WorldWideScience

Sample records for follow-up digital subtraction

  1. Follow-up of in situ vein femoral-to-popliteal bypass grafts with intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Hemingway, A.P.; Hartnell, G.G.; Smith, J.

    1986-01-01

    The detection of early strictures or occlusion of in situ vein (femoral to popliteal) grafts allows the possibility of surgical or radiological intervention to preserve graft function. Twenty patients have been followed up prospectively with intravenous digital subtraction angiography at 3-month intervals after surgery. Contrast medium is injected via a centrally placed catheter, and five over-lapping positions are examined using a 14-inch intensifier. An average total of 175-200 ml of contrast medium has been given. In all cases it has been possible to visualize the entire graft, the distal anastomoses, and the run-off. In four patients early stenoses have been diagnosed. Three have been treated by percutaneous transluminal angioplasty and one surgically, all with a successful outcome

  2. Follow-up after embolization of ruptured intracranial aneurysms: a prospective comparison of two-dimensional digital subtraction angiography, three-dimensional digital subtraction angiography, and time-of-flight magnetic resonance angiography.

    Science.gov (United States)

    Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

    2012-11-01

    To prospectively compare of the diagnostic value of digital subtraction angiography (DSA) and time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. Seventy-two consecutive patients were examined 3 months after the embolization. The index tests included: two-dimensional DSA (2D-DSA), three-dimensional DSA (3D-DSA), and TOF-MRA. The reference test was a retrospective consensus between 2D-DSA images, 3D-DSA images, and source rotational DSA images. The evaluation included: detection of the residual flow, quantification of the flow, and validity of the decision regarding retreatment. Intraobserver agreement and interobserver agreement were determined. The sensitivity and specificity of residual flow detection ranged from 84.6 % (2D-DSA and TOF-MRA) to 92.3 % (3D-DSA) and from 91.3 % (TOF-MRA) to 97.8 % (3D-DSA), respectively. The accuracy of occlusion degree evaluation ranged from 0.78 (2D-DSA) to 0.92 (3D-DSA, Cohen's kappa). The 2D-DSA method presented lower performance in the decision on retreatment than 3D-DSA (P < 0.05, ROC analysis). The intraobserver agreement was very good for all techniques (κ = 0.80-0.97). The interobserver agreement was moderate for TOF-MRA and very good for 2D-DSA and 3D-DSA (κ = 0.72-0.94). Considering the invasiveness of DSA and the minor difference in the diagnostic performance between 3D-DSA and TOF-MRA, the latter method should be the first-line modality for follow-up after aneurysm embolization.

  3. Follow-up after embolization of ruptured intracranial aneurysms: A prospective comparison of two-dimensional digital subtraction angiography, three-dimensional digital subtraction angiography, and time-of-flight magnetic resonance angiography

    International Nuclear Information System (INIS)

    Serafin, Zbigniew; Strzesniewski, Piotr; Lasek, Wladyslaw; Beuth, Wojciech

    2012-01-01

    To prospectively compare of the diagnostic value of digital subtraction angiography (DSA) and time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. Seventy-two consecutive patients were examined 3 months after the embolization. The index tests included: two-dimensional DSA (2D-DSA), three-dimensional DSA (3D-DSA), and TOF-MRA. The reference test was a retrospective consensus between 2D-DSA images, 3D-DSA images, and source rotational DSA images. The evaluation included: detection of the residual flow, quantification of the flow, and validity of the decision regarding retreatment. Intraobserver agreement and interobserver agreement were determined. The sensitivity and specificity of residual flow detection ranged from 84.6 % (2D-DSA and TOF-MRA) to 92.3 % (3D-DSA) and from 91.3 % (TOF-MRA) to 97.8 % (3D-DSA), respectively. The accuracy of occlusion degree evaluation ranged from 0.78 (2D-DSA) to 0.92 (3D-DSA, Cohen's kappa). The 2D-DSA method presented lower performance in the decision on retreatment than 3D-DSA (P < 0.05, ROC analysis). The intraobserver agreement was very good for all techniques (κ = 0.80-0.97). The interobserver agreement was moderate for TOF-MRA and very good for 2D-DSA and 3D-DSA (κ = 0.72-0.94). Considering the invasiveness of DSA and the minor difference in the diagnostic performance between 3D-DSA and TOF-MRA, the latter method should be the first-line modality for follow-up after aneurysm embolization. (orig.)

  4. Follow-up after embolization of ruptured intracranial aneurysms: A prospective comparison of two-dimensional digital subtraction angiography, three-dimensional digital subtraction angiography, and time-of-flight magnetic resonance angiography

    Energy Technology Data Exchange (ETDEWEB)

    Serafin, Zbigniew; Strzesniewski, Piotr; Lasek, Wladyslaw [Nicolaus Copernicus University, Collegium Medicum, Department of Radiology and Diagnostic Imaging, Bydgoszcz (Poland); Beuth, Wojciech [Nicolaus Copernicus University, Collegium Medicum, Department of Neurosurgery and Neurotraumatology, Bydgoszcz (Poland)

    2012-11-15

    To prospectively compare of the diagnostic value of digital subtraction angiography (DSA) and time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. Seventy-two consecutive patients were examined 3 months after the embolization. The index tests included: two-dimensional DSA (2D-DSA), three-dimensional DSA (3D-DSA), and TOF-MRA. The reference test was a retrospective consensus between 2D-DSA images, 3D-DSA images, and source rotational DSA images. The evaluation included: detection of the residual flow, quantification of the flow, and validity of the decision regarding retreatment. Intraobserver agreement and interobserver agreement were determined. The sensitivity and specificity of residual flow detection ranged from 84.6 % (2D-DSA and TOF-MRA) to 92.3 % (3D-DSA) and from 91.3 % (TOF-MRA) to 97.8 % (3D-DSA), respectively. The accuracy of occlusion degree evaluation ranged from 0.78 (2D-DSA) to 0.92 (3D-DSA, Cohen's kappa). The 2D-DSA method presented lower performance in the decision on retreatment than 3D-DSA (P < 0.05, ROC analysis). The intraobserver agreement was very good for all techniques ({kappa} = 0.80-0.97). The interobserver agreement was moderate for TOF-MRA and very good for 2D-DSA and 3D-DSA ({kappa} = 0.72-0.94). Considering the invasiveness of DSA and the minor difference in the diagnostic performance between 3D-DSA and TOF-MRA, the latter method should be the first-line modality for follow-up after aneurysm embolization. (orig.)

  5. Digital subtraction angiography in traumatology

    International Nuclear Information System (INIS)

    Steudel, A.; Harder, T.; Lackner, K.; Schneider, B.; Orellano, L.; Bonn Univ.; Bonn Univ.

    1986-01-01

    The methods, indications and results of digital subtraction angiography in traumatology are presented, based on 56 examinations. The different use of intravenous or intraarterial DSA will be discussed with respect to expanding and localisation of traumatic vascular injury. DSA is recommended as the method of choice for follow-up after vascular reconstructive procedure. (orig.) [de

  6. Digital subtraction angiography

    International Nuclear Information System (INIS)

    Neuwirth, J. Jr.; Bohutova, J.

    1987-01-01

    The quality of radiodiagnostic methods to a great extent depends on the quality of the resulting image. The basic technical principles are summed up of the different parts of digital subtraction angiography apparatus and of methods of improving the image. The instrument is based on a videochain consisting of an X-ray tube, an intensifier of the radiographic image, optical parts, a video camera, an analog-to-digital converter and a computer. The main advantage of the digitally processed image is the possibility of optimizing the image into a form which will contain the biggest amount of diagnostically valuable information. Described are the mathematical operations for improving the digital image: spatial filtration, pixel shift, time filtration, image integration, time interval differentation and matched filtering. (M.D.). 8 refs., 3 figs

  7. Intraarterial digital subtraction angiography

    International Nuclear Information System (INIS)

    Davis, P.C.

    1987-01-01

    Digital subtraction angiography (DSA) refers to a radiographic technique of amplifying low levels of contrast from intravascular iodine into an acceptable image of vascular anatomy. Initial enthusiasm suggested that DSA using intravenous injections (IV-DSA) would eliminate most conventional film-screen angiographic studies. It was soon apparent, however, that IV-DSA examinations were often compromised in those patients who most needed a less invasive study. Indeed, only a 70 to 85 percent accuracy rate was achieved with IV-DSA, primarily due to motion artifact, poor cardiac output, overlap of pertinent vessels, and inability to resolve smaller vessels

  8. Digital subtraction angiography

    International Nuclear Information System (INIS)

    Gmelin, E.; Arlart, I.P.

    1987-01-01

    The introduction explains the technical and physical fundamentals of digital radiography, the principles of digital subtraction, and the various filtering methods. The authors then define the requirements to be met by a DSA equipment in terms of technical components and operational performance. A very extensive chapter deals with the indications supporting intravenous or intraarterial DSA and compares the two methods, showing advantages and drawbacks with respect to practical results. Another chapter discusses the applications of DSA for cardiological diagnostics, as e.g. imaging of the coronary arteries or arterial bypasses, and explains the densitometric and planimetric evaluation of the coronary functional processes. The book also discusses less customary applications of DSA such as the sialography or dacryocystography, as well as angiologic examinations in children. The limits of the DSA methods are discussed in the last chapter, together with aspects such as the radiation exposure of the patient, and cost-benefit analyses, and potential future improvements. With 204 figs., 44 tabs [de

  9. Digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Ludwig, J.W.; Eikelboom, B.C.; Van Schaik, C.C.; Taams, A.J.; Teeuwen, C.

    1985-01-01

    Besides the non-invasive techniques, angiography remains essential. The disadvantages of angiography are the complexity of the procedure and the possibility of complications. Digital subtraction angiography (DSA) is a considerable improvement in the examination of vessels. In DSA, subtraction combined with enhancement of the signals allows the use of intravenous injection to obtain good images of the arteries. However, when the contrast material is supplied intravenously, a rather large amount of contrast material is necessary to obtain images of good quality. Quantities of 30-40 cc of contrast material are required. The advantage of the intravenous injection of contrast material rather than the use of a catheter to deliver the contrast material in loco is that it is almost non-invasive thus circumventing the complications caused by catheter manipulation in the arterial system. This makes it possible to apply this method on an out-patient basis. DSA can also be applied with intra-arterial selective injection of the contrast material. In this case, the strong enhancement with DSA allows the use of a small quantity of contrast material while still obtaining images of the vessels with good contrast definition

  10. Exercise intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Yiannikas, J.

    1986-01-01

    Attempts to use exercise ventriculography have been made, not only to give diagnostic and perhaps even prognostic information in patients with coronary artery disease, but also in patients with valvular heart disease both before and after surgical intervention. Clearly an accurate method of assessing ventricular function under conditions of stress in various cardiac diseases would provide important information that would help in patient management. Exercise ventriculography using gated blood pool equilibrium technetium studies are widely used, but are limited by spatial resolution and by the foreshortening affects of visualizing the left ventricular chamber in the left anterior oblique view. First pass radionuclide studies have the added advantage of being able to visualize the ventricular chamber in the anterior or even the right anterior oblique view, but are even more limited by their spatial resolution problems. Several investigations have shown that digital subtraction angiography produces left ventricular images with a spatial resolution almost identical to that of conventional contrast ventriculography, but without the inherent problems of cardiac arrhythmias, which often limit the assessment of left ventricular function. Because of its ability to accurately delineate wall motion abnormalities, the technique may provide an adequate assessment of global and regional left ventricular function after exercise. Digital subtraction angiography may identify ischemic wall motion abnormalities produced by exercise in patients who already had significant permanent left ventricular damage from myocardial infarction

  11. Digital subtraction angiography of the heart and lungs

    International Nuclear Information System (INIS)

    Moodie, D.S.; Yiannikas, J.

    1986-01-01

    This book contains 12 chapters. Some of the chapter titles are: Physical Principles of Cardiac Digital Subtraction Angiography, The Use of Intravenous Digital Subtraction Angiography in Evaluating Patients with Complex Congenital Heart Disease, Exercise Intravenous Digital Subtraction Angiograpny, Cardiomyopathic and Cardiac Neoplastic Disease, Digital Subtraction Angiography in the Catheterization Laboratory, and Cardiac Digital Subtraction Angiography - Future Directions

  12. Development of digital subtraction system DAR-1200

    International Nuclear Information System (INIS)

    Kawai, Masumi; Shimizu, Yasumitsu; Ozaki, Takeshi; Sawada, Hiroshi; Uzuyama, Kazuhiro; Nishioka, Hiroyuki

    1989-01-01

    Digital subtraction angiography (DSA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. The merits of Shimadzu high resolution digital subtraction system DAR-1200 are reported in this paper. Furthermore, the principle and clinical usefullness of a new method of DSA called the Peak-Hold DSA are explained especially in details. (author)

  13. Digital subtraction angiography for breast cancer

    International Nuclear Information System (INIS)

    Tsurumi, Kiyohiko; Okuyama, Nobuo

    1987-01-01

    We performed digital subtraction angiography (DSA) on 42 patients with breast diseases to investigate its efficiency. As a result we came to the following conclusions: 1. The sensitivity was well evaluated in intraarterial digital subtraction angiography (IA-DSA) of breast. 2. IA-DSA could diagnose difficult cases like cancer which had undergone augmentation mammoplasty, or like Paget's disease and others. 3. DSA was a safe examination method. 4. The sensitivity of IA-DSA of breast cancer is superior to intravenous digital subtraction angiography (IV-DSA). (author)

  14. Subtracted versus non-subtracted digital imaging in peripheral angiography

    International Nuclear Information System (INIS)

    Fink, U.; Heywang, S.; Mayr, B.; Berger, H.

    1989-01-01

    Digital subtraction angiography (DSA) plays an important role in the management of vascular diseases of the lower extremities. A disadvantage is the lack of an automatically moving table top. We used a 1,024x1,024 matrix with a large-screen intensifier system and an automated 'stepping' facility. In 161 examinations of the arteries of the lower extremity digital peripheral arteriography was performed with and without the subtraction technique. We compared the influence of different iodine concentrations in DA and DSA. Peripheral DA proved to be equal to peripheral DSA in the region of the pelvis, thigh and knee, with no adequate contrasting being obtained merely in the region of the lower leg arteries in about 45%. It is necessary to use contrast medium at a concentration of 300 mg I/ml. The installation of an automated 'stepping' facility reduces the amount of contrast' medium needed and the exposure time. (orig.)

  15. Digital subtraction angiography in ischemic cerebrovascular accidents

    Energy Technology Data Exchange (ETDEWEB)

    Manelfe, C.; Bonafe, A.; Ducos de Lahitte, M.; Rascol, A.; Prere, J.; Guiraud, B.; Marc-Vergnes, J.P. (Hopital Purpan, 31 - Toulouse (France))

    1983-12-29

    Recent advances in computer and radiological technology have permitted reassessment of intravenous angiography in the evaluation of cerebrovascular disorders. Although digital subtraction angiography is a relatively new technique, it has rapidly gained a widespread acceptance. It has extended the use of angiography to outpatients and to people in whom conventional angiography is contraindicated. This reliable, safe, and relatively noninvasive technique offers the user two benefits: real-time subtraction and enhanced image quality. The system allows angiographic evaluation of the extracranial and intracranial vessels by means of intravenous injection of contrast material. Extracranial studies clearly demonstrate stenoses and occlusions of the major cervicocephalic arteries. Intracranial studies usually detect major cerebrovascular occlusions and provide insight into the collateral flow patterns. Intravenous digital subtraction angiography permits accurate assessment of cervicocephalic vessels after surgical repair. Although intravenous digital subtraction angiography obviates the need for conventional angiography in many cases, movements from the patients, or superimposition of vascular structures can substantially degrade the quality of the images. Digital subtraction angiography with intra-arterial injection of contrast medium will be contemplated in patients with poor intravenous digital subtraction angiography studies prior to surgery.

  16. Digital subtraction angiography in ischemic cerebrovascular accidents

    International Nuclear Information System (INIS)

    Manelfe, C.; Bonafe, A.; Ducos de Lahitte, M.; Rascol, A.; Prere, J.; Guiraud, B.; Marc-Vergnes, J.P.

    1983-01-01

    Recent advances in computer and radiological technology have permitted reassessment of intravenous angiography in the evaluation of cerebrovascular disorders. Although digital subtraction angiography is a relatively new technique, it has rapidly gained a widespread acceptance. It has extended the use of angiography to outpatients and to people in whom conventional angiography is contraindicated. This reliable, safe, and relatively noninvasive technique offers the user two benefits: real-time subtraction and enhanced image quality. The system allows angiographic evaluation of the extracranial and intracranial vessels by means of intravenous injection of contrast material. Extracranial studies clearly demonstrate stenoses and occlusions of the major cervicocephalic arteries. Intracranial studies usually detect major cerebrovascular occlusions and provide insight into the collateral flow patterns. Intravenous digital subtraction angiography permits accurate assessment of cervicocephalic vessels after surgical repair. Although intravenous digital subtraction angiography obviates the need for conventional angiography in many cases, movements from the patients, or superimposition of vascular structures can substantially degrade the quality of the images. Digital subtraction angiography with intra-arterial injection of contrast medium will be contemplated in patients with poor intravenous digital subtraction angiography studies prior to surgery [fr

  17. Digital subtraction angiography system evaluation with phantoms

    International Nuclear Information System (INIS)

    Wenstrup, R.S.; Sweeney, K.P.; Scholz, F.J.

    1985-01-01

    Advances in digital subtraction angiography imaging demonstrate the need for critical evaluation of the performance of digital subtraction equipment. The design of a phantom set for noninvasive assessment of the imaging quality of digital subtraction equipment is described; components include a remotely controlled transport system and individual patterns to evaluate the contrast and detail properties of the image intensifier, low-contrast sensitivity and resolution of the system, geometric distortion of image, linearity, mechanical and electronic stability of equipment, and effects of bone and bowel gas on iodine perception. The performance of an add-on digital radiographic system is presented, along with radiation exposure levels at the image intensifier for a range of radiographic techniques

  18. A simple digital subtraction angiographic instrument

    International Nuclear Information System (INIS)

    Ando, Hiroshi; Kobayashi, Tsuyoshi; Imai, Yutaka; Yanagishita, Akira

    1983-01-01

    A digital subtraction angiographic instrument was manufactured using a conventional x-ray TV for gastrointestinal series and a computer for processing of nuclear medical data. The results of visualization of the aorta and its primary branches were reviewed with demonstrable cases. (Chiba, N.)

  19. Digital subtraction angiography: myths and reality

    International Nuclear Information System (INIS)

    Levin, D.C.

    1984-01-01

    Some of the claims made about digital subtraction angiography (DSA) when it was first developed have turned out to be greatly exaggerated, and some members of the radiologic community have become disillusioned with its capabilities. The author discusses some of the limitations of DSA, and concludes that the advantages of DSA outweigh its limitations

  20. Digital subtraction angiography of carotid bifurcation

    International Nuclear Information System (INIS)

    Vries, A.R. de.

    1984-01-01

    This study demonstrates the reliability of digital subtraction angiography (DSA) by means of intra- and interobserver investigations as well as indicating the possibility of substituting catheterangiography by DSA in the diagnosis of carotid bifurcation. Whenever insufficient information is obtained from the combination of non-invasive investigation and DSA, a catheterangiogram will be necessary. (Auth.)

  1. Digital subtraction angiography: first 900 cases

    International Nuclear Information System (INIS)

    Rodgers, H.

    1984-01-01

    The diagnostic technique of digital subtraction angiography (DSA) is briefly outlined. The operational and technical experiences with a DR-960 DSA system used in the examination of the first 900 cases at St. Thomas' Hospital, London are described. (U.K.)

  2. Development of Shimadzu digital subtraction system

    International Nuclear Information System (INIS)

    Nishioka, Hiroyuki; Shibata, Koichi; Shimizu, Yasumitsu; Shibata, Kenji; Wani, Hidenobu

    1985-01-01

    Shimadzu has recently developed a digital subtraction system. It can perform intra-arterial digital subtraction angiography (DSA) using low concentration of contrast medium, or can visualize arteries with intravenuous injection. It can extremely reduce patient's pain in angiography. Image quality of DSA has been much improved by the development of high quality image amplifiers, improvement of signal-to-noise ratio of the x-ray television unit and the development of digital disk recorders. The peak-hold subtraction method that is now under clinical study presents images of blood vessels as the trace of the flow of contrast medium. The maximum-hold memory where the maximum value of the brightness in some period is stored for every picture element is subtracted from the minimum-hold memory where the minimum value is stored, and thus images of blood vessels can be obtained. Hardware of this method is rather simple and it is expected that the amount of contrast medium may be reduced or x-ray dose of the patient may be decreased. (author)

  3. Digital subtraction imaging in cardiac investigations

    International Nuclear Information System (INIS)

    Partridge, J.B.; Dickinson, D.F.

    1984-01-01

    The role of digital subtraction imaging (DSI) in the investigation of heart disease in patients of all ages, including neonates, was evaluated by the addition of a continuous fluoroscopy system to an existing, single-plane catheterisation laboratory. In some situations, DSI provided diagnostic images where conventional radiography could not and, in general, provided images of comparable quality to cineangiography. The total dose of contrast medium was usually less than that which would have been required for biplane cineangiography and the dose of radiation was always less. Digital subtraction imaging can make a significant contribution to the investigation of congenital heart disease and has some useful features in the study of acquired heart disease. (author)

  4. Tomosynthesis applied to digital subtraction angiography

    International Nuclear Information System (INIS)

    Kruger, R.A.; Sedaghati, M.; Roy, D.G.; Liu, P.; Nelson, J.A.; Kubal, W.; Del Rio, P.

    1984-01-01

    This extension of the author's previous work on tomographic digital subtraction angiography (DSA) describes the theory of tomosynthetic DSA image reconstruction techniques. In addition to developing the resolution limits resulting from x-ray exposure length and image intensifier field curvature, the authors describe one method of image formation and show tomosynthetic DSA images of animal and human anatomy. Methods for improving the present technique are discussed

  5. Physical principles of cardiac digital subtraction angiography

    International Nuclear Information System (INIS)

    Buonocore, E.; Pavlicek, W.

    1986-01-01

    Advances in the applications of computers with standard radiologic equipment have resulted in the development of electronic, or so-called ''film-less'' imaging. This technique, discussed by the authors, has become of particular value in the visualization of the central vascular system and has become known as digital subtraction angiography (DSA). Commercial products have become increasingly available and are capable of converting T.V. signals, obtained by conventional fluorography, to a computed array of digital values. Addition, subtraction, and averaging of this data, result in images with adequate signal-to-noise ratios that achieve detection of low concentrations of contrast media not possible with conventional screen film techniques. Computer subtraction of unnecessary background information improves the conspicuity of the opacified vessels to permit detection of vascular structures containing a concentration of no more than 1-3 percent of contrast media. This improved visualization is possible even with intravenous peripheral injections or reduced amounts of contrast media given intraarterially. With either method of contrast media administration, DSDA has become an excellent means of anatomic demonstration of the heart and great vessels with decreased morbidity and at lower cost

  6. Digital subtraction angiography of the thoracic aorta

    International Nuclear Information System (INIS)

    Grossman, L.B.; Buonocore, E.; Modic, M.T.; Meaney, T.F.

    1984-01-01

    Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram

  7. Digital subtraction angiography of the thoracic aorta

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, L.B.; Buonocore, E.; Modic, M.T.; Meaney, T.F.

    1984-02-01

    Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram.

  8. Clinical application of digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Morimoto, Tadashi; Kaku, Suiei; Morikawa, Eiji

    1984-01-01

    Intra-arterial digital subtraction angiography (IA-DSA) by the direct puncture of the carotid artery was described with special reference to its techniques, and cases were presented. This method was safe and painless and could be performed repeatedly. Cerebral angiographic images obtained by this method were either superior or fully compatible to the conventional cerebral angiography. It is therefore of great diagnostic value and can replace the conventional method. Furthermore, since the pretreatment is unnecessary and the time required is short, IA-DSA can be used as an adjuvant method for emergency diagnosis. (Namekawa, K)

  9. Application of digital subtraction angiography in disease of large cardiac vessel

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, Jun; Sone, Shusuke; Morimoto, Shizuo; Ikezoe, Junpei; Higashibara, Tokuro; Hanayama, Masayuki

    1983-06-01

    Digital subtraction angiography (DSA) was performed in 31 cases of disease of large cardiac vessel. DSA was useful for the diagnosis of aortic aneurysm and malformation of large vessels, follow-up after A-C bypass operation and Blalock's shunt operation for tetralogy of Fallot and as an adjuvant modality in cardiac catheterization.

  10. Application of digital subtraction angiography in disease of large cardiac vessel

    International Nuclear Information System (INIS)

    Arisawa, Jun; Sone, Shusuke; Morimoto, Shizuo; Ikezoe, Junpei; Higashibara, Tokuro; Hanayama, Masayuki

    1983-01-01

    Digital subtraction angiography (DSA) was performed in 31 cases of disease of large cardiac vessel. DSA was useful for the diagnosis of aortic aneurysm and malformation of large vessels, follow-up after A-C bypass operation and Blalock's shunt operation for tetralogy of Fallot and as an adjuvant modality in cardiac catheterization. (Chiba, N.)

  11. Multinuclide digital subtraction imaging in symptomatic prostnetic joints

    International Nuclear Information System (INIS)

    Chafetz, N.; Hattner, R.S.; Ruarke, W.C.; Helms, C.A.; Genant, H.K.; Murray, W.R.

    1985-01-01

    One hundred eleven patients with symptomatic prosthetic joints (86 hips, 23 knees, and two shoulders) were evaluated for prosthetic loosening and infection by combined technetium-99m-MDP/gallium-67 digital subtraction imaging. Clinical correlation was based on the assessment of loosening and bacterial cultures obtained at the time of surgery in 54 patients, joint aspiration cultures obtained in 37 patients, and long-term clinical follow-up for greater than 1.5 years in an additional 15 patients. Results revealed an 80-90% predictive value of a positive test for loosening, and a 95% predictive value of a negative test for infection. However, because of the low sensitivities and specificities observed, this approach to the evaluation of symptomatic prosthetic joints does not seem cost effective

  12. Digital subtraction angiography in patients with central vertigo

    International Nuclear Information System (INIS)

    Inamori, Toru; Takayasu, Yukio; Umetani, Yoshio; Taruoka, Akinori.

    1985-01-01

    Digital subtraction angiography (DSA) is a recently developed non-invasive intravenous angiography which has become possible through real time digital subtraction of x-ray transmission data from an image intensifier and television system. The output signals of the image intensifier-television camera system are digitized by an analog-digital converter. The digital information, 512x512 pixels and 9 bits deep, is fed into the image processing assembly after logarithmic amplification, where 2-8 frames are added and subtracted from mask images for the final digital images. Intravenous digital subtraction angiography was performed in 21 patients with intractable dizzy spells of central origin resistant to treatment. These patients showed some signs of CNS disturbance, although there were no significant findings on CT scans. Surprisingly, findings were abnormal in 14 of 21 patients (66.7%). DSA is, therefore, considered to be an important aid in the diagnosis of vertigo of the central type. (J.P.N.)

  13. Electronic Follow-Up of Developing World Cleft Patients: A Digital Dream?

    Science.gov (United States)

    Walker, Tom W M; Chadha, Ambika; Rodgers, William; Mills, Caroline; Ayliffe, Peter

    2017-10-01

    To identify potential access to telemedicine follow-up of children with clefts operated on a humanitarian mission. A cross-sectional study of parents of children presenting to a humanitarian cleft lip and palate mission in a Provincial Hospital in the Philippines. A purpose designed questionnaire was used to assess access to electronic and digital resources that could be used to aid follow-up. Forty-five (N = 45) parents of children having primary cleft lip and or palate surgery participated. There were no interventions. Access to the Internet was through Parent Perceived Affordability of Internet Access and Parent Owned Devices. Thirty-one (N = 31) respondents were female. There was 93% mobile phone ownership. The mean distance traveled to the clinic was 187 km. Majority (56%) were fluent in English. Thirty-one percent accessed the Internet daily. Sixteen percent reported use of e-mail. Fifty-one percent accessed the Internet on a mobile device, and short message service use was the most affordable means of communication. Due to perceived unaffordability and low levels of access to devices with cameras and the Internet, as well as issues with privacy, we cannot recommend relying on electronic follow-up of patients in the developing world.

  14. Myocardial perfusion imaging by digital subtraction angiography

    International Nuclear Information System (INIS)

    Kadowaki, Hiroyuki; Ishikawa, Kinji; Ogai, Toshihiro; Katori, Ryo

    1986-01-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; 1) at the R wave of the electrocardiogram, 2) 100 msec before the R wave, and 3) 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery. In all patients with anterior myocardial infarction, low perfusion was observed at the infarcted portion compared to the non-infarcted myocardium. In patients with inferior myocardial infarction, this low perfusion area was not observed because right coronary angiography was not subjected to DSA in this study. (J.P.N.)

  15. [Myocardial perfusion imaging by digital subtraction angiography].

    Science.gov (United States)

    Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

    1986-03-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Cardiac complications of intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Neergaard, K.; Dirksen, K.L.; Andersen, I.; Galloee, A.M.; Madsen, E.B.

    1989-01-01

    In a prospective study of 103 patients the incidence of cardiac events during intravenous digital subtraction angiography (i.v. DSA) was investigated. Of 103 patients 17 had known ischaemic heart disease. The examination was performed with an ionic contrast medium, Urografin 76% (sodium megluminediatrizoate), administered by bolus injection into the right atrium. Patients with severe cardiac disease were examined only if the procedure was considered of vital importance. Cardiac events were defined as ST-segment changes of more than 0.1 mV, changes in heart rate of more than 20%, arrhythmias and such symptoms as chest pain and dyspnoea. Ischaemic ST-segment changes during i.v. DSA were observed in approximately 20% of the patients and were not related to the presence of known ischaemic heart disease. Three patients developed angina during the procedure. Among 12 patients with known angina only one patient developed angina during the procedure. In this study chest pain was infrequent (3%), but there was a relative high frequency of ECG changes (20%) not related to patients with ischaemic heart disease only. It is concluded that there is a risk of cardiac events during i.v. DSA, but the risk is not increased in patients with known ischaemic heart disease (if they do not suffer from congestive heart failure) as compared with other patients without known ischaemic heart disease. (orig.)

  17. Digital subtraction cardiopulmonary angiography using FCR (Fuji computed radiography)

    International Nuclear Information System (INIS)

    Tanimura, Shigeo; Tomoyasu, Hiroshi; Banba, Jiro; Masaki, Mikio; Kanno, Yukio; Abe, Kazuo

    1987-01-01

    Digital subtraction cardiopulmonary angiography using FCR was performed on 46 patients including lung cancer, mediastinal tumor, giant bullous formation and others. The images of digital subtraction for pulmonary artery, pulmonary vein and thoracic aorta were studied by comparing to the conventional pulmonary angiogram. Good images of pulmonary artery due to digital subtraction were obtained in 80 % of the 45 cases. This method needed only half volume of contrast media compared to the conventional for obtaining good images and thus reduced side effect. Therefore this method seems to be an usefull pre-operative examination in various chest diseases, especially in case of lung cancer. (author)

  18. Temporal digital subtraction radiography with a personal computer digital workstation

    International Nuclear Information System (INIS)

    Kircos, L.; Holt, W.; Khademi, J.

    1990-01-01

    Technique have been developed and implemented on a personal computer (PC)-based digital workstation to accomplish temporal digital subtraction radiography (TDSR). TDSR is useful in recording radiologic change over time. Thus, this technique is useful not only for monitoring chronic disease processes but also for monitoring the temporal course of interventional therapies. A PC-based digital workstation was developed on a PC386 platform with add-in hardware and software. Image acquisition, storage, and processing was accomplished using 512 x 512 x 8- or 12-bit frame grabber. Software and hardware were developed to accomplish image orientation, registration, gray scale compensation, subtraction, and enhancement. Temporal radiographs of the jaws were made in a fixed and reproducible orientation between the x-ray source and image receptor enabling TDSR. Temporal changes secondary to chronic periodontal disease, osseointegration of endosseous implants, and wound healing were demonstrated. Use of TDSR for chest imaging was also demonstrated with identification of small, subtle focal masses that were not apparent with routine viewing. The large amount of radiologic information in images of the jaws and chest may obfuscate subtle changes that TDSR seems to identify. TDSR appears to be useful as a tool to record temporal and subtle changes in radiologic images

  19. The sloan digital sky Survey-II supernova survey: search algorithm and follow-up observations

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Bassett, Bruce [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701 (South Africa); Becker, Andrew; Hogan, Craig J. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Cinabro, David [Department of Physics, Wayne State University, Detroit, MI 48202 (United States); DeJongh, Fritz; Frieman, Joshua A.; Marriner, John; Miknaitis, Gajus [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Depoy, D. L.; Prieto, Jose Luis [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210-1173 (United States); Dilday, Ben; Kessler, Richard [Kavli Institute for Cosmological Physics, The University of Chicago, 5640 South Ellis Avenue Chicago, IL 60637 (United States); Doi, Mamoru [Institute of Astronomy, Graduate School of Science, University of Tokyo 2-21-1, Osawa, Mitaka, Tokyo 181-0015 (Japan); Garnavich, Peter M. [University of Notre Dame, 225 Nieuwland Science, Notre Dame, IN 46556-5670 (United States); Holtzman, Jon [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Jha, Saurabh [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, P.O. Box 20450, MS29, Stanford, CA 94309 (United States); Konishi, Kohki [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba, 277-8582 (Japan); Lampeitl, Hubert [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Nichol, Robert C. [Institute of Cosmology and Gravitation, Mercantile House, Hampshire Terrace, University of Portsmouth, Portsmouth PO1 2EG (United Kingdom); and others

    2008-01-01

    The Sloan Digital Sky Survey-II Supernova Survey has identified a large number of new transient sources in a 300 deg{sup 2} region along the celestial equator during its first two seasons of a three-season campaign. Multi-band (ugriz) light curves were measured for most of the sources, which include solar system objects, galactic variable stars, active galactic nuclei, supernovae (SNe), and other astronomical transients. The imaging survey is augmented by an extensive spectroscopic follow-up program to identify SNe, measure their redshifts, and study the physical conditions of the explosions and their environment through spectroscopic diagnostics. During the survey, light curves are rapidly evaluated to provide an initial photometric type of the SNe, and a selected sample of sources are targeted for spectroscopic observations. In the first two seasons, 476 sources were selected for spectroscopic observations, of which 403 were identified as SNe. For the type Ia SNe, the main driver for the survey, our photometric typing and targeting efficiency is 90%. Only 6% of the photometric SN Ia candidates were spectroscopically classified as non-SN Ia instead, and the remaining 4% resulted in low signal-to-noise, unclassified spectra. This paper describes the search algorithm and the software, and the real-time processing of the SDSS imaging data. We also present the details of the supernova candidate selection procedures and strategies for follow-up spectroscopic and imaging observations of the discovered sources.

  20. Digital Subtraction Angiography (DSA) "Road Map": An Angiographic Tool

    Science.gov (United States)

    Turski, P. A.; Stieghorst, M. F.; Strother, C. M.; Crummy, A. B.; Lieberman, R. P.; Mistretta, C. A.

    1982-12-01

    Continuous Digital subtraction combined with intraarterial injections of contrast medium permits the display of arterial structures during real time fluoroscopy. This DSA "road map" facilitates selective catheterization and has proved useful in interventional procedures.

  1. Fully digital data processing during cardiovascular implantable electronic device follow-up in a high-volume tertiary center.

    Science.gov (United States)

    Staudacher, Ingo; Nalpathamkalam, Asha Roy; Uhlmann, Lorenz; Illg, Claudius; Seehausen, Sebastian; Akhavanpoor, Mohammadreza; Buchauer, Anke; Geis, Nicolas; Lugenbiel, Patrick; Schweizer, Patrick A; Xynogalos, Panagiotis; Zylla, Maura M; Scholz, Eberhard; Zitron, Edgar; Katus, Hugo A; Thomas, Dierk

    2017-10-11

    Increasing numbers of patients with cardiovascular implantable electronic devices (CIEDs) and limited follow-up capacities highlight unmet challenges in clinical electrophysiology. Integrated software (MediConnect ® ) enabling fully digital processing of device interrogation data has been commercially developed to facilitate follow-up visits. We sought to assess feasibility of fully digital data processing (FDDP) during ambulatory device follow-up in a high-volume tertiary hospital to provide guidance for future users of FDDP software. A total of 391 patients (mean age, 70 years) presenting to the outpatient department for routine device follow-up were analyzed (pacemaker, 44%; implantable cardioverter defibrillator, 39%; cardiac resynchronization therapy device, 16%). Quality of data transfer and follow-up duration were compared between digital (n = 265) and manual processing of device data (n = 126). Digital data import was successful, complete and correct in 82% of cases when early software versions were used. When using the most recent software version the rate of successful digital data import increased to 100%. Software-based import of interrogation data was complete and without failure in 97% of cases. The mean duration of a follow-up visit did not differ between the two groups (digital 18.7 min vs. manual data transfer 18.2 min). FDDP software was successfully implemented into the ambulatory follow-up of patients with implanted pacemakers and defibrillators. Digital data import into electronic patient management software was feasible and supported the physician's workflow. The total duration of follow-up visits comprising technical device interrogation and clinical actions was not affected in the present tertiary center outpatient cohort.

  2. Digital subtraction angiography for breast diseases

    International Nuclear Information System (INIS)

    Okuyama, Nobuo; Okamoto, Yasushi; Kurita, Minoru; Nonaka, Naomichi; Ozawa, Yoshiyuki; Tsurumi, Kiyohiko

    1986-01-01

    We performed digital subtraction angiography (DSA) via arteries (IA-DSA) and veins (IV-DSA) on 42 patients with breast diseases to investigate its availability. The findings by DSA in cases with breast cancer included: tumor stains, hypervascularity and tortuosity, enlarged blood vessels, encasement and pooling. Metastatic lymph nodes and daughter nodules were also recognized by DSA. In benign tumors of the breast, a tumor stain was observed only in one case of fibroadenoma; otherwise no remarkable changes were noticed. The incidence of signs in cases with breast cancer using IA-DSA was 65 % for hypervascularity, 59 % for tumor stain, 41 % for vascular tortuosity and 41 % for enlargement of vessels. IV-DSA, on the contrary, revealed less incidences. However, tumor stain was seen frequently, and hypervascularity was seldom observed. The number of signs out of the abovementioned six appearing in each case was tabulated. With IA-DSA, there were 5 signs noted in 2 cases, but the majority had fewer: 4 cases in 4 cases and only 2 signs in 4 cases. There were no signs evident in 18 % of the cases. The incidence of the appearance of signs with IV-DSA was lower: there were no signs in 36 % of the cases. Therefore, the diagnostic accuracy of IA-DSA seemed to be fairly good in comparison with that of IV-DSA. The rate of appearance of abnormal signs was also examined, according to the size of the tumors. In IA-DSA, T 1 breast cancers revealed malignant signs in 80 % of the cases, in T 2 there were such signs 75 % and 100 % of the T 3 cases exhibited malignant signs, for an overall average of 82 %. In IV-DSA, T 1 showed 33 %, T 2 showed 70 %, and T 3 , 1 out of 1 case, showed malignant signs, 64 % altogether. It was the bigger the tumor, the larger the number of signs. The smallest breast cancer that exhibited abnormality in DSA was 1.0 x 0.7 cm in size. (J.P.N.)

  3. Digital contrast subtraction radiography for proximal caries diagnosis

    International Nuclear Information System (INIS)

    Kang, Byung Cheol; Yoon, Suk Ja

    2002-01-01

    To determine whether subtraction images utilizing contrast media can improve the diagnostic performance of proximal caries diagnosis compared to conventional periapical radiographic images. Thirty-six teeth with 57 proximal surfaces were radiographied using a size no.2 RVG-ui sensor (Trophy Radiology, Marne-la-Vallee, France). The teeth immersed in water-soluble contrast media and subtraction images were taken. Each tooth was then sectioned for histologic examination. The digital radiographic images and subtraction images were examined and interpreted by three dentists for proximal caries. The results of the proximal caries diagnosis were then verified with the results of the histologic examination. The proximal caries sensitivity using digital subtraction radiography was significantly higher than simply examining a single digital radiograph. The sensitivity of the proximal dentinal carious lesion when analyzed with the subtraction radiograph and the radiograph together was higher than with the subtraction radiograph or the radiograph alone. The use of subtraction radiography with contrast media may be useful for detecting proximal dentinal carious lesions.

  4. Digital subtraction arthrography of the hips and of the shoulders

    International Nuclear Information System (INIS)

    Fink, B.K.; Schedel, J.; Fink, U.; Hansen, M.; Hilbertz, T.; Hagena, F.W.

    1991-01-01

    In a study on 60 patients, it could be shown that very good results can be achieved in the region of the shoulder joint with the use of the digital subtraction technique and of digital image intensifier radiography. A further possibility of using the digital subtraction technique for proving endoprosthesis loosenings of the hip demonstrated its importance after a short time and has become a routine method in the meantime. These two examination techniques are displayed methodologically and their clinical possibilities of use are assessed in this contribution. (orig.)

  5. Digital subtraction angiography (DSA) of the heart and coronary arteries

    International Nuclear Information System (INIS)

    Struyven, J.J.; Delcour, C.; Brion, J.P.; Vandenbosch, G.; Claessens, J.

    1986-01-01

    Digital subtraction angiography has potential advantages over conventional radiography. The removal of background structures makes possible to visualize chambers of the heart, great vessels and coronary arteries with a lower iodine signal than with conventional cineangiography. Digital data used for imaging can been manipulated for assessment and quantitation of the ventricular fonction and the coronary circulation

  6. Digital subtraction radiography in the study of moving laryngeal structures

    International Nuclear Information System (INIS)

    Perri, G.; Falaschi, F.; Pieri, L.; Esposito, S.; Ursino, F.

    1988-01-01

    Digital subtraction radiography (DSR) was applied to the study of the larynx in 11 healthy subjects and 15 pathological cases. The method, consisting in the subtraction of images obtained at rest and during phonation or respiratory phases, allowed a clear definition of the normal moving structures - i.e. vocal cords, false cords, pyriform sinuses, thyroid cartilage. Moreover, several pathological conditions could be demonstrated. DSR asserts thus itself as a suitable technique in the functional evaluation of glottis

  7. Intraarterial digital subtraction angiography in neuroradiology

    International Nuclear Information System (INIS)

    Zeumer, H.

    1987-01-01

    Neuroradiology always could make best use of subtraction methods, due to the relative immobility and constant shape of the skull. Arterial DSA now has extended the potential uses while reducing the patient's radiation exposure, the contrast medium dosage and osmolarity. The considerable cut-back in time required for invasive examination has reduced the risk of diagnostic and therapeutic measures. The advantages consisting of immediate image display with high contrast resolution in most of the diagnostic tasks counterbalance the disadvantage of low focal resolution of the DSA in neuroradiology. Interventional neuroradiology today cannot do without i.a. DSA. (orig.) [de

  8. Intravenous digital subtraction angiography of transplanted kidney artery

    International Nuclear Information System (INIS)

    Tessier, J.P; Teyssou, H.; Verdier, J.P.; Tison, E.; Meyblum, J.; Marchal, M.

    1986-01-01

    Results of 351 intravenous digital subtraction angiographs (AN) of transplanted kidneys emphasized reliability of this examination for detection of renal artery stenosis. A prospective study of 219 patients (188 interpretable AN) showed significant stenosis of grafted artery in 22% of cases: 17% of the 126 patients with normal blood pressure and 34% of the 62 cases of hypertension. Digital subtraction allows, with a single injection, assessment of renal artery, nephrogram and excretory cavities, but it is not a substitute for conventional intravenous urography 1 to 2 months after grafting [fr

  9. Digital subtraction radiography in the study of the lacrimal system

    International Nuclear Information System (INIS)

    Falaschi, F.; Pieri, L.; Perri, G.; Signorini, G.; Genovese Ebert, F.

    1988-01-01

    The authors emphasize the usefulness of digital dacrycystography (DCG), as compared with various current technoques. Utilizing a radiographic unit equipped with a video-fluoroscopic system and interfaced to a digital video-processor, several digitalized images are acquired before, during and after the injection of contrast medium. Final images are obtained by subtraction of suitable pairs of source frames. Twenty-six patients affected by epiphora have been examined so far. In 21 cases digital subtraction DCG allowed an accurate visualization of the lacrimal system; in the other five patients the amount of information was acceptable. This methodology allows the assessment of both the normal anatomy of the lacrimal passages and their pathological patterns, such as obstructions, stenoses, fistulas, chronic dacrycystites, lacrimal stones. The examination is easy and quick to perform, with no discomfort for the patient. Digital subtraction DCG proves thus to be a very valuable technique thanks to its possible electronic elaboration - i.e. the subtraction and the magnification of images - to its better contrast resolution, and to the possibility it yields of dynamic studies under radioscopic control

  10. Motion subtraction of the larynx using digital radiography

    International Nuclear Information System (INIS)

    Kumakawa, Kohzoh; Miyakawa, Kouichi

    1990-01-01

    The development of digital radiography (DR) has made it possible to analyze the contour of the laryngeal soft tissue structures in more detail than the conventional screen-film method. The authors first used the DR system for time subtraction of the larynx during inspiration and phonation. The images are acquired by means of frontal tomography of the larynx using the imaging plate during inspiration and phonation separately, and stored into the memory of the DR system. The thickness of the slices is 5.0 mm. Time subtraction between the mask image during inspiration and the live image during phonation is performed using digital processing on CRT. Superimposing the two images at the upper trachea and the thyroid cartilage of the same depth, makes it possible to measure movement of the vocal cord and false vocal cord quantitatively in three dimensions. The authors named this time subtraction as motion subtraction of the larynx. This motion subtraction image can be obtained by on-line digital processing without complicated development technique, but has so high spatial resolution. This image processing seems to be useful in functional radiographic analysis of laryngeal diseases. (author)

  11. Use of digital subtraction angiography for renal transplant evaluation

    International Nuclear Information System (INIS)

    Fanucci, E.; Orlacchio, A.; Pocek, M.; Svegliati, F.

    1986-01-01

    Intravenous digital subtraction angiography (IVDSA) was used to evaluate 6 renal allograft recipients and 3 potential renal donors. In 4 potential renal donors and in 2 allograft recipients, angiographic data were confirmed by surgery. IVDSA is a safe, accurate, easily performed, outpatient procedure; in our opinion DSA should became the procedure of choice to study vascular anatomy in renal transplant evaluation

  12. Digital subtraction angiography in the diagnosis of Fallot's tetralogy

    International Nuclear Information System (INIS)

    Ivanitskij, A.V.; Tereshkin, Ya.A.; Sobolev, A.V.; Stolyar, V.L.; Slyunyastikov, M.A.

    1995-01-01

    The authors analyze the efficacy of digital subtraction angiography (DSA) in the diagnosis of Fallot's tetralogy (FT); this method helps simplity and cut down their scope of investigations but does not deteriorate their informative value. DSA findings in 120 patients with TF are analyzed. 5 refs.; 6 figs

  13. New electronic filtering technique in digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Stacul, F; Pozzi-Mucelli, R; Predonzan, F; Magnaldi, S; Godina, G

    1986-01-01

    The authors report their experience with a new electronic filtering technique in digital subtraction angiography (DSA). The principles of the technique are reported and the advantages in comparison with conventional filters are stressed (accurate and fast placement without fluoroscopic exposure). The system provided excellent results in about 900 DSA examinations.

  14. Pulmonary ventilation in children digital subtraction study

    International Nuclear Information System (INIS)

    Schmit, P.; Faure, C.; Sardet, A.; Bacques, O.

    1985-01-01

    Digital technique such as used in digital angiography can be used to study areas which lucency varies with time. A TID technique (time interval difference) has been used to study the lucency variation of the lung in children. This method has been used in 130 children with a mean age of 2 years and 8 months. In 85 children, the TID was normal: 5 false negative studies were found in this group. In the other 47 cases, the anomaly of the TID was due to a perfusion or a ventilation anomaly or both. No false positive are found. In 13 patients, comparison between the TID findings and the perfusion and ventilation nuclear scan was possible. In 9 patients, the correlation was excellent, the TID giving more some informations about the pulmonary mixic [fr

  15. ECG-gating in non-cardiac digital subtraction angiography

    International Nuclear Information System (INIS)

    Gattoni, F.; Baldini, V.; Cairo, F.

    1987-01-01

    This paper reports the results of the ECG-gating in non-cardiac digital subtraction angiography (DSA). One hundred and fifteen patients underwent DSA (126 examinations); ECG-gating was applied in 66/126 examinations: images recorded at 70% of R wave were subtracted. Artifacts produced by vascular movements were evaluated in all patients: only 40 examinations, carried out whithout ECG-gating, showed vascular artifacts. The major advantage of the ECG-gated DSA is the more efficent subtraction because of the better images superimposition: therefore, ECG-gating can be clinically helpful. On the contrary, it could be a problem in arrhytmic or bradycardic patients. ECG-gating is helpful in DSA imaging of the thoracic and abdominal aorta and of the cervical and renal arteries. In the examinations of peripheral vessels of the limbs it is not so efficent as in the trunk or in the neck

  16. A study of transverse image reconstruction with digital subtraction angiography

    International Nuclear Information System (INIS)

    Sakamoto, Kiyoshi; Kotoura, Noriko; Terasawa, Yuuji; Oda, Masahiko; Gotou, Hiroshi; Nasada, Toshiya; Tanooka, Masao

    1995-01-01

    For digital subtraction angiography (DSA) with C-type equipment, it is possible to radiate an X-ray during rotation and to collect data at different angular settings. We tried to reconstruct transverse image from data obtained by scanning DSA images at different angular settings. 88 projection data were obtained by rotating the object at 180deg during radiation. Reconstruction was made using the convolution method with pixel value distribution for each projection. Similarly, the image quality of the reconstructed images were compared with the unsubtracted and subtracted ones. In case a part object was outside the calculating region, artifacts were generally produced. However, the artifacts were reduced by subtracting the background from the image. In addition, the cupping phenomenon caused by beam hardening was relaxed and high-quality imaging could be achieved. This method will become even more effective, if we will use it with selective angiography in which the limited area is enhanced. (author)

  17. Method and apparatus for performing digital intravenous subtraction angiography

    International Nuclear Information System (INIS)

    Stein, J.A.

    1986-01-01

    This invention relates to digital intravenous subtraction angiography (DISA), and more particularly concerns novel apparatus and techniques for providing high resolution angiograms with equipment that coacts with existing standard medical X-ray equipment. A typical medical X-ray generator provides low mA, continuous X-ray exposures illuminating a standard image intensifier producing an image scanned by a conventional television camera to produce a video signal. An analog-to-digital converter digitizes the signal, and adding means adds the digital frame signals together in real time to provide an intermediate digital signal representing the addition of 5 to 20 frames. Digital storage means store the intermediate image signals. Preferably there are two system memories with means for summing a subsequent intermediate image in the second memory while a previously-formed intermediate image is being transferred to disk storage

  18. Evaluation of the pulmonary vascular bed by digital subtraction angiography

    International Nuclear Information System (INIS)

    Shikuwa, Masahiro; Asai, Sadahiro; Hara, Shiro; Yamasa, Toshihiko; Miyahara, Yoshiyuki; Hara, Kohei; Nishijima, Kyoji.

    1995-01-01

    We studied the usefulness of digital subtraction angiography for evaluating the pulmonary capillary bed. Four individuals underwent the procedure. One was a healthy volunteer and the others were patients with chronic pulmonary emphysema. During catheterization, an 8 F balloon catheter was manipulated into the right pulmonary artery. A total of 20 ml of contrast material was injected at a rate of 10 ml/sec at full inspiration. In the normal subject, the capillary bed filled homogeneously and no defect was seen. In the patients, the pulmonary artery was nearly normal, but severe defects were observed in the pulmonary capillaries. Contrast resolvability was greater with digital subtraction pulmonary angiography than with pulmonary perfusion scintigraphy or pulmonary arteriography. This technique makes possible the visual evaluation of the pulmonary capillary bed. (author)

  19. Digital subtraction angiography in the assessment of cardiovascular disease

    International Nuclear Information System (INIS)

    Harrington, D.P.; Boxt, L.M.

    1985-01-01

    Digital subtraction angiography (DSA) is a new radiographic method for evaluating the cardiovascular system. It represents another in a continuing series of computer-assisted diagnostic imaging modalities. The advantages of this technique are its relatively noninvasive nature combined with diagnostically acceptable angiographic images of a variety of cardiovascular structures. Major clinical applications of DSA include its use in imaging of localized regions of peripheral arterial disease and as a screening procedure in evaluating extracranial carotid and vertebral artery disease and renovascular hypertension. Cardiac applications of DSA include assessment of ventricular function, recognition and quantification of intracardiac shunts, visualization of coronary artery bypass grafts, and the study of complex congenital cardiac malformations. Digital subtraction angiography may also be used to evaluate intracranial aneurysms and vascular tumors

  20. Practical applications and methods in performing cardiac digital subtraction angiography

    International Nuclear Information System (INIS)

    Markovic, D.M.; Withrow, S.; Moodie, D.S.

    1986-01-01

    One of the purposes of this book is to outline the utility of digital subtraction angiography (DSA) in common clinical practice. No text has dealt with the actual physical setup of the room or the patient prior and during a digital subtraction angiographic study at rest and with exercise. This chapter outlines the steps commonly used when cardiac DSA is performed on patients in the authors' laboratory. The authors have learned over the last few years the best way to prepare the patient and the equipment and it is hoped that utilizing this experience, other centers may avoid the mistakes the authors have made in the past and develop new techniques for the future

  1. Digital subtraction angiography in pediatric cerebrovascular occlusive disease

    International Nuclear Information System (INIS)

    Faerber, E.N.; Griska, L.A.B.; Swartz, J.D.; Capitanio, M.A.; Popky, G.L.

    1984-01-01

    While conventional angiography has been used to demonstrate cerebrovascular occlusive disease in the past, digital subtraction angiography (DSA) is capable of showing progressive vascular involvement with ease, simplicity, and extremely low morbidity, making it particularly well suited for children and outpatients either alone or coordinated with computed tomography. The authors discuss the usefulness and advantages of DSA as demonstrated in 7 infants and children with hemiplegia, 4 of whom had sickle-cell disease

  2. Intravenous digital subtraction angiography investigation of reversible cerebral ischemia

    International Nuclear Information System (INIS)

    Pistolesi, G.F.; Maso, R.; Filosto, L.; Piovan, E.; Morgante, D.; Taddei, G.; Tonegutti, M.; Portuese, A.

    1986-01-01

    The brachio-cephalic, carotid, vertebral and intra-cranial vessels of 497 patients presenting reversible ischemic attacks (R.I.A) were evaluated with venous digital subtraction angiography (V.D.S.A.). Alterations of the vascular wall were observed in 289/497 (58.2%) patients, of whom 60% presented multiple locations (539 lesions): obstruction (12%), stenosis >50% (29%), stenosis 50%. The incidence of vascular lesions was higher (p [fr

  3. Is digital substraction angiography still needed for the follow-up of intracranial aneurysms treated by embolisation with detachable coils?

    International Nuclear Information System (INIS)

    Lubicz, Boris; Neugroschl, Carine; Collignon, Laurent; Francois, Olivier; Baleriaux, Danielle

    2008-01-01

    Follow-up of intracranial aneurysms treated by embolisation with detachable coils is mandatory to detect a possible recanalisation. The aim of this study was to compare contrast-enhanced magnetic resonance angiography (CE-MRA) with digital substraction angiography (DSA) used to detect aneurysm recanalisation to determine if DSA is still needed during follow-up. From May 2006 to May 2007, 55 patients with 67 aneurysms were treated by endosaccular coiling with (n=9) or without (n=58) an adjunctive stent. Follow-up imaging protocol included MRA at 6 and 12 months and a DSA at 12 months or earlier if a major recanalisation was identified on the 6-month MRA. Two neuroradiologists independently reviewed MRA images (readers 1 and 2) and two other reviewed DSA images. Follow-up DSA showed stability of the aneurysm occlusion in 52 cases, recanalisation in 14 cases, and further thrombosis in one. On CE-MRA, both readers identified all recanalisations but one (sensitivity of 93%) as they missed a major recanalisation in a 2-mm ruptured aneurysm. There were two false-positive evaluations by reader 1 and three for reader 2. Mean specificity of CE-MRA to detect aneurysm recanalisation was 95.5%. CE-MRA is accurate to detect aneurysm recanalisation after embolisation with detachable coils. CE-MRA may be proposed as first-intention imaging technique for their follow-up. However, its sensitivity and specificity remain inferior to that of DSA and major recurrences may be missed in very small aneurysms. Therefore, a single DSA remains mandatory during the imaging follow-up. (orig.)

  4. Digital subtraction cerebral angiography by intraarterial injection: comparison with conventional angiography

    International Nuclear Information System (INIS)

    Brant-Zawadzki, M.; Gould, R.; Norman, D.; Newton, T.H.; Lane, B.

    1983-01-01

    For 4 months, a prototype digital subtraction system was used to obtain images of the cerebral vasculature after intraarterial contrast injections. In 12 instances, the intraarterial injections were recorded with both a digital subtraction unit and conventional direct magnification film-screen system. The digital subtraction and conventional film subtraction images were compared and graded for quality and information content by three skilled observers. In addition, quantitative measurements of contrast-detail performance and spatial resolution were obtained on both the digital system and the screen-film imaging chain. In a clinical setting, both the digital subtraction and conventional film-screen systems provided similar quality images and angiographic information. Contrast-detail curves demonstrated that digital subtraction angiography outperformed conventional film technique for low-contrast objects. Digital subtraction angiography also reduced the time required to obtain the angiogram, markedly reduced film cost, and lowered the contrast agent burden

  5. Hybrid intravenous digital subtraction angiography of the carotid bifurcation

    International Nuclear Information System (INIS)

    Burbank, F.H.; Enzmann, D.; Keyes, G.S.; Brody, W.R.

    1984-01-01

    A hybrid digital subtraction angiography technique and noise-reduction algorithm were used to evaluate the carotid bifurcation. Temporal, hybrid, and reduced-noise hybrid images were obtained in right and left anterior oblique projections, and both single- and multiple-frame images were created with each method. The resulting images were graded on a scale of 1 to 5 by three experienced neuroradiologists. Temporal images were preferred over hybrid images. The percentage of nondiagnostic examinations, as agreed upon by two readers, was higher for temporal alone than temporal + hybrid. In addition, also by agreement between two readers, temporal + hybrid images significantly increased the number of bifurcations seen in two views (87%) compared to temporal subtraction alone

  6. Introduction to the principles of Digital Subtraction Angiography (DSA)

    International Nuclear Information System (INIS)

    Kaplanis, P.

    1997-01-01

    Medical applications of advanced technology have rapidly become more sophisticated and more widespread. The field of diagnostic imaging is by no means an exception. There has been a number of breathtaking developments in the field of medical imaging in recent years. Today higher quality, greater clarity and more minute precision are considered not advantages but necessities. Hence new developments are concentrated in the data acquisition and image processing based on the microprocessor controlled modules interfaced with state of the art radiological imaging equipment. One such development is the subtraction of x-rays vis a computer for better visualization of blood vessels, cavities of the heart and of the coronary and pulmonary vascular system. This procedure is termed Digital Subtraction Angiography (DSA). (author)

  7. Introduction to the principles of Digital Subtraction Angiography (DSA)

    Energy Technology Data Exchange (ETDEWEB)

    Kaplanis, P [Medical Physics Department, Nicosia General Hospital, Nicosia (Cyprus)

    1998-12-31

    Medical applications of advanced technology have rapidly become more sophisticated and more widespread. The field of diagnostic imaging is by no means an exception. There has been a number of breathtaking developments in the field of medical imaging in recent years. Today higher quality, greater clarity and more minute precision are considered not advantages but necessities. Hence new developments are concentrated in the data acquisition and image processing based on the microprocessor controlled modules interfaced with state of the art radiological imaging equipment. One such development is the subtraction of x-rays vis a computer for better visualization of blood vessels, cavities of the heart and of the coronary and pulmonary vascular system. This procedure is termed Digital Subtraction Angiography (DSA). (author). 5 refs, 3 figs.

  8. Evaluation and quality control of digital subtraction angiography systems

    International Nuclear Information System (INIS)

    Louisot, P.

    1986-04-01

    After reviewing the development of systems used in angiography, we rewind the medical interest and describe the steps of an angiographic examination. The following chapter is dedicated to the techniques used for the digitalization of video images. The components of the system involved in the image acquisition are thoroughly investigated in chapter 4. Then, we analyse the capabilities of the machines available in France in 1985. Chapter 6 is devoted to the criteria of quality in digital imaging. In order to assign qualitative values to the above criteria, we design a control procedure which is described in chapter 7. The procedure thus allows the estimate of the physical performances of angiographic digital subtraction systems [fr

  9. Evaluation of left ventricular function using digital subtraction ventriculography

    International Nuclear Information System (INIS)

    Yiannikas, J.; Detrano, R.

    1986-01-01

    Digital subtraction ventriculography following injections of contrast via peripheral veins provides excellent images to assess left ventricular function. The images are essentially identical to those following DCV, but allow more uniform mixing of contrast in the left ventricular chamber. Furthermore, few, if any, cardiac arrhythmias occur, hence obviating difficulties that arise from DCV. The spatial resolution of the method is such that regional wall motion assessment of ventricular function is more accurate than that of other noninvasive imaging methods. The use of video-densitometry allows accurate assessment of left ventricular function even when the left ventricular cavity is nonsymmetrically deformed and aneurysmal. In the setting of the cardiac catheterization laboratory, digital ventriculography may provide a safer means of assessing left ventricular function when critical coronary or myocardial disease is present and allows multiple assessments of ventricular function during the same study. Although excellent correlations with standard ventriculography have been noted by all workers, significant discrepancies still exist in individual patients, particularly in the calculations of end diastolic volumes. In the authors experience and in those of most workers, the largest discrepancies existed in patients in whom suboptimal studies are included for analysis. The most frequent reason for the occasional suboptimal study as with all digital subtraction work is the misregistration that results from motion

  10. Digital subtraction angiography in the evaluation of chemodectomas

    International Nuclear Information System (INIS)

    Vlahos, L.; Papathanasiou, M.; Gouliamos, A.; Dimakakos, P.; Papavassiliou, C.

    1988-01-01

    During the last 2 years eleven patients with surgically confirmed chemodectomas have been investigated by means of digital subtraction angiography (DSA). Seven patients underwent i.v. DSA, which revealed eight carotid body tumours, and in the remaining four with jugulotympanic chemodectomas intra-arterial (i.a.) DSA was performed. We found i.v. DSA an easy and satisfactory method for the investigation of carotid body tumours but when glomus intravagale, tympanicum or jugulare is suspected an i.a. selective injection is required. (orig.) [de

  11. Digital subtraction angiography in the evaluation of chemodectomas

    Energy Technology Data Exchange (ETDEWEB)

    Vlahos, L.; Papathanasiou, M.; Gouliamos, A.; Dimakakos, P.; Papavassiliou, C.

    1988-05-01

    During the last 2 years eleven patients with surgically confirmed chemodectomas have been investigated by means of digital subtraction angiography (DSA). Seven patients underwent i.v. DSA, which revealed eight carotid body tumours, and in the remaining four with jugulotympanic chemodectomas intra-arterial (i.a.) DSA was performed. We found i.v. DSA an easy and satisfactory method for the investigation of carotid body tumours but when glomus intravagale, tympanicum or jugulare is suspected an i.a. selective injection is required.

  12. Real-time digital x-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

    1982-01-01

    A method of producing visible difference images derived from an x-ray image of an anatomical subject is described. X-rays are directed through the subject, and the image is converted into television fields comprising trains of analog video signals. The analog signals are converted into digital signals, which are then integrated over a predetermined time corresponding to several television fields. Difference video signals are produced by performing a subtraction between the ongoing video signals and the corresponding integrated signals, and are converted into visible television difference images representing changes in the x-ray image

  13. Clinical application of digital subtraction angiography for arterial portography

    International Nuclear Information System (INIS)

    Ohtomo, Kuni; Furui, Shigeru; Yashiro, Naofumi; Itai, Yuji; Iio, Masahiro

    1983-01-01

    Intra-arterial digital subtraction portography(IADSP) after superior mesenteric artery injection was described. A total dose of 15 ml to 20 ml of 76% contrast medium was injected at a rate of 5 ml/sec in 14 cases (9 hepatomas, 2 metastatic liver tumors, 2 cavernous hemangiomas, 1 liver cirrhosis). In 11 cases, portal venous system was clearly demonstrated by IADSP. In 8 hepatomas tumor thrombus of portal venous system could be ruled out by IADSP and embolization therapy was carried out. IADSP was also useful for demonstrating esophageal varix and splenorenal shunt. (author)

  14. Intra-arterial digital subtraction angiography of the carotid arteries

    International Nuclear Information System (INIS)

    Nakstad, P.; Bakke, S.J.; Kjartansson, O.; Nyhus, S.

    1986-01-01

    A cross-over test in intra-arterial digital subtraction angiography (IADSA) of the carotid arteries was performed in 50 patients to evaluate image quality and side-effects with iohexol and metrizoate injected at concentrations of 100 mg I/ml by hand. The image quality was excellent or good in all cases. Although the severity and the frequency of side-effects were higher with metrizoate, both contrast media were suitable for IADSA at this low concentration. No complications were seen. It was assumed that the risk with IADSA was less than that of conventional-selectivity and with small amounts of contrast media, as in this study. (orig.)

  15. [Design and development of the DSA digital subtraction workstation].

    Science.gov (United States)

    Peng, Wen-Xian; Peng, Tian-Zhou; Xia, Shun-Ren; Jin, Guang-Bo

    2008-05-01

    According to the patient examination criterion and the demands of all related departments, the DSA digital subtraction workstation has been successfully designed and is introduced in this paper by analyzing the characteristic of video source of DSA which was manufactured by GE Company and has no DICOM standard interface. The workstation includes images-capturing gateway and post-processing software. With the developed workstation, all images from this early DSA equipment are transformed into DICOM format and then are shared in different machines.

  16. Digital subtraction angiography in head and neck radiology

    International Nuclear Information System (INIS)

    Carmody, R.F.; Seeger, J.F.; Smith, R.L.; Horsley, W.W.; Miller, R.W.

    1984-01-01

    Intravenous digital subtraction angiography (IVDSA) was used to evaluate 44 patients with suspected otolaryngologic abnormalities. Sixteen had IVDSA for pulsatile tinnitus or suspected glomus tumor of the petrous bone. Nine patients were evaluated because of pulsatile neck masses, and 12 others had suspected tumors of the neck, face, and paranasal sinuses. Seven had IVDSA following head and neck trauma. The technique of examination is described. The current indications of IVDSA in head and neck radiology are discussed. It is concluded that IVDSA is a suitable substitute for conventional angiography for many otolaryngologic conditions and, because of its safety, can be used more liberally. (orig.)

  17. Digital subtraction angiography in head and neck radiology

    Energy Technology Data Exchange (ETDEWEB)

    Carmody, R F; Seeger, J F; Smith, R L; Horsley, W W; Miller, R W

    1984-07-01

    Intravenous digital subtraction angiography (IVDSA) was used to evaluate 44 patients with suspected otolaryngologic abnormalities. Sixteen had IVDSA for pulsatile tinnitus or suspected glomus tumor of the petrous bone. Nine patients were evaluated because of pulsatile neck masses, and 12 others had suspected tumors of the neck, face, and paranasal sinuses. Seven had IVDSA following head and neck trauma. The technique of examination is described. The current indications of IVDSA in head and neck radiology are discussed. It is concluded that IVDSA is a suitable substitute for conventional angiography for many otolaryngologic conditions and, because of its safety, can be used more liberally.

  18. IMPROVED BACKGROUND SUBTRACTION FOR THE SLOAN DIGITAL SKY SURVEY IMAGES

    International Nuclear Information System (INIS)

    Blanton, Michael R.; Kazin, Eyal; Muna, Demitri; Weaver, Benjamin A.; Price-Whelan, Adrian

    2011-01-01

    We describe a procedure for background subtracting Sloan Digital Sky Survey (SDSS) imaging that improves the resulting detection and photometry of large galaxies on the sky. Within each SDSS drift scan run, we mask out detected sources and then fit a smooth function to the variation of the sky background. This procedure has been applied to all SDSS-III Data Release 8 images, and the results are available as part of that data set. We have tested the effect of our background subtraction on the photometry of large galaxies by inserting fake galaxies into the raw pixels, reanalyzing the data, and measuring them after background subtraction. Our technique results in no size-dependent bias in galaxy fluxes up to half-light radii r 50 ∼ 100 arcsec; in contrast, for galaxies of that size the standard SDSS photometric catalog underestimates fluxes by about 1.5 mag. Our results represent a substantial improvement over the standard SDSS catalog results and should form the basis of any analysis of nearby galaxies using the SDSS imaging data.

  19. Role of digital tomosynthesis and dual energy subtraction digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Sharma, Madhurima; Sandhu, Manavjit Singh; Gorsi, Ujjwal; Gupta, Dheeraj; Khandelwal, Niranjan

    2015-01-01

    Highlights: • Digital tomosynthesis and dual energy subtraction digital radiography are modifications of digital radiography. • These modalities perform better than digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis. • Digital tomosynthesis has a sensitivity of 100% in detection of cavities. • Centrilobular nodules seen on CT in active pulmonary tuberculosis, were also demonstrated on digital tomosynthesis in our study. • Digital tomosynthesis can be used for diagnosis and follow up of patients in pulmonary tuberculosis, thereby reducing the number of CT examinations. - Abstract: Objective: To assess the role of digital tomosynthesis (DTS) and dual energy subtraction digital radiography (DES-DR) in detection of parenchymal lesions in active pulmonary tuberculosis (TB) and to compare them with digital radiography (DR). Materials and methods: This prospective study was approved by our institutional review committee. DTS and DES-DR were performed in 62 patients with active pulmonary TB within one week of multidetector computed tomography (MDCT) study. Findings of active pulmonary TB, that is consolidation, cavitation and nodules were noted on digital radiography (DR), DTS and DES-DR in all patients. Sensitivity, specificity, positive and negative predictive values of all 3 modalities was calculated with MDCT as reference standard. In addition presence of centrilobular nodules was also noted on DTS. Results: Our study comprised of 62 patients (33 males, 29 females with age range 18–82 years). Sensitivity and specificity of DTS for detection of nodules and cavitation was better than DR and DES-DR. Sensitivity and specificity of DTS for detection of consolidation was comparable to DR and DES-DR. DES-DR performed better than DR in detection of nodules and cavitation. DTS was also able to detect centrilobular nodules with sensitivity and specificity of 57.4% and 86.5% respectively. Conclusion: DTS and DES-DR perform better

  20. Role of digital tomosynthesis and dual energy subtraction digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Madhurima, E-mail: madhurimashrm88@gmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Sandhu, Manavjit Singh, E-mail: manavjitsandhu@yahoo.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Gorsi, Ujjwal, E-mail: ujjwalgorsi@gmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Gupta, Dheeraj, E-mail: dheeraj1910@gmail.com [Department of Pulmonary Medicine, PGIMER, Chandigarh 160012 (India); Khandelwal, Niranjan, E-mail: khandelwaln@hotmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India)

    2015-09-15

    Highlights: • Digital tomosynthesis and dual energy subtraction digital radiography are modifications of digital radiography. • These modalities perform better than digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis. • Digital tomosynthesis has a sensitivity of 100% in detection of cavities. • Centrilobular nodules seen on CT in active pulmonary tuberculosis, were also demonstrated on digital tomosynthesis in our study. • Digital tomosynthesis can be used for diagnosis and follow up of patients in pulmonary tuberculosis, thereby reducing the number of CT examinations. - Abstract: Objective: To assess the role of digital tomosynthesis (DTS) and dual energy subtraction digital radiography (DES-DR) in detection of parenchymal lesions in active pulmonary tuberculosis (TB) and to compare them with digital radiography (DR). Materials and methods: This prospective study was approved by our institutional review committee. DTS and DES-DR were performed in 62 patients with active pulmonary TB within one week of multidetector computed tomography (MDCT) study. Findings of active pulmonary TB, that is consolidation, cavitation and nodules were noted on digital radiography (DR), DTS and DES-DR in all patients. Sensitivity, specificity, positive and negative predictive values of all 3 modalities was calculated with MDCT as reference standard. In addition presence of centrilobular nodules was also noted on DTS. Results: Our study comprised of 62 patients (33 males, 29 females with age range 18–82 years). Sensitivity and specificity of DTS for detection of nodules and cavitation was better than DR and DES-DR. Sensitivity and specificity of DTS for detection of consolidation was comparable to DR and DES-DR. DES-DR performed better than DR in detection of nodules and cavitation. DTS was also able to detect centrilobular nodules with sensitivity and specificity of 57.4% and 86.5% respectively. Conclusion: DTS and DES-DR perform better

  1. Digital subtraction angiography with an Isocon camera system: clinical applications

    International Nuclear Information System (INIS)

    Barbaric, Z.L.; Gomes, A.S.; Deckard, M.E.; Nelson, R.S.; Moler, C.L.

