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Sample records for angiographically occult vascular

  1. Clinical presentations and MRI findings of angiographically occult vascular malformations

    International Nuclear Information System (INIS)

    Various clinical features as well as MRI findings of AOVM (angiographically occult vascular malformation) were studied. Amongst out patients, since January 1988, there have been 30 cases of symptomatic AOVM (20 males, 10 females) including 4 cases with multiple lesions. The age ranged from 3 to 60 years of age, with a mean of 33.4 years. The locations of symptomatic lesions were in the cerebral hemisphere (15), the thalamus (4), the brain stem (8) and in the cerebellum (3). The initial presentations of these 30 cases were either by hemorrhage (18), convulsive seizure (9) or by progressive neurological deficits (3). The initial presentation was not related to the patient's age and the size of the lesion, but apparently related to the location of AOVM. Most of the lesions in the cerebral hemisphere presented seizures, but all of the lesions in the thalamus, the brain stem and the cerebellum disclosed hemorrhage as an initial presentation. In fact it was noticed that brain stem lesions tend to cause repetitive hemorrhage in a relatively short period. AOVM lesions were clearly visualized with T2-weighted MRI images, consisting of high intensity cores with surrounding low intensity rims. Most of the symptomatic lesions were partially enhanced by Gd-DTPA with varied intensity. Dynamic changes in size and enhancement pattern on MRI were occasionally seen, usually accompanied with episodes such as hemorrhage or neurological deterioration. Although AOVMs were angiographically negative some strands indicating draining veins were observed on MRI in several cases. In contrast, none of the nonsymptomatic lesions (22 lesions) demonstrated enhancement effects with Gd-DTPA. (author)

  2. Gamma-radiosurgery of angiographically occult vascular malformations

    International Nuclear Information System (INIS)

    Since the installation of Gamma-knife, we have treated 26 cases of AOVM (angiographically occult vascular malformations), who had enough follow-up period more than 12 months. There were 16 males and 10 females, whose ages ranged from 3 to 58 years with an average of 32.7. Their clinical presentations at the onset were hemorrhage in 17, seizure in 7, and progressive neurological deficits in 2. Three cases had multiple lesions of AOVM. Among 26 symptomatic lesions, 15 were located supratentorially, 7 in brain stem and 4 in cerebellar hemisphere. AOVMs were treated with radiosurgery at the marginal doses between 15 to 20 Gy (mean 17.9 Gy). Follow-up studies revealed a rebleeding in one after the treatment in the mean follow-up period of 17.7 months. Among 7 cases presented with seizure, 5 were improved and the other 2 showed no change. Imaging studies with MRI showed a major shrinkage in 1, minor shrinkage in 7, and no obvious change in 18. Symptomatic perifocal edema occurred in 5 (19.2%), especially those who were treated at the marginal dose more than 18 Gy. In conclusion our preliminary clinical results indicate that the radiosurgery with Gamma-knife has positive effects to prevent the rebleeding and to control the seizures associated with symptomatic AOVMs. (author)

  3. Stereotactic radiosurgery in the management of angiographically occult vascular malformations

    International Nuclear Information System (INIS)

    Purpose: To evaluate the role of stereotactic radiosurgery in the treatment of angiographically occult vascular malformations (AOVMs). Methods and Materials: From 1987 to 1996, 21 patients, 10 males and 11 females, median age of 41 years (range: 7-75 years), with an intracerebral AOVM underwent stereotactic radiosurgery at our institution. All were considered at high risk for surgical intervention. The vascular lesions were located in the brainstem (17 patients), basal ganglia (2), occipital lobe (1), and cerebellum (1). Diagnosis was based on high-resolution magnetic resonance imaging (MRI). Clinical presentation at onset included previous intracerebral hemorrhage (20 patients) and epilepsy (1). All patients were treated with a linac-based radiosurgical technique. The median dose delivered was 25 Gy (range 13-50 Gy), typically prescribed to the 80-90% isodose surface (range 50-90%), which corresponded to the periphery of the vascular malformation. Patients were followed by clinical neurologic assessment and by MRI on a regular interval basis. Results: Follow-up was obtained in 20 patients; clinical or MRI information was not available for 1 patient, and this patient was excluded from our analysis. At a median follow-up of 77 months (range: 4-141 months), follow-up MRIs postradiosurgery do not demonstrate any changes in the appearance of the AOVM. Four patients developed an intracranial bleed at 4, 8, 35, and 57 months postradiosurgery. Annual hemorrhage rates were considerably higher in the observation period preradiosurgery than postradiosurgery (30% vs. 3.2%, p<0.001). Complications postradiosurgery were observed in 4 patients. Three patients developed mild to moderate edema surrounding the radiosurgical target, expressed at 5, 8, and 24 months, respectively. In all cases, the edema was transient and resolved completely on subsequent MRIs. One of the 4 patients developed radiation necrosis 8 months after radiosurgery. Conclusion: The use of stereotactic

  4. Occult Mediastinal Great Vessel Trauma: The Value of Aortography Performed During Angiographic Screening for Blunt Cervical Vascular Trauma

    International Nuclear Information System (INIS)

    Purpose. To determine the value of aortography in the assessment of occult aortic and great vessel injuries when routinely performed during screening angiography for blunt cerebrovascular injury (BCVI). Methods. One hundred and one consecutive patients who received both aortography and screening four-vessel angiography over 4 years were identified retrospectively. Angiograms for these patients were evaluated, and the incidence of occult mediastinal vascular injury was determined. Results. Of the 101 patients, 6 (6%) had angiographically documented traumatic aortic injuries. Of these 6 patients, one injury (17%) was unsuspected prior to angiography. Four of the 6 (67%) also had BCVI. One additional patient also had an injury to a branch of the subclavian artery. Conclusion. Routine aortography during screening angiography for BCVI is not warranted due to the low incidence (1%) of occult mediastinal arterial injury. However, in the setting of a BCVI screening study and no CT scan of the chest, aortography may be advantageous

  5. Angiographically occult arteriovenous malformations causing intracerebral hemorrhage

    International Nuclear Information System (INIS)

    We had experienced 5 cases of angiographically occult AVMs led to intracerebral hemorrhage and progressive neurologic deficit and seizure. Cerebral angiography in each case failed to demonstrate the vascular nature of the lesion and conventional skull radiography was no use. Computed tomography (CT), in 4 cases out of 5, showed well demarcated, slightly hyperdense and ovoid masses which turned out resolving hematomas. These lesions had also contained focal areas of high densities. In one case we observed definitively enhanced area in the resolving hematoma and it was corresponded to histopathologically proved AVM. CT appearance of acute hemorrhage at the subcortical region of cerebral hemisphere was showed in another case. We believe that CT can afford important supplementary information regarding an associated hematoma for angiographically occult AVM. Caution is advised in assuming that angiographically avascular lesion demonstrable by CT is not vascular malformation.

  6. Angiographically occult vascular malformation of the brain: MR imaging at 1.5 T

    International Nuclear Information System (INIS)

    MR imaging was performed in nine patients with 12 angiographically occult arteriovenous malformations using a 1.5-T superconducting magnet; four additional patients were imaged using a 0.3-T system. All images were reviewed in conjunction with CT scans. The following observations were made. (1) Eleven of 14 supratentorial lesions were located at the junction of gray and white matter. (2) Exclusing acute hemorrhage, only two lesions displayed mild mass effect. (3) All lesions displayed central foci of high signal intensity, probably representing subacute hemorrhage. (4) All lesions but one showed a peripheral rim of low signal intensity which progressively lost signal with increasing T2 weighting. This most likely represents iron-containing hemosiderin deposition. (5) Lesions were best demonstrated with long repetition times and moderate T2 weighting (TR = 2,500 msec, TE = 25-100 msec). (6) All lesions but one were hyperdense on non-contrast-enhanced CT, although only three had unequivocal calcification. The possibility of hyperdensity due to blood or iron deposition is discussed

  7. Vascular parameters from angiographic images

    International Nuclear Information System (INIS)

    This paper measures geometric and dynamic vascular parameters using digital angiographic image sequences: An image analysis system for neuroangiography is being developed by the Medical Imaging Division and Endovascular Therapy section of our department. Angiographic images are obtained from a GE Digital Fluoricon 5000 system. The image sets are analyzed on a Stellar GS2000 graphics mini-supercomputer using software modules written for use with the Application Visualization System (AVS). Flow phantoms are used to evaluate analysis routines and bolus injection techniques

  8. Angiographically occult angiomas: a report of thirteen cases with analysis of the cases documented in the literature.

    Science.gov (United States)

    Wakai, S; Ueda, Y; Inoh, S; Nagai, M

    1985-10-01

    Thirteen cases of angiographically occult angioma (AOA) are reported. Nine of these presented with intraparenchymatous hemorrhage, and the other 4 patients had epilepsy. The pathological diagnosis was arteriovenous malformation in 12 cases and cavernous angioma in 1. All surgical specimens but 2 contained hemosiderin pigment. In addition to these 13 cases, we reviewed 159 cases of AOA reported in the literature and analyzed them in terms of age, sex, symptoms and signs at admission, computed tomographic findings, location and size of angioma, history of previous and recurrent hemorrhage, type of hemorrhage, and outcome of operation to determine the characteristics of AOAs. The results of these analyses are described in detail, and the indications for surgical treatment of suspected AOAs are discussed. Our microsurgical technique for detecting the angioma within or adjacent to the hematoma is also presented. PMID:4058688

  9. Endoscopic ultrasound guided thrombin injection of angiographically occult pancreatitis associated visceral artery pseudoaneurysms: Case series

    OpenAIRE

    Gamanagatti, Shivanand; Thingujam, Usha; Garg, Pramod; Nongthombam, Surajkumar; Dash, Nihar Ranjan

    2015-01-01

    Pseudoaneurysm is a known complication of pancreatitis associated with significant mortality and morbidity. Imaging plays an important role in the diagnosis and management. Computed tomography (CT) helps localize the lesion and the severity of the background pancreatitis but digital subtraction angiography with coil embolization is recommended to avoid bleeding and inadvertent surgery. However, in cases where angiographic coil embolization is not feasible due to technical reasons, thrombin in...

