WorldWideScience

Sample records for cineradiography

  1. Fuel-motion diagnostics and cineradiography

    International Nuclear Information System (INIS)

    Nuclear and non-nuclear applications of cineradiography are reviewed, with emphasis on diagnostic instrumentation for in-pile transient-reactor safety testing of nuclear fuel motion. The primary instrument for this purpose has been the fast-neutron hodoscope, which has achieved quantitative monitoring of time, location, mass, and velocity of fuel movement under the difficult conditions associated with transient-reactor experiments. Alternative diagnostic devices that have been developed have not matched the capabilities of the hodoscope. Other applications for the fuel-motion diagnostic apparatus are also evolving, including time-integrated radiography and direct time- and space-resolved fuel-pin power monitoring. Although only two reactors are now actively equipped with high-resolution fuel-motion diagnostic systems, studies and tests have been carried out in and for many other reactors

  2. Fuel-motion diagnostics and cineradiography

    Energy Technology Data Exchange (ETDEWEB)

    DeVolpi, A.

    1982-09-01

    Nuclear and non-nuclear applications of cineradiography are reviewed, with emphasis on diagnostic instrumentation for in-pile transient-reactor safety testing of nuclear fuel motion. The primary instrument for this purpose has been the fast-neutron hodoscope, which has achieved quantitative monitoring of time, location, mass, and velocity of fuel movement under the difficult conditions associated with transient-reactor experiments. Alternative diagnostic devices that have been developed have not matched the capabilities of the hodoscope. Other applications for the fuel-motion diagnostic apparatus are also evolving, including time-integrated radiography and direct time- and space-resolved fuel-pin power monitoring. Although only two reactors are now actively equipped with high-resolution fuel-motion diagnostic systems, studies and tests have been carried out in and for many other reactors.

  3. Cineradiography in normal and abnormal pharyngo-esophageal deglutition

    International Nuclear Information System (INIS)

    With the aid of high-speed cineradiography the pharyngeal stage of deglutition was examined among 150 volunteers without dysphagia in order to evaluate the radiographic pattern of normal deglutition. In order to evaluate the dignostic result of cineradiographic examinations of the pharyngeal stage of deglutition among dysphagial patients 250 such patients were consecutively examined with an identical technique as the volunteers. The result of the investigation has shown that high-speed cineradiography is a convenient radiologic method for studying normal and abnormal deglutition. In nondysphagial individuals the pharyngeal stage of deglutition is executed with precision, smoothness and obviously with efficiency. In a few individuals without swallowing complaints circumscribed functional aberrations can be registered. In the majority of patients with dysphagia high-speed cineradiography is able to detect functional abnormalities during deglutition. An examination of such patients with this techique is therefore indispensable in order to disclose a probable cause of their complaints. (Auth.)

  4. Examination of swallowing disorders using Digital Cine-Radiography (DCR)

    International Nuclear Information System (INIS)

    Twenty-seven patients with different swallowing disorders were studied by employing Digital Cine-Radiography (DCR) for rapid imaging of the pharynx with a temporal resolution of up to 50 frames per second and a maximum spatial resolution of 0.8 per/mm. To facilitate therapy planning, the DCR study can be transferred to the oto-rhino-laryngologist via videotape. DCR is capable to substitute analog cine or videotechniques in the pre- and postoperative examination of patients with swallowing disorders. (orig.)

  5. Functional property of the cardiac valve prosthesis evaluated in vivo by cine-radiography

    International Nuclear Information System (INIS)

    Functional property of the convexo-concave Bjoerk-Shiley cardiac valve prosthesis implanted in the mitral position of 21 patients was investigated by integrated cine-radiography repeated for a long term after operation. The maximum opening angle of the tilting disc was 58 ± 2 deg, and was not affected by atrial fibrillation nor by tachycardia up to 160 bpm. There was no change in the maximum opening angle of the disc observed during follow-up period. Good correlation between shortning of the disc opening time and increase in pulse rate suggests excellent adaptation of this prosthesis for tachycardia induced by exercise or electric pacing. However, atrial fibrillation causes time delay in disc closure immediately after prolonged R-R interval. Disc rotation alleviating disc wear was observed in all the patients whether it moves slow or quick. Dysfunction of the disc opening can be readily determined not only by measuring the maximum disc opening angle, but also by observing the characteristic movement indicated in this study. It is concluded from these results that clinical apprication for the convexo-concave Bjoerk-Shiley valve prosthesis is appropriate and cine-radiography is an useful non-invasive examination of cardiac valve prosthesis for long follow-up period. (author)

  6. Analyses of the mouthpart kinematics in Periplaneta americana (Blattodea, Blattidae) using synchrotron-based X-ray cineradiography.