    1984-01-01

    A new imaging system for digital subtraction angiography (DSA) was evaluated in 30 clinical studies. The image receptor is a 25 X 25 cm, 12 par gadolinium oxysulfate rare-earth screen whose light output is focused to a low-light-level Isocon camera. The video signal is digitized and processed by an image-array processor containing 31 512 X 512 memories 8 bits deep. In most patients, intraarterial DSA studies were done in conjunction with conventional arteriography. In these arterial studies, images adequate to make a specific diagnosis were obtained using half the radiation dose and half the amount of contrast material needed for conventional angiography. In eight intravenous studies performed either to identify renal artery stenosis or for evaluation of congenital heart anomalies, the images were diagnostic but objectionably noisy

  2. Real-time digital X-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

    1979-01-01

    A diagnostic anatomical X-ray apparatus comprising a converter and a television camera for converting an X-ray image of a subject into a series of television fields of video signals is described in detail. A digital memory system stores and integrates the video signals over a time interval corresponding to a plurality of successive television fields. The integrated video signals are recovered from storage and fed to a digital or analogue subtractor, the resulting output being displayed on a television monitor. Thus the display represents on-going changes in the anatomical X-ray image. In a modification, successive groups of fields are stored and integrated in three memories, cyclically, and subtractions are performed between successive pieces of integrated signals to provide a display of successive alterations in the X-ray image. For investigations of the heart, the integrating interval should be of the order of one cardiac cycle. (author)

  3. Digital subtraction angiography in 105 living renal transplant donors

    International Nuclear Information System (INIS)

    Suh, Ho Jong; Oh, Kyung Seung; Kim, So Sun; Huh, Jin Do; Kim, Ho Joon; Chun, Byung Hee; Joh, Young Duck

    1989-01-01

    In order to analyze the number and length of the renal arteries and to evaluate abnormalities of the renal parenchyma and vessel, digital subtraction angiogram images of 105 potential renal donors (45 men and 60 women aged 17-66 years) were studied retrospectively. For the entire series, 31 donors had multiple renal arteries on one side (15 on the left, 11 on the right) and 5 donors on the both sides. 89 donors were family related either parents or siblings of recipients. The estimation of the length of the renal artery was based on the mean height of the second lumbar vertebral body (L2). The right renal artery is significant longer than on the left and measured more than the height of L2 vertebral body in 84 cases on the right and 60 cases on the left. Twenty two donors underwent right nephrectomy due to presence of multiple renal arteries on the left (N=14), proximal bifurcation of left main renal artery (N=3), and young females in reproductive age (N=5). Unexpected abnormalities found with angiogram were seen in 7 cases and they include renal artery stenosis (N=2), renal cysts (N=4) and focal infarction (N=1). In cases of the renal cysts and focal infarction, there were no serious complications related to the abnormalities. It is conclude that intra-arterial digital subtraction angiography is safe and efficient method to image renal anatomy of the potential renal donors

  4. Digital subtraction radiography evaluation of the bone repair process of chronic apical periodontitis after root canal treatment.

    Science.gov (United States)

    Benfica e Silva, J; Leles, C R; Alencar, A H G; Nunes, C A B C M; Mendonça, E F

    2010-08-01

    To monitor radiographically the progress of bone repair within chronic periapical lesions after root canal treatment using digital subtraction radiography (DSR). Twelve patients with 17 single-rooted teeth with chronic apical periodontitis associated with an infected necrotic pulp were selected for root canal treatment. Periapical radiographs were taken before treatment (baseline) and immediately post-treatment, 45, 90, 135 and 180 days after treatment. The radiographic protocol included the use of individualized film holders with silicone bite blocks. The six radiographic images were digitized and submitted to digital subtraction using DSR software, resulting in five subtracted images (SI). Quantitative analysis of these SI was performed using Image Tool software to assess pixel value changes, considering a step-wedge as the gold standard and a cut-off value of 128 pixels. The aim was to identify any increase or decrease in mineral density in the region of the periapical lesion. A minor decrease in mineral density at the canal filling session and a significant progressive mineral gain in the following evaluations (P < 0.001) occurred. Pairwise comparison of pixel grey values revealed that only the 180-day follow-up differed significantly from the previous SI. Digital subtraction radiography is a useful method for evaluating the progress of bone repair after root canal treatment. Noticeable mineral gain was observed approximately 90 days after root canal filling and definite bone repair after 180 days.

  5. The Sloan Digital Sky Survey-II Supernova Survey:Search Algorithm and Follow-up Observations

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao; /Pennsylvania U. /KIPAC, Menlo Park; Bassett, Bruce; /Cape Town U. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Cinabro, David; /Wayne State U.; DeJongh, Don Frederic; /Fermilab; Depoy, D.L.; /Ohio State U.; Doi, Mamoru; /Tokyo U.; Garnavich, Peter M.; /Notre Dame U.; Craig, Hogan, J.; /Washington U., Seattle, Astron. Dept.; Holtzman, Jon; /New Mexico State U.; Jha, Saurabh; /Stanford U., Phys. Dept.; Konishi, Kohki; /Tokyo U.; Lampeitl, Hubert; /Baltimore, Space; Marriner, John; /Fermilab; Miknaitis, Gajus; /Fermilab; Nichol, Robert C.; /Portsmouth U.; Prieto, Jose Luis; /Ohio State U.; Richmond, Michael W.; /Rochester Inst.; Schneider, Donald P.; /Penn State U., Astron. Astrophys.; Smith, Mathew; /Portsmouth U.; SubbaRao, Mark; /Chicago U. /Tokyo U. /Tokyo U. /South African Astron. Observ. /Tokyo

    2007-09-14

    The Sloan Digital Sky Survey-II Supernova Survey has identified a large number of new transient sources in a 300 deg2 region along the celestial equator during its first two seasons of a three-season campaign. Multi-band (ugriz) light curves were measured for most of the sources, which include solar system objects, Galactic variable stars, active galactic nuclei, supernovae (SNe), and other astronomical transients. The imaging survey is augmented by an extensive spectroscopic follow-up program to identify SNe, measure their redshifts, and study the physical conditions of the explosions and their environment through spectroscopic diagnostics. During the survey, light curves are rapidly evaluated to provide an initial photometric type of the SNe, and a selected sample of sources are targeted for spectroscopic observations. In the first two seasons, 476 sources were selected for spectroscopic observations, of which 403 were identified as SNe. For the Type Ia SNe, the main driver for the Survey, our photometric typing and targeting efficiency is 90%. Only 6% of the photometric SN Ia candidates were spectroscopically classified as non-SN Ia instead, and the remaining 4% resulted in low signal-to-noise, unclassified spectra. This paper describes the search algorithm and the software, and the real-time processing of the SDSS imaging data. We also present the details of the supernova candidate selection procedures and strategies for follow-up spectroscopic and imaging observations of the discovered sources.

  6. Combined nuclear and digital subtraction contrast arthrography in painful knee prosthesis

    International Nuclear Information System (INIS)

    Namasivayam, J.; Forrester, A.; Poon, F.W.; Cuthbert, G.F.; McKillop, J.H.; Bryan, A.S.

    1992-01-01

    The evaluation of a painful knee prosthesis remains a difficult problem for both orthopaedic surgeons and radiologists. We have compared digital subtraction arthrography with nuclear-arthrography in 7 patients with a painful knee prosthesis. Three patients showed a loose tibial component, demonstrated by both digital subtraction and nuclear arthrography. All 3 underwent revision of their prosthesis. One patient had an equivocal digital subtraction arthrogram and negative nuclear arthrogram, while both studies were negative in the 3 remaining patients. Nuclear arthrography is a simple procedure and can provide useful additional information when combined with digital subtraction arthrography. (orig.)

  7. Arthrography of painful hips following arthroplasty: Digital versus plain film subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Walker, C W; FitzRandolph, R L; Dalrymple, G V [Arkansas Univ. for Medical Sciences, Little Rock, AR (USA). Dept. of Radiology John McClellan Memorial Veterans Hospital, Little Rock, AR (USA); Collins, D N [Arkansas Univ. for Medical Sciences, Little Rock, AR (USA). Dept. of Orthopedics John McClellan Memorial Veterans Hospital, Little Rock, AR (USA)

    1991-08-01

    Digital and manual subtraction images obtained during the arthrographic evaluation of 78 painful hip prostheses were reviewed retrospectively. Revision arthroplasty was performed in 53 of these cases, and the arthrographic and surgical findings were correlated. The digital and manual subtraction images were evaluated without knowledge of the surgical results using established criteria for component loosening. The difference between detection of femoral component loosening on digital as opposed to manual subtraction images was statistically significant (P < 0.05). This study demonstrates that digital subtraction improves the evaluation of femoral component loosening in painful hip prostheses. (orig./GDG).

  8. Using a digital signal processor as a data stream controller for digital subtraction angiography

    International Nuclear Information System (INIS)

    Meng, J.D.; Katz, J.E.

    1991-10-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement local servo loops. We present an example of a DSP as an input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display

  9. Digital subtraction CT angiography for the detection of posterior inferior cerebellar artery aneurysms: comparison with digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Guo Zhong; Luo, Song; Zhou, Chang Sheng; Zhang, Long Jiang; Lu, Guang Ming [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China)

    2017-09-15

    To evaluate the diagnostic accuracy of digital subtraction CT angiography (DS-CTA) in detecting posterior inferior cerebellar artery (PICA) aneurysms with digital subtraction angiography (DSA) as reference standard. A total of 115 patients, including 56 patients diagnosed with PICA aneurysms by CTA or DSA and 59 non-PICA-aneurysm patients were included in this retrospective study. All patients underwent DS-CTA and DSA. The site of PICA aneurysms and the pattern of haemorrhage were analysed. Sensitivity and specificity of DS-CTA without and with combining haemorrhage pattern in diagnosing PICA aneurysms were evaluated on a per patient and per aneurysm basis with DSA. Of 115 patients, 56 patients (48.7%) had 61 PICA aneurysms (size range, 1.1-13.5 mm; mean size, 4.9 ± 2.8 mm) on DSA. The sensitivity and specificity in depicting PICA aneurysms were 89.3% and 96.6% on a per patient basis and 90.2% and 93.4% on a per aneurysm basis, while the corresponding values were 94.6% and 96.6% on a per patient basis and 95.1% and 93.4% on a per aneurysm basis when combining with haemorrhage site. DS-CTA has a high sensitivity and specificity in detecting PICA aneurysms compared with DSA. It may be helpful for clinical diagnosis of PICA aneurysms to combine with haemorrhage sites. (orig.)

  10. Predictive value of digital subtraction angiography in patients with tuberculous meningitis

    International Nuclear Information System (INIS)

    Rojas-Echeverri, L.A.; Soto-Hernandez, J.L.; Garza, S.; Martinez-Zubieta, R.; Miranda, L.I.; Garcia-Ramos, G.; Zenteno, M.

    1996-01-01

    Digital subtraction angiography (DSA) was performed in 24 adults with tuberculous meningitis (TBM) and results were correlated with 24 admission and 16 follow-up CT examinations. 19 MRI studies and clinical outcome at a mean follow-up of 44 weeks. DSA was abnormal in 11 patients. Abnormal DSA was associated with advenced clinical stages of the Medical Research Council classification, admission CT with hydrocephalus or gyral cortical enhancement. MRI disclosed brain infarcts not seen on initial CT in 8 cases. Of seven patients who died, 4 had abnormal and 3 normal DSA. Among patients who survived, those with normal DSA had a better functional outcome by Karnofsky scores. During follow-up infarcts were evident in 16 patients. Abnormal DSA in relation to brain infarcts had a sensitivity of 0.56, specificity 0.75, positive predictive value 0.82 and negative predictive value 0.46. A single arteriogram does not predict the outcome in patients with TBM and its value is limited in the assessment of vascular complications of TBM. Angiography in TBM is justified only in specific clinical trials to assess new therapeutic modalities against infarcts. (orig.)

  11. Intraarterial digital subtraction angiography applied to diagnosis of hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nishizawa, Sadahiko; Sano, Akira; Imanaka, Kazufumi; Sasai, Keisuke; Nagae, Toshiyuki; Mizutani, Masaru; Hatabu, Hiroto; Sadatou, Norihiro; Kuroda, Yasumasa

    1985-12-01

    This paper deals with diagnostic values of intraarterial digital subtraction angiography (IADSA) for evaluating hepatocellular carcinoma. The present series consists of 44 patients with hepatocellular carcinoma, who underwent IADSA combined with conventional hepatic angiography 67 times in total. The evaluated vessels by IADSA included 70 hepatic arteries and 36 portal veins. Comparative studies on the image quality of IADSA with conventional angiography were made in referring to the tumor stain for arteriograms and resolution of intrahepatic portal branches for portograms. Diagnostic superiority including equality of DSA image to conventional was noted in arteriograms: 72.7 % in the right lobe and 86 % in the left. Most deteriorated DSA images were caused by misregistration artifacts. IADSA portography revealed basically diagnostic values to demonstrate lobar, segmental or more peripheral branches in about 95 % of cases studied. DSA, characterized by high contrast resolution and real-time subtraction, offered important and effective informations for interventional angiography as well as resectability of the tumors, requiring less contrast medium.

  12. Motion compensation in digital subtraction angiography using graphics hardware.

    Science.gov (United States)

    Deuerling-Zheng, Yu; Lell, Michael; Galant, Adam; Hornegger, Joachim

    2006-07-01

    An inherent disadvantage of digital subtraction angiography (DSA) is its sensitivity to patient motion which causes artifacts in the subtraction images. These artifacts could often reduce the diagnostic value of this technique. Automated, fast and accurate motion compensation is therefore required. To cope with this requirement, we first examine a method explicitly designed to detect local motions in DSA. Then, we implement a motion compensation algorithm by means of block matching on modern graphics hardware. Both methods search for maximal local similarity by evaluating a histogram-based measure. In this context, we are the first who have mapped an optimizing search strategy on graphics hardware while paralleling block matching. Moreover, we provide an innovative method for creating histograms on graphics hardware with vertex texturing and frame buffer blending. It turns out that both methods can effectively correct the artifacts in most case, as the hardware implementation of block matching performs much faster: the displacements of two 1024 x 1024 images can be calculated at 3 frames/s with integer precision or 2 frames/s with sub-pixel precision. Preliminary clinical evaluation indicates that the computation with integer precision could already be sufficient.

  13. Real-time digital x-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.

    1982-01-01

    The invention provides a method of producing visible difference images derived from an X-ray image of an anatomical subject, comprising the steps of directing X-rays through the anatomical subject for producing an image, converting the image into television fields comprising trains of on-going video signals, digitally storing and integrating the on-going video signals over a time interval corresponding to several successive television fields and thereby producing stored and integrated video signals, recovering the video signals from storage and producing integrated video signals, producing video difference signals by performing a subtraction between the integrated video signals and the on-going video signals outside the time interval, and converting the difference signals into visible television difference images representing on-going changes in the X-ray image

  14. The digital subtraction technique in lateral urethrocystography. Die laterale Urethrozystographie in digitaler Subtraktionstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, K. (Radiologische Abt., Caritas-Krankenhaus, Bad Mergentheim (Germany)); Peterseim, H. (Frauenklinik, Caritas-Krankenhaus, Bad Mergentheim (Germany)); Grehn, S. (Radiologische Abt., Caritas-Krankenhaus, Bad Mergentheim (Germany))

    1994-09-01

    The first application of the digital subtraction technique to lateral urethrocystography is described. This methodology facilitates gynecological-urological operations by providing reliable investigation results and an unambiguous image interpretation. Methods and first experiences with the digital subtraction technique in gynecological-urological diagnosis are reported. (orig.)

  15. Incidence of ischemic lesions in diffusion-weighted imaging after transbrachial digital subtraction angiography

    International Nuclear Information System (INIS)

    Aschenbach, R.; Majeed, A.; Eger, C.; Basche, S.; Kerl, J.M.; Vogl, T.J.

    2008-01-01

    Purpose: to evaluate the frequency of ischemia after transbrachial digital subtraction angiography under ambulant conditions using diffusion-weighted imaging. Materials and methods: 200 patients were included in a prospective study design and received transbrachial digital subtraction angiography under ambulant conditions. Before and after digital subtraction angiography, diffusion-weighted imaging of the brain was performed. Results: in our study population no new lesions were found in diffusion-weighted imaging after digital subtraction angiography during the 3-hour window after angiography. One new lesion was found 3 days after angiography as a late onset complication. Therefore, the frequency of neurological complications is at the level of the confidence interval of 0 - 1.5%. Conclusion: the transbrachial approach under ambulant conditions is a safe method for digital subtraction angiography resulting in a low rate of ischemic lesions in diffusion-weighted imaging. (orig.)

  16. Evaluation of left ventricular function by digital subtraction angiography

    International Nuclear Information System (INIS)

    Kuribayashi, Sachio; Ootaki, Makoto; Matsuyama, Seiya; Kanemoto, Nariaki; Furuya, Hideo

    1985-01-01

    Effects of contrast medium doses on left ventriculographic images using intravenous digital subtraction angiography (IVDSA-LVG) were assessed. The validity of IVDSA-LVG in evaluating ejection fraction (FF) and left ventricular regional wall motion was determined by comparison with conventional left ventriculography using direct injection (direct LVG). The advantages of left ventriculography using intraarterial subtraction angiography (IADSA-LVG) performed by injecting small doses of contrast media directly into the left ventricle were stressed. 1. To assess the effects of doses of contrast media on IVDSA-LVG, 10, 20, and 30 ml Urografin-76 were injected into the superior vena cava in 16 patients, and the resulting images were compared in each patient. With only 10 ml contrast medium, left ventricular opacification was fairly good, and regional wall motion was evaluated in many cases, but 30 ml were needed to calculate ventricular volume and EF. 2. To determine the validity of IVDSA-LVG in evaluating EF and regional wall motion, we compared IVDSA-LVG using 30 ml of contrast medium with direct LVG in 18 patients. There was a good correlation between the two methods in determining EF (r = 0.877), and 90 % of the interpretations of regional wall motion were in agreement by the two methods. IVDSA-LVG was useful and accurate in evaluating EF and regional wall motion of the left ventricle. 3. IADSA-LVG was performed for five patients, and good quality images were obtained in many cases, even with relatively small doses (10 ml) of contrast media. These results suggested that this method may be used in cases with impaired LV function, to avoid hemodynamic derangement induced by conventional direct LVG using large doses of contrast medium. (author)

  17. Dermoscopy, Digital Dermoscopy and Other Diagnostic Tools in the Early Detection of Melanoma and Follow-up of High-risk Skin Cancer Patients.

    Science.gov (United States)

    Thomas, Luc; Puig, Susana

    2017-07-05

    Early detection is a key strategy for reducing the mortality and economic burden associated with melanoma. Dermoscopy is a non-invasive and cost-effective tool for melanoma diagnosis, which has been shown to be a reliable and sensitive method for detecting early-stage skin cancer and reducing the number of unnecessary excisions. Patients at high risk of developing melanoma require long-term surveillance. Use of digital dermoscopy follow-up of these patients has led to improved outcomes. Combined follow-up programmes using total-body photography and digital dermoscopy have led to further improvements in early diagnosis and diagnostic accuracy. Dermoscopy is now widely used by dermatologists, but the public health impact of this tool is yet to be evaluated. Despite the clear advantages of dermoscopy and digital follow-up meth-ods, dermoscopy training and access to digital dermoscopy among dermatologists and general practitioners needs to be improved.

  18. Image noise reduction algorithm for digital subtraction angiography: clinical results.

    Science.gov (United States)

    Söderman, Michael; Holmin, Staffan; Andersson, Tommy; Palmgren, Charlotta; Babic, Draženko; Hoornaert, Bart

    2013-11-01

    To test the hypothesis that an image noise reduction algorithm designed for digital subtraction angiography (DSA) in interventional neuroradiology enables a reduction in the patient entrance dose by a factor of 4 while maintaining image quality. This clinical prospective study was approved by the local ethics committee, and all 20 adult patients provided informed consent. DSA was performed with the default reference DSA program, a quarter-dose DSA program with modified acquisition parameters (to reduce patient radiation dose exposure), and a real-time noise-reduction algorithm. Two consecutive biplane DSA data sets were acquired in each patient. The dose-area product (DAP) was calculated for each image and compared. A randomized, blinded, offline reading study was conducted to show noninferiority of the quarter-dose image sets. Overall, 40 samples per treatment group were necessary to acquire 80% power, which was calculated by using a one-sided α level of 2.5%. The mean DAP with the quarter-dose program was 25.3% ± 0.8 of that with the reference program. The median overall image quality scores with the reference program were 9, 13, and 12 for readers 1, 2, and 3, respectively. These scores increased slightly to 12, 15, and 12, respectively, with the quarter-dose program imaging chain. In DSA, a change in technique factors combined with a real-time noise-reduction algorithm will reduce the patient entrance dose by 75%, without a loss of image quality. RSNA, 2013

  19. Radiation doses to patients from digital subtraction angiography

    International Nuclear Information System (INIS)

    Goni, H.; Tsalafoutas, I. A.; Tzortzis, G.; Pappas, P.; Bouzas, N.; Loulakas, J.; Georgiou, A.; Georgiou, E.; Yakoumakis, E. N.

    2005-01-01

    This investigation determined patient doses during digital subtraction angiography (DSA). Fluoroscopy time, dose-area product (DAP) and entrance surface air kerma (ESAK) were analysed from 263 DSA examinations, classified into seven categories: (1) abdominal aorta, iliac, femoral, popliteal and leg arteries; (2) abdominal aorta and super-selective DSA of renal arteries; (3) combination of (1) and (2); (4) super-selective DSA of common carotid and vertebral arteries, intracranial branches in face and profile projections; (5) super-selective DSA of hepatic, splenic, superior and inferior mesenteric arteries; (6) combination of (1) and (4); and (7) celiac trunk and branches. Median DAP values were 67.7, 92.9, 76.6, 53.6, 105.7, 76.1 and 2.6 Gy cm 2 , respectively. With the exception of one examination, ESAK values were below 2 Gy: the limit for erythema. Compared with published data, DAP values were within the range reported for (1) and (4), slightly larger for (2) and (5), whereas no references were identified for the remaining three categories. (authors)

  20. A case of aortitis syndrome diagnosed by digital subtraction angiography

    International Nuclear Information System (INIS)

    Tamaki, Atsushi; Sakai, Masashi; Yano, Kimio

    1984-01-01

    A 45-year-old female was admitted to our hospital with complaints of anemia, hypertension, and a dull, throbbing pain in the right side of the neck. On physical examination, a pulsating tumor in the right side of the neck and a ''to-and-fro'' murmur at the right 2nd intercostal space were noted. Laboratory tests revealed ESR 90 mm/hour and CRP 5+. Digital subtraction angiography (DSA) showed an aneurysm distal to the narrowing of the right common carotid artery, in addition to winding and narrowing of the right vertebral and the left common carotid arteries. These findings are typical of Type I aortitis syndrome. Aortogram showed aortic regurgitation (AR). Furthermore, we found the presence of HLA Bw52 and a conspicuous increase of tromboxane B 2 . Treatment involving a combination of prednisolone, azathioprine and estriol was effective, resulting in marked improvement of the patient's general condition as well as laboratory test results. In cases of aortitis syndrome combined with an aneurysm of a large artery and AR, direct opacification of the aorta with a catheter is occasionally hazardous and is difficult to perform repeatedly. DSA is useful in such circumstances because it can be performed repeatedly with little risk and it offers an image as clear as these obtained by direct injection of contrast medium in the aorta. (author)

  1. Robotic digital subtraction angiography systems within the hybrid operating room.

    Science.gov (United States)

    Murayama, Yuichi; Irie, Koreaki; Saguchi, Takayuki; Ishibashi, Toshihiro; Ebara, Masaki; Nagashima, Hiroyasu; Isoshima, Akira; Arakawa, Hideki; Takao, Hiroyuki; Ohashi, Hiroki; Joki, Tatsuhiro; Kato, Masataka; Tani, Satoshi; Ikeuchi, Satoshi; Abe, Toshiaki

    2011-05-01

    Fully equipped high-end digital subtraction angiography (DSA) within the operating room (OR) environment has emerged as a new trend in the fields of neurosurgery and vascular surgery. To describe initial clinical experience with a robotic DSA system in the hybrid OR. A newly designed robotic DSA system (Artis zeego; Siemens AG, Forchheim, Germany) was installed in the hybrid OR. The system consists of a multiaxis robotic C arm and surgical OR table. In addition to conventional neuroendovascular procedures, the system was used as an intraoperative imaging tool for various neurosurgical procedures such as aneurysm clipping and spine instrumentation. Five hundred one neurosurgical procedures were successfully conducted in the hybrid OR with the robotic DSA. During surgical procedures such as aneurysm clipping and arteriovenous fistula treatment, intraoperative 2-/3-dimensional angiography and C-arm-based computed tomographic images (DynaCT) were easily performed without moving the OR table. Newly developed virtual navigation software (syngo iGuide; Siemens AG) can be used in frameless navigation and in access to deep-seated intracranial lesions or needle placement. This newly developed robotic DSA system provides safe and precise treatment in the fields of endovascular treatment and neurosurgery.

  2. Intravenous digital subtraction angiography contrast media time-concentration curves

    International Nuclear Information System (INIS)

    Burbank, F.H.; Brody, W.R.

    1985-01-01

    At any specified radiation dose and system signal-to-noise ratio, temporal (masked-mode) intravenous digital subtraction angiography (IV-DSA) image quality is dependent upon the shape of the arterial time-concentration curve produced by the intravenous injection of iodinated contrast media. If contrast media appears in the arterial circulation as a compact bolus and reaches a high peak, images containing low or no iodine (the mask image or images) and high iodine concentration (the enhanced image or images) can be obtained close together in time, maximizing contrast media enhancement and minimizing the potential for spatial movement (misregistration). However, if the contrast media bolus is broad, rising slowly to a low concentration peak, sufficient time may pass for movement to occur and the opacification difference between the mask image and the enhanced image may be too small to visualize vessels of interest. Consequently, knowledge of the rules which govern the formation of time-concentration curves is central to IV-DSA

  3. Evaluation of left ventricular function using digital subtraction angiography

    International Nuclear Information System (INIS)

    Kozuka, Takahiro; Ohta, Mitsushige

    1985-01-01

    To evaluate function of the left ventricle and myocardial perfusion images, digital subtraction angiography (DSA) was performed in 45 patients with ischemic heart disease. Validity of the technique was compared with data obtained from cine left ventriculogram in all patients and 201 T1 myocardial images in 20 patients. End-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) calculated from DSA were correlated closely with those from cine left ventriculogram (r = 0.92, r = 0.94 and r = 0.86, respectively). Regional contractility at the antero-lateral wall of the left ventricle, assessed by DSA, was also correlated well with cine left ventriculogram (r = 0.75). Evaluation of the inferior wall motion showed less correlation in both procedures (r = 0.68). Phase and amplitude analysis with the same technique with radionuclide cardiac angiography was successfully applied in left ventriculogram obtained by DSA. The procedure seems to be helpful for objective evaluation of the left ventricular wall motion. Myocardial perfusion image, obtained with modified Radtke's technique, showed good coincidence with 201 T1 images. Thus, DSA is applicable for evaluation of function of the left ventricle and myocardial perfusion in patients with ischemic heart disease. (author)

  4. Experience with digital subtraction angiography of cervicocranial region

    International Nuclear Information System (INIS)

    Bohutova, J.; Neuwirth, J.; Kuncova, S.; Lerlova, L.

    1988-01-01

    Digital subtraction angiography (DSA) of the head was performed in 100 patients for mostly neurological indications, less frequently pathological processes in the region of the external carotid artery. The intravenous or intraarterial route was selected according to the condition and age of the patient and clinical diagnosis. In 55% of cases the contrast medium was administered into the ascending aorta, in 13% selectively into the carotid or vertebral arteries. The examination was performed intravenously in 32%, most frequently via inferior vena cava (26%). The visualization of the whole area of the carotid and vertebral arteries from the ramification of the aortal arc up to the periphery requires to make at least 4 to 5 administrations of contrast medium, since simultaneous representation of lateral and AP projection for DSA has not been so far possible and the screen size is small. In intravenous DSA the amount of contrast medium increases up to 200 ml. Instillation into the ascending artery is therefore preferred and half of the amount is thus sufficient. DSA has proved of advantage in the examination of patients with arteriosclerosis, angiomas and arteriovenous malformations, vascularized and avascular expansive processes in intracranial and extracranial localizations. Quality angiograms were obtained in 84%, those still suitable for evaluation in 14% and useless in 2% of cases. (author). 14 figs., 1 tab., 16 refs

  5. Digital subtraction arthrography in preoperative evaluation of painful total hip arthroplasty

    International Nuclear Information System (INIS)

    Ginai, A.Z.; Biezen, F.C. van; Kint, P.A.M.; Oei, H.Y.; Hop, W.C.J.

    1996-01-01

    Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or acetabular components. The operative findings acted as the gold standard. Digital subtraction arthrography was best for predicting a loose acetabular component, while no significant additional predictive value was found for plain radiographs and scintigraphy. Digital subtraction arthrography was also the most important modality for predicting a loose femoral component, while the plain radiograph was of significant additional value and scintigraphy was of no additional value on multivariate analysis. (orig./MG)

  6. Evaluation of intracranial arteriovenous malformations before and after embolization with dynamic MR digital subtraction angiography

    International Nuclear Information System (INIS)

    Chen Shuang; Feng Xiaoyuan; Baleriaux, D.; Metens, T.

    2005-01-01

    Objective: To evaluate the clinical utility and accuracy of dynamic MR digital subtraction angiography (MR-DSA) in the detection of intracranial arteriovenous malformations before and after embolization. Methods: A prospective blinded comparison of MR-DSA, 3D contrast-enhanced T 1 -weighted MR angiography (3D-CEMRA), proton-weighted imaging and conventional digital subtraction angiography (DSA) were underwent in 22 consecutive AVMs patients before and after embolization. Two readers independently interpreted images and compared with DSA images. Results: There was complete agreement between MR-DSA and DSA for classification and size of nidus before and after embolization in all cases. MR-DSA showed the modified hemodynamic features (the time of nidus, early venous enhancement delayed after carotid arteries appearance) in 17 cases, and nidus size were reduced in 13 cases (including 4 complete embolized cases) after embolization, which were 100% consistence compared with DSA. MR-DSA failed to depict 1 intranidal aneurysm and missed 1 less dilated artery and draining vein after embolization respectively, which were demonstrated clearly by 3D-CEMRA confirmed with DSA. The relatively more or less hyperintensity could be seen on proton-weighted imaging in all cases after embolization than before. Conclusion: MR-DSA is a fast, efficient, and noninvasive technique to provide hemodynamic information relevant for AVMs before and after embolization. Proton imaging is sensitive in delineation of the embolized region, MR-DSA, 3D-CEMRA and proton-weighted imaging should be combined in the evaluation and follow-up AVMs after partial embolization. (authors)

  7. A study on the geometric correction for the digital subtraction radiograph

    International Nuclear Information System (INIS)

    Lim, Suk Young; Koh, Kwang Joon

    2001-01-01

    To develop a new subtraction program for registering digital images based on the correspondence of anatomic structures. The digital periapical images were obtained by Digora system with Rinn XCP equipment after translation of 1-16 mm, and rotation of 2-20 at the premolar and molar areas of the human dried mandible. The new subtraction program, NIH Image program and Emago/Advanced program were compared by the peak-signal -to noise ratio (PSNR). The new subtraction program was superior to NIH Images program and Emago/Advanced program up to 16 mm translation and horizontal angulation up to 4. The new subtraction program can be used for subtracting digital periapical images

  8. Mental Computation or Standard Algorithm? Children's Strategy Choices on Multi-Digit Subtractions

    Science.gov (United States)

    Torbeyns, Joke; Verschaffel, Lieven

    2016-01-01

    This study analyzed children's use of mental computation strategies and the standard algorithm on multi-digit subtractions. Fifty-eight Flemish 4th graders of varying mathematical achievement level were individually offered subtractions that either stimulated the use of mental computation strategies or the standard algorithm in one choice and two…

  9. Will immediate postoperative imbalance improve in patients with thoracolumbar/lumbar degenerative kyphoscoliosis? A comparison between Smith-Petersen osteotomy and pedicle subtraction osteotomy with an average 4 years of follow-up.

    Science.gov (United States)

    Bao, Hongda; He, Shouyu; Liu, Zhen; Zhu, Zezhang; Qiu, Yong; Zhu, Feng

    2015-03-01

    A retrospective radiographical study. To compare compensatory behavior of coronal and sagittal alignment after pedicle subtraction osteotomy (PSO) and Smith-Petersen osteotomy (SPO) for degenerative kyphoscoliosis. There was a paucity of literature paying attention to the postoperative imbalance after PSO or SPO and natural evolution of the imbalance. A retrospective study was performed on 68 consecutive patients with degenerative kyphoscoliosis treated by lumbar PSO (25 patients) or SPO (43 patients) procedures at a single institution. Long-cassette standing radiographs were taken preoperatively, postoperatively, and at the last follow-up and radiographical parameters were measured. The lower instrumented vertebral level and level of osteotomy were compared between the patients with and without improvement. Negative sagittal vertical axis (SVA) was observed in the PSO group postoperatively, implying an overcorrection of SVA. This negative SVA improved spontaneously during follow-up (P imbalance (P = 0.027), whereas no difference in term of levels of osteotomy was found (P > 0.05). The overcorrection of SVA is more often seen in the PSO group. The coronal imbalance is more likely to occur in the SPO group. The postoperative sagittal imbalance often spontaneously improves with time. Lower instrumented vertebra at S1 or with pelvic fixation should be regarded as potential risk factors for persistent coronal imbalance in patients with SPO. 3.

  10. Digital subtraction radiographic evaluation of the standardize periapical intraoral radiographs

    International Nuclear Information System (INIS)

    Cho, Bong Hae; Nah, Kyung Soo

    1993-01-01

    The geometrically standardized intraoral radiographs using 5 occlusal registration material were taken serially from immediate, 1 day, 2, 4, 8, 12 and 16 weeks after making the bite blocks. The qualities of those subtracted images were evaluated to check the degree of reproducibility of each impression material. The results were as follows: 1. The standard deviations of the grey scales of the overall subtracted images were 4.9 for Exaflex, 7.2 for Pattern resin, 9.0 for Tooth Shade Acrylic, 12.2 for XCP only, 14.8 for Impregum. 2. The standard deviation of the grey scales of the overall subtracted images were grossly related to those of the localized horizontal line of interest. 3. Exaflex which showed the best subtracted image quality had 15 cases of straight, 14 cases of wave, 1 case of canyon shape. Impregum which showed the worst subtracted image quality had 4 cases of straight, 8 cases of wave, 18 cases of canyon shape respectively.

  11. Venous digital subtraction angiography for diagnosis of renal artery stenosis in arterial hypertony

    International Nuclear Information System (INIS)

    Schoerner, W.; Kempter, H.; Banzer, D.; Aviles, C.; Weiss, T.; Felix, R.

    1984-01-01

    Venous digital subtraction angiography was performed in 248 patients for the diagnosis of renal arterial stenosis. In 88% of the investigations the stenosis could be found. Comparison of digital angiography and conventional angiography was made for 57 renal arteries (25 investigations). In 52 renal arteries we found the same results with both methods, in 5 renal arteries we found the same results with both methods, in 5 renal arteries the digital angiography showed false positive results. The spatial resolution of digital subtraction angiography is sufficient for the correct diagnosis of significant renal arterial stenosis. With regard to the lower invasion of digital subtraction angiography compared to conventional angiography the first method should be used for clarification of renal arterial hypertension. (orig.)

  12. Diagnosis and evaluation of diseases of the hand by intravenous digital subtraction angiography done by an improved method

    International Nuclear Information System (INIS)

    Minakuchi, Kazuo; Nakamura, Kenji; Kudoh, Hiroaki; Takashima, Sumio; Manabe, Takao; Kaminoh, Toshio; Onoyama, Yasuto

    1988-01-01

    Twenty patients with various diseases of the hand were studied by intravenous digital subtraction angiography (IV-DSA). We used clay preparation as a compensatory filter to improve the radiological conditions and increased local circulation by use of a hot compress. By IV-DSA done in this way, excellent or good images of the carpal arteries were obtained in 21 of 23 hands examined (91%). For the metacarpal region, images were excellent or good for 13 hands (57%), and for the digital region, for 4 (17%). The arteries of the hand could be seen in all studies, although sometimes the image was poor. Further improvements of images by IV-DSA should make it possible to use IV-DSA for screening and follow-up studies of many parts of the body. (author)

  13. 3D printing of intracranial aneurysm based on intracranial digital subtraction angiography and its clinical application.

    Science.gov (United States)

    Wang, Jian-Li; Yuan, Zi-Gang; Qian, Guo-Liang; Bao, Wu-Qiao; Jin, Guo-Liang

    2018-06-01

    The study aimed to develop simulation models including intracranial aneurysmal and parent vessel geometries, as well as vascular branches, through 3D printing technology. The simulation models focused on the benefits of aneurysmal treatments and clinical education. This prospective study included 13 consecutive patients who suffered from intracranial aneurysms confirmed by digital subtraction angiography (DSA) in the Neurosurgery Department of Shaoxing People's Hospital. The original 3D-DSA image data were extracted through the picture archiving and communication system and imported into Mimics. After reconstructing and transforming to Binary STL format, the simulation models of the hollow vascular tree were printed using 3D devices. The intracranial aneurysm 3D printing simulation model was developed based on DSA to assist neurosurgeons in aneurysmal treatments and residency training. Seven neurosurgical residents and 15 standardization training residents received their simulation model training and gave high assessments for the educational course with the follow-up qualitative questionnaire. 3D printed simulation models based on DSA can perfectly reveal target aneurysms and help neurosurgeons select therapeutic strategies precisely. As an educational tool, the 3D aneurysm vascular simulation model is useful for training residents.

  14. Do We Still Have a Digital Divide in Mental Health? A Five-Year Survey Follow-up.

    Science.gov (United States)

    Robotham, Dan; Satkunanathan, Safarina; Doughty, Lisa; Wykes, Til

    2016-11-22

    Nearly everyone in society uses the Internet in one form or another. The Internet is heralded as an efficient way of providing mental health treatments and services. However, some people are still excluded from using Internet-enabled technology through lack of resources, skills, and confidence. Five years ago, we showed that people with severe mental illness were at risk of digital exclusion, especially middle-aged patients with psychosis and/or people from black or minority ethnic groups with psychosis. An understanding of the breadth of potential digital exclusion is vital for the implementation of digital health services. The aim of this study is to understand the context of digital exclusion for people who experience mental illness. We conducted a survey involving people with a primary diagnosis of psychosis or depression in London, United Kingdom. A total of 241 participants were recruited: 121 with psychosis and 120 with depression. The majority of surveys were collected face-to-face (psychosis: n=109; depression: n=71). Participants answered questions regarding familiarity, access, use, motivation, and confidence with Internet-enabled technologies (ie, computers and mobile phones). Variables predicting digital exclusion were identified in regression analyses. The results were compared with the survey conducted in 2011. Digital exclusion has declined since 2011. Online survey collection introduced biases into the sample, masking those who were likely to be excluded. Only 18.3% (20/109) of people with psychosis in our sample were digitally excluded, compared with 30% (28/93) in 2011 (χ 2 1 =3.8, P=.04). People with psychosis had less confidence in using the Internet than people with depression (χ 2 1 =7.4, P=.004). Only 9.9% (24/241) of participants in the total sample were digitally excluded, but the majority of these people had psychosis (n=20). Those with psychosis who were digitally excluded were significantly older than their included peers (t 30 =3

  15. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Young Ho; Kim, Kyung Soo; Jin, Hyun Seok; Hong, Kyung Won; Oh, Berm Seok; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, Kyung Hee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    2009-03-15

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 {mu}m and the range of lesional area was 36.95-138.52 mm{sup 2}. The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  16. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    International Nuclear Information System (INIS)

    Park, Jong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Young Ho; Kim, Kyung Soo; Jin, Hyun Seok; Hong, Kyung Won; Oh, Berm Seok; Park, Hun Kuk; Choi, Yong Suk; Hwang, Eui Hwan

    2009-01-01

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52 mm 2 . The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  17. Deblurring in digital tomosynthesis by iterative self-layer subtraction

    Science.gov (United States)

    Youn, Hanbean; Kim, Jee Young; Jang, SunYoung; Cho, Min Kook; Cho, Seungryong; Kim, Ho Kyung

    2010-04-01

    Recent developments in large-area flat-panel detectors have made tomosynthesis technology revisited in multiplanar xray imaging. However, the typical shift-and-add (SAA) or backprojection reconstruction method is notably claimed by a lack of sharpness in the reconstructed images because of blur artifact which is the superposition of objects which are out of planes. In this study, we have devised an intuitive simple method to reduce the blur artifact based on an iterative approach. This method repeats a forward and backward projection procedure to determine the blur artifact affecting on the plane-of-interest (POI), and then subtracts it from the POI. The proposed method does not include any Fourierdomain operations hence excluding the Fourier-domain-originated artifacts. We describe the concept of the self-layer subtractive tomosynthesis and demonstrate its performance with numerical simulation and experiments. Comparative analysis with the conventional methods, such as the SAA and filtered backprojection methods, is addressed.

  18. [Development of a digital chest phantom for studies on energy subtraction techniques].

    Science.gov (United States)

    Hayashi, Norio; Taniguchi, Anna; Noto, Kimiya; Shimosegawa, Masayuki; Ogura, Toshihiro; Doi, Kunio

    2014-03-01

    Digital chest phantoms continue to play a significant role in optimizing imaging parameters for chest X-ray examinations. The purpose of this study was to develop a digital chest phantom for studies on energy subtraction techniques under ideal conditions without image noise. Computed tomography (CT) images from the LIDC (Lung Image Database Consortium) were employed to develop a digital chest phantom. The method consisted of the following four steps: 1) segmentation of the lung and bone regions on CT images; 2) creation of simulated nodules; 3) transformation to attenuation coefficient maps from the segmented images; and 4) projection from attenuation coefficient maps. To evaluate the usefulness of digital chest phantoms, we determined the contrast of the simulated nodules in projection images of the digital chest phantom using high and low X-ray energies, soft tissue images obtained by energy subtraction, and "gold standard" images of the soft tissues. Using our method, the lung and bone regions were segmented on the original CT images. The contrast of simulated nodules in soft tissue images obtained by energy subtraction closely matched that obtained using the gold standard images. We thus conclude that it is possible to carry out simulation studies based on energy subtraction techniques using the created digital chest phantoms. Our method is potentially useful for performing simulation studies for optimizing the imaging parameters in chest X-ray examinations.

  19. Procedures for imaging of hemodialysis fistulas with particular reference to digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Neufang, K.F.R.; Erasmi-Koerber, H.; Wimmer, G.; Koeln Univ.

    1983-01-01

    All angiographic procedures established for imaging of hemodialysis fistulas, such as direct venous angiography, intravenous subtraction angiography and arteriography by direct puncture of the brachial artery of by Seldinger's transfemoral technique, can also be effected with digital image processing. Depending on the angiographic technique, the use of digital subtraction angiography has several advantages: lower doses and concentrations of the contrast agent, lower risk of complications (thrombosis of the fistula, vasospasm) and freedom from pain. In addition, there is a marked reduction of examination time and film cost. (orig.)

  20. Imaging of the digital arteries: Digital subtraction angiography versus conventional angiography

    International Nuclear Information System (INIS)

    Menanteau, B.P.; Treutenaere, J.M.; Marcus, C.; Ladam, V.; Gausserand, F.

    1986-01-01

    The authors report their experience with the use of digital subtraction angiography (DSA) and conventional angiography of the hand. Of the 95 patients in the study group, 80 underwent conventional angiography and 15 underwent DSA. They analyzed the studies with regard to the type and amount of contrast agent used, the number of radiographs needed, and the diagnostic quality of the images. Conventional angiography often requires general anesthesia, magnification, and pharmaco-angiographic techniques to improve the image-based diagnosis. In comparison with conventional angiography, intraarterial DSA is characterized by improved contrast sensitivity and inferior spatial resolution. However, DSA provides images as acceptable as those of conventional angiography. Smaller catheters can be used, and the examination is performed under local anesthesia. The authors conclude that intraarterial DSA is now the technique of choice for examining patients with chronic ischemia of the hand

  1. Long-term Clinical and Radiographic Outcomes of Pedicle Subtraction Osteotomy for Fixed Sagittal Imbalance: Does Level of Proximal Fusion Affect the Outcome? Minimum 5-Year Follow-up.

    Science.gov (United States)

    Yagi, Mitsuru; King, Akilah B; Cunningham, Matthew E; Boachie-Adjei, Oheneba

    2013-03-01

    Retrospective case series of surgically treated adult patients with fixed sagittal imbalance. To assess clinical and radiographic changes after pedicle subtraction osteotomy (PSO) to treat adult fixed sagittal imbalance. Although recent reports have shown favorable clinical outcomes for PSO, few reports have published long-term follow-up outcomes. It is also unknown whether long-term outcomes are correlated with the level of proximal fusion and the radiographic changes that are observed after PSO. We reviewed the charts, X-rays, and postoperative SRS-22 and Oswestry Disability Index (ODI) scores of 32 adult patients who presented with fixed sagittal imbalance and were treated with lumbar PSO. Long fusions were defined as those proximal to T6, and short fusions were defined as those below T8. Measured radiographic parameters included thoracic kyphosis, lumbar lordosis (LL), sacral slope, pelvic incidence, and sagittal balance (SVA). Statistical analysis included Student t test and chi-square test. A p value of imbalance, PSO provided good sagittal balance and maintained favorable clinical outcomes in both the short and long fusion groups despite a slight decrease in the SVA and a high complication rate. The data suggest that the loss of sagittal balance may be attributed to increase global and junctional kyphosis in short fusion groups, and should be monitored for long-term outcomes. Particular attention should be paid to the long-term deterioration of the SVA in adults who present with fixed sagittal imbalance after PSO. Copyright © 2013 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

  2. The contribution of chemical shift imaging with digital subtracting images to the diagnosis of steatohepatitis

    International Nuclear Information System (INIS)

    Guo Xinghua; Wang Juanping; Zhang Chongjie; Zheng Guofang; Fan Ruiqiang; Zhu Sumei; Liu Qiwang

    2006-01-01

    Objective: To investigate the diagnosis value of chemical shift imaging with digital subtracting in steatohepatitis. Methods: The in-phase images were subtracted by the out-phase ones in 34 cases of steatohepatitis, and the CNR were measured on these subtracted images to estimate the steatosis of the liver. The relationship of CT grade of steatohepatitis and CNR from the subtracted images was analyzed to evaluate the relationship between CNR and the degree of hepatic steatosis. The sensitivity and specificity of the subtracting and eyeballing methods were compared with chi-square test. Results: On the subtracted images, the liver and spleen were seen nearly the same aspects as low signals, CNR=0.98±0.06, meanwhile the spongy vertebra and the subcutaneous or abdominal lipid were seen as obvious higher signals in 52 normal cases. On the 34 steatohepatitis, scattered high signals were seen in the liver, which made the signal of liver higher than that of spleen, CNR=3.25±0.91--14.35±6.10. There was positive correlation between CNR and CT grade in the 34 cases of steatohepatitis, r=0.893, P<0.01. The sensitivity and specificity of the subtracting method were 88.24% and 94. 23%, significantly higher than that of the eyeballing results, 32.35% and 80.77%, P<0.01 and P<0.05. Conclusion: Chemical shift imaging with digital subtracting is a sensitive, specific, objective method to diagnose steatohepatitis and it is of potential ability for quantitative diagnosis. (authors)

  3. Digital subtraction angiography (DSA) for acute pulmonary emboli

    International Nuclear Information System (INIS)

    Witte, H.; Grabbe, E.; Buecheler, E.

    1983-01-01

    The results of 49 DSAs (in 29 patients) are presented; these were performed for the diagnosis or follow-up of pulmonary emboli. The direct or indirect signs of pulmonary emboli, known to occur during conventional pulmonary angiography, were used as diagnostic criteria. In 47 examinations it was possible to make or to exclude the diagnosis unequivocally. The advantages of DSA make it desirable to use this method as the first form of examination in the diagnosis of acute, but not immediately life-threatening, pulmonary emboli. (orig.) [de

  4. Usefulness of selective cerebral intra-arterial digital subtraction angiography by transbrachial approach

    International Nuclear Information System (INIS)

    Matsunaga, Naofumi; Hayashi, Kuniaki; Uetani, Masataka; Hirao, Koichi; Fukuda, Toshio; Aikawa, Hisayuki; Iwao, Masaaki; Hombo, Zen-ichiro

    1988-01-01

    Selective cerebral intra-arterial digital subtraction angiography (IA-DSA) by the transbrachial approach was performed on 53 patients (including 34 outpatients) with suspected cerebrovascular diseases or brain tumors. 80-cm-long, 4F modified Simmons catheter was used. Success rates of selective catheterization to the common carotid and vertebral arteries were 86.0 % from right transbrachial approach (35 cases) and 79.6 % from left approach (18 cases). Successful catheterization to the common carotid and ipsilateral vertebral arteries is obtained in 91.3 % from right transbrachial approach, and 78.7 % from left approach. Righ common carotid artery could be catheterized in all 55 cases from right transbrachial approach, but in only 6 of 15 patients (40 %) from left approach. As for contrast material, 4 or 6 ml of Iopamidol 300 mgI/ml were mechanically injected into common carotid artery at a flow rate of 2 - 3 ml/sec, and 9 ml two-fold diluted Iopamidol were injected into the vertebral artery at a flow rate of 6 ml/sec. There was no recoil of the catheter. Visualization of the relatively small vessels such as cortical branches was excellent in most cases. However, smaller vessel such as meningohypophyseal trunk was not well visualized with IA-DSA. Spatial resolution of IA-DSA was generally satisfactory. However, conventional angiography was still required, particularly to clearly delineate small cerebral aneurysms. Major complications were never experienced. It was concluded that this procedure is useful, particularly for the screening and postoperative follow-up studies, and can also be applied to outpatients. (author)

  5. Preliminary study of lateral cerebral angiography with reverse rotation in the digital image registration and subtraction

    International Nuclear Information System (INIS)

    Shen Zhenglin; Liu Dongyang; Shen Zhenghai; Li Shuping; Zhang Ziyan; Wu Yongjuan; Liu Peijun

    2012-01-01

    Objective: Investigate the value and feasibility of image registration with reverse rotation in lateral cerebral DSA. Methods: (1) Experimental study: the target images were subtracted directly, and subtracted again after reverse rotation. Software of registration and subtraction with reverse rotation edited by the author utilizing Visual Basic. The function of the automatic angle detection by the software were evaluated to see whether it detected the angle of line. The subtraction function of DSA by the software was evaluated. (2) Clinical retrospective study: the untreated mask and target images of 15 patients with motion along vertical axis during lateral cerebral DSA were uploaded to the software. The target images were processed with and without the software to get two sets of images. (3) Evaluation: four experienced radiologists read and compared the two sets of the images,and graded their findings. Results: (1) The automatic detection by the software suggested that the target images should be rotated counterclockwise 1.3°. The subtraction result of the software was satisfactory. (2) In the 15 sets of images, there were only three sets of images deemed optimal after traditional subtraction. After reverse rotation, artifacts were significantly reduced and the image sharper. There were ten cases with significant artifacts after traditional subtraction, and those images were sharper and showed more peripheral vessels after reverse rotation. The traditional subtraction images of two sets could not be interpreted,the reverse rotation registration images reached the diagnostic quality. (3) Subjective evaluation: there were more information and less noise and distortion in the registration images with reverse rotation than in the traditional subtraction. But the image resolution decreased slightly after reverse rotation registration. Conclusion: The registration of digital angiography with reverse rotation can improve the image quality in lateral cerebral DSA

  6. Two-step digit-set-restricted modified signed-digit addition-subtraction algorithm and its optoelectronic implementation.

    Science.gov (United States)

    Qian, F; Li, G; Ruan, H; Jing, H; Liu, L

    1999-09-10

    A novel, to our knowledge, two-step digit-set-restricted modified signed-digit (MSD) addition-subtraction algorithm is proposed. With the introduction of the reference digits, the operand words are mapped into an intermediate carry word with all digits restricted to the set {1, 0} and an intermediate sum word with all digits restricted to the set {0, 1}, which can be summed to form the final result without carry generation. The operation can be performed in parallel by use of binary logic. An optical system that utilizes an electron-trapping device is suggested for accomplishing the required binary logic operations. By programming of the illumination of data arrays, any complex logic operations of multiple variables can be realized without additional temporal latency of the intermediate results. This technique has a high space-bandwidth product and signal-to-noise ratio. The main structure can be stacked to construct a compact optoelectronic MSD adder-subtracter.

  7. [Follow-up of surgical biopsies in microcalcifications of the breast. Comparative analysis of patients submitted to mammography and digitalization of mammographic images].

    Science.gov (United States)

    Rulli, A; Cirocchi, R; Vento, A R; Naninato, P; Zanetti, A; Carli, L

    1997-01-01

    Improvements in the techniques of preoperative needle localization of nonpalpable breast lesions that have been detected at mammography, coupled with surgical biopsy of smaller volumes of breast tissue and the use of local anesthesia have produced a more aggressive attitude toward early biopsy of lesions that are suspected of malignancy. The authors report the follow-up in 92 cases, who underwent breast biopsy for microcalcifications with no palpable lesions. In 46 women the presence of microcalcifications was evaluated through a computerized instrument which allows digitalization of the image.

  8. Role of digital tomosynthesis and dual energy subtraction digital radiography in detecting pulmonary nodules

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sarvana G. [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Garg, Mandeep Kumar, E-mail: gargmandeep01@gmail.com [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Khandelwal, Niranjan; Gupta, Pankaj [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Gupta, Dheeraj; Aggarwal, Ashutosh Nath [Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Bansal, Subash Chand [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India)

    2015-07-15

    Highlights: • Accuracy of digital tomosynthesis for nodule detection is substantially higher. • Improvement in diagnostic accuracy is most pronounced for nodules <10 mm. • There is five times increase in radiation dose compared to DR. - Abstract: Objective: Digital tomosynthesis (DT) and dual-energy subtraction digital radiography (DES-DR) are known to perform better than conventional radiography in the detection of pulmonary nodules. Yet the comparative diagnostic performances of DT, DES-DR and digital radiography (DR) is not known. The present study compares the diagnostic performances of DT, DES-DR and DR in detecting pulmonary nodules. Subjects and methods: The institutional Review Board approved the study and informed written consent was obtained. Fifty-five patients (30 with pulmonary nodules, 25 with non-nodular focal chest pathology) were included in the study. DT and DES-DR were performed within14 days of MDCT. Composite images acquired at high kVp as part of DES-DR were used as DR images. Images were analyzed for presence of nodules and calcification in nodules. Interpretations were assigned confidence levels from 1 to 5 according to Five-Point rating scale. Areas under the receiver operating characteristic curves were compared using Z test. Results: A total of 110 (88 non-calcified, 22 calcified) nodules were identified on MDCT. For detection of nodules, DR showed cumulative sensitivity and specificity of 25.45% and 67.97%, respectively. DT showed a cumulative sensitivity and specificity of 60.9% and 85.07%, respectively. The performance was significantly better than DR (p < 0.003). DES-DR showed sensitivity and specificity of 27.75% and 82.64%, not statistically different from those of DR (p—0.92). In detection of calcification, there was no statistically significant difference between DT, DES-DR and DR. Conclusions: DT performs significantly better than DES-DR and DR at the cost of moderate increase in radiation dose.

  9. Digital subtraction angiography and intraarterial contrast medium injection for coronary examinations

    Energy Technology Data Exchange (ETDEWEB)

    Tobio, R; Kallmeyer, C; Castello, J

    1985-01-01

    Digital subtraction angiography (DSA) is an established method of vasography, most extensively used as i.v. DSA. Intraarterial injection, however, applying selective or non-selective contrast medium injection, seems to be at least as important a technique although it has not yet met with corresponding interest. The article explains advantages of the technique for angiographic examinations, in particular of coronary angiography.

  10. Digital subtraction angiography - a new approach to brain death determination in the newborn

    International Nuclear Information System (INIS)

    Albertini, A.; Schonfeld, S.; Hiatt, M.; Hegyi, T.

    1993-01-01

    The diagnosis of brain death in the newborn infants is elusive and often difficult. The lack of cerebral blood flow has become an identified criterion for loss of cerebral function. The diagnosis can be obtained by the technique of digital subtraction angiography, which is presented in two case reports demonstrating the utility of this technique. (orig.)

  11. The role of contrast-enhanced digital subtraction MRI in the diagnosis of vertebral metastasic tumors

    International Nuclear Information System (INIS)

    Xiao Yeyu; Yang Jun; Qi Weili; Liu Qize; Hong Bikai; Wu Renhua

    2008-01-01

    Objective: To evaluate the contrast-enhanced digital subtraction MRI in the diagnosis of vertebral metastasic tumors. Methods 66 vertebral metastasic tumors in 43 patients were examined with conventional MRI (T 1 WI, STIR and Contrast-enhanced T 1 WI) and contrast-enhanced digital subtraction MR imaging. All lesions were histologically proved. The quantity and characteristic imaging signs (including spiculation, bull eye sign and irregular edge) of lesions were detected separately by different sequences. K independent samples test was used. Results: The detection rates of 35 vertebral metastasic tumors with vertebral morphological changes were same in all MR sequences. But in the other 31 lesions without vertebral morphological changes, the detection rates were different and STIR was the highest in all sequences. Contrast-enhanced digital subtraction MRI was more sensitive than all the conventional MR sequences in finding characteristic imaging signs with statistically significant differences. Conclusion: Contrast enhanced subtraction MRI is an useful and convenient technique which has great value in finding vertebral metastasic tumors and depicting the characteristic imaging signs. (authors)

  12. Pediatric head and neck lesions: assessment of vascularity by MR digital subtraction angiography.

    Science.gov (United States)

    Chooi, Weng Kong; Woodhouse, Neil; Coley, Stuart C; Griffiths, Paul D

    2004-08-01

    Pediatric head and neck lesions can be difficult to characterize on clinical grounds alone. We investigated the use of dynamic MR digital subtraction angiography as a noninvasive adjunct for the assessment of the vascularity of these abnormalities. Twelve patients (age range, 2 days to 16 years) with known or suspected vascular abnormalities were studied. Routine MR imaging, time-of-flight MR angiography, and MR digital subtraction angiography were performed in all patients. The dynamic sequence was acquired in two planes at one frame per second by using a thick section (6-10 cm) selective radio-frequency spoiled fast gradient-echo sequence and an IV administered bolus of contrast material. The images were subtracted from a preliminary mask sequence and viewed as a video-inverted cine loop. In all cases, MR digital subtraction angiography was successfully performed. The technique showed the following: 1) slow flow lesions (two choroidal angiomas, eyelid hemangioma, and scalp venous malformation); 2) high flow lesions that were not always suspected by clinical examination alone (parotid hemangioma, scalp, occipital, and eyelid arteriovenous malformations plus a palatal teratoma); 3) a hypovascular tumor for which a biopsy could be safely performed (Burkitt lymphoma); and 4) a hypervascular tumor of the palate (cystic teratoma). Our early experience suggests that MR digital subtraction angiography can be reliably performed in children of all ages without complication. The technique provided a noninvasive assessment of the vascularity of each lesion that could not always have been predicted on the basis of clinical examination or routine MR imaging alone.

  13. A technique of scatter and glare correction for videodensitometric studies in digital subtraction videoangiography

    International Nuclear Information System (INIS)

    Shaw, C.G.; Ergun, D.L.; Myerowitz, P.D.; Van Lysel, M.S.; Mistretta, C.A.; Zarnstorff, W.C.; Crummy, A.B.

    1982-01-01

    The logarithmic amplification of video signals and the availability of data in digital form make digital subtraction videoangiography a suitable tool for videodensitometric estimation of physiological quantities. A system for this purpose was implemented with a digital video image processor. However, it was found that the radiation scattering and veiling glare present in the image-intensified video must be removed to make meaningful quantitations. An algorithm to make such a correction was developed and is presented. With this correction, the videodensitometry system was calibrated with phantoms and used to measure the left ventricular ejection fraction of a canine heart

  14. Digital image comparison by subtracting contextual transformations—percentile rank order differentiation

    Science.gov (United States)

    Wehde, M. E.

    1995-01-01

    The common method of digital image comparison by subtraction imposes various constraints on the image contents. Precise registration of images is required to assure proper evaluation of surface locations. The attribute being measured and the calibration and scaling of the sensor are also important to the validity and interpretability of the subtraction result. Influences of sensor gains and offsets complicate the subtraction process. The presence of any uniform systematic transformation component in one of two images to be compared distorts the subtraction results and requires analyst intervention to interpret or remove it. A new technique has been developed to overcome these constraints. Images to be compared are first transformed using the cumulative relative frequency as a transfer function. The transformed images represent the contextual relationship of each surface location with respect to all others within the image. The process of differentiating between the transformed images results in a percentile rank ordered difference. This process produces consistent terrain-change information even when the above requirements necessary for subtraction are relaxed. This technique may be valuable to an appropriately designed hierarchical terrain-monitoring methodology because it does not require human participation in the process.

  15. Digital video subtraction fluorography (DVSF) in the diagnosis of bronchial abnormality associated with congenital heart diseases

    International Nuclear Information System (INIS)

    Sano, Tetsuya; Arisawa, Jun; Nakajima, Toru

    1990-01-01

    To assess bronchial morphology and abnormality, 14 children with congenital heart diseases including 2 postoperative patients (age, 2 m.-4 yr) were studied by digital video subtraction fluorography (DVSF) using digital subtraction and image processing system (Philips, DVI-2). This newly developed technique clearly defined bronchial anatomy in all 14 patients. Bronchial situs could be determined in all 8 patients with complex heart anomalies. Out of 8 patients with respiratory distress in this study, obvious bronchial stenosis or obstruction was found by DVSF in 5 patients. Thus, DVSF image defined anatomies of main and lobar bronchi more clearly than previous noninvasive methods. Moreover, DVSF is noninvasive and easily performed even for small infants and critically ill patients. In conclusion, DVSF may be a useful technique to assess bronchial morphology and abnormality in patients with congenital heart diseases. (author)

  16. Imaging of the ventricular septal wall and the portal vein by digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Kyoichi; Harashima, Haruhiko; Yamada, Hiromi; Hiraishi, Takahisa; Mikami, Fumio [National Medical Center of Hospital, Tokyo (Japan)

    1983-06-01

    Digital subtraction angiography (DSA) was performed in 2 cases of hypertrophic cardiomyopathy and 2 cases of portal vein disorder. In hypertrophic cardiomyopathy, DSA with the infusion of isopaque 370 at the speed of 5 to 7 ml/sec produced the image of the ventricular septal wall, showing a small ejection fraction. Of portal vein disorders, DSA revealed the portal vein and was helpful in diagnosing tumoral thrombosis of the portal vein in a case of liver carcinoma and portal hypertension.

  17. Intra-arterial digital subtraction angiography in the diagnosis of insulinomas

    International Nuclear Information System (INIS)

    Moulopoulou, A.; Vlahos, L.

    1988-01-01

    Two cases of surgically proved benign insulinoma of the pancreas were correctly localized with intra-arterial digital subtraction angiography (IA-DSA) of the coeliac and the superior mesenteric artery, while the respective dynamic computed tomography (CT) and ultrasound (US) examinations were negative. In a third case of organic hyperinsulinism, IA-DSA, CT and US suggested a pancreatic islet-cell tumor, but the histological examination of the resected suspicious area was that of focal hyperplasia. 17 refs.; 3 figs

  18. Use of the digital subtraction angiography in the study of aortic dissecting aneurisms

    Energy Technology Data Exchange (ETDEWEB)

    Orlacchio, A; Fanucci, E; Pocek, M; Cirillo, F

    1984-01-01

    Authors on the basis of their data discuss the opportunity affered by the digital subtraction angiography (DSA) in the study of the aorta dissecting aneurisms. DSA as a consequence of the image formation and processing techniques allows the optimization of information concerning the reflux kinetics in the true and false lumen and offers a vascular mapping of the body district under study which is enough indicative to the subsequent therapy.

  19. The use of intravenous digital subtraction angiography in evaluating patients with complex congenital heart disease

    International Nuclear Information System (INIS)

    Moodie, D.S.

    1986-01-01

    The author previously described his experience in 450 patients with congenital heart disease using intravenous digital subtraction angiography (DSA) to define cardiac anatomy. He has been impressed by the utility of DSA in the evaluation of patients with congenital heart disease. It is now an integral part of his clinical practice to perform intravenous DSA studies both pre- and postoperatively on an inpatient as well as outpatient basis. This chapter details his DSA experience with complex forms of congenital heart disease

  20. Intraarterial digital subtraction angiography in bronchogenic carcinoma treated with bronchial artery infusion

    International Nuclear Information System (INIS)

    Gao-Jun Teng; Xi-Lei Chai; Guang-Ru Gao; Cheng-Fong Chu; Xian-Guang Zhou; Zhu-Yi Zhang; Ru-Li Xiang

    1991-01-01

    Intra-arterial digital subtraction angiography (IADSA) has been used with advantage for control of the results of bronchial artery infusion of drugs for primarily unresectable bronchogenic carcinoma. The IADSA has been performed as road mapping prior to therapy. Drug treatment has been performed with 4 different regimes, depending on tumour type. Debulking and in some cases complete healing are the results, which are superior to other reported treatments. (author). 7 refs.; 4 figs.; 3 tabs

  1. Treatment and Follow Up

    Science.gov (United States)

    ... Close Celiac Disease Understanding Celiac Disease What is Celiac Disease? Symptoms Screening and Diagnosis Treatment and Follow-Up Dermatitis ... you find the right healthcare practitioner to discuss symptoms, diagnose, and ... Our nationwide Healthcare Practitioner Directory lists primary care ...

  2. Detection of aneurysms in subarachnoidal hemorrhage - CT-angiography versus digital subtraction angiography

    International Nuclear Information System (INIS)

    Roehnert, W.; Haenig, V.; Hietschold, V.; Abolmaali, N.

    1998-01-01

    Purpose: The value of CT-angiography (CT-A) for the visualization of intracranial aneurysms was more closely defined by comparison with digital subtraction angiography (DSA). Methods: Over a period of 18 months a total of 106 patients in whom a subarachnoidal hemorrhage had been detected on native CT were examined in parallel by spiral CT and DSA. CT-angiography was performed under standardized parameters and included processing with 3D surface reconstructions. Results: In 64 patients (60.4%) at total of 72 aneurysms were detected. In four cases (6.2%) there were two and in two cases (3.1%) even three aneurysms. The findings of DSA and CTA agreed in 98 cases (92.5%). In four patients (3.8%) a false negative results was obtained in CTA and the initial DSA. Conclusions: Digital subtraction angiography must still be considered as the gold standard in the diagnosis of cerebral aneurysms. On account of its excellent spatial delineation of aneurysms and possibilities for exact measurements, CT-angiography represents a valuable, supplementary method - in some cases also an alternative method - to digital subtraction angiography. (orig.) [de

  3. Follow-Up Testing

    Science.gov (United States)

    ... second should occur after 1 year on the gluten-free diet. After that, a celiac should receive follow-up ... test result is straightforward—a celiac on the gluten-free diet should have a negative test. The numerical value ...

  4. Bone marrow edema pattern identification in patients with lytic bone lesions using digital subtraction angiography-like bone subtraction on large-area detector computed tomography.

    Science.gov (United States)

    Gondim Teixeira, Pedro Augusto; Hossu, Gabriela; Lecocq, Sophie; Razeto, Marco; Louis, Matthias; Blum, Alain

    2014-03-01

    The objective of this study was to evaluate the performance of digital subtraction angiography (DSA)-like bone subtraction with 2 different registration methods for the identification of bone marrow edema pattern (BMEP) in patients with lytic bone lesions, using magnetic resonance imaging as the criterion standard. Fifty-five patients with a lytic bone lesion were included in this prospective study with approval from the ethics committee. All patients underwent magnetic resonance imaging and low-dose computed tomographic (CT) perfusion after signing an informed consent. Two CT volumes were used for bone subtraction, which was performed with 2 different algorithms (rigid and nonrigid). Enhancement at the nonlytic bone marrow was considered as a sign of BMEP. Two readers evaluated the images blindly. The presence of BMEP on bone-subtracted CT images was evaluated subjectively and quantitatively. Image quality was assessed. Magnetic resonance imaging was used as the criterion standard. Using a rigid registration method, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT with DSA-like bone subtraction BMEP was 77%, 100%, 100%, 68%, and 85%, respectively. The interobserver agreement was good (κ, 0.782). Image quality was better using a nonrigid registration. With this algorithm, artifacts interfered with image interpretation in only 5% of cases. However, there was a noticeable drop in sensitivity and negative predictive value when a nonrigid algorithm was used: 56% and 52%, respectively. The interobserver agreement was average with a nonrigid subtraction algorithm. Computed tomography with DSA-like bone subtraction is sensitive and highly specific for the identification of BMEP associated with lytic bone lesions. Rigid registering should be preferred, but nonrigid algorithms can be used as a second option when artifacts interfere with image interpretation.

  5. Venous digital subtraction angiography of the renal arteries in hypertensive patients

    International Nuclear Information System (INIS)

    Brecht, G.; Harder, T.; Franken, T.

    1984-01-01

    We carried out 1890 venous digital subtraction angiograms; this included 113 patients with hypertension in order to exclude renal artery stenosis. On four occasions it was used following surgery on a renal artery. Renal artery stenosis or occlusion was demonstrated in twelve patients, and other vascular diseases or anomalies were found in 24. Two abnormal renal arteries were found following renal artery surgery. The results are compared with smaller groups of patients examined by DSA, and with the results of conventional subtraction methods reported in the literature. In only eight patients (6.8%) DSA provided insufficient information and had to be supplemented by aortography. The method has proved to be a valuable and simple screening method for the investigation of hypertension. (orig.) [de

  6. Quantitation of left ventricular dimensions and function by digital video subtraction angiography

    International Nuclear Information System (INIS)

    Higgins, C.B.; Norris, S.L.; Gerber, K.H.; Slutsky, R.A.; Ashburn, W.L.; Baily, N.

    1982-01-01

    Digital video subtraction angiography (DVSA) after central intravenous administration of contrast media was used in experimental animals and in patients with suspected coronary artery disease to quantitate left ventricular dimensions and regional and global contractile function. In animals, measurements of left ventricular (LV) volumes, wall thickness, ejection fraction, segmental contraction, and cardiac output correlated closely with sonocardiometry or thermodilution measurements. In patients, volumes and ejection fractions calculated from mask mode digital images correlated closely with direct left ventriculography. Global and segmental contractile function was displayed in patients by ejection shell images, stroke volume images, and time interval difference images. Central cardiovascular function was also quantitated by measurement of pulmonary transit time and calculation of pulmonary blood volume from digital fluoroscopic images. DVSA was shown to be useful and accurate in the quantitation of central cardiovascular physiology

  7. Accuracy of digital subtraction radiography in combination with a contrast media in assessment of proximal caries depth

    Directory of Open Access Journals (Sweden)

    Farzad Esmaeili

    2008-07-01

    Full Text Available Background and aims. Radiography is used to diagnose the demineralization process and carious lesions; however, conventional radiography and direct digital images do not show these lesions when the amount of demineralization is less than 40%. Digital subtraction radiography has recently been used to improve the diagnostic quality of these lesions. The purpose of this study was to compare the caries depth estimated by digital subtraction radiography in combination with barium sulfate in diagnosing proximal dental caries with histopathologic evaluation. Materials and methods. In this study 30 molars and premolars (24 demineralized lesions with cavity, 8 without cavity were studied. Direct digital images were taken (kVp: 68, mA: 8; t: 0.12 for premolars and t: 0.16 for molars whereas the position of X-ray tube and CCD receptor and teeth was fixed. To prepare the second images 135 gr/L barium sulfate was used. The images obtained with the same exposure and geometry and then subtracted. The depth of the lesions in direct digital and subtracted images were assessed and compared with the depth measured in histopathologic assessments. Results. The mean depths (± SD of the lesions were 1.80 ± 0.77 mm in direct digital radiography, 2.32 ± 0.76 mm in subtracted images after barium sulfate treatment, and 2.51 ± 0.43 mm in histopathologic sections. The statistical difference between direct digital radiography and the other methods was significant (P < 0.05. However, the differences were not statistically significant between subtracted images and histopathologic sections. The average intra-class correlation coefficient was 0.7241 (CI: 95%. Conclusion. The present study has demonstrated that digital subtraction radiography images have the potential to measure the depth of proximal caries with no significant difference with histopathologic evaluation.

  8. CONTRACT FOLLOW UP TRAINING

    CERN Multimedia

    Technical Training; Tel. 74460

    2001-01-01

    SPL is organizing Training Sessions on the Contract Follow Up application. CFU is a Web based tool, developped and supported by the Administrative Information Services. It allows the creation of Divisional Requests and the follow up of their processing, from the Market Survey to the Invitation to Tender or Price Enquiry, approval by the Finance Committee, up to the actual signature of a Contract, acccording to the CERN Purchasing procedures. It includes a document management component. It also provides link with other AIS applications such as BHT and EDH. The course is primarily intended for DPOs, Contract Technical responsibles in the division and their assistants, but is beneficial to anybody involved in the follow up of such Purchasing Procedures. This course is free of charge, but application is necessary. The details of the course may be found at http://training.web.cern.ch/Training/ENSTEC/P2001/Bureautique/cfu4_f.htm General information of CFU may be found at http://ais.cern.ch/apps/cfu/ The dates of t...