  10. MR imaging assessment of cerebral vascular disease: A combination of angiographic and parenchymal techniques

    International Nuclear Information System (INIS)

    This study tested the accuracy and clinical utility of a three-dimensional MR angiographic technique of the cervical carotids in combination with a routine spin-echo examination of the brain as a screening examination for cerebrovascular disease in 23 patients. The technique used a fast low-angle shot sequence with a reduced echo time and voxel size, gradient refocusing, and time of flight effects to minimize signal loss secondary to phase dispersion and maximize vessel contrast. Subsequent multiplanar three-dimensional reconstructions were obtained at 50 increments about the z-axis via ray-tracing linear thresholding algorithms. Examinations were compared with IV/IA-digital subtraction angiography or Doppler US as the objective of accuracy. Results of this ongoing study indicate that an MR angiographic screening examination can be coupled with routine brain MR imaging with only a 10-14 minute extension of examination time, providing both a vascular and a parenchymal evaluation

  11. A case of angiographically occult, distal small anterior inferior cerebellar artery aneurysm

    OpenAIRE

    Hisashi Kubota; Yasuhiro Sanada; Kazuhiro Nagatsuka; Amami Kato

    2015-01-01

    Background: A small aneurysm at an unusual location, such as a distal anterior inferior cerebellar artery (AICA) aneurysm, may conceal as a computed tomography angiography (CTA) and digital subtraction angiography (DSA)-occult aneurysm. Case Description: We herein present the case of a patient suffering from a subarachnoid hemorrhage (SAH) with two aneurysms in which the AICA aneurysm was negative by CTA and DSA. CTA demonstrated a right anterior choroidal artery aneurysm, which was revea...

  12. Endoscopic ultrasound guided thrombin injection of angiographically occult pancreatitis associated visceral artery pseudoaneurysms:Case series

    Institute of Scientific and Technical Information of China (English)

    Shivanand; Gamanagatti; Usha; Thingujam; Pramod; Garg; Surajkumar; Nongthombam; Nihar; Ranjan; Dash

    2015-01-01

    Pseudoaneurysm is a known complication of pancreatitis associated with significant mortality and morbidity. Imaging plays an important role in the diagnosis and management. Computed tomography(CT) helps localize the lesion and the severity of the background pancreatitis but digital subtraction angiography with coil embolization is recommended to avoid bleeding and inadvertent surgery. However, in cases where angiographic coil embolization is not feasible due to technical reasons, thrombin injection via CT or ultrasound guidance remains a viable option and often described in literature. In this series, effort has been made to highlight the role of endoscopic ultrasound guided thrombin instillation especially in patients with poorly visualized pseudoaneurysm on ultrasound thereby avoiding surgery and the associated mortality and morbidity.

  13. Patterns of vascular invasion of intrahepatic peripheral cholangiocarcinoma examined with angiography and angiographic CT

    International Nuclear Information System (INIS)

    To evaluate the radiological patterns of vascular invasion in peripheral cholangiocarcinomas. Hepatic arteriography and portography in 20 cases with cholangiocarcinoma including 12 cases with angiographic CT were retrospectively analyzed. The arteriography showed no arterioportal shunt, hypertrophy of tumor vessel, or tumor staining extending to central portion of the mass in all cases. However, doughnut shaped peripheral tumor staining was seen until late hepatogram phase in 12 cases and compensatory hyperperfusion around the mass was seen in six cases (eight cases if include arterial CT). Encasement of tumor vessel was seen in 12 cases, and hypertrophy of feeding vessel in nine cases. On portography, the filling defect on segmental portal branch could be demonstrated only in 11 cases. Shape of the portal defect was tapered narrowing in six cases, abrupt narrowing in two cases but intraluminal nodular filling defect was not seen. Remaining three cases were difficult to define the shape. On seven cases of CT during arterial portography, three cases showed mass shaped defect and four showed segmental defect but three of them could demonstrate the partially preserved portal flow in defective portal area. Hepatic arteriography in peripheral cholagiocarcinoma showed no evidence of hypertrophy of tumor vessels and tumor stain extending to central portion but peripheral staining on late hepatogram phase and compensatory hyperperfusion could be seen. Portal vein was more commonly involved through perivascular connective tissue invasion rather than by direct extension into the portal lumen

  14. Patterns of vascular invasion of intrahepatic peripheral cholangiocarcinoma examined with angiography and angiographic CT

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jae Chun; Cho, Hyun Cheol; Park, Won Kyu [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    1995-01-15

    To evaluate the radiological patterns of vascular invasion in peripheral cholangiocarcinomas. Hepatic arteriography and portography in 20 cases with cholangiocarcinoma including 12 cases with angiographic CT were retrospectively analyzed. The arteriography showed no arterioportal shunt, hypertrophy of tumor vessel, or tumor staining extending to central portion of the mass in all cases. However, doughnut shaped peripheral tumor staining was seen until late hepatogram phase in 12 cases and compensatory hyperperfusion around the mass was seen in six cases (eight cases if include arterial CT). Encasement of tumor vessel was seen in 12 cases, and hypertrophy of feeding vessel in nine cases. On portography, the filling defect on segmental portal branch could be demonstrated only in 11 cases. Shape of the portal defect was tapered narrowing in six cases, abrupt narrowing in two cases but intraluminal nodular filling defect was not seen. Remaining three cases were difficult to define the shape. On seven cases of CT during arterial portography, three cases showed mass shaped defect and four showed segmental defect but three of them could demonstrate the partially preserved portal flow in defective portal area. Hepatic arteriography in peripheral cholagiocarcinoma showed no evidence of hypertrophy of tumor vessels and tumor stain extending to central portion but peripheral staining on late hepatogram phase and compensatory hyperperfusion could be seen. Portal vein was more commonly involved through perivascular connective tissue invasion rather than by direct extension into the portal lumen.

  15. Influence of the gender on cerebral vascular diameters observed during the magnetic resonance angiographic examination of willis circle

    Directory of Open Access Journals (Sweden)

    Marco Antonio Stefani

    2013-02-01

    Full Text Available The present study evaluated the calibers and anatomic configurations based on the Magnetic Resonance analysis (MRA, assaying the cerebral vascular territories and sex-linked variations. A randomized sample of 30 angiographic examinations in adult patients of both sexes was obtained and components of the circle of Willis were identified. Branch diameters were measured on a transversal cut 5mm from the vessel origin in a typical angiographic frontal incidence. For the comparative statistical analysis, tests were divided in the groups considering the patients' sex and age. The classical Circle of Willis configuration was oberved in only 15 samples (50%. Greater calibers were observed in the arteries of the posterior circulation and multiple linear regression analysis established that the caliber of the posterior circulation was influenced by an independent variable related to the gender. Additional variations included unilateral and bilateral fetal and hypoplasic Posterior communicating arteries. In the anterior cerebral artery (ACA, the presence of an accessory developed ACA, an ACA giving branches to the distal portion of the two hemispheres and a third median ACA the variants were observed. Gender influenced the variations on internal diameters of posterior circulation vessels, with larger measurements in men.

  16. Vascular and avascular retinae in mammals. A funduscopic and fluorescein angiographic study.

    Science.gov (United States)

    Buttery, R G; Haight, J R; Bell, K

    1990-01-01

    Intraretinal blood vessels are present in some and absent in other vertebrate species, including the mammals. Among the marsupials, both vascular and avascular retinae are seen. We determined the funduscopic appearance of the eye, investigated the functional aspects of ocular blood flow in both types of retina in marsupials and compared our results with known patterns in placental mammals. The Australian polyprotodont marsupials, the Tasmanian devil, Sarcophilus harrisii, and the quoll, Dasyurus viverrinus, together with an American polyprotodont, the Virginia opossum, Didelphis virginiana, demonstrate variable degrees of tapetal differentiation, pigmentation and a very close parallel course of their intraretinal arteries and veins over considerable distances. Using the technique of fluorescein angiography, we found that retinal blood flow in the 3 vascular Australian species commenced with arterial filling. Early venous was seen next, followed by the capillary blush. This unusual sequence of vascular flow differs from that of the arterial-capillary-venous filling seen in placental mammals. This difference is most likely a consequence of the known looped, end artery organisation found within marsupial nervous systems, of which the retinae are a part. The 2 diprotodont marsupials examined, the brushtail possum, Trichosurus vulpecula, and the sugar glider, Petaurus breviceps, possess avascular retinae. Only a small residual tuft of fluorescein-impermeable vessels projects from the optic disc into the vitreous. Interestingly, the structural complexity of the central visual system in diprotodonts all of whom possess avascular retinae) is commonly accepted as being greater than that of the stem polyprotodont line (which possess vascular retinae). If retinal function matches this internal complexity, then retinal avascularity may, as in birds, be associated with superior vision. However, as the retinae of these mammals clearly lack any nutritive mechanisms directly

  17. MR Angiographic-Guided Percutaneous Sclerotherapy for Venous Vascular Malformations: A Radiation Dose-Reduction Strategy.