    Science.gov (United States)

    Schmitt, Christian; Rack, Alexander; Betz, Oliver

    2014-09-01

    The kinematics of the biting and chewing mouthparts of insects is a complex interaction of various components forming multiple jointed chains. The non-invasive technique of in vivo cineradiography by means of synchrotron radiation was employed to elucidate the motion cycles of the mouthparts in the cockroach Periplaneta americana. Digital X-ray footage sequences were used in order to calculate pre-defined angles and distances, each representing characteristic aspects of the movement pattern. We were able to analyze the interactions of the mouthpart components and to generate a functional model of maxillary movement by integrating kinematic results, morphological dissections and fluorescence microscopy. During the opening and closing cycles, which take about 450-500 ms on average, we found strong correlations between the measured maxillary and mandibular angles, indicating a strong neural coordination of these movements. This is manifested by strong antiphasic courses of the maxillae and the mandibles, antiphasic patterns of the rotation of the cardo about its basic articulation at the head and by the deflection between the cardo and stipes. In our functional model of the maxilla, its movement pattern is explained by the antagonistic activity of four adductor-promotor muscles and two abductor-remotor muscles. However, beyond the observed intersegmental and bilateral stereotypy, certain amounts of variation across subsequent cycles within a sequence were observed with respect to the degree of correlation between the various mouthparts, the maximum, minimum and time course of the angular movements. Although generally correlated with the movement pattern of the mandibles and the maxillary cardo-stipes complex, such plastic behaviour was especially observed in the maxillary palpi and the labium. PMID:24948639

  7. Cineradiography of the liquid bolus swallow. A study of the speed ot the bolus and peristaltic wave and of movement of the hyoid bone, larynx, and epiglottis

    International Nuclear Information System (INIS)

    In the evaluation of the dysphagic patient, radiology is crucial as a technique for monitoring morphology and function. In particular, high-speed cineradiography can reveal a variety of pharyngeal dysfunctions. However, in the literature and in practice the difference between normal and abnormal function is not always clear. This monography is based on high-speed cineradiographies of swallowing in 75 non-dysphagic volunteers and in 189 dysphagic patients. The purpose was to study whether differences in bolus volumes, patient position, age and gender had any effects on the following parameters: the speed of the peristaltic wave and apex of the liquid barium bolus, the length of movement and the movement pattern of the hyoid bone and larynx, and epiglottic function. The study disclosed that the speed of the bolus, the anterior-superior movement and net movement of the hyoid bone increased significantly with larger bolus volumes. The position of the individual in relation to gravity significantly influenced the speed of peristalsis. In most of the measured parameters there were no differences between non-dysphagic and dysphagic individuals expect for differences in the intrapersonal variations and in the anterior-superior movement of the hyoid bone. In patients with pharyngeal dysfunction the initial stage of the elevation of the larynx was significantly lower than in patients without dysfunction. The approximation of the thyroid cartilage to the hyoid bone was significantly greater in individuals with normal epiglottic function than in those with epiglottic dysmobility. It is suggested that abnormal speed of peristalsis may be a mild form of dysfunction. Measurements of the aforementioned speed and movements can be done if bolus volume, age and position of the patient, film speed and magnifications factors are known. Hypotheses concerning epiglottic function and central control of swallowing are proposed. (au)

  8. Feasibility of investigating the mechanisms of aortic trauma using high-speed cineradiography. A pilot study. Final report, 15 May--31 August 1977

    International Nuclear Information System (INIS)

    A pilot study was performed to evaluate use of the HSRI high-speed cineradiographic system for study of aortic trauma mechanisms. The thoraxes of anesthetized New Zealand white rabbits were impacted by a dropped accelerometer-instrumented, 1.5 kg mass from a height of 2.44 meters. Velocity and force data were obtained from the instrumented impacting mass. High-speed cineradiographs at approximately 1000 frames per second showed thoracic skeletal deformation and heart, diaphragm, and liver displacements. No radiopaque contrast medium was used in this preliminary investigation. Post-impact autopsy revealed rib fracture, localized hemorrhaging, and aortic transection. On the basis of film obtained, this method has potential for the study of internal organ injury mechanisms

  9. Cine MRI: a new approach to the diagnosis of scapholunate dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Langner, I.; Eisenschenk, A. [University Medicine Greifswald, Division of Hand Surgery and Functional Microsurgery, Department of Trauma and Reconstructive Surgery, Greifswald (Germany); Fischer, S.; Langner, S. [University Medicine Greifswald, Institute for Diagnostic Radiology and Neuroradiology, Greifswald (Germany)