  9. The potential for neurovascular intravenous angiography using K-edge digital subtraction angiography

    International Nuclear Information System (INIS)

    Schueltke, E.; Fiedler, S.; Kelly, M.; Griebel, R.; Juurlink, B.; LeDuc, G.; Esteve, F.; Le Bas, J.-F.; Renier, M.; Nemoz, C.; Meguro, K.

    2005-01-01

    Background: Catheterization of small-caliber blood vessels in the central nervous system can be extremely challenging. Alternatively, intravenous (i.v.) administration of contrast agent is minimally invasive and therefore carries a much lower risk for the patient. With conventional X-ray equipment, volumes of contrast agent that could be safely administered to the patient do not allow acquisition of high-quality images after i.v. injection, because the contrast bolus is extremely diluted by passage through the heart. However, synchrotron-based digital K-edge subtraction angiography does allow acquisition of high-quality images after i.v. administration of relatively small doses of contrast agent. Materials and methods: Eight adult male New Zealand rabbits were used for our experiments. Animals were submitted to both angiography with conventional X-ray equipment and synchrotron-based digital subtraction angiography. Results: With conventional X-ray equipment, no contrast was seen in either cerebral or spinal blood vessels after i.v. injection of iodinated contrast agent. However, using K-edge digital subtraction angiography, as little as 1 ml iodinated contrast agent, when administered as i.v. bolus, yielded images of small-caliber blood vessels in the central nervous system (both brain and spinal cord). Conclusions: If it would be possible to image blood vessels of the same diameter in the central nervous system of human patients, the synchrotron-based technique could yield high-quality images at a significantly lower risk for the patient than conventional X-ray imaging. Images could be acquired where catheterization of feeding blood vessels has proven impossible

  10. Assessment of maximal myocardial perfusion by ECG-triggered digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Pijls, N.H.J.; Uijen, G.J.H.; Werf, T. van der (Katholieke Univ. Nijmegen (Netherlands). Cardiology Dept.)

    1991-01-01

    Early studies about calculation of coronary blood flow by analysis of contrast agent passage on the coronary arteriogram were reported more than 2 decades ago by Rutishauser et al. and Smith et al. Thereafter is was shown that visualization of contrast passage through the myocardium could be enhanced by ECG-triggered digital subtraction imaging and it was suggested that myocardial flow could be calculated by studying the temporal changes in contrast intensity in a myocardial region of interest (ROI) as a function of time: the time density curve (TDC). (orig./GDG).

  11. Anatomic and functional imaging of congenital heart disease with digital subtraction angiography

    International Nuclear Information System (INIS)

    Buonocore, E.; Pavlicek, W.; Modic, M.T.; Meaney, T.F.; O'Donovan, P.B.; Grossman, L.B.; Moodie, D.S.; Yiannikas, J.

    1983-01-01

    Digital subtraction angiography (DSA) of the heart was performed in 54 patients for the evaluation of congenital heart diagnostic images and accurate physiologic shunt data that compared favorably with catheter angiography and nuclear medicine studies. Retrospective analysis of this series of patients indicated that DSA studies contributed sufficient informantion to shorten significantly or modify cardiac catheterization in 85% (79/93) of the defects that were identified. Interatrial septal defects were particularly well diagnosed, with identification occurring in 10 of 10 cases, wheseas intraventricular septal defects were identified in only 6 of 9 patients. Evaluation of postsurgical patients was accurate in 19 of 20 cases

  12. Mycotic aneurysms in intravenous drug abusers: the utility of intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Shetty, P.C.; Krasicky, G.A.; Sharma, R.P.; Vemuri, B.R.; Burke, M.M.

    1985-01-01

    Two-hundred thirteen intravenous digital subtraction angiographic (DSA) examinations were performed on 195 intravenous drug abusers to rule out the possibility of a mycotic aneurysm in a groin, neck, or upper extremity infection. Twenty-three surgically proved cases of mycotic aneurysm were correctly identified with no false positive results. In addition, six cases of major venous occlusion were documented. The authors present the results of their experience and conclude that DSA is an effective and cost-efficient method of examining this high risk patient population

  13. Equilibrium radionuclide ventriculography: Comparison with echo-ventriculography and digital subtraction angiocardiography, evaluation of multiparameters

    Energy Technology Data Exchange (ETDEWEB)

    Hoer, G; Standke, R; Klepzig, H Jr; Maul, F D; Tuengerthal, S; Tezak, S; Reifarth, N; Kanemoto, N; Happ, J; Baum, R P

    1986-09-01

    Subsequent to the discussion of technical prerequisites (fully-automated, reproducible multiparameter-analysis (MPA), rest, exercise) which is followed by remarks concerning the pathophysiology of ischemic left ventricular functional disorders in diastole and systole, the following points are considered: 1) comparative results of RNV, cineventriculoangiography, echo-ventriculography and intraveneous digital subtraction angiocardiography; 2) 'normal' values of RNV in MPA; 3) heart and pulmonary diseases (coronary artery disease with sensitivity and specificity of MPA), chronic obstructive pulmonary disease, chronic aortic insufficiency, hypertension; 4) summary of, and prospects for future potentialities (software, clinical indications).

  14. Visualisation of bony and vascular structures via digital subtraction images upon the amount of anatomic background

    International Nuclear Information System (INIS)

    Hinz, A.; Scholz, A.; Zwicker, C.

    1992-01-01

    We examined the loss of contrast leaving a part of the anatomic background in digital subtraction angiography by visual analysis and densitometry. We observed a greater loss of the quality at the representation of the bone below than above an amount of anatomic background of 60%. The loss of quality at the representation of the vessels decreases more above than below an anatomical background of 45%. We think that, depending on the clinical problem, an anatomical background between 15 and 30% should be left. (orig.) [de

  15. Pelvic digital subtraction catheter angiography-Are routine oblique projections necessary?

    International Nuclear Information System (INIS)

    Rane, Neil; Imam, Atique; Foley, Peter; Timmons, Grace; Uberoi, Raman

    2011-01-01

    The oblique projection is used widely in imaging of the lower vascular tree. Much of the evidence justifying the oblique projection is anecdotal. This study compares the sensitivity of the anteroposterior (AP) projection alone in lower limb vascular catheter angiography to that combined with the oblique projection. 110 digitally subtracted angiograms were analysed initially on AP and subsequently on oblique views. Oblique imaging increases confidence, demonstrates stenoses not seen on AP and changes the diagnosis. This supports the use of the oblique projection in lower limb vascular interventional imaging.

  16. Advantages and limitation of intra-arterial digital subtraction angiography (i.a. DSA)

    International Nuclear Information System (INIS)

    Beduhn, D.

    1986-01-01

    Among 3000 digital subtraction angiographies which have been performed in our institute, 850 patients have been examined intraarterially. The advantage of i.a. DSA is due to the excellent demonstration of vessels in survey angiograms by small amounts of contrast medium (10-20 ml in the aorta), without risk of selective catheterisation into the neck vessels, the saving of expensive film series, the short duration of vessel examinations and the small complication rate. i.a. DSA can be carried out on outpatients also, using the 4/5 F-catheter, which saves hospital charges. Impressive examples show the advantages of i.a. DSA. (orig.) [de

  17. Demonstration of an optoelectronic interconnect architecture for a parallel modified signed-digit adder and subtracter

    Science.gov (United States)

    Sun, Degui; Wang, Na-Xin; He, Li-Ming; Weng, Zhao-Heng; Wang, Daheng; Chen, Ray T.

    1996-06-01

    A space-position-logic-encoding scheme is proposed and demonstrated. This encoding scheme not only makes the best use of the convenience of binary logic operation, but is also suitable for the trinary property of modified signed- digit (MSD) numbers. Based on the space-position-logic-encoding scheme, a fully parallel modified signed-digit adder and subtractor is built using optoelectronic switch technologies in conjunction with fiber-multistage 3D optoelectronic interconnects. Thus an effective combination of a parallel algorithm and a parallel architecture is implemented. In addition, the performance of the optoelectronic switches used in this system is experimentally studied and verified. Both the 3-bit experimental model and the experimental results of a parallel addition and a parallel subtraction are provided and discussed. Finally, the speed ratio between the MSD adder and binary adders is discussed and the advantage of the MSD in operating speed is demonstrated.

  18. Intraarterial digital subtraction angiography after coronary bypass surgery - an alternative to coronary angiography

    International Nuclear Information System (INIS)

    Hauenstein, H.K.; Roeren, T.; Schlosser, V.; Urbani, B.

    1985-01-01

    Intraarterial digital subtraction angiography after coronary bypass surgery - an alternative to coronary angiography. Intraarterial DSA is a suitable method for early postoperative control of coronary artery bypass grafts. Small quantities of contrast media with low iodine content are injected into the aortic root. Investigations can be carried out with a routine fluoroscopic and digital equipment; additional cine-technique and analogue memory disc are not necessary. At an image rate of 3/s the bypass anastomoses can be exactly visualized in 75%, whereas diagnostic information was not sufficient in only 4% of all cases. The use of modern F-5-catheters and the nonselective injection make this method a less invasive alternative to coronary angiography. It is paticularly useful in evaluation of short- and long-term results. (orig.) [de

  19. Comparison of the diagnostic accuracy of direct digital radiography system, filtered images, and subtraction radiography

    Directory of Open Access Journals (Sweden)

    Wilton Mitsunari Takeshita

    2013-01-01

    Full Text Available Background: To compare the diagnostic accuracy of three different imaging systems: Direct digital radiography system (DDR-CMOS, four types of filtered images, and a priori and a posteriori registration of digital subtraction radiography (DSR in the diagnosis of proximal defects. Materials and Methods: The teeth were arranged in pairs in 10 blocks of vinyl polysiloxane, and proximal defects were performed with drills of 0.25, 0.5, and 1 mm diameter. Kodak RVG 6100 sensor was used to capture the images. A posteriori DSR registrations were done with Regeemy 0.2.43 and subtraction with Image Tool 3.0. Filtered images were obtained with Kodak Dental Imaging 6.1 software. Images (n = 360 were evaluated by three raters, all experts in dental radiology. Results: Sensitivity and specificity of the area under the receiver operator characteristic (ROC curve (Az were higher for DSR images with all three drills (Az = 0.896, 0.979, and 1.000 for drills 0.25, 0.5, and 1 mm, respectively. The highest values were found for 1-mm drills and the lowest for 0.25-mm drills, with negative filter having the lowest values of all (Az = 0.631. Conclusion: The best method of diagnosis was by using a DSR. The negative filter obtained the worst results. Larger drills showed the highest sensitivity and specificity values of the area under the ROC curve.

  20. Videodensitometric assessment of right and left ventricular functions by digital subtraction angiography

    International Nuclear Information System (INIS)

    Ikeda, Hisao; Yoshiga, Osamu; Shibao, Keigo

    1987-01-01

    Intravenous digital subtraction (DS) ventriculography was performed in a series of 50 patients with heart diseases to determine right and left ventricular volumes and systolic indices. Right ventricular volume and right ventricular ejection fraction obtained by DS ventriculography were well correlated with those by geometric methods. In 43 patients with left ventricular ejection fraction of 55 % or greater, end-diastolic volume, stroke volume, and ejection fraction in the right ventricle did not differ from those in the left ventricle ; however, both the 1/3 ejection fraction and the peak ejection rate of the right ventricle were significantly lower than those of the left ventricle, suggesting the different modes of left and right ventricular contraction. In the other seven patients with chronic left ventricular failure, right ventricular systolic function may be preserved, even when left ventricular function is severely impaired. Digital subtraction ventriculography has proved to be a simple, useful method in the quanlitative and quantitative assessments of the right and left ventricles. (Namekawa, K.)

  1. Quantitative assessment of angiographic perfusion reduction using color-coded digital subtraction angiography during transarterial chemoembolization.

    Science.gov (United States)

    Wang, Ji; Cheng, Jie-Jun; Huang, Kai-Yi; Zhuang, Zhi-Guo; Zhang, Xue-Bin; Chi, Jia-Chang; Hua, Xiao-Lan; Xu, Jian-Rong

    2016-03-01

    The aim of this study was to develop a quantitative measurement of perfusion reduction using color-coded digital subtraction angiography (ccDSA) to monitor intra-procedural arterial stasis during TACE. A total number of 35 patients with hepatocellular carcinoma who had undergone TACE were enrolled into the study. Pre- and post-two-dimensional digital subtraction angiography scans were conducted with same protocol and post-processed with ccDSA prototype software. Time-contrast-intensity (CI[t]) curve was obtained by region-of-interest (ROI) measurement on the generated ccDSA image. Quantitative 2D perfusion parameters time to peak, area under the curve (AUC), maximum upslope, and contrast intensity peak (CI-Peak) derived from the ROI-based CI[t] curve for pre- and post-TACE were evaluated to assess the reduction of antegrade blood flow and tumor blush. Relationships between 2D perfusion parameters, subjective angiographic chemoembolization endpoint (SACE) scale, and clinical outcomes were analyzed. Area normalized AUC and CI-Peak revealed significant reduction after the TACE (P SACE level III and a reduction ranging from 60% to 70% was equivalent to SACE level IV. For intermediate reduction (SACE level III), better tumor response was found after TACE rather than a higher reduction (SACE level IV). ccDSA application provides an objective approach to quantify the perfusion reduction and subjectively evaluate the arterial stasis of antegrade blood flow and tumor blush caused by TACE.

  2. Analytical optimization of digital subtraction mammography with contrast medium using a commercial unit.

    Science.gov (United States)

    Rosado-Méndez, I; Palma, B A; Brandan, M E

    2008-12-01

    Contrast-medium-enhanced digital mammography (CEDM) is an image subtraction technique which might help unmasking lesions embedded in very dense breasts. Previous works have stated the feasibility of CEDM and the imperative need of radiological optimization. This work presents an extension of a former analytical formalism to predict contrast-to-noise ratio (CNR) in subtracted mammograms. The goal is to optimize radiological parameters available in a clinical mammographic unit (x-ray tube anode/filter combination, voltage, and loading) by maximizing CNR and minimizing total mean glandular dose (D(gT)), simulating the experimental application of an iodine-based contrast medium and the image subtraction under dual-energy nontemporal, and single- or dual-energy temporal modalities. Total breast-entrance air kerma is limited to a fixed 8.76 mGy (1 R, similar to screening studies). Mathematical expressions obtained from the formalism are evaluated using computed mammographic x-ray spectra attenuated by an adipose/glandular breast containing an elongated structure filled with an iodinated solution in various concentrations. A systematic study of contrast, its associated variance, and CNR for different spectral combinations is performed, concluding in the proposal of optimum x-ray spectra. The linearity between contrast in subtracted images and iodine mass thickness is proven, including the determination of iodine visualization limits based on Rose's detection criterion. Finally, total breast-entrance air kerma is distributed between both images in various proportions in order to maximize the figure of merit CNR2/D(gT). Predicted results indicate the advantage of temporal subtraction (either single- or dual-energy modalities) with optimum parameters corresponding to high-voltage, strongly hardened Rh/Rh spectra. For temporal techniques, CNR was found to depend mostly on the energy of the iodinated image, and thus reduction in D(gT) could be achieved if the spectral energy

  3. The reduction of motion artifacts in digital subtraction angiography by geometrical image transformation

    International Nuclear Information System (INIS)

    Fitzpatrick, J.M.; Pickens, D.R.; Mandava, V.R.; Grefenstette, J.J.

    1988-01-01

    In the diagnosis of arteriosclerosis, radio-opaque dye is injected into the interior of the arteries to make them visible. Because of its increased contrast sensitivity, digital subtraction angiography has the potential for providing diagnostic images of arteries with reduced dye volumes. In the conventional technique, a mask image, acquired before the introduction of the dye, is subtracted from the contrast image, acquired after the dye is introduced, to produce a difference image in which only the dye in the arteries is visible. The usefulness of this technique has been severely limited by the image degradation caused by patient motion during image acquisition. This motion produces artifacts in the difference image that obscure the arteries. One technique for dealing with the problem is to reduce the degradation by means of image registration. The registration is carried out by means of a geometrical transformation of the mask image before subtraction so that it is in registration with the contrast image. This paper describes a technique for determining an optimal transformation. The authors employ a one-to-one elastic mapping and the Jacobian of that mapping to produce a geometrical image transformation. They choose a parameterized class of such mappings and use a heuristic search algorithm to optimize the parameters to minimize the severity of the motion artifacts. To increase the speed of the optimization process they use a statistical image comparison technique that provides a quick approximate evaluation of each image transformation. They present the experimental results of the application of their registration system to mask-contrast pairs, for images acquired from a specially designed phantom, and for clinical images

  4. Assessment of blood supply to intracranial pathologies in children using MR digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Chooi, Weng Kong; Coley, Stuart C. [Royal Hallamshire Hospital, Department of Radiology, Sheffield (United Kingdom); Connolly, Dan J.A. [Royal Hallamshire Hospital, Department of Radiology, Sheffield (United Kingdom); Sheffield Children' s Hospital, Department of Radiology, Sheffield (United Kingdom); Griffiths, Paul D. [Royal Hallamshire Hospital, Department of Radiology, Sheffield (United Kingdom); Sheffield Children' s Hospital, Department of Radiology, Sheffield (United Kingdom); University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Floor C, Royal Hallamshire Hospital, Section of Academic Radiology, Sheffield (United Kingdom)

    2006-10-15

    MR digital subtraction angiography (MR-DSA) is a contrast-enhanced MR angiographic sequence that enables time-resolved evaluation of the cerebral circulation. We describe the feasibility and technical success of our attempts at MR-DSA for the assessment of intracranial pathology in children. We performed MR-DSA in 15 children (age range 5 days to 16 years) referred for MR imaging because of known or suspected intracranial pathology that required a dynamic assessment of the cerebral vasculature. MR-DSA consisted of a thick (6-10 mm) slice-selective RF-spoiled fast gradient-echo sequence (RF-FAST) acquired before and during passage of an intravenously administered bolus of Gd-DTPA. The images were subtracted and viewed as a cine loop. MR-DSA was performed successfully in all patients. High-flow lesions were shown in four patients; these included vein of Galen aneurysmal malformation, dural fistula, and two partially treated arteriovenous malformations (AVMs). Low-flow lesions were seen in three patients, all of which were tumours. Normal flow was confirmed in eight patients including two with successfully treated AVMs, and in three patients with cavernomas. Our early experience suggests that MR-DSA is a realistic, non-invasive alternative to catheter angiography in certain clinical settings. (orig.)

  5. Assessment of blood supply to intracranial pathologies in children using MR digital subtraction angiography

    International Nuclear Information System (INIS)

    Chooi, Weng Kong; Coley, Stuart C.; Connolly, Dan J.A.; Griffiths, Paul D.

    2006-01-01

    MR digital subtraction angiography (MR-DSA) is a contrast-enhanced MR angiographic sequence that enables time-resolved evaluation of the cerebral circulation. We describe the feasibility and technical success of our attempts at MR-DSA for the assessment of intracranial pathology in children. We performed MR-DSA in 15 children (age range 5 days to 16 years) referred for MR imaging because of known or suspected intracranial pathology that required a dynamic assessment of the cerebral vasculature. MR-DSA consisted of a thick (6-10 mm) slice-selective RF-spoiled fast gradient-echo sequence (RF-FAST) acquired before and during passage of an intravenously administered bolus of Gd-DTPA. The images were subtracted and viewed as a cine loop. MR-DSA was performed successfully in all patients. High-flow lesions were shown in four patients; these included vein of Galen aneurysmal malformation, dural fistula, and two partially treated arteriovenous malformations (AVMs). Low-flow lesions were seen in three patients, all of which were tumours. Normal flow was confirmed in eight patients including two with successfully treated AVMs, and in three patients with cavernomas. Our early experience suggests that MR-DSA is a realistic, non-invasive alternative to catheter angiography in certain clinical settings. (orig.)

  6. Assessment of blood supply to intracranial pathologies in children using MR digital subtraction angiography.

    Science.gov (United States)

    Chooi, Weng Kong; Connolly, Dan J A; Coley, Stuart C; Griffiths, Paul D

    2006-10-01

    MR digital subtraction angiography (MR-DSA) is a contrast-enhanced MR angiographic sequence that enables time-resolved evaluation of the cerebral circulation. We describe the feasibility and technical success of our attempts at MR-DSA for the assessment of intracranial pathology in children. We performed MR-DSA in 15 children (age range 5 days to 16 years) referred for MR imaging because of known or suspected intracranial pathology that required a dynamic assessment of the cerebral vasculature. MR-DSA consisted of a thick (6-10 mm) slice-selective RF-spoiled fast gradient-echo sequence (RF-FAST) acquired before and during passage of an intravenously administered bolus of Gd-DTPA. The images were subtracted and viewed as a cine loop. MR-DSA was performed successfully in all patients. High-flow lesions were shown in four patients; these included vein of Galen aneurysmal malformation, dural fistula, and two partially treated arteriovenous malformations (AVMs). Low-flow lesions were seen in three patients, all of which were tumours. Normal flow was confirmed in eight patients including two with successfully treated AVMs, and in three patients with cavernomas. Our early experience suggests that MR-DSA is a realistic, non-invasive alternative to catheter angiography in certain clinical settings.

  7. Intra-arterial digital subtraction angiography (IA-DSA) with carbon dioxide

    International Nuclear Information System (INIS)

    Takeda, Toshiaki; Ido, Kunio; Yuasa, Yuji

    1988-01-01

    Intra-Arterial Digital Subtraction Angiography (IA-DSA) with Carbon Dioxide (CO 2 ) was performed on 41 patients mainly with liver or renal diseases, and its angiographic manifestation was compared with that of conventional angiography. Although the image quality of the arterial or capillary phase was inferior to that of conventional angiography with iodinated contrast media, the detectablity of arterio-venous shunting was excellent. In fact, DSA with CO 2 revealed the presence of A-V (A-P) shunt in 26 patients (26/41:63.4 % HCC, 13/15:86.7% metastatic liver tumor, 2/3:66.7 % RCC, 1/5:20 %). On the other hand, conventional angiography was able to show in only 5 cases. DSA with CO 2 will become an effective method for detecting minute arterio-venous shunting which can not be demonstrated with conventional angiography. (author)

  8. Intraarterial digital subtraction angiography of peripheral arteries with isotonic contrast material

    International Nuclear Information System (INIS)

    Yashiro, Naobumi; Itai, Yuji; Ohtomo, Kuni; Furui, Shigeru; Iio, Masahiro

    1984-01-01

    Intraarterial digital subtraction angiography (IADSA) of peripheral arteries with isotonic contrast material, which was prepared by diluting meglumine amidotrizoate (65% Angiografin), was performed in ten patients. In six, both IADSA and conventional screen-film arteriography were performed for comparison. Painless peripheral arteriography was achieved by IADSA with isotonic contrast material. Five IADSAs were safely done on an outpatient basis. Visualization of arteries by IADSA was satisfactory, but the details of smaller arteries were better shown by screen-film arteriography. Visualization of faint stains was better in IADSA. The authors believe that IADSA with isotonic contrast material is a method of choice for the diagnosis of vascular diseases and tumorous conditions of extremities, as well as for the purpose of preoperative vascular mapping. It is safely performed with smaller dose of contrast material on outpatient basis, and with less discomfort and cost for the patient. (author)

  9. [Affine transformation-based automatic registration for peripheral digital subtraction angiography (DSA)].

    Science.gov (United States)

    Kong, Gang; Dai, Dao-Qing; Zou, Lu-Min

    2008-07-01

    In order to remove the artifacts of peripheral digital subtraction angiography (DSA), an affine transformation-based automatic image registration algorithm is introduced here. The whole process is described as follows: First, rectangle feature templates are constructed with their centers of the extracted Harris corners in the mask, and motion vectors of the central feature points are estimated using template matching technology with the similarity measure of maximum histogram energy. And then the optimal parameters of the affine transformation are calculated with the matrix singular value decomposition (SVD) method. Finally, bilinear intensity interpolation is taken to the mask according to the specific affine transformation. More than 30 peripheral DSA registrations are performed with the presented algorithm, and as the result, moving artifacts of the images are removed with sub-pixel precision, and the time consumption is less enough to satisfy the clinical requirements. Experimental results show the efficiency and robustness of the algorithm.

  10. Somatic and genetic radiation exposure of the patient in digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Neufang, K.F.R.; Ewen, K.

    1986-01-01

    The somatic and genetic radiation exposure of patients undergoing Digital Subtraction Angiography (DSA) and traditional Film Arteriography (FA) of cranial, cervical, thoracic and abdominal vascular territories are compared. The radiation doses absorbed within the critical organs - red bone marrow, lung, thyroid gland and female breast - and in the gonads were measured using an anthropomorphic Alderson phantom. A Somatic Dose Index was calculated in order to estimate the somatic radiation risk. The somatic radiation exposure depends upon the location of the critical organs with respect to the entrance site of the x-ray beam, and can be reduced by an appropriate choice of the angiographic projection. Under this condition, the radiation exposure of the patient during DSA can be lower than during FA. For renal DSA an a.p. projection, the use of an abdominal compression device and careful caudal shielding of the field are advocated. (orig.)

  11. Selective intra-arterial digital subtraction angiography (IADSA) in cerebrovascular disease

    International Nuclear Information System (INIS)

    Uchino, Akira; Satoh, Yoshiyuki; Ohno, Masato

    1987-01-01

    Selective right transbrachial intra-arterial digital subtraction angiography (transbrachial selective IADSA) was successfully performed for 24 of 26 patients with known or suspected cerebrovascular disease, four of whom were outpatients. Catheterization failed in two elderly hypertensive men because of tortuosity of their brachial arteries, and in one woman whose aberrant right subclavian artery (SCA) prevented bilateral common carotid arterial (CCA) catheterizations. No complications occurred. One-hundred and ten ''excellent'' images were obtained by means of 118 injections for the 24 patients. Iopamidol, the contrast medium, was diluted to 50 % concentration with saline, then warmed to 37 deg C. Nearly all the injections of both CCAs and right vertebral arteries (VAs) were completed using 10 ml injections and a 5 ml/sec flow rate. The mean examination time for the three-vessel study was 29.4 minutes. Transbrachial selective IADSA thus proved to be a safe, useful, and relatively easy means of diagnosing cerebrovascular disease. (author)

  12. The use of neurovascular ultrasound versus digital subtraction angiography in acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Marcos C. Lange

    2015-03-01

    Full Text Available Cervical and intracranial arterial evaluation is an important issue for acute ischemic stroke (IS. Objective Compare the use of the neurovascular ultrasound examination (NVUE to digital subtraction angiography (DSA in acute IS patients for diagnosing significant extracranial and intracranial arteriopathy. Method Nonconsecutive patients with IS or transient ischemic attack admitted within 12 hours of the onset of symptoms were evaluated retrospectively. Standardized NVUE and DSA were done in all patients within the first 120 hours of hospital admission. Results Twenty-four patients were included in the study. Compared to DSA, the NVUE demonstrated 94.7% sensitivity and 100% specificity for identifying symptomatic extracranial and/or intracranial arteriopathy. Conclusion The standardized NVUE technique demonstrated high sensitivity and specificity compared to DSA for diagnosing arterial abnormalities in acute IS patients.

  13. Digital subtraction angiography of lower limb arteries using and automatic table translation. Feasibility. Preliminary results

    International Nuclear Information System (INIS)

    Seka, R.; Amiel, M.; Boller, A.; Chapelon, C.; Clermont, A.; Revel, D.; Pinet, F.

    1988-01-01

    Digital subtraction angiography (DSA) as a method of evaluating lower limb arteries required examination of one limb at a time up to now. Moreover repeated injections of contrast material were necessary. This problem was mainly due to the relative small image intensifier field available and to the difficulty of repositionning the patient between mask and image acquisition. The preliminary results obtained with 24 patients studied on angiographic unit equipped with: a DSA system (DG 300-CGR) using 512x512 matrix size, an angiographic table (Angix M 200) allowing an automatic sequantial translation, a removable image intensifier using a 16 inch field below the table, are reported. Thus, all those characteristics allow DSA of lower limb arteries. Only one injection of contrast material (Ioxaglate: 80 ml at 8-10 ml/second) was used per procedure. This, usually, allows good quality examination of lower limb arteries [fr

  14. Application of a stereoscopic digital subtraction angiography approach to blood flow analysis

    International Nuclear Information System (INIS)

    Fencil, L.E.; Doi, K.; Hoffmann, K.R.

    1986-01-01

    The authors are developing a stereoscopic digital subtraction angiographic (DSA) approach for accurate measurement of the size, magnification factor, orientation, and blood flow of a selected vessel segment. We employ a Siemens Digitron 2 and a Stereolix x-ray tube with a 25-mm tube shift. Absolute vessel sizes in each stereoscopic image are determined using the magnification factor and an iterative deconvolution technique employing the LSF of the DSA system. From data on vessel diameter and three-dimensional orientation, the effective attenuation coefficient of the diluted contrast medium can be determined, thus allowing accurate blood flow analysis in high-frame-rate DSA images. The accuracy and precision of the approach will be studied using both static and dynamic phantoms

  15. Parametric Imaging Of Digital Subtraction Angiography Studies For Renal Transplant Evaluation

    Science.gov (United States)

    Gallagher, Joe H.; Meaney, Thomas F.; Flechner, Stuart M.; Novick, Andrew C.; Buonocore, Edward

    1981-11-01

    A noninvasive method for diagnosing acute tubular necrosis and rejection would be an important tool for the management of renal transplant patients. From a sequence of digital subtraction angiographic images acquired after an intravenous injection of radiographic contrast material, the parametric images of the maximum contrast, the time when the maximum contrast is reached, and two times the time at which one half of the maximum contrast is reached are computed. The parametric images of the time when the maximum is reached clearly distinguish normal from abnormal renal function. However, it is the parametric image of two times the time when one half of the maximum is reached which provides some assistance in differentiating acute tubular necrosis from rejection.

  16. Spectrum of results of arterial digital subtraction angiography in patients after renal transplantation

    International Nuclear Information System (INIS)

    Gruetzner, G.; Bach, D.; Fluer, P.; Kniemeyer, H.W.; Moedder, U.

    1994-01-01

    Digital subtraction angiography (DSA) was performed in 53 of 417 patients with renal transplants. The incidence of clinical apparent vascular complications was 9.1% of all patients with renal transplants (38/417). The most frequent vascular disorders were formed by arterial stenoses at 5.0% of the cases followed by arterial obstructions in 1.7% of the patients. Rare vascular complications were arteriovenous fistulas (0.7%), aneurysms (0.5%) and venous thrombose (0.2%). Because of the high diagnostic value of intraarterial DSA, all patients with renal transplants with a complicated postoperative course should be eligible for angiographic control. In case of a suspected vascular disorder intraarterial DSA should be performed at an early stage. (orig.)

  17. Combined use of intraarterial digital subtraction angiography with conventional retrograde brachial vertebral angiography

    International Nuclear Information System (INIS)

    Yamaguchi, Tatsuo; Ogawa, Toshihide; Inugami, Atsushi; Kawata, Yasushi; Shishido, Fumio; Uemura, Kazuo

    1985-01-01

    For 102 patients who had the examination of conventional bilaterally retrograde brachial vertebral angiography (retrograde VAG), intraarterial digital subtraction angiography (DSA) was successively performed to investigate steno-occlusive lesions of proximal vertebral and subclavian arteries. All the patients had no complication due to the DSA procedure. In 50% of 72 ischemic stroke cases, positive findings were found either in the origin of the vertebral artery or in the subclavian artery. Stenosis of more than 50% of the lumen of the vertebral artery were found in 14% of the cases at the origin of the right one and also in 14% in the left one. Occlusion of the vertebral artery was found in 4% in the left side only. In 30 cases with non-ischemic brain diseases, positive findings were noted in 10%. Intraarterial DSA combined with retrograde VAG was thought to be useful, especially in the examination for ischemic stroke. (author)

  18. Intraarterial digital subtraction angiography after plastic surgery by thin-needle puncture

    International Nuclear Information System (INIS)

    Langer, M.; Fiegler, W.; Claussen, C.; Koehler, D.; Felix, R.; Hepp, W.

    1984-01-01

    Over the period of a year (1983), 44 intraarterial digital subtraction angiographies (DSA) via direct thin-needle puncture of a vascular bypass or following vascular graft were carried the rough. The only complication that occured: paravasal injection, was clinically insignificant and could be avoided by a change in the puncture-technique. It was possible to carry through the investigation in out-patients. In all cases, diagnostically useful picture material for a possible surgical intervention was obtained. The pictures always were high-grade, independently of the patient's circulation time. Because this is a simple investigation and because of the small risk of complications, it has come to be regularly carried through as a routine in the authors' clinic. According to investigations carried through on the collective of patients of a vascular surgery department, occlusions or anastomotic aneurismus account for most of the angiological disorders. (orig.) [de

  19. Indications for intra-arterial digital subtraction angiography (DSA) in vascular disease

    International Nuclear Information System (INIS)

    Neufang, K.F.R.; Friedmann, G.; Peters, P.E.; Moedder, U.

    1983-01-01

    Digital subtraction angiography (DSA), using a direct arterial route, diminishes the risk of the examination by reducing the contrast dose by about 75%, making the examination more rapid and making it less likely that catheters will have to be changed. At the same time superimposition is avoided, one of the advantages of selective catheterisation. In view of the low contrast dose, it is possible to carry out several examinations at one time and to use additional projections for intracranial and peripheral disease, thereby improving the diagnostic value of the examination. For certain problems, intra-arterial DSA is already able to replace conventional angiography. The small field size and poor spatial resolution still make conventional angiography necessary as the basic form of investigation in most other circumstances. (orig.) [de

  20. Routine evaluation ot arteriopathies of the lower extremities by digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Stacul, F; Pozzi-Mucelli, R; Predonzan, F; Magnaldi, S; Abbona, M; Pozzi-Mucelli, R S; Dalla Palma, L

    1985-11-01

    Intravenous digital subtraction angiography (DSA) was performed in 119 patients with lower extremity ischemia using a 14'' amplifier. Four injections of contrast medium were usually necessary for a complete evaluation of this vascular region. Images of good quality were obtained in most cases; movement artifacts and a faint opacification accounted for any poor results, which occured mainly under the knee. The technique of pixel shifting turned out to be very useful to remove movement artifacts. The 'measuring field' allowed us to minimize the problem of the inhomogeneous saturation of the amplifier. In 8% of the cases an intra-arterial DSA has been performed after an unsatisfactory intravenous examination. Conventional angiography appears to be no longer necessary.

  1. Digital subtraction angiography of inferior gluteal artery through the infusion catheter of chemotherapy for bladder cancer

    International Nuclear Information System (INIS)

    Ishikawa, Satoru; Noguchi, Ryosuke; Kanoh, Shori; Shimazui, Toru; Uchida, Katsunori; Nemoto, Ryosuke; Koiso, Kenkichi

    1987-01-01

    More than fifty patients of invasive bladder cancer had been treated by selective intra-arterial chemotherapy through the inferior or superior gluteal arteries. The distribution of infused drugs had been evaluated by RI-angiography through a thin arterial infusion catheter. This time we performed digital subtraction angiography (DSA) through an infusion catheter in order to know the precise distribution of infused materials in seven patients with locally advanced bladder cancer. Pharmaco-DSA with norepinephrine was also done in four patients. Satisfactory spatial and contrast resolution were gained in four patients and pharmaco-DSA showed better quality. In our experience DSA through intra-arterial infusion catheter was a useful procedure in the evaluation of distribution of infused drugs. (author)

  2. Intravenous digital subtraction angiography of the lower limbs combined with field movement (2-field DSA)

    International Nuclear Information System (INIS)

    Fritschy, P.; Terrier, F.

    1988-01-01

    We evaluated a bolus-chase technique designed to reduce the volume of contrast material and to shorten examination time during intravenous digital subtraction angiography (IV-DSA) of the lower limbs. With this technique, after a single injection of contrast material, two contiguous fields can be sequentially imaged (two-field DAS) using a step translated X-ray tube. 67 patients with peripheral vascular disease were studied. All examinations provided diagnostic information, so that in no instance additional intra-arterial injections were required. With the two-field DSA only 3.49 injections were needed in the average for five fields examined in each patient, resulting in a 30% reduction of contrast agent used. (orig.) [de

  3. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Kocasarac, Husniye Demirturk [Dept. of Comprehensive Dentistry, The University of Texas Health Science Center, San Antonio (United States); Celenk, Peruze [Dept. of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ondokuz Mayis University, Samsun (Turkmenistan)

    2017-06-15

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images.

  4. Analysis of digital subtraction angiography for estimating flow reserve in critical coronary artery stenosis

    International Nuclear Information System (INIS)

    Kotoku, Shinya; Matsuzaki, Masunori; Otani, Nozomi

    1988-01-01

    To assess the accuracy of digital subtraction angiography in evaluating coronary flow reserve in cases with critical coronary artery stenosis, time-density curves were obtained from digital subtraction coronary angiograms in the myocardial region of interest. Time to peak contrast (TPC) and time constant of the washout exponential curve (T) were measured in 14 patients with stable effort angina pectoris and critical one vessel lesion before and after percutaneous transluminal coronary angioplasty (PTCA). All patients had normal left ventricular ejection fraction (59±7%) and 201 Tl myocardial images at rest. The values of TPC and T were significantly shortened from 5.4±1.3 to 4.5±1.0 sec (p<0.02) and from 10.9±3.8 to 5.3±1.3 sec (p<0.001) after PTCA, respectively. However, in 9 patients TPC values were approximately the same before and after PTCA. In five experimental dogs with critical circumflex coronary artery stenosis, coronary flow (CF; Doppler flowmeter) and systolic thickening of the posterior wall (by sonomicrometry) at rest did not differ from those of the controls. However, contrast media-induced reactive hyperemia was markedly attenuated, accompanied by a significant increase in T (7.7±4.5 vs 15.8±10.9 sec, p<0.01) and totally unchanged TPC (both 6.8 sec). With simultaneous tracings of CF and time-density curves, TPC and washout phases corresponded with contrast-induced transient CF reduction and hyperemic phases, respectively. We concluded that T may be more sensitive for estimating CF maintained nearly normal, e.g., in patients with stable effort angina pectoris having normal left ventricular wall motion at rest. (author)

  5. Analysis of digital subtraction coronary angiography for estimation of flow reserve in critical coronary stenosis

    International Nuclear Information System (INIS)

    Kohtoku, Shinya

    1988-01-01

    To examine the accuracy of digital subtraction angiographic assessment of coronary flow reserve in critical coronary stenosis, time-density curve was obtained from digital subtraction coronary angiograms for myocardial region of interest. Time to peak contrast(TPC) and time constant of the washout exponential curve(T) were measured in 14 patients with stable effort angina pectoris and critical one vessel lesion before and after percutaneous transluminal coronary angioplasty(PTCA). All patients had normal left ventricular ejection fraction (59 ± 7 %) and Tl 201 myocardial image at rest. The values of TPC and T were significantly shortened from 5.4 ± 1.3 to 4.5 ± 1.0 sec (p < 0.02) and from 10.9 ± 3.8 to 5.3 ± 1.3 sec(p < 0.001) after PTCA, respectively. However, in 9 of all patients TPC after PTCA showed approximately the same valued as those before PTCA. In 5 experimental dogs with critical circumflex stenosis, coronary flow(CF;Doppler flow meter) and systolic thickning of the posterior wall(by sonomicrometry) at rest were not different from control, however, contrast media-induced reactive hyperemia was markedly attenuated, accompanied with a significant of T (7.7 ± 4.5 vs 15.8 ± 10.9 sec, p < 0.01) and completely unchanged TPC (both 6.8 sec). With simultaneous tracing of CF and time-density curve, TPC and washout phase corresponded with contrast-induced transient CF reduction and hyperemic phase, respectively. We conclude that T might be more sensitive for estimation of CF is maintained almost normal, such as patients with stable effort angina pectoris having normal left ventricular wall motion at rest. (author)

  6. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    International Nuclear Information System (INIS)

    Kocasarac, Husniye Demirturk; Celenk, Peruze

    2017-01-01

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images

  7. Evaluation of chronic periapical lesions by digital subtraction radiography by using Adobe Photoshop CS: a technical report.

    Science.gov (United States)

    Carvalho, Fabiola B; Gonçalves, Marcelo; Tanomaru-Filho, Mário

    2007-04-01

    The purpose of this study was to describe a new technique by using Adobe Photoshop CS (San Jose, CA) image-analysis software to evaluate the radiographic changes of chronic periapical lesions after root canal treatment by digital subtraction radiography. Thirteen upper anterior human teeth with pulp necrosis and radiographic image of chronic periapical lesion were endodontically treated and radiographed 0, 2, 4, and 6 months after root canal treatment by using a film holder. The radiographic films were automatically developed and digitized. The radiographic images taken 0, 2, 4, and 6 months after root canal therapy were submitted to digital subtraction in pairs (0 and 2 months, 2 and 4 months, and 4 and 6 months) choosing "image," "calculation," "subtract," and "new document" tools from Adobe Photoshop CS image-analysis software toolbar. The resulting images showed areas of periapical healing in all cases. According to this methodology, the healing or expansion of periapical lesions can be evaluated by means of digital subtraction radiography by using Adobe Photoshop CS software.

  8. A digital subtraction radiography based tool for periodontal bone resorption analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schiabel, Homero; Rodrigues, Eveline B., E-mail: homero@sc.usp.br [University of Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). Dept. of Electrical Engineering; Rubira-Bullen, Izabel R.F. [University of Sao Paulo (USP), Bauru, SP (Brazil). Bauru Dentistry School

    2011-07-01

    The aim of this paper was to describe an aided diagnosis scheme for periodontal bone resorption so that the dentist can make an early diagnosis of the periodontal disease and establish the best treatment plan to increase the success of healing. Three ways of displaying the results are provided: qualitative, simple quantitative and colored-percentage quantitative views. A total of 72 pairs of in vitro radiographic images were used. The main procedure registers the images perspective projection aimed to align them in rotation and translation, and is followed by the application of a contrast correction technique. The results from the subtraction were evaluated firstly by the comparison between the actual and the digital sizes corresponding to the holes made by drills in phantoms. The mean error was 4.2%. The method was also applied to actual tooth radiographic images and could detect clearly the effect of treatment of periodontal diseases. It is dependent on the reproducibility of the process of radiographs acquisition and digitization, but the calculated mean error allows to conclude its better efficacy compared to usual procedures in this field. (author)

  9. A digital subtraction radiography based tool for periodontal bone resorption analysis

    International Nuclear Information System (INIS)

    Schiabel, Homero; Rodrigues, Eveline B.; Rubira-Bullen, Izabel R.F.

    2011-01-01

    The aim of this paper was to describe an aided diagnosis scheme for periodontal bone resorption so that the dentist can make an early diagnosis of the periodontal disease and establish the best treatment plan to increase the success of healing. Three ways of displaying the results are provided: qualitative, simple quantitative and colored-percentage quantitative views. A total of 72 pairs of in vitro radiographic images were used. The main procedure registers the images perspective projection aimed to align them in rotation and translation, and is followed by the application of a contrast correction technique. The results from the subtraction were evaluated firstly by the comparison between the actual and the digital sizes corresponding to the holes made by drills in phantoms. The mean error was 4.2%. The method was also applied to actual tooth radiographic images and could detect clearly the effect of treatment of periodontal diseases. It is dependent on the reproducibility of the process of radiographs acquisition and digitization, but the calculated mean error allows to conclude its better efficacy compared to usual procedures in this field. (author)

  10. Digital subtraction in gadolinium-enhanced MR imaging of the brain: a method to reduce contrast dosage

    International Nuclear Information System (INIS)

    Chan, J.H.M.; Tsui, E.Y.K.; Chan, C.Y.; Lai, K.F.; Cheung, Y.K.; Wong, K.P.C.; Yuen, M.K.; Chau, L.F.; Fong, D.; Mok, C.K.

    2002-01-01

    The aim of the study was to investigate the feasibility of using digital subtraction in contrast-enhanced MR imaging of the brain to reduce the MR contrast dosage without jeopardizing patient care. Fifty-two patients with intracranial lesions, either intra-axial or extra-axial, detected by computerized tomography were selected for contrast-enhanced MR imaging with half-dose and full-dose of gadopentetate dimeglumine. The half-dose unsubtracted, full-dose unsubtracted, and half-dose subtracted MR images were visually assessed by counting the number of enhancing brain lesions in the images and quantitatively analyzed by computing their lesion contrast-to-background ratios (CBR). The visual conspicuity of the half-dose subtracted MR images was comparable to that of the full-dose unsubtracted MR images (p>0.05), whereas the CBR of the half-dose subtracted images was approximately two to three times higher than that of the full-dose unsubtracted images. The half-dose subtracted T1-weighted spin-echo images might be able to replace the conventional standard-dose T1-weighted spin-echo images in MR imaging of the brain. (orig.)

  11. Feasibility study of 2D thick-slice MR digital subtraction angiography

    International Nuclear Information System (INIS)

    Ishimori, Yoshiyuki; Takeuchi, Miho; Higashimura, Kyouji; Komuro, Hiroyuki

    2000-01-01

    Conditions required to perform contrast MR digital subtraction angiography using a two-dimensional thick-slice high-speed gradient echo were investigated. The conditions in the phantom experiment included: slice profile, flip angle, imaging matrix, fat suppression, duration of IR pulse and frequency selectivity, flip angle of IR pulse and inversion time. Based on the results of the experiment, 2D thick-slice MRDSA was performed in volunteers. Under TR/TE=5.3-9/1.3-1.8 ms conditions, the requirements were a slice thick enough to include the target region, a flip angle of 10 degrees, and a phase matrix of 96 or more. Fat suppression was required for adipose-tissue-rich regions, such as the abdomen. The optimal conditions for applying the IR preparation pulse of the IR prepped fast gradient recalled echo as spectrally selective inversion recovery appeared to be: duration of IR pulse =20 ms, flip angle =100 degrees, and inversion time =40 ms. The authors concluded that it was feasible to perform 2D thick-slice MRDSA with time resolution within 1 second. (K.H.)

  12. Computed tomography versus digital subtraction angiography for the diagnosis of obscure gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Wildgruber, Moritz, E-mail: moritzwildgruber@ukmuenster.de [Institut für Röntgendiagnostik, Universitätsklinikum Regensburg, D-93053 Regensburg (Germany); Institut für klinische Radiologie, Universitätsklinikum Münster, D-48149 Münster (Germany); Wrede, Christian E. [Notfallzentrum, Helios Klinikum Berlin-Buch, D-13125 Berlin (Germany); Zorger, Niels [Institut für Radiologie, Neuroradiologie und Nuklearmedizin, Krankenhaus Barmherzige Brüder, D-93049 Regensburg (Germany); Müller-Wille, René; Hamer, Okka W. [Institut für Röntgendiagnostik, Universitätsklinikum Regensburg, D-93053 Regensburg (Germany); Zeman, Florian [Zentrum für Klinische Studien, Universitätsklinikum Regensburg, D-93053 Regensburg (Germany); Stroszczynski, Christian; Heiss, Peter [Institut für Röntgendiagnostik, Universitätsklinikum Regensburg, D-93053 Regensburg (Germany)

    2017-03-15

    Purpose: The diagnostic yield of computed tomography angiography (CTA) compared to digital subtraction angiography (DSA) for major obscure gastrointestinal bleeding (OGIB) is not known. Aim of the study was to prospectively evaluate the diagnostic yield of CTA versus DSA for the diagnosis of major OGIB. Material and methods: The institutional review board approved the study and informed consent was obtained from each patient. Patients with major OGIB were prospectively enrolled to undergo both CTA and DSA. Two blinded radiologists each reviewed the CTA and DSA images retrospectively and independently. Contrast material extravasation into the gastrointestinal lumen was considered diagnostic for active bleeding. Primary end point of the study was the diagnostic yield, defined as the frequency a technique identified an active bleeding or a potential bleeding lesion. The diagnostic yield of CTA and DSA were compared by McNemar's test. Results: 24 consecutive patients (11 men; median age 64 years) were included. CTA and DSA identified an active bleeding or a potential bleeding lesion in 92% (22 of 24 patients; 95% CI 72%–99%) and 29% (7 of 24 patients; 95% CI 12%–49%) of patients, respectively (p < 0.001). CTA and DSA identified an active bleeding in 42% (10 of 24; 95% CI 22%–63%) and 21% (5 of 24; 95% CI 7%–42%) of patients, respectively (p = 0.06). Conclusion: Due to the lower invasiveness and higher diagnostic yield CTA should be favored over DSA for the diagnosis of major OGIB.

  13. Computed tomography versus digital subtraction angiography for the diagnosis of obscure gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Wildgruber, Moritz; Wrede, Christian E.; Zorger, Niels; Müller-Wille, René; Hamer, Okka W.; Zeman, Florian; Stroszczynski, Christian; Heiss, Peter

    2017-01-01

    Purpose: The diagnostic yield of computed tomography angiography (CTA) compared to digital subtraction angiography (DSA) for major obscure gastrointestinal bleeding (OGIB) is not known. Aim of the study was to prospectively evaluate the diagnostic yield of CTA versus DSA for the diagnosis of major OGIB. Material and methods: The institutional review board approved the study and informed consent was obtained from each patient. Patients with major OGIB were prospectively enrolled to undergo both CTA and DSA. Two blinded radiologists each reviewed the CTA and DSA images retrospectively and independently. Contrast material extravasation into the gastrointestinal lumen was considered diagnostic for active bleeding. Primary end point of the study was the diagnostic yield, defined as the frequency a technique identified an active bleeding or a potential bleeding lesion. The diagnostic yield of CTA and DSA were compared by McNemar's test. Results: 24 consecutive patients (11 men; median age 64 years) were included. CTA and DSA identified an active bleeding or a potential bleeding lesion in 92% (22 of 24 patients; 95% CI 72%–99%) and 29% (7 of 24 patients; 95% CI 12%–49%) of patients, respectively (p < 0.001). CTA and DSA identified an active bleeding in 42% (10 of 24; 95% CI 22%–63%) and 21% (5 of 24; 95% CI 7%–42%) of patients, respectively (p = 0.06). Conclusion: Due to the lower invasiveness and higher diagnostic yield CTA should be favored over DSA for the diagnosis of major OGIB.

  14. Evaluation of the cardiovascular system by digital subtraction angiography in 246 patients

    Energy Technology Data Exchange (ETDEWEB)

    Higuma, Kikuhiko; Ohta, Takashi; Hiroto, Seiji

    1987-07-01

    Usefulness of intravenous digital subtraction angiography (DSA) was examined in 246 patients with cardiovascular disorders. This examination was done by centrally intravenous DSA (CIVDSA) in all patients to reduce the risks and discomforts by peripheral intravenous DSA. 1) CIVDSA could be done safely in patients aged 18 to 81 years. 2) The good diagnostic quality by CIVDSA was obtained in 81.3% of patients. These images were classified into 7 groups according to the cardiovascular system, that is, the jugular arteries, the upper extremity arteries, the thoracic aorta, the left ventricle, the abnominal aorta, the renal arteries, and the lower extremity arteries, whose rate of good diagnostic quality were 100%, 70%, 67.7%, 79.5%, 84.8%, 87%, and 71.4% respectively. 3) The poor diagnostic quality was obtained in 18.7%. 4) The severe complications were not found in any case during this examination. Our results indicate that DSA is the safe, simple and useful method to obtain the diagnostic quality image of the cardiovascular system, especially, of the occulsive arterial disease, the aortic aneurisma, the renovascular stenosis and the cardiac function of postmyocardial infarction, even in aged patients.

  15. Evaluation of the cardiovascular system by digital subtraction angiography in 246 patients

    International Nuclear Information System (INIS)

    Higuma, Kikuhiko; Ohta, Takashi; Hiroto, Seiji

    1987-01-01

    Usefulness of intravenous digital subtraction angiography (DSA) was examined in 246 patients with cardiovascular disorders. This examination was done by centrally intravenous DSA (CIVDSA) in all patients to reduce the risks and discomforts by peripheral intravenous DSA. 1) CIVDSA could be done safely in patients aged 18 to 81 years. 2) The good diagnostic quality by CIVDSA was obtained in 81.3 % of patients. These images were classified into 7 groups according to the cardiovascular system, that is, the jugular arteries, the upper extremity arteries, the thoracic aorta, the left ventricle, the abnominal aorta, the renal arteries, and the lower extremity arteries, whose rate of good diagnostic quality were 100 %, 70 %, 67.7 %, 79.5 %, 84.8 %, 87 %, and 71.4 % respectively. 3) The poor diagnostic quality was obtained in 18.7 %. 4) The severe complications were not found in any case during this examination. Our results indicate that DSA is the safe, simple and useful method to obtain the diagnostic quality image of the cardiovascular system, especially, of the occulsive arterial disease, the aortic aneurisma, the renovascular stenosis and the cardiac function of postmyocardial infarction, even in aged patients. (author)

  16. Magnetic resonance angiography compared to intra-arterial digital subtraction angiography in patients with subarachnoid haemorrhage

    International Nuclear Information System (INIS)

    Gouliamos, A.; Gotsis, E.; Vlahos, L.; Samara, C.; Kapsalaki, E.; Rologis, D.; Kapsalakis, Z.; Papavasiliou, C.

    1992-01-01

    In order to evaluate the sensitivity and specificity of magnetic resonance angiography (MRA) in spontaneous subarachnoid haemorrhage, 14 patients with recent haemorrhage verified by CT or lumbar puncture were investigated with both selective intra-arterial digital subtraction angiography (IA-DSA) and MRA by two independent teams, each having the same preangiographic information. The results were compared with each other and whenever possible (all positive cases except one) with those of surgical intervention. Seven patients were identified by MRA and IA-DSA as having a single aneurysm on the circle of Willis, 1 an aneurysm of the posterior inferior cerebellar artery 1 an aneurysm of the internal carotid artery (siphon) and 2 patients with two aneurysms on the circle of Willis. MRA and IA-DSA both failed to demonstrate aneurysms in 2 cases. Three patients had negative results on both methods and no surgical intervention was attempted. The aneurysms ranged from 0.3 to 1.5 cm in size. In most cases there was agreement between MRA and DSA, leading us to believe that, if the proper protocols are followed, MRA is a powerful alternative to other established methods in the detection of intracranial aneurysms. At this stage it will not replace IA-DSA prior to surgery, but the ability to obtain various projections using 3D MRA may improve surgical planning. (orig.)

  17. Magnetic resonance angiography compared to intra-arterial digital subtraction angiography in patients with subarachnoid haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Gouliamos, A. (Dept. of Radiology, Athens Univ. (Greece)); Gotsis, E. (Diagnostic and Research Inst. Encephalos, Athens (Greece)); Vlahos, L. (Dept. of Radiology, Athens Univ. (Greece)); Samara, C. (Dept. of Radiology, Athens Univ. (Greece)); Kapsalaki, E. (Diagnostic and Research Inst. Encephalos, Athens (Greece)); Rologis, D. (Dept. of Neurosurgery, Athens General Hospital (Greece)); Kapsalakis, Z. (Diagnostic and Research Inst. Encephalos, Athens (Greece)); Papavasiliou, C. (Dept. of Radiology, Athens Univ. (Greece))

    1992-12-01

    In order to evaluate the sensitivity and specificity of magnetic resonance angiography (MRA) in spontaneous subarachnoid haemorrhage, 14 patients with recent haemorrhage verified by CT or lumbar puncture were investigated with both selective intra-arterial digital subtraction angiography (IA-DSA) and MRA by two independent teams, each having the same preangiographic information. The results were compared with each other and whenever possible (all positive cases except one) with those of surgical intervention. Seven patients were identified by MRA and IA-DSA as having a single aneurysm on the circle of Willis, 1 an aneurysm of the posterior inferior cerebellar artery 1 an aneurysm of the internal carotid artery (siphon) and 2 patients with two aneurysms on the circle of Willis. MRA and IA-DSA both failed to demonstrate aneurysms in 2 cases. Three patients had negative results on both methods and no surgical intervention was attempted. The aneurysms ranged from 0.3 to 1.5 cm in size. In most cases there was agreement between MRA and DSA, leading us to believe that, if the proper protocols are followed, MRA is a powerful alternative to other established methods in the detection of intracranial aneurysms. At this stage it will not replace IA-DSA prior to surgery, but the ability to obtain various projections using 3D MRA may improve surgical planning. (orig.)

  18. Experience with intravenous digital subtraction angiography following shunting in 4 cases of congenital heart diseases

    Energy Technology Data Exchange (ETDEWEB)

    Higashidate, Masafumi; Konno, Susumu; Sumitomo, Naokata; Ito, Sango; Kobayashi, Hiroshi

    1985-01-01

    Intravenous digital subtraction angiography (IV-DSA) was performed in two patients with Fallot's tetralogy who underwent Blalock-Taussing operation, a patient with coarctation of the aortic arch who underwent extra-anastomic bypass between the ascending aorta and the descending aorta, and a patient with stenosis of the tricuspid valve who underwent Fontan type operation (anastomosis between the right atrium and the pulmonary artery). The conventional cardiac angiography was also performed for the comparison with IV-DSA in all patients. IV-DSA revealed the thickness of the subclavian artery anastomosed by Blaloch-Taussing operation, but failed to determine the accurate thickness of the pulmonary artery required for PA-index for radical surgery in cases of Fallot's tetralogy. Bypass from the ascending aorta to the descending aorta was well visualized by IV-DSA because the heart did not overlap on the image. In cases of Fontan type operation, IV-DSA permitted the visualization of blood flow from the right atrium to the pulmonary artery and the shape of the pulmonary artery. It is concluded that IV-DSA is a less invasive, simple technique to evaluate patients' condition following shunting for congenital heart diseases, as compared to the conventional method. (Namekawa, K.).

  19. Saving radiation dose and contrast media in intravenous digital subtraction angiography by use of bolus chasing

    International Nuclear Information System (INIS)

    Rueckforth, J.; Schuermann, K.; Vorwerk, D.; Guenther, R.W.

    1998-01-01

    Purpose: This study evaluates the dose area product, the amount of contrast media and the examination quality of the bolus chasing technique compared to the single-step technique in intravenous digital subtraction angiography. Material and Methods: 15 examinations each with bolus chasing and single-step technique were compared. The dose area product and the volume of contrast media were recorded. The examination quality was scored by two examiners. Results: With bolus chasing the volume of the administered contrast media could be decreased on average by 114 ml (43%). The difference between the dose area product of bolus chasing (722 dGy/cm 2 ) and single-step technique (1910 dGy/cm 2 ) was significant. No significant difference in examination quality was found. Conclusions: The intravenous bolus chasing technique is a practicable method. Compared to the single-step technique it allows a remarkable dose reduction and a low consumption of contrast media without restriction of examination quality. (orig.) [de

  20. Early Recanalization Postintravenous Thrombolysis in Ischemic Stroke with Large Vessel Occlusion: A Digital Subtraction Angiography Study.

    Science.gov (United States)

    Mao, Yi-Ting; Mitchell, Peter; Churilov, Leonid; Dowling, Richard; Dong, Qiang; Yan, Bernard

    2016-08-01

    We aimed to evaluate early recanalization postintravenous (i.v.) tissue plasminogen activator (t-PA) by digital subtraction angiography (DSA) in acute ischemic stroke (AIS) with large vessel occlusion (LVO). We performed baseline CT angiography to identify LVO in AIS. Recanalization pre- and post-intra-arterial therapy (IAT) was categorized to none, partial, and global recanalization (GR). Modified Rankin Scale score ≤2 at 3 months was considered a favorable outcome. Among 1610 patients with AIS, 286 received IV t-PA. Of these, 55 patients with LVO were included. The median time from IV t-PA to DSA was 120 min (interquartile range, 79-152). Recanalization post-IV t-PA was observed in seven patients (12.7%). By occlusion sites, the recanalization rates were as follows: extracranial internal carotid artery 2 of 14 (14.3%); intracranial internal carotid artery 3 of 24 (12.5%); M1 of middle cerebral artery 3 of 39 (7.7%); M2 of middle cerebral artery 1 of 40 (2.5%); vertebral artery 0 of 4; and basilar artery 0 of 7. GR post-IAT was associated with favorable outcomes (odds ratio: 8.6; 95% confidence interval, 1.5-48.0; P = 0.014). Early recanalization assessed by DSA post-IV t-PA is rarely observed in acute ischemic stroke patients with LVO. © 2016 John Wiley & Sons Ltd.

  1. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    International Nuclear Information System (INIS)

    Hanson, Eric H.; Roach, Cayce J.; Ringdahl, Erik N.; Wynn, Brad L.; DeChancie, Sean M.; Mann, Nathan D.; Diamond, Alan S.; Orrison, William W.

    2011-01-01

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  2. A LabVIEW Platform for Preclinical Imaging Using Digital Subtraction Angiography and Micro-CT.

    Science.gov (United States)

    Badea, Cristian T; Hedlund, Laurence W; Johnson, G Allan

    2013-01-01

    CT and digital subtraction angiography (DSA) are ubiquitous in the clinic. Their preclinical equivalents are valuable imaging methods for studying disease models and treatment. We have developed a dual source/detector X-ray imaging system that we have used for both micro-CT and DSA studies in rodents. The control of such a complex imaging system requires substantial software development for which we use the graphical language LabVIEW (National Instruments, Austin, TX, USA). This paper focuses on a LabVIEW platform that we have developed to enable anatomical and functional imaging with micro-CT and DSA. Our LabVIEW applications integrate and control all the elements of our system including a dual source/detector X-ray system, a mechanical ventilator, a physiological monitor, and a power microinjector for the vascular delivery of X-ray contrast agents. Various applications allow cardiac- and respiratory-gated acquisitions for both DSA and micro-CT studies. Our results illustrate the application of DSA for cardiopulmonary studies and vascular imaging of the liver and coronary arteries. We also show how DSA can be used for functional imaging of the kidney. Finally, the power of 4D micro-CT imaging using both prospective and retrospective gating is shown for cardiac imaging.

  3. Detection and characterization of intracranial aneurysms: magnetic resonance angiography versus digital subtraction angiography

    International Nuclear Information System (INIS)

    Shahzad, R.; Younas, F.

    2011-01-01

    Objective: To compare magnetic resonance angiography (MRA) with Intra-arterial digital subtraction angiography (IA-DSA) in detection and characterization of intracranial aneurysms. Study Design: Comparative cross-sectional study. Place and Duration of Study: Department of Diagnostic Imaging, Lahore General Hospital, Lahore, from January to June 2007. Methodology: Thirty patients presented with aneurysmal subarachnoid haemorrhage (SAH) and focal neurological signs were selected by convenience sampling. Three dimensional time of flight (3D TOF) MRA using maximum intensity projection (MIP) was performed on all patients along with DSA. Results of 3D TOF MRA were compared with those of IA-DSA taking IA-DSA as Gold standard. Results: Out of 30 patients 14 (46.7%) were males and 16 (53.3%) were females with mean age of 41+-14.1 years. MRA detected 29 out of 30 aneurysmal lesions with sensitivity of 96.7%. Regarding characterization of aneurysms results of MRA were comparable to those of IA-DSA. Conclusion: 3D TOF MRA technique showed a high sensitivity in this study. This technique can be used as a non-invasive screening test for intracranial aneurysms and as a suitable alternative primary examination to IA-DSA prior to aneurysmal surgery. (author)

  4. Headache-like Subarachnoid Hemorrhage After Digital Subtraction Angiography: A Case Report

    Directory of Open Access Journals (Sweden)

    Fettah Eren

    2018-03-01

    Full Text Available Subarachnoid hemorrhage (SAH is a clinical condition with acute-onset, sudden, and severe headache. In addition to headache, severe nausea, vomiting, dizziness, confusion, agitation, focal neurologic deficits, and hypertension can be detected. Findings of meningeal irritation may accompany to these clinical features, 6-24 hours after the hemorrhage. Digital subtraction angiography (DSA is used for surgical or endovascular treatment planning in order to identify vascular abnormalities, in addition to other imaging studies. After DSA, the frequency of all neurologic complications is between 0.2% and 4.5%. Headache may occur after DSA in an average 50% of patients. This rate is especially higher in female patients. Headache types are usually classified as migraine, tension or postoperative atypical headaches The incidence of severe headache after DSA is low. Vascular wall rupture should be considered first in severe headache after the procedure. It should also be kept in mind that after all other secondary causes are excluded; SAH-like headaches after DSA can be detected

  5. Intravenous vs. left ventricular injection of ionic contrast material: hemodynamic implications for digital subtraction angiography

    International Nuclear Information System (INIS)

    Mancini, G.B.; Ostrander, D.R.; Slutsky, R.A.; Shabetai, R.; Higgins, C.B.

    1983-01-01

    Because of the increased use of intravenous injection of contrast material for the evaluation of cardiac structure and function by digital subtraction techniques, a study was done to assess the hemodynamic effects of contrast material when used in this fashion in man. In 10 patients, with each serving as his own control, the effects of intravenous and intraventricular injections of sodium meglumine diatrizoate (Renografin 76) in the same dose were compared. There was no difference between these two methods with respect to changes in pulmonary wedge pressures, systemic pressures, and pulmonary vascular resistance. The elevation of mean pulmonary artery and right atrial pressure was greater after the intraventricular injection (p <0.05). The elevated cardiac output and systemic vascular resistance returned to control values somewhat more quickly after the intravenous injection (p<0.001 and p<0.05, respectively); and the increase in cardiac output was greater after the intravenous injection at 1 min (p<0.05), but less than after the intraventricular injection at 2 min (p<0.05). Despite the detection of these statistically significant differences, the magnitude and timing of these differences are too small to justify the notion that imaging by intravenous injections of standard ionic contrast media provides any substantial hemodynamic benefits or decreased risk to the patient

  6. Diagnostic value of digital subtraction angiography (DSA) using TOSHIBA DIGIFORMER X in the cerebrospinal vascular diseases

    International Nuclear Information System (INIS)

    Ishikawa, Tatsuya; Nakagawa, Yoku; Sawamura, Yutaka; Kobayashi, Nobuaki; Nagashima, Masafumi; Kitaoka, Ken-ichi; Kitagawa, Michio; Itoh, Terufumi; Ohsato, Takao.

    1987-01-01

    Using TOSHIBA Digiformer X, digital subtraction angiography (DSA) was performed in 286 patients, in whom 229 patients of cerebro-spinal vascular disease was included. The authors emphasize the usefulness of DSA in cerebro-spinal vascular disease in relation to conventional angiography. DSA taken by single small dose injection of contrast medium into the ascending aorta clearly demonstrates not only aortic arch and thoracic major vessels, but also cervical vessels and all intracranial vessels. Therefore, we could rapidly understand gross dynamics of the circulation and obtain useful informations prior to catheterization to the selective artery. This advantage of DSA was particularly useful for occlusive vascular diseases. Gradual injection of small dose of contrast medium obviously reduced recoiling of the catheter tip, which enabled the selective angiography with setting of the tip of the catheter at the entrance of cervical major vessels without its sufficient inserion into the selective vessels. This advantage is particularly beneficial for the patients with severe arteriosclerosis who was found to be difficult for selective catheterization. In our experience, demonstration of a presence of aneurysm by DSA was possible in almost all cases of subarachnoid hemorrhage, although spatial resolution of DSA is said to be inferior to the conventional angiography. Real time display of DSA decreased the time required for examination and enabled repeated angiography. This advantage of DSA is especially useful for the patients with spinal arterio-venous malformation and thoracic outlet syndrome. (author)

  7. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

    2011-05-15

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  8. Value of infusion-DSA (Digital Subtraction Angiography) in diagnosis of primary hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kwon, Jeong Mi; Kim, So Sun; Huh, Jin Do; Kim, Ho Joon; Chun, Byung Hee; Joh, Young Duk

    1991-01-01

    In order to evaluate diagnostic effectiveness of the infusion-study, the authors prospectively evaluated hepatic digital subtraction angiography of bolus and infusion studies in 71 patients with hepatocellular carcinoma. In contrast to Bolus-DSA, which involves a 2 second injection of 10cc of contrast medium, the Infusion-DSA uses a protracted (10sec) injection, a lower injection rate, and larger total dose of contrast medium (20cc). The information yield of arterial and capillary phases of Infusion-DSA was compared with that of Bolus-DSA and graded as 'improved(+)', 'equivalent( ± )', or 'poor(-)'. Also, the contribution of Infusion-DSA to the diagnosis was classified into one of five in a graded system. In 29 hepatocellular patients, the Infusion-DSA was helpful in detecting daughter nodules, fibrous capsule and arteriovenous shunt. Infusion-DSA is a useful complementary technique in the diagnosis of hepatocellular carcinoma and was also helpful in determining the selection of the therapeutic modality of hepatocellular carcinoma

  9. Experience with intravenous digital subtraction angiography following shunting in 4 cases of congenital heart diseases

    International Nuclear Information System (INIS)

    Higashidate, Masafumi; Konno, Susumu; Sumitomo, Naokata; Ito, Sango; Kobayashi, Hiroshi

    1985-01-01

    Intravenous digital subtraction angiography (IV-DSA) was performed in two patients with Fallot's tetralogy who underwent Blalock-Taussing operation, a patient with coarctation of the aortic arch who underwent extra-anastomic bypass between the ascending aorta and the descending aorta, and a patient with stenosis of the tricuspid valve who underwent Fontan type operation (anastomosis between the right atrium and the pulmonary artery). The conventional cardiac angiography was also performed for the comparison with IV-DSA in all patients. IV-DSA revealed the thickness of the subclavian artery anastomosed by Blaloch-Taussing operation, but failed to determine the accurate thickness of the pulmonary artery required for PA-index for radical surgery in cases of Fallot's tetralogy. Bypass from the ascending aorta to the descending aorta was well visualized by IV-DSA because the heart did not overlap on the image. In cases of Fontan type operation, IV-DSA permitted the visualization of blood flow from the right atrium to the pulmonary artery and the shape of the pulmonary artery. It is concluded that IV-DSA is a less invasive, simple technique to evaluate patients' condition following shunting for congenital heart diseases, as compared to the conventional method. (Namekawa, K.)

  10. DIAGNOSTIC ACCURACY OF MAGNETIC RESONANCE ANGIOGRAPHY FOR UNRUPTURED CEREBRAL ANEURYSMS IN CORRELATION WITH DIGITAL SUBTRACTION ANGIOGRAPHY

    Directory of Open Access Journals (Sweden)

    Aleksandra Aracki-Trenkić

    2015-09-01

    Full Text Available Intracranial aneurysm is a focal, abnormal dilation of an artery of the brain. Magnetic resonance angiography (MRA is a non-invasive technique for vascular imaging and is thus widely used for screening for intracranial vascular lesions. The aim of the study was to show the diagnostic accuracy of 3D Time-of-Flight (3D TOF MRA in the detection of unruptured cerebral aneurysms with the use of digital subtraction angiography (DSA as the gold standard. A total of 2.612 consecutive patients underwent 3DTOF MRA. It showed unruptured aneurysms in 94 (3.6% patients. They included 68 women and 26 men ranging in age from 29 to 76 years (mean, 52.5 years. Twenty-six of them, 20 women and 6 men, underwent DSA. The Mann-Whitney U test was used for the correlation of size. Fisher’s test was used for the correlation of location. The statistical level of significance was set at p0.05 of aneurysms between TOF MRA and DSA. MRA is an accurate and non-invasive method for diagnosis of unruptured intracranial aneurysms. The results of study show the compatibility of MRA findings, the location and the size of an aneurysm in comparison with the “gold standard” – cerebral DSA.

  11. Comparison of 3D magnetic resonance imaging and digital subtraction angiography for intracranial artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Eun; Jung, Seung Chai; Kim, Ho Sung; Choi, Choong-Gon; Kim, Sang Joon; Lee, Deok Hee [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Lee, Sang Hun; Kwon, Sun U.; Kang, Dong-Wha; Kim, Jong S. [University of Ulsan College of Medicine, Department of Neurology, Ulsan (Korea, Republic of); Jeon, Ji Young [Gachon University, Department of Radiology, Gil Medical Center, Incheon (Korea, Republic of); Lee, Ji Ye [Soonchunhyang University Bucheon Hospital, Department of Radiology, Bucheon (Korea, Republic of); Kim, Seon-Ok [University of Ulsan College of Medicine, Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, Seoul (Korea, Republic of)

    2017-11-15

    To compare three-dimensional high-resolution magnetic resonance imaging (3D HR-MRI) and digital subtraction angiography (DSA) for diagnosing and evaluating stenosis in the entire circle of Willis. The study included 516 intracranial arteries from 43 patients with intracranial artery stenosis (ICAS) who underwent both 3D HR-MRI and DSA within 1 month. Two readers independently diagnosed atherosclerosis, dissection, moyamoya disease and vasculitis, rated their diagnostic confidence for each vessel and measured the luminal diameters. Reference standard was made from clinico-radiologic diagnosis. Diagnostic accuracy, diagnostic confidence, the degree of stenosis and luminal diameter were assessed and compared between both modalities. For atherosclerosis, 3D HR-MRI showed better diagnostic accuracy (P =.03-.003), sensitivity (P =.006-.01) and positive predictive value (P ≤.001-.006) compared to DSA. Overall, the readers were more confident of their diagnosis of ICAS when using 3D HR-MRI (reader 1, P ≤.001-.007; reader 2, P ≤.001-.015). 3D HR-MRI showed similar degree of stenosis (P >.05) and higher luminal diameter (P <.05) compared to DSA. 3D HR-MRI might be useful to evaluate atherosclerosis, with better diagnostic confidence and comparable stenosis measurement compared to DSA in the entire circle of Willis. (orig.)