    Science.gov (United States)

    Imbesi, S G; Green, D A; Cho, A; Pakbaz, R S

    2016-02-01

    We present a new technique using MRA instead of the usual DSA to provide guidance in the treatment of venous vascular malformations. When one performs this embolization procedure, appropriate needle positioning within the malformation must be confirmed before injection of the sclerosing agent to prevent untoward complications. Time-resolved imaging of contrast kinetics-MRA can accurately depict the angioarchitecture of the lesion, which substantially reduces the total radiation dose in these patients who are commonly in the pediatric age group and usually require numerous treatment episodes. PMID:26338922

  18. Magnetic resonance angiographic assessment of upper extremity vessels prior to vascular access surgery: feasibility and accuracy

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    Planken, Nils R. [Maastricht University Hospital, Department of Vascular Surgery, Maastricht (Netherlands); Maastricht University Hospital, Department of Radiology, Maastricht (Netherlands); Maastricht University Medical School, Cardiovascular Research Institute Maastricht, Maastricht (Netherlands); Tordoir, Jan H. [Maastricht University Hospital, Department of Vascular Surgery, Maastricht (Netherlands); Maastricht University Medical School, Cardiovascular Research Institute Maastricht, Maastricht (Netherlands); Duijm, Lucien E.; Bosch, Harrie C. van den [Catharina Hospital, Department of Radiology, Eindhoven (Netherlands); Sande, Frank M. van der; Kooman, Jeroen P. [Maastricht University Hospital, Department of Nephrology, Maastricht (Netherlands); Maastricht University Medical School, Cardiovascular Research Institute Maastricht, Maastricht (Netherlands); Haan, Michiel W. de; Leiner, Tim [Maastricht University Hospital, Department of Radiology, Maastricht (Netherlands); Maastricht University Medical School, Cardiovascular Research Institute Maastricht, Maastricht (Netherlands)

    2008-01-15

    A contrast-enhanced magnetic resonance angiography (CE-MRA) protocol for selective imaging of the entire upper extremity arterial and venous tree in a single exam has been developed. Twenty-five end-stage renal disease (ESRD) patients underwent CE-MRA and duplex ultrasonography (DUS) of the upper extremity prior to hemodialysis vascular access creation. Accuracy of CE-MRA arterial and venous diameter measurements were compared with DUS and intraoperative (IO) diameter measurements, the standard of reference. Upper extremity vasculature depiction was feasible with CE-MRA. CE-MRA forearm and upper arm arterial diameters were 2.94 {+-} 0.67 mm and 4.05 {+-} 0.84 mm, respectively. DUS arterial diameters were 2.80 {+-} 0.48 mm and 4.38 {+-} 1.24 mm; IO diameters were 3.00 {+-} 0.35 mm and 3.55 {+-} 0.51 mm. Forearm arterial diameters were accurately determined with both techniques. Both techniques overestimated upper arm arterial diameters significantly. Venous diameters were accurately determined with CE-MRA but not with DUS (forearm: CE-MRA: 2.64 {+-} 0.61 mm; DUS: 2.50 {+-} 0.44 mm, and IO: 3.40 {+-} 0.22 mm; upper arm: CE-MRA: 4.09 {+-} 0.71 mm; DUS: 3.02 {+-} 1.65 mm, and IO: 4.30 {+-} 0.78 mm). CE-MRA enables selective imaging of upper extremity vasculature in patients requiring hemodialysis access. Forearm arterial diameters can be assessed accurately by CE-MRA. Both CE-MRA and DUS slightly overestimate upper arm arterial diameters. In comparison to DUS, CE-MRA enables a more accurate determination of upper extremity venous diameters. (orig.)

  19. Occult CSF flow disturbance of patients with Alzheimer type dementia and vascular dementia

    International Nuclear Information System (INIS)

    We report results of Iotrolan CT-cisternography on 41 demented patients (13 males and 28 females) to find 'occult normal pressure hydrocephalus'. These patients were suspected to have CSF flow disturbance from clinical symptoms and simple brain CT scan findings. Their average age, duration of dementia, and score of Hasegawa's dementia scale (HDS) were 76.2 years, 5.9 years, 9.5/32.5,respectively. Before performing CT-cisternography, clinical diagnosis for their dementia were vascular dementia in 18 patients. Alzheimer type dementia in 12, suspect of NPH in 5, and other diagnoses in 6. From the results of cisternography, we found 13 patients with CSF flow disturbance (contrast material remained in the ventricle more than 48 hours after injection), and 17 patients with normal CSF flow. The former showed lower scores of HDS, higher urinary incontinence scores and smaller areas of the interhemispheric fissure on CT scan than the latter. But the former showed no significant difference from the latter in the average age, duration of dementia and width of the ventricles. (author)

  20. Vascular changes in sporadic ergotism. Epidemiology, pathogenesis, clinical practice, and diagnosis with special regard to angiographic documentation

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    Hagen, B.

    1986-08-01

    Whereas the epidemic form of ergotism has been rare in the 20th century, the sporadic form has a wide distribution as a consequence of therapy with ergot-derivative drugs. Favourable prognosis of the condition, with complete recovery from the ischemic peripheral circulatory disorders can be obtained by early diagnosis. Precise evaluation of the history, with recognition of treatment of migraine headache or postpartum hemorraghe with ergot alkaloids, can be determinative in diagnosis. The specific pattern of the angiographic findings, as we saw it in 6 cases within the last 4 years, decisively confirms the diagnosis. We could demonstrate thread-, thorn- and hour glass-like narrowing of the vessels, due to spasm. Total occlusion with the development of collaterals may occur, but we saw no thrombus formation. The stenotic arterial segments had smooth margins. The distribution of the involved arteries was more focal than generalized and more peripheral than central. In two cases spasm could be abolished immediately by a pharmaceutical (i.a. injection of tolazoline) or by anesthetic procedures (halothane). The phenomenologic data, together with the complete reversal of the circulatory ischemic disorders after therapy (particularly the absolute ban of ergots), is so specific that other diseases of ischemic nature (emboli, arteriosclerosis, Buerger's disease, fibromuscular hyperplasia) can be excluded.

  1. Occult CSF flow disturbance of patients with Alzheimer type dementia and vascular dementia; Results from Iotrolan CT-cisternography

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Kazuhiko; Sugita, Yasuko; Funaki, Chiaki (Nagoya Univ. (Japan). Faculty of Medicine) (and others)

    1994-04-01

    We report results of Iotrolan CT-cisternography on 41 demented patients (13 males and 28 females) to find 'occult normal pressure hydrocephalus'. These patients were suspected to have CSF flow disturbance from clinical symptoms and simple brain CT scan findings. Their average age, duration of dementia, and score of Hasegawa's dementia scale (HDS) were 76.2 years, 5.9 years, 9.5/32.5,respectively. Before performing CT-cisternography, clinical diagnosis for their dementia were vascular dementia in 18 patients. Alzheimer type dementia in 12, suspect of NPH in 5, and other diagnoses in 6. From the results of cisternography, we found 13 patients with CSF flow disturbance (contrast material remained in the ventricle more than 48 hours after injection), and 17 patients with normal CSF flow. The former showed lower scores of HDS, higher urinary incontinence scores and smaller areas of the interhemispheric fissure on CT scan than the latter. But the former showed no significant difference from the latter in the average age, duration of dementia and width of the ventricles. (author).

  2. Occult cerebral vascular malformation: High-field (2.0 T) MR imaging and comparison with CT

    International Nuclear Information System (INIS)

    Extensive experience with CT has led to the recognition of criteria for the diagnosis of occult cerebral vascular malformation. MR demonstrated all lesions as hemorrhage foci. The most common and typical MR findings of OVCM was circumscribed thick hypointense rim on T2-weighted images (T2-Wls) representing hemosiderin deposit with various central intensities suggesting the presence of hematomas in different stages (11 lesions). Among these. the recurrent hemorrhage in small amount produced the characteristic 'a bunch of grape' appearance. But, small OCVM less than 1 cm in diameter was identified as a small homogeneous hypointense nodule on T2-Wls with sharp (6 lesions) or fade-out (1 lesions) border. There were 2 lesions showing atypical findings such as dense hemosiderin rin with central lacuma or bilobed subacute hematoma. As the associated MR findings which strongly suggest the diagnosis of OCVM signal void due to feeding or draining vessels was found in 4, lesions and the surrounding focal cortical atrophy or leukomalacia in 2 lesions. The predilection site of OCVM was subcortical (8 lesions) and periventricular (6 cases) location. CT depicted 16 of the 20 lesions, but missed 4 lesions of small OCVM. CT alone did not permit definitive diagnosis of OCVM is most cases. Fifteen lesions demonstrated on CT contained somewhat hyperdense area in central or peripheral locations. Peripheral hyperdense area corresponded to the dense hemosiderin deposit on MR and central one to the hematoma formed by recent hemorrhage. Low density area on CT usually corresponded to liquefied subacute hematoma on MR

  3. Spontaneous intravascular platelet aggregation in angiographic studies

    International Nuclear Information System (INIS)

    The process of intravascular platelet aggregation is activated in angiographic clinical studies using 76% Verografin solution. It has been shown in experiments op rats that verografin (2 ml/kg) and iodamide (2 ml/ kg) together with the activation of intravascular platelet aggregation inhibit antiaggregation properties of the vascular wall

  4. Angiographic diagnosis and differentiation of pancreatic tumours

    International Nuclear Information System (INIS)

    In an 8-year period (1971-1978) 92 patients were examined because of suspected pancreatic tumour and the following symptoms were found: in 13 cases (14.1%) inoperable pancreatic carcinoma, in 2 cases insuloma, in 5 patients pancreatic cyst, in 5 cases pancreatitis, in one patient pancreatic abscess and in 12 cases alterations in the environing organs. The observed angiographic symptoms are described in detail. Except the richly vascularized tumour grown together with the stomach all pancreatic carcinomas were poor in vessels and they caused tumourous invasions in the greater arteries. The obliteration of the lienal vein, as well as the development of mesenteric venous collateral circulation signify an inoperable stage. The signs of the differential diagnosis of the pancreatitis and the carcinoma are dealt with in detail. In case of secondary pancreatic tumours - not even detectable by post-mortem examination - the angiographic signs are to be taken into consideration. (author)

  5. CT, MR and angiographic findings of hemangiopericytomas

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    Lim, Soo Mee; Lee, Ho Kyu; Shin, Ji Hoon; Kim, Jae Kyun; Kim, Dae Hong; Choi, Choong Gon; Suh, Dae Chul [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-07-01