    2015-08-15

    To evaluate the feasibility of cine MRI for the detection of scapholunate dissociation (SLD) and to compare the sensitivity and specificity of cine MRI with those of cineradiography and arthroscopy. To evaluate feasibility, healthy subjects underwent cine MRI of the wrist. To evaluate sensitivity and specificity, patients with clinically suspected scapholunate ligament (SLL) injury after trauma to the wrist were prospectively included and underwent radiographic examination, cineradiography, and cine MRI. In 25 out of 38 patients, subsequent arthroscopy was performed. Results of cineradiography and cine MRI correlated with those of arthroscopy. Cine MRI was of diagnostic quality in all healthy subjects and patients with good interrater agreement. There was excellent correlation between cineradiography and cine MRI. Scapholunate distance differed significantly between healthy subjects and patients with scapholunate dissociation (p < 0.001), but not between imaging modalities in the patient group. Cine MRI had 85 % sensitivity and 90 % specificity for the detection of SLD. Cine MRI of the wrist is a fast and reliable technique for the detection of SLD with diagnostic accuracy comparable to cineradiography. It can be easily implemented as a routine clinical MRI examination, facilitating diagnostic workup of patients with suspected SLD while avoiding radiation exposure. (orig.)

  10. Atlantoaxial subluxation after otoplasty.

    LENUS (Irish Health Repository)

    Kelly, E J

    2012-02-03

    A case of iatrogenic atlantoaxial subluxation after bilateral otoplasty is presented. Cineradiography was required for definitive diagnosis. Bed rest and Halter traction successfully resolved the condition. Great care is required while turning the head during skin preparation, draping, planning, and surgery, especially in young children. A high index of suspicion is necessary when a child develops torticollis after otoplasty.

  11. Functional and morphological changes in the pharynx in achalasia and in diffuse esophageal spasm

    International Nuclear Information System (INIS)

    Since the pharynx and the esophagus are a functional unit, functional radiodiagnosis has to be directed at pharyngo-esophageal interaction. Among our collective of 73 patients suffering from achalasia or diffuse esophageal spasm, we were able to recognize a substantially increased incidence of morphological or functional pharyngeal disorders by means of cineradiography. The functional alterations in particular were often not revealed by conventional fluoroscopy. High-speed cineradiography, with its high temporal and spatial resolution, turned out to be a valuable tool in analysis of the origin of pharyngeal dysphagia. Manometry correlated very well with the radiologic findings in tubular esophagus, but proved unreliable in the detection of alterations of the upper esophageal sphincter region, because of problems inherent in the method. Furthermore, membranous stenosis (webs), lateral or dorsal diverticula, and asymmetry of the pharynx were observed strikingly often. (orig.)

  12. Functional and morphological changes in the pharynx in achalasia and in diffuse esophageal spasm

    Energy Technology Data Exchange (ETDEWEB)

    Hannig, C.; Wuttge-Hannig, A.; Amon, K.; Feussner, H.

    1989-08-01

    Since the pharynx and the esophagus are a functional unit, functional radiodiagnosis has to be directed at pharyngo-esophageal interaction. Among our collective of 73 patients suffering from achalasia or diffuse esophageal spasm, we were able to recognize a substantially increased incidence of morphological or functional pharyngeal disorders by means of cineradiography. The functional alterations in particular were often not revealed by conventional fluoroscopy. High-speed cineradiography, with its high temporal and spatial resolution, turned out to be a valuable tool in analysis of the origin of pharyngeal dysphagia. Manometry correlated very well with the radiologic findings in tubular esophagus, but proved unreliable in the detection of alterations of the upper esophageal sphincter region, because of problems inherent in the method. Furthermore, membranous stenosis (webs), lateral or dorsal diverticula, and asymmetry of the pharynx were observed strikingly often. (orig.).

  13. Radiological differential diagnosis in chronic aspiration pneumonia

    International Nuclear Information System (INIS)

    6% of all patients suffering from a cerebro-vascular injury die from aspiration pneumonia within the first year. The high temporal resolution of high-speed cineradiography (HFK) (50 frames/sec.) allows the recording of the 0.7 sec. process of pharyngeal swallow. Five case-examples are presented (total number of cases: 95) illustrating the possibility of differentiation between three types of aspiration by means of cineradiography. These types are the so-called pre-, intra- and postdeglutitive aspiration, that is aspiration before or after triggering of the swallowing reflex. This differentiation is of great therapeutic importance. The analysis of disturbances of pharyngo-laryngeal motility and the temporal coordination allows setting up individual surgical and/or conservative programme for rehabilitation. (orig.)