  12. Usefulness of digital subtraction angiography in ischemic cerebral vascular disease: relationship to age and gender

    Energy Technology Data Exchange (ETDEWEB)

    Klein, U; Hall, D; Vogt, U

    1986-01-01

    In 500 consecutive patients, intravenous digital subtraction angiography of the extracerebral arteries was carried out. 63.2% of the patients were males, 36.8% females. A total of 37.4% of the patients were 59 years of age or less (69.5% male, 30.5% female). 62.6% were 60 years and older (59.5% male, 40.5% female). 30.6% of all patients were over the age of 70 years (51% male, 49.0% female). 54% of all patients had pathologic findings: of these, 67% were males and 33.0% females. In 56 patients (11.2%), the carotis bifurcation was not adequately visualized. Of 214 patients with lesions of the internal carotid artery, 59.3% had unilateral stenosis. Unilateral occlusion of the carotis was found in 18.7%, bilateral stenosis of the internal carotid artery as well as internal carotid stenosis with contralateral occlusion was found in 10.3%. Additional lesions in the remaining extracerebral vessels were found in 34.6% (stenosis or occlusion of the external carotid artery, vertebral arteries or the subclavian artery, including subclavian steal syndrome).

  13. Describable ability of blood vessels in head and neck by intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Minakuchi, Kazuo; Takada, Keiji; Nakamura, Kenji

    1989-01-01

    Ninety-four patients with various symptoms of the head and neck were studied by intravenous digital subtraction angiography (IV-DSA). Abnormal findings were obesrved in 12 patients; one with aneurysm in the left internal carotid artery, and 11 with obstruction in the right middle cerebral artery (2), the right internal carotid artery (one), the left subclavian artery (one), the right vertebral artery (6), and the left vertebral artery (one). Motion artifacts were observed in 2 patients. The vertebral arteries were bilaterally equal in size in 42%, and the left vertebral artery was bigger than the right one in 38%. The superior sagittal dural sinus was clearly imaged in 94%. The incidence of excellent images was higher in the right sided than the left sided vein -- 85% vs 50% for the transverse dural sinus, 84% vs 54% for the sigmoid dural sinus, and 88% vs 57% for the jugular vein. Sites of excellent images were all of the dural sinuses and veins (37 cases), confined to the right side (37), confined to the left side (8), and undefined (12). (N.K.)

  14. Analysis of Radiation Effects in Digital Subtraction Angiography of Intracranial Artery Stenosis.

    Science.gov (United States)

    Guo, Chaoqun; Shi, Xiaolei; Ding, Xianhui; Zhou, Zhiming

    2018-04-21

    Intracranial artery stenosis (IAS) is the most common cause for acute cerebral accidents. Digital subtraction angiography (DSA) is the gold standard to detect IAS and usually brings excess radiation exposure to examinees and examiners. The artery pathology might influence the interventional procedure, causing prolonged radiation effects. However, no studies on the association between IAS pathology and operational parameters are available. A retrospective analysis was conducted on 93 patients with first-ever stroke/transient ischemic attack, who received DSA examination within 3 months from onset in this single center. Comparison of baseline characteristics was determined by 2-tailed Student's t-test or the chi-square test between subjects with and without IAS. A binary logistic regression analysis was performed to determine the association between IAS pathology and the items with a P value 42 with IAS and 51 without IAS) in this study. The 2 groups shared no significance of the baseline characteristics (P > 0.05). We found a significantly higher total time, higher kerma area product, greater total dose, and greater DSA dose in the IAS group than in those without IAS (P IAS pathology (P 0.05). IAS pathology would indicate a prolonged total time of DSA procedure in clinical practice. However, the radiation effects would not change with pathologic changes. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Clinical application of dynamic digital subtraction angiography in cerebrovascular ischemic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Yoshifumi; Nonaka, Nobuhito; Matsukado, Yasuhiko; Takahashi, Mutsumasa

    1987-09-01

    Dynamic intravenous digital subtraction angiography (IV-DSA) was performed in 37 patients with cerebrovascular ischemic diseases. The time density curve of IV-DSA was analysed, and peak time, mean transit time and mode of transit time were obtained in each patient. On the basis of these values, cerebral perfusion was classified into low, normal and high perfusion patterns. Normal perfusion pattern was noted in 40% of patients with transient ischemic attack (TIA) and 7 % of patients with cerebral infarction. Low perfusion pattern was observed in 60 % of patients with TIA and 87 % of patients with cerebral infarction. High perfusion pattern was encountered only in 7 % of patients with cerebral infarction. In ischemic patients with moyamoya disease, extremely prolonged cerebral circulation time was evidenced by the presence of a flat or uphill type of the time density curve. This finding well correlated with decreased cerebral blood flow on single photon emission tomography. These findings suggest that the analysis of dynamic DSA is very important and useful in the clinical evaluation of patients with cerebrovascular ischemic diseases.

  16. Intravenous digital subtraction angiography in the assessment of patients with left to right shunts before and after surgical correction

    International Nuclear Information System (INIS)

    Yiannikas, J.; Moodie, D.S.; Gill, C.C.; Sterba, R.; McIntyre, R.; Buonocore, E.

    1984-01-01

    Pre- and postoperative structural changes and pulmonary to systemic flow (QP/QS) ratios were assessed using digital angiography in 34 patients documented to have a left to right shunt at cardiac catheterization. There were 16 men and 18 women whose ages ranged from 4 months to 60 years. The radiographic single mask mode was used for all digital subtraction angiographic studies with a typical radiographic sequence being 80 to 100 kV, 5 to 10 mA/frame at six frames/s for 15 seconds. Renografin-76 was used as a bolus injection at 0.5 to 1.0 ml/kg via an arm vein in most patients. The level of the left to right shunt and any associated anomalies were noted and compared with results from cardiac catheterization. Digital subtraction angiographic flow curves were generated from the pulmonary arteries, and QP/QS ratios were calculated pre- and postoperatively using the gamma variate fit method and compared with the QP/QS ratio from first pass radionuclide studies. A strong correlation between preoperative digital subtraction angiographically derived QP/QS ratio and radionuclide-derived QP/QS ratio was found, with an r value equal to 0.89, p less than 0.0001. Postoperatively, all patients had a QP/QS ratio less than 1.2:1.0 for both digital subtraction angiography and radionuclide studies. The level of left to right shunt was accurately assessed in all patients, and its absence observed postoperatively. Associated anomalies, such as a persistent left superior vena cava, coarctation of the aorta and partial anomalous venous return, were identified in all cases

  17. Evaluation of cerebral intravascular blood flow by time density curve study of intravenous digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Imamura, Toru; Kogure, Kyuya (Tohoku Univ., Sendai (Japan). School of Medicine); Sekine, Teiko; Satoh, Kei; Endoh, Minoru; Tsuburaya, Kenji; Hoshi, Akihiko

    1992-01-01

    Time density curve (TDC) can be reconstructed from the data of intravenous digital subtraction angiography (IVDSA). We evaluated peak time (PT) and modal transit time (MOTT) of the TDC as the probable indicator of cerebral intravascular blood flow. Cerebral IVDSA and single photon emission CT (SPECT) were performed on 12 patients with ischemic cerebrovascular disease, which consisted of 3 internal carotid artery (ICA) occlusions, one middle cerebral artery (MCA) occlusion, one anterior cerebral artery (ACA) branch occlusion and 7 lacunar infarctions. We classified former 4 patients as occlusion group and latter 8 as reference group. In 3 patients (2 ICA and one MCA occlusions), SPECT study revealed definite hypoaccumulation in the MCA territory of occlusive side. Two regions of interest (ROI) were placed on the territories of right and left middle cerebral arteries in the frontal view of cerebral IVDSA. Digital data processor fitted {gamma} curve to the TDC of each ROI, and calculated PT and MOTT. The absolute lateralities of PT and MOTT of MCA territory was significantly (p<0.05) larger in occlusion group than reference group. Patients with hypoaccumulation in SPECT had significantly (p<0.02) larger laterality of MOTT than patients with isoaccumulation. One ICA occluded patient without hypoaccumulation in corresponding MCA territory had relatively small laterality of MOTT similar to the patients of ACA branch occlusion and lacunar infarction. These results suggest that PT and MOTT are possible to detect the laterality of the intravascular blood flow in MCA territories caused by major artery occlusion. Cerebral TDC study of IVDSA may be useful in some clinical therapeutic situations such as hemodilution or intra-arterial thrombolysis, and worth further clinical evaluation. (author).

  18. The comparative study on diagnostic validity of cerebral aneurysm by computed tomography angiography versus digital subtraction angiography after subarachnoid hemorrhage

    Directory of Open Access Journals (Sweden)

    Masih Saboori

    2011-01-01

    Full Text Available Background: In order to declare the preoperative diagnostic value of brain aneurysms, two radiological modalities, computed tomographic angiography and digital subtraction angiography were compared. Methods: In this descriptive analytic study, diagnostic value of computed tomographic angiography (CTA was com-pared with digital subtraction angiography (DSA. Sensitivity, specificity, positive and negative predictive values were calculated and compared between the two modalities. All data were analyzed with SPSS software, version 16. Results: Mean age of patients was 49.5 ± 9.13 years. 57.9 % of subjects were female. CTA showed 89% sensitivity and 100% specificity whereas DSA demonstrated 74% sensitivity and 100% specificity. Positive predictive value of both methods was 100%, but negative predictive value of CTA and DSA was 85% and 69%, respectively. Conclusions: Based on our data, CTA is a valuable diagnostic modality for detection of brain aneurysm and su-barachnoid hemorrhage.

  19. Multi-section CT angiography compared with digital subtraction angiography in diagnosing major arterial hemorrhage in inflammatory pancreatic disease

    International Nuclear Information System (INIS)

    Hyare, Harpreet; Desigan, Sharmini; Nicholl, Helen; Guiney, Michael J.; Brookes, Jocelyn A.; Lees, William R.

    2006-01-01

    Purpose: Major arterial hemorrhage is an uncommon but serious complication of pancreatitis with high morbidity and mortality. Digital subtraction angiography (DSA) has long been the gold standard for the detection of a visceral artery pseudoaneurysm or for the site of active bleeding in patients with pancreatitis. Multi-section CT angiography is a minimally invasive technique which can provide high-resolution and high-contrast images of the arterial lumen and wall, with a much lower risk of complication and morbidity compared to DSA. The aim of this study was to determine the accuracy of multi-section CT angiography for the diagnosis of arterial complications of inflammatory pancreatitic disease. Materials and methods: A retrospective analysis of all patients undergoing visceral angiography for major bleeding as a complication of pancreatitis between 1998 and 2004 was performed. Twenty-nine studies in 25 patients (20 males, 5 females) with a mean age of 50.9 years (range 11-67 years) were identified where multi-section CT angiography was performed in the 24 h preceding the digital subtraction angiogram. Results: Digital subtraction angiography detected a pseudoaneurysm or contrast extravasation in 19 studies and no bleeding was demonstrated in 9 studies. CT angiography correctly identified the site and type of bleeding in 18 of the 19 positive studies. CT angiography detected extravasation of contrast in one study that was not demonstrated on digital subtraction angiography. The sensitivity and specificity for multi-section CT angiography for the detection of major arterial bleeding on a background of pancreatitis were 0.947 and 0.900, respectively. Conclusion: Multi-section CT angiography is a sensitive and accurate technique for the detection of major arterial hemorrhage in inflammatory pancreatic disease and should be considered as the first investigation in the management of these patients

  20. Comparative study of conducting iliac angioplasties with digital subtraction and conventional angiography. Incidence on true (consumable) costs

    International Nuclear Information System (INIS)

    Brenot, P.; Raynaud, A.; Pernes, J.M.; Parola, J.L.; Gaux, J.C.

    1986-01-01

    Differences in time and cost were evaluated between the performance of iliac angioplasty with conventional (AC) and digital subtraction (AN) angiography, after a total of 27 angioplasties (13 with AC and 14 with AN). Excluding amortization of material and personnel costs, findings confirmed a certain number of advantages for AN: gain in time of about 34%, decrease of about 14% in charges, and notably of 83% in expenditure on films and 50% on contrast media [fr

  1. Detection of intracranial aneurysms with 64 channel multidetector row computed tomography: Comparison with digital subtraction angiography

    International Nuclear Information System (INIS)

    Pozzi-Mucelli, Fabio; Bruni, Stefano; Doddi, Marco; Calgaro, Antonio; Braini, Massimiliano; Cova, Maria

    2007-01-01

    Purpose: To compare the contribution of 64 channel multidetector row computed tomography angiography (64MDCT-angiography) with digital subtraction angiography (DSA) in the detection of intracranial aneurysms. Methods and materials: Twenty-nine patients (10 males and 19 females, age: 40-84 years; average: 61.9 years) with clinical and imaging findings strongly suggesting the presence of subaracnoid hemorrhage underwent 64MDCT-angiography and DSA with a short interval between the two examinations (less than 12 h-5 days). CT parameters were: 64 mm x 0.5 mm collimation, pitch-0.828 and helical pitch-53. DSA were performed with standard technique (four vessel catheterization) and multiple projections. Axial CT scans as well as maximum intensity projection, volume rendering and multiplanar reformations and angiographic views were independently reviewed by four readers (two for 64MDCT-angiography and two for DSA). Consensus was reached for discordant cases. DSA was considered as the standard of reference. Results: In 29 patients, 28 aneurysms were found (14 patients had 1 aneurysm, 4 patients had 2 aneurysms and 2 patients had 3 aneurysms; in 9 patients no aneurysm were found). 64MDCT-angiography detected 26/28 aneurysms. No false-positive sites were recognized. The sensitivity, specificity, positive and negative predictive values and diagnostic accuracy were, respectively, 92.8, 100, 100, 99.4 and 99.5%. Conclusions: 64MDCT-angiography is helpful in detecting intracranial aneurysms with results similar to those of DSA but with less discomfort and risks for the patients and can be considered for the first line imaging technique. Conventional angiography is still needed in doubtful cases or negative MDCT-angiography associated with a strong clinical suspect

  2. Intravenous digital subtraction angiography and helical computed tomography in evaluation of living renal donors

    International Nuclear Information System (INIS)

    Watarai, Yoshihiko; Usuki, Tomoaki; Takeuchi, Ichiro; Nonomura, Katsuya; Koyanagi, Tomohiko; Kubo, Kozo; Hirano, Tetsuo; Togashi, Masaki; Ohashi, Nobuo

    2001-01-01

    The present study was carried out to evaluate the accuracy of helical computed tomography (CT) and intravenous digital subtraction angiography (IV-DSA) on anatomical assessment of renal vasculature for living renal donors. Forty-two healthy potential renal donors were prospectively evaluated and 35 subsequently underwent donor nephrectomy after helical CT and IV-DSA evaluation. The vascular and non-vascular findings were compared between the findings on helical CT, IV-DSA and surgery. Ten prehilar branches and five accessory renal arteries were found at nephrectomy. Overall, operative findings agreed with the findings by IV-DSA in 89% and by helical CT in 83%. In delineating accessory arteries, IV-DSA had a sensitivity of 60% and specificity of 97%, whereas helical CT had a sensitivity of 40% and specificity of 100%. In delineating prehilar branches, IV-DSA had a sensitivity of 90% and specificity of 100%, whereas helical CT had a sensitivity of 70% and specificity of 100%. Accessory arteries and prehilar branches that were not detected by helical CT or IV-DSA, were less than 2 mm in diameter and did not require vascular reconstruction. Renal veins were delineated in 63% by IV-DSA, whereas they were clearly imaged by helical CT in all cases, including a case with a circumaortic renal vein. Non-vascular findings were obtained in 64% by helical CT, including two renal tumors. None of these findings were obtained by IV-DSA. Helical CT and IV-DSA provide comparably sufficient information on renal artery vasculature. However, helical CT provides significantly more information on venous and non-vascular findings as a single-imaging modality. (author)

  3. Pure and diluted contrast medium in the evaluation of portal venous system with digital subtraction angiography

    International Nuclear Information System (INIS)

    Gattoni, F.; Baldini, V.; Pozzato, C.; Nessi, R.; Raiteri, R.; Uscenghi, C.; Opocher, E.; Santambrogio, R.

    1990-01-01

    We report the results of intra-arterial digital subtraction angiography (DSA) in 100 patients with portal hypertension. The portal venous system was evaluated; all patients underwent angiography of the celiac and superior mesenteric arteries before surgery. Forty-four of them were also examined after Warren splenorenal shunts. Therefore, a total of 144 exams was evaluated. The authors always employed low-osmolality ionic and non-ionic contrast media (iodine concentration: 300-350 mg/ml). In 70 cases pure contrast medium was injected (20/25 ml): in the extant 74 cases it was diluted with an equal volume of saline solution (osmolality and iodine concentration reduced by 50%). Intra-arterial DSA always visualized portal venous system, collateral circulation, shunt location and postoperative changes. The mayor advantage of intra-arterial DSA is the smaller amount of contrast medium injected, so that local and systemic side effects are rare. According to our experience, it is best to dilute the contrast medium and inject the same amount as in conventional angiography, at the same rate. Other well-known advantages of intra-arterial DSA are quicker execution, less injury to arteries using smaller caliber catheters, and low cost. The major disadvantage of intra-arterial DSA, as it appeared also in our study, is the field size of the intensifier, which in our case was limited to 6-9 inches. This is an insufficient coverage for the whole portal system to be studied, and some contrast medium injections become therefore necessary. An average of 3 injections were given to each patient. This problem reduces the advantage of less contrast medium per injection. At any rate, even though intra-arterial DSA exhibits this limitation, it can nevertheless yield important information in the pre- and postoperative evaluation of patients with portal hypertension

  4. Comparisons of images simultaneously documented by digital subtraction coronary arteriography and cine coronary arteriography

    International Nuclear Information System (INIS)

    Kimura, Koji; Takamiya, Makoto; Yamamoto, Kazuo; Ohta, Mitsushige; Naito, Hiroaki

    1988-01-01

    Using an angiography apparatus capable of simultaneously processing digital subtraction angiograms and cine angiograms, the diagnostic capabilities of both methods for the coronary arteries (DSCAG and Cine-CAG) were compared. Twenty stenotic lesions of the coronary arteries of 11 patients were evaluated using both modalities. The severity of stenosis using DSCAG with a 512x512x8 bit matrix was semiautomatically measured on the cathode ray tube (CRT) based on enlarged images on the screen of a Vanguard cine projector which were of the same size as those of or 10 times larger than images of Cine-CAG. The negative and positive hard copies of DSCAG images were also compared with those of Cine-CAG. The correlation coefficients of the severity of stenosis by DSCAG and Cine-CAG were as follows: (1) the same size DSCAG images on CRT to Cine-CAG, 0.95, (2) 10 times enlarged DSCAG images on CRT to Cine-CAG, 0.96, and (3) the same size DSCAG images on negative and positive hard copies to Cine-CAG, 0.97. The semiautomatically measured values of 10 times enlarged DSCAG images on CRT and the manually measured values of the same size negative and positive DSCAG images in hard copy closely correlated with the values measured using Cine-CAG. When the liver was superimposed in the long-axis projection, the diagnostic capabilities of DSCAG and Cine-CAG were compared. The materials included 10 left coronary arteriograms and 11 right coronary arteriograms. Diagnostically, DSCAG was more useful than Cine-CAG in the long-axis projection. (author)

  5. Quantitative blood flow measurements in the small animal cardiopulmonary system using digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lin Mingde; Marshall, Craig T.; Qi, Yi; Johnston, Samuel M.; Badea, Cristian T.; Piantadosi, Claude A.; Johnson, G. Allan [Department of Radiology, Center for In Vivo Microscopy and Department of Biomedical Engineering, Duke University Medical Center, Box 3302, Durham, North Carolina 27710 (United States); Division of Pulmonary and Critical Care Medicine and Center for Hyperbaric Medicine and Environmental Physiology, Duke University Medical Center, Box 3823, Durham, North Carolina 27710 (United States); Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Box 3302, Durham, North Carolina 27710 (United States); Department of Radiology, Center for In Vivo Microscopy and Department of Biomedical Engineering, Duke University Medical Center, Box 3302, Durham, North Carolina 27710 (United States); Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Box 3302, Durham, North Carolina 27710 (United States); Division of Pulmonary and Critical Care Medicine and Center for Hyperbaric Medicine and Environmental Physiology, Duke University Medical Center, Box 3823, Durham, North Carolina 27710 (United States); Department of Radiology, Center for In Vivo Microscopy and Department of Biomedical Engineering, Duke University Medical Center, Box 3302, Durham, North Carolina 27710 (United States)

    2009-11-15

    Purpose: The use of preclinical rodent models of disease continues to grow because these models help elucidate pathogenic mechanisms and provide robust test beds for drug development. Among the major anatomic and physiologic indicators of disease progression and genetic or drug modification of responses are measurements of blood vessel caliber and flow. Moreover, cardiopulmonary blood flow is a critical indicator of gas exchange. Current methods of measuring cardiopulmonary blood flow suffer from some or all of the following limitations--they produce relative values, are limited to global measurements, do not provide vasculature visualization, are not able to measure acute changes, are invasive, or require euthanasia. Methods: In this study, high-spatial and high-temporal resolution x-ray digital subtraction angiography (DSA) was used to obtain vasculature visualization, quantitative blood flow in absolute metrics (ml/min instead of arbitrary units or velocity), and relative blood volume dynamics from discrete regions of interest on a pixel-by-pixel basis (100x100 {mu}m{sup 2}). Results: A series of calibrations linked the DSA flow measurements to standard physiological measurement using thermodilution and Fick's method for cardiac output (CO), which in eight anesthetized Fischer-344 rats was found to be 37.0{+-}5.1 ml/min. Phantom experiments were conducted to calibrate the radiographic density to vessel thickness, allowing a link of DSA cardiac output measurements to cardiopulmonary blood flow measurements in discrete regions of interest. The scaling factor linking relative DSA cardiac output measurements to the Fick's absolute measurements was found to be 18.90xCO{sub DSA}=CO{sub Fick}. Conclusions: This calibrated DSA approach allows repeated simultaneous visualization of vasculature and measurement of blood flow dynamics on a regional level in the living rat.

  6. Quantitative blood flow measurements in the small animal cardiopulmonary system using digital subtraction angiography

    International Nuclear Information System (INIS)

    Lin Mingde; Marshall, Craig T.; Qi, Yi; Johnston, Samuel M.; Badea, Cristian T.; Piantadosi, Claude A.; Johnson, G. Allan

    2009-01-01

    Purpose: The use of preclinical rodent models of disease continues to grow because these models help elucidate pathogenic mechanisms and provide robust test beds for drug development. Among the major anatomic and physiologic indicators of disease progression and genetic or drug modification of responses are measurements of blood vessel caliber and flow. Moreover, cardiopulmonary blood flow is a critical indicator of gas exchange. Current methods of measuring cardiopulmonary blood flow suffer from some or all of the following limitations--they produce relative values, are limited to global measurements, do not provide vasculature visualization, are not able to measure acute changes, are invasive, or require euthanasia. Methods: In this study, high-spatial and high-temporal resolution x-ray digital subtraction angiography (DSA) was used to obtain vasculature visualization, quantitative blood flow in absolute metrics (ml/min instead of arbitrary units or velocity), and relative blood volume dynamics from discrete regions of interest on a pixel-by-pixel basis (100x100 μm 2 ). Results: A series of calibrations linked the DSA flow measurements to standard physiological measurement using thermodilution and Fick's method for cardiac output (CO), which in eight anesthetized Fischer-344 rats was found to be 37.0±5.1 ml/min. Phantom experiments were conducted to calibrate the radiographic density to vessel thickness, allowing a link of DSA cardiac output measurements to cardiopulmonary blood flow measurements in discrete regions of interest. The scaling factor linking relative DSA cardiac output measurements to the Fick's absolute measurements was found to be 18.90xCO DSA =CO Fick . Conclusions: This calibrated DSA approach allows repeated simultaneous visualization of vasculature and measurement of blood flow dynamics on a regional level in the living rat.

  7. Decreasing radiation doses in digital subtraction angiographies consecutively performed by trainees

    International Nuclear Information System (INIS)

    Xu, G.; Zhao, W.; Zheng, L.; Fan, X.; Yin, Q.; Liu, X.

    2012-01-01

    Digital subtraction angiography (DSA) performed by trainees may be related to increased radiation exposure. This study was aimed to investigate and quantify this learning effect, with fluoroscopy time and dose-area product (DAP) as parameters. We collected procedure data of the first to the fortieth cerebral DSA consecutively performed by 13 trainees in a training centre. DAP, procedure time, fluoroscopy time, number of cine-frames of the first 20 DSA procedures performed by these trainees were compared with that of the second 20 procedures. There was no significant difference concerning the procedure time between the first and the second 20 procedures (56.3 ±29.5 vs 51.5±20.2 min, p = 0.113). Numbers of cine-frames were very similar between the first and the second 20 procedures (750.7 ±290.3 vs 744.5 ±188.7, p = 0.830). Fluoroscopy time of the first 20 procedures was significantly longer than that of the second 20 procedures (17.8 ±15.4 vs 12.6 ±9.0, p = 0.001). DAP of the first 20 procedures was significantly higher than that of the second 20 procedures (6.4 ±4.9 vs 3.8 ±1.8, p < 0.001). DAP was correlated significantly with the performer's experience (R = -0.288, p < 0.001). There exists a learning effect of radiation exposure during cerebral DSA procedures performed by trainees. The learning effect is significant during the first 20 procedures, and becomes insignificant after 20 procedures. Insufficient catheter skills in novice trainees may be one reason for this effect. (authors)

  8. Value and limitation of digital subtraction angiography for assessment of myocardial perfusion with varying coronary stenosis

    International Nuclear Information System (INIS)

    Ohtani, Nozomu

    1988-01-01

    We examined the value of digital subtraction angiography (DSA) for the assessment of regional myocardial perfusion by comparing with regional myocardial function in 10 anesthetized dogs. With varying degrees of reduction in left circumflex coronary artery (LCX) blood flow (CBF:categories of stenosis (S1-S5)), myocardial perfusion was assessed by injecting the contrast medium(1ml by power injector) selectively into LCX, and the regional myocardium with contrast was imaged with DSA. We recorded aortic pressure (AOP) and systolic wall thickening (%WTh: sonomicrometry) in the left ventricular posterior wall simultaneously with cine pulse. On the time-density curve obtained from the myocardial regin of interest, we calculated a time interval from the contrast injection to peak concentration (TPC) and exponential washout rate (T). Under varying LCX stenosis, there were no significant change of heart rate and mean AOP and a significant linear correlations were found between %WTh and both 1/TPC(r=0.51)and 1/T(r=0.55). At S1(CBF:100-90% of control), neither %WTh nor 1/TPC differed from control, but 1/T was significantly decreased (80% of contral p<0.01). At S3(CRF:79-60%) to S5(CBF:39-0%), all%WTh, 1/TPC and 1/T were significantly decreased from control (all p<0.01), however, at S5(CBF:39-0%) the value of 1/TPC(71% of control) and 1/T(33%) were not different from that at S4, whereas %WTh was markedly reduced and took place to systolic thinning.. Therefore, in critical coronary stenosis, 1/T was more sensitive than 1/TPC or wall dynamics for assessing myocardial perfusion, however, these indices from DSA had a considerable limitation for evaluating the severity of myocardial ischemia when CBF was markedly reduced. (author)

  9. Morphologic Analysis of Occipital Sinuses for Occipital Screw Fixation Using Digital Subtraction Angiography.

    Science.gov (United States)

    Lee, Dong Hoon; Hong, Jae Taek; Sung, Jae Hoon; Jain, Ashish; Huh, Joon; Kim, Sang Uk; Kim, Joon Young; Kwon, Jae Yoel; Cho, Chul Bum; Kim, Il Sup; Lee, Sang Won

    2016-07-01

    Numerous methods to achieve occipitocervical stabilization have been described, including the use of occipital plate/screw constructs. Bicortical screws may increase the pullout strength, but intracranial injuries to venous sinuses have been reported. This study was performed to analyze the variations in occipital sinuses to prevent sinus injury caused by the bicortical screw. Occipital sinuses of 1720 patients were examined using digital subtraction angiography. The data collected included patient age and sex, occipital sinus type, distance between occipital sinus and midline, depth from inion to occipital sinus, and distance between occipital sinus and midline occiput at different levels. The mean age of patients was 57 years ± 13. There were 807 (46.9%) men and 913 (53.1%) women. The most common occipital sinus type was single occipital sinus off-midline (type B2). The least common occipital sinus type was absent occipital sinuses (type A; 8.7% of patients). There was no significant difference between age and occipital sinus type (P = 0.310). Also, the difference between sexes was not significant in regard to occipital sinus type in general. However, in subgroup analysis of type B1 and B2, there was a significant difference between sexes (P occipital sinus was 19.913 mm ± 7.437. The occipital sinus shows several variations, and many morphologic differences can be seen. Preoperative detailed examination by magnetic resonance venography or vertebral angiography may be required for cases in which bicortical occipital screw fixation is necessary to avoid occipital sinus-related complications. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Comparison of CT angiography and digital subtraction angiography in the evaluation of intracranial aneurysmal neck

    International Nuclear Information System (INIS)

    Kim, Yoo Kyung; Baik, Seung Kug; Shin, Mi Jeong; Choi, Han Yong

    2001-01-01

    To compare the usefulness of three-dimensional multislice CT angiography(CTA) and digital subtraction angiography (DSA) in the evaluation of intracranial aneurysmal neck. Nineteen patients with intracranial aneurysm (23 cases) underwent DSA and subsequent CTA. Using a multislice CT scanner and the SSD(shaded surface display) technique, clipping, cutting and the MPR technique, three-dimensional images were obtained. These were (a) external, (b) internal, from the direction of the parent artery, (c) internal, from the direction of the aneurysmal dome, and (d) an aneurysmal cutting image. The CTA findings were retrospectively compared with the DSA images. Twenty aneurysms were small and three were large. In eleven cases aneurysm neck was small, in nine it was wide, and in three it was relatively wide. For aneurysmal neck evaluation, CTA was superior to DSA in six of nine wide-neck aneurysms and all three large-sized wide-neck aneurysms. In small neck aneurysms 8 of 11 cases and in relatively wide neck all 3 cases showed similarly good images by both modalities. Of the 23 cases demonstrated by four different images, 14 cases showed the best image in internal image from parent artery direction and 6 cases showed similarly good image in both aneurysmal cutting image and internal image from parent artery direction. In the evaluation of wide neck aneurysms, 7 of 9 cases showed the best image at internal image from parent artery direction, compared with other three different images. In two cases of aneurysms, calcification was visible in the aneurysmal wall, so it was difficult to evaluate the aneurysmal neck. CTA was superior to DSA in the evaluating the intracranial aneurysmal neck. CTA maybe an additional available modality to evaluate the aneurysmal neck which is difficult to detect by the DSA. And the information of intracranial aneurysmal neck through CTA will be of value in surgical and endovascular treatment

  11. A 2D driven 3D vessel segmentation algorithm for 3D digital subtraction angiography data

    International Nuclear Information System (INIS)

    Spiegel, M; Hornegger, J; Redel, T; Struffert, T; Doerfler, A

    2011-01-01

    Cerebrovascular disease is among the leading causes of death in western industrial nations. 3D rotational angiography delivers indispensable information on vessel morphology and pathology. Physicians make use of this to analyze vessel geometry in detail, i.e. vessel diameters, location and size of aneurysms, to come up with a clinical decision. 3D segmentation is a crucial step in this pipeline. Although a lot of different methods are available nowadays, all of them lack a method to validate the results for the individual patient. Therefore, we propose a novel 2D digital subtraction angiography (DSA)-driven 3D vessel segmentation and validation framework. 2D DSA projections are clinically considered as gold standard when it comes to measurements of vessel diameter or the neck size of aneurysms. An ellipsoid vessel model is applied to deliver the initial 3D segmentation. To assess the accuracy of the 3D vessel segmentation, its forward projections are iteratively overlaid with the corresponding 2D DSA projections. Local vessel discrepancies are modeled by a global 2D/3D optimization function to adjust the 3D vessel segmentation toward the 2D vessel contours. Our framework has been evaluated on phantom data as well as on ten patient datasets. Three 2D DSA projections from varying viewing angles have been used for each dataset. The novel 2D driven 3D vessel segmentation approach shows superior results against state-of-the-art segmentations like region growing, i.e. an improvement of 7.2% points in precision and 5.8% points for the Dice coefficient. This method opens up future clinical applications requiring the greatest vessel accuracy, e.g. computational fluid dynamic modeling.

  12. Follow-up and Final Results of the Oslo I Study Comparing Screen-Film Mammography and Full-field Digital Mammography with Soft-Copy Reading

    International Nuclear Information System (INIS)

    Skaane, P.; Skjennald, A.; Young, K.

    2005-01-01

    Purpose: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. Material and Methods: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. Results: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P 0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P = 0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A

  13. Follow-up and Final Results of the Oslo I Study Comparing Screen-Film Mammography and Full-field Digital Mammography with Soft-Copy Reading

    Energy Technology Data Exchange (ETDEWEB)

    Skaane, P.; Skjennald, A.; Young, K. [Ullevaal Univ. Hospital, Oslo (Norway). Dept. of Radiology] [and others

    2005-11-01

    Purpose: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. Material and Methods: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. Results: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P 0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P = 0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A

  14. Usefulness of computerized method for lung nodule detection on digital chest radiographs using similar subtraction images from different patients

    International Nuclear Information System (INIS)

    Aoki, Takatoshi; Oda, Nobuhiro; Yamashita, Yoshiko; Yamamoto, Keiji; Korogi, Yukunori

    2012-01-01

    Purpose: The purpose of this study is to evaluate the usefulness of a novel computerized method to select automatically the similar chest radiograph for image subtraction in the patients who have no previous chest radiographs and to assist the radiologists’ interpretation by presenting the “similar subtraction image” from different patients. Materials and methods: Institutional review board approval was obtained, and the requirement for informed patient consent was waived. A large database of approximately 15,000 normal chest radiographs was used for searching similar images of different patients. One hundred images of candidates were selected according to two clinical parameters and similarity of the lung field in the target image. We used the correlation value of chest region in the 100 images for searching the most similar image. The similar subtraction images were obtained by subtracting the similar image selected from the target image. Thirty cases with lung nodules and 30 cases without lung nodules were used for an observer performance test. Four attending radiologists and four radiology residents participated in this observer performance test. Results: The AUC for all radiologists increased significantly from 0.925 to 0.974 with the CAD (P = .004). When the computer output images were available, the average AUC for the residents was more improved (0.960 vs. 0.890) than for the attending radiologists (0.987 vs. 0.960). Conclusion: The novel computerized method for lung nodule detection using similar subtraction images from different patients would be useful to detect lung nodules on digital chest radiographs, especially for less experienced readers.

  15. Comparison of conventional panoramic radiography and panoramic digital subtraction radiography in detection of simulated lesions of mandibular condyle

    Directory of Open Access Journals (Sweden)

    Panjnoush M.

    2008-12-01

    Full Text Available "n  "nBackground and Aim: Digital subtraction Radiography (DSR is a method of accurate assessing condylar head changes. several studies have been carried out in applying DSR in dentistry, however there is a few number of studies in efficacy of DSR method in assesment of condylar head changes, The aim of this study was to compare panoramic radiography and DSR detecting simulated lesions of the mandibular condyl. "nMaterials and Methods: this was a process reaserch study, in which two dry human skulls with no obvious temporomandibular joint pathology were used. Osteophytic lesions were simulated using three sizes of bone chips that were placed on the medial portion of anterior and superolateral aspects of the condyle. Osteolytic lesions were simulated making 1 and 2 mm holes using round burr in the central portion of anterior aspect and Lateral pole of the condyle. Panoramic radiographs were prepared with and without the lesions in place. These paired radiographs were digitized and digital- subtraction images of the original panoramic images were obtained. Eight observers evaluated 155 images of each modality for the presence or absence and the type of simulated lesions of the mandibular condyle. Sensitivity, specificity, reliability and measure of agreement were analyzed using kappa test and crossed tables and qualitative variables were assess by chi-square and fisher's Exact test. "nResults: Specificity of panoramic and DSR methods were 15.4% and 66.7% respectively. Sensitivity of panoramic and DSR methods were 61.1% and 80.6% for osteophytic lesions and 37.5% and 83.3% for Osteolytic lesions. The percentage of correct decisions made in DSR method was significantly more than conventional panoramic method (82.6% vs 41.9% (p<0.0001. "nConclusion: Based on the results of this study digital subtraction technique was significantly more accurate than the panoramic radiographs in detection of simulated lesions of the mandibular condyle.

  16. Three-dimensional image reconstruction using rotational digital subtraction technique: the initial experience of the clinical application

    International Nuclear Information System (INIS)

    Ouyang Zhongnan; Tang Jun; He Jianjun; Lu Xiaohe; Xun Yanping

    2002-01-01

    Objective: To evaluate the benefit of three-dimensional (3D) reconstruction images with rotational digital subtraction technique for the clinical applications. Methods: Conventional two-dimensional digital substraction angiography (2D DSA) was obtained on A-P and lateral view. Three-dimensional digital subtraction angiography (3D DSA) images were obtained by reconstruction of a rotational acquisition on a C-arm (LCV +, GE Medical Systems) spinning at 40 degrees per second. 53 cases of cerebral angiographies were performed (32 men and 21 women; the age ranged from 19 to 72 years, mean 46.3 years). Results: In this series of 53 cases of cerebral angiographies, 5 cases of arteriovenous malformation were all correctly diagnosed by 3D DSA and 2D DSA. Seven cases were misdiagnosed as intracranial aneurysms at conventional 2D DSA but confirmed to be kinking of the vessel by 3D DSA. 41 cases were confirmed to be intracranial aneurysms. Of the 41 cases, 5 cases were diagnosed as normal at 2D DSA but confirmed to be intracranial aneurysms at 3D DSA. The total consistency rate of 3D DSA and 2D DSA for the diagnosis of intracranial aneurysm is 77.4% (41/53). The consistent test shows that there was consistency between the two modalities (chi-square test, χ 2 = 5.267, P < 0.05). 29 cases were treated with endovascular coil embolization. Among them only 3 cases of the aneurysm's neck could be best visualized by 2D DSA but 29 cases by 3D DSA. Conclusion: 3D reconstruction images with rotational digital subtraction technique is a useful tool to study the vascular diseases using less contrast agent and a lower radiation dose and shortening the examination process. It is replenishment for conventional 2D DSA. This technique enables better diagnosis for intracranial vascular lesion and visualization of complex vascular relationships and structures. It is valuable for surgical planning and interventional procedure

  17. In vivo optical imaging of amblyopia: Digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography.

    Science.gov (United States)

    Guo, Lei; Tao, Jun; Xia, Fan; Yang, Zhi; Ma, Xiaoli; Hua, Rui

    2016-09-01

    Amblyopia is a visual impairment that is attributed to either abnormal binocular interactions or visual deprivation. The retina and choroids have been shown to be involved in the development of amblyopia. The purpose of this study was to investigate the retinal and choroidal microstructural abnormalities of amblyopia using digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography (SSADA) approaches. This prospective study included 44 eyes of 22 patients with unilateral amblyopia. All patients who received indirect ophthalmoscopy, combined depth imaging spectral domain optical coherence tomography (OCT), SSADA-OCT, and macular blue light (BL-) and near-infrared (NIR-) autofluorescences underwent pupil dilation. The subfoveal choroidal thickness (SFCT) was measured. BL- and NIR-autofluorescences were determined for all patients and used to generate subtraction images with ImageJ software. The superficial, deep layers of the retina, and inner choroid layer were required for SSADA-OCT. For the normal eyes, a regularly increasing signal was observed in the central macula based on the subtraction images. In contrast, a decreased signal for the central patch or a reduced peak was detected in 16 of 22 amblyopic eyes (72.7%). The mean SFCT of the amblyopic eyes was greater than that of the fellow normal eyes (399.25 ± 4.944 µm vs. 280.58 ± 6.491 µm, respectively, P autofluorescence. The mechanistic relationship of a thicker choroid and choroidal capillary atrophy with amblyopia remains to be described. The digital subtraction image confirmed the changes in the microstructure of the amblyopic retina as a supplementary approach to detect the progression of amblyopia. Lasers Surg. Med. 48:660-667, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Automatic flow analysis of digital subtraction angiography using independent component analysis in patients with carotid stenosis.

    Directory of Open Access Journals (Sweden)

    Han-Jui Lee

    Full Text Available Current time-density curve analysis of digital subtraction angiography (DSA provides intravascular flow information but requires manual vasculature selection. We developed an angiographic marker that represents cerebral perfusion by using automatic independent component analysis.We retrospectively analyzed the data of 44 patients with unilateral carotid stenosis higher than 70% according to North American Symptomatic Carotid Endarterectomy Trial criteria. For all patients, magnetic resonance perfusion (MRP was performed one day before DSA. Fixed contrast injection protocols and DSA acquisition parameters were used before stenting. The cerebral circulation time (CCT was defined as the difference in the time to peak between the parietal vein and cavernous internal carotid artery in a lateral angiogram. Both anterior-posterior and lateral DSA views were processed using independent component analysis, and the capillary angiogram was extracted automatically. The full width at half maximum of the time-density curve in the capillary phase in the anterior-posterior and lateral DSA views was defined as the angiographic mean transient time (aMTT; i.e., aMTTAP and aMTTLat. The correlations between the degree of stenosis, CCT, aMTTAP and aMTTLat, and MRP parameters were evaluated.The degree of stenosis showed no correlation with CCT, aMTTAP, aMTTLat, or any MRP parameter. CCT showed a strong correlation with aMTTAP (r = 0.67 and aMTTLat (r = 0.72. Among the MRP parameters, CCT showed only a moderate correlation with MTT (r = 0.67 and Tmax (r = 0.40. aMTTAP showed a moderate correlation with Tmax (r = 0.42 and a strong correlation with MTT (r = 0.77. aMTTLat also showed similar correlations with Tmax (r = 0.59 and MTT (r = 0.73.Apart from vascular anatomy, aMTT estimates brain parenchyma hemodynamics from DSA and is concordant with MRP. This process is completely automatic and provides immediate measurement of quantitative peritherapeutic brain parenchyma

  19. Simultaneous optical digital half-subtraction and -addition using SOAs and a PPLN waveguide.

    Science.gov (United States)

    McGeehan, John E; Kumar, Saurabh; Willner, Alan E

    2007-04-30

    We demonstrate an optical half-subtracter and half-adder module that performs simultaneous bit-wise subtraction and addition of two 5 Gbit/s RZ data streams. We generate Borrow (/X*Y) and Difference/Sum (X plus sign in circleY, or XOR) outputs using cross-gain modulation (XGM) in two parallel SOAs. Taking advantage of the gain saturation inherent to SOAs, we generate two signals, /X*Y, and X*/Y, and combine them using a passive optical coupler to generate the XOR Difference/Sum output. We use difference-frequency-generation-based lambda-conversion in a PPLN waveguide to generate the Carry (X*Y) output. The PPLN waveguide allows bit-synchronous wavelength shifting, is wide-bandwidth, and offers no intrinsic chirp. Our module uses three active elements to perform simultaneous half-subtraction and addition, and carries a maximum power penalty of 1.0 dB.

  20. Digital subtraction radiographic analysis of the combination of bioabsorbable membrane and bovine morphogenetic protein pool in human periodontal infrabony defects

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Machado Guimarães

    2010-08-01

    Full Text Available OBJECTIVES: This study assessed the bone density gain and its relationship with the periodontal clinical parameters in a case series of a regenerative therapy procedure. MATERIAL AND METHODS: Using a split-mouth study design, 10 pairs of infrabony defects from 15 patients were treated with a pool of bovine bone morphogenetic proteins associated with collagen membrane (test sites or collagen membrane only (control sites. The periodontal healing was clinically and radiographically monitored for six months. Standardized pre-surgical and 6-month postoperative radiographs were digitized for digital subtraction analysis, which showed relative bone density gain in both groups of 0.034 ± 0.423 and 0.105 ± 0.423 in the test and control group, respectively (p>0.05. RESULTS: As regards the area size of bone density change, the influence of the therapy was detected in 2.5 mm² in the test group and 2 mm² in the control group (p>0.05. Additionally, no correlation was observed between the favorable clinical results and the bone density gain measured by digital subtraction radiography (p>0.05. CONCLUSIONS: The findings of this study suggest that the clinical benefit of the regenerative therapy observed did not come with significant bone density gains. Long-term evaluation may lead to a different conclusions.

  1. Digital subtraction ventriculography for assessment of global and regional leftventricular parameters in comparison to conventional contrast ventriculography

    International Nuclear Information System (INIS)

    Eichstaedt, H.; Langer, M.; Felix, R.

    1984-01-01

    Since May 1982 we studied more than 100 patients with heart diseases by means of digital angiography, out of them 46 patients with a history of transmural myocardial infarction were selected. Urografin 76, 30 ml, was administered at a flow rate of 18 ml/s by means of a catheter in the superior vena cava during digital subtraction ventriculography. Results were compared with conventional contrast ventriculograms. The correlation coefficient was r=0.93 (p 0.001) for determination of ejection fraction with both methods. The data in individual cases suggest that DSV is more sensitive than conventional contrast ventriculography in determination of severely reduced ejection fractions. The methods are practically identical in qualitative evaluation of disorders of regional wall motion in the anterolateral region, while DSV is more sensitive than conventional ventriculography in evaluating the apical region. Sensitivity was 85.7% when the two methods were compared in evaluation of the inferior region of the left ventricle. Both methods are identical in demonstration of severely deformed ventricles. Digital subtraction ventriculography may replace conventional contrast ventriculography in some of situations discussed above. (orig.)

  2. Gadolinium-enhanced MR angiography of arterial occlusive disease in lower extremity : comparison with conventional digital subtraction angiography

    International Nuclear Information System (INIS)

    Shin, Sang June; Koh, Young Hwan; Cha, Joo Hee; Kim, Hyu Beom; Chung, Jin Wook; Park, Jae Hyung

    2000-01-01

    To compare the diagnostic value of gadolinium-enhanced MR angiography with that of conventional digital subtraction angiography for the evaluation of lower extremity arterial occlusive diseases. In 26 patients with symptomatic lower extremity arterial occlusive disease, both conventional digital subtraction angiography (DSA) and gadolinium-enhanced MR angiography (CE-MRA) were performed during the same week. MR angiography was performed using three-dimensional gradient-echo acquisition before, and two sequential acquisitions after, the administration of gadolinium (0.2 mmol/kg). In 23 patients, two separate, contiguous areas were scanned using additional doses. In three patients, only one field with a suspicious lesion was scanned. Three radiologists independently analyzed the CE-MRA and DSA findings of each vascular segment (20 segments per arterial tree) for the presence of obstructive lesions; the grade assigned was either mild or none (less than 50%), stenotic (50%-99%), or occlusion (100%). From among a total of 462 segments, DSA detected 99 which were significantly narrowed (stenosis, 33; occlusion, 66). Using MR angiography, 102 segments (stenosis 39; occlusion, 63) were identified, and 94 lesions (stenosis, 32; occlusion, 62) were graded correctly. Seven lesions were overestimated and four were underestimated. For the detection of hemodynamically significant stenosis or occlusions using MR angiography, sensitivity, specificity, and diagnostic accuracy were 95%, 98%, and 98% (G=3D0.995, P less than 0.001), respectively. To prove the absence of lesions, we repeated DSA in two patients with arterial spasm due to puncture. Three occluded segments seen on DSA, which revealed intact segments on MR angiography, suggested slow distal flow after reconstitution. For the evaluation of lower extremity arterial occlusive disease, the diagnostic value of gadolinium-enhanced MR angiography is comparable with that of digital subtraction angiography. The advantages of the

  3. Comparison of spiral CT angiography with conventional digital subtraction angiography in the evaluation of renal transplant donors: a pilot study

    International Nuclear Information System (INIS)

    Chu, C.; Young, N.; Lau, H.

    2001-01-01

    Conventional digital subtraction renal arteriography (IA-DSA) has been traditionally used as the preoperative imaging modality for assessment of renal vascular anatomy for renal transplant donors. This study evaluates the potential use of spiral CT angiography in replacing IA-DSA in the preoperative assessment of this group of patients. Seven patients underwent both spiral CT angiography and IA-DSA between October 1997 and April 1998. It is concluded that spiral CT angiography can demonstrate the number, length and location of renal arteries and it is suggested that spiral CT angiography can potentially replace IA-DSA in the preoperative assessment of renal donors. Copyright (2001) Blackwell Science Pty Ltd

  4. Visualization of the renal venous system by renal arteriography with digital subtraction angiography

    International Nuclear Information System (INIS)

    Nagai, Jun

    1989-01-01

    The purpose of this study was to obtain vivid and precise images of intrarenal venous branching using DSA for renal arteriography. The type of system used was an ADAC DPS-4100C with 70-80 kVp, and 320 mA, 25-50 msec at 6 frames/sec. The duration was 10 sec and the matrix size was 512x512. In order to retain clear subtracted images of intrarenal venous branching with minimal noise the three frames were selected on the time-density curve of DSA: (Fig.3). 1) a frame on which renal arteries disappear (frame X), 2) the frame with highest renal venous density value as (frame Y), 3) the difference of the nephrogram density between X and Y frames in which only the density of the nephrogram decreases (frame Z). The mask image is the image subtracted by the equation of the weighted averaging method on X and Z frame and is subtracted from the image of Y frame in the final step. By this method, 40 kidneys in 36 patients were studied, and the intrarenal venous branches up to the interlobar vein was clearly demonstrated in 28 of these cases (70%). This method is useful to estimate the extent of intrarenal lesions and detect abnormal renal blood flow compared with conventional temporal subtraction method. (author)

  5. [X-ray semiotics of sialolithiasis in functional digital subtraction sialography].

    Science.gov (United States)

    Iudin, L A; Kondrashin, S A; Afanas'ev, V V; Shchipskiĭ, A V

    1995-01-01

    Twenty-seven patients with sialolithiasis were examined using functional subtraction sialography developed by the authors. Differential diagnostic signs characterizing the degree of involvement of the salivary gland were defined. High efficacy of the method helps correctly plan the treatment strategy.

  6. Self-masking noise subtraction (SMNS) in digital X-ray tomosynthesis for the improvement of tomographic image quality

    International Nuclear Information System (INIS)

    Oh, J.E.; Cho, H.S.; Choi, S.I.; Park, Y.O.; Lee, M.S.; Cho, H.M.; Yang, Y.J.; Je, U.K.; Woo, T.H.; Lee, H.K.

    2011-01-01

    In this paper, we proposed a simple and effective reconstruction algorithm, the so-called self-masking noise subtraction (SMNS), in digital X-ray tomosynthesis to reduce the tomographic blur that is inherent in the conventional tomosynthesis based upon the shift-and-add (SAA) method. Using the SAA and the SMNS algorithms, we investigated the influence of tomographic parameters such as tomographic angle (θ) and angle step (Δθ) on the image quality, measuring the signal-difference-to-noise ratio (SDNR). Our simulation results show that the proposed algorithm seems to be efficient in reducing the tomographic blur and, thus, improving image sharpness. We expect the simulation results to be useful for the optimal design of a digital X-ray tomosynthesis system for our ongoing application of nondestructive testing (NDT).

  7. Safety of Diagnostic Cerebral and Spinal Digital Subtraction Angiography in a Developing Country: A Single-Center Experience.

    Science.gov (United States)

    Bashir, Qasim; Ishfaq, Asim; Baig, Ammad Anwar

    2018-02-01

    Digital subtraction angiography (DSA) remains the gold standard imaging modality for cerebrovascular disorders. In contrast to developed countries, the safety of the procedure is not extensively reported from the developing countries. Herein, we present a retrospective analysis of the basic technique, indications, and outcomes in 286 patients undergoing diagnostic cerebral and spinal angiography in a developing country, Pakistan. A retrospective review of patient demographics, procedural technique and complication rates of 286 consecutive patients undergoing the diagnostic cerebral/spinal angiography procedure at one institution from May 2013 to December 2015 was performed. Neurological, systemic, or local complications occurring within and after 24 h of the procedure were recorded. Mean age reported for all patients was 49.7 years. Of all the 286 cases, 175 were male (61.2%) and the rest female (111, 38.8%). Cerebral DSA was performed in 279 cases (97.6%), with 7 cases of spinal DSA (2.4%). Subarachnoid hemorrhage was the most common indication for DSA accounting for 88 cases (30.8%), closely followed by stroke (26.6%) and arteriosclerotic vascular disease (23.1%). No intra- or post-procedural neurological complications of any severity were seen in any of the 286 cases. One case of asymptomatic aortic dissection was reported (0.3%) in the entire cohort of patient population. Diagnostic cerebral/spinal digital subtraction angiography was found to be safe in Pakistan, with complication rates at par with and comparable to those reported in the developed world.

  8. 15-Year Follow-Up

    OpenAIRE

    Karjula, Salla; Morin-Papunen, Laure; Auvinen, Juha; Ruokonen, Aimo; Puukka, Katri; Franks, Stephen; Jarvelin, Marjo-Riitta; Tapanainen, Juha S.; Jokelainen, Jari; Miettunen, Jouko; Piltonen, Terhi T.

    2017-01-01

    Context: Polycystic ovary syndrome (PCOS) is associated with increased psychological distress, obesity and hyperandrogenism being suggested as key promoters. Objectives: To investigate the prevalence of anxiety/depression and their coexistence in women with PCOS/PCOS-related symptoms at ages 31 and 46. The roles of obesity, hyperandrogenism, and awareness of PCOS on psychological distress were also assessed. Design: Population-based follow-up. Setting: Northern Finland Birth Cohort 1966 with ...

  9. Clinical and radiological of acute ischemic stroke patients without angiographic occlusion on digital subtraction angiogram. A pooled analysis of case series

    International Nuclear Information System (INIS)

    Shah, Qaisar A.; Memon Zeeshan, Muhammad; Vazquez, Gabriela; Suri, M. Fareed K.; Hussein, Haitham M.; Qureshi, Adnan I.; Mohammad, Yousef M.

    2008-01-01

    Approximately 20-30% of the patients with acute ischemic stroke do not have any occlusion demonstrated on initial digital subtraction angiography (DSA). We sought to determine the risk and rates of cerebral infarction and favorable neurological outcome in this group of acute ischemic stroke patients. Patients were identified from a prospectively maintained stroke database and from literature search of MEDLINE, PubMed, and Cochrane databases. All patients had initial neurological assessment on National Institutes of Health Stroke Scale (NIHSS). Patients then underwent DSA after initial head computed tomography (CT) scans. Follow-up radiological assessment at 24-72 h was performed with CT and magnetic resonance imaging scans. Association of stroke risk factors with clinical and radiological outcomes was estimated. A total of 81 patients was analyzed (mean age 63 years; 28 were women). The median NIHSS score was 8 (range 2-25). None of the patients received either intravenous or intra-arterial thrombolytic. Cerebral infarction was detected in 62 (76%) of the 81 patients. Twenty-four to 48-h NIHSS was available for 51 patients only. Neurological improvement was observed in 22 (43%) of the 51 patients. Favorable outcome ascertained at 3-month follow-up was seen in 48 (59%) of the 81 patients. After adjusting for age, sex, and baseline NIHSS, male patients [odds ratio (OR) 4.5 (1.4-14.3), p value=0.01] and patients with age≥ =65 [OR 4.3 (1.2-16.2), p value=0.03] have a higher risk of cerebral infarcts on the follow-up imaging. Similarly, patients who presented with 10 NIHSS [OR 0.21 (0.08-0.61), p value=0.004]. Ischemic stroke patients without arterial occlusion on DSA have a higher risk of cerebral infarction and disability particularly in men, patients over 65 years of age and with NIHSS≥=10. The cause of infarction may have been arterial obstruction with spontaneous recanalization or small vessel occlusion not visible on DSA

  10. Methods and time schedule for follow-up of intracranial aneurysms treated with endovascular embolization: a systematic review.

    Science.gov (United States)

    Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

    2011-01-01

    To review the diagnostic value of angiographic methods and the optimal timetable for follow-up imaging of patients after endovascular treatment of intracranial aneurysms. A comprehensive computer-aided search for relevant primary papers was performed using the MEDLINE, PubMed, Embase, and Cochrane Collaboration database from January 1991 to March 2011. Original papers were included that reported either diagnostic value of angiographic modalities for follow-up vs. digital subtracted angiography (DSA) or comparison of aneurysm occlusion rate in delayed vs. early follow-up. The systematic review identified 35 relevant studies: 3 on the diagnostic value of three-dimensional (3D) DSA, 30 on the performance of magnetic resonance angiography (MRA), and 3 on time schedules for follow-up. 3D DSA had sensitivity of 100%, and specificity of 58.3-94.7%. Magnetic resonance angiography had sensitivity of 28.4-100%, and specificity of 50.0-100%. The proportion of aneurysms that recanalized between the early follow-up examination at 6 months and the delayed imaging at 1.5-6.0 years was 0-2.5%. Magnetic resonance angiography seems to be the best imaging method for the follow-up. In selected cases, when invasive angiography is necessary, 3D DSA should be considered to improve the diagnostic accuracy. Most patients who present with stable and adequate aneurysm occlusion at 6 months after coiling may not require further follow-up. Key words: intracranial aneurysm, embolization, coils, digital subtracted angiography, magnetic resonance, computed tomography.

  11. Pulmonary arteriography by digital subtraction angiographic method in cyanotic heart disease with pulmonary stenosis or pulmonary atresia

    International Nuclear Information System (INIS)

    Kobayashi, Junjiro; Hirose, Hajime; Nakano, Susumu

    1985-01-01

    Pulmonary arteriography was performed by digital subtraction angiographic (DSA) method in 10 patients with cyanotic heart disease associated with pulmonary stenosis or pulmonary atresia. Ten patients consisted of five patients with tetralogy of Fallot, three with single ventricle and pulmonary stenosis, and two with pseudotruncus arteriosus. Hepato-clavicular position was taken in four patients. Pulmonary artery and its main branches were opacified and recognized clearly, and their diameter could be measured accurately with a small amount of contrast medium. There was a good correlation between the diameter of pulmonary artery measured by DSA and that measured by conventional pulmonary arteriography. DSA is a useful method for evaluating the size and the stenosis of pulmonary artery especially in small cyanotic infants. (author)

  12. Comparison between digital subtraction angiography and magnetic resonance angiography in investigation of nonlacunar ischemic stroke in young patients: preliminary results.

    Science.gov (United States)

    Conforto, Adriana Bastos; Fregni, Felipe; Puglia, Paulo; Leite, Claudia da Costa; Yamamoto, Fabio Iuji; Coracini, Karen F; Scaff, Milberto

    2006-06-01

    We preliminarily investigated the relevance of performing digital subtraction angiography (DSA) in addition to magnetic resonance angiography (MRA) in definition of ischemic stroke etiology in young patients. DSAs and MRAs from 17 young patients with nonlacunar ischemic stroke were blindly analyzed and their impact on stroke management was evaluated. Etiologies were the same considering results of either DSA or MRA in 12/17 cases. In 15/17 patients no changes would have been made in treatment, regardless of the modality of angiography considered. These preliminary results suggest that DSA may be redundant in two thirds of ischemic strokes in young patients. Further larger prospective studies are necessary to determine indications of DSA in this age group.

  13. Middle and long-term follow-up of intracranial aneurysms treated with Matrix detachable coils

    International Nuclear Information System (INIS)

    Wu Xi; Liu Jianmin; Huang Qinghai; Xu Yi

    2008-01-01

    Objective: This study was undertaken to evaluate the safety of the polyglycolic/polylactic acid (PGLA)-coated Matrix detachable coils (Matrix) and analyze factors which may relate to the recanalization rate of the Matrix coils in the treatment of intracranial aneurysms. Methods: 75 patients underwent 79 aneurysm treatments with Matrix coils from May 2003 to July 2005 were retrospectively investigated. Morphological changes were compared postoperatively with last-follow-up digital subtraction angiography (DSA) by using the Raymond scale. We defined incomplete recanalization or stable aneurysms as uncured, while those of progressive occlusion or complete occlusion aneurysms demonstrated on the last-follow-up imagings as cured. We also utilized Cox model for analyzing the relationships between factors including age, gender, degree of aneurysmal occlusion, stenting, aneurysm neck size, aneurysm maximum size and Matrix coils length (%) and the long-term angiographic follow-up results. Results: The correlative surgical complications rate with Matrix coils was 13.3%. The total rate of recanalization was 11.4%. Large aneurysms treated with combined stenting got 40% recanalization. No statistic relationships were shown between the factors forementioned and the recanalization rate, but progressive occlusion was observed in 11 (61%)incompletely treated aneurysms. Conclusions: Matrix detachable coil technique is safe for intracranial aneurysm and would further decrease the recurrence of large aneurysm with combination of stenting but long term efficacy needs further follow-up and large scale randomized control study. (authors)

  14. Influence of homeopathic treatment with comfrey on bone density around titanium implants: a digital subtraction radiography study in rats.

    Science.gov (United States)

    Sakakura, Celso Eduardo; Neto, Rubens Spin; Bellucci, Marina; Wenzel, Ann; Scaf, Gulnara; Marcantonio, Elcio

    2008-06-01

    The objective of this study was to evaluate the influence of homeopathic treatment with comfrey (Shymphytum officinalis 6CH) on radiographic bone density and area around titanium implants. Forty-eight rats were divided into two groups of 24 animals each: a control group (C) and a test group (SO). Each animal received one titanium micro-implant placed in the tibia. The animals in Group SO were subjected to 10 drops of comfrey 6CH per day mixed into their drinking water until the day of sacrifice. Eight animals of each group were sacrificed at 7, 14 and 28 days post-surgery, respectively. Standardized digital radiographs were obtained on the day of implant installation (baseline images) and on the day of sacrifice (final images). Digital subtraction of the two corresponding images was performed to evaluate changes in bone density and the area related to change around the implant between baseline and final images. Subtraction images demonstrated that a significant difference existed in mean shade of gray at 14 days post-surgery between Group SO (mean 175.3+/-14.4) and Group C (mean 146.2+/-5.2). Regarding the area in pixels corresponding to the bone gain in Group SO, the differences observed between the sacrifice periods and groups were only significant at 7 days sacrifice between Group SO (mean 171.2+/-21.9) and Group C (mean 64.5+/-60.4). Within the limits of this study, comfrey administration promotes an increase in radiographic bone density around titanium implants in the initial period of bone healing.

  15. Temporal Subtraction of Digital Breast Tomosynthesis Images for Improved Mass Detection

    National Research Council Canada - National Science Library

    Li, Christina M

    2007-01-01

    Digital breast tomosynthesis (DBT) strives to overcome the obstacles presented in conventional 2D mammography by taking multiple projections over a fixed angle and reconstructing volumetric data isolates overlying anatomy...

  16. Determination of the functional significance of coronary artery disease with digital subtraction angiography

    International Nuclear Information System (INIS)

    Mancini, G.B.J.; Hodgson, J.McB.; Le Grand, V.; Vogel, R.A.; Le Free, M.T.; Bates, E.R.; Aueron, F.M.

    1986-01-01

    Imaging of the chambers of the heart, pulmonary circulation and great vessels by intravenous contrast injection was clinically implemented in 1939, but intensive interest in this technique was not generated until relatively recent advances in digital electronics, image intensification, and television technology. Pioneering work from several centers initiated a widespread clinical evaluation of this imaging modality in cardiac diagnosis that was facilitated by commercially available digital angiography systems that provided rudimentary image manipulation techniques. Such image manipulation was also of considerable use in intraarterial applications. The quantitative information inherent in digital images of the heart chambers and coronary arteries sparked a keen interest in using this technology to extract both anatomical and physiological information about patients undergoing cardiac catheterization. This chapter outlines their approach to the use of both intravenous and intraarterial digital techniques in the evaluation of patients requiring cardiac catheterization with a particular emphasis on determination of the functional significance of coronary disease

  17. The analysis of cerebro-vascular circulation time using digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Han, D. G.; Kim, D. H.; Lee, H. K.; Kwon, K. H.; Kim, K. J.

    1986-01-01

    We analyzed the cerebral arterio-venous circulation time of 141 cases of cranial DSA in 136 patients, for the assessment of cerebral circulatory dynamics. IV-DSA was 111 cases, IA-DSA 30 cases. The results were as follows: 1. There was no significant difference in arterio-venous circulation time between IA-DSA and IV-DSA, if the disease pattern was not considered (P > 0.1). 2. Prolongation of arterio-venous circulation time was noted in the cases of cerebral (cerebellar) hemorrhage, subarachnoid hemorrhage, intracranial hematoma, brain abscess, acute stage of cerebra-vascular occlusive disease, acute stage of postoperative follow up, and acute stage of cerebral contusion (p > 0.05). 3. Compared the chronic stage of cerebra-vascular occlusive disease, postoperative follow up, and cerebral contusion with acute stage, significant decrement of arterio-venous circulation time was resulted (p > 0.05). 4. DSA was a useful modality for the assessment of circulatory dynamics, including measurement of arterio-venous circulation time.

  18. Diagnostic yield and accuracy of CT angiography, MR angiography, and digital subtraction angiography for detection of macrovascular causes of intracerebral haemorrhage: Prospective, multicentre cohort study

    NARCIS (Netherlands)

    C.J.J. Van Asch (Charlotte J.J.); B.K. Velthuis (Birgitta K.); G.J.E. Rinkel (Gabriël J.E.); A. Algra (Ale); G.A.P. de Kort (G. A P); T.D. Witkamp (Theo); J.C.M. De Ridder (Johanna C.M.); K.M. Van Nieuwenhuizen (Koen M.); F.-E. De Leeuw (Frank-Erik); W.J. Schonewille (Wouter); P.L.M. de Kort (Paul); D.W.J. Dippel (Diederik); T.W.M. Raaymakers (Theodora W.M.); J. Hofmeijer; M.J.H. Wermer (Marieke); H. Kerkhoff (Henk); K. Jellema (Korné); I.M. Bronner (Irene M.); M.J.M. Remmers (Michel ); H.P. Bienfait (Henri); R.J.G.M. Witjes (Ron J.G.M.); J.P. Greving (Jacoba); C.J.M. Klijn (Catharina J.M.); H.F. de Leeuw (Frank); H.B. Boogaarts; E.J. van Dijk (Ewoud); W.J. Schonewille; W.M.J. Pellikaan; C. Puppels-De Waard; P.L.M. De Kort; J.P. Peluso; J. van Tuijl (Jordie); J. Hofmeijer; F.B.M. Joosten (Frank); D.W.J. Dippel (Diederik); L. Khajeh (Ladbon); T.W.M. Raaijmakers; M.J. Wermer; M.A.A. van Walderveen (Marianne); H. Kerkhoff; E. Zock; K. Jellema (Korné); G.J. Lycklama à Nijeholt (Geert); I.M. Bronner; M.J.M. Remmers; R.J.G.M. Witjes; H.P. Bienfait; K.E. Droogh-Greve; R. Donders (Rogier); V.I.H. Kwa; T.H.C.M.L. Schreuder (Tobien H. C. M. L.); C.L. Franke (Cees); J.S. Straver; C. Jansen; S.L.M. Bakker (Stef); C.C. Pleiter (C.); M.C. Visser; C.J.J. Van Asch; B.K. Velthuis (Birgitta); G.J.E. Rinkel (Gabriel); K.M. Van Nieuwenhuizen; C.J.M. Klijn (Catharina J.M.)

    2015-01-01

    textabstractStudy question What are the diagnostic yield and accuracy of early computed tomography (CT) angiography followed by magnetic resonance imaging/angiography (MRI/MRA) and digital subtraction angiography (DSA) in patients with non-traumatic intracerebral haemorrhage? Methods This

  19. Inter- and intra-rater agreement in the assessment of the vascularity of spinal metastases using digital subtraction angiography tumor blush

    DEFF Research Database (Denmark)

    Clausen, Caroline; Dahl, Benny; Frevert, Susanne Christiansen

    2017-01-01

    Background: Preoperative embolization is based on the preoperative digital subtraction angiography (DSA) tumor blush, and as such is considered the “gold standard” for determining tumor vascularity. However, to our knowledge reliability studies evaluating vascularity ratings of DSA tumor blush...

  20. A feasibility study of projection-based energy weighting based on a photon-counting detector in contrast-enhanced digital subtraction mammography: a simulation study

    International Nuclear Information System (INIS)

    Choi, Sunghoon; Lee, Seungwan; Choi, Yuna; Kim, Heejoung

    2014-01-01

    Contrast media, such as iodine and gadolinium, are generally used in digital subtraction mammography to enhance the contrast between target and background materials. In digital subtraction mammography, where one image (with contrast medium) is subtracted from another (anatomical background) to facilitate visualization of the tumor structure, tumors can be more easily distinguished after the injection of a contrast medium. In order to have more an effective method to increase the contrast-to-noise ratio (CNR), we applied a projection-based energy-weighting method. The purpose of this study is to demonstrate the feasibility of using the projection-based energy-weighting method in digital subtraction mammography. Unlike some other previous studies, we applied the projection-based energy-weighting method to more practical mammography conditions by using the Monte Carlo method to simulate four different iodine solutions embedded in a breast phantom comprised of 50% adipose and 50% glandular tissues. We also considered an optimal tube voltage and anode/filter combination in digital iodine contrast media mammography in order to maximize the figure-of-merit (FOM). The simulated source energy was from 20 to 45 keV to prevent electronic noise and include the k-edge energy of iodine (33.2 keV). The results showed that the projection-based energy-weighting improved the CNR by factors of 1.05 - 1.86 compared to the conventionally integrated images. Consequently, the CNR of digital subtraction mammography images can be improved by using projection-based energy-weighting with photon-counting detectors.

  1. A feasibility study of projection-based energy weighting based on a photon-counting detector in contrast-enhanced digital subtraction mammography: a simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sunghoon; Lee, Seungwan; Choi, Yuna; Kim, Heejoung [Yonsei University, Wonju (Korea, Republic of)

    2014-06-15

    Contrast media, such as iodine and gadolinium, are generally used in digital subtraction mammography to enhance the contrast between target and background materials. In digital subtraction mammography, where one image (with contrast medium) is subtracted from another (anatomical background) to facilitate visualization of the tumor structure, tumors can be more easily distinguished after the injection of a contrast medium. In order to have more an effective method to increase the contrast-to-noise ratio (CNR), we applied a projection-based energy-weighting method. The purpose of this study is to demonstrate the feasibility of using the projection-based energy-weighting method in digital subtraction mammography. Unlike some other previous studies, we applied the projection-based energy-weighting method to more practical mammography conditions by using the Monte Carlo method to simulate four different iodine solutions embedded in a breast phantom comprised of 50% adipose and 50% glandular tissues. We also considered an optimal tube voltage and anode/filter combination in digital iodine contrast media mammography in order to maximize the figure-of-merit (FOM). The simulated source energy was from 20 to 45 keV to prevent electronic noise and include the k-edge energy of iodine (33.2 keV). The results showed that the projection-based energy-weighting improved the CNR by factors of 1.05 - 1.86 compared to the conventionally integrated images. Consequently, the CNR of digital subtraction mammography images can be improved by using projection-based energy-weighting with photon-counting detectors.

  2. A quantitative study of bone repair after endodontic therapy on digital subtraction radiography

    International Nuclear Information System (INIS)

    Kim, Jae Duk

    1997-01-01

    This study was performed to prepare the quantitative method of judging the sensitive prognosis of chronic apical periodontitis as early as possible. The subjects were 25 cases with periapical radiolucencies of which were treated with endodontic treatment. Serial radiographs were taken by standardized method longitudinally. The density slice function of digital radiographic system were employed for quantitative and longitudinal assessment of the radiolucent area and the condensing osteitis simultaneously. Obtained results were as follows: 1. The amount of bone repair after endodontic treatment could be detected quantitatively by the density slice function of digital radiographic system. 2. Within the 6-week period after root canal filling, the prognosis could be evaluated by assessment both radiolucent area and condensing osteitis on digital radiographic system. 3. The pattern of bone repair showed peripheral type in most cases from the 6th week after root canal filling. 4. In longitudinal change, bone repair showed two patterns; the succeeding reduction of radiolucent area showing the increase of condensing osteitis in size till 6th week and following by static state or reduction tendency and the reduction following the initial increase of both areas. 5. Cases with pulpitis by trauma showed initial increase of condensing osteitis at 2nd week, marked reduction of radiolucent area and condensing osteitis at 6th week, and approximately normal bone state at 8th week after root canal filling.

  3. A quantitative study of bone repair after endodontic therapy on digital subtraction radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Duk [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Chosun University, Kwangju (Korea, Republic of)

    1997-08-15

    This study was performed to prepare the quantitative method of judging the sensitive prognosis of chronic apical periodontitis as early as possible. The subjects were 25 cases with periapical radiolucencies of which were treated with endodontic treatment. Serial radiographs were taken by standardized method longitudinally. The density slice function of digital radiographic system were employed for quantitative and longitudinal assessment of the radiolucent area and the condensing osteitis simultaneously. Obtained results were as follows: 1. The amount of bone repair after endodontic treatment could be detected quantitatively by the density slice function of digital radiographic system. 2. Within the 6-week period after root canal filling, the prognosis could be evaluated by assessment both radiolucent area and condensing osteitis on digital radiographic system. 3. The pattern of bone repair showed peripheral type in most cases from the 6th week after root canal filling. 4. In longitudinal change, bone repair showed two patterns; the succeeding reduction of radiolucent area showing the increase of condensing osteitis in size till 6th week and following by static state or reduction tendency and the reduction following the initial increase of both areas. 5. Cases with pulpitis by trauma showed initial increase of condensing osteitis at 2nd week, marked reduction of radiolucent area and condensing osteitis at 6th week, and approximately normal bone state at 8th week after root canal filling.