    Hemangiopericytoma(HP) exhibits its pathologic findings different from those of meningioma or other angiomatous tumor; and its clinical behavior is unique and prognosis worse than other cases. We reviewed the CT, MR and angiographic findings of HPs and evaluated differential radiologic points of comparison between typical meningiomas and meningeal HPs. MR(n=16), CT(n=5) and angiographic imaging(n=10) were performed in 18 patients(M:F = 12:6, mean age: 45 years) with histologically proven primary HPs. We evaluated the imaging findings of HPs with respect to site, shape, size, signal intensity, enhancement characteristics, vascular signal voids, calcification, bony and adjacent sinus involvement, and angiographic findings. HPs were meningeal in 14 cases and nonmeningeal in four. Meningeal HPs were located in the parasagittal region(n=8), convexity(n=3), intradural extramedullary space(n=1), choroid plexus(n=1), and olfactory groove(n=1). Nonmeningeal HPs were located in the masticator space(n=2), paraspinal area(n=1) and supraclavicular area(n=1). The mean maximal dimension of tumors was about 5.4cm and their shape was papillary(n=8) or lobulated(n=7). MR images showed high(n=13) or iso(n=3) signal intensities on T2W1, and heterogeneity on T2W1(n=9). Vascular signal voids in the mass were seen in all cases, while in two cases, CT scanning showed nodular dense calcification. Bone destruction was present in six cases, but no hyperostosis was found. In five cases, the superior sagittal sinus was involved. Angiographic images revealed highly vascular masses supplied by the internal carotid artery(n=5), external carotid artery(n=8), descending scapular artery(n=1) and radiculomedullary artery(n=1), with delayed tumor blush during the capillary and venous phase in which there was no arteriovenous shunt. HP is one of the extra-axial tumors in which there is hypervascularity, aggressive bony destruction arising in the meningeal and extrameningeal area, and heterogeneous high

  6. CT, MR and angiographic findings of hemangiopericytomas

    International Nuclear Information System (INIS)

    Hemangiopericytoma(HP) exhibits its pathologic findings different from those of meningioma or other angiomatous tumor; and its clinical behavior is unique and prognosis worse than other cases. We reviewed the CT, MR and angiographic findings of HPs and evaluated differential radiologic points of comparison between typical meningiomas and meningeal HPs. MR(n=16), CT(n=5) and angiographic imaging(n=10) were performed in 18 patients(M:F = 12:6, mean age: 45 years) with histologically proven primary HPs. We evaluated the imaging findings of HPs with respect to site, shape, size, signal intensity, enhancement characteristics, vascular signal voids, calcification, bony and adjacent sinus involvement, and angiographic findings. HPs were meningeal in 14 cases and nonmeningeal in four. Meningeal HPs were located in the parasagittal region(n=8), convexity(n=3), intradural extramedullary space(n=1), choroid plexus(n=1), and olfactory groove(n=1). Nonmeningeal HPs were located in the masticator space(n=2), paraspinal area(n=1) and supraclavicular area(n=1). The mean maximal dimension of tumors was about 5.4cm and their shape was papillary(n=8) or lobulated(n=7). MR images showed high(n=13) or iso(n=3) signal intensities on T2W1, and heterogeneity on T2W1(n=9). Vascular signal voids in the mass were seen in all cases, while in two cases, CT scanning showed nodular dense calcification. Bone destruction was present in six cases, but no hyperostosis was found. In five cases, the superior sagittal sinus was involved. Angiographic images revealed highly vascular masses supplied by the internal carotid artery(n=5), external carotid artery(n=8), descending scapular artery(n=1) and radiculomedullary artery(n=1), with delayed tumor blush during the capillary and venous phase in which there was no arteriovenous shunt. HP is one of the extra-axial tumors in which there is hypervascularity, aggressive bony destruction arising in the meningeal and extrameningeal area, and heterogeneous high

  7. Accessory left gastric artery: angiographic anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Soo; Lim, Hyung Guhn; Kim, Hong Soo; Jeon, Doo Sung [Presbyterian Medical Center, Chunju (Korea, Republic of); Chung, Jin Wook; Park, Jae Hyung [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of); Song, Soon Young [Myongji Hospital, College of Medicine, Kwandong University, Seoul (Korea, Republic of)

    2000-09-01

    To evaluate the angiographic anatomy of the accessory left gastric artery (accLGA). We evaluated the angiographic findings of the accLGA in 50 patients (Angiostar; Siemens, Erlangen, Germany). Performing celiac and selective angiography in 50 and 34 patients, respectively. By means of celiac angiography, (1) site of origin, (2) anatomical course, (3) diameter, (4) degree of tortuosity, and (5) distal tapering were evaluated, while selective angiography was used to determine (1) arterial branching, (2) area of blood supply, and (3) patterns of gastric wall stain. Celiac angiography showed that the accLGA arose from the left hepatic artery (LHA) in 45 cases (90%) and from the proper hepatic artery in five (10%). If the accLGA arose from the LHA, its origin entirely depended on the branching pattern of the latter. It always arose from the lateral branch of the LHA furthest to the left and uppermost, and proximal to its umbilical point. The most common anatomical course of the accLGA, seen in 27 cases (54%), was between the S2 and S3 segmental branch. The diameter and degree of tortuosity of the accLGA were similar to those of adjacent intrahepatic branches in 21 (42%) and 33 cases (66%), respectively. The degree of tapering was less than that of adjacent intrahepatic vessel in 28 (56%). Selective angiography demonstrated esophageal branching of the acc LGA in 27 cases (79%), inferior phrenic arterial branching in three (9%), a mediastinal branch in one (3%), and hypervascularity of the lung in one (3%). In 15 cases (44%), bifurcation of the accLGA was recognized. The vascular territory of the accLGA was the gastric fundus together with the distal esophagus in 21 cases (62%), mainly the gastric fundus in six (18%), and mainly the distal esophagus in four (12%). The pattern of gastric mucosal stain was curvilinear wall in 31 cases (91%) and nodular in three (9%). A knowledge of the angiographic anatomy of the accLGA facilitates accurate recognition of this artery on

  8. Liver Transplant Rejection: Angiographic Findings in 35 Patients

    OpenAIRE

    White, Robert M.; Zajko, Albert B.; Demetris, A Jake; Bron, Klaus M.; DEKKER, ANDREW; Starzl, Thomas E.

    1987-01-01

    Rejection, the leading cause of liver allograft dysfunction, is usually detected by liver biopsy. The purpose of this study was to determine if there are angiographic findings that correlate with this posttransplantation complication. In a retrospective study, the angiograms of 35 patients with histologically proven allograft rejection were reviewed. The examinations were done because of suspected posttransplantation vascular complications. Abnormal hepatic arteriograms were observed in 30 (8...

  9. Hepatic metastasis from choriocarcinoma: angiographic findings in two cases

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yun Jung; Oh, Joo Hyeong; Yoon, Yup; Kim, Eui Jong; Kim, Deog Yoon; Kang, Heung Sun [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2002-12-01

    We report two cases of hepatic metastases from choriocarcinoma in women of childbearing age in whom imaging studies performed at presentation revealed the presence of liver masses, and who had clinically progressive anemia or intraabdominal hemorrhage. CT demonstrated heterogeneously enhanced liver masses. Characteristic angiographic findings included hypervascular hepatic masses with aneurysmal dilatations of the peripheral hepatic arteries at the arterial phase and persistent vascular lakes at the venous phase.

  10. Radiation dose during angiographic procedures

    International Nuclear Information System (INIS)

    The use of angiographic procedures is becoming more prevalent as new techniques and equipment are developed. There have been concerns in the scientific community about the level of radiation doses received by patients, and indirectly by staff, during some of these radiological procedures. The purpose of this study was to assess the level of radiation dose from angiographic procedures to patient at the Ottawa Hospital, General Campus. Radiation dose measurements, using Thermo-Luminescent Dosimeters (TLDs), were performed on more than 100 patients on various procedures. The results show that while the patient dose from the great majority of angiographic procedures is less than 2 Gy, a significant number of procedures, especially interventional procedures may have doses greater than 2 Gy and may lead to deterministic effects. (author)

  11. Angiographic technique in rabbits: an experimental study

    International Nuclear Information System (INIS)

    Objective: The rabbit is the most important experimental animal for the basic interventional research, which has displayed the essential value for the interventional experimental diagnosis and therapy in some tumor and vascular disease, while the angiography is the basic imaging examination for the related study. This research attempts to improve and to optimize the angiographic technique for the experimental rabbits, as well as to modify the hemostasis course in order to increase the success rate of angiographic study in rabbits. At the same time. a preliminary study of CTA and DSA in rabbits has also been made in order to get the relative experience. Methods: Fifteen New Zealand white rabbits were anesthetized, which was followed by CTA with the contrast injection through the ear vein catheterization. The diameters of the major blood vessels were measured and their shape and course were observed. An 18 G needle was used to puncture the blood vessels and a 4 F single bend catheter to perform the DSA examination. The groin area was dissected, the femoral artery and femoral vein were separated, and the catheter was inserted with Seldinger technique. For angiography examination, after the femoral artery was successfully punctured, DSA of the aortic arch, dorsal aorta, abdominal aorta, iliac artery, carotid artery, vertebral artery, celiac artery, anterior mesenteric artery and renal artery was carried out in proper sequence and the appearance of pertaining veins were also observed. For venography examination, after the femoral vein was successfully punctured, angiography of the posterior vena cava and pulmonary artery was performed successively. The femoral vein was pressed for a few minutes to stop bleeding, while the femoral artery bleeding was stanched by forceps, local wet compression with thrombin or surgical reconstruction of femoral artery sheath. Results: According to the diameter and shape of the major vessels, the combination of 18 G vascular puncture

  12. The Occult Today: Why?

    Science.gov (United States)

    Kessler, Gary E.