  14. Archosaurian respiration and the pelvic girdle aspiration breathing of crocodyliforms

    OpenAIRE

    Claessens, Leon P.A.M.

    2009-01-01

    Birds and crocodylians, the only living archosaurs, are generally believed to employ pelvic girdle movements as a component of their respiratory mechanism. This in turn provides a phylogenetic basis for inferring that extinct archosaurs, including dinosaurs, also used pelvic girdle breathing. I examined lung ventilation through cineradiography (high-speed X-ray filming) and observed that alligators indeed rotate the pubis to increase tidal volume, but did not observe pelvic girdle movement co...

  15. Analysis and radiological staging of the type and degree of severity in aspiration

    International Nuclear Information System (INIS)

    The high temporal resolution of cineradiography with frame rates of the complex process of pharyngeal swallowing lasting 0.7 s. The method enables us to differentiate between socalled pre-, intra- and postdeglutitive aspiration, which means aspiration before, during and after the triggering of the swallowing reflex. Together with an estabilshed score for the severeness of the aspiration, the method supplies important data for setting up a functional surgical and/or conservative program for rehabilitation and for follow-up-studies. (orig.)

  16. A large-scale multicentre study in Belgium of dose area product values and effective doses in interventional cardiology using contemporary X-ray equipment.

    Science.gov (United States)

    Bogaert, E; Bacher, K; Thierens, H

    2008-01-01

    In this paper, a large-scale multicentre patient dose study performed in eight Belgian interventional cardiology departments is presented. Effective dose (E) was calculated based on a detailed dose-area product (DAP)-registration during each procedure and by using conversion coefficients generated by the Monte Carlo-based computer program PCXMC. Conversion coefficients were found to be 0.177 mSv Gycm(-2) for systems that do not use any additional copper filtration in cineradiography and 0.207 mSv Gycm(-2) for systems that use additional copper filtration in cineradiography. Mean E values of 9.6 and 15.3 mSv for diagnostic and therapeutic procedures, respectively, were obtained. DAP distributions were investigated in order to derive dose reference levels: 71 and 106 Gycm2 for diagnostic and therapeutic procedures, respectively, are proposed. Significant differences were observed in DAP distributions taking into account whether additional copper filtration was used in the cineradiography mode. Apart from the skin, the organs most at risk are lungs and heart. The probability of fatal cancer for the studied population amounted to 1.1x10(-4) and 2.1x10(-4) for diagnostic and therapeutic procedures, respectively, for the age distribution of the patients considered in this multicentre study. PMID:17681964

  17. Dynamic and ultrastructural study of sphincter of Oddi in early-stage cholelithiasis in rabbits with hypercholesterolemia

    Institute of Scientific and Technical Information of China (English)

    Jing Guo Wei; Yao Cheng Wang; Fan Du; Hou Jun Yu

    2000-01-01

    AIM To study the relationship between preformation of gallstone and the kinetics and ultrastructure of sphincter of Oddi.METHODS Adult female rabbits were used and divided into 3 groups, and fed with either normal or high cholesterol diet for four or eight weeks.Each group contained eight rabbits. The manometry of sphincter of Oddi, biliary cineradiography, gallbladder volume measurement and ultrastructure observation under electron microscope were performed.RESULTS In groups Ⅰ and Ⅱ, the basal pressure in low-pressure ampulla or high pressure zone of sphincter of Oddi was elevated, the amplitude of phasic contraction was decreased and the volume of gallbladder were increased, with a significant difference (P<0.01) from those of control. Gallstones were found in group Ⅱ rabbits (7/8). Under cineradiography, low-pressure ampulla showed a spasmodic status without apparent peristaltic contraction. Under electron microscope, inside the muscular cells of sphincter of Oddi,loosening of microfilament and swelling of plasmosomes which congregated at the top were observed. The amount showed no obvious change under nitric oxide synthase (NOS) stain.CONCLUSION Twisting of the microfilament and disarrangement of kink macula densa inside the muscular cells suggested that the sphincter of Oddi was under spasmodic status. The impaired diastolic function caused and aggravated the stasis of cystic bile. The swelling plasmosome could be one of the important factors in elevating the tonic pressure of sphincter of Oddi.

