeno de ressonância, que ocorre quando a freqüência do campo magnético dependente do tempo coincide com a freqüência de oscilações livres da agulha de uma bússola, que por sua vez depende da magnetização e do momento de inércia da agulha. As oscilações da agulha foram monitoradas com uma sonda Hall e um microcomputador, e os resultados experimentais foram comparados com a teoria através da análise de Fourier dos dados. Estes resultados apresentaram boa concordância com as previsões teóricas.

Romagnosi e la scoperta dell’elettromagnetismo

In 1802 Gian Domenico Romagnosi observed in Trento the deviation of the magnetic needle induced by an electric current. Did he anticipate the most famous Oersted’s experiment of 1820? Did he ever claim priority in the discovery of electromagnetism? Who was aware of his results? The historical debate on Romagnosi’s experiment is reviewed on the basis of documents so far ignored in the literature.

Symmetry in electromagnetism—A new magnetic needle

Students frequently are introduced to Oersted’s experiment by deflecting a plotting compass beneath a straight current-carrying conductor. Thereafter, electromagnets, electric bells, relays, and motors are explored. When attention is turned to electromagnetic induction, the usual setup involves thrusting a straight wire between the jaws of a powerful horseshoe magnet. To help underline the symmetry involved, we have developed a stronger magnetic needle and outline here how we use it in our classes.

307 磁気コンパスの歴史 : 指南針について(機械技術史・工学史)

In this paper, SHINANSHIN which is a initialform of the magnetic compass is reported. SHINANSHIN is the south seeking needle. First this magnetic needle was made by natural magnet. Afterwards, used magnetic needle changed to the magnet which was artifical from natural magnet. These processes are described from the discovery that has the property in which the magnet points to the south. And, the process of the chnge of the south seeking needle to the magnetic compass is also described.

Correlation of Fine Needle Aspiration Biopsy and Dynamic Contrast-Enhanced 3D Magnetic

To correlate and assess the utility of dynamic contrast-enhanced three-dimensional gadolinium-enhanced magnetic resonance imaging (Gd-3DMRI) and fine needle aspiration biopsy (FNAB) findings in patients with suspected breast disease. Beginning in 1993, all patients who underwent percutaneous FNAB of the breast and had concurrent Gd-3DMRI evaluation of the breast were selected for this study. Findings for FNAB and Gd-3DMRI were stratified into two categories, positive and negative. Subsequent clinical management decisions, which included surgical intervention and/or clinical follow-up, were recorded for all patients. There were 69 FNABs in 59 patients with corresponding Gd-3DMRI evaluation. A positive result by both FNAB and Gd-3DMRI was found in 15 of 18 malignant cases. FNAB missed one case, and Gd-3DMRI missed two, and each of these was thought to be technical. Combining the methods yielded 100% sensitivity. False positive results on Gd-3DMRI (17 cases) were all confirmed to be benign by FNAB and subsequent tissue evaluation. All 32 cases with combined negative results by FNAB and Gd-3DMRI demonstrated a benign process, yielding a specificity of 100% (32/32). Our combined testing modalities showed a high degree of specificity and good sensitivity. FNAB used with dynamic contrast-enhanced Gd-3DMRI can contribute valuable information for physicians treating patients with suspected breast abnormalities.

The experiments of Biot and Savart concerning the force exerted by a current on a magnetic needle

Francois Arago brought the news of Oersted’s discovery of the effect of a current-carrying wire on a magnet to Paris on September 4, 1820. André-Marie Ampère and the team of Jean-Baptiste Biot and Félix Savart quickly set to work to establish a quantitative law for this effect. Their approaches were quite different. This paper describes the experiments of Biot and Savart and their results. It also briefly discusses the approach of André-Marie Ampère, who coined the name “electrodynamics” and whose fundamental formula gave the force between two infinitesimal current elements. Ampere’s formula fell into disuse after the advent of Maxwell’s field approach. Biot and Savart’s experimental law, in the modern form of the differential magnetic field due to a current element, became the standard starting point for calculating the magnetic field due to steady currents.

Diagnosis of 26 small hepatocellular carcinoma using incremental dynamic computed tomography.