  4. Application of MR digital subtraction angiography to the diagnosis of cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Katase, Shichiro; Tsuchiya, Kazuhiro; Osawa, Ayako; Hachiya, Junichi

    2000-01-01

    We evaluated the utility of MR DSA using rapid thick-section T1-weighted imaging and bolus injections of gadolinium to diagnose cerebral arteriovenous malformations (AVMs). We reviewed MR DSA images obtained from 16 patients (9 men and 7 women; average age, 35.8 years). Anatomic depictions of each component of the AVMs were rated using a four-point grade scale and compared with conventional and/or MR angiograms. We were able to obtain serial images demonstrating passage of gadolinium through the AVM. The average scores for feeders, nidus, and drainers was 1.4, 2.2, and 1.8, respectively with the overall average of 2.1. The MR DSA technique that we have developed presently has limited value in depicting the anatomic details of cerebral AVMs. However, we believe that MR DSA is valuable and should be used in addition to conventional MR imaging and angiography in patients with cerebral AVM at the time of their initial diagnosis and during follow-up after therapy. (author)

  5. Automatic segmentation of coronary vessels from digital subtracted angiograms: a knowledge-based approach

    International Nuclear Information System (INIS)

    Stansfield, S.A.

    1986-01-01

    This paper presents a rule-based expert system for identifying and isolating coronary vessels in digital angiograms. The system is written in OPS5 and LISP and uses low level processors written in C. The system embodies both stages of the vision hierarchy: The low level image processing stage works concurrently with edges (or lines) and regions to segment the input image. Its knowledge is that of segmentation, grouping, and shape analysis. The high level stage then uses its knowledge of cardiac anatomy and physiology to interpret the result and to eliminate those structures not desired in the output. (Auth.)

  6. Radiological investigation of renovascular hypertension from IVU to digital subtraction angiography. A critical evaluation

    International Nuclear Information System (INIS)

    Amiel, M.; Froment, A.; Pinet, F.; Huguet, M.

    1986-01-01

    For the last 20 years, the value of radiology in renovascular hypertension (RVH) is well established from diagnostic and therapeutic points of view. However things are changing now due to a better appraisal of the incidence of RVH, new antihypertensive drugs, and new radiological procedures (digital angiography, percutaneous transluminal angioplasty). The approach now takes in account the mode of imaging for a better evaluation of the renal artery stenosis and costs of the proceedings as well. Finally a new strategy has been set up for RVH patients management [fr

  7. Evaluation of the pedal artery: comparison of three-dimensional gadolinium-enhanced MR angiography with digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Min; Kang, Sung Gwon; Byun, Joo Nam; Kim, Young Cheol; Choi, Jeong Yeol; Kim, Dong Hyun [College of Medicine, Chosun Univ., Kwangju (Korea, Republic of)

    2002-07-01

    To compare the three-dimensional gadolinium-enhanced MR angiography with digital subtraction angiography (DSA) for evaluation of the pedal artery. In 12 extremities of 11 patients, both digital subtraction angiography (DSA) and contrast-enhanced MR angiography (CE-MR angiography) were performed during the same week. Among ten of the 11 patients, the following conditions were present: atherosclerosis (n=4), diabetic foot (n=3), Buerger's disease (n=1), calciphylactic arteriopathy (n=1) and arteriovenous malformation of the foot (n=1). The remaining patient underwent angiography prior to flap surgery. For MR angiography, a 1.5T system using an extremity or head coil was used. A three-dimensional FISP (fast imaging with steady state precession) sequence was obtained before enhancement, followed by four sequential acquisitions (scan time, 20 secs, scan interval time, 10 secs) 10 seconds after intravenous bolus injection of normal saline (total 10 cc), following intravenous administration of gadolinium (0.02 mmol/kg, 3 ml/sec). Arterial segments of the ankle and foot were classified as the anterior or posterior tibial artery, the distal peroneal artery, the medial or lateral plantar artery, the pedal arch, and the dorsalis pedis artery. Two radiologists independently analysed visualization of each arteraial segment and the mean of visible arterial segments in one extreminty using CE-MR angiography and DSA. Among 84 arterial segments, 16 were invisible at both CE-MR angiography and DSA, while 39 were demonstrated by both modalities. Twenty-six segments were visible only at CE-MR angiography and three only at DSA. CE-MR angiography displayed a higher number of arterial segments than DSA (mean, 5.42 vs. mean 3.50, respectively), a difference which was statistically significant (p<0.000). The difference between each arterial segment was not statistically significant, except for the dorsalis pedis artery (t test, p<0.000). In that it provides additional information for

  8. Subtractive Leadership

    Science.gov (United States)

    Larwin, K. H.; Thomas, Eugene M.; Larwin, David A.

    2015-01-01

    This paper introduces a new term and concept to the leadership discourse: Subtractive Leadership. As an extension of the distributive leadership model, the notion of subtractive leadership refers to a leadership style that detracts from organizational culture and productivity. Subtractive leadership fails to embrace and balance the characteristics…

  9. Intravenous digital subtraction angiography for the evaluation of renal artery blood flow following the removal of a neuroblastoma

    International Nuclear Information System (INIS)

    Yamagiwa, Iwao; Obata, Kazuya; Saito, Hiroyuki; Washio, Masahiko

    1994-01-01

    There have been several reports of acute renal failure following the resection of an abdominal neuroblastoma combined with ipsilateral nephrectomy as well as the atrophy or disappearance of an unresected kidney after tumor resection. Spasms or thrombosis of the renal artery during tumor excision are considered to be the major cause. Since 1989, intravenous digital subtraction angiography (IVDSA) has been used to evaluate the renal artery blood flow immediately following surgery in seven patients with abdominal neuroblastomas. IVDSA was performed using a central venous catheter inserted prior to surgery. In all seven patients, IVDSA provided clear images for the evaluation of renal artery blood flow. In one of the two patients whose kidneys briefly became cyanosed during tumor excision, IVDSA demonstrated an occlusion of the renal artery and prompt measures could be taken to reestablish the blood flow. No complications of IVDSA occurred in any of the seven patients. IVDSA using a central venous catheter was thus considered to be useful for evaluating the renal artery blood flow in patients with a suspected renal artery blood flow disturbance without any risk of complications, and this modality obviated the need for intraarterial angiography. (author)

  10. Multislice CT Angiography in Renal Artery Stent Evaluation: Prospective Comparison with Intra-Arterial Digital Subtraction Angiography

    International Nuclear Information System (INIS)

    Raza, Syed A.; Chughtai, Aamer R.; Wahba, Mona; Cowling, Mark G.; Taube, David; Wright, Andrew R.

    2004-01-01

    Purpose: To assess the role of multislice computed tomography angiography (MCTA) in the evaluation of renal artery stents, using intra-arterial digital subtraction angiography (DSA) as the gold standard. Methods: Twenty consecutive patients (15 men, 5 women) with 23 renal artery stents prospectively underwent both MCTA and DSA. Axial images, multiplanar reconstructions and maximum intensity projection images were used for diagnosis. The MCTA and DSA images were each interpreted without reference to the result of the other investigation. Results:The three cases of restenosis on DSA were detected correctly by MCTA; in 19 cases where MCTA showed a fully patent stent, the DSA was also negative. Sensitivity and negative predictive value (NPV) of MCTA were therefore 100%. In four cases, MCTA showed apparently minimal disease which was not shown on DSA. These cases are taken as false positive giving a specificity of 80% and a positive predictive value of 43%. Conclusion: The high sensitivity and NPV suggest MCTA may be useful as a noninvasive screen for renal artery stentrestenosis. MCTA detected mild disease in a few patients which was not confirmed on angiography

  11. Investigation of renovascular hypertension with 99mTC-DTPA dynamic renal scanning and digital subtraction angiography

    International Nuclear Information System (INIS)

    Stavraka-Kakavakis, A.; Vlontjou, E.; Apostolopoulos, D.; Mourikis, D.; Venetsanakis, N.; Lazarou, S.; Vlahos, L.

    1989-01-01

    Sixty-four selected hypertensive patients, aged 17-45 years, were evaluated for renovascular hypertension. They were studied with 99m TC-DTPA dynamic renal scanning (DRS) and intravenous digital subtraction angiography (IV-DSA). Intra-arterial DSA was further performed to demonstrate renal vascular anatomy in all disputable cases. Agreement of diagnosis occurred in 58 patients (32 with renal artery stenosis). There was one false positive with DRS and one false positive with IV-DSA. In another four patients with proven renovascular disease, IV-DSA was positive while DRS negative, but in two of them the stenotic lesion was considered insignificant, as they failed to respond to percutaneous transluminal dilatation (PTA). In contrast, nearly all patients whose hypertension improved after PTA or surgery had positive DRS and greater than 40% reduction of relative function of the affected kidney. IV-DSA yielded better results than DRS in the detection of renal arterial stenosis (especially whenever bilateral stenosis or rich collateral circulation was present), but DRS showed better correlation with the functional significance of a certain vascular abnormality. Thus the combination of the two methods seems to be a reasonable diagnostic approach to hypertensive patients with the aim of selecting those with curable hypertension due to renal vascular disease. (orig.)

  12. Synchrotron-based intra-venous K-edge digital subtraction angiography in a pig model: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Schueltke, Elisabeth [Departments of Surgery, University of Saskatchewan, Saskatoon, SK (Canada); Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, SK (Canada); Department of Neurological Sciences, Walton Medical Centre, University of Liverpool, Liverpool L97 LJ (United Kingdom)], E-mail: e.schultke@usask.ca; Fiedler, Stefan [European Molecular Biology Laboratory (EMBL), Nottkestrasse 85, 22603 Hamburg (Germany); Nemoz, Christian [European Synchrotron Radiation Facility (ESRF), 6 rue Horowitz, 38043 Grenoble (France); Ogieglo, Lissa [Departments of Surgery, University of Saskatchewan, Saskatoon, SK (Canada); Kelly, Michael E. [Departments of Surgery, University of Saskatchewan, Saskatoon, SK (Canada); Department of Neurosurgery, Section of Cerebrovascular and Endovascular Neurosurgery, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH (United States); Crawford, Paul [Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herfordshire AL9 7TA (United Kingdom); Esteve, Francois [INSERM U836-ESRF, 6 rue Horowitz, 38043 Grenoble (France); Brochard, Thierry; Renier, Michel; Requardt, Herwig; Le Duc, Geraldine [European Synchrotron Radiation Facility (ESRF), 6 rue Horowitz, 38043 Grenoble (France); Juurlink, Bernhard [Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, SK (Canada); Meguro, Kotoo [Departments of Surgery, University of Saskatchewan, Saskatoon, SK (Canada)

    2010-03-15

    Background: K-edge digital subtraction angiography (KEDSA) combined with the tunability of synchrotron beam yields an imaging technique that is highly sensitive to low concentrations of contrast agents. Thus, contrast agent can be administered intravenously, obviating the need for insertion of a guided catheter to deliver a bolus of contrast agent close to the target tissue. With the high-resolution detectors used at synchrotron facilities, images can be acquired at high spatial resolution. Thus, the KEDSA appears particularly suited for studies of neurovascular pathology in animal models, where the vascular diameters are significantly smaller than in human patients. Materials and methods: This feasibility study was designed to test the suitability of KEDSA after intravenous injection of iodine-based contrast agent for use in a pig model. Four adult male pigs were used for our experiments. Neurovascular angiographic images were acquired using KEDSA with a solid state Germanium (Ge) detector at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Results: After intravenous injection of 0.9 ml/kg iodinated contrast agent (Xenetix), the peak iodine concentrations in the internal carotid and middle cerebral arteries reached 35 mg/ml. KEDSA images in radiography mode allowed the visualization of intracranial arteries of less than 1.5 mm diameter.

  13. Comparison of digital subtraction angiography with gadolinium-enhanced magnetic resonance angiography in the diagnosis of renal artery stenosis

    International Nuclear Information System (INIS)

    Thornton, J.; O'Callaghan, J.; Varghese, J.C.; Lee, M.J.; Walshe, J.; O'Brien, E.

    1999-01-01

    Renal artery stenosis (RAS) is a treatable cause of hypertension and renal failure for which no ideal screening technique is currently available. We evaluated the use of dynamic gadolinium-enhanced magnetic resonance angiography (MRA) for the diagnosis of RAS. Sixty-two patients with secondary hypertension were enrolled in the study. All patients had conventional renal angiography and gadolinium enhanced MRA. The sequence used was a 3D FMP SPGR sequence with the following parameters (TR: 26 ms, TE: 6.9 ms, flip angle 40 , field of view 36 x 36 cm, matrix 246 x 256, 1 excitation). Gadolinium 0.3 mmol/kg was administered and 60 1.5-mm-thick partitions were obtained over a duration of 3.5 min. The MRA images were then compared with conventional digital subtraction angiography (DSA) images. Conventional DSA demonstrated 138 renal arteries, whereas gadolinium-enhanced MRA demonstrated 129 (93 %). Twenty-one renal artery stenoses and four occluded arteries were seen at conventional DSA. Gadolinium-enhanced MRA had a sensitivity of 88 %, specificity of 98 %, accuracy of 96 %, positive predictive value of 92 % and negative predictive value of 97 % when compared with conventional DSA. Gadolinium-enhanced MRA is an accurate technique for identifying patients with RAS. It is less sensitive in picking up accessory renal arteries. (orig.)

  14. Contrast-enhanced MR angiography vs intra-arterial digital subtraction angiography for carotid imaging: activity-based cost analysis

    International Nuclear Information System (INIS)

    U-King-Im, Jean Marie; Cross, Justin J.; Higgins, Nicholas J.; Graves, Martin J.; Antoun, Nagui M.; Gillard, Jonathan H.; Hollingworth, William; Trivedi, Rikin A.; Kirkpatrick, Peter J.

    2004-01-01

    The aim of this study was to compare the costs of performing contrast-enhanced MR angiography (CE MRA) with intra-arterial digital subtraction angiography (DSA) for the evaluation of carotid atherosclerotic disease. Activity-based cost analysis was used to identify the costs of performing each procedure. The variable direct costs of performing CE MRA and DSA were determined in 20 patients by using detailed time and motion studies. All personnel directly involved in the cases were tracked to the nearest minute and all consumable items used were recorded. Moreover, procedure times were prospectively recorded for an additional 80 patients who underwent both DSA and CE MRA. The variable direct costs of bed usage in the angiography day-case unit, all direct fixed costs as well as indirect costs were assessed from hospital and departmental accounting records. Total costs for each procedure were calculated and compared using Wilcoxon signed-rank sum test. Mean aggregate costs were and euro;721 for DSA and and euro;306 for CE MRA, resulting in potential savings of and euro;415 per patient (p<0.0001). On average, a DSA procedure thus cost approximately 2.4 (95% confidence intervals: 2.2-2.6) times more than CE MRA to our medical institution. Sensitivity analyses confirmed the robustness of our conclusions across wide ranges of plausible values for various parameters. Assuming equal diagnostic performance, institutions may have substantial cost savings if CE MRA is used instead of DSA for carotid imaging. (orig.)

  15. Contrast-enhanced MR angiography vs intra-arterial digital subtraction angiography for carotid imaging: activity-based cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    U-King-Im, Jean Marie; Cross, Justin J.; Higgins, Nicholas J.; Graves, Martin J.; Antoun, Nagui M.; Gillard, Jonathan H. [University Department of Radiology, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Hollingworth, William [Department of Radiology, University of Washington, WA 98103, Seattle (United States); Trivedi, Rikin A. [University Department of Radiology, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Academic Department of Neurosurgery, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Kirkpatrick, Peter J. [Academic Department of Neurosurgery, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom)

    2004-04-01

    The aim of this study was to compare the costs of performing contrast-enhanced MR angiography (CE MRA) with intra-arterial digital subtraction angiography (DSA) for the evaluation of carotid atherosclerotic disease. Activity-based cost analysis was used to identify the costs of performing each procedure. The variable direct costs of performing CE MRA and DSA were determined in 20 patients by using detailed time and motion studies. All personnel directly involved in the cases were tracked to the nearest minute and all consumable items used were recorded. Moreover, procedure times were prospectively recorded for an additional 80 patients who underwent both DSA and CE MRA. The variable direct costs of bed usage in the angiography day-case unit, all direct fixed costs as well as indirect costs were assessed from hospital and departmental accounting records. Total costs for each procedure were calculated and compared using Wilcoxon signed-rank sum test. Mean aggregate costs were and euro;721 for DSA and and euro;306 for CE MRA, resulting in potential savings of and euro;415 per patient (p<0.0001). On average, a DSA procedure thus cost approximately 2.4 (95% confidence intervals: 2.2-2.6) times more than CE MRA to our medical institution. Sensitivity analyses confirmed the robustness of our conclusions across wide ranges of plausible values for various parameters. Assuming equal diagnostic performance, institutions may have substantial cost savings if CE MRA is used instead of DSA for carotid imaging. (orig.)

  16. Suppression of high-density artefacts in x-ray CT images using temporal digital subtraction with application to cryotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Baissalov, R.; Sandison, G.A.; Rewcastle, J.C. [Department of Medical Physics, Tom Baker Cancer Center, Calgary, Canada, T2N 4N2 2 Department of Physics and Astronomy, University of Calgary, Calgary T2N 2N4 (Canada); Donnelly, B.J. [Department of Surgery, Tom Baker Cancer Center, Calgary, Canada, T2N 4N2 4 Department of Surgery, Foothills Hospital, Calgary T2N 2T7 (Canada); Saliken, J.C. [Department of Surgery, Tom Baker Cancer Center, Calgary T2N 4N2 (Canada); Department of Diagnostic Imaging, Foothills Hospital, Calgary T2N 2T7 (Canada); McKinnon, J.G. [Department of Surgery, Foothills Hospital, Calgary T2N 2T7 (Canada); Muldrew, K. [Department of Surgery, Faculty of Medicine, University of Calgary, Calgary T2N 2T7 (Canada)

    2000-05-01

    Image guidance in cryotherapy is usually performed using ultrasound. Although not currently in routine clinical use, x-ray CT imaging is an alternative means of guidance that can display the full 3D structure of the iceball, including frozen and unfrozen regions. However, the quality of x-ray CT images is compromised by the presence of high-density streak artefacts. To suppress these artefacts we applied temporal digital subtraction (TDS). This TDS method has the added advantage of improving the grey-scale contrast between frozen and unfrozen tissue in the CT images. Two sets of CT images were taken of a phantom material, cryoprobes and a urethral warmer (UW) before and during the cryoprobe freeze cycle. The high-density artefacts persisted in both image sets. TDS was performed on these two image sets using the corresponding mask image of unfrozen material and the same geometrical configuration of the cryoprobes and the UW. The resultant difference image had a significantly reduced artefact content. Thus TDS can be used to significantly suppress or eliminate high-density CT streak artefacts without reducing the metallic content of the cryoprobes. In vivo study needs to be conducted to establish the utility of this TDS procedure for CT assisted prostate or liver cryotherapy. Applying TDS in x-ray CT guided cryotherapy will facilitate estimation of the number and location of all frozen and unfrozen regions, potentially making cryotherapy safer and less operator dependent. (author)

  17. Suppression of high-density artefacts in x-ray CT images using temporal digital subtraction with application to cryotherapy

    International Nuclear Information System (INIS)

    Baissalov, R.; Sandison, G.A.; Rewcastle, J.C.; Donnelly, B.J.; Saliken, J.C.; McKinnon, J.G.; Muldrew, K.

    2000-01-01

    Image guidance in cryotherapy is usually performed using ultrasound. Although not currently in routine clinical use, x-ray CT imaging is an alternative means of guidance that can display the full 3D structure of the iceball, including frozen and unfrozen regions. However, the quality of x-ray CT images is compromised by the presence of high-density streak artefacts. To suppress these artefacts we applied temporal digital subtraction (TDS). This TDS method has the added advantage of improving the grey-scale contrast between frozen and unfrozen tissue in the CT images. Two sets of CT images were taken of a phantom material, cryoprobes and a urethral warmer (UW) before and during the cryoprobe freeze cycle. The high-density artefacts persisted in both image sets. TDS was performed on these two image sets using the corresponding mask image of unfrozen material and the same geometrical configuration of the cryoprobes and the UW. The resultant difference image had a significantly reduced artefact content. Thus TDS can be used to significantly suppress or eliminate high-density CT streak artefacts without reducing the metallic content of the cryoprobes. In vivo study needs to be conducted to establish the utility of this TDS procedure for CT assisted prostate or liver cryotherapy. Applying TDS in x-ray CT guided cryotherapy will facilitate estimation of the number and location of all frozen and unfrozen regions, potentially making cryotherapy safer and less operator dependent. (author)

  18. Variations and Anomalies of the circle of Willis in Korean: Cerebral digital subtraction angiogram studies in 200 case

    International Nuclear Information System (INIS)

    Lee, Ouk; Chung, Gyoo Sik; Kim, So Sun; Huh, Jin Do; Kim, Ho Joon; Joh, Young Duk

    1989-01-01

    In order to evaluate the variations of the circle of Willis in Korean population, digital subtraction angiograms in 200 cases were retrospectively analyzed. There was non-visualization of the anterior communicating artery and the posterior communicating artery in 41 cases and this was the most common type 4 vessel cerebral angiogram (20.5%). Unilateral or bilateral non-visualization of the posterior communicating artery was noted in 40 case (20%). The fetal origin of the posterior cerebral artery from the internal carotid artery was seen in 22 cases (11%). In 20 out of 22 cases, there were non-visualization of either the anterior communicating or posterior communicating artery. Visualization of the anterior communicating artery was noted in 102 cases (51%) and of the posterior communicating artery in 87 cases (43.5%). Hypoplasia of the anterior cerebral artery was noted in 24 cases (12%). Non- visualization of the anterior communicating artery or unilateral posterior communicating artery is noted in 16 cases (8%). Non- visualization of the anterior communicating artery was seen in 14 cases (7%). The most common type in appearance of the basilar artery variation was straight type (Type 1: 51%) and the bifurcation of the basilar artery was most commonly located above the posterior clinoid process of the dorsum sellae (58%) on vertebral angiogram

  19. Synchrotron-based intra-venous K-edge digital subtraction angiography in a pig model: A feasibility study

    International Nuclear Information System (INIS)

    Schueltke, Elisabeth; Fiedler, Stefan; Nemoz, Christian; Ogieglo, Lissa; Kelly, Michael E.; Crawford, Paul; Esteve, Francois; Brochard, Thierry; Renier, Michel; Requardt, Herwig; Le Duc, Geraldine; Juurlink, Bernhard; Meguro, Kotoo

    2010-01-01

    Background: K-edge digital subtraction angiography (KEDSA) combined with the tunability of synchrotron beam yields an imaging technique that is highly sensitive to low concentrations of contrast agents. Thus, contrast agent can be administered intravenously, obviating the need for insertion of a guided catheter to deliver a bolus of contrast agent close to the target tissue. With the high-resolution detectors used at synchrotron facilities, images can be acquired at high spatial resolution. Thus, the KEDSA appears particularly suited for studies of neurovascular pathology in animal models, where the vascular diameters are significantly smaller than in human patients. Materials and methods: This feasibility study was designed to test the suitability of KEDSA after intravenous injection of iodine-based contrast agent for use in a pig model. Four adult male pigs were used for our experiments. Neurovascular angiographic images were acquired using KEDSA with a solid state Germanium (Ge) detector at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Results: After intravenous injection of 0.9 ml/kg iodinated contrast agent (Xenetix), the peak iodine concentrations in the internal carotid and middle cerebral arteries reached 35 mg/ml. KEDSA images in radiography mode allowed the visualization of intracranial arteries of less than 1.5 mm diameter.

  20. Synchrotron-based intra-venous K-edge digital subtraction angiography in a pig model: a feasibility study.

    Science.gov (United States)

    Schültke, Elisabeth; Fiedler, Stefan; Nemoz, Christian; Ogieglo, Lissa; Kelly, Michael E; Crawford, Paul; Esteve, Francois; Brochard, Thierry; Renier, Michel; Requardt, Herwig; Le Duc, Geraldine; Juurlink, Bernhard; Meguro, Kotoo

    2010-03-01

    K-edge digital subtraction angiography (KEDSA) combined with the tunability of synchrotron beam yields an imaging technique that is highly sensitive to low concentrations of contrast agents. Thus, contrast agent can be administered intravenously, obviating the need for insertion of a guided catheter to deliver a bolus of contrast agent close to the target tissue. With the high-resolution detectors used at synchrotron facilities, images can be acquired at high spatial resolution. Thus, the KEDSA appears particularly suited for studies of neurovascular pathology in animal models, where the vascular diameters are significantly smaller than in human patients. This feasibility study was designed to test the suitability of KEDSA after intravenous injection of iodine-based contrast agent for use in a pig model. Four adult male pigs were used for our experiments. Neurovascular angiographic images were acquired using KEDSA with a solid state Germanium (Ge) detector at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. After intravenous injection of 0.9 ml/kg iodinated contrast agent (Xenetix), the peak iodine concentrations in the internal carotid and middle cerebral arteries reached 35 mg/ml. KEDSA images in radiography mode allowed the visualization of intracranial arteries of less than 1.5mm diameter. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  1. Nonlinear Geometric Warping of the Mask Image: A New Method for Reducing Misregistration Artifacts in Digital Subtraction Angiography

    International Nuclear Information System (INIS)

    Hayashi, Nobushige; Sakai, Toyohiko; Kitagawa, Manabu; Inagaki, Rika; Sadato, Norihiro; Ishii, Yasushi; Nishimoto, Yasuhiro; Tanaka, Masato; Fukushima, Tetsuya; Komuro, Hiroyuki; Ogura, Hisakazu; Kobayashi, Hidenori; Kubota, Toshihiko

    1998-01-01

    Purpose: Misregistration artifact is the major cause of image degradation in digital subtraction angiography (DSA). The purpose of this study was to evaluate the efficacy of a newly developed nonlinear geometric warping method to reduce misregistration artifact in DSA. Methods: The processing of the images was carried out on a workstation with a fully automatic computerized program. After making differential images with a lapracian filter, 49 regions of interest (ROIs) were set in the image to be processed. Each ROI of the live image scanned the corresponding ROI of the mask image searching for the best position to match itself. Each pixel of the mask image was shifted individually following the data calculated from the shifts of the ROIs. Five radiologists compared the images produced by the conventional parallel shift technique and those processed with this new method in 16 series of cerebral DSA. Results: In 14 of 16 series (88%), more radiologists judged the images processed with the new method to be better in quality. Small arteries near the skull base and veins of low density were clearly visualized in the images processed by the new method. Conclusion: This newly proposed method could be a simple and practical way to automatically reduce misregistration artifacts in DSA

  2. Intra-arterial digital subtraction portography with a blood-isotonic, non-ionic, dimeric contrast medium

    International Nuclear Information System (INIS)

    Minakuchi, Kazuo; Tamaoka, Koichi; Nishio, Hiroshi; Matsuo, Ryoichi; Takada, Keiji; Morimoto, Atsuko; Toyoshima, Masami; Murata, Katsuko; Onoyama, Yasuto

    1993-01-01

    Intra-arterial digital subtraction portography (IA-DSP) with a blood-isotonic, non-ionic, dimeric contrast medium was carried out in 27 patients with hepatocellular carcinoma. It was possible to obtain images of excellent or good quality of the portal vein and its bilateral main branches in all patients. The third-order branches of the portal vein in the right lobe could be identified in all patients, and images of excellent or good quality were obtained in a mean of 80.2% of patients. Images of third-order branches in the left lobe were of lower quality than those of third-order branches in the right lobe; in particular, images obtained were of poor quality for 27.3% of the medial branches of the left lobe. It was impossible to identify the caudal branches in almost all patients. The side effects of IA-DSP, pain and sensations of heat were very mild; only one patient complained of mild pain, while 18 patients (69.2%) complained of no sensations of heat whatsoever. (author)

  3. Rotational digital subtraction angiography of the renal arteries: technique and evaluation in the study of native and transplant renal arteries.

    Science.gov (United States)

    Seymour, H R; Matson, M B; Belli, A M; Morgan, R; Kyriou, J; Patel, U

    2001-02-01

    Rotational digital subtraction angiography (RDSA) allows multidirectional angiographic acquisitions with a single injection of contrast medium. The role of RDSA was evaluated in 60 patients referred over a 7-month period for diagnostic renal angiography and 12 patients referred for renal transplant studies. All angiograms were assessed for their diagnostic value, the presence of anomalies and the quantity of contrast medium used. The effective dose for native renal RDSA was determined. 41 (68.3%) native renal RDSA images and 8 (66.7%) transplant renal RDSA images were of diagnostic quality. Multiple renal arteries were identified in 9/41 (22%) native renal RDSA diagnostic images. The mean volume of contrast medium in the RDSA runs was 51.2 ml and 50 ml for native and transplant renal studies, respectively. The mean effective dose for 120 degrees native renal RDSA was 2.36 mSv, equivalent to 1 year's mean background radiation. Those RDSA images that were non-diagnostic allowed accurate prediction of the optimal angle for further static angiographic series, which is of great value in transplant renal vessels.

  4. Diagnostic value of the digital subtraction angiography of brain tumors. With special reference to the significance of tumor stains

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Yoshifumi; Matsukado, Yasuhiko; Takahashi, Mutsumasa

    1986-10-01

    Digital subtraction angiography (DSA) in 110 cases of brain tumors were studied in comparison with conventional angiography (CA). The dural sinuses and tumor stains of meningiomas, particularly tuberculum sellae meningioma, were better shown by intravenous DSA (IV-DSA) than by CA. IV-DSA clearly demonstrated bilateral carotid arteries and was able to rule out the coexistence of the intracranial aneurysm in 88 % of 32 cases with pituitary adenomas. Combination of IV-DSA and high resolution computed tomography has replaced CA to determine surgical indication of patients with pituitary adenomas. Intra-arterial DSA (IA-DSA) was diagnostic and well comparable to CA in identifying main cerebral vasculature over 1 mm in diameter. As to the small arteries under 1 mm and fine tumor vessels, IA-DSA provided less information or none at all. However, IA-DSA was superior to CA for visualization of tumor stains. Not only in most of meningiomas and hemangioblastomas, but in some astrocytomas and oligodendrogliomas, marked tumor stains were well demonstrated on DSA, and DSA provided surgical anatomy for neurosurgeons because of high contrast resolutions. Careful attention should be paid because tumor stains may overestimate tumor vascularity.

  5. Detection of unruptured familial intracranial aneurysms by intravenous digital subtraction angiography

    International Nuclear Information System (INIS)

    Berg, H.W.M. ter; Regional Hospital Almelo; Overtoom, T.M.D.; Ludwig, J.W.; Bijlsma, J.B.; Tulleken, C.A.F.; Willemse, J.

    1987-01-01

    The authors discuss the detection of intracranial aneurysms (IA) by means of intravenous digital angiography (ivDSA) in (a)symptomatic first degree relatives of families in which more than two or more individuals have IA. ivDSA is an almost noninvasive and low-risk diagnostic procedure. Screening, by means of ivDSA, of two affected families is described. In family I which includes 7 members with proven IA, ivDSA has been carried out in 36 asymptomatic individuals: in one, a 6x15 mm aneurysm was found at the left posterior communicating artery (PCoA). In family II, including one member with a proven IA and another with a subarachnoidal hemorrhage, ivDSA has been carried out in 4 members: one aneurysm with a diameter of 6 mm was found at the left PCoA. Conventional cerebral angiography (CCA) confirmed both IA's. Neurosurgical treatment followed. The advantages and disadvantages of ivDSA vs. CCA as elective screening procedure in such cases are discussed. Screening of asymptomatic first degree relatives of cases with familial IA by means of ivDSA is strongly advocated. (orig.)

  6. Marginal Accuracy and Internal Fit of Dental Copings Fabricated by Modern Additive and Subtractive Digital Technologies.

    Science.gov (United States)

    Nelson, Neha; K S, Jyothi; Sunny, Kiran

    2017-03-01

    The margins of copings for crowns and retainers of fixed partial dentures affect the progress of microleakage and dental caries. Failures occur due to altered fit which is also influenced by the method of fabrication. An in-vitro study was conducted to determine among the cast base metal, copy milled zirconia, computer aided designing computer aided machining/manufacturing zirconia and direct metal laser sintered copings which showed best marginal accuracy and internal fit. Forty extracted maxillary premolars were mounted on an acrylic model and reduced occlusally using a milling machine up to a final tooth height of 4 mm from the cementoenamel junction. Axial reduction was accomplished on a surveyor and a chamfer finish line was given. The impressions and dies were made for fabrication of copings which were luted on the prepared teeth under standardized loading, embedded in self-cure acrylic resin, sectioned and observed using scanning electron microscope for internal gap and marginal accuracy. The copings fabricated using direct metal laser sintering technique exhibited best marginal accuracy and internal fit. Comparison of mean between the four groups by ANOVA and post-hoc Tukey HSD tests showed a statistically significant difference between all the groups (p⟨0.05). It was concluded that the copings fabricated using direct metal laser sintering technique exhibited best marginal accuracy and internal fit. Additive digital technologies such as direct metal laser sintering could be cost-effective for the clinician, minimize failures related to fit and increase longevity of teeth and prostheses. Copyright© 2017 Dennis Barber Ltd.

  7. An automatic fuzzy-based multi-temporal brain digital subtraction angiography image fusion algorithm using curvelet transform and content selection strategy.

    Science.gov (United States)

    Momeni, Saba; Pourghassem, Hossein

    2014-08-01

    Recently image fusion has prominent role in medical image processing and is useful to diagnose and treat many diseases. Digital subtraction angiography is one of the most applicable imaging to diagnose brain vascular diseases and radiosurgery of brain. This paper proposes an automatic fuzzy-based multi-temporal fusion algorithm for 2-D digital subtraction angiography images. In this algorithm, for blood vessel map extraction, the valuable frames of brain angiography video are automatically determined to form the digital subtraction angiography images based on a novel definition of vessel dispersion generated by injected contrast material. Our proposed fusion scheme contains different fusion methods for high and low frequency contents based on the coefficient characteristic of wrapping second generation of curvelet transform and a novel content selection strategy. Our proposed content selection strategy is defined based on sample correlation of the curvelet transform coefficients. In our proposed fuzzy-based fusion scheme, the selection of curvelet coefficients are optimized by applying weighted averaging and maximum selection rules for the high frequency coefficients. For low frequency coefficients, the maximum selection rule based on local energy criterion is applied to better visual perception. Our proposed fusion algorithm is evaluated on a perfect brain angiography image dataset consisting of one hundred 2-D internal carotid rotational angiography videos. The obtained results demonstrate the effectiveness and efficiency of our proposed fusion algorithm in comparison with common and basic fusion algorithms.

  8. MRA versus digital subtraction angiography in acute subarachnoid haemorrhage: a blinded multireader study of prospectively recruited patients

    International Nuclear Information System (INIS)

    Jaeger, H.R.; Hausmann, O.; Moseley, I.F.; Taylor, W.J.; Mansmann, U.; Partzsch, U.

    2000-01-01

    We performed a blinded multireader study comparing MR angiography (MRA) with digital subtraction angiography (DSA) in 34 prospectively recruited patients who presented with acute subarachnoid haemorrhage (SAH). Two observers independently reviewed the MRA and DSA studies some months after clinical presentation. Presence of an aneurysm was rated on a 4-point confidence scale. Cases in which the initial interpretation of the observers varied were jointly reviewed to reach a consensus opinion. DSA was deliberately chosen not to represent the reference standard and the clinical course and surgical findings were used to explain significant differences between the consensus readings of MRA and DSA. Diagnostic confidence and interobserver agreement were, overall, higher on DSA than on MRA studies (κ DSA = 0.64 versus κ MRA = 0.52 with 95 % CI for Δ = κ DSA -κ MRA [-0.06, 0.31]). With both methods, discrepancies between observers were due to aneurysms overlooked rather than false-positive readings by one observer. Diagnostic accuracy therefore improved when the readings of the two observers were combined, particularly for MRA. Intermethod agreement was only fair and similar for both readers (κ reader 1 = 0.37 versus κ reader 2 = 0.32 with 95 % CI for Δ = κ reader 1 -κ reader 2 [-0.02, 0.11]). Both interobserver and intermethod agreements improved when the data were analysed on a per-study (positive or negative study) rather than on a per-aneurysm basis. Differences in the consensus reading were due to five aneurysms (four single and one multiple) detected only with MRA and five (two single and three multiple) detected only with DSA. MRA and DSA should be regarded as complementary in the investigation of patients with acute SAH. DSA can no longer be regarded as the reference standard. (orig.)

  9. CT Angiography of Peripheral Arterial Disease by 256-Slice Scanner: Accuracy, Advantages and Disadvantages Compared to Digital Subtraction Angiography.

    Science.gov (United States)

    Mishra, Atul; Jain, Narendra; Bhagwat, Anand

    2017-07-01

    Peripheral arterial occlusive disease (PAOD) may cause disabling claudication or critical limb ischemia. Multidetector computed tomography (CT) technology has evolved to the level of 256-slice CT scanners which has significantly improved the spatial and temporal resolution of the images. This has provided the capability of chasing the contrast bolus at a fast speed enabling angiographic imaging of long segments of the body. These images can be reconstructed in various planes and various modes for detailed analysis of the peripheral vascular diseases which helps in making treatment decision. The aim of this retrospective study was to compare the CT angiograms (CTAs) of all cases of PAOD done by 256-slice CT scanner at a tertiary care vascular center and comparing these images with the digital subtraction angiograms (DSAs) of these patients. The retrospective study included 53 patients who underwent both CTA and DSA at our center over a period of 3 years from March 2013 to March 2016. The CTA showed high sensitivity (93%) and specificity (92.7%) for overall assessment of degree of stenosis in a vascular segment in cases of aortic and lower limb occlusive disease. The assessment of lesions of infrapopliteal segment was comparatively inferior (sensitivity 91.6%, accuracy 73.3%, and positive predictive value 78.5%), more so in the presence of significant calcification. The advantages of CTA were its noninvasive nature, ability to image large area of body, almost no adverse effects to the patients, and better assessment of vessel wall disease. However, the CTA assessment of collaterals was inferior with a sensitivity of only 62.7% as compared to DSA. Overall, 256-slice CTA provides fast and accurate imaging of vascular tree which can restrict DSA only in few selected cases as a problem-solving tool where clinico-radiological mismatch is present.

  10. Utility of digital subtraction angiography-based collateral evaluation in medically treated acute symptomatic basilar artery stenosis.

    Science.gov (United States)

    Lee, W-J; Jung, K-H; Ryu, Y J; Kim, J-M; Lee, S-T; Chu, K; Kim, M; Lee, S K; Roh, J-K

    2017-09-01

    Although a stroke from atherosclerosis in the basilar artery (BA) often presents with mild initial stroke severity, it has heterogeneous clinical courses. We investigated the efficacy of digital subtraction angiography (DSA)-based collateral perfusion evaluation in association with long-term outcomes of medically treated symptomatic basilar artery stenosis. From a registry database of all consecutive patients with stroke, we included 98 medically treated patients (due to mild initial stroke severity) [National Institute of Health Stroke Scale (NIHSS) scores ≤ 4; symptomatic basilar artery stenosis, 70-99%] with available initial diagnostic DSA. Basilar collateral scoring was performed via the DSA, using a modified version of the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system in both the superior cerebellar artery and anterior/posterior-inferior cerebellar artery territories (score 0-8). The outcomes were designated as the 90-day modified Rankin Scale (mRS90) score (poor, 3-6). Student's t-test, chi-square test and logistic regression analyses were used to identify factors associated with a poor outcome. The median initial NIHSS score was 2 [interquartile range (IQR), 0-3], median posterior circulation Alberta Stroke Program Early CT Score was 8 (IQR, 7-10), median collateral score was 7 (IQR, 7-8) and 20 (20.4%) had poor mRS90 scores. In multivariate analysis, poorer collateral scores (P = 0.003), higher NIHSS scores (P = 0.005) and lower posterior circulation Alberta Stroke Program Early CT Score (P = 0.017) were independently associated with a poor mRS90 score. The DSA-based collateral scoring of the BA large branches might predict long-term outcome in medically treated symptomatic basilar artery stenosis with mild initial severity. Evaluation of BA collateral perfusion status might be useful to determine appropriate treatment strategies. © 2017 EAN.

  11. Intra-Arterial MR Perfusion Imaging of Meningiomas: Comparison to Digital Subtraction Angiography and Intravenous MR Perfusion Imaging.

    Directory of Open Access Journals (Sweden)

    Mark A Lum

    Full Text Available To evaluate the ability of IA MR perfusion to characterize meningioma blood supply.Studies were performed in a suite comprised of an x-ray angiography unit and 1.5T MR scanner that permitted intraprocedural patient movement between the imaging modalities. Patients underwent intra-arterial (IA and intravenous (IV T2* dynamic susceptibility MR perfusion immediately prior to meningioma embolization. Regional tumor arterial supply was characterized by digital subtraction angiography and classified as external carotid artery (ECA dural, internal carotid artery (ICA dural, or pial. MR perfusion data regions of interest (ROIs were analyzed in regions with different vascular supply to extract peak height, full-width at half-maximum (FWHM, relative cerebral blood flow (rCBF, relative cerebral blood volume (rCBV, and mean transit time (MTT. Linear mixed modeling was used to identify perfusion curve parameter differences for each ROI for IA and IV MR imaging techniques. IA vs. IV perfusion parameters were also directly compared for each ROI using linear mixed modeling.18 ROIs were analyzed in 12 patients. Arterial supply was identified as ECA dural (n = 11, ICA dural (n = 4, or pial (n = 3. FWHM, rCBV, and rCBF showed statistically significant differences between ROIs for IA MR perfusion. Peak Height and FWHM showed statistically significant differences between ROIs for IV MR perfusion. RCBV and MTT were significantly lower for IA perfusion in the Dural ECA compared to IV perfusion. Relative CBF in IA MR was found to be significantly higher in the Dural ICA region and MTT significantly lower compared to IV perfusion.

  12. Extrahepatic Arteries Originating from Hepatic Arteries: Analysis Using CT During Hepatic Arteriography and Visualization on Digital Subtraction Angiography

    International Nuclear Information System (INIS)

    Ozaki, Kumi; Kobayashi, Satoshi; Matsui, Osamu; Minami, Tetsuya; Koda, Wataru; Gabata, Toshifumi

    2017-01-01

    PurposeTo investigate the prevalence and site of origin of extrahepatic arteries originating from hepatic arteries on early phase CT during hepatic arteriography (CTHA) was accessed. Visualization of these elements on digital subtraction hepatic angiography (DSHA) was assessed using CTHA images as a gold standard.Materials and MethodsA total of 943 patients (mean age 66.9 ± 10.3 years; male/female, 619/324) underwent CTHA and DSHA. The prevalence and site of origin of extrahepatic arteries were accessed using CTHA and visualized using DSHA.ResultsIn 924 (98.0%) patients, a total of 1555 extrahepatic branches, representing eight types, were found to originate from hepatic arteries on CTHA. CTHA indicated the following extrahepatic branch prevalence rates: right gastric artery, 890 (94.4%); falciform artery, 386 (40.9%); accessory left gastric artery, 161 (17.1%); left inferior phrenic artery (IPA), 43 (4.6%); posterior superior pancreaticoduodenal artery, 33 (3.5%); dorsal pancreatic artery, 26 (2.8%); duodenal artery, 12 (1.3%); and right IPA, 4 (0.4%). In addition, 383 patients (40.6%) had at least one undetectable branch on DSHA. The sensitivity, specificity, and accuracy of visualization on DSHA were as follows: RGA, 80.0, 86.8, and 80.4%; falciform artery, 53.9, 97.7, and 80.0%; accessory LGA, 64.6, 98.6, and 92.3%; left IPA, 76.7, 99.8, and 98.7%; PSPDA, 100, 99.7, and 99.9%; dorsal pancreatic artery, 57.7, 100, and 98.8%; duodenal artery, 8.3, 99.9, and 98.7%; and right IPA, 0, 100, and 99.6%, respectively.ConclusionExtrahepatic arteries originating from hepatic arteries were frequently identified on CTHA images. These arteries were frequently overlooked on DSHA.

  13. Correlation Between Contrast Time-Density Time on Digital Subtraction Angiography and Flow: An in Vitro Study.

    Science.gov (United States)

    Brunozzi, Denise; Shakur, Sophia F; Ismail, Rahim; Linninger, Andreas; Hsu, Chih-Yang; Charbel, Fady T; Alaraj, Ali

    2018-02-01

    Digital subtraction angiography (DSA) provides an excellent anatomic characterization of cerebral vasculature, but hemodynamic assessment is often qualitative and subjective. Various clinical algorithms have been produced to semiquantify flow from the data obtained from DSA, but few have tested them against reliable flow values. An arched flow model was created and injected with contrast material. Seventeen injections were acquired in anterior-posterior and lateral DSA projections, and 4 injections were acquired in oblique projection. Image intensity change over the angiogram cycle of each DSA run was analyzed through a custom MATLAB code. Time-density plots obtained were divided into 3 components (time-density times, TDTs): TDT 10%-100% (time needed for contrast material to change image intensity from 10% to 100%), TDT 100%-10% (time needed for contrast material to change image intensity from 100% to 10%), and TDT 25%-25% (time needed for contrast material to change from 25% image intensity to 25%). Time-density index (TDI) was defined as model cross-sectional area to TDT ratio, and it was measured against different flow rates. TDI 10%-100% , TDI 100%-10% , and TDI 25%-25% all correlated significantly with flow (P < 0.001). TDI 10%-100% , TDI 100%-10% , and TDI 25%-25% showed, respectively, a correlation coefficient of 0.91, 0.91, and 0.97 in the anterior-posterior DSA projections (P < 0.001). In the lateral DSA projection, TDI 100%-10% showed a weaker correlation (r = 0.57; P = 0.03). Also in the oblique DSA projection, TDIs correlated significantly with flow. TDI on DSA correlates significantly with flow. Although in vitro studies might overlook conditions that occur in patients, this method appears to correlate with the flow and could offer a semiquantitative method to evaluate the cerebral blood flow. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Extrahepatic Arteries Originating from Hepatic Arteries: Analysis Using CT During Hepatic Arteriography and Visualization on Digital Subtraction Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Kumi, E-mail: ozakik-rad@umin.org [Kanazawa University Graduate School of Medical Science, Department of Radiology (Japan); Kobayashi, Satoshi [Kanazawa University Graduate School of Medical Science, Department of Quantum Medicine Technology (Japan); Matsui, Osamu; Minami, Tetsuya; Koda, Wataru; Gabata, Toshifumi [Kanazawa University Graduate School of Medical Science, Department of Radiology (Japan)

    2017-06-15

    PurposeTo investigate the prevalence and site of origin of extrahepatic arteries originating from hepatic arteries on early phase CT during hepatic arteriography (CTHA) was accessed. Visualization of these elements on digital subtraction hepatic angiography (DSHA) was assessed using CTHA images as a gold standard.Materials and MethodsA total of 943 patients (mean age 66.9 ± 10.3 years; male/female, 619/324) underwent CTHA and DSHA. The prevalence and site of origin of extrahepatic arteries were accessed using CTHA and visualized using DSHA.ResultsIn 924 (98.0%) patients, a total of 1555 extrahepatic branches, representing eight types, were found to originate from hepatic arteries on CTHA. CTHA indicated the following extrahepatic branch prevalence rates: right gastric artery, 890 (94.4%); falciform artery, 386 (40.9%); accessory left gastric artery, 161 (17.1%); left inferior phrenic artery (IPA), 43 (4.6%); posterior superior pancreaticoduodenal artery, 33 (3.5%); dorsal pancreatic artery, 26 (2.8%); duodenal artery, 12 (1.3%); and right IPA, 4 (0.4%). In addition, 383 patients (40.6%) had at least one undetectable branch on DSHA. The sensitivity, specificity, and accuracy of visualization on DSHA were as follows: RGA, 80.0, 86.8, and 80.4%; falciform artery, 53.9, 97.7, and 80.0%; accessory LGA, 64.6, 98.6, and 92.3%; left IPA, 76.7, 99.8, and 98.7%; PSPDA, 100, 99.7, and 99.9%; dorsal pancreatic artery, 57.7, 100, and 98.8%; duodenal artery, 8.3, 99.9, and 98.7%; and right IPA, 0, 100, and 99.6%, respectively.ConclusionExtrahepatic arteries originating from hepatic arteries were frequently identified on CTHA images. These arteries were frequently overlooked on DSHA.

  15. Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

    International Nuclear Information System (INIS)

    Li Xiaoming; Li Yuhua; Tian Jianming; Xiao Yi; Lu Jianping; Jing Zaiping; Sheng Jing; Edwin, Angela; Wu Fanghong

    2010-01-01

    Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 ± 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion (≥75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

  16. Blood Pool Contrast-enhanced Magnetic Resonance Angiography with Correlation to Digital Subtraction Angiography: A Pictorial Review

    Directory of Open Access Journals (Sweden)

    Martha-Grace Knuttinen

    2014-01-01

    Full Text Available Magnetic resonance angiography (MRA provides noninvasive visualization of the vascular supply of soft tissue masses and vascular pathology, without harmful radiation. This is important for planning an endovascular intervention, and helps to evaluate the efficiency and effectiveness of the treatment. MRA with conventional extracellular contrast agents relies on accurate contrast bolus timing, limiting the imaging window to first-pass arterial phase. The recently introduced blood pool contrast agent (BPCA, gadofosveset trisodium, reversibly binds to human serum albumin, resulting in increased T1 relaxivity and prolonged intravascular retention time, permitting both first-pass and steady-state phase high-resolution imaging. In our practice, high-quality MRA serves as a detailed "roadmap" for the needed endovascular intervention. Cases of aortoiliac occlusive disease, inferior vena cava thrombus, pelvic congestion syndrome, and lower extremity arteriovenous malformation are discussed in this article. MRA was acquired at 1.5 T with an 8-channel phased array coil after intravenous administration of gadofosveset (0.03 mmol/kg body weight, at the first-pass phase. In the steady-state, serial T1-weighted 3D spoiled gradient echo images were obtained with high resolution. All patients underwent digital subtraction angiography (DSA and endovascular treatment. MRA and DSA findings of vascular anatomy and pathology are discussed and correlated. BPCA-enhanced MRA provides high-quality first-pass and steady-state vascular imaging. This could increase the diagnostic accuracy and create a detailed map for pre-intervention planning. Understanding the pharmacokinetics of BPCA and being familiar with the indications and technique of MRA are important for diagnosis and endovascular intervention.

  17. Comparison of X-ray radiation exposure during digital subtraction angiography (DSA) and multislice CT angiography (CTA)

    International Nuclear Information System (INIS)

    Bai, Mei; Liu, Bin; Zheng, Junzheng

    2008-01-01

    Full text: Purpose: To compare radiation risk during digital subtraction angiography (DSA) and CT angiography (CTA). Materials and methods: Eighty patients randomly divided into two groups of 40 patients each, were evaluated for coronary atherosclerotic heart disease with 64-slice spiral CT angiography and DSA respectively. For CTA group we divided patients into two subgroups: regular mode and ECG modulation mode. Matix of thermoluminescent dosimeters (TLDs) were placed on patients' skin surface during each examination to access peak skin dose (PSD). A male ART phantom was equipped with TLDs in six different positions to assess achievable organ dose. Effective dose was calculated by commercially available computer programs. Results: For DSA, PSD was 64mGy. Phantom organ dose for lung, heart, stomach, liver, kidney and brain were 11.07mGy, 5.87mGy, 1.42mGy, 2.11mGy, 6.76mGy and 0.001mGy respectively, and effective dose was 4mSv. For regular mode CTA, PSD was 74.5mGy, and CTD vol was 37.9mGy. Phantom organ dose for lung, heart, stomach, liver, kidney and brain were 58mGy, 64.2mGy, 6.6mGy, 9.9mGy, 2.7mGy, 0.072mGy respectively, and effective dose was 16mSv. For ECG modulation mode, PSD was 50.9mGy, and CTD vol was 26.3mGy. Conclusion: According to measured PSD value, deterministic radiation risk for regular mode CTA was little higher than DSA. However for stochastic radiation risk which can be indicated by organ dose and effective dose, regular mode CTA was much higher than DSA. Comparing with regular mode, ECG modulation mode can effectively reduce both stochastic and deterministic radiation risk. (author)

  18. Radiation dose and image quality of X-ray volume imaging systems: cone-beam computed tomography, digital subtraction angiography and digital fluoroscopy.

    Science.gov (United States)

    Paul, Jijo; Jacobi, Volkmar; Farhang, Mohammad; Bazrafshan, Babak; Vogl, Thomas J; Mbalisike, Emmanuel C

    2013-06-01

    Radiation dose and image quality estimation of three X-ray volume imaging (XVI) systems. A total of 126 patients were examined using three XVI systems (groups 1-3) and their data were retrospectively analysed from 2007 to 2012. Each group consisted of 42 patients and each patient was examined using cone-beam computed tomography (CBCT), digital subtraction angiography (DSA) and digital fluoroscopy (DF). Dose parameters such as dose-area product (DAP), skin entry dose (SED) and image quality parameters such as Hounsfield unit (HU), noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were estimated and compared using appropriate statistical tests. Mean DAP and SED were lower in recent XVI than its previous counterparts in CBCT, DSA and DF. HU of all measured locations was non-significant between the groups except the hepatic artery. Noise showed significant difference among groups (P < 0.05). Regarding CNR and SNR, the recent XVI showed a higher and significant difference compared to its previous versions. Qualitatively, CBCT showed significance between versions unlike the DSA and DF which showed non-significance. A reduction of radiation dose was obtained for the recent-generation XVI system in CBCT, DSA and DF. Image noise was significantly lower; SNR and CNR were higher than in previous versions. The technological advancements and the reduction in the number of frames led to a significant dose reduction and improved image quality with the recent-generation XVI system. • X-ray volume imaging (XVI) systems are increasingly used for interventional radiological procedures. • More modern XVI systems use lower radiation doses compared with earlier counterparts. • Furthermore more modern XVI systems provide higher image quality. • Technological advances reduce radiation dose and improve image quality.

  19. Quantitative digital subtraction radiography in the assessment of external apical root resorption induced by orthodontic therapy: a retrospective study.

    Science.gov (United States)

    Sunku, Raghavendra; Roopesh, R; Kancherla, Pavan; Perumalla, Kiran Kumar; Yudhistar, Palla Venkata; Reddy, V Sridhar

    2011-11-01

    The objective of this study was to evaluate density changes around the apices of teeth during orthodontic treatment by using digital subtraction radiography to measure the densities around six teeth (maxilla central incisors, lateral incisors, and canines) before and after orthodontic treatment in 36 patients and also assess treatment variables and their coorelation with root resorption. A total of 36 consecutive patient files were selected initially. The selected patients presented with a class I or II relationship and were treated with or without premolar extractions and fixed appliances. Some class II patients were treated additionally with extraoral forces or functional appliances. External apical root resorption (EARR) per tooth in millimeters was calculated and was also expressed as a percentage of the original root length. Image reconstruction and subtraction were performed using the software Regeemy Image Registration and Mosaicing (version 0.2.43-RCB, DPI-INPE, Sao Jose dos Campos, Sao Paulo, Brazil) by a single operator. A region of interest (ROI) was defined in the apical third of the root and density calibration was made in Image J® using enamel (gray value = 255) as reference in the same image. The mean gray values in the ROIs were reflective of the change in the density values between the two images. The root resorption of the tooth and the factors of malocclusion were analyzed with a one-way ANOVA. An independent t-test was performed to compare the mean amount of resorption between male and female, between extraction and nonextraction cases. The density changes after orthodontic treatment were analyzed using the Wilcoxon signedrank test. In addition, the density changes in different teeth were analyzed using the Kruskal-Wallis test. The cut-off for statistical significance was a p-value of 0.05. All the statistical analyses were carried out using SPSS (version 13.0 for Windows, Chicago, IL, USA). Gender, the age at which treatment was started and

  20. A comparison of subtracted images from dental subtraction programs

    International Nuclear Information System (INIS)

    Han, Won Jeong

    2002-01-01

    To compare the standard deviation of gray levels on digital subtracted images obtained by different dental subtraction programs. Paired periapical films were taken at the lower premolar and molar areas of the phantoms involving human mandible. The bite registration group used Rinn XCP equipment and bite registration material, based on polyvinyl siloxane, for standardization. The no bite registration group used only Rinn XCP equipment. The periapical film images were digitized at 1200 dpi resolution and 256 gray levels by a flat bed scanner with transparency unit. Dental digital subtraction programs used for this study were Subtractor (Biomedisys Co., Korea) and Emago (Oral Diagnostic Systems, The Netherlands). To measure the similarities between the subtracted images, the standard deviations of the gray levels were obtained using a histogram of subtracted images, which were then analyzed statistically. Subtracted images obtained by using the Emago program without manual selection of corresponding points showed the lowest standard deviation of gray levels (p<0.01). And the standard deviation of gray levels was lower in subtracted images in the group of a bite registration than in the group of no use of bite registration (p<0.01). Digital radiographic subtraction without manual selection of reference points was found to be a convenient and superior method.

  1. Towards sustainability assessment follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Morrison-Saunders, Angus, E-mail: a.morrison-saunders@murdoch.edu.au [Murdoch University (Australia); North-West University (South Africa); Pope, Jenny, E-mail: jenny@integral-sustainability.net [North-West University (South Africa); Integral Sustainability (Australia); Curtin University (Australia); Bond, Alan, E-mail: alan.bond@uea.ac.uk [North-West University (South Africa); University of East Anglia (United Kingdom); Retief, Francois, E-mail: francois.retief@nwu.ac.za [North-West University (South Africa)

    2014-02-15

    This paper conceptualises what sustainability assessment follow-up might entail for three models of sustainability assessment: EIA-driven integrated assessment, objectives-led integrated assessment and the contribution to sustainability model. The first two are characterised by proponent monitoring and evaluation of individual impacts and indicators while the latter takes a holistic view based around focused sustainability criteria relevant to the context. The implications of three sustainability challenges on follow-up are also examined: contested time horizons and value changes, trade-offs, and interdisciplinarity. We conclude that in order to meet these challenges some form of adaptive follow-up is necessary and that the contribution to sustainability approach is the best approach. -- Highlights: • We explore sustainability follow-up for three different sustainability models. • Long-time frames require adaptive follow-up and are a key follow-up challenge. • Other key challenges include interdisciplinarity, and trade-offs. • Sustainability follow-up should be a direction of travel and not an outcome. • Only the follow-up for contribution to sustainability model addresses sustainability challenges sufficiently.

  2. Follow-up utterances in QA dialogue

    NARCIS (Netherlands)

    van Schooten, B.W.; op den Akker, Hendrikus J.A.

    2006-01-01

    The processing of user follow-up utterances by a QA system is a topic which is still in its infant stages, but enjoys growing interest in the QA community. In this paper, we discuss the broader issues related to handling follow-up utterances in a real-life "information kiosk" setting. With help of a

  3. Towards sustainability assessment follow-up

    International Nuclear Information System (INIS)

    Morrison-Saunders, Angus; Pope, Jenny; Bond, Alan; Retief, Francois

    2014-01-01

    This paper conceptualises what sustainability assessment follow-up might entail for three models of sustainability assessment: EIA-driven integrated assessment, objectives-led integrated assessment and the contribution to sustainability model. The first two are characterised by proponent monitoring and evaluation of individual impacts and indicators while the latter takes a holistic view based around focused sustainability criteria relevant to the context. The implications of three sustainability challenges on follow-up are also examined: contested time horizons and value changes, trade-offs, and interdisciplinarity. We conclude that in order to meet these challenges some form of adaptive follow-up is necessary and that the contribution to sustainability approach is the best approach. -- Highlights: • We explore sustainability follow-up for three different sustainability models. • Long-time frames require adaptive follow-up and are a key follow-up challenge. • Other key challenges include interdisciplinarity, and trade-offs. • Sustainability follow-up should be a direction of travel and not an outcome. • Only the follow-up for contribution to sustainability model addresses sustainability challenges sufficiently

  4. Carbon dioxide digital subtraction angiography using a new gas management system; Digitale Subtraktionsangiographie mit Kohlendioxid unter Verwendung eines neuen Gasdosiersystems

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz-Rode, T.; Alzen, G.; Guenther, R.W. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum der RWTH Aachen (Germany)

    1997-07-01

    Purpose: The clinical evaluation of digital subtraction angiography with carbon dioxide using a newly developed low-tech CO{sub 2}-dosage- and injection system. Method and patients: The hand-held system (CO{sub 2} angio set) consists of a dosage chamber in connection with a special stopcock to apportion the gas. By optimising injection volume and pressure steady gas flow characteristics are approximated. A safety design prevents unintentional gas injection volume and pressure steady gas flow characteristics are approximated. A safety design prevents unintentional gas injection. CO{sub 2} arteriographies were performed on 185 patients. Main indications were renal insufficiency and a history of adverse reactions to iodinated contrast media. In patients with femoral connula access, catheterless reflux angiography was performed. Results: The injection system provided complete and coherent visualisation of the abdominal aorta, visceral, pelvic, and lower limb arteries via catheter (71 cases) or via femoral cannula using reflux technique (114 cases). Stenoses, occlusions, and collaterals were assessable. Employing the gas reflux over the aortic bifurcation bilateral run-off studies up to the calf trifurcation were performed via unilateral femoral cannula. Use of a dedicated stacking software improved image quality of distal femoral, popliteal and calf arteries. Conclusion: The CO{sub 2} management system allows adequate imaging of the arteries below the diaphragm. Ease and safety of use and low costs are advantageous. (orig.) [Deutsch] Ziel: Die klinische Erprobung der digitalen Subtraktionsangiographie mit Kohlendioxid unter Verwendung eines neuentwickelten, einfachen Gasdosier- und Injektionssystems. Methode und Patienten: Eine Dosierkammer mit einstellbarem Volumen in Verbindung mit einem Spezial-Hahn (CO{sub 2}-Angio-Set) portioniert das Gas. Durch Optimierung von Injektionsvolumen und -druck wurde eine konstante Ausstroemcharakteristik angenaehert. Das System wurde

  5. Comparison of C-arm Computed Tomography and Digital Subtraction Angiography in Patients with Chronic Thromboembolic Pulmonary Hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Hinrichs, Jan B., E-mail: hinrichs.jan@mh-hannover.de; Marquardt, Steffen, E-mail: marquardt.steffen@mh-hannover.de; Falck, Christian von, E-mail: falck.christian.von@mh-hannover.de [Hannover Medical School, Department for Diagnostic and Interventional Radiology, German Center for Lung Research (DZL) (Germany); Hoeper, Marius M., E-mail: hoeper.marius@mh-hannover.de; Olsson, Karen M., E-mail: olsson.karen@mh-hannover.de [Hannover Medical School, Clinic for Pneumology, German Center for Lung Research (DZL) (Germany); Wacker, Frank K., E-mail: wacker.frank@mh-hannover.de; Meyer, Bernhard C., E-mail: meyer.bernhard@mh-hannover.de [Hannover Medical School, Department for Diagnostic and Interventional Radiology, German Center for Lung Research (DZL) (Germany)

    2016-01-15

    PurposeTo assess the feasibility and diagnostic performance of contrast-enhanced, C-arm computed tomography (CACT) of the pulmonary arteries compared to digital subtraction angiography (DSA) in patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH).MaterialsFifty-two patients with CTEPH underwent ECG-gated DSA and contrast-enhanced CACT. Two readers (R1, R2) independently evaluated pulmonary artery segments and their sub-segmental branching using DSA and CACT for optimal image quality. Afterwards, the diagnostic findings, i.e., intraluminal filling defects, stenosis, and occlusion, were compared. Inter-modality and inter-observer agreement was calculated, and subsequently consensus reading was done and correlated to a reference standard representing the overall consensus of both modalities. Fisher’s exact test and Cohen’s Kappa were applied.ResultsA total of 1352 pulmonary segments were evaluated, of which 1255 (92.8 %) on DSA and 1256 (92.9 %) on CACT were rated to be fully diagnostic. The main causes of the non-diagnostic image quality were motion artifacts on CACT (R1:37, R2:78) and insufficient contrast enhancement on DSA (R1:59, R2:38). Inter-observer agreement was good for DSA (κ = 0.74) and CACT (κ = 0.75), while inter-modality agreement was moderate (R1: κ = 0.46, R2: κ = 0.47). Compared to the reference standard, the inter-modality agreement for CACT was excellent (κ = 0.96), whereas it was inferior for DSA (κ = 0.61) due to the higher number of abnormal consensus findings read as normal on DSA.ConclusionCACT of the pulmonary arteries is feasible and provides additional information to DSA. CACT has the potential to improve the diagnostic work-up of patients with CTEPH and may be particularly useful prior to surgical or interventional treatment.

  6. Follow-up in Childhood Functional Constipation

    DEFF Research Database (Denmark)

    Modin, Line; Walsted, Anne-Mette; Rittig, Charlotte Siggaard

    2016-01-01

    OBJECTIVES: Guidelines recommend close follow-up during treatment of childhood functional constipation. Only sparse evidence exists on how follow-up is best implemented. Our aim was to evaluate if follow-up by phone or self-management through web-based information improved treatment outcomes....... METHODS: In this randomized, controlled trial, conducted in secondary care, 235 children, aged 2-16 years, who fulfilled the Rome III criteria of childhood constipation, were assigned to one of three follow-up regimens: (I) control group (no scheduled contact), (II) phone group (2 scheduled phone contacts......: Improved self-management behavior caused by access to self-motivated web-based information induced faster short-term recovery during treatment of functional constipation. Patient empowerment rather than health care promoted follow-up might be a step towards more effective treatment for childhood...

  7. Audit Follow-up Tracking System (AFTS)

    Data.gov (United States)

    Office of Personnel Management — The Audit Follow-up Tracking System (AFTS) is used to track, monitor, and report on audits and open recommendations of the U.S. Office of Personnel Management (OPM)...

  8. A comparison between magnetic resonance angiography at 3 teslas (time-of-flight and contrast-enhanced and flat-panel digital subtraction angiography in the assessment of embolized brain aneurysms

    Directory of Open Access Journals (Sweden)

    Guilherme S. Nakiri

    2011-01-01

    Full Text Available PURPOSE: To compare the time-of-flight and contrast-enhanced- magnetic resonance angiography techniques in a 3 Tesla magnetic resonance unit with digital subtraction angiography with the latest flat-panel technology and 3D reconstruction in the evaluation of embolized cerebral aneurysms. INTRODUCTION: Many embolized aneurysms are subject to a recurrence of intra-aneurismal filling. Traditionally, imaging surveillance of coiled aneurysms has consisted of repeated digital subtraction angiography. However, this method has a small but significant risk of neurological complications, and many authors have advocated the use of noninvasive imaging methods for the surveillance of embolized aneurysms. METHODS: Forty-three aneurysms in 30 patients were studied consecutively between November 2009 and May 2010. Two interventional neuroradiologists rated the time-of-flight-magnetic resonance angiography, the contrast-enhanced-magnetic resonance angiography, and finally the digital subtraction angiography, first independently and then in consensus. The status of aneurysm occlusion was assessed according to the Raymond scale, which indicates the level of recanalization according to degrees: Class 1: excluded aneurysm; Class 2: persistence of a residual neck; Class 3: persistence of a residual aneurysm. The agreement among the analyses was assessed by applying the Kappa statistic. RESULTS: Inter-observer agreement was excellent for both methods (K = 0.93; 95 % CI: 0.84-1. Inter-technical agreement was almost perfect between time-of-flight-magnetic resonance angiography and digital subtraction angiography (K = 0.98; 95 % CI: 0.93-1 and between time-of-flight-magnetic resonance angiography and contrast-enhanced-magnetic resonance angiography (K = 0.98; 95% CI: 0.93-1. Disagreement occurred in only one case (2.3%, which was classified as Class I by time-of-flight-magnetic resonance angiography and Class II by digital subtraction angiography. The agreement between

  9. Utility of time-resolved three-dimensional magnetic resonance digital subtraction angiography without contrast material for assessment of intracranial dural arterio-venous fistula

    International Nuclear Information System (INIS)

    Hori, Masaaki; Aoki, Shigeki; Nakanishi, Atsushi; Shimoji, Keigo; Kamagata, Koji; Houshito, Haruyoshi; Kuwatsuru, Ryohei; Oishi, Hidenori; Arai, Hajime

    2011-01-01

    Background: Intracranial dural arteriovenous fistula (DAVF) is an arteriovenous shunting disease of the dura. Magnetic resonance angiography (MRA) is expected to be a safer alternative method in evaluation of DAVF, compared with invasive intra-arterial digital subtraction angiography (IADSA). Purpose: To evaluate the diagnostic use of time-spatial labeling inversion pulse (Time-SLIP) three-dimensional (3D) magnetic resonance digital subtraction angiography (MRDSA) without contrast material in six patients with DAVF. Material and Methods: Images for 3D time-of-flight MRA, which has been a valuable tool for the diagnosis of DAVF but provide little or less hemodynamic information, and Time-SLIP 3D MRDSA, were acquired for each patient. The presence, side, and grade of the disease were evaluated according to IADSA. Results: In all patients, the presence and side of the DAVF were correctly identified by both 3D time-of-flight MRA and Time-SLIP 3D MRDSA. Cortical reflux present in a patient with a grade 2b DAVF was not detected by Time-SLIP 3D MRDSA, when compared with IADSA findings. Conclusion: Time-SLIP 3D MRDSA provides hemodynamic information without contrast material and is a useful complementary tool for diagnosis of DAVF

  10. Rectal neoplasms. Postoperative follow-up

    International Nuclear Information System (INIS)

    Galano Urgelles, Rolando; Rodriguez Fernandez, Zenen; Casaus Prieto, Arbelio

    1997-01-01

    A study of 31 patients operated on for rectal neoplasms between September, 1989 and September, 1995 in SantiAug de Cuba was performed. Patients Webre followed-up during this period for the purpose of the study. There was a frank predominance of males and ages between 45 and 64, of the stage II and the groups BI and BII according to Dukes' classification. Most patients received 5-fluoracil, without tumor relapses. The current survival rate of the series was 76 % at the end of the investigation. It is recommended that all patients operated on for this segment be followed-up after the operation; to continue with cytostatic treatment using 5-fluoracil, and to emphasize the importance of the use of tumor markers during the follow-up, in addition to transrectal ultrasound, as well as to make an early diagnosis through mass screening methods

  11. Follow-up after rectal cancer

    DEFF Research Database (Denmark)

    Hovdenak Jakobsen, Ida; Juul, Therese; Bernstein, Inge

    2017-01-01

    BACKGROUND: The main treatment for non-metastatic rectal cancer (RC) is surgical resection. Late adverse effects that are highly prevalent and negatively impact patients' symptom burden and quality of life are: bowel-, urological and sexual dysfunctions; psychological distress; fear of recurrence....... As a consequence, the randomized controlled trial Follow-up after Rectal Cancer (FURCA) has been launched, testing the effect of a new patient-led, follow-up program. The aim of this paper is to describe the methodology used in the FURCA study and to report results from the development of the patient-led, follow......, or a control group following the current follow-up program with routine medicals. The primary outcomes are symptom burden and quality of life, measured by the Functional Assessment of Cancer Therapy - Colorectal (FACT-C) questionnaire. Other outcome and demographic data are collected as patient...

  12. MR angiography in the follow-up of coiled cerebral aneurysms after treatment with Guglielmi detachable coils

    International Nuclear Information System (INIS)

    Nome, T.; Bakke, S. J.; Nakstad, P. H.

    2002-01-01

    Purpose: Intra-arterial digital subtraction angiography (DSA) has been considered the gold standard examination in the follow-up of patients treated with Guglielmi detachable coils (GDCs). However, DSA is an invasive and expensive investigation and results in exposure to ionising radiation to both patient and operator. The aim of this study was to compare MR angiography (MRA) with DSA with regard to patency of the occlusion of aneurysms following GDC treatment. Material and Methods: We performed 75 MRA and DSA examinations on 51 patients treated with GDCs. The examinations were performed 3-36 months after embolisation and the interval between MRA and DSA was less than 1 week. Hard copies of both studies were interpreted retrospectively and independently for residual flow within the aneurysm, residual aneurysmal neck, and parent and branch vessel flow. Results: Patency status of parent and branch vessel flow was correctly identified with MRA in all patients except 1. The sensitivity of MRA in revealing residual flow within the aneurysm was 97%. The specificity in ruling out residual flow within the aneurysm was 91%. Conclusion: MRA may replace DSA in the long-term follow-up of coiled cerebral aneurysms. The initial follow-up examination should, however, include both modalities

  13. The Kepler follow-up observation program

    DEFF Research Database (Denmark)

    Gautier...[], T.N.; Batalha, N.M.; Borucki, W. J.

    2010-01-01

    The Kepler Mission was launched on March 6, 2009 to perform a photometric survey of more than 100,000 dwarf stars to search for terrestrial-size planets with the transit technique. Follow-up observations of planetary candidates identified by detection of transit-like events are needed both...