    1975-01-01

    Author offered some reflections on the "why" of the contemporary interest in the occult. He attempted to convince the reader that, if he or she has been surprised by the recent rise of occultism, sober reflection will dispell some fears and, perhaps, even convince him or her that occultism is not merely superstition. (Author/RK)

  13. Digital vascular imaging (DVI)

    International Nuclear Information System (INIS)

    Digitization of the video signals from an image intensifier/TV chain, followed by subtraction, contrast enchancement and reconversion to analogue signals, enables high quality angiographic images to be obtained from an intravenous injection of contrast medium. As the examination is basically noninvasive it can be used in outpatients. The possibilities of Digital Vascular Imaging are demonstrated by images obtained from the various vascular regions using a triple-mode 14 in. image intensifier with a Plumbicon. TV tube. (Auth.)

  14. Deep shadow occulter

    Science.gov (United States)

    Cash, Webster (Inventor)

    2010-01-01

    Methods and apparatus are disclosed for occulting light. The occulter shape suppresses diffraction at any given size or angle and is practical to build because it can be made binary to avoid scatter. Binary structures may be fully opaque or fully transmitting at specific points. The diffraction suppression is spectrally broad so that it may be used with incoherent white light. An occulter may also include substantially opaque inner portion and an at least partially transparent outer portion. Such occulters may be used on the ground to create a deep shadow in a short distance, or may be used in space to suppress starlight and reveal exoplanets.

  15. Angiographic features of 26 children with Takayasu's arteritis

    International Nuclear Information System (INIS)

    Background: Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease affecting primarily the aorta, its proximal branches and the pulmonary arteries Objectives: To retrospectively review the angiograms of children with TA so as to describe the patterns of vascular involvement. Patients and methods: Twenty-six children with TA who differed from most other studies in that almost all of them presented with hypertension, reflecting the incidence of abdominal aortic and renal artery involvement. Results: The most consistent finding was stenosis of the aorta. Marginal irregularity/undulation of the aorta was also a useful angiographic diagnostic feature in subtle disease. The incidence of aneurysms was high compared to other studies and both fusiform and saccular aneurysms were encountered. Percutaneous transluminal angioplasty (PTA) was successful in all eight patients in whom it was performed. MRI, CT angiography and US are discussed as less invasive imaging alternatives. TA is a significant cause of renovascular hypertension in children in South Africa where there is a high incidence of tuberculous infection. Knowledge of the angiographic features and pattern of aortic involvement is essential for diagnosis and initiation of early and appropriate treatment, including PTA. (orig.)

  16. Is Occult Obscure Gastrointestinal Bleeding a Definite Indication for Capsule Endoscopy? A Retrospective Analysis of Diagnostic Yield in Patients with Occult versus Overt Bleeding

    Directory of Open Access Journals (Sweden)

    Ikue Watari

    2013-01-01

    Full Text Available Background/Aim. Usefulness of capsule endoscopy (CE for diagnosing small-bowel lesions in patients with obscure gastrointestinal bleeding (OGIB has been reported. Most reports have addressed the clinical features of overt OGIB, with few addressing occult OGIB. We aimed to clarify whether occult OGIB is a definite indication for CE. Methods. We retrospectively compared the cases of 102 patients with occult OGIB and 325 patients with overt OGIB, all having undergone CE. The diagnostic yield of CE and identification of various lesion types were determined in cases of occult OGIB versus overt OGIB. Results. There was no significant difference in diagnostic yield between occult and overt OGIB. The small-bowel lesions in cases of occult OGIB were diagnosed as ulcer/erosive lesions (n=18, 18%, vascular lesions (n=11, 11%, and tumors (n=4, 3%, and those in cases of overt OGIB were diagnosed as ulcer/erosive lesions (n=51, 16%, vascular lesions (n=31, 10%, and tumors (n=20, 6%. Conclusion. CE detection rates and CE identification of various small-bowel diseases do not differ between patients with occult versus overt OGIB. CE should be actively performed for patients with either occult or overt OGIB.

  17. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease

    DEFF Research Database (Denmark)

    Onuma, Yoshinobu; Dudek, Dariusz; Thuesen, Leif; Webster, Mark; Nieman, Koen; Garcia-Garcia, Hector M; Ormiston, John A; Serruys, Patrick W

    2013-01-01

    This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California).......This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California)....

  18. ANGIOGRAPHIC ASPECTS OF MYOCARDIAL BRIDGES

    Directory of Open Access Journals (Sweden)

    Sujatha. M

    2015-12-01

    with high angiographic incidence of myocardial bridges (MB's, when compared with other population in India. We observed more lengthy bridges which may cause luminal reduction of coronary vessel and myocardial ischemia (MI, we also observed higher incidence of MB’s in male patients but systolic luminal reduction is more in female patients then in males. These observations suggest that the risk of MI will be more for the female patients with MB’s.

  19. Insertion of central venous catheters for hemodialysis using angiographic techniques in patients with previous multiple catheterizations

    Energy Technology Data Exchange (ETDEWEB)

    Kotsikoris, Ioannis, E-mail: gkotsikoris@gmail.com [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece); Zygomalas, Apollon, E-mail: azygomalas@upatras.gr [Department of General Surgery, University Hospital of Patras (Greece); Papas, Theofanis, E-mail: pfanis@otenet.gr [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece); Maras, Dimitris, E-mail: dimmaras@gmail.com [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece); Pavlidis, Polyvios, E-mail: polpavlidis@yahoo.gr [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece); Andrikopoulou, Maria, E-mail: madric@gmail.com [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece); Tsanis, Antonis, E-mail: atsanis@gmail.com [Department of Interventional Radiology, “Erythros Stauros” General Hospital (Greece); Alivizatos, Vasileios, E-mail: valiviz@hol.gr [Department of General Surgery and Artificial Nutrition Unit, “Agios Andreas” General Hospital of Patras (Greece); Bessias, Nikolaos, E-mail: bessias@otenet.gr [Department of Vascular Surgery, “Erythros Stauros” General Hospital (Greece)

    2012-09-15

    Introduction: Central venous catheter placement is an effective alternative vascular access for dialysis in patients with chronic renal failure. The purpose of this study was to evaluate the insertion of central venous catheters for hemodialysis using angiographic techniques in patients with previous multiple catheterizations in terms of efficacy of the procedure and early complications. Materials and methods: Between 2008 and 2010, the vascular access team of our hospital placed 409 central venous catheters in patients with chronic renal failure. The procedure was performed using the Seldinger blind technique. In 18 (4.4%) cases it was impossible to advance the guidewire, and so the patients were transported to the angiography suite. Results: Using the angiographic technique, the guidewire was advanced in order to position the central venous catheter. The latter was inserted into the subclavian vein in 12 (66.6%) cases, into the internal jugular vein in 4 (22.2%) and into the femoral vein in 2 (11.1%) cases. There was only one complicated case with severe arrhythmia in 1 (5.5%) patient. Conclusion: Our results suggest that insertion of central venous catheters using angiographic techniques in hemodialysis patients with previous multiple catheterizations is a safe and effective procedure with few complications and high success rates.

  20. The occult abscess

    International Nuclear Information System (INIS)

    The clinical signs of an abscess may be masked by the patient's immunosuppressed state or antibiotic therapy. The authors reviewed the clinical presentations of 30 patients with 32 occult abscesses diagnosed with CT or US over 4 years. The abscesses included 12 intraperitoneal, 16 retroperitoneal, and four pleural infected fluid collections. Initial symptoms included fever of unknown origin in six patients and musculoskeletal complaints in four. Six patients were diagnosed with noninflammatory medical problems, five were under investigation for tumor, and, while an infectious process was suspected in nine patients, an associated abscess was not. The occult abscess may mimic other disease processes, and the radiological may be the first to suggest the diagnosis in patients in whom the classic signs and symptoms are absent

  1. GAMBARAN RADIOLOGIS PADA OCCULT PNEUMOTHORAKS

    OpenAIRE

    Putu Aditha Satya Putra; Nyoman Srie Laksminingsih

    2013-01-01

    Pneumothorax is a recognized cause of death in chest wall trauma. Radiological examination is the key factor to establish the existence of a pneumothorax. Occult pneumothorax is pneumothorax that undiagnosed clinically and with thoracic x-ray, but it can be tolerated while other more urgent trauma. Occult pneumothorax can be detected by CT (Computed tomography). Occult pneumothorax may progress to tension pneumothorax in certain circumstances. Missing in diagnosed pneumothorax will cause deat...