Hepatocellular carcinoma (HCC) is usually visualized as high density area in early phase of an incremental dynamic computed tomography (ID-CT). Small HCC nodules less than 2 cm in diameter are sometimes, however, showing no contrast enhancement. We examined 26 HCC nodules less than 2 cm in diameter by ID-CT. All HCC nodules examined were originally detected by ultrasonography and diagnosed by fine needle biopsy in histology. We studied the sensitivity of ID-CT in detecting HCC nodules and a possible association between a presence or absence of contrast enhancement and the degree of cell differentiation of HCC nodules. Of the 26 HCC nodules, 22 (84.6%) were detected by ID-CT. Of the 22 detected nodules, 7 were depicted as high density area in early phase of ID-CT, and 5 were moderately differentiated HCC and the other 2 were poorly differentiated HCC in histology. Twelve nodules were low density area in early phase of ID-CT, and all of them were well-differentiated HCC. The other 3 nodules, which were isodense in early phase, were depicted as low density area in late phase, and 2 were well-differentiated HCC and other was moderately differentiated HCC. In this study, most of small and well-differentiated HCC nodules less than 2 cm in diameter showed no contrast enhancement in early phase of ID-CT. Therefore, when ID-CT of intrahepatic nodules less than 2 cm shows low density in early phase without contrast enhancement, well-differentiated HCC are most suspected, and further examinations such as magnetic resonance imaging and needle biopsy are needed.

A remark on Dirac’s magnetic monopoles

The only reasonable magnetic «monopoles» are the poles of very long and very thin magnetic needles.

Emission of extremely strong magnetic fields from the head and whole body during oriental breathing exercises.

This article reports the result of an experiment that was designed to measure the biomagnetic field emanating from two individuals who were practising traditional Oriental Qi Gong breathing exercises. The biomagnetic field was measured with differential coils wound 80,000 turns, a magnetic needle compass and a digital electromagnetic wave detection device. It was found that an extremely strong magnetic field was emitted from the two individuals. One subject emitted a magnetic field at the level of 200-300 mT (2-3 mGauss) and the other at 0.13 mT (1.3 mGauss). In both cases, moreover, the magnetic needle compass rotated 30 degrees (this was tested 32 times). When the rotation of the needle occurred, a reproducible magnetic field of 800-1500 mT (8-15 mGauss) was indicated on the digital measuring device (this was tested 12 times). It is concluded that traditional Oriental Qi Gong breathing appears to stimulate an unusually large biomagnetic field emission.