  14. A novel approach to background subtraction in contrast-enhanced dual-energy digital mammography with commercially available mammography devices: Polychromaticity correction

    Energy Technology Data Exchange (ETDEWEB)

    Contillo, Adriano, E-mail: contillo@fe.infn.it; Di Domenico, Giovanni; Cardarelli, Paolo; Gambaccini, Mauro; Taibi, Angelo [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, Ferrara I-44122 (Italy)

    2015-11-15

    Purpose: Contrast-enhanced digital mammography is an image subtraction technique that is able to improve the detectability of lesions in dense breasts. One of the main sources of error, when the technique is performed by means of commercial mammography devices, is represented by the intrinsic polychromaticity of the x-ray beams. The aim of the work is to propose an iterative procedure, which only assumes the knowledge of a small set of universal quantities, to take into account the polychromaticity and correct the subtraction results accordingly. Methods: In order to verify the procedure, it has been applied to an analytical simulation of a target containing a contrast medium and to actual radiographs of a breast phantom containing cavities filled with a solution of the same medium. Results: The reconstructed densities of contrast medium were compared, showing very good agreement between the theoretical predictions and the experimental results already after the first iteration. Furthermore, the convergence of the iterative procedure was studied, showing that only a small number of iterations is necessary to reach limiting values. Conclusions: The proposed procedure represents an efficient solution to the polychromaticity issue, qualifying therefore as a viable alternative to inverse-map functions.

  15. Follow-up of colorectal cancer patients: quality of life and attitudes towards follow-up

    NARCIS (Netherlands)

    Stiggelbout, A. M.; de Haes, J. C.; Vree, R.; van de Velde, C. J.; Bruijninckx, C. M.; van Groningen, K.; Kievit, J.

    1997-01-01

    The aims of our study were to assess the effect of follow-up on the quality of life of colorectal cancer patients and to assess the attitudes of patients towards follow-up as a function of patient characteristics. Patients who had been treated with curative intent were selected from four types of

  16. Tests of variable-band multilayers designed for investigating optimal signal-to-noise vs artifact signal ratios in Dual-Energy Digital Subtraction Angiography (DDSA) imaging systems

    International Nuclear Information System (INIS)

    Boyers, D.; Ho, A.; Li, Q.; Piestrup, M.; Rice, M.; Tatchyn, R.

    1993-08-01

    In recent work, various design techniques were applied to investigate the feasibility of controlling the bandwidth and bandshape profiles of tungsten/boron-carbon (W/B 4 C) and tungsten/silicon (W/Si) multilayers for optimizing their performance in synchrotron radiation based angiographical imaging systems at 33 keV. Varied parameters included alternative spacing geometries, material thickness ratios, and numbers of layer pairs. Planar optics with nominal design reflectivities of 30%--94% and bandwidths ranging from 0.6%--10% were designed at the Stanford Radiation Laboratory, fabricated by the Ovonic Synthetic Materials Company, and characterized on Beam Line 4-3 at the Stanford Synchrotron Radiation Laboratory, in this paper we report selected results of these tests and review the possible use of the multilayers for determining optimal signal to noise vs. artifact signal ratios in practical Dual-Energy Digital Subtraction Angiography systems

  17. [Clinical values of hemodynamics assessment by parametric color coding of digital subtraction angiography before and after endovascular therapy for critical limb ischaemia].

    Science.gov (United States)

    Su, Haobo; Lou, Wensheng; Gu, Jianping

    2015-10-06

    To investigate the feasibility of parametric color coding of digital subtraction angiography (Syngo iFlow) for hemodynamics assessment in patients with critical limb ischemia in pre- and post-endovascular therapy. To explore the correlation between Syngo iFlow and the conventional techniques. from January 2013 to December 2014, Clinical data of 21 patients with TASC II type B and type C femoropopliteal arteriosclerotic occlusive disease who were treated by percutaneous transluminal angioplasty and/or primary stent implantation in Nanjing first hospital were analyzed retrospectively. Of these patients there were 10 males and 11 females with an average age of (72±6) years (range from 58-85 years). The treatment efficacy was assessed by the variation of a series of clinical symptoms indexes (such as pain score, cold sensation score and intermittent claudication score), ankle braehial index (ABI) and transcutaneous oxygen pressure (TcPO2). Angiography was performed with the same protocol before and after treatment and parametric color coding of digital subtraction angiography was created by Syngo iFlow software on a dedicated workstation. The time to peak (TTP) of artery and tissue perfusion selected at the same regions of foot and ankle were measured and analyzed to evaluate the improvement of microcirculation and hemodynamics of the ischemic limb. The correlations between Syngo iFlow and the traditional clinical evaluation methods were explored using the Spearman rank correlation test. All patients (21 limbs) underwent successful endovaseular therapy. The mean pain score, cold sensation score, intermittent claudication score, ABI and TcPO2 before treatment were (0.48±0.68), (2.71±0.72), (2.86±0.85), ABI (0.33±0.07), TcPO2 (26.83±3.41) mmHg. While 1 week after treatment all above indicators were (2.57±0.93), (0.33±0.48), (0.90±0.54), (0.69±0.11), TcPO2 (53.75±3.60) mmHg respectively. There were significant statistical differences between pre- and post

  18. Digital subtraction angiography (DSA) of aortocoronary bypass grafts in the early postoperative phase with peripheral-venous contrast medium injection

    International Nuclear Information System (INIS)

    Tuengerthal, S.; Lang, J.; Donhoeffner, A.

    1985-01-01

    Using a fully digitalised subtraction unit, aortocoronary bypass grafts can be visualised in the early postoperative phase by means of peripheral venous contrast medium injection (57 out of a total of 60 cases). In more than one-half of the cases (31 out of a total of 60), it is possible to outline sharply the bypass grafts from the beginning to their entry into the bridged-over coronary artery, in such a manner that any loops, kinks, stenoses or reduced flow rates can be recognised. This examination is not considered to be an invasive one by the patient, and the cardiosurgeon can welcome it as a valuable additional means of controlling and assessing the results of surgery. (orig.) [de

  19. Feasibility of magnetic resonance angiography (MRA) follow-up as the primary imaging modality after coiling of intracranial aneurysms

    International Nuclear Information System (INIS)

    Bakker, Nicolaas A.; Metzemaekers, Jan D. M.; Dijk, J. Marc C. van; Mooij, Jan Jakob A.; Groen, Rob J. M.; Westerlaan, Henriette E.; Eshghi, Omid S.

    2010-01-01

    Background: Digital subtraction angiography (DSA) is still regarded as the gold standard for detecting residual flow in treated aneurysms. Recent reports have also shown excellent results from magnetic resonance angiography (MRA) imaging. This is an important observation, since DSA is associated with a risk of medical complications, is time consuming, and is more expensive. Purpose: To determine whether MRA could replace conventional DSA and serve as the primary postinterventional imaging modality in patients with coiled intracranial aneurysms. Material and Methods: We studied a prospectively enrolled cohort of 190 patients treated endovascularly for a first-ruptured and/or unruptured intracranial aneurysm between January 2004 and December 2008. The imaging protocol included a 1.5T time-of-flight (TOF) MRA and a DSA at 3 months (on the same day) and, depending on comparability, a 1.5T TOF-MRA or DSA 1 year after treatment. All images were evaluated by a multidisciplinary panel. Results: In 141/190 patients, both an MRA and DSA were performed after 3-month follow-up. In 2/141 patients (1.4%), (small) neck remnants gave false-negative MRA results. In one patient (0.7%), this led to additional neurosurgical clipping of the aneurysm. In 25/141 patients, future follow-up (>3 months) consisted of DSA because of various reasons. In 24/25 of these patients, primary MRA images alone would invariably have led to additional DSA imaging. Conclusion: The present study shows that 1.5T TOF-MRA is a feasible primary follow-up modality after coiling of intracranial aneurysms. Given our data, we now suggest that, in every patient with a coiled intracranial aneurysm, the first follow-up, 3 months after coiling, should be an MRA study. Only when this MRA is inconclusive (e.g., because of coil artifacts), or in the case of suspicion of recanalization, should DSA be performed additionally

  20. A computational fluid dynamics (CFD) study of WEB-treated aneurysms: Can CFD predict WEB "compression" during follow-up?

    Science.gov (United States)

    Caroff, Jildaz; Mihalea, Cristian; Da Ros, Valerio; Yagi, Takanobu; Iacobucci, Marta; Ikka, Léon; Moret, Jacques; Spelle, Laurent

    2017-07-01

    Recent reports have revealed a worsening of aneurysm occlusion between WEB treatment baseline and angiographic follow-up due to "compression" of the device. We utilized computational fluid dynamics (CFD) in order to determine whether the underlying mechanism of this worsening is flow related. We included data from all consecutive patients treated in our institution with a WEB for unruptured aneurysms located either at the middle cerebral artery or basilar tip. The CFD study was performed using pre-operative 3D rotational angiography. From digital subtraction follow-up angiographies patients were dichotomized into two groups: one with WEB "compression" and one without. We performed statistical analyses to determine a potential correlation between WEB compression and CFD inflow ratio. Between July 2012 and June 2015, a total of 22 unruptured middle cerebral artery or basilar tip aneurysms were treated with a WEB device in our department. Three patients were excluded from the analysis and the mean follow-up period was 17months. Eleven WEBs presented "compression" during follow-up. Interestingly, device "compression" was statistically correlated to the CFD inflow ratio (P=0.018), although not to aneurysm volume, aspect ratio or neck size. The mechanisms underlying the worsening of aneurysm occlusion in WEB-treated patients due to device compression are most likely complex as well as multifactorial. However, it is apparent from our pilot study that a high arterial inflow is, at least, partially involved. Further theoretical and animal research studies are needed to increase our understanding of this phenomenon. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  1. Exact measurement of vascular lumina in digital subtraction arteriography (DSA) during stent implantations and percutaneous transluminal angioplasty (PTA)

    Energy Technology Data Exchange (ETDEWEB)

    Pfluger, T [Dept. of Radiology, Univ. of Munich (Germany); Kueffer, G [Dept. of Radiology, Univ. of Munich (Germany); Hahn, D [Dept. of Radiology, Univ. of Munich (Germany)

    1992-06-01

    There are inherent difficulties in using high-resolution DSA in interventional radiology for measuring vascular luminal diameter since enlargement ratios are not constant. We present a system that permits accurate determination of vascular lumen diameters by means of a special angiographic catheter with predefined marking points. The accuracy of this measuring method was explored in tests using phantoms. In vivo practicability of the method was proved in PTA and stent implantations in 39 patients. This method with a maximum error of measurement of 5% appears to provide adequate safety in the choice of suitable dilating balloons and stents in interventional vascular procedures. In follow-up, it permits the accurate measurement of neo-intimal thickness. (orig.)

  2. Evaluation of anastomosis between intrahepatic or extrahepatic vessels by intra-arterial digital subtraction angiography using carbon dioxide

    International Nuclear Information System (INIS)

    Miyazono, Nobuaki; Inoue, Hiroki; Ueno, Kazuto; Nishida, Hirotoshi; Kanetsuki, Ichirou; Miyake, Satoshi; Nakajo, Masayuki

    1995-01-01

    Carbon dioxide (CO 2 ) intra-arterial subtraction angiography (IADSA) was performed in 31 patients with various hepatobiliary disease. The injection sites of CO 2 were proper hepatic artery (10/31; group A), segmental hepatic artery (18/31; group B), and peripheral inferior phrenic artery (3/31; group C), respectively. In group A, only the third order branches of the portal venous system were visualized anterogradely in 8 of 10 patients. In group B, the microcatheter was placed coaxially through a 5 French guiding catheter at the main arterial supply of the tumor in 7 patients and at the peripheral segmental branch of the hepatic artery in 11 patients. The portal venous system was visualized retrogradely in all of the patients regardless of the injection site. The injected CO 2 may flow back into the portal vein through the anastmosis known as the peribiliary or periportal plexus. In group C, not only the portal vein but also the pulmonary artery or pericardial vein were visualized by this method. CO 2 -IADSA was useful to image the minute communications between the various vessels, which have been not hitherto visualized by iodinated contrast medium. (author)

  3. Evaluation of anastomosis between intrahepatic or extrahepatic vessels by intra-arterial digital subtraction angiography using carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Miyazono, Nobuaki; Inoue, Hiroki; Ueno, Kazuto; Nishida, Hirotoshi; Kanetsuki, Ichirou; Miyake, Satoshi; Nakajo, Masayuki [Kagoshima Univ. (Japan). Faculty of Medicine

    1995-04-01

    Carbon dioxide (CO{sub 2}) intra-arterial subtraction angiography (IADSA) was performed in 31 patients with various hepatobiliary disease. The injection sites of CO{sub 2} were proper hepatic artery (10/31; group A), segmental hepatic artery (18/31; group B), and peripheral inferior phrenic artery (3/31; group C), respectively. In group A, only the third order branches of the portal venous system were visualized anterogradely in 8 of 10 patients. In group B, the microcatheter was placed coaxially through a 5 French guiding catheter at the main arterial supply of the tumor in 7 patients and at the peripheral segmental branch of the hepatic artery in 11 patients. The portal venous system was visualized retrogradely in all of the patients regardless of the injection site. The injected CO{sub 2} may flow back into the portal vein through the anastmosis known as the peribiliary or periportal plexus. In group C, not only the portal vein but also the pulmonary artery or pericardial vein were visualized by this method. CO{sub 2}-IADSA was useful to image the minute communications between the various vessels, which have been not hitherto visualized by iodinated contrast medium. (author).

  4. Spectroscopic follow up of Kepler planet candidates

    DEFF Research Database (Denmark)

    Latham..[], D. W.; Cochran, W. D.; Marcy, G.W.

    2010-01-01

    Spectroscopic follow-up observations play a crucial role in the confirmation and characterization of transiting planet candidates identified by Kepler. The most challenging part of this work is the determination of radial velocities with a precision approaching 1 m/s in order to derive masses from...... spectroscopic orbits. The most precious resource for this work is HIRES on Keck I, to be joined by HARPS-North on the William Herschel Telescope when that new spectrometer comes on line in two years. Because a large fraction of the planet candidates are in fact stellar systems involving eclipsing stars...... and not planets, our strategy is to start with reconnaissance spectroscopy using smaller telescopes, to sort out and reject as many of the false positives as possible before going to Keck. During the first Kepler observing season in 2009, more than 100 nights of telescope time were allocated for this work, using...

  5. Pituitary dysfunction from an unruptured ophthalmic internal carotid artery aneurysm with improved 2-year follow-up results: A case report

    Directory of Open Access Journals (Sweden)

    Qi Meng

    2018-04-01

    Full Text Available Internal carotid artery (ICA supraclinoid segment aneurysms extending into the sellar region and leading to pituitary dysfunction are a rare occurrence. To date, long-term follow up of pituitary function 2 years post-treatment has never been reported. Herein, we present a case of pituitary dysfunction due to an unruptured ophthalmic segment internal carotid artery aneurysm and report improved 2-year follow-up results. A 76-year-old male presented with disturbed consciousness due to hyponatremia, which was caused by hypoadrenocorticism resulting from pituitary dysfunction complicated by hypogonadism and hypothyroidism. Computed tomography angiography revealed an intracranial aneurysm of the ophthalmic segment of the right ICA with an intrasellar extension. Thus, digital subtraction angiography and coil embolization were performed, followed by hormone replacement therapy. A 2-year follow-up revealed a partial improvement in the pituitary function, including complete restoration of thyroid-stimulating hormone level and other thyroid hormones levels, and partial restoration of testosterone levels, followed by discontinuation of thyroid hormone replacement therapy. However, the mechanisms of such pituitary dysfunction and the effects of various treatments, including clipping and coiling, on different hormones of pituitary function recovery remain unclear. A long-term follow-up of >2 years may elucidate the pituitary function recovery post-treatment and provide a medication adjustment for hormone replacement therapy.

  6. Pituitary Dysfunction from an Unruptured Ophthalmic Internal Carotid Artery Aneurysm with Improved 2-year Follow-up Results: A Case Report.

    Science.gov (United States)

    Qi, Meng; Ye, Ming; Li, Meng; Zhang, Peng

    2018-01-01

    Internal carotid artery (ICA) supraclinoid segment aneurysms extending into the sellar region and leading to pituitary dysfunction are a rare occurrence. To date, long-term follow up of pituitary function 2 years post-treatment has never been reported. Herein, we present a case of pituitary dysfunction due to an unruptured ophthalmic segment internal carotid artery aneurysm and report improved 2-year follow-up results. A 76-year-old male presented with disturbed consciousness due to hyponatremia, which was caused by hypoadrenocorticism resulting from pituitary dysfunction complicated by hypogonadism and hypothyroidism. Computed tomography angiography revealed an intracranial aneurysm of the ophthalmic segment of the right ICA with an intrasellar extension. Thus, digital subtraction angiography and coil embolization were performed, followed by hormone replacement therapy. A 2-year follow-up revealed a partial improvement in the pituitary function, including complete restoration of thyroid-stimulating hormone level and other thyroid hormones levels, and partial restoration of testosterone levels, followed by discontinuation of thyroid hormone replacement therapy. However, the mechanisms of such pituitary dysfunction and the effects of various treatments, including clipping and coiling, on different hormones of pituitary function recovery remain unclear. A long-term follow-up of >2 years may elucidate the pituitary function recovery post-treatment and provide a medication adjustment for hormone replacement therapy.

  7. Real-time out-of-plane artifact subtraction tomosynthesis imaging using prior CT for scanning beam digital x-ray system

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng, E-mail: mengwu@stanford.edu [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2014-11-01

    Purpose: The scanning beam digital x-ray system (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real-time tomosynthesis in multiple planes. This system could be used for image guidance during lung nodule biopsy. However, the reconstructed images suffer from strong out-of-plane artifact due to the small tomographic angle of the system. Methods: The authors propose an out-of-plane artifact subtraction tomosynthesis (OPAST) algorithm that utilizes a prior CT volume to augment the run-time image processing. A blur-and-add (BAA) analytical model, derived from the project-to-backproject physical model, permits the generation of tomosynthesis images that are a good approximation to the shift-and-add (SAA) reconstructed image. A computationally practical algorithm is proposed to simulate images and out-of-plane artifacts from patient-specific prior CT volumes using the BAA model. A 3D image registration algorithm to align the simulated and reconstructed images is described. The accuracy of the BAA analytical model and the OPAST algorithm was evaluated using three lung cancer patients’ CT data. The OPAST and image registration algorithms were also tested with added nonrigid respiratory motions. Results: Image similarity measurements, including the correlation coefficient, mean squared error, and structural similarity index, indicated that the BAA model is very accurate in simulating the SAA images from the prior CT for the SBDX system. The shift-variant effect of the BAA model can be ignored when the shifts between SBDX images and CT volumes are within ±10 mm in the x and y directions. The nodule visibility and depth resolution are improved by subtracting simulated artifacts from the reconstructions. The image registration and OPAST are robust in the presence of added respiratory motions. The dominant artifacts in the subtraction images are caused by the mismatches between the real object and the prior CT

  8. Intracranial contrast transit times on digital subtraction angiography decrease more in patients with delayed intraparenchymal hemorrhage after Pipeline.

    Science.gov (United States)

    Brunozzi, Denise; Shakur, Sophia F; Charbel, Fady T; Alaraj, Ali

    2018-04-01

    Background Pipeline embolization devices (PEDs) are used for endovascular treatment of cerebral aneurysms but can be associated with delayed ipsilateral intraparenchymal hemorrhage (DIPH). Changes in intracranial hemodynamics after PED are poorly understood. Objective Here, we assess hemodynamic changes after PED in patients and compare these changes in patients with and without DIPH (DIPH+ and DIPH-). Methods Records of patients with distal internal carotid artery (ICA) aneurysms treated with PED at our institution between 2012 and 2017 were retrospectively reviewed. Regions of interest were selected proximally to PED over the cavernous ICA and distally over the middle cerebral artery (MCA), and then transit times were determined using syngo iFlow software (Siemens). Ratio of MCA to ICA transit time was compared before, after treatment, and at follow-up. Ratios were also compared between DIPH+ and DIPH- subgroups. Correlations between aneurysm size, age, and ratios were investigated. Results Fifty-three patients were included. The ratio of MCA to ICA transit time decreased significantly after PED deployment (1.13 vs. 1.22, p transit time decreases following PED treatment and decreases more in patients with DIPH. These contrast transit time changes can be detected in real time immediately after PED deployment.

  9. Screening for cervical cancer among HIV-positive and HIV-negative women in Cameroon using simultaneous co-testing with careHPV DNA testing and visual inspection enhanced by digital cervicography: Findings of initial screening and one-year follow-up.

    Science.gov (United States)

    Cholli, Preetam; Bradford, Leslie; Manga, Simon; Nulah, Kathleen; Kiyang, Edith; Manjuh, Florence; DeGregorio, Geneva; Ogembo, Rebecca K; Orock, Enow; Liu, Yuxin; Wamai, Richard G; Sheldon, Lisa Kennedy; Gona, Philimon N; Sando, Zacharie; Welty, Thomas; Welty, Edith; Ogembo, Javier Gordon

    2018-01-01

    The World Health Organization (WHO)'s cervical cancer screening guidelines for limited-resource settings recommend sequential screening followed by same-day treatment under a "screen-and-treat" approach. We aimed to (1) assess feasibility and clinical outcomes of screening HIV-positive and HIV-negative Cameroonian women by pairing visual inspection with acetic acid and Lugol's iodine enhanced by digital cervicography (VIA/VILI-DC) with careHPV, a high-risk human papillomavirus (HR-HPV) nucleic acid test designed for low-resource settings; and (2) determine persistence of HR-HPV infection after one-year follow-up to inform optimal screening, treatment, and follow-up algorithms. We co-tested 913 previously unscreened women aged ≥30years and applied WHO-recommended treatment for all VIA/VILI-DC-positive women. Baseline prevalence of HR-HPV and HIV were 24% and 42%, respectively. On initial screen, 44 (5%) women were VIA/VILI-DC-positive, of whom 22 had HR-HPV infection, indicating 50% of women screened false-positive and would have been triaged for unnecessary same-day treatment. VIA/VILI-DC-positive women with HIV infection were three times more likely to be HR-HPV-positive than HIV-negative women (65% vs. 20%). All women positive for either VIA/VILI-DC or HR-HPV (n=245) were invited for repeat co-testing after one year, of which 136 (56%) returned for follow-up. Of 122 women who were HR-HPV-positive on initial screen, 60 (49%) re-tested negative, of whom 6 had received treatment after initial screen, indicating that 44% of initially HR-HPV-positive women spontaneously cleared infection after one year without treatment. Women with HIV were more likely to remain HR-HPV-positive on follow-up than HIV-negative women (61% vs. 22%, p<0.001). Treatment was offered to all VIA/VILI-DC positive women on initial screen, and to all women screening VIA/VILI-DC or HR-HPV positive on follow-up. We found careHPV co-testing with VIA/VILI-DC to be feasible and valuable in

  10. Morbidity follow-up feasibility study

    International Nuclear Information System (INIS)

    Carpenter, M.

    1988-02-01

    The report reviews the available sources of data within Canada for undertaking morbidity follow-up studies to both supplement and complement studies using Canadian mortality data. Such studies would permit earlier detection and more sensitive measures of differences in risk for exposures to radiation and allow timely measures to be taken to minimize any occupational and environmental health risk to radiation workers. The technical feasibility of using these sources was reviewed using the criteria of adequate personal identifying information, automation of data records, file size and the accuracy of the morbidity diagnosis information. At the present time certain of the provincial cancer registry files meet these criteria best. A work plan was prepared suggesting a morbidity pilot study to clarify the role of occupational factors in the incidence of cancer among radiation workers using the Alberta Cancer Registry file and the National Dose Registry (NDR) file of radiation workers. For the longer term a full cohort study using the National Cancer Incidence Reporting System (NCIRS) and the NDR workers as the study population would provide information on all radiation workers on a national basis. A work plan was prepared and some initial format conversion of historical data was undertaken to begin developing the NCIRS into a data base suitable for long-term health studies

  11. Therapeutic abortion follow-up study.

    Science.gov (United States)

    Margolis, A J; Davison, L A; Hanson, K H; Loos, S A; Mikkelsen, C M

    1971-05-15

    To determine the long-range psychological effects of therapeutic abortion, 50 women (aged from 13-44 years), who were granted abortions between 1967 and 1968 Because of possible impairment of mental and/or physical health, were analyzed by use of demographic questionnaires, psychological tests, and interviews. Testing revealed that 44 women had psychiatric problems at time of abortion. 43 patients were followed for 3-6 months. The follow-up interviews revealed that 29 patients reacted positively after abortion, 10 reported no significant change and 4 reacted negatively. 37 would definitely repeat the abortion. Women under 21 years of age felt substantially more ambivalent and guilty than older patients. A study of 36 paired pre- and post-abortion profiles showed that 15 initially abnormal tests had become normal. There was a significant increase in contraceptive use among the patients after the abortion, but 4 again became pregnant and 8 were apparently without consistent contraception. It is concluded that the abortions were therapeutic, but physicians are encouraged to be aware of psychological problems in abortion cases. Strong psychological and contraceptive counselling should be exercised.

  12. Colon neoplasms. Postoperative follow-up

    International Nuclear Information System (INIS)

    Galano Urgelles, Rolando; Rodriguez Fernandez, Zenen; Casaus Prieto, Arbelio

    1997-01-01

    A longitudinal and prospective study of 69 patients operated on for colon cancer was carried out during 6 years. Patients Webre folloWebd-up for the purpose of the study. The analysis evidenced that the most frequent age group ranged betWeben 65 and 74 years and that there was a predominance of females, as Webll as of stages II and III b and groups BI and BII according to Dukes' classification. Certain relapses resulting in re operations Webre detected. 5-fluoracil was used as a therapeutic agent, while the highest survival rate was attained in patients presenting with tumors in 0, I, II, and III a stages from groups A, BI, and CI of Dukes, or in those who complied with the cytostatic treatment. Survival outcomes Webre higher than the ones reported. Recommendations include to encourage mass screening in those risk groups at primary care level in order to detect early the entity, and thus improve the surgical outcomes and the results of postoperative follow-up

  13. Follow-up radiological surveillance, Marshall Islands

    International Nuclear Information System (INIS)

    Greenhouse, N.A.

    1978-01-01

    The political approvals have been given for the return of Bikini and Enewetak Atolls to their original inhabitants. These two regions, which comprised the Pacific Nuclear Testing Areas from 1946 to 1958, are now being repopulated by their original inhabitants and their families. Recent assessments of internal and external exposure pathways at Bikini and Enewetak have indicated that doses and dose commitments in excess of current radiation protection guidelines are possible or even likely for persons living in these areas. Rongelap and Utirik Atolls, which were downwind of the 1954 Bravo event, also received significant fallout; potential radiological problems exist in these areas as well. In view of this prospect, follow-up environmental monitoring and personnel monitoring programs are being established to maintain our cognizance of radiological conditions, and to make corrective action where necessary. The unexpected finding of detectable amounts (above background) of plutonium in the urine of individuals at Bikini and Rongelap Atolls also raises the possibility of radiological problems in the long term from environmentally-derived plutonium via pathways which are not completely understood. This finding adds further impetus to the surveillance programs for an area where real radiological concerns for the general public are already known to exist. The continuing environmental and personnel monitoring programs which this paper describes are a necessary part of the BNL radiological safety program in the Marshall Islands, which is designed to do the following: (1) elucidate the internal exposure pathways; (2) define the external radiation environment; (3) assess the doses and dose commitments from radioactivity in the environment; (4) provide the feedback necessary to improve existing predictive modelling of radiological trends; and (5) suggest actions which will minimize doses via the more significant pathways. (author)

  14. The value of magnetic resonance imaging for the detection of the bleeding source in non-traumatic intracerebral haemorrhages: a comparison with conventional digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lummel, Nina; Lutz, Juergen; Brueckmann, Hartmut; Linn, Jennifer [University of Munich, Department of Neuroradiology, Munich (Germany)

    2012-07-15

    Conventional digital subtraction angiography (DSA) is currently regarded as the gold standard in detecting underlying vascular pathologies in patients with intracerebral haemorrhages (ICH). However, the use of magnetic resonance imaging (MRI) in the diagnostic workup of ICHs has considerably increased in recent years. Our aim was to evaluate the diagnostic accuracy and yield of MRI for the detection of the underlying aetiology in ICH patients. Sixty-seven consecutive patients with an acute ICH who underwent MRI (including magnetic resonance angiography (MRA) and DSA during their diagnostic workup) were included in the study. Magnetic resonance images were retrospectively analysed by two independent neuroradiologists to determine the localisation and cause of the ICH. DSA was used as a reference standard. In seven patients (10.4%), a DSA-positive vascular aetiology was present (one aneurysm, four arteriovenous malformations, one dural arteriovenous fistula and one vasculitis). All of these cases were correctly diagnosed by both readers on MRI. In addition, MRI revealed the following probable bleeding causes in 39 of the 60 DSA-negative patients: cerebral amyloid angiopathy (17), cavernoma (9), arterial hypertension (8), haemorrhagic transformation of an ischaemic infarction (3) and malignant brain tumour with secondary ICH (2). Performing MRI with MRA proved to be an accurate diagnostic tool in detecting vascular malformations in patients with ICH. In addition, MRI provided valuable information regarding DSA-negative ICH causes, and thus had a high diagnostic yield in ICH patients. (orig.)

  15. Mechanism of the re-buildup phenomenon in moyamoya disease; Analysis of local cerebral hemodynamics with intra-arterial digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Touho, Hajime; Karasawa, Jun; Shishido, Hisashi; Morisako, Toshitaka; Yamada, Keisuke; Nagai, Shigeki; Shibamoto, Kenji [Osaka Neurological Institute, Osaka (Japan)

    1990-10-01

    The authors investigated the mechanism of the re-buildup phenomenon on electroencephalogram in 14 patients of moyamoya disease with superficial temporal artery-middle cerebral artery anastomosis. Visualization of the lateral view of the common carotid angiography was performed with intra-arterial digital subtraction angiography (IA-DSA), using a 4/sec x 3 sec + 2/sec x 5 sec + 1/sec x 5 sec film sequence. The catheter tip was inserted into C5/6 level and 250 mgl/ml of iopamidol was used as the contrast agent; 6 ml in total was injected over 1.5 seconds. Circulation times of the common carotid artery (C{sub 3} portion)-ascending parietal vein ({delta}TTP{sub s}) and common carotid artery-internal cerebral vein ({delta}TTP{sub D}) were measured before hyperventilation (HV), immediately after HV, and 3 minutes after HV during pre- and postoperative periods. {delta}TTP{sub D} in the preoperative period was prolonged by HV and was normalized at 3 minutes after HV but {delta}TTP{sub S} were prolonged immediately after and 3 minutes after HV. In the postoperative period, however, these values did not change significantly immediately after and 3 minutes after HV. These findings indicate that delayed cerebral blood flow response to HV is a pathogenetic factor of the re-buildup phenomenon in moyamoya disease. (author).

  16. Detection of the origin of the cystic artery during transcatheter arterial embolization of hepatocellular carcinomas. Comparison of cone beam CT and digital subtraction angiography

    International Nuclear Information System (INIS)

    Hashizume, Takashi; Honda, Minoru; Seino, Noritaka; Gokan, Takehiko; Hashimoto, Toshi

    2009-01-01

    In this study, we retrospectively compared the usefulness of cone beam CT (CBCT) with that of digital subtraction angiography (DSA) in the identification of the origin of the cystic artery during arterial embolization for hepatocellular carcinoma. Subjects were sixty-four patients who underwent transcatheter arterial embolization (TAE) for hepatocellular carcinoma, in whom both CBCT and DSA were performed. Two radiologists independently examined CBCT and DSA images, and attempted to identify the origin of the cystic artery in each image. For DSA, en face views were reviewed on the monitor. For CBCT, 5 mm thick horizontal sections were generated using Workstation software, and the MPR (multi-planner reconstruction) method was used for coronary sections. These were then investigated with OsiriX. Of the sixty-four patients, the cystic arterial origin could be identified using DSA in 21 (32.8%) and CBCT in 62 (96.8%). The cystic artery was shown to originate in the proper, right, middle, and left hepatic artery in one, 58, two, and one patient, respectively. These results show that CBCT was more useful than DSA for identifying cystic arterial origin. Therefore CBCT should be positively applied during TAE. (author)

  17. Conventional digital subtraction x-ray angiography versus magnetic resonance angiography in the evaluation of carotid disease: patient satisfaction and preferences

    Energy Technology Data Exchange (ETDEWEB)

    U-King-Im, J.M. E-mail: jhg21@cam.ac.uk; Trivedi, R.; Cross, J.; Higgins, N.; Graves, M.; Kirkpatrick, P.; Antoun, N.; Gillard, J.H

    2004-04-01

    AIM: To compare conventional digital subtraction x-ray angiography (DSA) and contrast-enhanced magnetic resonance angiography (MRA) of the carotid arteries in terms of patient satisfaction and preferences. METHODS: One hundred and sixty-seven patients with symptomatic carotid artery disease, who underwent both DSA and MRA, were prospectively recruited in this study. Patients' perceptions of each method were assessed by the use of a questionnaire after each procedure. Main outcome measures were anxiety, pain, satisfaction rate and patient preferences. RESULTS: DSA generated more anxiety and pain during the procedure, but the severity of these ill-effects was mild. Satisfaction rates for each method were similar. More patients were, however, willing to have a repeat MRA compared with DSA (67 versus 41%). The majority of patients (62%) preferred MRA over DSA (31%). The shorter MRA imaging time was found to be a significant factor in patients' acceptance of the technique. The main reasons cited by patients for their dislike of a particular procedure was noise and claustrophobia for MRA and invasiveness, pain and post-procedural bed rest for DSA. CONCLUSIONS: MRA is the method that is preferred by the majority of patients, although the actual disutility of DSA may be small. Assuming equal diagnostic accuracy, our data supports replacement of DSA by MRA for routine carotid imaging.

  18. Decision making in the treatment of peripheral arterial disease - A single-institution comparative study using information from color doppler and digital subtraction angiogram studies

    International Nuclear Information System (INIS)

    Koshy, Chiramel G; Chacko, Binita R; Keshava, Shyamkumar N; Stephen, Edwin; Agarwal, Sunil

    2011-01-01

    Numerous studies have compared the accuracy of color Doppler (CD) with that of digital subtraction angiography (DSA) in the diagnosis of peripheral arterial disease (PAD). However, only a few have looked at the influence of these diagnostic tests on the treatment decision in PAD. This study evaluated the differences in treatment decisions that were based on CD and with those based on DSA findings. Findings from CD and DSA studies obtained in 40 patients were entered on line diagrams by two radiologists working separately. These were randomized and sent to three experienced clinicians – two vascular surgeons and one interventional radiologist. The treatment decisions of the clinicians based on each proforma were collected and analyzed to look for the degree of agreement between Doppler-based and DSA-based decisions. There was fair to moderate agreement between CD-based and DSA-based decisions for all three clinicians, with some improvement in agreement with the addition of clinical data. The vascular surgeons showed better agreement with each other on treatment decisions compared to the interventional radiologist who showed a fair-to-moderate level of agreement with the vascular surgeons, which did not significantly change with the addition of clinical data. There is a fair to moderate agreement between treatment decisions based on CD findings and those based on DSA findings. We conclude that CD along with clinical data is sufficient to make decisions in the treatment of PAD

  19. Conventional digital subtraction x-ray angiography versus magnetic resonance angiography in the evaluation of carotid disease: patient satisfaction and preferences

    International Nuclear Information System (INIS)

    U-King-Im, J.M.; Trivedi, R.; Cross, J.; Higgins, N.; Graves, M.; Kirkpatrick, P.; Antoun, N.; Gillard, J.H.

    2004-01-01

    AIM: To compare conventional digital subtraction x-ray angiography (DSA) and contrast-enhanced magnetic resonance angiography (MRA) of the carotid arteries in terms of patient satisfaction and preferences. METHODS: One hundred and sixty-seven patients with symptomatic carotid artery disease, who underwent both DSA and MRA, were prospectively recruited in this study. Patients' perceptions of each method were assessed by the use of a questionnaire after each procedure. Main outcome measures were anxiety, pain, satisfaction rate and patient preferences. RESULTS: DSA generated more anxiety and pain during the procedure, but the severity of these ill-effects was mild. Satisfaction rates for each method were similar. More patients were, however, willing to have a repeat MRA compared with DSA (67 versus 41%). The majority of patients (62%) preferred MRA over DSA (31%). The shorter MRA imaging time was found to be a significant factor in patients' acceptance of the technique. The main reasons cited by patients for their dislike of a particular procedure was noise and claustrophobia for MRA and invasiveness, pain and post-procedural bed rest for DSA. CONCLUSIONS: MRA is the method that is preferred by the majority of patients, although the actual disutility of DSA may be small. Assuming equal diagnostic accuracy, our data supports replacement of DSA by MRA for routine carotid imaging

  20. Postoperative three-dimensional CT angiography after cerebral aneurysm clipping with titanium clips: detection with single detector CT. Comparison with intra-arterial digital subtraction angiography

    International Nuclear Information System (INIS)

    Sakuma, I.; Tomura, N.; Kinouchi, H.; Takahashi, S.; Otani, T.; Watarai, J.; Mizoi, K.

    2006-01-01

    AIM: To assess the significance of three-dimensional computed tomography angiography (3D-CTA) in detecting remnant necks after cerebral aneurysm clipping. MATERIALS AND METHODS: A total of 59 patients (77 aneurysms) underwent surgery using titanium clips. Two blinded observers independently evaluated the presence of neck remnants on shaded-surface display (SSD) imaging, volume rendered (VR) imaging, and intra-arterial digital subtraction angiography (IADSA). RESULTS: Mean sensitivity and specificity for detecting neck remnants were 50.0 and 74.2% for SSD imaging, 61.5 and 82.8% for VR imaging, and 92.3 and 92.2% for IADSA, respectively. Receiver operating characteristic (ROC) analysis revealed excellent diagnostic performance for IADSA [mean area under ROC curve (Az)=0.97], and good diagnostic performance for 3D-CTA (Az=0.70 and 0.76 for SSD and VR, respectively). Specificity of VR was better than that SSD (p=0.082), however, there was no significant difference between them. CONCLUSION: Use of 3D-CTA techniques can facilitate postoperative evaluation

  1. Intra-arterial digital subtraction angiography of the pulmonary arteries using a flow-directed balloon catheter in the diagnosis of pulmonary embolism

    International Nuclear Information System (INIS)

    Rooij, W.J.J. van; Heeten, G.J. den

    1992-01-01

    Selective intra-arterial digital subtraction angiography (IA-DSA) of the pulmonary vessels was performed in 70 patients suspected of acute pulmonary embolism. A flow-directed Swan-Ganz pulmonary angiography catheter was used. The spatial resolution of the equipment used was 3.3 lp/mm for DSA and 6.0 lp/mm for conventional pulmonary angiography (CPA). Image quality of the angiograms was assessed by determining the highest visible branching division of the main pulmonary artery. The mean visible branching division for IA-DSA was 4.71 (range 3-7). In 10 patients where IA-DSA and CPA were performed during the same procedure there was no difference in visualization of peripheral arteries (mean 4.70 visible or for both modalities). IA-DSA makes the procedure rapid, saves on films and contrast material and allows good visualization of areas where exposure is difficult. The spatial resolution of state-of-the-art equipment permits sufficient definition of subsegmental vessels. The use of the flow-directed balloon catheter makes the examination easy to perform and minimizes the risk of catheter induced cardiac arrhythmias. (orig.) [de

  2. Four-dimensional CT angiography (4D-CTA) in the evaluation of juvenile nasopharyngeal angiofibromas: comparison with digital subtraction angiography (DSA) and surgical findings.

    Science.gov (United States)

    Xiao, Zebin; Zheng, Yingyan; Li, Jian; Chen, Dehua; Liu, Fang; Cao, Dairong

    2017-12-01

    To explore the value of four-dimensional CT angiography (4D-CTA) in the preoperative evaluation of juvenile nasopharyngeal angiofibromas (JNAs) using 320-row volume CT. 4D-CTA and DSA data of 18 patients with histopathologically proven JNAs were retrospectively reviewed. The location, extent, feeding vessels and stage of JNAs were assessed by two radiologists independently and blindly. The agreements between both reviewers and between 4D-CTA and surgical findings for assessing the above indicators were analysed, respectively. The radiation dose and the number of feeding arteries between 4D-CTA and digital subtraction angiography (DSA) were also compared. 4D-CTA showed high diagnostic consistency with surgical pathology for JNAs with consistent rates of 96.2 and 100% in both reviewers, respectively. The effective dose of 4D-CTA was significantly less than that of DSA (p 0.05). 4D-CTA can provide a reliable preoperative diagnosis and assessment of JNAs, which is useful for determining the surgical strategy and management of this condition.

  3. Dual-energy CT head bone and hard plaque removal for quantification of calcified carotid stenosis: utility and comparison with digital subtraction angiography

    International Nuclear Information System (INIS)

    Uotani, Kensuke; Watanabe, Yoshiyuki; Higashi, Masahiro; Nakazawa, Tetsuro; Kono, Atsushi K.; Hori, Yoshiro; Fukuda, Tetsuya; Kanzaki, Suzu; Yamada, Naoaki; Naito, Hiroaki; Itoh, Toshihide; Sugimura, Kazuro

    2009-01-01

    We evaluated quantification of calcified carotid stenosis by dual-energy (DE) CTA and dual-energy head bone and hard plaque removal (DE hard plaque removal) and compared the results to those of digital subtraction angiography (DSA). Eighteen vessels (13 patients) with densely calcified carotid stenosis were examined by dual-source CT in the dual-energy mode (tube voltages 140 kV and 80 kV). Head bone and hard plaques were removed from the dual-energy images by using commercial software. Carotid stenosis was quantified according to NASCET criteria on MIP images and DSA images at the same plane. Correlation between DE CTA and DSA was determined by cross tabulation. Accuracies for stenosis detection and grading were calculated. Stenosis could be evaluated in all vessels by DE CTA after applying DE hard plaque removal. In contrast, conventional CTA failed to show stenosis in 13 out of 18 vessels due to overlapping hard plaque. Good correlation between DE plaque removal images and DSA images was observed (r 2 =0.9504) for stenosis grading. Sensitivity and specificity to detect hemodynamically relevant (>70%) stenosis was 100% and 92%, respectively. Dual-energy head bone and hard plaque removal is a promising tool for the evaluation of densely calcified carotid stenosis. (orig.)

  4. Evaluation of the vascular anatomy in potential living kidney donors with gadolinium-enhanced magnetic resonance angiography: comparison with digital subtraction angiography and intraoperative findings.

    Science.gov (United States)

    Asgari, Majid A; Dadkhah, Farid; Ghadian, Ali R; Razzaghi, Mohammad R; Noorbala, Mohammad H; Amini, Erfan

    2011-01-01

    X-ray contrast arteriography has traditionally been used for pre-operative evaluation in living kidney donors. However, magnetic resonance angiography (MRA) offers a non-invasive alternative, which has been considered to be less accurate. This study was performed to determine whether MRA in the pre-operative investigation of living kidney donors provides sufficient information. From December 2005 to December 2007, 173 potential live donors were evaluated in this study. Donors performed digital subtraction angiography (DSA) and those with one or more accessory arteries at least on one side recruited for further evaluation with three-dimensional gadolinium-enhanced MRA. A total of 30 donors constituted the study population. When compared with DSA as the reference method, MRA detected 20 of 36 renal accessory arteries which indicates a sensitivity of 55.6%. The difference between MRA and DSA in identifying accessory renal arteries was significant (p-value kidneys. MRA has the advantage of avoiding exposure to ionizing radiation and is non-invasive. These are important considerations in pre-operative evaluation of a generally healthy donor population. However, MRA provides suboptimal accuracy in detecting small accessory arteries. © 2010 John Wiley & Sons A/S.

  5. Comparison of high-resolution contrast-enhanced 3D MRA with digital subtraction angiography in the evaluation of hepatic arterial anatomy

    International Nuclear Information System (INIS)

    Matoba, M.; Tonami, H.; Kuginuki, M.; Yokota, H.; Takashima, S.; Yamamoto, I.

    2003-01-01

    AIM: To evaluate the validity of high-resolution contrast-enhanced three-dimensional magnetic resonance angiography (MRA) in defining hepatic arterial anatomy and to compare this with digital subtraction angiography (DSA). MATERIALS AND METHODS: MRA and DSA were performed in 30 patients. MRA was performed with breath-hold, gadolinium-enhanced, three-dimensional, fast low-angle shot sequence with a 512 pixel matrix. MRA was compared with DSA in terms of image quality and depiction of hepatic arterial anatomy. The agreement in image quality between MRA and DSA was determined with the kappa statistic. RESULTS: With respect to image quality, there was excellent or good correlation between MRA and DSA for the common hepatic artery (κ=0.85), proper hepatic artery (κ=0.72), gastroduodenal artery (κ=0.70), left hepatic artery (κ=0.49), left gastric artery (κ=0.50), splenic artery (κ=0.84), and superior mesenteric artery (κ=0.88). Poor correlation was found for the right hepatic artery (κ=0.18) and right gastric artery (κ=0.38). With regard to hepatic arterial anatomy, MRA correlated correctly with DSA in 28 of the 29 cases, i.e. 97% of patients. CONCLUSION: MRA is a useful technique for the evaluation of the hepatic artery, and for the vast majority of patients, MRA can replace intra-arterial DSA

  6. The dural entrance of cerebral bridging veins into the superior sagittal sinus: an anatomical comparison between cadavers and digital subtraction angiography

    International Nuclear Information System (INIS)

    Han, Hui; Tao, Wei; Zhang, Ming

    2007-01-01

    Intracranial venous structures have received increasing attention due to improved neuroimaging techniques and increased awareness of cerebral venous disease. To date, few studies have attempted to investigate the dural entrance of the cerebral bridging vein (BV). The aim of this study was to use the superior sagittal sinus (SSS) as an example to identify anatomical features of the dural entrance of the BVs into the SSS in both human cadavers and digital subtraction angiography (DSA) images. A total of 30 adult and 7 fetal human cadavers and 36 patients were examined with anatomical dissections, vascular casting and DSA. The number, diameter and angle of the BVs entering the SSS were measured and compared between the cadavers and DSA images. The results demonstrated that (1) the way a BV entered the SSS varied in three dimensions, and thus the BV dural entrance was difficult to precisely localize by DSA, (2) the distribution pattern of the dural entrance of the BVs into the SSS was relatively constant and a nontributary segment of the SSS was centered at the coronal suture and was identifiable by DSA, and (3) nearly all the BVs (97%, 561/581) entered the SSS at an angle opposite to the direction of blood flow. Unique anatomical features of the dural entrance of a BV into the SSS should be considered in neuroimaging interpretation of the sinus and its associated veins. (orig.)

  7. Comparison of remnant size in embolized intracranial aneurysms measured at follow-up with DSA and MRA

    Energy Technology Data Exchange (ETDEWEB)

    Serafin, Zbigniew; Strzesniewski, Piotr; Lasek, Wladyslaw [Nicolaus Copernicus University, Department of Radiology and Diagnostic Imaging, Collegium Medicum, Bydgoszcz (Poland); Beuth, Wojciech [University of Humanities and Economics in Wloclawek, Faculty of Health Sciences, Wloclawek (Poland)

    2012-12-15

    The possibility of recanalization and the need for retreatment are the most important limitations of intracranial aneurysm embolization. The purpose of the study was to compare the size of aneurysm remnants measured at follow-up with three-dimensional digital subtracted angiography (3D-DSA) and magnetic resonance angiography (MRA). Twenty-six aneurysms were found incompletely occluded in 72 consecutively examined patients at a follow-up after 3 months. The diameters and volume of aneurysm remnants were compared between 3D-DSA, time-of-flight MRA (TOF-MRA), contrast-enhanced TOF-MRA (CE-TOF-MRA), and contrast-enhanced MRA (CE-MRA) at 1.5 T. There was a significant correlation between remnant volumes calculated based on 3D-DSA and all MRA modalities. The intraobserver variability of the measurements ranged from 3.4 to 4.1 % and the interobserver variability from 5.8 to 7.3 %. There were no significant differences in the variability between the techniques. The mean residual filling volume ranged from 16.3 {+-} 19.0 mm{sup 3} in TOF-MRA to 30.5 {+-} 44.6 mm{sup 3} in 3D-DSA (P < 0.04). Significant differences were found in the volumes measured with 3D-DSA and CE-MRA as compared to TOF-MRA and CE-TOF-MRA (P < 0.01). There was a moderate significant correlation between the residual filling and the relative error of measurement in the case of TOF-MRA and CE-TOF-MRA. TOF-MRA seems to underestimate the size of aneurysm remnants detected at follow-up and should not be used as a sole imaging method to decide on re-embolization. (orig.)

  8. Comparison of remnant size in embolized intracranial aneurysms measured at follow-up with DSA and MRA

    International Nuclear Information System (INIS)

    Serafin, Zbigniew; Strzesniewski, Piotr; Lasek, Wladyslaw; Beuth, Wojciech

    2012-01-01

    The possibility of recanalization and the need for retreatment are the most important limitations of intracranial aneurysm embolization. The purpose of the study was to compare the size of aneurysm remnants measured at follow-up with three-dimensional digital subtracted angiography (3D-DSA) and magnetic resonance angiography (MRA). Twenty-six aneurysms were found incompletely occluded in 72 consecutively examined patients at a follow-up after 3 months. The diameters and volume of aneurysm remnants were compared between 3D-DSA, time-of-flight MRA (TOF-MRA), contrast-enhanced TOF-MRA (CE-TOF-MRA), and contrast-enhanced MRA (CE-MRA) at 1.5 T. There was a significant correlation between remnant volumes calculated based on 3D-DSA and all MRA modalities. The intraobserver variability of the measurements ranged from 3.4 to 4.1 % and the interobserver variability from 5.8 to 7.3 %. There were no significant differences in the variability between the techniques. The mean residual filling volume ranged from 16.3 ± 19.0 mm 3 in TOF-MRA to 30.5 ± 44.6 mm 3 in 3D-DSA (P < 0.04). Significant differences were found in the volumes measured with 3D-DSA and CE-MRA as compared to TOF-MRA and CE-TOF-MRA (P < 0.01). There was a moderate significant correlation between the residual filling and the relative error of measurement in the case of TOF-MRA and CE-TOF-MRA. TOF-MRA seems to underestimate the size of aneurysm remnants detected at follow-up and should not be used as a sole imaging method to decide on re-embolization. (orig.)

  9. Comparison of remnant size in embolized intracranial aneurysms measured at follow-up with DSA and MRA.

    Science.gov (United States)

    Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

    2012-12-01

    The possibility of recanalization and the need for retreatment are the most important limitations of intracranial aneurysm embolization. The purpose of the study was to compare the size of aneurysm remnants measured at follow-up with three-dimensional digital subtracted angiography (3D-DSA) and magnetic resonance angiography (MRA). Twenty-six aneurysms were found incompletely occluded in 72 consecutively examined patients at a follow-up after 3 months. The diameters and volume of aneurysm remnants were compared between 3D-DSA, time-of-flight MRA (TOF-MRA), contrast-enhanced TOF-MRA (CE-TOF-MRA), and contrast-enhanced MRA (CE-MRA) at 1.5 T. There was a significant correlation between remnant volumes calculated based on 3D-DSA and all MRA modalities. The intraobserver variability of the measurements ranged from 3.4 to 4.1 % and the interobserver variability from 5.8 to 7.3 %. There were no significant differences in the variability between the techniques. The mean residual filling volume ranged from 16.3 ± 19.0 mm(3) in TOF-MRA to 30.5 ± 44.6 mm(3) in 3D-DSA (P < 0.04). Significant differences were found in the volumes measured with 3D-DSA and CE-MRA as compared to TOF-MRA and CE-TOF-MRA (P < 0.01). There was a moderate significant correlation between the residual filling and the relative error of measurement in the case of TOF-MRA and CE-TOF-MRA. TOF-MRA seems to underestimate the size of aneurysm remnants detected at follow-up and should not be used as a sole imaging method to decide on re-embolization.

  10. Quantitative Real-Time Fluoroscopy Analysis on Measurement of the Hepatic Arterial Flow During Transcatheter Arterial Chemoembolization of Hepatocellular Carcinoma: Comparison with Quantitative Digital Subtraction Angiography Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Yang; Lee, Rheun-Chuan, E-mail: rclee@vghtpe.gov.tw; Guo, Wan-Yuo, E-mail: wyguo@vghtpe.gov.tw; Chu, Wei-Fa [Taipei Veterans General Hospital, Department of Radiology (China); Wu, Frank Chun-Hsien [Siemens Healthcare Ltd. (China); Gehrisch, Sonja [Siemens Healthcare GmbH (Germany)

    2016-11-15

    PurposeTo quantify the arterial flow change during transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) using digital subtraction angiography, quantitative color-coding analysis (d-QCA), and real-time subtraction fluoroscopy QCA (f-QCA).Materials and MethodsThis prospective study enrolled 20 consecutive patients with HCC who had undergone TACE via a subsegmental approach between February 2014 and April 2015. The TACE endpoint was a sluggish antegrade tumor-feeding arterial flow. d-QCA and f-QCA were used for determining the relative maximal density time (rT{sub max}) of the selected arteries. The rT{sub max} of the selected arteries was analyzed in d-QCA and f-QCA before and after TACE, and its correlation in both analyses was evaluated.ResultsThe pre- and post-TACE rT{sub max} of the embolized segmental artery in d-QCA and f-QCA were 1.59 ± 0.81 and 2.97 ± 1.80 s (P < 0.001) and 1.44 ± 0.52 and 2.28 ± 1.02 s (P < 0.01), respectively. The rT{sub max} of the proximal hepatic artery did not significantly change during TACE in d-QCA and f-QCA. The Spearman correlation coefficients of the pre- and post-TACE rT{sub max} of the embolized segmental artery between d-QCA and f-QCA were 0.46 (P < 0.05) and 0.80 (P < 0.001). Radiation doses in one series of d-QCA and f-QCA were 140.7 ± 51.5 milligray (mGy) and 2.5 ± 0.7 mGy, respectively.Conclusionsf-QCA can quantify arterial flow changes with a higher temporal resolution and lower radiation dose. Flow quantification of the embolized segmental artery using f-QCA and d-QCA is highly correlated.

  11. TU-CD-207-03: Time Evolution of Texture Parameters of Subtracted Images Obtained by Contrast-Enhanced Digital Mammography (CEDM)

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, M-J; Brandan, M-E [Instituto de Fisica, Universidad Nacional Autonom de Mexico, Mexico, Distrito Federal (Mexico); Gastelum, A; Marquez, J [Centro de Ciencias Aplicadas y Desarrollo Tecnologico Universidad Nacional Autonoma de Mexico, Mexico, Distrito Federal (Mexico)

    2015-06-15

    Purpose: To evaluate the time evolution of texture parameters, based on the gray level co-occurrence matrix (GLCM), in subtracted images of 17 patients (10 malignant and 7 benign) subjected to contrast-enhanced digital mammography (CEDM). The goal is to determine the sensitivity of texture to iodine uptake at the lesion, and its correlation (or lack of) with mean-pixel-value (MPV). Methods: Acquisition of clinical images followed a single-energy CEDM protocol using Rh/Rh/48 kV plus external 0.5 cm Al from a Senographe DS unit. Prior to the iodine-based contrast medium (CM) administration a mask image was acquired; four CM images were obtained 1, 2, 3, and 5 minutes after CM injection. Temporal series were obtained by logarithmic subtraction of registered CM minus mask images.Regions of interest (ROI) for the lesion were drawn by a radiologist and the texture was analyzed. GLCM was evaluated at a 3 pixel distance, 0° angle, and 64 gray-levels. Pixels identified as registration errors were excluded from the computation. 17 texture parameters were chosen, classified according to similarity into 7 groups, and analyzed. Results: In all cases the texture parameters within a group have similar dynamic behavior. Two texture groups (associated to cluster and sum mean) show a strong correlation with MPV; their average correlation coefficient (ACC) is r{sup 2}=0.90. Other two groups (contrast, homogeneity) remain constant with time, that is, a low-sensitivity to CM uptake. Three groups (regularity, lacunarity and diagonal moment) are sensitive to CM uptake but less correlated with MPV; their ACC is r{sup 2}=0.78. Conclusion: This analysis has shown that, at least groups associated to regularity, lacunarity and diagonal moment offer dynamical information additional to the mean pixel value due to the presence of CM at the lesion. The next step will be the analysis in terms of the lesion pathology. Authors thank PAPIIT-IN105813 for support. Consejo Nacional de Ciencia Y

  12. Quantitative Real-Time Fluoroscopy Analysis on Measurement of the Hepatic Arterial Flow During Transcatheter Arterial Chemoembolization of Hepatocellular Carcinoma: Comparison with Quantitative Digital Subtraction Angiography Analysis

    International Nuclear Information System (INIS)

    Lin, Yi-Yang; Lee, Rheun-Chuan; Guo, Wan-Yuo; Chu, Wei-Fa; Wu, Frank Chun-Hsien; Gehrisch, Sonja

    2016-01-01

    PurposeTo quantify the arterial flow change during transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) using digital subtraction angiography, quantitative color-coding analysis (d-QCA), and real-time subtraction fluoroscopy QCA (f-QCA).Materials and MethodsThis prospective study enrolled 20 consecutive patients with HCC who had undergone TACE via a subsegmental approach between February 2014 and April 2015. The TACE endpoint was a sluggish antegrade tumor-feeding arterial flow. d-QCA and f-QCA were used for determining the relative maximal density time (rT_m_a_x) of the selected arteries. The rT_m_a_x of the selected arteries was analyzed in d-QCA and f-QCA before and after TACE, and its correlation in both analyses was evaluated.ResultsThe pre- and post-TACE rT_m_a_x of the embolized segmental artery in d-QCA and f-QCA were 1.59 ± 0.81 and 2.97 ± 1.80 s (P < 0.001) and 1.44 ± 0.52 and 2.28 ± 1.02 s (P < 0.01), respectively. The rT_m_a_x of the proximal hepatic artery did not significantly change during TACE in d-QCA and f-QCA. The Spearman correlation coefficients of the pre- and post-TACE rT_m_a_x of the embolized segmental artery between d-QCA and f-QCA were 0.46 (P < 0.05) and 0.80 (P < 0.001). Radiation doses in one series of d-QCA and f-QCA were 140.7 ± 51.5 milligray (mGy) and 2.5 ± 0.7 mGy, respectively.Conclusionsf-QCA can quantify arterial flow changes with a higher temporal resolution and lower radiation dose. Flow quantification of the embolized segmental artery using f-QCA and d-QCA is highly correlated.

  13. Self-masking subtraction tomosynthesis

    International Nuclear Information System (INIS)

    Chakraborty, D.P.; Yester, M.V.; Barnes, G.T.; Lakshminarayanan, A.V.

    1984-01-01

    The authors tested the image quality and dose savings of self-masking subtraction tomosynthesis (SST), which combines digital tomosynthesis with subtraction of a blurred self-mask. High-quality images of the inner ear of a head phantom were obtained at moderate dose savings. Although they were taken with linear motion, they did not exhibit the streaking due to off-fulcrum objects that is characteristic of conventional linear tomography. SST could reduce patient dose by a factor of at least 12 in examinations of the inner ear, and the mechanical aspects can be implemented with moderate modifications of existing instrumentation

  14. Noninvasive follow-up of GDC-treated saccular aneurysms by MR angiography

    International Nuclear Information System (INIS)

    Weber, W.; Henkes, H.; Nahser, H.C.; Roer, N.; Kuehne, D.; Yousry, T.A.; Felber, S.R.

    2001-01-01

    The aim of this study was to determine sensitivity and specificity of magnetic resonance angiography (MRA) for the assessment of durable occlusion of intracranial aneurysms with Guglielmi detachable coils (GDC) and to point out the influence of MRA results in re-intervention strategies. Forty-five patients with 54 aneurysms that were previously treated by endovascular occlusion with GDC were selected for this study. All patients underwent digital subtraction angiography (DSA) and MRA examinations on the same day. The time-of-flight MRA studies were performed on a 1-T scanner. The MRA images were first read by radiologists who were not aware of the DSA results. In a second consensus reading by the neuroradiologists who had performed all interventional procedures of this series, the decision was made as to whether re-treatment was necessary. The distribution of aneurysm sizes, configurations and treatment results were sufficient for an unbiased evaluation. The first blinded evaluation revealed a sensitivity of 71% and a specificity of 95% for MRA assessment of aneurysm reperfusion. In the second consensus reading, the sensitivity increased to 92% and the specificity was 98%. The blinded reading indicates that MRA is a useful adjunct to DSA for the assessment of durable results after endovascular treatment of intracranial aneurysms. In the consensus reading it became obvious that sensitivity and specificity of MRA can be increased to 92 and 98%, respectively, if the results were evaluated by experienced neuroradiologists, including prior knowledge of all other examinations. We have already increased the follow-up intervals for DSA and use MRA intermittently, based on these results. (orig.)

  15. Assessment of the left ventricular systolic and diastolic function by the left ventricular density curve derived from intravenous digital subtraction angiography in children

    International Nuclear Information System (INIS)

    Horigome, Hitoshi; Satoh, Hideo; Isobe, Takeshi; Takita, Hitoshi

    1991-01-01

    To evaluate the left ventricular (LV) systolic and diastolic function, fifty-four children with various heart diseases underwent intravenous digital subtraction angiography (IV-DSA). Global left ventricular density curve was obtained through densitometry of the DSA images. The curve was smoothed by a third-degree Fourier transformation and systolic and diastolic indexes were obtained. In the control group, consisting of Kawasaki disease without coronary lesion and mild pulmonary stenosis, the peak ejection rate (PER) and the peak filling rate in early diastole (PFR-E) correlated positively with the heart rate (HR) in a quadratic curve manner [PER: r= 0.93 p<0.01, PFR-E: r= 0.94 p<0.01]. Time from end-diastolic to PER (T-PER) and time from end-systolic to PFR (T-PFR) were correlated negatively with HR [T-PER: r=-0.86 p<0.01, T-PFR: r=-0.91 p<0.01]. However, T-PER/RR and T-PFR/RR values were rather constant (20.9±3.2%, 17.0±2.6%, respectively). We also found significant correlations of PER and PFR-E with left ventricular ejection fraction (LVEF). Patients with corrected tetralogy of Fallot and with cardiomyopaties showed not only abnormal systolic indexes but some depressed diastolic indexes. LV density curve also disclosed isolated diastolic dysfunction in a group of aortic stenosis and in two patients with coronary lesions. A correlation of LVEF derived from the density curve and conventional area-length method was high [r= 0.91 p<0.001]. To evaluate the reproducibility, we were able to obtain the digital data twice with over one month interval on 24 patients. The intraobserver correlation was satisfactory. We applied the remasking method, resulting in improving the quality of digital images under spontaneous breathing. Our results indicated that IV-DSA was a less-invasive and clinically reliable method for assessment of LV function in children. (author)

  16. Assessment of the left ventricular systolic and diastolic function by the left ventricular density curve derived from intravenous digital subtraction angiography in children

    Energy Technology Data Exchange (ETDEWEB)

    Horigome, Hitoshi; Satoh, Hideo; Isobe, Takeshi; Takita, Hitoshi (Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine)

    1991-05-01

    To evaluate the left ventricular (LV) systolic and diastolic function, fifty-four children with various heart diseases underwent intravenous digital subtraction angiography (IV-DSA). Global left ventricular density curve was obtained through densitometry of the DSA images. The curve was smoothed by a third-degree Fourier transformation and systolic and diastolic indexes were obtained. In the control group, consisting of Kawasaki disease without coronary lesion and mild pulmonary stenosis, the peak ejection rate (PER) and the peak filling rate in early diastole (PFR-E) correlated positively with the heart rate (HR) in a quadratic curve manner (PER: r= 0.93 p<0.01, PFR-E: r= 0.94 p<0.01). Time from end-diastolic to PER (T-PER) and time from end-systolic to PFR (T-PFR) were correlated negatively with HR (T-PER: r=-0.86 p<0.01, T-PFR: r=-0.91 p<0.01). However, T-PER/RR and T-PFR/RR values were rather constant (20.9+-3.2%, 17.0+-2.6%, respectively). We also found significant correlations of PER and PFR-E with left ventricular ejection fraction (LVEF). Patients with corrected tetralogy of Fallot and with cardiomyopaties showed not only abnormal systolic indexes but some depressed diastolic indexes. LV density curve also disclosed isolated diastolic dysfunction in a group of aortic stenosis and in two patients with coronary lesions. A correlation of LVEF derived from the density curve and conventional area-length method was high (r= 0.91 p<0.001). To evaluate the reproducibility, we were able to obtain the digital data twice with over one month interval on 24 patients. The intraobserver correlation was satisfactory. We applied the remasking method, resulting in improving the quality of digital images under spontaneous breathing. Our results indicated that IV-DSA was a less-invasive and clinically reliable method for assessment of LV function in children. (author).

  17. Catheter radiofrequency ablation for arrhythmias under the guidance of the Carto 3 three-dimensional mapping system in an operating room without digital subtraction angiography.

    Science.gov (United States)

    Huang, Xingfu; Chen, Yanjia; Huang, Zheng; He, Liwei; Liu, Shenrong; Deng, Xiaojiang; Wang, Yongsheng; Li, Rucheng; Xu, Dingli; Peng, Jian

    2018-06-01

    Several studies have reported the efficacy of a zero-fluoroscopy approach for catheter radiofrequency ablation of arrhythmias in a digital subtraction angiography (DSA) room. However, no reports are available on the ablation of arrhythmias in the absence of DSA in the operating room. To investigate the efficacy and safety of catheter radiofrequency ablation for arrhythmias under the guidance of a Carto 3 three-dimensional (3D) mapping system in an operating room without DSA. Patients were enrolled according to the type of arrhythmia. The Carto 3 mapping system was used to reconstruct heart models and guide the electrophysiologic examination, mapping, and ablation. The total procedure, reconstruction, electrophysiologic examination, and mapping times were recorded. Furthermore, immediate success rates and complications were also recorded. A total of 20 patients were enrolled, including 12 males. The average age was 51.3 ± 17.2 (19-76) years. Nine cases of atrioventricular nodal re-entrant tachycardia, 7 cases of frequent ventricular premature contractions, 3 cases of Wolff-Parkinson-White syndrome, and 1 case of typical atrial flutter were included. All arrhythmias were successfully ablated. The procedure time was 127.0 ± 21.0 (99-177) minutes, the reconstruction time was 6.5 ± 2.9 (3-14) minutes, the electrophysiologic study time was 10.4 ± 3.4 (6-20) minutes, and the mapping time was 11.7 ± 8.3 (3-36) minutes. No complications occurred. Radiofrequency ablation of arrhythmias without DSA is effective and feasible under the guidance of the Carto 3 mapping system. However, the electrophysiology physician must have sufficient experience, and related emergency measures must be present to ensure safety.

  18. Quantitative perfusion computed tomography measurements of cerebral hemodynamics: Correlation with digital subtraction angiography identified primary and secondary cerebral collaterals in internal carotid artery occlusive disease

    International Nuclear Information System (INIS)

    Cheng Xiaoqing; Tian Jianming; Zuo Changjing; Liu Jia; Zhang Qi; Lu Guangming

    2012-01-01

    Background: The aim of the present study was to assess hemodynamic variations in symptomatic unilateral internal carotid artery occlusion (ICAO) patients with primary collateral flow via circle of Willis or secondary collateral flow via ophthalmic artery and/or leptomeningeal collaterals. Methods: Thirty-eight patients with a symptomatic unilateral ICAO were enrolled in the study. Based on digital subtraction angiography (DSA) findings, patients were classified into 2 groups: primary collateral (n = 14) and secondary collateral (n = 24) groups. Collateral flow hemodynamics were investigated with perfusion computed tomography (PCT) by measuring the cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP) in the hemispheres ipsilateral and contralateral to ICAO. Based on the measurements, the ipsilateral to contralateral ratio for each parameter was calculated and compared. Results: Irrespective of the collateral patterns, ipsilateral CBF was not significantly different from that of the contralateral hemisphere (P = 0.285); ipsilateral CBV and TTP was significantly increased compared with those of the contralateral hemisphere (P = 0.000 and P = 0.000 for CBV and TTP, respectively). Furthermore, patients with secondary collaterals had significantly larger ipsilateral-to-contralateral ratios for both CBV (rCBV, P = 0.0197) and TTP (rTTP, P = 0.000) than those of patients with only primary collaterals. These two groups showed no difference in ipsilateral-to-contralateral ratio for CBF (rCBF, P = 0.312). Conclusion: Patients with symptomatic unilateral ICAO in our study were in an autoregulatory vasodilatation status. Moreover, secondary collaterals in ICAO patients were correlated with ipsilateral CBV and delayed TTP that suggested severe hemodynamic impairment, presumably increasing the risk of ischemic events.

  19. Value of Single-Dose Contrast-Enhanced Magnetic Resonance Angiography Versus Intraarterial Digital Subtraction Angiography in Therapy Indications in Abdominal and Iliac Arteries

    International Nuclear Information System (INIS)

    Schaefer, Philipp J.; Schaefer, Fritz K. W.; Mueller-Huelsbeck, Stefan; Both, Markus; Heller, Martin; Jahnke, Thomas

    2007-01-01

    The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committee was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30 o , field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses ≥50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies

  20. Comparison of gadofosveset-enhanced three-dimensional magnetic resonance angiography with digital subtraction angiography for lower-extremity peripheral arterial occlusive disease

    International Nuclear Information System (INIS)

    Grijalba, Fermin Urtasun; Esandi, Mercedes Ciriza

    2010-01-01

    Background: Minimally invasive imaging techniques are increasingly used for clinical decision making in patients with peripheral arterial occlusive disease (PAOD). Purpose: To assess whether gadofosveset-enhanced three-dimensional (3D) magnetic resonance (MR) angiography could replace digital subtraction angiography (DSA) for the evaluation of lower-extremity PAOD. Material and Methods: Thirty patients with symptomatic PAOD underwent prospectively both MR angiography and DSA. Gadofosveset-enhanced 3D MR angiography was performed on a 1.5T system equipped with a peripheral angio matrix coil. Four blinded observers independently analyzed MR angiograms and DSA images. The lower arterial vascular system was divided into three anatomic segments (aortoiliac, femoropopliteal, infrapopliteal) for review. The status of each segment was graded as normal, stenosis less than 50%, stenosis greater than 50%, or occluded and/or aneurismatic. Principal and secondary lesions were reported. Results: Although interobserver agreement for both was excellent, it was higher for DSA (?=0.92) than for MR angiography (?=0.86) for reporting the principal and secondary lesions in all segments. For different anatomic locations, the interobserver agreement of MR angiography and DSA was as follows: aortoiliac (?=0.93, k=0.95), femoropopliteal (?=0.86, k=0.90), and infrapopliteal (?=0.78, k=0.85). The lowest agreement was found for MR angiography on infrapopliteal segments (?=0.78). In four (13.3%) cases, MR angiography showed lesions that were not found by DSA. Five (16.6%) aneurysm cases, not observed by DSA, were shown by MR angiography. Conclusion: Gadofosveset-enhanced 3D MR angiography can be proposed for first-line imaging in the management of lower-limb PAOD patients and permits the selective use of DSA as a second-line examination when MR angiography fails or in an endovascular approach

  1. A novel approach to background subtraction in contrast-enhanced dual-energy digital mammography with commercially available mammography devices: Noise minimization

    International Nuclear Information System (INIS)

    Contillo, Adriano; Di Domenico, Giovanni; Cardarelli, Paolo; Gambaccini, Mauro; Taibi, Angelo

    2016-01-01

    Purpose: Dual-energy image subtraction represents a useful tool to improve the detectability of small lesions, especially in dense breasts. A feature it shares with all x-ray imaging techniques is the appearance of fluctuations in the texture of the background, which can obscure the visibility of interesting details. The aim of the work is to investigate the main noise sources, in order to create a better performing subtraction mechanism. In particular, the structural noise cancellation was achieved by means of a suitable extension of the dual-energy algorithm. Methods: The effect of the cancellation procedure was tested on an analytical simulation of a target with varying structural composition. Subsequently, the subtraction algorithm was also applied to a set of actual radiographs of a breast phantom exhibiting a nonuniform background pattern. The background power spectra of the outcomes were computed and compared to the ones obtained from a standard subtraction algorithm. Results: The comparison between the standard and the proposed cancellations showed an overall suppression of the magnitudes of the spectra, as well as a flattening of the frequency dependence of the structural component of the noise. Conclusions: The proposed subtraction procedure provides an effective cancellation of the residual background fluctuations. When combined with the polychromatic correction already described in a companion publication, it results in a high performing dual-energy subtraction scheme for commercial mammography units.

  2. A novel approach to background subtraction in contrast-enhanced dual-energy digital mammography with commercially available mammography devices: Noise minimization

    Energy Technology Data Exchange (ETDEWEB)

    Contillo, Adriano, E-mail: contillo@fe.infn.it; Di Domenico, Giovanni; Cardarelli, Paolo; Gambaccini, Mauro; Taibi, Angelo [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, I-44122 Ferrara (Italy)

    2016-06-15

    Purpose: Dual-energy image subtraction represents a useful tool to improve the detectability of small lesions, especially in dense breasts. A feature it shares with all x-ray imaging techniques is the appearance of fluctuations in the texture of the background, which can obscure the visibility of interesting details. The aim of the work is to investigate the main noise sources, in order to create a better performing subtraction mechanism. In particular, the structural noise cancellation was achieved by means of a suitable extension of the dual-energy algorithm. Methods: The effect of the cancellation procedure was tested on an analytical simulation of a target with varying structural composition. Subsequently, the subtraction algorithm was also applied to a set of actual radiographs of a breast phantom exhibiting a nonuniform background pattern. The background power spectra of the outcomes were computed and compared to the ones obtained from a standard subtraction algorithm. Results: The comparison between the standard and the proposed cancellations showed an overall suppression of the magnitudes of the spectra, as well as a flattening of the frequency dependence of the structural component of the noise. Conclusions: The proposed subtraction procedure provides an effective cancellation of the residual background fluctuations. When combined with the polychromatic correction already described in a companion publication, it results in a high performing dual-energy subtraction scheme for commercial mammography units.