  18. High speed photography, videography, and photonics III; Proceedings of the Meeting, San Diego, CA, August 22, 23, 1985

    Science.gov (United States)

    Ponseggi, B. G. (Editor); Johnson, H. C. (Editor)

    1985-01-01

    Papers are presented on the picosecond electronic framing camera, photogrammetric techniques using high-speed cineradiography, picosecond semiconductor lasers for characterizing high-speed image shutters, the measurement of dynamic strain by high-speed moire photography, the fast framing camera with independent frame adjustments, design considerations for a data recording system, and nanosecond optical shutters. Consideration is given to boundary-layer transition detectors, holographic imaging, laser holographic interferometry in wind tunnels, heterodyne holographic interferometry, a multispectral video imaging and analysis system, a gated intensified camera, a charge-injection-device profile camera, a gated silicon-intensified-target streak tube and nanosecond-gated photoemissive shutter tubes. Topics discussed include high time-space resolved photography of lasers, time-resolved X-ray spectrographic instrumentation for laser studies, a time-resolving X-ray spectrometer, a femtosecond streak camera, streak tubes and cameras, and a short pulse X-ray diagnostic development facility.

  19. The upper esophageal sphincter during normal deglutition

    International Nuclear Information System (INIS)

    The upper esophageal sphincter was studied during deglutition in 7 healthy subjects using simultaneous cineradiography and manometry. The pressure measuring device consisted of 3 sensors distally placed, and separated by 10 mm. They recorded pressure obliquely to the right at an angle of 15 to 45 degrees anteriorly. During the swalloing sequence a pressure sensor initially placed in the high pressure zone of the sphincter easily slid out of position due to asynchronous movements of the sphincter and the pressure measuring device. These movements can result in erroneous interpretation of pressure recordings. Continuous radiologic monitoring during the entire swallowing sequence thus seems to be mandatory. Immediately before the bolus entered the upper esophageal sphincter, the sphincter relaxed and low or even negative pressures were registered. When the bolus had passed onwards the sphincter contracted gradually, to resume its pre-swallow pressure. (orig.)

  20. Radiologic evaluation of the oral stage of swallowing

    Energy Technology Data Exchange (ETDEWEB)

    Ekberg, O.; Hillarp, B.

    The oral stage of swallowing was radiologically evaluated in 19 patients with swallowing complaints. Eight patients had had surgical resection and reconstruction due to tumours of the tongue, floor of the mouth or mandible. Eleven patients had suffered from cerebrovascular disease. All patients had incoordination of tongue movements including defective initiation of pharyngeal swallow. In patients who had undergone surgical resection, oral dysfunction correlated with the extension of resection as well as type of reconstruction, and was more profound compared with the disorder present in patients with cerebrovascular disease. Moreover, muscular derangement due to surgery of the floor of the mouth interfered with the elevation of the hyoid bone, larynx and pharynx and thereby the pharyngeal stage of swallowing also became abnormal. Cineradiography seems to be an appropriate method for evaluation of the oral stage of swallowing in patients with deglutition complaints.

  1. Essential Segmental Myoclonus Responding Well To Fluoxetine A case Report

    Directory of Open Access Journals (Sweden)

    Bhattacharyya K B

    1999-01-01

    Full Text Available We report a case of essential segmental myoclonus a 10 year old girl who presented with continuing movement of both the shoulder girdle muscles for 6 months. The movements were exacerbated with the hands raised above the head or in the outstretched posture and were persisting during sleep. There was no abnormal palatal movement. Additionally there was a rhythmical clicking sound arising from the shoulders that could be felt and ausculated with the stethoscope. CT scan of brain and MRI of cervical spine were non-contributory, EMG showed muscle activates at about 50 per second in the shoulder girdle muscles. Cine-radiography of shoulder joints showed the head of humerus hitting against the spine of the scapula rhythmically. Spinal tap was non-contributory. The diagnosis or essential segmental myoclonus was entertained and the subject with fluoxetine, a selective serotonin reuptake inhibitor with remarkable response. The possible mechanism of action of agents modulating the serotonergic system in the brain for the management of myoclonus has been reviewed and their role suggested.

  2. Cineradiographic Analysis of Mouse Postural Response to Alteration of Gravity and Jerk (Gravity Deceleration Rate

    Directory of Open Access Journals (Sweden)

    Katsuya Hasegawa

    2014-04-01

    Full Text Available The ability to maintain the body relative to the external environment is important for adaptation to altered gravity. However, the physiological limits for adaptation or the disruption of body orientation are not known. In this study, we analyzed postural changes in mice upon exposure to various low gravities. Male C57BL6/J mice (n = 6 were exposed to various gravity-deceleration conditions by customized parabolic flight-maneuvers targeting the partial-gravity levels of 0.60, 0.30, 0.15 and μ g (<0.001 g. Video recordings of postural responses were analyzed frame-by-frame by high-definition cineradiography and with exact instantaneous values of gravity and jerk. As a result, the coordinated extension of the neck, spine and hindlimbs was observed during the initial phase of gravity deceleration. Joint angles widened to 120%–200% of the reference g level, and the magnitude of the thoracic-curvature stretching was correlated with gravity and jerk, i.e., the gravity deceleration rate. A certain range of jerk facilitated mouse skeletal stretching efficiently, and a jerk of −0.3~−0.4 j (g/s induced the maximum extension of the thoracic-curvature. The postural response of animals to low gravity may undergo differential regulation by gravity and jerk.