  2. Arteriographic evaluation, in the perispheric vascular trauma

    International Nuclear Information System (INIS)

    136 patients were angiographically studied under the suspicion of perispheric vascular lesion submitted to the radiology department of the San Vicente de Paul University Hospital (H.U.S.VP.) Medellin Colombia. The majority of the patients were young with wounds caused by gunshots (79.4%). the must frequent angiographic indication was the proximity of the wound to a vascular path (44.5%). 63% of the patients with angiography indicative of abnormality needed surgery from which 21% were because of the proximity of the wound to a vascular path and 76% because of the mayor findings when admitted to the hospital. the possible complications as a result of the angiographic procedure were revised only find inc two mayor reactions to the contrast media. there were no late complications. Angiography is highlighting sensitive (100%) specific (98.5%) and secure in the evaluation of patients with perispheric vascular trauma. Due to the high number of false negatives when the physical examination is performed, every patient with a wound near a vascular path must be evaluated angiographically

  3. Coronary arterial Disease associated with arteriosclerosis in lower extremity: Angiographic analysis

    International Nuclear Information System (INIS)

    We performed both peripheral and coronary angiographies in 52 patients with an arteriosclerosis in lower extremities. The severity of arteriosclerotic narrowing of the coronary and peripheral arteries were compared on angiographies. An angiographic vascular score(AVS, 0-5) reflecting the number and the degree of stenosis in 12 lower extremity arteries and three major coronary arteries was assigned to each angiogram and the sun of scores in the lower extremity arteries was compared with the incidence of significant coronary artery disease (more than grade 3) and coronary score. Relation of incidence and severity of vascular stenosis and risk factors (diabetes metallitus, hypertension, smoking, and hypercholesterolemia) was also analyzed. Thirty-four of 52 patients (65%) had an angiographically significant coronary artery disease. Thirteen of these 34 patients (38%) had no clinical symptom and sign of the ischemic heart disease. There was no statistically significant difference in the incidence and severity of coronary artery disease between high (more than 30) and low AVS group in lower extremity (p>0.14). All patients had at least one risk factor and 49 of 52 patients (94%) had multiple risk factors. Coronary angiography was normal in there patients with only one risk factors, and angiographically significant coronary artery disease existed in nine of 16 cases (56.3%) with two risk factors. 13 of 17 case (76.5%) with three risk factors, and 12 of 16 cases (75.0%) with all four risk factors. There were no significant correlations between individual risk factors and incidence, severity of arteriosclerosis in coronary and lower extremity arteries. In conclusion, angiographic evaluation of the coronary artery disease in patients with lower extremity arteriosclerosis is necessary because of the high chance of coronary artery disease and difficulty in the prediction of coronary artery disease with a severity of the peripheral arteriosclerosis, presence of various risk

  4. DIFFERENT CLINICAL AND ANGIOGRAPHIC FINDING IN A SET OF IRANIAN IDENTICAL TWIN: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Mohammad Shojaie

    2013-01-01

    Full Text Available Both genetic and environmental causes are involved in developing of Coronary Artery Disease (CAD, but there is a notable controversy about the environmental and genetic factors that play a role in the pathogenesis of CAD. The value of each individual risk factor on CAD and the incidence of coronary artery disease in identical twins are indefinite. To find out genetic mechanisms of coronary heart disease, the assessment of twins study may help us. On the other hand the natural history of coronary artery disease in an asymptomatic twin with a symptomatic counterpart is undistinguishable. We present a case report about different coronary angiographic findings on an Iranian identical Lady Twin with different clinical outcome in access to incidence of CAD in twins. Based on our patient and the information on other patients, the asymptomatic twins of symptomatic counterparts need aggressive assessment and management for occult coronary artery disease.

  5. Angiographic findings of gastrointestinal stromal tumor

    Institute of Scientific and Technical Information of China (English)

    Song-Hua Fang; Dan-Jun Dong; Shi-Zheng Zhang; Mei Jin

    2004-01-01

    AIM: To discuss the angiographic features of gastrointestinal stromal tumor (GIST) and to evaluate their diagnostic role.METHODS:Twelve patients with pathologically proved GIST underwent angiography (DSA)1 wk before operation,using Puck and digital subtraction DSA.The origin,size,morphology and angiographic appearance of the lesions were reviewed.RESULTS:Two tumors arose from stomach,8 from jejunum,and 2 from ileum.Seven cases were benign and 5 were malignant.Obviously thickened supplying arteries were detected in 8 tumors,and early-developed veins were found in 3.Two types of angiographic changes of GIST were observed.Four cases had twisted irregular neoplastic vessels with partially coarse and indistinct margins,which were all malignant.Eight cases had ball-like neoplastic vessels with uniform tumor staining,of which 7 were benign and 1 was malignant.CONCLUSION:Angiography facilitates localization and diagnosis of GIST,helps define their size,range and location,and is especially valuable to patients suffering from melena with unknown reasons.

  6. The Halogen Occultation Experiment

    Science.gov (United States)

    Russell, James M., III; Gordley, Larry L.; Park, Jae H.; Drayson, S. R.; Hesketh, W. D.; Cicerone, Ralph J.; Tuck, Adrian F.; Frederick, John E.; Harries, John E.; Crutzen, Paul J.

    1993-01-01

    The Halogen Occultation Experiment (HALOE) uses solar occultation to measure vertical profiles of O3, HCl, HF, CH4, H2O, NO, NO2, aerosol extinction, and temperature versus pressure with an instantaneous vertical field of view of 1.6 km at the earth limb. Latitudinal coverage is from 80 deg S to 80 deg N over the course of 1 year and includes extensive observations of the Antarctic region during spring. The altitude range of the measurements extends from about 15 km to about 60-130 km, depending on channel. Experiment operations have been essentially flawless, and all performance criteria either meet or exceed specifications. Internal data consistency checks, comparisons with correlative measurements, and qualitative comparisons with 1985 atmospheric trace molecule spectroscopy (ATMOS) results are in good agreement. Examples of pressure versus latitude cross sections and a global orthographic projection for the September 21 to October 15, 1992, period show the utility of CH4, HF, and H2O as tracers, the occurrence of dehydration in the Antarctic lower stratosphere, the presence of the water vapor hygropause in the tropics, evidence of Antarctic air in the tropics, the influence of Hadley tropical upwelling, and the first global distribution of HCl, HF, and NO throughout the stratosphere. Nitric oxide measurements extend through the lower thermosphere.

  7. CT angiographic evaluation of perforators in the lower limb and their reconstructive implication

    Directory of Open Access Journals (Sweden)

    Visweswar Bhattacharya

    2012-01-01

    Full Text Available Background: The perforator flaps evolved on the knowledge of the vascular tree from the main vascular trunk up to the subdermal plexus. Therefore, we thought that it′s necessary to map the whole vascular arcade by CT angiography. The aim of this study is to evaluate the perforators and the whole vascular tree of the lower limb by peripheral CT angiography with 3D reconstruction and intraoperative evaluation. This study helps in designing flaps of different constituents based on the selected perforators. Materials and Methods: Twenty patients having lower limb defects were selected. CT angiography was done using a non-ionic iodinated contrast media injected through the antecubital vein. The lower limbs were imaged using volume rendering CT scan machine. Three dimensional reconstructions were made. The whole arterial tree, along with the perforators, were mapped. Findings of the audio-Doppler were correlated with the CT angiographic observations. Further these evaluations were confirmed by intraoperative findings. Results: The three dimensional CT angiographic reconstruction with bone and soft tissue provided advanced knowledge of this vascular network. It delineated the main vessel, the perforators, their caliber, distance from fixed bony landmarks and course up to the subdermal plexus. These findings were confirmed during dissection of the proposed flap. The perforators were mainly musculocutaneous in the proximal leg and septocutaneous distally. Conclusions: The vascular details visualized by this technique made advancement over the existing methods namely color Doppler, audio Doppler, two dimensional angiography etc. It improved the understanding of perforator flaps and their successful clinical application.

  8. Feasibility and Safety of Transradial Arterial Approach for Simultaneous Right and Left Vertebral Artery Angiographic Studies and Stenting

    International Nuclear Information System (INIS)

    Objectives. This study investigated whether the transradial artery (TRA) approach using a 6-French (F) Kimny guiding catheter for right vertebral artery (VA) angiographic study and stenting is safe and effective for patients with significant VA stenosis. Background. The TRA approach is commonly performed worldwide for both diagnostic cardiac catheterization and catheter-based coronary intervention. However, to our knowledge, the safety and feasibility of left and right VA angiographic study and stenting, in the same procedure, using the TRA approach for patients with brain ischemia have not been reported. Methods. The study included 24 consecutive patients (22 male, 2 female; age, 63-78 years). Indications for VA angiographic study and stenting were (1) prior stroke or symptoms related to vertebrobasilar ischemia and (2) an asymptomatic but vertebral angiographic finding of severe stenosis (>70%). A combination of the ipsilateral and retrograde-engagement technique, which involved a looping 6-F Kimny guiding catheter, was utilized for VA angiographic study. For VA stenting, an ipsilateral TRA approach with either a Kimny guiding catheter or a left internal mammary artery guiding catheter was utilized in 22 patients and retrograde-engagement technique in 2 patients. Results. A technically successful procedure was achieved in all patients, including left VA stenting in 15 patients and right VA stenting in 9 patients. The mean time for stenting (from engagement to stent deployment) was 12.7 min. There were no vascular complications or mortality. However, one patient suffered from a transient ischemic attack that resolved within 3 h. Conclusion. We conclude that TRA access for both VA angiographic study and VA stenting is safe and effective, and provides a simple and useful clinical tool for patients unsuited for femoral arterial access

  9. 21 CFR 892.1600 - Angiographic x-ray system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1600 Angiographic x-ray system....

  10. The Occult: Diabolica to Alchemists

    Science.gov (United States)

    Delaney, Oliver J.

    1971-01-01

    The 91 items in this bibliography deal with works of occult science. The material is subdivided into biographies, dictionaries, encyclopedias, handbooks, noteworthy histories, indices, annuals, and a few miscellany works with treatises. (95 references) (Author)

  11. Characterization of vascular tree architecture using the Tokunaga taxonomy

    Science.gov (United States)

    Galarreta-Valverde, Miguel A.; Zoghbi, Jihan M.; Pereira, Fabricio; Beregi, Jean-Paul; Mekkaoui, Choukri; Jackowski, Marcel P.

    2015-03-01

    The diagnosis of cardiovascular disease is usually assisted by resonance angiography (MRA) or computed tomography angiography (CTA) imaging. The identification of abnormal vascular architecture from angiographic three-dimensional images is therefore crucial to the diagnosis of cardiovascular disease. Automated detection and quantification of vascular structure and architecture thus holds significant clinical value. In this work, we employ a Lindenmayer system to represent vascular trees from angiographic images and describe a quantitative measure based on the Tokunaga taxonomy to differentiate vascular architectures. Synthetic vessel architectures with varying bifurcation patterns were compared and results showed that this architectural measure is proportional to the level of branching. In real MRA images, this measure was able to differentiate between normal and abnormal intracerebral vasculature containing an aneurysm. Hence, this methodology not only allows for compact representation of vascular architectures but also provides a quantitative metric of bifurcation complexity, which has the potential to characterize different types of vascular abnormalities.