  3. Meeting increased demand for total knee replacement and follow-up: determining optimal follow-up.

    Science.gov (United States)

    Meding, J B; Ritter, M A; Davis, K E; Farris, A

    2013-11-01

    The strain on clinic and surgeon resources resulting from a rise in demand for total knee replacement (TKR) requires reconsideration of when and how often patients need to be seen for follow-up. Surgeons will otherwise require increased paramedical staff or need to limit the number of TKRs they undertake. We reviewed the outcome data of 16 414 primary TKRs undertaken at our centre to determine the time to re-operation for any reason and for specific failure mechanisms. Peak risk years for failure were determined by comparing the conditional probability of failure, the number of failures divided by the total number of TKRs cases, for each year. The median times to failure for the most common failure mechanisms were 4.9 years (interquartile range (IQR) 1.7 to 10.7) for femoral and tibial loosening, 1.9 years (IQR 0.8 to 3.9) for infection, 3.1 years (IQR 1.6 to 5.5) for tibial collapse and 5.6 years (IQR 3.4 to 9.3) for instability. The median time to failure for all revisions was 3.3 years (IQR 1.2 to 8.5), with an overall revision rate of 1.7% (n = 282). Results from our patient population suggest that patients be seen for follow-up at six months, one year, three years, eight years, 12 years, and every five years thereafter. Patients with higher pain in the early post-operative period or high body mass index (≥ 41 kg/m(2)) should be monitored more closely.

  4. Time-resolved imaging of contrast kinetics does not improve performance of follow-up MRA of embolized intracranial aneurysms.

    Science.gov (United States)

    Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

    2012-07-01

    The use of contrast media and the time-resolved imaging of contrast kinetics (TRICKS) technique have some theoretical advantages over time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. We prospectively compared the diagnostic performance of TRICKS and TOF-MRA with digital subtracted angiography (DSA) in the assessment of occlusion of embolized aneurysms. Seventy-two consecutive patients with 72 aneurysms were examined 3 months after embolization. Test characteristics of TOF-MRA and TRICKS were calculated for the detection of residual flow. The results of quantification of flow were compared with weighted kappa. Intraobserver and interobserver reproducibility was determined. The sensitivity of TOF-MRA was 85% (95% CI, 65-96%) and of TRICKS, 89% (95% CI, 70-97%). The specificity of both methods was 91% (95% CI, 79-98%). The accuracy of the flow quantification ranged from 0.76 (TOF-MRA) to 0.83 (TRICKS). There was no significant difference between the methods in the area under the ROC curve regarding both the detection and the quantification of flow. Intraobserver reproducibility was very good with both techniques (kappa, 0.86-0.89). The interobserver reproducibility was moderate for TOF-MRA and very good for TRICKS (kappa, 0.74-0.80). In this study, TOF-MRA and TRICKS presented similar diagnostic performance; therefore, the use of time-resolved contrast-enhanced MRA is not justified in the follow-up of embolized aneurysms.

  5. Impact of femoral artery puncture using digital subtraction angiography and road mapping on vascular and bleeding complications after transfemoral transcatheter aortic valve implantation.

    Science.gov (United States)

    El-Mawardy, Mohamed; Schwarz, Bettina; Landt, Martin; Sulimov, Dmitriy; Kebernik, Julia; Allali, Abdelhakim; Becker, Bjoern; Toelg, Ralph; Richardt, Gert; Abdel-Wahab, Mohamed

    2017-01-20

    The use of large-diameter sheaths carries the risk of significant vascular and bleeding complications after transfemoral transcatheter aortic valve implantation (TAVI). In this analysis, we sought to assess the impact of a modified femoral artery puncture technique using digital subtraction angiography (DSA) and road mapping during transfemoral TAVI on periprocedural vascular and bleeding events. This is a retrospective analysis of transfemoral TAVI patients included in a prospective institutional database. The modified femoral artery puncture technique using DSA-derived road mapping guidance was introduced in October 2012. Before the introduction of this technique, vascular puncture was acquired based on an integration of angiographic data, the bony iliofemoral landmarks and a radiopaque object. Consecutive patients who underwent TAVI with the road mapping technique (RM group, n=160) were compared with consecutive patients who underwent TAVI without road mapping (control group, n=160) prior to its introduction. A standardised strategy of periprocedural anticoagulation was adopted in both groups as well as the use of a single suture-based closure device. All endpoints were defined according to the VARC-2 criteria for event definition. The mean age in the RM group was 80±7.7 years compared to 81±5.9 years in the control group (p=0.19), and females were equally distributed between both groups (63.1% vs. 58.1%, p=0.36). The baseline logistic EuroSCORE was 20.7±14.4% vs. 24.9±15.2% in the RM and control group, respectively (p=0.01). Notably, sheath size was significantly larger in the RM compared to the control group due to the more frequent use of the 20 Fr sheath (23.8% vs. 1.8%, proad map group but did not reach statistical significance (8.1% vs. 13.8%, p=0.1). Other forms of vascular and bleeding complications as well as all-cause mortality were comparable in both groups. A modified femoral artery puncture technique using DSA and road mapping was associated

  6. Carbon dioxide (CO{sub 2}) digital subtraction angiography. Evaluation of a new delivery system; Angiografia con anidride carbonica. Nuovo sistema di iniezione

    Energy Technology Data Exchange (ETDEWEB)

    Nicolini, A.; Lovaria, A.; Meregaglia, D. [Ospedale Maggiore IRCCS Policlinico, Milan (Italy). Dipt. di Scienze Radiologiche; Palatresi, S. [Ospedale Maggiore IRCCS Policlinico, Milan (Italy). Ist. di Clinica Medica Generale e Terapia Medica

    2000-02-01

    Purpose of this work is to evaluate the usefulness of a new carbon dioxide (CO{sub 2}) intravascular injection system in digital subtraction angiography. March 1998 to May 1999, 39 patients were submitted to digital subtraction angiography with CO{sub 2} injection by a new delivery system, CO{sub 2}-Angio set, OptiMed, Ettingen, Germany. The patients were 29 men and 10 women, whose age ranged 32 to 76 (mean: 47), 18 of them with absolute or relative contraindications to iodinated contrast media and 6 with poor diagnostic findings at previous conventional angiography. CO{sub 2} was used for comparison with iodinated contrast agents in 4 patients. It was studied the following vascular districts: renal arteries in 9 patients, portal vein in 18, lower limb arteries in 7, upper limb veins in 4. In 1 patient CO{sub 2} angiography was carried out for the diagnosis and interventional treatment, by transcatheter embolization, of a postbioptic arteriovenous renal fistula. During the procedure, arterial blood pressure, EKG status and oxygen saturation were monitored, and subjective sensations recorded in all patients. CO{sub 2} angiography provided adequate visualization of vascular districts and of abnormal findings in 32 cased (82%), while its results were considered insufficient for correct and complete assessment in 7 cases (18%). CO{sub 2}-Angio set delivery system has proved to be a simple and safe tool, particularly suitable for use in patients at risk for allergic reactions to iodinated contrast agents and in those with renal function impairment. Also, the system can help carry out some interventional procedures such as arteriovenous fistula embolization and trans jugular portosystemic shunting. [Italian] Scopo di questo articolo e' verificare la validita' e l'efficacia di un nuovo sistema di iniezione angiografico per anidride carbonica. Da marzo 1998 a maggio 1999 sono stati sottoposti ad angiografia con anidride carbonica mediante sistema non

  7. The value of gynecologic cancer follow-up

    DEFF Research Database (Denmark)

    Lajer, Henrik; Jensen, Mette B.; Kilsmark, Jannie

    2010-01-01

    that follow-up affects the women's quality of life. CONCLUSIONS:: The main purpose of follow-up after treatment of cancer is improved survival. Our review of the literature showed no evidence of a positive effect on survival in women followed up after primary treatment of endometrial or ovarian cancer......INTRODUCTION:: To explore the extent of evidence-based data and cost-utility of follow-up after primary treatment of endometrial and ovarian cancer, addressing perspectives of technology, organization, economics, and patients. METHODS:: Systematic literature searches according......:: None of the identified studies supported a survival benefit from hospital-based follow-up after completion of primary treatment of endometrial or ovarian cancer. The methods for follow-up were of low technology (gynecologic examination with or without ultrasound examination). Other technologies had...

  8. 29 CFR 99.315 - Audit findings follow-up.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Audit findings follow-up. 99.315 Section 99.315 Labor Office... § 99.315 Audit findings follow-up. (a) General. The auditee is responsible for follow-up and corrective... include the reference numbers the auditor assigns to audit findings under § 99.510(c). Since the summary...

  9. Intra-operative cone beam computed tomography can help avoid reinterventions and reduce CT follow up after infrarenal EVAR.

    Science.gov (United States)

    Törnqvist, P; Dias, N; Sonesson, B; Kristmundsson, T; Resch, T

    2015-04-01

    Re-interventions after endovascular abdominal aortic aneurysm repair (EVAR) are common and therefore a strict imaging follow up protocol is required. The purpose of this study was to evaluate whether cone beam computed tomography (CBCT) can detect intra-operative complications and to compare this with angiography and the 1 month CT follow up (computed tomography angiography [CTA]). Fifty-one patients (44 men) were enrolled in a prospective trial. Patients underwent completion angiography and CBCT during infrarenal EVAR. Contrast was used except when pre-operative renal insufficiency was present or if the maximum contrast dose threshold was reached. CBCT reconstruction included the top of the stent graft to the iliac bifurcation. Endoleaks, kinks, or compressions were recorded. CBCT was technically successful in all patients. Twelve endoleaks were detected on completion digital subtraction angiography (CA). CBCT detected 4/5 type 1 endoleaks, but only one type 2 endoleak. CTA identified eight type 2 endoleaks and one residual type I endoleak. Two cases of stent compression were seen on CA. CBCT revealed five stent compressions and one kink, which resulted in four intra-operative adjunctive manoeuvres. CTA identified all cases of kinks or compressions that were left untreated. Two of them were corrected later. No additional kinks/compressions were found on CTA. Groin closure consisted of 78 fascia sutures, nine cut downs, and 11 percutaneous sutures. Seven femoral artery pseudoaneurysms (<1 cm) were detected on CTA, but no intervention was needed. CA is better than CBCT in detecting and categorizing endoleaks but CBCT (with or without contrast) is better than CA for detection of kinks or stentgraft compression. CTA plus CBCT identified all significant complications noted on the 1 month follow up CTA. The use of intra-operative CA and CBCT could replace early CTA after standard EVAR thus reducing overall radiation and contrast use. Technical development might further

  10. National screening program vs. standardized neurodevelopmental follow-up

    NARCIS (Netherlands)

    Maschke, Cornelia; Ellenrieder, Birte; Hecher, Kurt; Bartmann, Peter

    Background: Long-term follow-up is urgently needed to decide on the consequences of new therapies. Objective: This study assesses the use of a national child development screening program for a follow-up examination of a defined patient group. Patients and methods: Neurodevelopmental outcome of 139

  11. Carcinoembryonic Antigen (CEA) in colorectal cancer follow-up

    NARCIS (Netherlands)

    Verberne, Charlotte

    2016-01-01

    Colorectal cancer follow-up aims to detect recurrent disease as soon as possible, since earlier detection of recurrent disease is associated with greater chances for cure. A part of follow-up is the measurement of Carcinoembryonic Antigen (CEA) in the blood of the patient. This tumor marker is

  12. The follow-up time issue on small roundabouts

    Directory of Open Access Journals (Sweden)

    Janusz WOCH

    2008-01-01

    Full Text Available The follow-up time was investigated. The aim of this analysis was to create a formula that allows the follow-up time calculated using the most important external parameters. The studies were based on empirical data collected at small roundabouts localized on Upper Silesia. The follow-up time is the average time gap between two cars of the minor stream being queued and entered the same major stream gap one behind the other. Follow-up times were measured directly by observing traffic flow. Resulting follow-up times were analyzed to determine their dependence on parameters such as intersection layout, roundabouts diameter and left visibility. These parameters were tested using the conventional calculation method (regression analysis. The dependence of follow-up time was then integrated into the own capacity estimation method for small roundabouts localized on urban areas. One of the biggest advantages this dependence is that capacity and traffic flow on small roundabouts can be determined reliably and appropriately for actual situations. The new follow-up time values for all range of external diameters of small roundabout 26 (22 – 40 m have been presented in this article.

  13. Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction

    International Nuclear Information System (INIS)

    Kimura, Hiroyuki; Kanda, Shigenobu; Tanaka, Takemasa

    2002-01-01

    The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow-up examination could be assessed quantitatively. It is suggested that geometric

  14. The Danish Cerebral Palsy Follow-up Program

    DEFF Research Database (Denmark)

    Rasmussen, Helle Mätzke; Nordbye-Nielsen, Kirsten; Møller-Madsen, Bjarne

    2016-01-01

    AIM OF DATABASE: The Danish Cerebral Palsy Follow-up Program is a combined follow-up program and national clinical quality database that aims to monitor and improve the quality of health care for children with cerebral palsy (CP). STUDY POPULATION: The database includes children with CP aged 0...... indicators in three of five regions in Denmark comprising 432 children with CP, corresponding to a coverage of 82% of the expected population. CONCLUSION: The Danish Cerebral Palsy Follow-up Program is currently under development as a national clinical quality database in Denmark. The database holds...

  15. Follow-up Medical Care After Cancer Treatment

    Science.gov (United States)

    ... Data Conducting Clinical Trials Statistical Tools and Data Terminology Resources NCI Data Catalog Cryo-EM NCI's Role ... Questions to Ask About Cancer Research Follow-Up Medical Care Once you’re done with cancer treatment, ...

  16. Post-Discharge Follow-Up Visits and Hospital Utilization

    Data.gov (United States)

    U.S. Department of Health & Human Services — Analysis reported in Post-Discharge Follow-Up Visits and Hospital Utilization by Medicare Patients, 2007-2010, published in Volume 4, Issue 2 of Medicare and...

  17. CT angiography for one-year follow-up of intracranial aneurysms treated with the WEB device: Utility in evaluating aneurysm occlusion and WEB compression at one year.

    Science.gov (United States)

    Raoult, Hélène; Eugène, François; Le Bras, Anthony; Mineur, Géraldine; Carsin-Nicol, Béatrice; Ferré, Jean-Christophe; Gauvrit, Jean-Yves

    2018-03-07

    The WEB is an innovative flow disruption device for cerebral aneurysm embolization with rapidly expanding indications. Our purpose was to evaluate the diagnostic performance of computed tomography angiography (CTA) at 1-year follow-up of aneurysms treated with the WEB. Between April 2014 and May 2016, the study prospectively included patients treated with the WEB at our institution, and followed up within 24hours by CTA and at 1year by CTA, time-of-flight magnetic resonance angiography (TOF MRA) and digital subtraction angiography (DSA). The diagnostic quality of imaging data was assessed based on the confidence index, artifacts, and WEB shape depiction. The imaging diagnostic performance was assessed using 3 criteria at 1year: aneurysm occlusion status and worsening, and WEB shape compression. Interobserver and intermodality agreement was determined by calculating κ values. The study ultimately included 16 patients (9 women, mean age 53±7.6years). CTA quality confidence was scored as 2/2, artifacts 0.4/2 and WEB shape depiction 1.9/2, superior to TOF MRA for the latter two criteria. Aneurysm occlusion was adequate in 93.7% of patients, with CTA showing excellent interobserver reproducibility and agreement with DSA on a 4-grade scale (κ=1.00), while TOF MRA yielded good reproducibility (κ=0.76) and agreement with DSA (κ=0.69). CTA also identified aneurysm occlusion worsening (43.7%) and WEB compression (81.2%) in excellent agreement with DSA (κ=0.85 and 1.00). CTA is a reproducible and reliable technique for the follow-up of aneurysms treated with the WEB device. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  18. Internet of things and bariatric surgery follow-up: Comparative study of standard and IoT follow-up.

    Science.gov (United States)

    Vilallonga, Ramon; Lecube, Albert; Fort, José Manuel; Boleko, Maria Angeles; Hidalgo, Marta; Armengol, Manel

    2013-09-01

    Follow-up of obese patient is difficult. There is no literature related to patient follow-up that incorporates the concept of Internet of Things (IoT), use of WiFi, Internet, or portable devices for this purpose. This prospective observational study commenced in June 2011. Patients were prospectively offered to participate in the IoT study group, in which they received a WiFi scale (Withing®, Paris) that provides instant WiFi data to the patient and surgeon. Other patients were admitted to the standard follow-up group at the outpatient clinic. A total of 33 patients were included in our study (ten in the IoT group). Twelve patients did not have WiFi at home, ten lacked of computer knowledge, and seven preferred standard for follow-up. All patients underwent different surgical procedures. There were no complications. Excess weight loss (EWL) was similar in both groups. More than 90% of patients were satisfied. In the IoT group, patients considered it valuable in saving time, and considered seeing their evolution graphics extremely motivating. IoT technology can monitor medical parameters remotely and collect data. A WiFi scale can facilitate preoperative and follow-up. Standard follow-up in a classical outpatient clinic setting with the surgeon was preferred globally.

  19. Nonimaging aspects of follow-up in breast cancer reconstruction.

    Science.gov (United States)

    Wood, W C

    1991-09-01

    Follow-up of patients with breast cancer is directed to the early detection of recurrent or metastatic disease and the detection of new primary breast cancer. The survival benefit of early detection is limited to some patients with local failure or new primary tumors. That imaging is not used in follow-up of patients who have had breast cancer reconstruction is related to possible interference with this putative benefit by the reconstructive procedure. Such follow-up is accomplished by the patient's own surveillance, clinical examination, and laboratory testing supplemented by imaging studies. Clinical follow-up trials of women who have undergone breast reconstructive surgery show no evidence that locally recurrent breast carcinoma is masked when compared with follow-up of women who did not undergo reconstructive procedures. Reshaping of the contralateral breast to match the reconstructed breast introduces the possibility of interference with palpation as well as mammographic distortion in some women. This is an uncommon practical problem except when complicated by fat necrosis.

  20. Follow-up care of children suffered from burns

    Directory of Open Access Journals (Sweden)

    Konstantin Aleksandrovich Afonichev

    2015-03-01

    Full Text Available Outcomes of III-VI AB degree burns in children,regardless of the nature of treatment in the acute andrecovery period, are the development of scar contractures and deformities of the joints. However, thecorrect organization of follow-up care and rehabilitation treatment can significantly reduce the severity and facilitates the full recovery of the affected segment. Based on the analysis of their own material, the author defines the early stage of rehabilitation in these patients before full maturation of scar tissue or before the formation of functionally significant joint contractures, and later period, when there are indications for surgical rehabilitation. In the early period, follow-up care is recommended in 1 month after discharge and then on a quarterly basis, and with the appearance of deformities - at least once in 2 months. At the2nd stage of rehabilitation, older children and children of secondary school age are subject to follow-up care at least 1 time per year of primary school age - atleast once in 6 months, preschool children - every3 months. The proposed assessment of scar tissuehelps to determine the terms of follow-up care. Usingthis scheme of follow-up care and appropriate treatment allowed the author to obtain excellent and goodresults in 87-90 % of cases at the stages of rehabilitaion.

  1. Peritoneal inclusion cysts: Changes on follow-up ultrasonography

    International Nuclear Information System (INIS)

    Kim, Jung Sik; Lee, Jin Hee; Lee, Hee Jung; Lee, Sung Moon; Woo, Seong Ku

    2003-01-01

    To evaluate the volume change of peritoneal inclusion cysts on the follow-up ultrasonography (US). From March 1995 to May 1999, thirty seven women with ultrasonographically diagnosed peritoneal inclusion cysts were included in this study. Six patients underwent surgery for several reasons. Follow-up ultrasonography was performed 70-456 days (mean=191 days) after initial US examination in 12 of the remaining 31 patient with no further treatment. US was performed with a 3.5 or 4 MHz transabdominal probe in all 18 patients who underwent either surgery or follow-up US, and additional tranvaginal US examination using a 5-7 MHz probe in 15 of 18 patients. The volume change of the cysts was recorded for each US examination. Three cysts (25%) (volume=170 cm 3 , 61 cm 3 , and 38 cm 3 , respectively) were completely resolved on the follow-up US while the other nine cysts showed a decreased volume in seven patients (58%) and increased volume in two patients (17%). Spontaneous regression of peritoneal inclusion cysts is more common than it is believed to be, and ultrasonography may be a useful follow-up examination for peritoneal inclusion cysts.

  2. Radionuclide identification using subtractive clustering method

    International Nuclear Information System (INIS)

    Farias, Marcos Santana; Mourelle, Luiza de Macedo

    2011-01-01

    Radionuclide identification is crucial to planning protective measures in emergency situations. This paper presents the application of a method for a classification system of radioactive elements with a fast and efficient response. To achieve this goal is proposed the application of subtractive clustering algorithm. The proposed application can be implemented in reconfigurable hardware, a flexible medium to implement digital hardware circuits. (author)

  3. Automatic dipole subtraction

    International Nuclear Information System (INIS)

    Hasegawa, K.

    2008-01-01

    The Catani-Seymour dipole subtraction is a general procedure to treat infrared divergences in real emission processes at next-to-leading order in QCD. We automatized the procedure in a computer code. The code is useful especially for the processes with many parton legs. In this talk, we first explain the algorithm of the dipole subtraction and the whole structure of our code. After that we show the results for some processes where the infrared divergences of real emission processes are subtracted. (author)

  4. Course of disease and follow-up in breast cancer

    International Nuclear Information System (INIS)

    Ebner, F.; Hackl, H.; Hoermann, M.; Schneider, G.

    1986-01-01

    Besides individual care, regular follow-up studies in breast cancer patients have different aims, relative to different tumor stages at presentation. In early stages emphasis has to be laid on detection of loco-regional recurrences, which will not reduce overall survival if diagnosed and treated early. In addition, treatment effects and changes in the activity of disease are evaluated. Radiographic studies for detection of distant metastases are justified if followed by proper treatment. Early diagnosis of cancer of the opposite breast and of such cancers that are associated with breast cancer (colon, ovaries, endometrium) is imperative. The aim of a regular follow-up in more advanced tumor stages is to monitor the extent of disease and to prevent complications (e.g. fractures, spinal cord compression). In familial breast cancer first degree relatives should be included in the follow-up plan. The patient's psychosocial needs, even if not verbalized, should not be neglected. (Author)

  5. Follow up of Graves' Opthalmopathy after radioiodine therapy

    International Nuclear Information System (INIS)

    Miah, M.S.R.; Paul, A. K.; Rahman, H.A.

    2002-01-01

    Graves' ophthalmopathy may first appear or worsen during or after treatment for hyperthyroidism. We followed up 158 Graves' hyperthyroid patients treated with radioiodine of which 49 had Grave's' ophthalmopathy during presentation in Nuclear Medicine Centre, Khulna during the period from 1995 to 2000. The aim of our study is to see the effect of radioiodine in Graves' ophthalmopathy. All the patients received radioiodine at fixed dose regime ranged from 7 mCi to 12 mCi. The duration of follow up was at least 12 months Graves' ophthalmopathy patients, 4 (4/49 i.e., 8.2%) showed exaggeration of ophthalmopathy and the rest (45/49 i.e., 91.8%) remained unchanged. None of ophthalmopathy developed among any of Graves' hyperthyroid or disappeared after radioiodine treatment during follow up period. From the study we concluded that eye changes in Graves' hyperthyroidism remain unchanged or exaggerated after radioiodine therapy and needs ophthalmologist care.(author)

  6. Esophageal atresia: long-term interdisciplinary follow-up

    Directory of Open Access Journals (Sweden)

    Lidia B. Giúdici

    2016-07-01

    Full Text Available Background: We provide protocolized interdisciplinary follow-up to babies born with Esophageal Atresia (EA. There are few reports in Argentina about follow-up of EA patients.Objective: To describe outcomes in follow-up of EA patients at 1, 3 and 6 years old and to compare outcomes at age 1 with those at age 6.Methods: Prospective, longitudinal, analytic study of the cohort of babies born with EA, admitted to the follow-up program from 11/01/03 to 10/31/14. Follow-up includes: growth (weight > 10th centile, WHO, neurology-psychomotor development, audiology, vision, genetic, mental health, surgical reintervention, phonostomatology, language, pulmonology, re-hospitalization for clinical causes, lost to follow-up. Outcomes were described at age 1, 3 and 6. We included all EA patients who had reached age 1 at the start of this study.Results: 27 babies were admitted; 30% had long-gap EA; 18% presented VACTERL association; 23 children met inclusion criteria. Genetics  was assessed in 18 newborns (78%; a chromosomal map was performed in 11 babies; 3 had an abnormal karyotype. Mental health: 5/14 of the assessed children showed problems. Phonostomatology: 11 newborns checked (6 required treatment, 4 recovered at age 1. Pulmonologist evaluated 18 babies (7 with recurrent wheezing, 6 with moderate tracheomalacia. Gastroenterology and endoscopy: 80% presented gastroesophageal reflux (GER grade 3-4, and 50% showed a pathologic pHmetry. Lost to follow-up: age 1, 2 (8%; age 3, 3 (17%; age 6, 3 (23%. Normal outcomes observed are the following. Age 1 – growth: 81%; neurologic-psychomotor developmental index (NPDI: 76%; audiology: 95%; vision: 85%; language: 62%; re-hospitalization for clinical causes: 38%; surgical reinterventions: 47%. Age 3 – growth: 78%; NPDI: 50%; audiology: 93%; vision: 93%; language: 43%; re-hospitalization: 35%; surgical reinterventions: 14%. Age 6 – growth: 50%; NPDI: 30%; audiology: 90%; vision: 40%; language: 50%; re

  7. Exercise-Induced Ventricular Fibrillation: Seven Years Follow-Up

    Directory of Open Access Journals (Sweden)

    Gökmen Gemici

    2011-11-01

    Full Text Available We present a 7-year follow-up of a 55-year-old male who experienced ventricular fibrillation during the recovery period of exercise testing and refused implantation of an ICD. Normal left ventricular systolic function was found on echocardiographic examination, and coronary angiography revealed only a side branch disease with a vessel diameter of less than 2 millimeters. The patient was discharged on metoprolol and ASA in addition to his previous treatment with lisinopril and simvastatin. Outpatient cardiac evaluation by repeated 24-hour ECG monitorizations (Holter revealed normal findings. On follow up visits every six months for the past seven years, the patient was found to be asymptomatic.

  8. Group anxiety management: effectiveness, perceived helpfulness and follow-up.

    Science.gov (United States)

    Cadbury, S; Childs-Clark, A; Sandhu, S

    1990-05-01

    An evaluation was conducted on out-patient cognitive-behavioural anxiety management groups. Twenty-nine clients assessed before and after the group and at three-month follow-up showed significant improvement on self-report measures. A further follow-up on 21 clients, conducted by an independent assessor at an average of 11 months, showed greater improvement with time. Clients also rated how helpful they had found non-specific therapeutic factors, and specific anxiety management techniques. 'Universality' was the most helpful non-specific factor, and 'the explanation of anxiety' was the most helpful technique.

  9. Barrett's esophagus. Diagnosis, follow-up and treatment

    DEFF Research Database (Denmark)

    Bremholm, Lasse; Funch-Jensen, Peter; Eriksen, Jan

    2012-01-01

    gastroesophageal junction. The extent of the endoscopic findings is described by the Prague classification. The metaplasia is histologically confirmed by the presence of intestinal metaplasia. The diagnosis of BE can only be made by a combined macroscopic and microscopic examination. The histological description...... and it is not recommended outside controlled studies. Treatment of high grade dysplasia and carcinoma in situ is handled in departments treating esophageal cancer. Follow-up with endoscopy and biopsy can be offered. Follow-up endoscopy with biopsy can only be recommended after thorough information to the patients...

  10. Danish offshore wind. Key environmental issues - a follow-up

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    This follow-up to the Danish environmental monitoring programme on large-scale offshore wind power builds on the result of the former programme of 2006 and focuses on updated knowledge on harbour porpoises, water birds and fish communities, and on the cumulative effects of wind farms. The scientific quality of the projects in this follow-up has been assessed by experts from the International Advisory Panel of Experts on Marine Ecology (IAPEME), who have commented on the results in an independent evaluation which is reproduced in this publication. (LN)

  11. Advances in diagnosis and follow-up in kidney cancer

    NARCIS (Netherlands)

    Rioja, Jorge; de La Rosette, Jean J. M. C. H.; Wijkstra, Hessel; Laguna, M. Pilar

    2008-01-01

    PURPOSE OF REVIEW: To review the most recent data on preoperative diagnostic methods in kidney cancer and in follow-up and monitoring after ablation therapy. RECENT FINDINGS: Although the role of the percutaneous biopsy in the diagnostics of renal masses has been limited, new data suggest a high

  12. 38 CFR 41.315 - Audit findings follow-up.

    Science.gov (United States)

    2010-07-01

    ... include audit findings from multiple years, it shall include the fiscal year in which the finding... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Audit findings follow-up... (CONTINUED) AUDITS OF STATES, LOCAL GOVERNMENTS, AND NON-PROFIT ORGANIZATIONS Auditees § 41.315 Audit...

  13. Follow-up of conservatively treated sleep apnoea patients

    African Journals Online (AJOL)

    Health of School Children: Treatment of /ntestinal. Helminths and Schistosomiasis (WHO/GDS/IPI/GTD 92.1). Geneva: WHO, 1992. Accepted 17 June 1994. Follow-up of conservatively treated sleep apnoea patients. P. R. Bartel, J. Verster, P. J. Becker. Polysomnograms have been recorded at our laboratory since 1985 for ...

  14. Nimh Treatment Study of ADHD Follow-Up

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-04-01

    Full Text Available The effects of changes in medication use between 14 and 24 months follow-up on effectiveness (symptom ratings and growth (height and weight measures were analyzed, comparing 4 groups of patients, in the Multimodal Treatment Study of ADHD (MTA reported by the MTA Cooperative Group.

  15. Handbook of Exemplary Practices in Placement and Follow-Up.

    Science.gov (United States)

    Mehallis, Mantha Vlahos

    This handbook for teachers, counselors, and administrators presents exemplary practices in the use of job placement and follow-up services based on results of a survey of Florida school districts and community colleges. A description of survey methodology and the survey questionnaire, as well as a statewide profile of Florida exemplary practices…

  16. Factors Associated with Adherence to Follow-up Colposcopy

    Science.gov (United States)

    Fish, Laura J.; Moorman, Patricia G.; Wordlaw-Stintson, Lashawn; Vidal, Adriana; Smith, Jennifer S.; Hoyo, Cathrine

    2013-01-01

    Background: Understanding the gaps in knowledge about human papilloma virus (HPV) infection, transmission, and health consequences and factors associated with the knowledge gap is an essential first step for the development of interventions to improve adherence to follow-up among women with abnormal Pap smears. Purpose: To examine the relationship…

  17. Immunological follow-up of hydatid cyst cases

    Directory of Open Access Journals (Sweden)

    Bulut Vedat

    2001-01-01

    Full Text Available Hydatid disease is caused by Echinococcus granulosus. In this study, we aimed to investigate the benefit of monitoring cases with hydatid cyst by means of immune components in patients in a long-term follow-up after surgery. Eighty-four preoperative and postoperative serum samples from 14 cases undergoing surgery for hydatid disease were evaluated in terms of immune parameters, such as total and specific IgE, IgG, IgM, IgA and complement. Total and specific IgE were determined by ELISA. Specific IgG levels were measured by indirect hemaglutination.Total IgG, IgM, IgA and complement (C3 and C4 were detected by nephelometry. Imaging studies were also carried out during the follow-up. In none of the patients hydatid cysts were detected during the follow-up. Total IgE levels in the sera of the patients decreased to normal six months after surgery. Although specific IgE against echinococcal antigens decreased one year after operation, levels were still significantly high. There were no changes in the levels of anti-Echinococcus IgG and total IgG in follow-up period. Additionally, other parameters, such as IgA, IgM, C3 and C4, were not affected.

  18. Refractive surgery for accommodative esotropia: 5-year follow-up.

    Science.gov (United States)

    Magli, Adriano; Forte, Raimondo; Gallo, Flavio; Carelli, Roberta

    2014-02-01

    To assess the long-term effectiveness and safety of refractive surgery with LASIK or photorefractive keratectomy (PRK) for treating accommodative esotropia in adults. All patients with accommodative esotropia treated with LASIK or PRK until December 2007 and with a minimum follow-up of 5 years were retrospectively included. LASIK was performed on 44 eyes of 22 patients (12 women, 10 men; mean age: 22.7 ± 2.9 years). Mean postoperative follow-up was 62.1 ± 3.2 months. PRK was performed on 16 eyes of 8 patients (4 women, 4 men; mean age: 23.7 ± 1.7 years). Mean postoperative follow-up was 61.3 ± 2.8 months. At the 5-year follow-up, the mean cycloplegic refraction was more hyperopic in the PRK group (0.3 ± 0.8 vs 0.06 ± 0.3 diopters, P = .01). Correction of esotropia to esophoria or orthotropia was present in 21 patients (95.4%) treated with LASIK and in all patients treated with PRK. Both LASIK and PRK were effective in the long-term reduction of accommodative esotropia. Copyright 2014, SLACK Incorporated.

  19. Women's experiences of a follow up childbearing journey with ...

    African Journals Online (AJOL)

    The purpose of this study was to describe and analyse the lived experiences of the follow up journey of a pregnant woman by listening to the voices of women as they reflect on their journey. A qualitative, descriptive and contextual design was used to examine into each woman's experience of her world from pregnancy to ...

  20. [Follow-up and treatment outcome of early anorexia nervosa].

    Science.gov (United States)

    Schulze, U; Neudörfl, A; Krill, A; Warnke, A; Remschmidt, H; Herpertz-Dahlmann, B

    1997-03-01

    In a two-center follow-up study on the early-onset form of anorexia nervosa, we reexamined 43 (74%) of 58 former patients who had developed anorexia nervosa at the age of 13 years or younger. In addition to make a standardized assessment of the eating disorder at follow-up we assessed psychiatric comorbidity with a structured interview based on the criteria of DSM-III-R and ICD-10. After an average follow-up period of 6.8 years, 8 (18%) of our former patients had an eating disorder not otherwise specified (EDNOS) and 4 (9%) still suffered from anorexia nervosa. 5 (11%) of the subjects had developed bulimia nervosa. In 3 cases (7%) we found both syndromes. 12 (28%) of our former patients had an additional psychiatric disorder. The results of our study indicate that the quality of outcome in patients with an early-onset form of anorexia nervosa does not differ from that in individuals with a later manifestation of the eating disorder. Factors of prognostic relevance were the existence of an eating disorder during the first year of life and the duration of the follow-up period.

  1. Eight to ten years follow-up after carotid endarterectomy

    DEFF Research Database (Denmark)

    Knudsen Rathenborg, Lisbet; Sillesen, H; Schroeder, T

    1990-01-01

    Follow-up information was obtained on 185 patients who consecutively underwent carotid endarterectomy eight to ten years previously. Doppler ultrasound examination was performed in 59 patients who were still alive and living within 100 miles of the hospital. Using lifetable analysis, the annual r...

  2. Challenges of loss to follow-up in tuberculosis research

    DEFF Research Database (Denmark)

    Nissen, Thomas N; Rose, Michala V; Kimaro, Godfather

    2012-01-01

    In studies evaluating methods for diagnosing tuberculosis (TB), follow-up to verify the presence or absence of active TB is crucial and high dropout rates may significantly affect the validity of the results. In a study assessing the diagnostic performance of the QuantiFERON®-TB Gold In-Tube test...

  3. Nurse-Initiated Telephone Follow Up after Ureteroscopic Stone Surgery.

    Science.gov (United States)

    Tackitt, Helen M; Eaton, Samuel H; Lentz, Aaron C

    2016-01-01

    This article presents findings of a quality improvement (QI) project using the DMAIC (define, measure, analyze, improve, and control) model designed to decrease the rate of emergency department (ED) visits and nurse advice line calls after ureteroscopic stone surgery. Results indicated that nurse-initiated follow- up phone calls can decrease ED visits.

  4. A Follow-Up Study of the Deaf.

    Science.gov (United States)

    Reich, P. A.; Reich, C. M.

    Followed up through interviews and questionnaires were 278 former students, average age 28 years, of two residential schools and one day school for the deaf in Ontario. Data was collected on the degree of hearing loss, use of a hearing aid, educational and occupational history, social integration, methods of communication, and attitudes toward…

  5. Loss to Follow-Up: Issues and Recommendations

    Science.gov (United States)

    Hoffman, Jeff; Munoz, Karen F.; Bradham, Tamala S.; Nelson, Lauri

    2011-01-01

    State coordinators of early hearing detection and intervention (EHDI) programs completed a strengths, weaknesses, opportunities, and threats, or SWOT, analysis that examined 12 areas within state EHDI programs. Related to how EHDI programs address loss to follow-up, 47 coordinators responded with 277 items, and themes were identified in each…

  6. MRI of penile fracture: diagnosis and therapeutic follow-up

    International Nuclear Information System (INIS)

    Uder, Michael; Gohl, Dietrich; Takahashi, Masahide; Kramann, Bernhard; Schneider, Guenther

    2002-01-01

    A rupture of corpus cavernosum (CC) is a rare injury of the erect penis. The present study describes the role of MRI for diagnosis and follow-up of this injury. Four patients with clinically suspected acute penile fractures underwent MRI. Imaging findings were confirmed at surgery. In three patients, follow-up MRI was also available at 1, 6 and 16 weeks after surgical repair. In all patients pre-contrast T1-weighted images (T1WI) clearly disclosed ruptures of CC, which depicted as discontinuity of low signal intensity of the tunica albuginea (TA). Concomitant subcutaneous haematoma were well visualised both on T1-weighted (T1WI) and T2-weighted images, whereas haematoma in CC were optimally demonstrated on contrast-enhanced T1WI. On follow-up MRI all fractures presented similar healing process. Shortly after the repair, the tunical suture showed an increase in signal intensity on pre-contrast T1WI and was strongly enhanced with the administration of contrast material. Then the tear site gradually recovered low signal intensity on all spin-echo sequences by 4 months after surgery. These serial findings may suggest the formation of vascularised granulation tissue during cicatrisation. Magnetic resonance imaging is of great value for the diagnosis and follow-up in patients with penile fracture. (orig.)

  7. A formula for continued improvement: Audit follow-up

    International Nuclear Information System (INIS)

    Maday, J.H. Jr.

    1989-10-01

    In his book Management Audits, Allan J. Sayle states, ''QA standards stipulate that corrective action, required as a result of performing an audit, be followed up and closed out. There would, indeed, be little point in performing audits, requiring corrective action, or having a QA system at all if the auditee knows that the auditor will never verify that the corrective action has been efficaciously implemented.'' The QA auditor has an obligation to include follow-up in the overall audit planning. All too often the auditor will go to great lengths to plan and perform an audit only to have a recurring finding in the next audit. The proposed corrective action was only promissory and was not designed to stop the problem from recurring or to identify its root cause. Auditors do a disservice to the overall QA program and particularly to the customer when they fail to follow up and verify that an audit corrective action has been effectively implemented. In this paper, the techniques used by the quality assurance auditors at the Pacific Northwest Laboratory (PNL) will be presented. Although PNL is a research and development laboratory, the techniques outlined in this paper could be applied to any industry conducting quality assurance audits. Most important, they provide a formula for continued improvement by assuring that audit follow-up is timely, meaningful, and permanent

  8. Analytical framework and tool kit for SEA follow-up

    International Nuclear Information System (INIS)

    Nilsson, Mans; Wiklund, Hans; Finnveden, Goeran; Jonsson, Daniel K.; Lundberg, Kristina; Tyskeng, Sara; Wallgren, Oskar

    2009-01-01

    Most Strategic Environmental Assessment (SEA) research and applications have so far neglected the ex post stages of the process, also called SEA follow-up. Tool kits and methodological frameworks for engaging effectively with SEA follow-up have been conspicuously missing. In particular, little has so far been learned from the much more mature evaluation literature although many aspects are similar. This paper provides an analytical framework and tool kit for SEA follow-up. It is based on insights and tools developed within programme evaluation and environmental systems analysis. It is also grounded in empirical studies into real planning and programming practices at the regional level, but should have relevance for SEA processes at all levels. The purpose of the framework is to promote a learning-oriented and integrated use of SEA follow-up in strategic decision making. It helps to identify appropriate tools and their use in the process, and to systematise the use of available data and knowledge across the planning organization and process. It distinguishes three stages in follow-up: scoping, analysis and learning, identifies the key functions and demonstrates the informational linkages to the strategic decision-making process. The associated tool kit includes specific analytical and deliberative tools. Many of these are applicable also ex ante, but are then used in a predictive mode rather than on the basis of real data. The analytical element of the framework is organized on the basis of programme theory and 'DPSIR' tools. The paper discusses three issues in the application of the framework: understanding the integration of organizations and knowledge; understanding planners' questions and analytical requirements; and understanding interests, incentives and reluctance to evaluate

  9. Follow-up of Antihypertensive Therapy Improves Blood Pressure Control: Results of HYT (HYperTension survey) Follow-up.

    Science.gov (United States)

    Fici, F; Seravalle, G; Koylan, N; Nalbantgil, I; Cagla, N; Korkut, Y; Quarti-Trevano, F; Makel, W; Grassi, G

    2017-09-01

    Although improved during the past few years, blood pressure control remains sub optimal. The impact of follow-up assessment on blood pressure control was evaluated in a group of patients of the HYT (HYperTension survey), treated with a combination of different dihydropyridine calcium-channel blockers (CCBs regimen) and inhibitors of renin-angiotensin-aldosterone system (RAAS) and with uncontrolled blood pressure. This was obtained assessing (a) the rate of blood pressure control at 3 and 6 months of follow-up in the whole group of patients, (b) the rate of blood pressure control and the average blood pressure values in subjects treated with different DHP-CCBs regimen. From the 4993 patients with uncontrolled blood pressure, (BP ≥ 140/90 or ≥140/85 in patients with diabetes), 3729 (mean age 61.2 ± 11.5 years), maintained CCBs regimen combined wih RAAS blockers and were evaluated at 3 and 6 months follow-up. At each visit BP (semiautomatic device, Omron-M6, 3 measurements), heart rate, adverse events and treatment persistence were collected. At 1st and 2nd follow-up the rate of controlled BP was 63.5 and 72.8% respectively (p blood pressure control; (b) there is no significant difference in the antihypertensive effect between different CCBs regimen; (c) lipophilic CCBs induce less ankle edema.

  10. Digital radiography

    International Nuclear Information System (INIS)

    Brody, W.R.

    1984-01-01

    Digital Radiography begins with an orderly introduction to the fundamental concepts of digital imaging. The entire X-ray digital imagining system is described, from an overall characterization of image quality to specific components required for a digital radiographic system. Because subtraction is central to digital radiographic systems, the author details the use of various subtraction methods for image enhancement. Complex concepts are illustrated with numerous examples and presented in terms that can readily be understood by physicians without an advanced mathematics background. The second part of the book discusses implementations and applications of digital imagining systems based on area and scanned detector technologies. This section includes thorough coverage of digital fluoroscopy, scanned projection radiography, and film-based digital imaging systems, and features a state-of-the-art synopsis of the applications of digital subtraction angiography. The book concludes with a timely assessment of anticipated technological advances

  11. CT follow-up of conservatively treated lumbar disc herniation

    International Nuclear Information System (INIS)

    Schumacher, M.; Fischer, R.; Thoden, U.

    1990-01-01

    A CT study was carried out on 43 patients with low back pain and sciatica who were treated conservatively. They were followed up for over 20 months (mean) clinically and monitored by CT before and after treatment. Initially, 38 of them had herniation and 5 had protrusion of the disc. At the time of follow-up only 24 of the initial 40 patients still had neurological deficits. In 76.7% of the patients CT showed an improvement (clear regression in 15 patients, moderate decrease in 18 patients). A favourable tendency towards regression was observed in disc herniation at the L5-S1 level and in cases showing sequestration. The prognosis was unfavourable in herniations at higher levels than L5-S1 and in lateral herniation reaching the intervertebral foramen. (orig.) [de

  12. [Laparoscopic management of ureteroileal stenosis: Long term follow up.

    Science.gov (United States)

    Emiliani, Esteban; Gavrilov, Pavel; Mayordomo, Olga; Salvador, Josep; Palou, Joan; Rosales, Antonio; Villavicencio, Humberto

    2017-05-01

    To describe the laparoscopic approach for uretero-ileal anastomosis strictures and to analyse our long term series. A retrospective review was performed evaluating our series of patients with benign ureteroileal anastomosis strictures treated laparoscopically from 2011 to 2017. Demographics and perioperative data were obtained and analyzed. Complications were described with the Clavien-Dindo classification. The surgical technique was described and a literature review was performed. Eleven procedures were performed in ten patients. Mean blood loss was 180 ml. All the operations were performed laparoscopically without conversion. Mean hospital stay was 10 days (4-23). Early complications were Clavien-Dindo I y II: Two cases of limited anastomosis leakage, one lymphorrea, one paralitic ileum and one accidental descent of the ureteral catheter. Mean follow-up was 56 months (12-179) No late complications have been described. Based on our series with 5 year follow up, the laparoscopic approach for uretero-ileal anastomosis strictures is feasible and safe.

  13. Role of cytology in screening, staging and follow-up

    International Nuclear Information System (INIS)

    Fischnaller, M.

    1986-01-01

    Cytology has become an integral component in the battery of diagnostic tools for a rational diagnosis of tumors. When all materials obtainable with sophisticated methods are utilized, almost every pulmonary lesion can be defined micromorphologically. In urgent cases instant staining techniques will permit a 'stat diagnosis'. The characterization of a tumor cell by cytology with accurate typing and grading offers preliminary information for subsequent staging efforts. Bronchial cancer may be both of the single-cell and of the mixed-cell type with the more aggressive cell elements determining the metastasising potential and prognosis. Sampling for cytology is devoid of risks and does not make any special demands on the patients; it can safely be repeated for follow-up studies; it helps to detect tumor regrowths or secondaries at an early stage during postoperative follow-up programs and to monitor treatment-related cellular changes. (Author)

  14. Treatment of craniopharyngioma estimated by follow-up CT

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, T.; Ito, H.; Aizumi, S.; Yamamoto, S.; (Kanazawa Univ. (Japan). School of Medicine)

    1981-12-01

    Follow-up CT scans were taken from 12 cases of craniopharyngiomas after various treatment. Preoperative CT findings of craniopharyngiomas could be classified into three types. Type 1 was a non-enhanced or a thinly ring-like enhanced large cystic mass. Type 2 was a thickly enhanced large cystic mass with small solid mass. Type 3 was a large solid mass. Postoperative follow-up CT findings were as follows: Type 1 had a favorable postoperative course because the tumor tissues of the thin cystic wall seemed to collapse only with the procedure of cystic fluid aspiration. Recurrence frequently took place in patients of Type 2 and 3 if the tumor couldn't be radically removed or radiotherapy was not given after partial resection. Radiotherapy was most effective in these cases.

  15. Treatment of craniopharyngioma estimated by follow-up CT

    International Nuclear Information System (INIS)

    Kubota, Toshihiko; Ito, Haruhide; Aizumi, Shinichi; Yamamoto, Shinjiro

    1981-01-01

    Follow-up CT scans were taken from 12 cases of craniopharyngiomas after various treatment. Preoperative CT findings of craniopharyngiomas could be classified into three types. Type 1 was a non-enhanced or a thinly ring-like enhanced large cystic mass. Type 2 was a thickly enhanced large cystic mass with small solid mass. Type 3 was a large solid mass. Postoperative follow-up CT findings were as follows: Type 1 had a favorable postoperative course because the tumor tissues of the thin cystic wall seemed to collapse only with the procedure of cystic fluid aspiration. Recurrence frequently took place in patients of Type 2 and 3 if the tumor couldn't be radically removed or radiotherapy was not given after partial resection. Radiotherapy was most effective in these cases. (author)

  16. Electronic Whiteboards and Intensive Care Unit follow up

    DEFF Research Database (Denmark)

    Østergaard, Kija Lin; Brandrup, Morten

    -ended dry-erase whiteboard (make-up-your-own-sentences). In conclusion the primary feature in the two subjects is to optimize communication/collaboration and information between ICU and general wards in the transition. To make it a long term solution the content of such a support would need involvement...... of the end-users in the design process (Participatory Design). Hence these two findings, this review is setting the stage for further research on how electronic whiteboards can support the initial follow up when patients are transferred from an ICU to a general ward.......This paper is reviewing the existing literature on Intensive Care Unit (ICU) Outreach, in-hospital follow up 24 hours after the transition to a general ward from an ICU. It also touches upon the use of Electronic Whiteboards in a hospital setting and how the electronic whiteboards might support...

  17. [Follow-up of newborns with hypoxic-ischaemic encephalopathy].

    Science.gov (United States)

    Martínez-Biarge, M; Blanco, D; García-Alix, A; Salas, S

    2014-07-01

    Hypothermia treatment for newborn infants with hypoxic-ischemic encephalopathy reduces the number of neonates who die or have permanent neurological deficits. Although this therapy is now standard of care, neonatal hypoxic-ischaemic encephalopathy still has a significant impact on the child's neurodevelopment and quality of life. Infants with hypoxic-ischaemic encephalopathy should be enrolled in multidisciplinary follow-up programs in order to detect impairments, to initiate early intervention, and to provide counselling and support for families. This article describes the main neurodevelopmental outcomes after term neonatal hypoxic-ischaemic encephalopathy. We offer recommendations for follow-up based on the infant's clinical condition and other prognostic indicators, mainly neonatal neuroimaging. Other aspects, such as palliative care and medico-legal issues, are also briefly discussed. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  18. From themes to hypotheses: following up with quantitative methods.

    Science.gov (United States)

    Morgan, David L

    2015-06-01

    One important category of mixed-methods research designs consists of quantitative studies that follow up on qualitative research. In this case, the themes that serve as the results from the qualitative methods generate hypotheses for testing through the quantitative methods. That process requires operationalization to translate the concepts from the qualitative themes into quantitative variables. This article illustrates these procedures with examples that range from simple operationalization to the evaluation of complex models. It concludes with an argument for not only following up qualitative work with quantitative studies but also the reverse, and doing so by going beyond integrating methods within single projects to include broader mutual attention from qualitative and quantitative researchers who work in the same field. © The Author(s) 2015.

  19. [Normocalcemic primary hyperparathyroidism: recommendations for management and follow-up].

    Science.gov (United States)

    Martínez Díaz-Guerra, Guillermo; Jódar Gimeno, Esteban; Reyes García, Rebeca; Gómez Sáez, José Manuel; Muñoz-Torres, Manuel

    2013-10-01

    To provide practical recommendations for evaluation and follow-up of patients with normocalcemic primary hyperparathyroidism. Members of the Bone Metabolism Working Group of the Spanish Society of Endocrinology. A systematic search was made in MEDLINE (PubMed), using the terms normocalcemic primary hyperparathyroidism and primary hyperparathyroidism, for articles in English published before 22 November 2012. Literature was reviewed by 2 members of the Bone Metabolism Working Group of the Spanish Society of Endocrinology, and after development of recommendations, the manuscript was reviewed by all other members of the Group, and their suggestions were incorporated. The document provides practical recommendations for evaluation and follow-up of patients with normocalcemic primary hyperparathyroidism. There is however little evidence available about different aspects of this disease, mainly progression rate and clinical impact. More data are therefore needed before definite recommendations may be made. Copyright © 2012 SEEN. Published by Elsevier Espana. All rights reserved.

  20. Pneumatic dilatation in achalasia cardia results and follow-up.

    Directory of Open Access Journals (Sweden)

    Supe A

    1990-10-01

    Full Text Available Pneumatic dilatation is one of the more recent methods in the management of achalasia cardia. Fifty dilatations were done in 42 patients with achalasia cardia over 5 years. There was a significant decrease in the maximum diameter of the oesophagus and a significant increase in diameter in the narrowed lower oesophageal segment in all the patients. Of the patients studied, 95.23% were relieved of their symptoms after only one to two sessions. There were no immediate complications. Out of the 38 patients on long term follow up, 8 (21.05% had recurrence of symptoms. On repeat dilatations, 4 (50% of them had good response. Late complication like reflux oesophagitis was observed in only 1 patient over a median follow up period of 22 months. It was thus concluded that pneumatic dilatation is a safe, simple and effective procedure in managing patients with achalasia cardia.

  1. Hyperfunctioning thyroid cancer: a five-year follow-up.

    Science.gov (United States)

    Azevedo, Monalisa Ferreira; Casulari, Luiz Augusto

    2010-02-01

    Differentiated thyroid cancer rarely occurs in association with hyperfunctioning nodules. We describe a case of a 47-year-old woman who developed symptoms of hyperthyroidism associated with a palpable thyroid nodule. Thyroid scintigraphy showed an autonomous nodule, and fine-needle aspiration biopsy was suggestive of papillary carcinoma. Laboratorial findings were consistent with the diagnosis of hyperthyroidism. The patient underwent thyroidectomy and a papillary carcinoma of 3.0 x 3.0 x 2.0 cm, follicular variant, was described by histological examination. The surrounding thyroid tissue was normal. Postoperatively, the patient received 100 mCi of (131)I, and whole body scans detected only residual uptake. No evidence of metastasis was detected during five years of follow-up. Hot thyroid nodules rarely harbor malignancies, and this case illustrated that, when a carcinoma occurs the prognosis seems to be very good with no evidence of metastatic dissemination during a long-term follow-up.

  2. Radiological follow-up of uncemented knee prostheses. Preliminary study

    International Nuclear Information System (INIS)

    Martin Hervas, C.; Gomez Barrena, E.; Marquez Moreno, I.; Calle Yuste, F.; Ordonez Parra, J.M.

    1993-01-01

    The preliminary results of a prospective study of 40 uncemented total knee prostheses (TKP) are presented following a radiological protocol with fluoroscopic control and follow-up of over 2 years. The prosthesis-bone interface and the components alignment were assessed. Several radiological signs were studied to assess this interface with respect to the fixing of the component, but they showed little clinical correlation. Statistical significance (p<0.05, chisquare) was found only in the observation of sclerosis in areas of support for the tibital tray as a reaction of the bone. This radiological follow-up is of interest to determine the evolution of the interface and position of the implant to prevent complications (especially loosening) in patients, particularly those under 60 years old, who represent the group that can most benefit from prosthetic systems with uncemented anchorage because of their life expectation and level of activity. Author

  3. Feasibility of an EIS Follow-up Program

    International Nuclear Information System (INIS)

    Nelson, I.C.; Jaquish, R.E.; Watson, D.G.

    1982-12-01

    The proposed level of an EIS Follow-up Program is believed to be feasible and that it can and should be implemented. Guidance to authors should result in fewer, but more important, commitments for mitigating adverse environmental impacts. Selecting the significant commitments from Records of Decisions published since July 1, 1979 for tracking to satisfaction should result in conformance with regulations, orders, and the intent of the NEPA

  4. Follow-up of prenatally diagnosed unilateral hydronephrosis

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens; Lenz, K; Rabol, A

    1996-01-01

    Based on previous experience with prenatally diagnosed unilateral hydronephrosis, we found that the primary indications for surgical intervention should be symptoms or functional impairment of the hydronephrotic kidney. Nonoperative management of neonates without symptoms and with normal function...... of the affected kidney was proposed. However, the strategy of treatment after prenatally diagnosed hydronephrosis is still controversial. We studied 28 consecutive children with suspected unilateral pelviureteral junction obstruction and a normal contralateral kidney. The overall follow-up period varied between 2...

  5. Ute Unit: Study Guide and Follow Up Activities.

    Science.gov (United States)

    North Conejos School District, Capulin, CO.

    The study guide and follow-up activities were designed primarily to give students a feeling of Ute life in the San Luis Valley in Colorado. The unit begins with six Southern Ute stories about the wolf and coyote, the race between the skunk and the coyote, the frog and the eagle, why the frog croaks, the bear (Que Ye Qat), and the two Indian…

  6. Radiographic follow-up study of Little Leaguer's shoulder

    International Nuclear Information System (INIS)

    Kanematsu, Yoshiji; Iwase, Takenobu; Matsuura, Tetsuya; Suzue, Naoto; Sairyo, Koichi; Kashiwaguchi, Shinji; Iwame, Toshiyuki

    2015-01-01

    Little Leaguer's shoulder is a syndrome involving the proximal humeral epiphyseal plate. Conservative treatment usually resolves the symptoms. However, there are no reports of a radiographic follow-up study of this disease. The purpose of this study was to show the radiographic healing process of Little Leaguer's shoulder. A total of 19 male baseball players diagnosed as having Little Leaguer's shoulder were retrospectively evaluated. The mean age at first presentation was 12.7 years. External rotation anteroposterior radiographs of the shoulder were taken. All patients were treated with rest from throwing, and no throwing was recommended until remodeling was confirmed. Follow-up radiographs were taken at 1-month intervals to assess healing. All patients were observed until healing was confirmed radiographically, after which they returned to baseball. The mean follow-up period was 8.5 months. In addition to radiography, patients were asked whether they had any symptoms and whether they had been able to return to baseball. At the first examination, radiographs showed a wider epiphyseal plate of the throwing side compared with the asymptomatic contralateral shoulder. Healing was observed in all cases. Healing occurred first along the medial side and was then extended laterally. The mean time required for healing was 4.7 months. All patients were able to return to playing baseball at their pre-injury level of play and were asymptomatic when examined at the final follow-up. The healing process of Little Leaguer's shoulder advanced from medial to lateral, and healing was achieved about 5 months after initial examination. (orig.)

  7. RATIR Follow-up of LIGO/Virgo Gravitational Wave Events

    Science.gov (United States)

    Golkhou, V. Zach; Butler, Nathaniel R.; Strausbaugh, Robert; Troja, Eleonora; Kutyrev, Alexander; Lee, William H.; Román-Zúñiga, Carlos G.; Watson, Alan M.

    2018-04-01

    We have recently witnessed the first multi-messenger detection of colliding neutron stars through gravitational waves (GWs) and electromagnetic (EM) waves (GW 170817) thanks to the joint efforts of LIGO/Virgo and Space/Ground-based telescopes. In this paper, we report on the RATIR follow-up observation strategies and show the results for the trigger G194575. This trigger is not of astrophysical interest; however, it is of great interest to the robust design of a follow-up engine to explore large sky-error regions. We discuss the development of an image-subtraction pipeline for the six-color, optical/NIR imaging camera RATIR. Considering a two-band (i and r) campaign in the fall of 2015, we find that the requirement of simultaneous detection in both bands leads to a factor ∼10 reduction in false alarm rate, which can be further reduced using additional bands. We also show that the performance of our proposed algorithm is robust to fluctuating observing conditions, maintaining a low false alarm rate with a modest decrease in system efficiency that can be overcome utilizing repeat visits. Expanding our pipeline to search for either optical or NIR detections (three or more bands), considering separately the optical riZ and NIR YJH bands, should result in a false alarm rate ≈1% and an efficiency ≈90%. RATIR’s simultaneous optical/NIR observations are expected to yield about one candidate transient in the vast 100 deg2 LIGO error region for prioritized follow-up with larger aperture telescopes.

  8. Follow-up of permanent hearing impairment in childhood.

    Science.gov (United States)

    Della Volpe, A; De Lucia, A; Pastore, V; Bracci Laudiero, L; Buonissimo, I; Ricci, G

    2016-02-01

    Programmes for early childhood childhood hearing impairment identification allows to quickly start the appropriate hearing aid fitting and rehabilitation process; nevertheless, a large number of patients do not join the treatment program. The goal of this article is to present the results of a strategic review of the strengths, weaknesses, opportunities and threats connected with the audiologic/prosthetic/language follow-up process of children with bilateral permanent hearing impairment. Involving small children, the follow-up includes the involvement of specialised professionals of a multidisciplinary team and a complex and prolonged multi-faced management. Within the framework of the Italian Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children", the purpose of this analysis was to propose recommendations that can harmonise criteria for outcome evaluation and provide guidance on the most appropriate assessment methods to be used in the follow-up course of children with permanent hearing impairment. © Copyright by Società Italiana di Otorinolaringologia e Chirurgia Cervico-Facciale.

  9. Neonatal follow-up program: Where do we stand?

    Science.gov (United States)

    2012-01-01

    Neonatal follow-up program (NFP) is becoming the corner stone of standard, high quality care provided to newborns at risk of future neuorodevelopmental delay. Most of the recognized neonatal intensive care units in the developed countries are adopting NFP as part of their mandatory care for the best long term outcome of high risk infants, especially very low birth weight (VLBW) infants. Unfortunately, in the developing and in underdeveloped countries, such early detection and intervention programs are rarely existing, mainly because of the lack of awareness of and exposure to such programs in spite of the increasing numbers of surviving sick newborns due to advancement in neonatal care in these countries. This is a review article to explore the Neonatal follow-up programs looking at historical development, benefts and aims, and standard requirements for successful program development that can be adopted in our countries. In conclusion, proper Neonatal follow-up programs are needed to improve neonatal outcome. Therefore all professionals working in the feld of neonatal care in developing countries should cooperate to create such programs for early detection and hence early intervention for any adverse long term outcome in high-risk newborn infants PMID:27493326

  10. Complications and Follow-up after Unprotected Carotid Artery Stenting

    International Nuclear Information System (INIS)

    Hauth, Elke A.M.; Drescher, Robert; Jansen, Christian; Gissler, H. Martin; Schwarz, Michael; Forsting, Michael; Jaeger, Horst J.; Mathias, Klaus D.

    2006-01-01

    Purpose. This prospective study was undertaken to determine the success rate, complications, and outcome of carotid artery stenting (CAS) without the use of cerebral protection devices. Methods. During 12 months, 94 high-grade stenoses of the carotid artery in 91 consecutive patients were treated. Sixty-six (70%) of the stenoses were symptomatic and 28 (30%) were asymptomatic. Results. In all 94 carotid stenoses CAS was successfully performed. During the procedure and within the 30 days afterwards, there were 2 deaths and 3 major strokes in the 66 symptomatic patients, resulting in a combined death and stroke rate of 5 of 66 (7%). Only one of these complications, a major stroke, occurred during the procedure. In the 6-month follow-up, one additional major stroke occurred in a originally symptomatic patient resulting in a combined death and stroke rate of 6 of 66 (10%) for symptomatic patients at 6 months. No major complications occurred in asymptomatic patients during the procedure or in the 6-month follow-up period. At 6 months angiographic follow-up the restenosis rate with a degree of >50% was 3 of 49 (6%) and the rate with a degree of ≥70% was 1 of 49 (2%). Conclusions. Cerebral embolization during CAS is not the only cause of the stroke and death rate associated with the procedure. The use of cerebral protection devices during the procedure may therefore not prevent all major complications following CAS

  11. Mortality in acromegaly: a 20-year follow-up study.

    Science.gov (United States)

    Ritvonen, Elina; Löyttyniemi, Eliisa; Jaatinen, Pia; Ebeling, Tapani; Moilanen, Leena; Nuutila, Pirjo; Kauppinen-Mäkelin, Ritva; Schalin-Jäntti, Camilla

    2016-06-01

    It is unclear whether mortality still is increased in acromegaly and whether there are gender-related differences. We dynamically assessed outcome during long-term follow-up in our nationwide cohort. We studied standardized mortality ratios (SMRs) relative to the general population and causes of death in acromegaly (n=333) compared with age- and gender-matched controls (n=4995). During 20 (0-33) years follow-up, 113 (34%) patients (n=333, 52% women) and 1334 (27%) controls (n=4995) died (P=0.004). SMR (1.9, 95% CI: 1.53-2.34, Pacromegaly. Overall distribution of causes of death (Pacromegaly, but not in controls, causes of deaths shifted from 44% cardiovascular and 28% cancer deaths during the first decade, to 23% cardiovascular and 35% cancer deaths during the next two decades. In acromegaly, cancer deaths were mostly attributed to pancreatic adenocarcinoma (n=5), breast (n=4), lung (n=3) and colon (n=3) carcinoma. In acromegaly, men were younger than women at diagnosis (median 44.5 vs 50 years, Pacromegaly, men are younger at diagnosis and death than women. Compared with controls, mortality is increased during 20 years of follow-up, especially in women. Causes of deaths shift from predominantly cardiovascular to cancer deaths. © 2016 Society for Endocrinology.

  12. [Guidelines for the follow up of patients with bronchopulmonary dysplasia].

    Science.gov (United States)

    Pérez Tarazona, S; Rueda Esteban, S; Alfonso Diego, J; Barrio Gómez de Agüero, M I; Callejón Callejón, A; Cortell Aznar, I; de la Serna Blázquez, O; Domingo Miró, X; García García, M L; García Hernández, G; Luna Paredes, C; Mesa Medina, O; Moreno Galdó, A; Moreno Requena, L; Pérez Pérez, G; Salcedo Posadas, A; Sánchez Solís de Querol, M; Torrent Vernetta, A; Valdesoiro Navarrete, L; Vilella Sabaté, M

    2016-01-01

    Bronchopulmonary dysplasia (BPD) is the most common complication of preterm birth, and remains a major problem in pediatric pulmonology units. The decision of discharging from the Neonatal Unit should be based on a thorough assessment of the condition of the patient and compliance with certain requirements, including respiratory and nutritional stability, and caregiver education on disease management. For proper control of the disease, a schedule of visits and complementary tests should be established prior to discharge, and guidelines for prevention of exacerbations and appropriate treatment should be applied. In this paper, the Working Group in Perinatal Respiratory Diseases of the Spanish Society of Pediatric Pulmonology proposes a protocol to serve as a reference for the follow up of patients with BPD among different centers and health care settings. Key factors to consider when planning discharge from the Neonatal Unit and during follow up are reviewed. Recommendations on treatment and prevention of complications are then discussed. The final section of this guide aims to provide a specific schedule for follow-up and diagnostic interventions to be performed in patients with BPD. Copyright © 2015 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  13. Follow-Up Photometry of Kelt Transiting Planet Candidates

    Science.gov (United States)

    Stephens, Denise C.; Joner, Michael D.; Hintz, Eric G.; Martin, Trevor; Spencer, Alex; Kelt Follow-Up Network (FUN) Team

    2017-10-01

    We have three telescopes at BYU that we use to follow-up possible transiting planet canidates for the KELT team. These telescopes were used to collect data on Kelt-16b and Kelt-9b, which is the hottest known exoplanet. More recently we used the newest of these telescopes, a robotic 8-inch telescope on the roof of our building, to confirm the most recent Kelt planet that will be published soon. This research has been ideal for the teaching and training of undergraduate students in the art of photometric observing and data reduction. In this presentation I will highlight how we are using our membership in the Kelt team to further the educational objective of our undergraduate astronomy program, while contributing meaningful science to the ever growing field of exoplanet discovery. I will also highlight a few of the more interesting Kelt planets and the minimum telescope requirements for detecting these planets. I will then discuss the sensitivities required to follow-up future TESS candidates, which may be of interest to others interested in joining the TESS follow-up teams.

  14. Appraising the value of independent EIA follow-up verifiers

    Energy Technology Data Exchange (ETDEWEB)

    Wessels, Jan-Albert, E-mail: janalbert.wessels@nwu.ac.za [School of Geo and Spatial Sciences, Department of Geography and Environmental Management, North-West University, C/O Hoffman and Borcherd Street, Potchefstroom, 2520 (South Africa); Retief, Francois, E-mail: francois.retief@nwu.ac.za [School of Geo and Spatial Sciences, Department of Geography and Environmental Management, North-West University, C/O Hoffman and Borcherd Street, Potchefstroom, 2520 (South Africa); Morrison-Saunders, Angus, E-mail: A.Morrison-Saunders@murdoch.edu.au [School of Geo and Spatial Sciences, Department of Geography and Environmental Management, North-West University, C/O Hoffman and Borcherd Street, Potchefstroom, 2520 (South Africa); Environmental Assessment, School of Environmental Science, Murdoch University, Australia. (Australia)

    2015-01-15

    Independent Environmental Impact Assessment (EIA) follow-up verifiers such as monitoring agencies, checkers, supervisors and control officers are active on various construction sites across the world. There are, however, differing views on the value that these verifiers add and very limited learning in EIA has been drawn from independent verifiers. This paper aims to appraise how and to what extent independent EIA follow-up verifiers add value in major construction projects in the developing country context of South Africa. A framework for appraising the role of independent verifiers was established and four South African case studies were examined through a mixture of site visits, project document analysis, and interviews. Appraisal results were documented in the performance areas of: planning, doing, checking, acting, public participating and integration with other programs. The results indicate that independent verifiers add most value to major construction projects when involved with screening EIA requirements of new projects, allocation of financial and human resources, checking legal compliance, influencing implementation, reporting conformance results, community and stakeholder engagement, integration with self-responsibility programs such as environmental management systems (EMS), and controlling records. It was apparent that verifiers could be more creatively utilized in pre-construction preparation, providing feedback of knowledge into assessment of new projects, giving input to the planning and design phase of projects, and performance evaluation. The study confirms the benefits of proponent and regulator follow-up, specifically in having independent verifiers that disclose information, facilitate discussion among stakeholders, are adaptable and proactive, aid in the integration of EIA with other programs, and instill trust in EIA enforcement by conformance evaluation. Overall, the study provides insight on how to harness the learning opportunities

  15. Appraising the value of independent EIA follow-up verifiers

    International Nuclear Information System (INIS)

    Wessels, Jan-Albert; Retief, Francois; Morrison-Saunders, Angus

    2015-01-01

    Independent Environmental Impact Assessment (EIA) follow-up verifiers such as monitoring agencies, checkers, supervisors and control officers are active on various construction sites across the world. There are, however, differing views on the value that these verifiers add and very limited learning in EIA has been drawn from independent verifiers. This paper aims to appraise how and to what extent independent EIA follow-up verifiers add value in major construction projects in the developing country context of South Africa. A framework for appraising the role of independent verifiers was established and four South African case studies were examined through a mixture of site visits, project document analysis, and interviews. Appraisal results were documented in the performance areas of: planning, doing, checking, acting, public participating and integration with other programs. The results indicate that independent verifiers add most value to major construction projects when involved with screening EIA requirements of new projects, allocation of financial and human resources, checking legal compliance, influencing implementation, reporting conformance results, community and stakeholder engagement, integration with self-responsibility programs such as environmental management systems (EMS), and controlling records. It was apparent that verifiers could be more creatively utilized in pre-construction preparation, providing feedback of knowledge into assessment of new projects, giving input to the planning and design phase of projects, and performance evaluation. The study confirms the benefits of proponent and regulator follow-up, specifically in having independent verifiers that disclose information, facilitate discussion among stakeholders, are adaptable and proactive, aid in the integration of EIA with other programs, and instill trust in EIA enforcement by conformance evaluation. Overall, the study provides insight on how to harness the learning opportunities

  16. X-ray image subtracting system

    International Nuclear Information System (INIS)

    Wesbey, W.H.; Keyes, G.S.; Georges, J.-P.J.