White Heat: People and Technology by Carroll Pursell

Book Reviews White Heat: People and Technology. By Carroll Pursell. Berkeley and Los Angeles: University of California Press, 1994. Pp. 224; illustrations, notes, index. $18.00 (paper). If we have a clear view of values and power relationships in society, “we can deconstruct our .. . technologies to discover the often hidden ways in which their apparent neutrality masks codes of privilege and meaning.” With that comment (p. 29), Carroll Pursell proceeds to deconstruct industry, weapons, sanitation, scientific research, and in­ formation technology in a style well adapted for reading by a wide audience, making many serious and stimulating points on the way. The process of deconstruction exposes myths about the supposed “irresistible logic” (p. 39) of invention and about the tendency always to overestimate the revolutionary nature of technological change (p. 216). It shows how a “veil of ‘science’” could disguise the exercise of power by managers who adopted Taylorism and indicates that the “temptation to use technology in order to avoid facing questions of social justice was as old as the American republic” (p. 104). Social justice then crops up more specifically in the context of information technology, where the Office of Technology Assessment has warned how “the gap” between those who can access services and those who cannot is likely to increase (p. 203). Near the end of the book is some discussion of Western attitudes to Japan. Its implication is that, having habitually understood the history of technology in terms of Western achievement, rather than recognizing the dialogue with other cultures that actually occurred, we are now seriously ill-prepared for the technological successes of Japan and unwilling to learn the lessons that might be drawn. One lesson, for example, is that although information technology is likely to be associated with an increase in social inequalities in Western countries, this may not happen in Japan, which seems set to remain the most egalitarian of the industrialized countries. Privilege is en­ coded notjust in the technological hardware but also in the different institutions and the different versions of capitalism that are to be found in the West and in Japan. Deconstruction of the meaning of technology sometimes leads to surprising conclusions. Nineteenth-century sewers were the seat of dark threats, with their role in the spread of disease still not well Permission to reprint a review printed in this section may be obtained only from the reviewer. 680 TECHNOLOGY AND CULTURE Book Reviews 681 understood, and “Just as female nature was always a threat to male structure ... so the sewers needed to be brought under control” by the rational, masculine order of the engineer (pp. 186-87). The eight chapters of the book, it should be explained, were written as “a companion to” but “not a substitute for” an eight-part television series. The book can be read quite independently, however, and worked well for me without seeing its television counterpart. Pursell says that he has felt free in this context to present “a collage rather than a linear narrative” (p. 7), and like a television presenter, he sometimes glides swiftly from one topic to another, leaving a trail of non sequiturs. This does not lead to serious problems, except perhaps in a chapter on time, high-speed photography, DNA, digital imaging, and the symbolism of staircases. One error in this chapter is the state­ ment that “invention of the electric telegraph by Samuel F. B. Morse in the United States led to its use in 1837 on the London and North Western Railway” (p. 70). In fact, the railroad telegraph referred to had been devised by William F. Cooke and Charles Wheatstone with­ out knowledge of Morse’s invention. They used a different system, dependent on the movement of magnetic needles, to give a visual signal to the person receiving the message. This and Morse’s tele­ graph were simultaneous but independent inventions, a full discus­ sion of which would have to mention Joseph Henry also. This is a generously illustrated volume which was put together by BBC Books, but the British illustrations do not always match the American examples quoted in the text, and some are quite superflu­ ous. Even so, it is a very effective popularization...

Gender and Technology in the Making by Cynthia Cockburn, Susan Ormrod, and: Bringing Technology Home: Gender and Technology in a Changing Europe ed. by Cynthia Cockburn, Ruža Fürst-Dilić

TECHNOLOGY AND CULTURE Book Reviews 681 understood, and “Just as female nature was always a threat to male structure ... so the sewers needed to be brought under control” by the rational, masculine order of the engineer (pp. 186-87). The eight chapters of the book, it should be explained, were written as “a companion to” but “not a substitute for” an eight-part television series. The book can be read quite independently, however, and worked well for me without seeing its television counterpart. Pursell says that he has felt free in this context to present “a collage rather than a linear narrative” (p. 7), and like a television presenter, he sometimes glides swiftly from one topic to another, leaving a trail of non sequiturs. This does not lead to serious problems, except perhaps in a chapter on time, high-speed photography, DNA, digital imaging, and the symbolism of staircases. One error in this chapter is the state­ ment that “invention of the electric telegraph by Samuel F. B. Morse in the United States led to its use in 1837 on the London and North Western Railway” (p. 70). In fact, the railroad telegraph referred to had been devised by William F. Cooke and Charles Wheatstone with­ out knowledge of Morse’s invention. They used a different system, dependent on the movement of magnetic needles, to give a visual signal to the person receiving the message. This and Morse’s tele­ graph were simultaneous but independent inventions, a full discus­ sion of which would have to mention Joseph Henry also. This is a generously illustrated volume which was put together by BBC Books, but the British illustrations do not always match the American examples quoted in the text, and some are quite superflu­ ous. Even so, it is a very effective popularization and could be used with students as an introduction to important issues which many find difficult. The main drawback when used for that purpose would be the lack of a bibliography to make a clearer connection than is offered by the footnotes with the more substantial books in the field and to show how gaps in the relatively brief text might be filled. Arnold Pacey Mr. Pacey is a part-time tutor in the history of technology for the Open University and is also author of Technology in World Civilization (Cambridge, Mass., 1990). Gender and Technology in the Making. By Cynthia Cockburn and Susan Ormrod. Thousand Oaks, Calif.: Sage, 1993. Pp. ix+185; refer­ ences, index. $55.00 (cloth); $21.95 (paper). Bringing Technology Home: Gender and Technology in a Changing Europe. Edited by Cynthia Cockburn and Ruza Furst-Dilic. Buckingham: Open University Press, 1994. Pp. x+187; bibliography, index. $79.00 (cloth); $27.50 (paper). These two books stem from a five-year project (1988-92) initiated by the European Centre for the Co-ordination of Research and Docu­ 682 Book Reviews TECHNOLOGY AND CULTURE mentation in the Social Sciences (the Vienna Centre) to carry out cross-cultural research on “the impact of changing technology on gender relations.” Reformulating this charge to “the mutual reshap­ ing of technology and gender relations” (p. 3), the invited researchers chose to focus on new or innovative domestic technologies, tracing their life trajectories through key stages from design to use. Gender and Technology in the Making by Cynthia Cockburn and Susan Ormrod does this for the microwave oven in Britain. Bringing Technology Home is a collection of studies from eight countries—Finland, England, Greece, France, Norway, Russia, Spain, and the former Yugoslavia— and includes a vacuum-cleaning system, the microwave, computer­ ized banking, a “food robot,” a videotext telephone, automated ho­ siery production, washing machines, and a “smart house.” Bringing Technology Home was edited by Cockburn, project coordinator, and Ruza Fiirst Dilic of the former Yugoslavia. The research was situated in social constructivism and in the actor-network approach of Michel Calion and Bruno Latour for technology, and in the feminist litera­ ture on gender, especially as related to work. The method relied mainly on interviews and participant observation. Viewing gender and technology as interactive processes, the authors aimed to show how gender, “one of the major structures of the social order...