  12. The relationship between the angiographic findings and the clinical features of carotid artery plaque.

    Science.gov (United States)

    Kim, D I; Lee, S J; Lee, B B; Kim, Y I; Chung, C S; Seo, D W; Lee, K H; Ko, Y H; Kim, D K; Do, Y S; Byun, H S

    2000-01-01

    The purpose of this study was to investigate the histological characteristics of atheromatous carotid plaque, and to analyze the relationship between the angiographic findings and the clinical features. We retrospectively reviewed 55 cases of carotid endarterectomy for extracranial internal carotid artery stenosis, who were treated at our institute from January 1995 to December 1997. The histological examination included hematoxylin-eosin staining, Masson-trichrome staining, and immunostaining for antismooth muscle antibody and anti-CD68 antibody. The main compositions of the carotid plaque included synthetic type vascular smooth muscle cells and extracellular matrix. The histological findings showed ulceration in 49 (89.1%) cases, calcium deposits in 42 (76.4%) cases, and an inflammatory reaction in 44 (80.0%) cases. Neurological abnormalities were strongly associated with plaque ulceration (P = 0.045) and an inflammatory reaction (P = 0.013), whereas no correlation existed regarding calcium deposits (P = 0.173). The angiographic findings showed ulceration in 46 (83.6%) cases. Plaque ulceration in the angiography findings showed no statistically significant correlation with the histologic findings (P = 0.410) and preoperative neurologic abnormalities (P = 0.059). All of the atherosclerotic risk factors such as hypertension, smoking, diabetes mellitus, hyperlipidemia, and myocardial infarction had no statistically significant correlation with the histological features of the carotid plaque. In conclusion, the main compositions of carotid plaque were synthetic-type vascular smooth muscle cells and extracellular matrix. The histological ulceration and inflammatory reaction of the plaque showed a statistically significant correlation with the preoperative neurologic symptoms, whereas no correlation was seen in the calcium deposits. Angiographic ulceration showed no correlation with the histological findings or preoperative neurologic abnormalities. In addition, the

  13. The IMACS Occultation Survey

    Science.gov (United States)

    Payne, Matthew John; Holman, Matthew; Alcock, Charles; Osip, David; Schlichting, Hilke

    2015-11-01

    We report the results of our extended campaign to search for occultations of background stars by small (sub-km) Kuiper belt objects (KBOs) using the IMACS instrument on the Magellan Telescope.We implemented a novel shutterless continuous readout mode on the IMACS instrument, with custom-made aperture masks, permitting simultaneous high-speed (~40 Hz) photometry for numerous stars, while minimizing the effects of stellar crowding and sky background. Observing in the southern hemisphere allows us to target the intersection of the ecliptic and galactic planes, where hundreds of stars can be monitored with a single field of view.We observed for a total of ~28 hours spread over eight nights, obtaining over 10,000 star-hours of light curves with per-point SNR > 10. This represents an order of magnitude increase in star hours compared to the previous best ground-based survey by Bianco et al. (2009). Our results allow us to place strong constraints on the surface density of sub-km objects in the Kuiper-Belt, as well as to complement the HST FGS results of Schlichting et al. (2009, 2012).

  14. Do radiologists control angiographic and interventional procedures

    International Nuclear Information System (INIS)

    Academic institutions nationwide were surveyed to determine the degree to which radiologists control 13 angiographic or interventional procedures that are potential turf battles. The data reveal that academic radiologists retain virtually complete control of peripheral angioplasty, renal angioplasty, percutaneous biliary drainage, and CT- or US-guided abscess drainage. They largely dominate percutaneous nephrostomies, percutaneous ureteral stent placements, and pulmonary angiography. They have somewhat lesser but still important roles in percutaneous gastrostomy and inferior vena cava filter placement. Radiologists control kidney stone lithotripsy in only 7% of institutions but have varying degrees of involvement in another 57%. The performance of coronary angiography, pediatric angiocardiography, and coronary angioplasty is almost totally controlled by cardiologists, although radiologists maintain a significant interpretive role

  15. Home Use Tests: Fecal Occult Blood

    Science.gov (United States)

    ... Procedures In Vitro Diagnostics Home Use Tests Fecal Occult Blood Share Tweet Linkedin Pin it More sharing ... test kit to measure the presence of hidden (occult) blood in your stool (feces). What is fecal ...

  16. Optimization of beam filtering, kV-mA regulation curve, and image intensifier entrance exposure rate to reduce radiation exposure in angiographic fluoroscopy

    International Nuclear Information System (INIS)

    Aim of study: Evaluation of radiation exposure and image quality during fluoroscopy using a new vascular X-ray system. Material and methods: The measurements were made on an Integris V 3000 X-ray system with MRC tube and SpectraBeam technology (Philips Medical Systems, Hamburg). Entrance dose rates were measured with phantoms for the three fluoroscopy levels (1-3) which differed with regard to beam filtering and image intensiver entrance exposure rate. We evaluated 132 diagnostic and interventional angiographic studies. The angiographic investigators were asked to start with level 1 and to change to the next fluoroscopy level only in the case of insufficient image quality. Results: Entrance dose rate is reduced by approx. 74% at fluoroscopy level 1 and by approx. 46% at level 2 relative to level 3 which is comparable to angiographic X-ray systems without MRC tube and SpectraBeam technology. Because level 1 ensured a sufficient image quality in 92% of the diagnostic and 60% of the interventional angiographic procedures a change to higher fluoroscopy levels was not necessary. Conclusion: Reduction of the intensifier exposure rate and the optimization of beam filtering enabled us to reduce the radiation exposure considerably. The procedure was well accepted by the angiographic investigators due to the diagnostically sufficient image quality of the fluoroscopy level 1. (orig.)

  17. Occult Participation: Its Impact on Adolescent Development.

    Science.gov (United States)

    Tennant-Clark, Cynthia M.; And Others

    1989-01-01

    Investigated relationship between occult participation, substance abuse, and level of self-esteem among 25 clinical (alcohol or drug treatment) and 25 nonclinical adolescents. Results indicated that adolescent substance abuse and occult participation were significantly related. Found significant differences between high versus low occult groups…

  18. New Occultation Systems and the 2005 July 11 Charon Occultation

    Science.gov (United States)

    Young, L. A.; French, R. G.; Gregory, B.; Olkin, C. B.; Ruhland, C.; Shoemaker, K.; Young, E. F.

    2005-08-01

    Charon's density is an important input to models of its formation and internal structure. Estimates range from 1.59 to 1.83 g/cm3 (Olkin et al. 2003. Icarus 164, 254), with Charon's radius as the main source of uncertainty. Reported values of Charon's radius from mutual events range from 593±13 (Buie et al. 1992, Icarus 97, 211) to 621±21 km (Young & Binzel 1994, Icarus 108), while an occultation observed from a single site gives a lower limit on the radius of 601.5 km (Walker 1980 MNRAS 192, 47; Elliot & Young 1991, Icarus 89, 244). On 2005 July 11 UT (following this abstract submission date), Charon is predicted to occult the star C313.2. If successful, this event will be the first Charon occultation observed since 1980, and the first giving multiple chords across Charon's disk. This event is expected to measure Charon's radius to 1 km. Our team is observing from three telescopes in Chile, the 4.0-m Blanco and the 0.9-m telescopes at Cerro Tololo and the 4.2-m SOAR telescope at Cerro Pachon. At SOAR, we will be using the camera from our new PHOT systems (Portable High-speed Occultation Telescopes). The PHOT camera is a Princeton Instrument MicroMAX:512BFT from Roper Scientific, a 512×512 frame-transfer CCD with a readnoise of only 3 electrons at the 100 kHz digitization rate. The camera's exposures are triggered by a custom built, compact, stand-alone GPS-based pulse-train generator. A PHOT camera and pulse-train generator were used to observe the occultation of 2MASS 1275723153 by Pluto on 2005 June 15 UT from Sommers-Bausch Observatory in Boulder Colorado; preliminary analysis shows this was at best a grazing occultation from this site and a successful engineering run for the July 11 Charon occultation. The work was supported, in part, by NSF AST-0321338 (EFY) and NASA NNG-05GF05G (LAY).

  19. Fluorescein angiographic findings and clinical features in Fuchs' uveitis.

    Science.gov (United States)

    Bouchenaki, Nadia; Herbort, Carl P

    2010-10-01

    Fuchs' uveitis is very often diagnosed with substantial delay, which is at the origin of deleterious effects such as unnecessary treatment and its consequences. The aim of this study was to analyse the type and frequency of posterior inflammatory and fluorescein angiographic signs in Fuchs' uveitis in conjunction with other clinical signs. Patients seen at the Centre for Ophthalmic Specialised Care (COS) in Lausanne and the Memorial A. de Rothschild, Clinique Générale-Beaulieu in Geneva between 1995 and 2008 with the diagnosis of Fuchs' uveitis and who had undergone a fundus fluorescein angiography (FFA) were analysed. In addition to FFA signs, the data collected included age, gender, initial and final visual acuities, clinical findings at presentation, mean diagnostic delay and ocular complications. Between 1995 and 2008, 105 patients seen in our centres in Lausanne and Geneva were diagnosed with Fuchs' uveitis. Forty of them (38.1%) had undergone at least one FFA. One patient was excluded because of a concomittant diagnosis of multiple sclerosis. In 28 of 39 patients (71.2%) diagnosis was not reached at presentation with a mean diagnosis delay of 3.67 ± 4.86 years (range: 1 month-24 years). The original erroneous diagnosis was intermediate uveitis in 16 patients (57.1%), posterior uveitis in two patients (7.1%), panuveitis in four patients (14.3%) and anterior granulomatous uveitis in six patients (21.4%). Fluorescein angiography demonstrated the presence of disc hyperfluorescence in 43/44 eyes (97.7%), sectorial peripheral retinal vascular leaking in 6/44 eyes (13.6%) and cystoid macular oedema in 4/44 eyes (9.1%), all of which were seen in eyes having undergone cataract surgery. Fuchs' uveitis was bilateral in 5/39 patients (12.8%). The most frequent clinical signs were vitritis in 42/44 eyes (95.5%), stellate keratic precipitates in 41 eyes (93.2%), posterior subcapsular opacities or cataract in 19 eyes (43.2%), and heterochromia in 19 eyes (43.2%). Fuchs