  3. Cineradiographic analysis of mouse postural response to alteration of gravity and jerk (gravity deceleration rate).

    Science.gov (United States)

    Hasegawa, Katsuya; de Campos, Priscila S; Zeredo, Jorge L; Kumei, Yasuhiro

    2014-01-01

    The ability to maintain the body relative to the external environment is important for adaptation to altered gravity. However, the physiological limits for adaptation or the disruption of body orientation are not known. In this study, we analyzed postural changes in mice upon exposure to various low gravities. Male C57BL6/J mice (n = 6) were exposed to various gravity-deceleration conditions by customized parabolic flight-maneuvers targeting the partial-gravity levels of 0.60, 0.30, 0.15 and μ g (definition cineradiography and with exact instantaneous values of gravity and jerk. As a result, the coordinated extension of the neck, spine and hindlimbs was observed during the initial phase of gravity deceleration. Joint angles widened to 120%-200% of the reference g level, and the magnitude of the thoracic-curvature stretching was correlated with gravity and jerk, i.e., the gravity deceleration rate. A certain range of jerk facilitated mouse skeletal stretching efficiently, and a jerk of -0.3~-0.4 j (g/s) induced the maximum extension of the thoracic-curvature. The postural response of animals to low gravity may undergo differential regulation by gravity and jerk. PMID:25370191

  4. Time Resolved 2D X-Ray Densitometry of a Ventilated Partial Cavity Closure

    Science.gov (United States)

    Makiharju, Simo; Ceccio, Steven

    2011-11-01

    A time resolved x-ray densitometry system was developed to measure the spatial distribution of void fraction for nominally two-dimensional flows. The system can image a region of (15 cm)2 at a frame rate of up to 4000 fps. The source was a rotating anode type normally used for cineradiography and angiography. Supplied by a 65 kW high frequency generator with a high speed starter, it could be operated at up to 433 mA at 150 kV. The imager subsystem comprised of a high speed camera coupled with a high resolution image intensifier. The range of measured void fraction can be changed to span a desired range yielding an uncertainty on the order of 1% of the measurement range. The system is used to examine the void fraction field in the closure region of a ventilated partial cavity behind a backward facing step. The cavity has Reynolds number of O(105) based on the cavity length, and a non-dimensional gas flux of Q* = 0.0048. The bubbly flow created in the cavity wake is examined using the x-ray densitometry system, duel fiber optical probes, and high speed cinematography. The local void fraction and bubble size distributions in the cavity wake are determined, and the measurements methods are compared. The research was sponsored by ONR under grant N00014-08-1-0215, program manager Dr. L. Patrick Purtell.

  5. Kinematics of intraoral transport and swallowing in the herbivorous lizard uromastix acanthinurus

    Science.gov (United States)

    Herrel; Vree

    1999-05-01

    The kinematics of intraoral transport and swallowing in lizards of the species Uromastix acanthinurus (Chamaeleonidae, Leiolepidinae) were investigated using cineradiography (50 frames s-1). Additional recordings were also made using high-speed (500 frames s-1) and conventional video systems (25 frames s-1). Small metal markers were inserted into different parts of the upper and lower jaw and the tongue. Cineradiographic images were digitised, and displacements of the body, head, upper and lower jaw and the tongue were quantified. Twenty additional variables depicting displacements and the timing of events were calculated. Multivariate analyses of variance indicated significant differences between feeding stages. Remarkably, only very few food-type-dependent differences were observed during intraoral transport, and no such differences could be demonstrated during swallowing. Using previously published data for the closely related insectivorous lizard Plocederma stellio, the effect of dietary specialisation in U. acanthinurus on the kinematic variables while eating locusts was examined. Species differed in a number of gape- and tongue-related variables. These differences may be related to differences in tongue structure between the species. Clearly, U. acanthinurus possesses a specialised gut and dental structure that allows them efficiently to cut pieces from whole leaves. However, a decrease in modulatory capacity seems to be a consequence of dietary specialisation in Uromastix acanthinurus. PMID:10101110