Original Articles: Prostate Cancer: The Use and Accuracy of Cross-Sectional Imaging and Fine Needle Aspiration Cytology for Detection of Pelvic Lymph Node Metastases Before Radical Prostatectomy

The role of cross-sectional pelvic imaging with computerized tomography or magnetic resonance imaging and fine needle aspiration in the assessment of pelvic lymph nodes in patients with prostate cancer is undefined. To address this issue we used formal decision analysis, comparing an imaging arm to a no imaging arm. Patient utility values were calculated, and test parameters and complication rates were extracted from the literature. Imaging was superior to no imaging only when the pretest probability of pelvic lymph node metastases was high. The most important parameter was the sensitivity of cross-sectional imaging for lymphadenopathy. When the sensitivity was 36%, which was the baseline figure derived from the literature, the probability of lymph node metastases required for imaging to be beneficial overall was 32%. We also performed a retrospective review of magnetic resonance imaging examinations at our institution in 174 patients with newly diagnosed prostate cancer and pathological confirmation of nodal status. The sensitivity for detecting nodal metastases was 25%. With this figure, the estimated probability of nodal metastases required to make imaging beneficial would be 45%, which is possible to achieve with highly selective clinical criteria. With a policy of imaging only in select patients the marginal cost is $794 per patient benefited (aborted radical prostatectomy because of nodal metastases detected with fine needle aspiration) compared to $50,661 per patient benefited if all patients are imaged. Thus, cross-sectional pelvic imaging before radical prostatectomy, solely for the purpose of detecting pelvic lymph node metastases, is not justified routinely. However, it is worthwhile on the basis of patient use values and cost-effectiveness in a select group of patients at high risk for nodal metastases.

Prototype breast coil for MR-guided needle localization.

Evaluation of breast lesions detected by MR alone is a problem: Preoperative MR-guided localization is difficult, since the breast is not accessible by a needle within the breast coil. Magnetic resonance-guided core biopsy and needle aspiration are impossible. Together with Siemens Erlangen, a prototype localization breast coil has been developed and tested. The device consists of a circular polarized coil, which contains two plates for mediolateral breast compression. They are perforated with numerous holes and thus allow access to the breast from both sides. By means of bushings, which fit into the holes, sterile needle insertion in a horizontal path is possible. So far, precise needle insertion has been possible in 10 of 11 lesions, allowing exact needle insertion into 5 invasive carcinomas (1 MR-detected), 1 MR-detected additional focus, 2 in situ carcinomas (1 MR-detected), and 3 benign lesions. Our studies show that MR-guided needle localization is possible.