    1982-01-01

    An X-ray image subtracting system for making low contrast structures in the images more conspicuous is described. An X-ray source projects successive high and low energy X-ray beam pulses through a body and the resultant X-ray images are converted to optical images. Two image pick-up devices such as TV cameras that have synchronously operated shutters receive the alternate images and convert them to corresponding analog video signals. In some embodiments, the analog signals are converted to a matrix of digital pixel signals that are variously processed and subtracted and converted to signals for driving a TV monitor display and analog storage devices. In other embodiments the signals are processed and subtracted in analog form for display. The high and low energy pulses can follow each other immediately so good registration between subtracted images is obtainable even though the anatomy is in motion. The energy levels of the X-ray pulses are chosen to maximize the difference in attenuation between the anatomical structure which is to be subtracted out and that which remains. (author)

  17. Can JWST Follow Up on Gravitational-Wave Detections?

    Science.gov (United States)

    Kohler, Susanna

    2016-02-01

    Bitten by the gravitational-wave bug? While we await Thursdays press conference, heres some food for thought: if LIGO were able to detect gravitational waves from compact-object mergers, how could we follow up on the detections? A new study investigates whether the upcoming James Webb Space Telescope (JWST) will be able to observe electromagnetic signatures of some compact-object mergers.Hunting for MergersStudying compact-object mergers (mergers of black holes and neutron stars) can help us understand a wealth of subjects, like high-energy physics, how matter behaves at nuclear densities, how stars evolve, and how heavy elements in the universe were created.The Laser Interferometer Gravitational-Wave Observatory (LIGO) is searching for the signature ripples in spacetime identifying these mergers, but gravitational waves are squirrelly: LIGO will only be able to localize wave sources to tens of square degrees. If we want to find out more about any mergers LIGO discovers in gravitational waves, well need a follow-up search for electromagnetic counterparts with other observatories.The Kilonova KeyOne possible electromagnetic counterpart is kilonovae, explosions that can be produced during a merger of a binary neutron star or a neutron starblack hole system. If the neutron star is disrupted during the merger, some of the hot mass is flung outward and shines brightly by radioactive decay.Kilonovae are especially promising as electromagnetic counterparts to gravitational waves for three reasons:They emit isotropically, so the number of observable mergers isnt limited by relativistic beaming.They shine for a week, giving follow-up observatories time to search for them.The source location can beeasily recovered.The only problem? We dont currently have any sensitive survey instruments in the near-infrared band (where kilonova emission peaks) that can provide coverage over tens of square degrees. Luckily, we will soon have just the thing: JWST, launching in 2018!JWSTs

  18. Sleep During Menopausal Transition: A 6-Year Follow-Up.

    Science.gov (United States)

    Lampio, Laura; Polo-Kantola, Päivi; Himanen, Sari-Leena; Kurki, Samu; Huupponen, Eero; Engblom, Janne; Heinonen, Olli J; Polo, Olli; Saaresranta, Tarja

    2017-07-01

    Menopausal transition is associated with increased dissatisfaction with sleep, but the effects on sleep architecture are conflicting. This prospective 6-year follow-up study was designed to evaluate the changes in sleep stages and sleep continuity that occur in women during menopausal transition. Sixty women (mean age 46.0 years, SD 0.9) participated. All women were premenopausal at baseline, and at the 6-year follow-up, women were in different stages of menopausal transition. Polysomnography was used to study sleep architecture at baseline and follow-up. The effects of aging and menopause (assessed as change in serum follicle-stimulating hormone [S-FSH]) on sleep architecture were evaluated using linear regression models. After controlling for body mass index, vasomotor, and depressive symptoms, aging of 6 years resulted in shorter total sleep time (B -37.4, 95% confidence interval [CI] -71.5 to (-3.3)), lower sleep efficiency (B -6.5, 95%CI -12.7 to (-0.2)), as well as in increased transitions from slow-wave sleep (SWS) to wakefulness (B 1.0, 95%CI 0.1 to 1.9), wake after sleep onset (B 37.7, 95%CI 12.5 to 63.0), awakenings per hour (B 1.8, 95%CI 0.8 to 2.8), and arousal index (B 2.3, 95%CI 0.1 to 4.4). Higher S-FSH concentration in menopausal transition was associated with increased SWS (B 0.09, 95%CI 0.01 to 0.16) after controlling for confounding factors. A significant deterioration in sleep continuity occurs when women age from 46 to 52 years, but change from premenopausal to menopausal state restores some SWS. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  19. Neuroradiolological diagnosis and follow-up of brain tumors

    International Nuclear Information System (INIS)

    Kummer, R. von

    1997-01-01

    Primary tumors of the brain and cerebral metastases cause considerable morbidity and mortality. To assess the chance for cure and to develop a valid concept of treatment, the exact assessment of the tumor's location, of the tumor's borders and malignancy is essential. Today, neuroradiological examination mainly with magnetic resonance imaging (MRI) allows an almost histological diagnosis and description of the tumor's extent. MRI is as well useful for studying the patient's short- and long-term follow-up clinical course. This is illustrated by 3 case histories. (orig.)

  20. Primary cemented total hip arthroplasty: 10 years follow-up

    Directory of Open Access Journals (Sweden)

    Nath Rajendra

    2010-01-01

    Full Text Available Background: Primary cemented total hip arthroplasty is a procedure for non-traumatic and traumatic affections of the hip. Long term follow-up is required to assess the longevity of the implant and establish the procedure. Indo-Asian literature on long term result of total hip arthroplasty is sparse. We present a 10-year follow-up of our patients of primary cemented total hip arthroplasty. Materials and Methods: We operated 31 hips in 30 patients with primary cemented total hip arthroplasty. We followed the cases for a minimum period of 10 years with a mean follow-up period of 12.7 years. The mean age of the patients was 60.7 years (range 37-82 yrs male to female ratio was 2:1. The clinical diagnoses included - avascular necrosis of femoral head (n=15, sero positive rheumatoid arthritis (n=5, seronegative spondylo-arthropathy (n=4, neglected femoral neck fractures (n=3, healed tubercular arthritis (n=2 and post traumatic osteoarthritis of hip (n=2. The prostheses used were cemented Charnley′s total hip (n=12 and cemented modular prosthesis (n=19. The results were assessed according to Harris hip score and radiographs taken at yearly intervals. Results: The mean follow-up is 12.7 yrs (range 11-16 yrs Results in all operated patients showed marked improvement in Harris hip score from preoperative mean 29.2 to 79.9 at 10 years or more followup. However, the non-inflammatory group showed more sustained long term improvement as compared to the inflammatory group, as revealed by the Harris hip score. Mean blood loss was 450ml (±3.7 ml, mean transfusion rate was 1.2 units (±.3. The complications were hypotension (n=7, shortening> 1.5 cm (n=9, superficial infection (n=2 and malposition of prosthesis (n=1. Conclusion: The needs of Indian Asian patients, vary from what is discussed in literature. The pain tolerance is greater than western population and financial constraints are high. Thus revision surgery among Indian-Asian patients is less compared

  1. GRBs optical follow-up observation at Lunin observatory, Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Huang, K.Y.; Ip, W.H. [Chung-Li Univ., Taiwan (China). Institute of astronomy; Urata, Y. [RIKEN, Saitama (Japan); Tokyo Institute of Technology, Tokyo (Japan). Department of Physics; Tamagawa, T.; Onda, K. [RIKEN, Saitama (Japan); Makishima, K. [RIKEN, Saitama (Japan); Tokyo Univ., Tokyo (Japan). Department of Physics

    2005-07-15

    The Lulin GRB program, using the Lulin One-meter Telescope (LOT) in Taiwan started in July 2003. Its scientific aims are to discover optical counterparts of XRFs and short and long GRBs, then to quickly observe them in multiple bands. Thirteen follow-up observations were provided by LOT between July 2003 and Feb. 2005. One host galaxy was found at GRB 031203. Two optical afterglows were detected for GRB 040924 and GRB 041006. In addition, the optical observations of GRB 031203 and a discussion of the non-detection of the optical afterglow of GRB 031203 are also reported in this article.

  2. GRBs optical follow-up observation at Lunin observatory, Taiwan

    International Nuclear Information System (INIS)

    Huang, K.Y.; Ip, W.H.; Makishima, K.; Tokyo Univ., Tokyo

    2005-01-01

    The Lulin GRB program, using the Lulin One-meter Telescope (LOT) in Taiwan started in July 2003. Its scientific aims are to discover optical counterparts of XRFs and short and long GRBs, then to quickly observe them in multiple bands. Thirteen follow-up observations were provided by LOT between July 2003 and Feb. 2005. One host galaxy was found at GRB 031203. Two optical afterglows were detected for GRB 040924 and GRB 041006. In addition, the optical observations of GRB 031203 and a discussion of the non-detection of the optical afterglow of GRB 031203 are also reported in this article

  3. Postoperative follow-up studies in biliary atresia using radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Kanto, Kei; Ishida, Haruo; Hayashi, Akira; Kamagata, Shoichiro; Sanbonmatsu, Toru; Matsufuji, Hiroshi; Ishii, Katsumi

    1988-09-01

    With increasing numbers of long survival patients in biliary atresia, associated diseases such as liver cirrhosis and portal hypertension seem to be more important in their course. We use liver scintigraphy, hepatobiliary scintigraphy and transrectal portal scintigraphy as the follow-up study. Three studies generally correlate the present state of the patients, but there seems to be dissociation in the group of cirrhosis without icterus which are encountered most often in biliary atresia. That can be seen in hepatobiliary scintigraphy especially. So we emphasis that to choose several isotope studies are essential in determination of the postoperative state in biliary atresia.

  4. Follow-up study of memory deficits after ECT.

    Science.gov (United States)

    Shellenberger, W; Miller, M J; Small, I F; Milstein, V; Stout, J R

    1982-06-01

    Twenty-four patients received ECT induced by either alternating sine wave or brief pulsed-square wave stimulus and were evaluated at follow-up for clinical functioning and subjective memory loss. The hypothesis of less memory loss in the group receiving a weaker stimulus (pulsed-square wave) was not supported. The two treatment groups and a group of controls showed no significant differences on the memory test. On measures of clinical functioning the sine wave group scored better on every measure than the square wave group, although not significantly better.

  5. A follow-up of transients. Stage 1

    International Nuclear Information System (INIS)

    Enekull, Aa.; Wallner, B.

    1981-09-01

    A follow-up of the transients of temperature and pressure in the primary pressurized system of a nuclear power plant has been completed for the Barsebaeck-1 reactor. The investigation consists of the following steps:- the collation of transients - drawing up load data based on transients-analyses of stress - recommendations for future programs. It was found that the lifetime of the system will exceed 40 years excluding some of the pipes for feed water. The appendices give a detailed description of the transients.(G.B.)

  6. Shillapoo Wildlife Area 2007 Follow-up HEP Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul R.

    2008-03-01

    In April and May 2007 the Regional HEP Team (RHT) conducted a follow-up HEP analysis on the Egger (612 acres) and Herzog (210 acres) parcels located at the north end of the Shillapoo Wildlife Area. The Egger and Herzog parcels have been managed with Bonneville Power Administration funds since acquired in 1998 and 2001 respectively. Slightly more than 936 habitat units (936.47) or 1.14 HUs per acre was generated as an outcome of the 2007 follow-up HEP surveys. Results included 1.65 black-capped chickadee HUs, 280.57 great blue heron HUs, 581.45 Canada goose HUs, 40 mallard HUs, and 32.80 mink HUs. Introduction A follow-up Habitat Evaluation Procedures (HEP) (USFWS 1980) analysis was conducted by the Columbia Basin Fish and Wildlife Authority's (CBFWA) Regional HEP Team (RHT) during April and May 2007 to document changes in habitat quality and to determine the number of habitat units (HUs) to credit Bonneville Power Administration (BPA) for providing operation and maintenance (O&M) funds since WDFW acquired the parcels. The 2007 follow-up HEP evaluation was limited to Shillapoo Wildlife Area (SWA) parcels purchased with Bonneville Power Administration funds. D. Budd (pers. comm.) reported WDFW purchased the 612 acre Egger Farms parcel on November 2, 1998 for $1,737,0001 and the 210 acre Herzog acquisition on June 21, 2001 for $500,000 with Memorandum of Agreement funds (BPA and WDFW 1996) as partial fulfillment of BPA's wildlife mitigation obligation for construction of Bonneville and John Day Dams (Rasmussen and Wright 1989). Anticipating the eventual acquisition of the Egger and Herzog properties, WDFW conducted HEP surveys on these lands in 1994 to determine the potential number of habitat units to be credited to BPA. As a result, HEP surveys and habitat unit calculations were completed as much as seven years prior to acquiring the sites. The term 'Shillapoo Wildlife Area' will be used to describe only the Herzog and Egger parcels in this

  7. Follow-up of young road accident victims.

    Science.gov (United States)

    Gillies, Marjorie L; Barton, Joanne; Di Gallo, Alain

    2003-10-01

    The aim of this study was to follow-up a group of children and young people previously examined for psychological sequelae following road traffic accidents. The group was assessed 18-month postaccident to assess the severity of continuing symptoms and examine any emergence of delayed onset of posttraumatic stress reactions. Participants (N = 31) completed the Revised Impact of Event Scale and the Child Posttraumatic Stress Reaction Index. Parents completed the Child Behavior Check-List and participated in a semistructured interview. Symptoms of PTSD were noted in a quarter of participants as was delayed onset of symptoms. The role of avoidance in symptom reporting and continuing disorder is discussed.

  8. Automated medical follow-up and delayed industrial risks

    International Nuclear Information System (INIS)

    Smith, M.E.

    In response to increasing demand for human data to identify social, environmental, and occupational influences upon health, Statistics Canada has been organizing existing files of vital and health records to facilitate such studies on a national scale. In particular, the development of a Canadian Mortality Data Base file, the initiation of the National Cancer Incidence system, and the development of new computer techniques have helped reduce the cost and increase the scale and efficiency of automated medical follow-up to produce statistics of sickness or death attributable to environmental factors. Specific occupational studies now in progress serve to illustrate the methods, practical difficulties, potential size, and products from such investigations

  9. Destructive spondyloarthropathy and radiographic follow-up in hemodialysis patients

    International Nuclear Information System (INIS)

    Orzincolo, C.; Cardona, P.; Bedani, P.L.; Gilli, P.; Scutellari, P.N.; Trotta, F.

    1990-01-01

    Nine patients undergoing regular dialytic treatment for more than 60 months showed clinical and radiologic features of a noninfective and destructive spondyloarthropathy. Typically, radiographs and CT scans revealed narrowing of intervertebral spaces, with destruction or sclerosis of the subchondral bone of the vertebral plate. A radiographic follow-up of the cervical spine was performed in seven patients after a period of 12 months and showed that the bone destruction in DSA is very rapid and progressive. The lower biocompatibility of the cuprophan membranes of dialyzers is probably the factor most responsible for hyperproduction of β 2 -m and subsequently osteoarticular deposition of a new type of amyloidosis. (orig./DG)

  10. Simplified method evaluation for piping elastic follow-up

    International Nuclear Information System (INIS)

    Severud, L.K.

    1983-05-01

    A proposed simplified method for evaluating elastic follow-up effects in high temperature pipelines is presented. The method was evaluated by comparing the simplified analysis results with those obtained from detailed inelastic solutions. Nine different pipelines typical of a nuclear breeder reactor power plant were analyzed; the simplified method is attractive because it appears to give fairly accurate and conservative results. It is easy to apply and inexpensive since it employs iterative elastic solutions for the pipeline coupled with the readily available isochronous stress-strain data provided in the ASME Code

  11. Follow up study of Alzheimer's type dementia with computed tomography

    International Nuclear Information System (INIS)

    Hirata, Nobuhide

    1987-01-01

    In 54 patients who were diagnosed as having Alzheimer's type dementia based on the Diagnostic and Statistical Manual of Mental Disorders, III, cranial computed tomography (CT) scans were obtained before and after their follow-up study ranging from 6 to 24 months (mean 15.4 +- 4.7 months). Cerebrospinal percentage and CT density in various regions of interest were examined. Six patients died during the study. Comparison of the group of the deceased (Group I) with the group of survivors (Group II) revealed: (1) there was no difference in average age and the degree of mental disorder at first presentation; (2) Group I had decreased activities of daily living; and (3) CT density was significantly decreased in the bilateral lateral and frontal lobes in Group I. As for Group II, decreased CT numbers were noticeable during the follow-up period in the frontal lobe, parietal lobe, and caudate nucleus in the group evaluated as aggravated, as compared with the group evaluated as unchanged. (Namekawa, K.)

  12. Rothmund-Thomson Syndrome: A 13-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Guillermo Antonio Guerrero-González

    2014-07-01

    Full Text Available Rothmund-Thomson syndrome (RTS is a rare autosomal recessive disorder presenting with poikiloderma and other clinical features, affecting the bones and eyes and, in type II RTS, presenting an increased risk for malignancy. With about 300 cases reported so far, we present a 13-year follow-up including clinical images, X-rays and genetic analysis. A 13-month-old female started with a facial rash with blisters on her cheeks and limbs at the age of 3 months along with congenital hypoplastic thumbs, frontal bossing and fine hair, eyebrows and eyelashes. The patient was lost to follow-up and returned 12 years later with palmoplantar hyperkeratotic lesions, short stature, disseminated poikiloderma and sparse scalp hair, with absence of eyelashes and eyebrows. Radiographic analysis showed radial ray defect, absence of the thumb and three wrist carpal bones, and reduced bone density. Gene sequencing for the RECQL4 helicase gene revealed a mutation on each allele. RTS is a rare disease, and in this patient we observed the evolution of her skin lesions and other clinical features, which were important for the classification of type II RTS. The next years will provide even more information on this rare disease.

  13. [Follow-up of children conceived by assisted reproductive technologies].

    Science.gov (United States)

    Bouillon, C; Fauque, P

    2013-05-01

    Since the birth of the first baby conceived by in vitro fertilization (IVF) 30 years ago (Louise Brown in 1978), there has been a rapid and constant increase in the number of couples using assisted reproductive technologies (ART). Around four million of children have been born from couples experiencing fertility problems, through the use of ART, comprising roughly 2-3 % of all births in Europe and U.S. That highlights that these modes of fertilization are now well assumed by our societies. However, several questions on health of these children remain to be elucidated. As evoked in this review, even if methodological limitations exist, numerous studies have reported increased risks of birth defects, like prematurity, foetal hypotrophy, neonatal complications, congenital malformations and epigenetic diseases among ART-conceived children as compared to naturally conceived children. Nowadays, it is difficult to determine if these increased risks found in ART infants are a consequence of the ART procedures or are inherent to the infertility problems per se. However, absolute risks remain moderate and reassuring as well as the data on follow-up into infancy and early childhood. Nevertheless, because the effects may occur at the adulthood, there is a need for long-term follow-up of children born after ART. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  14. Follow-up of pulmonary perfusion recovery after embolism

    International Nuclear Information System (INIS)

    Palla, A.; Donnamaria, V.; Petruzzelli, S.; Giuntini, C.

    1986-01-01

    Blood flow recovery in a group of 69 patients with pulmonary embolism was followed by serial lung scans over a six month period. Each patient underwent perfusion lung scan at diagnosis then 7, 30 and 180 days later; i.v. heparin was systematically administered for one week after diagnosis, followed by oral warfarin for six months. Blood flow impairment was evaluated by assessing the total number of unperfused lung segments (ULS), as calculated on both lateral views at each scan. The number of ULS was significantly reduced at each interval (P<0.001), ranging from 8.4±3.3 at diagnosis to 3.6±2.7 six months later; most of the recovery (79%) occurred within the first month. No patient had complete restoration of pulmonary blood flow during the whole follow-up period. No difference was found between the number of ULS in right lung versus that in left lung at each interval. Recovery of blood flow was heavily affected by coexisting cardiac or pulmonary disease. In fact, those patients with underlying cardiopulmonary disease (49.2% of the total) showed significantly smaller perfusion improvement after six months (P<0.001). Eight patients (6 with and 2 without cardiopulmonary disease) had clinical and scintigraphic evidence of recurrent embolism during the follow-up period

  15. Gastric and Duodenal Stents: Follow-Up and Complications

    International Nuclear Information System (INIS)

    Pinto Pabon, Isabel Teresa; Paul Diaz, Laura; Ruiz de Adana, Juan Carlos; Lopez Herrero, Julio

    2001-01-01

    Purpose: To assess the efficacy of self-expanding metallic stents in treating inoperable gastric and duodenal stenoses during follow-up and to evaluate the complications encountered.Methods: A total of 31 patients suffering from gastroduodenal obstruction (29 malignant, 2 benign) were treated with a self-expanding metallic stent (Wallstent). In 24 cases insertion was by the peroral route, in seven cases via gastrostomy.Results: All the strictures were successfully negotiated under fluoroscopic guidance without having to resort to endoscopy. A total of 27 patients (87%) were able to resume a regular diet, a soft diet, or a liquid diet orally. Complications included one case of stent malpositioning, one case of leakage of ascitic fluid through the gastrostomy orifice, one case of perforation and fistula to the biliary tree, and two cases of hematemesis. In two patients (6%) additional stents were implanted to improve patency. In all patients follow-up was maintained until death. Recurrence of symptoms immediately before death occurred in seven cases (23%). Mean survival time of patients was 13.3 weeks (SE ± 4.6).Conclusions: The deployment of gastroduodenal stents resulted in good palliation of inoperable gastric and duodenal stenoses. Certain technical aspects, e.g., adaptation of stents to bowel morphology, is critical to proper stent function and avoidance of complications

  16. CT follow-up after radiation therapy for pituitary adenomas

    International Nuclear Information System (INIS)

    Rush, S.C.; Newall, J.

    1988-01-01

    Between 1973 and 1985, 105 patients received radiation therapy as all or part of their treatment for pituitary tumor at the New York University Medical Center. Of these, 48 patients underwent computed tomography (CT) at a minimum of 2 years following treatment, with detailed reports available for analysis of tumor regression. There were 28 men with a median age of 46 years (range, 18-71 years) and 20 women with a median age of 53 years (range, 28-80 years). Tumors were classified as secretory in 23 patients, nonsecretory in 21, and undetermined in four. Sixteen patients were treated with radiation therapy alone, 23 patients with surgery and radiation therapy, and the other with bromocriptine and radiation therapy, with or without surgery. With a median follow-up of 5 years (range, 2-14 years), 16 patients developed an empty sella, 25 patients had residual sellar mass, and seven patients had persistent extrasellar components or no change in their intrasellar mass. Among patients who did not have hypopituitarism at the inception of radiation therapy, five of 13 with empty sellas and 12 of 22 with residual mass subsequently required therapy. The authors conclude that residual mass is commonly found in long-term follow-up after radiation therapy, that isolated imaging studies revealing such findings after treatment in no way herald a diagnosis of recurrence, and that hypopituitarism following pituitary radiation therapy does not correlate with the ablation or persistence of tissue within the sella

  17. Follow-up of breast cancer by bone scintigraphy

    International Nuclear Information System (INIS)

    Garcia N, E.; Castro, F.; Miranda, R.; Leon, L.; Bustamante, G.; Escobar, M.

    2004-01-01

    Full text: Breast cancer is one of the most common cancers in women. It is the second most widespread cancer in Mexican women. Among the several methods for diagnosis and follow up of the disease, tumor markers like CA-53 have high sensitivity and specificity. Bone scan is a useful method in the detection of bone metastases. In comparison to other diagnostic modalities, bone scan is more sensitive and less expensive for detection of early bone abnormalities and hence to select an appropriate treatment for better prognosis. In our country, in about 70% of cases diagnosis of breast cancer is made when the disease is in an advanced state - states III and IV. The aim of this study was to evaluate the follow up of breast cancer by bone scans and to correlate these findings with the stage of the disease and other diagnostic modalities. The work was carried out at Mexican General Hospital. A total of 350 patients with breast tumor were included; bone scans were performed in all patients at the time of clinical diagnosis and at every 6 months for a period of 1 to 5 years using an Elscint APEX SP6 HR gamma camera coupled with ultra high resolution collimator. Scan was performed 2-3 hours after intravenous administration of 555-925 MBq of Tc-99m methyl diphosphonate. Tumor classification was made according to TNM criteria. Serum levels of alkaline phosphates, carcino-embrionic antigen (CEA) and Ca 53 were also measured on the same day. Fifty-one patients confirmed to have a diagnosis of benign breast were excluded from the study group. Of the remaining 299 patients, 89 (39%) were between 41 years to 50 years, 69 between 51 to 60 years. The clinical stage most commonly observed was stage III (n=164, 54%) followed by stage II (25%). In 59.5% of patients, scintigraphy showed bone metastasis. Four patients with bone metastases showed regression and 42 (14%) with negative scans became positive on follow up bone scans. Ninety-three patients were free of bone metastases during all

  18. Long term follow up of medical therapy of thyroid cancer

    International Nuclear Information System (INIS)

    Jaffiol, C.; Daures, J.P.; Nsakala, N.; Guerenova, J.; Baldet, L.; Pujol, P.; Vannereau, D.; Bringer, J.

    1995-01-01

    106 patients, 114 W, 27 M, were thyroidectomized for differentiated thyroid cancer (follicular 29.3% - papillary 54.3%) with different stages of gravity (N O: 48.2% - N 1: 32.8% - N 2: 19%). Neck dissection was used in cases of involved nodes. One or several doses of 131 I were given to 126 subjects, 106 patients were treated with L thyroxine (LT4) (mean daily dose: 2.5 μg/kg BW). 23 patients presenting intolerance to LT4 with non suppressed TSH for 13 of them were treated by an association of tiratricol (TRIAC) + LT4. The follow up included a yearly check up involving clinical examination, plasma thyroglobulin (Tg) and thyroid stimulating hormone (TSH) assessment, neck ultrasonography and X ray of the chest. Therapy was stopped for 4 weeks in cases with Tg above its detectable value and a total body scan performed with Tg and TSH controls. The mean duration of follow up was 94.5 ± 67.7 months and extended to more than 5 years for 61% of the patients. We observed 22 relapses of the tumor with 4 deaths. Age less then 45 years, appears as the best factor of prognosis. 2 groups of patients were compared to evaluate the incidence of TSH suppression on the relapse free survival (group 1 n = 30 with a TSH ≤ 0.10 mU/1 and group 2 n = 15 with a TSH always > 1 mU/1 during the follow up). The relapse free survival was shorter in group 2 (p 0.01). Association of TRIAC with LT4 leads to a reduction of the daily dose of LT4 (m 25μg/day) with a significant improvement of TSH suppression and clinical tolerance. In conclusion, TSH suppression improves the prognosis in thyroidectomized patients for differentiated carcinoma. Association of TRIAC with LT4 seems able to approve TSH suppression and therapeutic tolerance. (authors). 40 refs., 5 tabs

  19. Vaginismus Treatment: Clinical Trials Follow Up 241 Patients.

    Science.gov (United States)

    Pacik, Peter T; Geletta, Simon

    2017-06-01

    Vaginismus is mostly unknown among clinicians and women. Vaginismus causes women to have fear, anxiety, and pain with penetration attempts. To present a large cohort of patients based on prior published studies approved by an institutional review board and the Food and Drug Administration using a comprehensive multimodal vaginismus treatment program to treat the physical and psychologic manifestations of women with vaginismus and to record successes, failures, and untoward effects of this treatment approach. Assessment of vaginismus included a comprehensive pretreatment questionnaire, the Female Sexual Function Index (FSFI), and consultation. All patients signed a detailed informed consent. Treatment consisted of a multimodal approach including intravaginal injections of onabotulinumtoxinA (Botox) and bupivacaine, progressive dilation under conscious sedation, indwelling dilator, follow-up and support with office visits, phone calls, e-mails, dilation logs, and FSFI reports. Logs noting dilation progression, pain and anxiety scores, time to achieve intercourse, setbacks, and untoward effects. Post-treatment FSFI scores were compared with preprocedure scores. One hundred seventy-one patients (71%) reported having pain-free intercourse at a mean of 5.1 weeks (median = 2.5). Six patients (2.5%) were unable to achieve intercourse within a 1-year period after treatment and 64 patients (26.6%) were lost to follow-up. The change in the overall FSFI score measured at baseline, 3 months, 6 months, and 1 year was statistically significant at the 0.05 level. Three patients developed mild temporary stress incontinence, two patients developed a short period of temporary blurred vision, and one patient developed temporary excessive vaginal dryness. All adverse events resolved by approximately 4 months. One patient required retreatment followed by successful coitus. A multimodal program that treated the physical and psychologic aspects of vaginismus enabled women to achieve

  20. Mammographic follow-up after conservation therapy for breast cancer

    International Nuclear Information System (INIS)

    Gu Yajia; Xiao Qin; Zheng Xiaojing; Wu Jiong; Chen Jiayi; Gu Rongfeng; Feng Xiaoyuan

    2006-01-01

    Objective: To recognize the mammographic changes after conservation therapy for breast carcinoma. Methods: A total of 139 follow-up mammographic examinations in 85 cases were studied during the period between 1999 and 2004. Mammography was performed at intervals of 6 months for the first 2 years, then annually. Attention was paid to mammographic change patterns of conservation therapy for breast carcinoma, including breast edema, skin thickening, architectural disturbance, asymmetric density, architectural distortion retraction, and calcifications. SPSS version 11.0 for windows was used to perform all statistical tests. Kruskal-Wallis H test was used for calculating the overall statistical differences between difference periods. Categorical data were expressed as percentages and analyzed by using the X 2 test. The age of the patients ranged from 25 to 63 years (mediate, 44 years old). The time of follow-up observation ranged from 1 week to 72 months. Results: Two cases were normal on mammograms. High proportion of abnormal mammography was seen in the period of 12 month (40.3%, 56/139) and 24 month (21.6%, 30/139), respectively. Various findings appeared in various periods and the difference was statistically significant(X 2 =30.998, v=6, P=0.001). Mild edema appeared in the first 3 years. Moderately severe or marked breast edema may be present between 6 months to 12 months, then slowly resolved. The appearance and disappearance of skin thickening were similar to the process of breast edema. The changes of architectural disturbance did not correlate with time (X 2 =8.634, P>0.05), but on sequential mammograms for same patient, the extent of architectural disturbance relieved over time (17/19). Asymmetric density was found in only 5 patients, and disappeared in later period of follow-up in 3. Architectural distortion retraction got more and more obvious with time, and kept stable after certain period of time. Calcifications were shown in 2 patients, including 1

  1. Role of imaging in glaucoma diagnosis and follow-up

    Directory of Open Access Journals (Sweden)

    Vizzeri Gianmarco

    2011-12-01

    Full Text Available The purpose of the review is to provide an update on the role of imaging devices in the diagnosis and follow-up of glaucoma with an emphasis on techniques for detecting glaucomatous progression and the newer spectral domain optical coherence tomography instruments. Imaging instruments provide objective quantitative measures of the optic disc and the retinal nerve fiber layer and are increasingly utilized in clinical practice. This review will summarize the recent enhancements in confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography with an emphasis on how to utilize these techniques to manage glaucoma patients and highlight the strengths and limitations of each technology. In addition, this review will briefly describe the sophisticated data analysis strategies that are now available to detect glaucomatous change overtime.

  2. Patients’ Vulnerability in Follow-up After Colorectal Cancer

    DEFF Research Database (Denmark)

    Thomsen, Thora Grothe; Hølge-Hazelton, Bibi

    2017-01-01

    and reorganizing follow-up after cancer treatment. OBJECTIVE:: The aim of this study was to identify the perspectives of fast-track colorectal cancer surgery patients on challenges experienced in the transition from being a hospitalized patient with cancer to being a cancer survivor. METHODS:: The current article......BACKGROUND:: In the transition between being a hospitalized patient with cancer and resuming “normal” life, many patients experience physical, mental, and social challenges. Scientifically, as well as politically, it is therefore recommended to undertake research with a focus on rethinking...... hospital after a few days; however, shortly after returning home, most of them became mentally overwhelmed by the feeling of vulnerability that was closely related to the feeling of being handed over the responsibility for a newly cancer-operated body and a fragile life situation. Four issues...

  3. Scintigraphic follow-up of fracture healing in animals

    International Nuclear Information System (INIS)

    Klug, W.; Franke, W.G.; Schulze, M.

    1983-01-01

    Secondary bone fracture heating was analysed by scintigraphic follow-up studies in rabbits using sup(99m)Tc-HEDP. 24 hours after fracture the activity ratio between the fractured and the non-fractured lower limb was 2,2. The maximal count density in the fracture region is found during the 14th and 28th day after fracture. Concomitantly there is a significant increase of bone marrow vessels and content of copper, magnesium, sodium and water in the callus. Although roentgenographic controls and static investigations with respect to consolidation reveal a complete heating already 126 days after fracture, the complete scintigraphic normalisation of the lower limb fracture of the rabbit is found not earlier than at the 203rd day after fracture. (orig.) [de

  4. Scintigraphic follow-up of fracture healing in animals

    Energy Technology Data Exchange (ETDEWEB)

    Klug, W.; Franke, W.G.; Schulze, M.

    1983-08-01

    Secondary bone fracture healing was analysed by scintigraphic follow-up studies in rabbits using sup(99m)Tc-HEDP. 24 hours after fracture the activity ratio between the fractured and the non-fractured lower limb was 2,2. The maximal count density in the fracture region is found during the 14th and 28th day after fracture. Concomitantly there is a significant increase of bone marrow vessels and content of copper, magnesium, sodium and water in the callus. Although roentgenographic controls and static investigations with respect to consolidation reveal a complete healing already 126 days after fracture, the complete scintigraphic normalisation of the lower limb fracture of the rabbit is found not earlier than at the 203rd day after fracture.

  5. Epidemiological follow-up study of Japanese Thorotrast cases

    International Nuclear Information System (INIS)

    Mori, T.; Maruyama, T.; Kato, Y.; Takahashi, S.

    1979-01-01

    The authors conducted a follow-up study on 243 Thorotrast-administered war-wounded ex-servicemen in 1975, after a lapse of 30 to 38 years from Thorotrast injections, and found 18 cases of malignant hepatic tumor, 15 cases of other malignant tumors, 2 cases of blood diseases, and 9 cases of liver cirrhosis in 224 cases who had been given Thorotrast intravascularly. The incidence of hepatic and other malignant tumors, blood diseases, and liver cirrhosis was significantly higher than in the controls. The total number of deaths in the Thorotrast-administered cases was also significantly higher than in the controls. In the remaining 19 cases who had been given Thorotrast by a route other than intravascularly, no fatal case related to Thorotrast administration was discovered. In the living cases, however, one sarcoma was observed to have developed at the site of the Thorotrast injection

  6. [Neuromuscular disease: respiratory clinical assessment and follow-up].

    Science.gov (United States)

    Martínez Carrasco, C; Villa Asensi, J R; Luna Paredes, M C; Osona Rodríguez de Torres, F B; Peña Zarza, J A; Larramona Carrera, H; Costa Colomer, J

    2014-10-01

    Patients with neuromuscular disease are an important group at risk of frequently suffering acute or chronic respiratory failure, which is their main cause of death. They require follow-up by a pediatric respiratory medicine specialist from birth or diagnosis in order to confirm the diagnosis and treat any respiratory complications within a multidisciplinary context. The ventilatory support and the cough assistance have improved the quality of life and long-term survival for many of these patients. In this paper, the authors review the pathophysiology, respiratory function evaluation, sleep disorders, and the most frequent respiratory complications in neuromuscular diseases. The various treatments used, from a respiratory medicine point of view, will be analyzed in a next paper. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  7. A follow-up of 72 cases referred for abortion.

    Science.gov (United States)

    Gillis, A

    1975-01-01

    Whilst the medical indications for therapeutic abortion and the legal limitations set vary enormously from one country to another there is in general an undoubted trend towards giving the pregnant woman herself a greater say in the decision. During the first year of the operation of the Abortion Act, 1967, in England some 72 pregnant women were referred to the author and his colleagues for a recommendation on abortion. A psychiatric examination and follow-up over a period of one year was made both in those cases where abortion was performed as well as in those cases who were refused therapeutic abortion. In this communication a comparison is made between the reactions and outcome in the two groups. A provisional conclusion is reached that no significant psychiatric disturbance could be attributed to the performance of the operation or on the other hand to refusal of the woman's request.

  8. Vertebral sarcoidosis: long-term follow-up with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lefere, M. [University Hospitals Gasthuisberg, Department of Radiology, Leuven (Belgium); Larbi, A.; Malghem, J.; Vande Berg, B.; Dallaudiere, B. [University Hospitals St Luc, Department of Radiology, Brussels (Belgium)

    2014-08-15

    Vertebral involvement in sarcoidosis is rare and its clinical and imaging features are non-specific. Indeed, because the lesions are hard to differentiate from metastatic disease based on imaging alone, a histological confirmation is advised. Fatty replacement is a well-known finding indicating stabilization and healing in both benign and malignant conditions. It can be used as an indicator of a favorable disease course and response to treatment. We report the case of a 43-year-old woman with multifocal vertebral sarcoidosis lesions and long-term follow-up showing progressive and gradual fatty involution on magnetic resonance imaging (MRI) during 4 years of steroid treatment with a final favorable outcome. (orig.)

  9. Hydrotherapy after total knee arthroplasty. A follow-up study.

    Science.gov (United States)

    Giaquinto, S; Ciotola, E; Dall'Armi, V; Margutti, F

    2010-01-01

    The study evaluated the subjective functional outcome following total knee arthroplasty (TKA) in participants who underwent hydrotherapy (HT) six months after discharge from a rehabilitation unit. A total of 70 subjects, 12 of which were lost at follow-up, were randomly assigned to either a conventional gym treatment (N=30) or HT (N=28). A prospective design was performed. Participants were interviewed with Western-Ontario McMasters Universities Osteoarthritis Index (WOMAC) at admission, at discharge and six months later. Kruskal-Wallis and Wilcoxon tests were applied for statistical analysis. Both groups improved. The WOMAC subscales, namely pain, stiffness and function, were all positively affected. Statistical analysis indicates that scores on all subscales were significantly lower for the HT group. The benefits gained by the time of discharge were still found after six months. HT is recommended after TKA in a geriatric population. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  10. Contrast-enhanced three-dimensional fast-spoiled gradient magnetic resonance angiography of the renal arteries for potential living renal transplant donors: a comparative study with digital subtraction angiography

    International Nuclear Information System (INIS)

    Al-Saeed, O.; Sheikh, M.; Al-Khawari, H.; Ismail, M.; Al-Moosawi, M.

    2005-01-01

    Preoperative assessment of the arterial anatomy of prospective renal donors is essential. Various non-invasive techniques are used for such evaluation. We conducted this study using contrast-enhanced 3-D fast-spoiled gradient (CE 3-D FSPGR) magnetic resonance angiography (MRA) on a 1.0 Tesla magnet, for preoperative definition of the renal arteries. Forty-five preoperative living renal donors underwent CE 3-D FSPGR MRA of the renal vessels and the results were compared with conventional digital subtraction angiography (DSA). The renal vascular anatomy, both normal and with variations, was satisfactorily defined in all 45 cases with CE 3-D FSPGR MRA. Fifteen cases showed an accessory or aberrant arterial supply. A small aneurysm was shown in one case. All cases compared well with conventional DSA. Our study revealed that CE 3-D FSPGR MRA on a lower field strength magnet is accurate in defining the renal vascular anatomy and its variations. Copyright (2005) Blackwell Science Pty Ltd

  11. Magnetic resonance imaging in follow-up assessment of sciatica.

    Science.gov (United States)

    el Barzouhi, Abdelilah; Vleggeert-Lankamp, Carmen L A M; Lycklama à Nijeholt, Geert J; Van der Kallen, Bas F; van den Hout, Wilbert B; Jacobs, Wilco C H; Koes, Bart W; Peul, Wilco C

    2013-03-14

    Magnetic resonance imaging (MRI) is frequently performed during follow-up in patients with known lumbar-disk herniation and persistent symptoms of sciatica. The association between findings on MRI and clinical outcome is controversial. We studied 283 patients in a randomized trial comparing surgery and prolonged conservative care for sciatica and lumbar-disk herniation. Patients underwent MRI at baseline and after 1 year. We used a 4-point scale to assess disk herniation on MRI, ranging from 1 for "definitely present" to 4 for "definitely absent." A favorable clinical outcome was defined as complete or nearly complete disappearance of symptoms at 1 year. We compared proportions of patients with a favorable outcome among those with a definite absence of disk herniation and those with a definite, probable, or possible presence of disk herniation at 1 year. The area under the receiver-operating-characteristic (ROC) curve was used to assess the prognostic accuracy of the 4-point scores regarding a favorable or unfavorable outcome, with 1 indicating perfect discriminatory value and 0.5 or less indicating no discriminatory value. At 1 year, 84% of the patients reported having a favorable outcome. Disk herniation was visible in 35% with a favorable outcome and in 33% with an unfavorable outcome (P=0.70). A favorable outcome was reported in 85% of patients with disk herniation and 83% without disk herniation (P=0.70). MRI assessment of disk herniation did not distinguish between patients with a favorable outcome and those with an unfavorable outcome (area under ROC curve, 0.48). MRI performed at 1-year follow-up in patients who had been treated for sciatica and lumbar-disk herniation did not distinguish between those with a favorable outcome and those with an unfavorable outcome. (Funded by the Netherlands Organization for Health Research and Development and the Hoelen Foundation; Controlled Clinical Trials number, ISRCTN26872154.).

  12. SUBMILLIMETER FOLLOW-UP OF WISE-SELECTED HYPERLUMINOUS GALAXIES

    International Nuclear Information System (INIS)

    Wu Jingwen; Eisenhardt, Peter R. M.; Stern, Daniel; Assef, Roberto; Tsai, Chao-Wei; Cutri, Roc; Griffith, Roger; Jarrett, Thomas; Sayers, Jack; Bridge, Carrie; Benford, Dominic; Blain, Andrew; Petty, Sara; Lake, Sean; Bussmann, Shane; Comerford, Julia M.; Evans, Neal J. II; Lonsdale, Carol; Rho, Jeonghee; Stanford, S. Adam

    2012-01-01

    We have used the Caltech Submillimeter Observatory (CSO) to follow-up a sample of Wide-field Infrared Survey Explorer (WISE) selected, hyperluminous galaxies, the so-called W1W2-dropout galaxies. This is a rare (∼1000 all-sky) population of galaxies at high redshift (peaks at z = 2-3), which are faint or undetected by WISE at 3.4 and 4.6 μm, yet are clearly detected at 12 and 22 μm. The optical spectra of most of these galaxies show significant active galactic nucleus activity. We observed 14 high-redshift (z > 1.7) W1W2-dropout galaxies with SHARC-II at 350-850 μm, with nine detections, and observed 18 with Bolocam at 1.1 mm, with five detections. Warm Spitzer follow-up of 25 targets at 3.6 and 4.5 μm, as well as optical spectra of 12 targets, are also presented in the paper. Combining WISE data with observations from warm Spitzer and CSO, we constructed their mid-IR to millimeter spectral energy distributions (SEDs). These SEDs have a consistent shape, showing significantly higher mid-IR to submillimeter ratios than other galaxy templates, suggesting a hotter dust temperature. We estimate their dust temperatures to be 60-120 K using a single-temperature model. Their infrared luminosities are well over 10 13 L ☉ . These SEDs are not well fitted with existing galaxy templates, suggesting they are a new population with very high luminosity and hot dust. They are likely among the most luminous galaxies in the universe. We argue that they are extreme cases of luminous, hot dust-obscured galaxies (DOGs), possibly representing a short evolutionary phase during galaxy merging and evolution. A better understanding of their long-wavelength properties needs ALMA as well as Herschel data.

  13. Submillimeter Follow-up of Wise-Selected Hyperluminous Galaxies

    Science.gov (United States)

    Wu, Jingwen; Tsai, Chao-Wei; Sayers, Jack; Benford, Dominic; Bridge, Carrie; Blain, Andrew; Eisenhardt, Peter R. M.; Stern, Daniel; Petty, Sara; Assef, Roberto; hide

    2013-01-01

    We have used the Caltech Submillimeter Observatory (CSO) to follow-up a sample of Wide-field Infrared Survey Explorer (WISE) selected, hyperluminous galaxies, the so-called W1W2-dropout galaxies. This is a rare (approximately 1000 all-sky) population of galaxies at high redshift (peaks at zeta = 2-3), which are faint or undetected by WISE at 3.4 and 4.6 micrometers, yet are clearly detected at 12 and 22 micrometers. The optical spectra of most of these galaxies show significant active galactic nucleus activity. We observed 14 high-redshift (zeta greater than 1.7) W1W2-dropout galaxies with SHARC-II at 350-850 micrometers, with nine detections, and observed 18 with Bolocam at 1.1 mm, with five detections. Warm Spitzer follow-up of 25 targets at 3.6 and 4.5 micrometers, as well as optical spectra of 12 targets, are also presented in the paper. Combining WISE data with observations from warm Spitzer and CSO, we constructed their mid-IR to millimeter spectral energy distributions (SEDs). These SEDs have a consistent shape, showing significantly higher mid-IR to submillimeter ratios than other galaxy templates, suggesting a hotter dust temperature.We estimate their dust temperatures to be 60-120 K using a single-temperature model. Their infrared luminosities are well over 10(exp 13) solar luminosity. These SEDs are not well fitted with existing galaxy templates, suggesting they are a new population with very high luminosity and hot dust. They are likely among the most luminous galaxies in the universe.We argue that they are extreme cases of luminous, hot dust-obscured galaxies (DOGs), possibly representing a short evolutionary phase during galaxy merging and evolution. A better understanding of their long-wavelength properties needs ALMA as well as Herschel data.

  14. SUBMILLIMETER FOLLOW-UP OF WISE-SELECTED HYPERLUMINOUS GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Wu Jingwen; Eisenhardt, Peter R. M.; Stern, Daniel; Assef, Roberto [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Tsai, Chao-Wei; Cutri, Roc; Griffith, Roger; Jarrett, Thomas [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Sayers, Jack; Bridge, Carrie [Division of Physics, Math and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Benford, Dominic [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Blain, Andrew [Department of Physics and Astronomy, University of Leicester, LE1 7RH Leicester (United Kingdom); Petty, Sara; Lake, Sean [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA 90095 (United States); Bussmann, Shane [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS78, Cambridge, MA 02138 (United States); Comerford, Julia M.; Evans, Neal J. II [Department of Astronomy, University of Texas, Austin, TX 78731 (United States); Lonsdale, Carol [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Rho, Jeonghee [SETI Institute, 189 BERNARDO Avenue, Mountain View, CA 94043 (United States); Stanford, S. Adam, E-mail: jingwen.wu@jpl.nasa.gov [Department of Physics, University of California Davis, One Shields Avenue, Davis, CA 95616 (United States); and others

    2012-09-01

    We have used the Caltech Submillimeter Observatory (CSO) to follow-up a sample of Wide-field Infrared Survey Explorer (WISE) selected, hyperluminous galaxies, the so-called W1W2-dropout galaxies. This is a rare ({approx}1000 all-sky) population of galaxies at high redshift (peaks at z = 2-3), which are faint or undetected by WISE at 3.4 and 4.6 {mu}m, yet are clearly detected at 12 and 22 {mu}m. The optical spectra of most of these galaxies show significant active galactic nucleus activity. We observed 14 high-redshift (z > 1.7) W1W2-dropout galaxies with SHARC-II at 350-850 {mu}m, with nine detections, and observed 18 with Bolocam at 1.1 mm, with five detections. Warm Spitzer follow-up of 25 targets at 3.6 and 4.5 {mu}m, as well as optical spectra of 12 targets, are also presented in the paper. Combining WISE data with observations from warm Spitzer and CSO, we constructed their mid-IR to millimeter spectral energy distributions (SEDs). These SEDs have a consistent shape, showing significantly higher mid-IR to submillimeter ratios than other galaxy templates, suggesting a hotter dust temperature. We estimate their dust temperatures to be 60-120 K using a single-temperature model. Their infrared luminosities are well over 10{sup 13} L{sub Sun }. These SEDs are not well fitted with existing galaxy templates, suggesting they are a new population with very high luminosity and hot dust. They are likely among the most luminous galaxies in the universe. We argue that they are extreme cases of luminous, hot dust-obscured galaxies (DOGs), possibly representing a short evolutionary phase during galaxy merging and evolution. A better understanding of their long-wavelength properties needs ALMA as well as Herschel data.

  15. Clinical outcome and follow-up of prenatal hydronephrosis

    Directory of Open Access Journals (Sweden)

    Afshin Safaei Asl

    2012-01-01

    Full Text Available Hydronephrosis is probably the most common congenital abnormality detected prenatally by ultrasonography This study was performed to determine the cause and outcome of prenatal hydronephrosis in our hospital. A total of 45 infants, with 57 prenatally hydronephrotic renal units, were enrolled into this study. For the purpose of this study, the degree of hydronephrosis was defined as mild, moderate or severe. Postnatal ultrasonography was performed as soon as possible in those with bilateral hyronephrosis and 3-7 days after birth in those with unilateral hydronephrosis. Voiding cystourethrogram was performed in 6-8 weeks time. In the absence of vesicoureteral reflux (VUR, Diethylenetriamene penta acetate scan was performed to exclude obstructive uropathy. There were 29 males and 16 females (male:female ratio 1.8:1, and unilateral and bilateral hydronephrosis were seen in 33 (73% and 12 (27% of the cases, res-pectively. Hydronephrosis was caused by ureteropelvic junction obstruction (UPJO in 20 (44.5%, VUR in 10 (22.2%, ureterovesical junction obstruction in four (8.9 %, posteriorurethral valves in four (8.9 %, UPJO with VUR in two (4.4% and non-VUR non-obstructive in one (2.2%. During follow-up, 16 patients (35.5% required operative intervention while seven (15.5% improved spontaneously. Fetal hydronephrosis needs close follow-up during both ante-natal and postnatal periods. In this study, the most common cause for hydronephrosis were UPJO and VUR. Also seen in this study is the noteworthy point that mild fetal hydronephrosis is relatively benign and does not require surgical intervention in most cases and surgery should be performed only if there is renal function compromise. Prenatal consultation with a pediatric nephrologist and urologist is useful in decreasing parental anxiety and facilitating postnatal management.

  16. Follow up study and interested cases in subdural hematoma

    International Nuclear Information System (INIS)

    Kano, Mitsumasa; Goh, Jyunto; Koomura, Eiji; Nakao, Kazutami

    1983-01-01

    1. Out of 67 patients ranging from 16 to 82 years old, 20 were followed up by CT scan after operation. 2. Five patients presented hematoma on the both sides after operation, though they had suffered from the lesion of one side before operation. In four patients, hematoma was observed on the both sides before and after operation. Neither preoperative involved side changed nor hematoma appeared on the opposite side after operation in 11 patients. Follow-up examinations lasted up almost three months. 3. The maximum width of the subdural space was divided by the maximum intracranial width. These two factors were measured on horizontal CT scan. The calculated value was expressed in percentage and then, the result was regarded as Subdural Space (SDS) Index. Dividing a difference between the largest SDS Index (before operation) and the smallest by the number of days between the two points gave us a reduction rate of SDS Index. As a result, a reduction rate of 0.4 or less was obtained in all the patients less than 65 years old. There were three patients within the range from 0.7 to 1.0 of the rate. 76-year-old patients showed 2.6 and 5.7. Except the 76-old patients, mean duration of 35.5 days was calculated in Group I and SDS Index was 0, while Group II showed mean duration of 52.4 days, resulting in SDS Index of 0. 4. Specific progresses are shown below: 1) Hemorrhage of the caudate nucleus after operation 2) Subdural effusion of the both sides 3) Appearance of abscess 4) Subtentrial hemorrhage after operation 5) Postoperative epidural hematoma 6) Traumatic intracerebral hemorrhage, resulting in chronic subdural hematoma six months afterward (author)

  17. Hemodynamic evaluation before and after the STA-MCA anastomosis; With special reference to measurement of regional transit time with intra-arterial digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Touho, Hajime; Karasawa, Jun; Shishido, Hisashi; Yamada, Keisuke; Shibamoto, Keiji [Osaka Neurological Inst. Toyonaka (Japan)

    1990-09-01

    Twenty-seven patients with minor completed and major stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The regional cerebral blood flow (rCBF), using inhalation of stable xenon and computed tomographic scanning (Xe{sup s} CT-CBF study), and the mode of transit time (MTT) in the MCA territory using intra-arterial digital aortography were measured. Activated rCBF and MTT was measured 20 minutes after the administration of acetazolamide (10 mg/kg) in 14 patients. Nineteen of the 23 patients with minor stroke (Group 1) showed immediate improvement in their neurological state within a few days of the operation, while four patients with minor stroke (Group 2) and four patients with major stroke (Group 3) showed no improvement. Based on the rCBF obtained with the Xe{sup s} CT-CBF study, affected side rCBF/unaffected side rCBF and %f ((peak DSA number/affected side MTT)/(peak DSA number/unaffected side MTT)) were compared. There was a significant positive correlation. Affected side MTT in Group 1 was 6.41{plus minus}1.16 sec, preoperatively, and significantly decreased to 5.13{plus minus}0.91 sec after the operation. On the other hand, preoperative MTT in Group 2 was 4.40{plus minus}0.81 sec and 4.76{plus minus}0.89 sec, postoperatively. Preoperative %f in Group 1 was 0.514{plus minus}0.143 and significantly increased to 0.739{plus minus}0.154, postoperatively. Group 2 showed no change. Vasodilatory capacity with acetazolamide showed a marked improvement in Group 1, postoperativery. Our study indicated that if MTT is moderately lengthened, %f is moderately decreased, and vasodilatory capacity is impaired, in patients with minor ischemic stroke will benefit from STA-MCA anastomosis. (author).

  18. Longitudinal development of subtraction performance in elementary school.

    Science.gov (United States)

    Artemenko, Christina; Pixner, Silvia; Moeller, Korbinian; Nuerk, Hans-Christoph

    2017-10-05

    A major goal of education in elementary mathematics is the mastery of arithmetic operations. However, research on subtraction is rather scarce, probably because subtraction is often implicitly assumed to be cognitively similar to addition, its mathematical inverse. To evaluate this assumption, we examined the relation between the borrow effect in subtraction and the carry effect in addition, and the developmental trajectory of the borrow effect in children using a choice reaction paradigm in a longitudinal study. In contrast to the carry effect in adults, carry and borrow effects in children were found to be categorical rather than continuous. From grades 3 to 4, children became more proficient in two-digit subtraction in general, but not in performing the borrow operation in particular. Thus, we observed no specific developmental progress in place-value computation, but a general improvement in subtraction procedures. Statement of contribution What is already known on this subject? The borrow operation increases difficulty in two-digit subtraction in adults. The carry effect in addition, as the inverse operation of borrowing, comprises categorical and continuous processing characteristics. What does this study add? In contrast to the carry effect in adults, the borrow and carry effects are categorical in elementary school children. Children generally improve in subtraction performance from grades 3 to 4 but do not progress in place-value computation in particular. © 2017 The British Psychological Society.

  19. Progression of Myopic Maculopathy during 18-Year Follow-up.

    Science.gov (United States)

    Fang, Yuxin; Yokoi, Tae; Nagaoka, Natsuko; Shinohara, Kosei; Onishi, Yuka; Ishida, Tomoka; Yoshida, Takeshi; Xu, Xian; Jonas, Jost B; Ohno-Matsui, Kyoko

    2018-06-01

    To examine the progression pattern of myopic maculopathy. Retrospective, observational case series. Highly myopic patients who had been followed up for 10 years or more. Using fundus photographs, myopic features were differentiated according to Meta-analysis of Pathologic Myopia (META-PM) Study Group recommendations. Progression pattern of maculopathy. The study included 810 eyes of 432 patients (mean age, 42.3±16.8 years; mean axial length, 28.8±1.9 mm; mean follow-up, 18.7±7.1 years). The progression rate of myopic maculopathy was 47.0 per 1000 eye-years. Within the pathologic myopia (PM) group (n = 521 eyes), progression of myopic maculopathy was associated with female gender (odds ratio [OR], 2.21; P = 0.001), older age (OR, 1.03; P = 0.002), longer axial length (OR, 1.20; P = 0.007), greater axial elongation (OR, 1.45; P = 0.005), and development of parapapillary atrophy (PPA; OR, 3.14; P < 0.001). Diffuse atrophy, found in 217 eyes without choroidal neovascularization (CNV) or lacquer cracks (LCs) at baseline, progressed in 111 (51%) eyes, leading to macular diffuse atrophy (n = 64; 64/111 or 58%), patchy atrophy (n = 59; 53%), myopic CNV (n = 18; 16%), LCs (n = 9; 5%), and patchy-related macular atrophy (n = 3; 3%). Patchy atrophy, detected in 63 eyes without CNV or LCs at baseline, showed progression in 60 eyes (95%), leading to enlargement of original patchy atrophy (n = 59; 59/60 or 98%), new patchy atrophy (n = 29; 48%), CNV-related macular atrophy (n = 13; 22%), and patchy-related macular atrophy (n = 5; 8%). Of 66 eyes with LCs, 43 eyes (65%) showed progression with development of new patchy atrophy (n = 38; 38/43 or 88%) and new LCs (n = 7; 16%). Reduction in best-corrected visual acuity (BCVA) was associated mainly (all P < 0.001) with the development of CNV or CNV-related macular atrophy and enlargement of macular atrophy. The most frequent progression patterns were an extension of peripapillary diffuse atrophy to macular diffuse

  20. Diagnosis, surgical treatment and follow-up of thyroid cancers

    International Nuclear Information System (INIS)

    Pacini, F.; Pinchera, A.; Vorontsova, T.; Demidchik, E.P.; Delange, F.; Reiners, C.; Schlumberger, M.

    1996-01-01

    This paper reports the activities and the results of the research carried out by the Centers participating to the JSP4 project, within the framework of the EU program on the consequences of the Chernobyl disaster. The project was aimed to develop and to control the application of basic principles for the diagnosis, treatment and follow-up of thyroid carcinoma, with special attention to the peculiar requirement of children and adolescents. To this purpose, training in Western European Centers was offered to a number of scientists from Belarus, Ukraine and Russia. Several official meetings were organized to share views and to discuss the progress of the project. A basic protocol for the diagnosis, treatment and follow-up of thyroid carcinoma has been developed and approved by all participating Centers. Hopefully, it will be applied to the new cases and to those already under monitoring. A large part of the protocol is dedicated to the post-surgical treatment with thyroid hormones for the suppression of TSH and with calcitriol for the management of surgical hypoparathyroidism. A detailed protocol to asses iodine deficiency and, eventually, to introduce a program of iodine supplementation has been proposed. The collection of control cases of childhood thyroid carcinoma in non-radiation exposed European countries has been initiated in Italy, France and Germany. This data will be used as control for the post-Chernobyl childhood thyroid carcinomas. Here is reported a preliminary comparison of the clinical and epidemiological features of almost all (n=368) radiation-exposed Belarus children who developed thyroid carcinoma (age at diagnosis < 16 years), with respect to 90 children of the same age group, who, in the past 20 years, have received treatment for thyroid carcinoma in two centers in Italy (Pisa and Rome). Finally, by molecular biology, genetic mutations of the RET proto-oncogene have been found in several samples of thyroid carcinomas provided by the Belarus

  1. Optical follow-up of gravitational wave triggers with DECam

    Energy Technology Data Exchange (ETDEWEB)

    Herner, K.; Annis, J.; Berger, E.; Brout, D.; Butler, R.; Chen, H.; Cowperthwaite, P.; Diehl, H.; Doctor, Z.; Drlica-Wagner, A.; Farr, B.; Finley, D.; Frieman, J.; Holz, D.; Kessler, R.; Lin, H.; Marriner, J.; Nielsen, E.; Palmese, A.; Sako, M.; Soares-Santos, M.; Sobreira, F.; Yanny, B.

    2017-10-01

    Gravitational wave (GW) events have several possible progenitors, including black hole mergers, cosmic string cusps, supernovae, neutron star mergers, and black hole{neutron star mergers. A subset of GW events are expected to produce electromagnetic (EM) emission that, once detected, will provide complementary information about their astrophysical context. To that end, the LIGO-Virgo Collaboration has partnered with other teams to send GW candidate alerts so that searches for their EM counterparts can be pursued. One such partner is the Dark Energy Survey (DES) and Dark Energy Camera (DECam) Gravitational Waves Program (DES- GW). Situated on the 4m Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile, DECam is an ideal instrument for optical followup observations of GW triggers in the southern sky. The DES-GW program performs subtraction of new search images with respect to preexisting overlapping images to select candidate sources. Due to the short decay timescale of the expected EM counterparts and the need to quickly eliminate survey areas with no counterpart candidates, it is critical to complete the initial analysis of each night's images within 24 hours. The computational challenges in achieving this goal include maintaining robust I/O pipelines during the processing, being able to quickly acquire template images of new sky regions outside of the typical DES observing regions, and being able to rapidly provision additional batch computing resources with little advance notice. We will discuss the search area determination, imaging pipeline, general data transfer strategy, and methods to quickly increase the available amount of batch computing. We will present results from the rst season of observations from September 2015 to January 2016 and conclude by presenting improvements planned for the second observing season.

  2. Operative correction and follow-up of craniofacial duplication.

    Science.gov (United States)

    Kotrikova, Bibiana; Hassfeld, Stefan; Steiner, Hans H; Hähnel, Stefan; Krempien, Robert; Mühling, Joachim

    2007-03-01

    Anterior craniofacial duplication (diprosopus) is an extremely rare form of conjoined twins. The children share a single trunk with normal extremities and varying degrees of facial malformation. Duplication of specific structures, such as the nose (diprosopus dirrhinus), eyes (diprosopus tetraophthalmus), and ears, is possible. The authors present a case of partial facial duplication (diprosopus dirrhinus) in a male infant. The clinical and radiographic findings and the surgical correction and follow-up are described. In a single surgical session, the authors were able to achieve not only a functionally but also an aesthetically acceptable result. In the postoperative course, the child showed nearly normal growth and satisfactory psychosocial and motor development. However, 40 months postoperatively, we noticed a tendency of the orbitae to diverge (i.e., toward hypertelorism). The surgical management of complex craniofacial malformations such as diprosopus needs a precise morphologic analysis of the patient's deformity followed by a clear treatment plan. A staged reconstructive approach is carried out to coincide with facial growth patterns and brain and eye function. If the interorbital distance in our patient increases progressively, a second operation for reduction of the interorbital distance may be necessary.

  3. [Assessment and follow up of diabetic patients in hemodialysis].

    Science.gov (United States)

    Sanhueza, María Eugenia; Cotera, Alejandro; Elgueta, Leticia; López S, Gloria; Loncon, Patricia; Macan, Fernando; Pérez, Francisco; Cavada, Gabriel; Alvo, Miriam

    2008-03-01

    Despite a better management of the variables that influence the development of diabetic nephropathy there is a progressive increase in the prevalence of terminal renal failure among diabetics, whose cause is not clear. To study in a group of patients in hemodialysis, the quality of diabetes control previous to the entry to dialysis, their physical condition and their evolution. Diabetic patients with at least three months of hemodialysis answered a questionnaire about diabetes control quality previous to dialysis and had physical and laboratory assessment. They were followed for at least four years thereafter. Fifty seven patients aged 62+/-11 years were studied. Eighty four percent had some degree of disability. Eighty seven percent had high blood pressure and 73% had to enter dialysis as an emergency. Mean glycosilated hemoglobin was 7.7% and 58% had a dialysis dose with a Kt/Vofless than 1.2. Fifty eight percent died during follow up. No relationship between mortality and age, blood pressure, glycosilated hemoglobin of Kt/V, was observed. There is an inadequate management of blood glucose and blood pressure of diabetic patients before entry to dialysis. They are referred inverted exclamation markate to the nephrologist, the dialysis dose is insufficient and they have a high mortality.

  4. SDSS-III MARVELS Planet Candidate RV Follow-up

    Science.gov (United States)

    Ge, Jian; Thomas, Neil; Ma, Bo; Li, Rui; SIthajan, Sirinrat

    2014-02-01

    Planetary systems, discovered by the radial velocity (RV) surveys, reveal strong correlations between the planet frequency and stellar properties, such as metallicity and mass, and a greater diversity in planets than found in the solar system. However, due to the sample sizes of extant surveys (~100 to a few hundreds of stars) and their heterogeneity, many key questions remained to be addressed: Do metal poor stars obey the same trends for planet occurrence as metal rich stars? What is the distribution of giant planets around intermediate- mass stars and binaries? Is the ``planet desert'' within 0.6 AU in the planet orbital distribution of intermediate-mass stars real? The MARVELS survey has produced the largest homogeneous RV measurements of 3300 V=7.6-12 FGK stars. The latest data pipeline effort at UF has been able to remove long term systematic errors suffered in the earlier data pipeline. 18 high confident giant planet candidates have been identified among newly processed data. We propose to follow up these giant planet candidates with the KPNO EXPERT instrument to confirm the detection and also characterize their orbits. The confirmed planets will be used to measure occurrence rates, distributions and multiplicity of giants planets around F,G,K stars with a broad range of mass (~0.6-2.5 M_⊙) and metallicity ([Fe/H]~-1.5-0.5). The well defined MARVELS survey cadence allows robust determinations of completeness limits for rigorously testing giant planet formation theories and constraining models.

  5. Bilateral sacrospinous fixation without hysterectomy: 18-month follow-up

    Science.gov (United States)

    Şentürk, Mehmet Baki; Güraslan, Hakan; Çakmak, Yusuf; Ekin, Murat

    2015-01-01

    Objective The aim of this study was to evaluate the results of bilateral sacrospinous fixation (SSF), which was performed with surgical mesh interposition and bilateral vaginal repair. Material and Methods Twenty-two patients underwent SSF between 2010 and 2012, and the results were evaluated retrospectively. The results at preoperative and postoperative 6th, 12th, and 18th months of the pelvic organ prolapse quantification system (POP-Q) and the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire-12 (PISQ-12) were compared using Friedman and Wilcoxon Signed Ranks tests. Values of p<0.05 and <0.01 were considered statistically significant. Results According to the POP-Q, significant healing was observed on all vaginal vault points (p=0.001), and no prolapse was observed until the 18-month follow-up stage. There were also prominent patients who felt satisfactory with respect to their sexual life according to PISQ-12 (p=0.001). Conclusion This technique appears to provide an adequate clinical resolution, and it may be the primary surgical option for women with pelvic organ prolapse. PMID:26097393

  6. Long term follow up in hemodialysis patients with parathyroidectomy

    International Nuclear Information System (INIS)

    Alvarez, A.; Petraglia, A.; Caorsi, H.; Mazzuchi, N.; Olaizola, I.; Acuna, G.; Fajardo, L.; Ambrosoni, P.; Morelli, R.

    1998-01-01

    A retrospective study was performed in 41 patients, in chronic hemodialysis with severe hyperparathyroidism (HPT), who underwent surgery during time period from 1985 to 1997. 22 females, 19 males, aged 50 and 14 years, with PTHI 1345 and 604 pg/ml were followed up 32 and 22 months. Three surgical methods we evaluated: group I) total para thyroidectomy(PTX) with Implants(n=24); group II) subtotal PTX(n=14) and group III) total PTX(n=3). It considered recurrence of HPT when PTH levels were higher than upper range of normal, after 6 months post surgery. persistence was defined when there was no standardization of PTH levels. In group I, 9 patients had normal parathyroid function, 7 had persistent hypoparathyroidism and had hyperparathyroidism (7 recurrences). Group II patients had parathyroid over function in 5 cases (4 persistence s), 5 were normal and 4 hypoparathyroidism. All patients of the third group had hypoparathyroidism. Long term normalization of parathyroid gland activity was achieved in one third of troduccion patients (34,1%) whereas 34,1% permanent hypoparathyroidism and 31,8% hyperparathyroidism. It found no differences in recurrence and histological subtype of parathyroid gland in the different groups. In conclusion, similar long term clinical results were obtained with the different groups. The surgical ideal treatment is controversial. We think that in the long run, the evolution of parathyroid status is mostly influenced by the persistence of uremic state rather than the type of surgery performed [es

  7. Congenital cytomegalovirus infection: treatment, sequelae and follow-up.

    Science.gov (United States)

    Lombardi, Giuseppina; Garofoli, Francesca; Stronati, Mauro

    2010-10-01

    Cytomegalovirus (CMV) is the most common cause of congenital infection affecting about 1% of all the live births worldwide. Its prevalence in the developed world seems to be slightly lower, ranging between 0.6 and 0.7%. Symptoms can be detected at birth in 10-15% of the congenitally infected of which 50-90% will develop sequelae, the most frequent being sensorineural hearing loss (SNHL), visual defect, psychomotor impairment, mental retardation, cerebral palsy and seizures. Eighty-five to 90% of the infected newborns are asymptomatic but 10-15% of them are equally at risk for sensorineural sequelae, like 20-30% of all the infected children. Therefore it is important a time prolonged and closer follow-up of infected children that we propose should be until 6 years of age. This should lead to an early intervention, better management and eventually even control the long-term sequelae. Infants born with symptomatic congenital infection have a worse prognosis than those with no evidence of clinical disease, and ganciclovir (GCV) intravenous 6 mg/kg every 12 h for 6 weeks is the most used therapy for symptomatic newborns. Valganciclovir (V-GCV) syrup is a pro-drug of GCV and presents high oral bioavailability. To date, it is possible to administer this drug at home, and the tolerability profile may allow for wider indications and longer treatments.

  8. Patients’ follow-up using biomechanical analysis of rehabilitation exercises

    Directory of Open Access Journals (Sweden)

    Bruno Bonnechère

    2017-03-01

    Full Text Available Thanks to the evolution of game controllers video games are becoming more and more popular in physical rehabilitation. The integration of serious games in rehabilitation has been tested for various pathologies. Parallel to this clinical research, a lot of studies have been done in order to validate the use of these game controllers for simple biomechanical evaluation. Currently, it is thus possible to record the motions performed by the patients during serious gaming exercises for later analysis. Therefore, data collected during the exercises could be used for monitoring the evolution of the patients during long term rehabilitation. Before using the parameters extracted from the games to assess patients’ evolution two important aspects must be verified: the reproducibility of measurement and a possible effect of learning of the task to be performed. Ten healthy adults played 9 sessions of specific games developed for rehabilitation over a 3-weeks period. Nineteen healthy children played 2 sessions to study the influence of age. Different parameters were extracted from the games: time, range of motion, reaching area. Results of this study indicates that it is possible to follow the evolution of the patients during the rehabilitation process. The majority of the learning effect occurred during the very first session. Therefore, in order to allow proper regular monitoring, the results of this first session should not be included in the follow-up of the patient.

  9. Bradykinesia in Huntington's disease. A prospective, follow-up study.

    Science.gov (United States)

    García Ruiz, Pedro J; Hernández, Jaime; Cantarero, Susana; Bartolomé, Manuel; Sánchez Bernardos, Vicenta; García de Yébenez, Justo

    2002-04-01

    Bradykinesia is a frequent finding in Huntington's disease (HD), but some aspects are presently unknown; including the natural evolution of bradykinesia over time and the correlation between bradykinesia and functional capacity. We studied the motor performance of 20 genetically confirmed patients with HD (age: 40+/-10.8 years; age at onset 33.6+/-11 years; total functional capacity (TFC): 9.57+/-3; UHDRS total motor scale: 31.4+/-13, triplet length (CAG)n: 46.7+/-4 triplets). These patients were studied in baseline conditions and after 18.7+/-6 months of follow-up. In addition, HD patients were compared with 20 age-matched normal controls. Motor study included the four CAPIT timed tests commonly used for Parkinson's disease: pronation-supination (PS), finger dexterity (FD), movement between two points (MTP) and walking test (WT). HD patients were significantly slower than controls in all motor tasks. A significant deterioration occurred over time in three of the four motor tasks (especially FD and WT). A significant correlation between timed tests and TFC score was found (for MTP, r: -0.845; p < 0,0001). In addition a significant correlation between timed tests and the UHDRDS total motor scale was also found (for MTP, r: 0.864; p < 0.0001). In conclusion, simple timed motor tests can detect a deterioration of motor activity over time in HD. Timed tests might be useful to follow the natural evolution of HD and to assess the efficacy of new therapies.

  10. Measles vaccine: a 27-year follow-up.

    LENUS (Irish Health Repository)

    Ramsay, M E

    1994-04-01

    In 1964, the Medical Research Council undertook a trial of measles vaccine in over 36,000 United Kingdom children; 9577 of whom received live vaccine, 10,625 received inactivated followed by live vaccines, and 16,328 acted as unvaccinated controls. Participants in this study have been followed to determine the long term protection from measles vaccine and follow-up data were available on 4194, 4638 and 274 respectively. During the 5-year period 1986-90, the protective efficacy of live measles vaccine has remained high at 87%, but the 95% confidence interval was wide (-43 to 99%) due to the small numbers of cases. Between 1976 and 1990, however, the overall efficacy of the live vaccine was 92% (95% confidence interval 86 to 95%) and there was no evidence of a decline in efficacy (P = 0.13) over the 15-year period. This study suggests that the protection from live measles vaccine persists for up to 27 years after vaccination, and that no change in the current United Kingdom measles immunization policy should be made on the grounds of waning immunity.

  11. Follow-up Sonography after Sonoguided Renal Biopsy

    International Nuclear Information System (INIS)

    Kim, Hyung Soo; Park, Cheol Min; Cha, In Ho

    1996-01-01

    To assess ultrasonographic findings and clinical significance after renal biopsy. 174 cases of post-biopsy sonography were studied retrospectively. We classified post-biopsy hematoma on the basis of their size as small (thickness less than 1 cm, length less than 3cm), medium (thickness less than 1cm, length greater than 3 cm), large (thickness greater than 1 cm, length greater than 3 cm). We also compared bleeding parameters (prothrombin time, partial thromboplastin time) and renal function in both cases which had hematoma or not. Total 33 hematomas were found (19%). Small hematoma was observed in 14 cases, medium hematoma in 16 cases, large hematoma in 3 cases. Severe complications requiring prompt therapy occurred in 1 case(0.6%). In 6 cases hematocrit fell by more than 4%, all of these hematomas were observed on US. Severe complications after sonoguided renal biopsy were rare. There was poor correlation between prebiopsybleeding parameter, renal function and post-biopsy hematomas. And sonography is considered as adequate method for follow up of post-biopsy hematoma

  12. Follow-up study on energy entrepreneurs; Laempoeyrittaejaet seurannassa

    Energy Technology Data Exchange (ETDEWEB)

    Solmio, H

    1995-11-01

    Energy supplying (i.e. wood and peat fuels) is a new form of entrepreneurship in which one or more entrepreneurs attend to the supply of energy to local buildings. At present there are about ten localities where this is practised. TTS Institute is engaged in a follow-up study of a chipfired heating system with energy entrepreneurs supplying the chipped wood. The study is part of the nationwide Bioenergy research programme. The targets of the study, three in number during the 1993-94 heating season, are rural schools located in southern and eastern Finland. The primary fuel used to heat these premises is chipped wood made from small-diameter timber with light fuel oil as the supplementary fuel. The entrepreneurs supplying the chip fuel are local farmers, and they both delivered the fuel and attended to the actual heating. The time consumed in transporting the chipped wood to the heating plant and to attend to the actual heating was 0,1-1,1 h/MWh with the work associated with heating representing 0,2-0,5 h/MWh. The productivity of fuelwood harvesting in the study sites was 0,4-0,8 m{sup 3}/h and the productivity of chipping was 3,8-7,5 loose m{sup 3}/h. TTS Institute expanded the study in 1994 to also include a few premis