  6. Optimization of radiation protection in pediatric cardiac catheterization procedures

    International Nuclear Information System (INIS)

    used in the dose assessment. The procedures considered in the study are: diagnostic, pulmonary stenting, COA dilatation and PDA occlusion. The average of the total dose area product (DAP) value per procedure was determined and the factors that affected the DAP were investigated. The cumulative dose (CD) of each patient and the effective dose were estimated from the DAP values corrected for patient size. The Pearson correlation of the DAP values with patient equivalent cylindrical diameter (ECD), weight and fluoroscopy time was determined and evaluated. The study shows that the exposure parameters (kVp, mA and fluoroscopy time) and the contribution of cineradiography affected the total DAP values. The calibration of kVp and the timer have contributed in the dose reduction. The estimated average effective doses obtained for each group showed that the neonate doses are 50% less than the dose of one year old age group and this is due to the low exposure factors used for neonates. The five year old age group obtained the highest average effective dose of about 4 Sv. The mA, fluoroscopy time and the dose of patient due to cineradiography contribute to the high average dose of 2,851 cGy-cm2 for PDA occlusion. Although COA dilatation procedure has the shortest average time (16.6 min), the high dose of 1,765 cGy-cm2 is due to the high kVp and mA for fluoroscopy and to the contribution of cine radiography. The five year age group obtains the highest DAP and effective dose. The primary cause of this high dose is the cineradiography dose of one patient and about 60% underwent either PDA or COA interventional procedures. This study shows that PDA and COA are high dose procedures that could approach and exceed the threshold dose for skin deterministic effects and that fluoroscopy time alone cannot be used as an indicator of individual doses because of the contribution of cineradiography. The routine quality control tests of the generator and the X ray machine output measurement

  7. Two cases of chronic radiodermatitis caused by cardiac catheterization

    International Nuclear Information System (INIS)

    Coronary angiography (CAG) and percutaneous transluminal coronary angioplasty (PTCA) associated with fluoroscopy and cineradiography deliver higher radiation doses than any other conventional methods and, as a result, expose patients to ionizing radiation. We herein report two cases of radiodermatitis caused by cardiac catheterization whose irradiation dose could be retrospectively calculated. One sixty-year-old female and one sixty eight-year-old female who had suffered from myocardial infarction and angina pectoris, respectively, developed erythematous plaques on the right submammary area and the lesions were initially diagnosed to be fixed drug eruptions. The lesions of submammary area gradually showed the findings of poikiloderma and finally demonstrated ulceration, however, we could not make an accurate diagnosis at that time, due to our lack of knowledge about these radiologic examinations. The cumulative irradiation dose of these cases was calculated to be 58.5 Gy and 45.5 Gy, respectively, and both cases were finally diagnosed to have chronic radiodermatitis as a result of cardiac catheterization. (author)

  8. The role of sphinter of Boyden in bile excretion and its regulating factors

    Institute of Scientific and Technical Information of China (English)

    Jing Guo Wei; Yao Cheng Wang; Qing Jiang Meng

    2000-01-01

    AIM To investigate the role of sphincter of Boyden in bile excretion and its regulating factors.METHODS Perfusion manometry, choledocho-cineradiography, reaction of the sphincter of Boyden toendogenous cholecystokinin (CCK) and immunohistochemical quantitative analysis were performed in 16dogs to study the motility and morphology of the sphincter of Boyden in experimental (postcholecystectomy)group ( n = 8) and the control group (n = 8).RESULTS The bile duct surrounded by SB was a low-pressure lumen (10.0 ± 2.0 mmHg), in which thepressure was significantly different (P<0.01, t = 6. 195) from the basal pressure of the high-pressure area ofsphincter of Oddi (SO), its basal pressure (SOBP) was 16.9±0.5 mmHg. The SB was an enlarged ampulladuring bile excretion interval, and showed active contraction during bile excretion. Intrinsic CCK could causediastole of SO, but does not affect the systole and diastole of SB. After cholecystectomy, spastic contractionpersisted in SB, which could not be relieved by intrinsic CCK. The sensitivity to CCK of SO was decreased,and the evacuation time of media prolonged (27.0±3.4 min vs precholecystectomy 17.l±0.9min P<0.01,t =7.961). In immunohistochemistry analysis, the contents of a-actin, myosin in the SB of experimentalgroup showed no increase. Under electronic microscope, the main changes were 3D structuraldisarrangement of the cell framework, distortion of the microfilaments, swelling and aggregation ofmitochondria at the nuclear side.CONCLUSION The excretion of bile can be divided into two types, physiological bile excretion with a drivemainly caused by the contraction of SB, and the other, functional bile excretion with a drive mainly causedby the contraction of gallbladder. It seems that the function of SB was controlled by vagus, whereas SO wasmore sensitive to the intrinsic CCK, The intact gallbladder is an elemental factor of functional coordinationof SB and SO.