Comparison of magnetic coil stimulation and needle electrical stimulation in the diagnosis of lumbosacral radiculopathy

Electrical stimulation (ES) of lumbosacral nerve roots using a needle electrode inserted to the laminar level at the midline of Th12-L1 or L1–2 intervertebral interspace, was compared with magnetic stimulation using a 9-cm diameter coil (MGS) at the L3–4 or L4–5 spine levels, Compound muscle action potentials (CMAP) were superficially recorded from homologous muscles in both sides in 15 normal control subjects and in 20 patients with lumbosacral radiculopathy. Soleus muscles were used for S1, tibialis anterior (TA) for L5, and rectus femoris (RF) muscles for L4 roots. According to the clinical or radiological diagnosis (CAT, MRI and/or myelography) conventional needle EMG was capable to localise the root lesion in 16 of 20 patients (80%) and ES localised the root involvement in 18 of 20 patients (90%); the diagnostic value of MCS was lower, about 65% (13 of 20 patients). Although ES is uncomfortable and invasive, it is superior to needle EMG in localising unilateral or multiple lumbosacral root involvement. At present, MCS is not suitable for the diagnosis of lumbar radiculopathy.

Incidentalomas of the adrenal gland: 36 operated patients and review of literature.

Incidental discovery of an adrenal mass during radiologic examinations is common. Several recommendations have been made for the management of so-called incidentalomas. It has become clear that not all incidentalomas should be operated, but the criteria for nonoperative treatment have been under continuous debate. In this study 36 operated incidentalomas are presented, and the indications for operative treatment are discussed with a review of the recent literature on the subject. Four pheochromocytomas and three hormonally active cortical adenomas, two producing cortisol and one androgens, were found. In this series there were no malignancies. The operation could have been avoided in most cases, and patients could have been followed up with repeated radiologic examinations. It is suggested that masses smaller than 6 cm in diameter be followed radiologically after 3, 9, and 18 months. Masses between 3 and 6 cm could be further examined using magnetic resonance imaging and fine needle aspiration and then operated if features suggestive of malignancy are found. Masses larger than 6 cm in diameter should be treated operatively.

Magnetic inclinatory needles: approved by the Royal Society?

In 1674 Charles II appointed a Commission to examine the hitherto closely guarded and long standing claim of Henry Bond, to have discovered a means of calculating longitude at sea from observations of magnetic variation and inclination. With the single exception of the King’s Master of Mechanicks, the inventive virtuoso Sir Samuel Morland, the six members of the Commission were all Fellows of the Royal Society. It was not, however, a Royal Society committee. Morland was responsible for calling the members together, though it was the diligent Royal Chaplain, John Pell (F. R. S. 1660), who ensured that the Commission prosecuted the investigation of Bond’s proposals. An unnoticed aspect of the affair is the use of the Royal Society’s name by Henry Bond and the instrument maker Henry Wynne to imply approval of the longitude hypothesis and the artifact respectively. This situation indicates that two London mathematical practitioners were of the view that, within two decades of its foundation, the Royal Society was widely accepted as a disinterested judge of scientific quality, and worth using to convince others of the validity of an argument or the superiority of a product.

On the magnetostatic energy of uniformly magnetized needles

Closed analytic formulae are obtained for the magnetostatic snergy of uniformly magnetized needles of rectangular cross-section. It is shown that for arrays of needles with sufficient symmetry the magnetostatic energy takes a very simple form.

Magnetic Resonance Imaging-Guided Fine Needle Aspiration for the Diagnosis of Skull Base Lesions

Magnetic resonance imaging (MRI)-guided fine needle aspiration was used to obtain tissue from lesions of the skull base for cytologic diagnoses in 14 patients. Our technique utilized a guiding system to enable three-dimensional orientation in a two-dimensional scan and a high nickel content 22 gauge needle to minimize significantly MRI artifact. Needle access to the skull base was provided through a subzygomatic or retromandibular approach. In seven of nine cases an accurate diagnosis was established by this technique and later confirmed by surgical exploration and histologic analysis. Failure to obtain a representative specimen from the lesion occurred in one case and difficulty in interpreting the cytologic features of the tissue was encountered in another case. The indications, limitations, and technical details of the procedure are described.