  9. Patient Dose Values during Interventional Cardiology Examinations in Yazd Hospitals, Iran

    Directory of Open Access Journals (Sweden)

    Verginia Tsapaki

    2010-05-01

    Full Text Available Background/Objective: The number of interventional cardiology (IC procedures has increased rapidly. Coronary angiography (CA and percutaneous transluminal coronary angioplasty (PTCA are now widely performed as a matter of routine and they are considered safe procedures for experienced cardiologists. However, it is also known that these procedures are associated with high radiation doses due to long fluoroscopy time (T, and large number of cineradiography frames (F. These levels of radiation may even lead to radiation skin injuries under certain conditions. "nPatients and Methods: A detailed study of radiation doses received by 168 patients who underwent CA, and 84 patients who underwent PTCA using 3 angiography x-ray systems in two hospitals of Yazd-Iran is presented. An air kerma-area product (KAP meter was used for patient dosimetry. KAP, fluoroscopy time and total number cine frames for CA and PTCA procedures were recorded for each patient. "nResults: Mean ± SD of KAP in CA and PTCA were 33 Gy.cm2 ± 18.8 Gy.cm2 and 80.3 Gy.cm2 ± 65.6 Gy.cm2, respectively. The comparison showed that CA KAP (33Gy.cm2, fluoroscopy time (2.7±2.4min, and cine frames number (571±149 except of on case, were lower than (P<0.001 the results of other studies and mean KAP due to PTCA procedures, except for three cases, were not significantly different from the other references' results. "nConclusion: The high-level expert cardiologists could not have a significant effect on the decrease of patient dose since they should also teach angiography examinations to medicine students. With increasing patient BMI the value of KAP increased, but the fluoroscopy time and cine frames number did not change significantly. In addition, the results showed that the use of flat panel detector was not sufficient for decreasing patient dose and the system's adjustment was more important.

  10. Functional MRI of the pharynx in obstructive sleep apnea (OSA) with rapid 2-D flash sequences; Funktionelle MRT des Pharynx bei obstruktiver Schlafapnoe (OSA) mit schnellen 2D-FLASH-Sequenzen

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, L. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Guenther, E. [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Gauger, J. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Nitz, W. [Siemens Medizintechnik, Erlangen (Germany); Kastenbauer, E. [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    1996-03-01

    Functional imaging of the pharynx used to be the domain of cineradiography, CT and ultrafast CT. The development of modern MRI techniques led to new access to functional disorders of the pharynx. The aim of this study was to implement a new MRI technique to examine oropharyngeal obstructive mechanisms in patients with obstructive sleep apnea (OSA). Sixteen patients suffering from OSA and 6 healthy volunteers were examined on a 1.5 T whole-body imager (`Vision`, Siemens, Erlangen Medical Engineering, Germany) using a circular polarized head coil. Imaging was performed with 2D flash sequences in midsagittal and axial planes. Patients and volunteers were asked to breathe normally through the nose and to simulate snoring and the Mueller maneuver during magnetic resonance imaging (MRI). Prior to MRI, all patients underwent an ear, nose and throat (ENT) examination, functional fiberoptic nasopharyngoscopy and polysomnography. A temporal resolution of 6 images/s and an in-plane resolution of 2.67x1.8 mm were achieved. The mobility of the tongue, soft palate and pharyngeal surface could be clearly delineated. The MRI findings correlated well with the clinical examinations. We propose ultrafast MRI as a reliable and non-invasive method of evaluating pharyngeal obstruction and their levels. (orig.) [Deutsch] Die funktionelle Bildgebung des Pharynx war bisher eine Domaene der Hochfrequenzroentgenkinematographie, der Computertomographie (CT) und der ultraschnellen Computertomographie. Die Entwicklung moderner Techniken in der Magnetresonanztomographie (MRT) fuehrte zu neuen Ansaetzen in der Diagnostik pharyngealer Dysfunktionen. Ziel der vorliegenden Studie war die Implementierung neuer schneller MR-Sequenzen, um Verschlussmechanismen entlang des Pharnyxschlauches bei Patienten mit obstruktiver Schlafapnoe (OSA) zu untersuchen. 16 Patienten mit OSA und 6 gesunde Probanden wurden an einem 1,5-T-Ganzkoerpermagnetresonanztomographen (`Vision`, Siemens Medizintechnik, Erlangen