  20. Wavelet-based calculation of cerebral angiographic data from time-resolved CT perfusion acquisitions

    Energy Technology Data Exchange (ETDEWEB)

    Havla, Lukas; Dietrich, Olaf [Ludwig-Maximilians-University Hospital Munich, Josef-Lissner-Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Munich (Germany); Thierfelder, Kolja M.; Beyer, Sebastian E.; Sommer, Wieland H. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany)

    2015-08-15

    To evaluate a new approach for reconstructing angiographic images by application of wavelet transforms on CT perfusion data. Fifteen consecutive patients with suspected stroke were examined with a multi-detector CT acquiring 32 dynamic phases (∇t = 1.5s) of 99 slices (total slab thickness 99mm) at 80kV/200mAs. Thirty-five mL of iomeprol-350 was injected (flow rate = 4.5mL/s). Angiographic datasets were calculated after initial rigid-body motion correction using (a) temporally filtered maximum intensity projections (tMIP) and (b) the wavelet transform (Paul wavelet, order 1) of each voxel time course. The maximum of the wavelet-power-spectrum was defined as the angiographic signal intensity. The contrast-to-noise ratio (CNR) of 18 different vessel segments was quantified and two blinded readers rated the images qualitatively using 5pt Likert scales. The CNR for the wavelet angiography (501.8 ± 433.0) was significantly higher than for the tMIP approach (55.7 ± 29.7, Wilcoxon test p < 0.00001). Image quality was rated to be significantly higher (p < 0.001) for the wavelet angiography with median scores of 4/4 (reader 1/reader 2) than the tMIP (scores of 3/3). The proposed calculation approach for angiography data using temporal wavelet transforms of intracranial CT perfusion datasets provides higher vascular contrast and intrinsic removal of non-enhancing structures such as bone. (orig.)

  1. Wavelet-based calculation of cerebral angiographic data from time-resolved CT perfusion acquisitions

    International Nuclear Information System (INIS)

    To evaluate a new approach for reconstructing angiographic images by application of wavelet transforms on CT perfusion data. Fifteen consecutive patients with suspected stroke were examined with a multi-detector CT acquiring 32 dynamic phases (∇t = 1.5s) of 99 slices (total slab thickness 99mm) at 80kV/200mAs. Thirty-five mL of iomeprol-350 was injected (flow rate = 4.5mL/s). Angiographic datasets were calculated after initial rigid-body motion correction using (a) temporally filtered maximum intensity projections (tMIP) and (b) the wavelet transform (Paul wavelet, order 1) of each voxel time course. The maximum of the wavelet-power-spectrum was defined as the angiographic signal intensity. The contrast-to-noise ratio (CNR) of 18 different vessel segments was quantified and two blinded readers rated the images qualitatively using 5pt Likert scales. The CNR for the wavelet angiography (501.8 ± 433.0) was significantly higher than for the tMIP approach (55.7 ± 29.7, Wilcoxon test p < 0.00001). Image quality was rated to be significantly higher (p < 0.001) for the wavelet angiography with median scores of 4/4 (reader 1/reader 2) than the tMIP (scores of 3/3). The proposed calculation approach for angiography data using temporal wavelet transforms of intracranial CT perfusion datasets provides higher vascular contrast and intrinsic removal of non-enhancing structures such as bone. (orig.)

  2. MR imaging of occult fractures

    International Nuclear Information System (INIS)

    Objective: To investigate the value of MR imaging in detecting occult fractures. Methods: Sixteen cases with acute trauma were studied using radiography and MR imaging, three cases also underwent CT examinations. Three fractures occurred in the femur condyle, 8 in the proximal tibia and 5 in the thoracolumbar spine. Results: All sixteen cases had normal radiographic results. In 11 cases with femur condyle and tibia occult fracture, MR imaging demonstrated linear low signal in the subcortical region in 3 cases and irregular low signal from articular faces to shaft in 8 cases on both T1WI and T2WI, and high signal changes around low signal were seen on T2WI, and the width of low signal was less than 4 mm on both T1WI and T2WI. The high signal in T1 weighted-Fat saturated sequence was more remarkable and wider than that on T2WI. 3 cases with CT scanning showed no fracture signs. In five cases with thoracolumbar vertebral occult fractures, MR imaging demonstrated horizontal linear low signal in the center of vertebra on both T1WI and T2WI, and high signal changes around low signal were seen on T2WI. Conclusions: MR imaging could early determine the diagnosis of occult fractures. MRI should be the next examination of choice when plain films fail to reveal suspected fractures in the setting of suggestive symptoms and positive physical examination

  3. Angiographic Findings In Patients With Cerebral Aneurysm

    Directory of Open Access Journals (Sweden)

    Miri S M

    2004-09-01

    Full Text Available Background: This investigation was conducted in order to study angiographic findings in patients with cerebral aneurysm. Materials and Methods: The study conducted on 136 cases of ruptured cerebral aneurysms between 1995-2000 confirmed by means of 4-vessel cerebral angiography to get an insight to racial, geographic and environmental factors predisposing to the occurrence of subarachnoid hemorrhage and aneurysm formation. Results: The data analysis revealed the following results: 58% of the population comprised of male and 42% female with a mean age of 46 years. 89% of the aneurysms were found in the anterior circulation and 11% occurred in the posterior cerebral circulation. The most common site in both the sexes was the anterior communicating artery. 9.6% of the patients displayed two separate aneurysms. 5.2% of the aneurysms were found to be giant aneurysms and 3% of the patients had fusiform aneurysms. Conclusion: The low average age, a predilection in male population and the prevalence of aneurysms at carotid and middle cerebral artery bifurcation and the distal branches of anterior cerebral artery and a higher incidence of anterior communicating artery in women were the findings observed in this study.

  4. Probabilistic fusion of angiographic and echographic images for the 3D reconstruction of vessels

    Science.gov (United States)

    Pellot-Barakat, Claire J. M.; Bloch, Isabelle; Sureda, Francisco; Herment, Alain; Sigelle, Marc; Horain, Patrick J.; Long, Anne

    1995-05-01

    In order to provide a better quantitative and morphologic description of complex vascular lesions, we propose an approach of 3D reconstruction of the vessel internal wall, based on data fusion from two different imaging sources: two x ray digital angiography projections and a stack of endovascular echography slices. After extraction of echographic and angiographic information to be fused, a geometric model leads to the determination of the unknown parameters which allow the alignment of all data in a common reference frame. Both types of data are then directly included in a probabilistic reconstruction process based on Markov random fields. The Markovian model consists of cost functions reflecting x ray and ultrasonic data consistency and regularization elements to control the anatomic reality of the reconstruction. The optimal solution according to the definition criteria is obtained by minimizing the model energy with an algorithm based on simulated annealing. Preliminary results have been obtained with data acquired on a dog aorta. The accuracy of reconstruction by data fusion is significantly improved compared with results obtained with separate reconstruction from angiographic or echographic data. Taking into account all information available about the problem, the method avoids uncertainties and ambiguities of a reconstruction based only on one modality, and the probabilistic fusion solves the possible contradictions between both acquisitions.

  5. A work atlas of vascular imaging

    International Nuclear Information System (INIS)

    This book is a practical, atlas of technique - ideal as a single source reference for radiologists, radiology residents, and internists and surgeons interested in vascular disease. It aids in the performance and interpretation of peripheral angiography, and of patient care for the procedure. In addition it provides a cross-reference between angiographic findings and disease entities, and helps reader to correlate angiography, DSA, CT, ultrasound and nuclear medicine for the most efficient and productive management of the patient

  6. Vascular malformations of the mandible (intraosseous haemangiomas)

    Energy Technology Data Exchange (ETDEWEB)

    Guibert-Tranier, F.; Piton, J.; Caille, J.M.; Riche, M.C.; Merland, J.J.

    1982-11-01

    Haemangiomas of the mandible are relatively rare arteriovenous malformations: 85 cases have been described since 1849. The severe risk of bleeding during tooth extraction or biopsy led us to describe the radiological and angiographic features of this condition. The afferent vessles are the inferior dental, the lingual and the facial arteries. Preoperative embolization reduces the risk of bleeding at operation. Surgical treatment must assure the complete removal of the lesion. Radiotherapy and vascular ligatures are useless and dangerous.

  7. Vascular malformations of the mandible (intraosseous haemangiomas)

    International Nuclear Information System (INIS)

    Haemangiomas of the mandible are relatively rare arteriovenous malformations: 85 cases have been described since 1849. The severe risk of bleeding during tooth extraction or biopsy led us to describe the radiological and angiographic features of this condition. The afferent vessles are the inferior dental, the lingual and the facial arteries. Preoperative embolization reduces the risk of bleeding at operation. Surgical treatment must assure the complete removal of the lesion. Radiotherapy and vascular ligatures are useless and dangerous. (orig.)

  8. Vascular Cures

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  9. 21 CFR 864.6550 - Occult blood test.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Occult blood test. 864.6550 Section 864.6550 Food... DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6550 Occult blood test. (a) Identification. An occult blood test is a device used to detect occult blood in urine or feces. (Occult blood...

  10. Angiographer's exposure to radiation under different fluoroscopic imaging conditions

    International Nuclear Information System (INIS)

    Scattered radiation levels near an imaging system commonly used in angiography were measured with a 200 mm thick water phantom. The scattered radiation exposure rate was measured in lines parallel in space to the central ray of the x-ray beam, at lateral distances of 30-100 cm. The effects of an x-ray beam limiting device, geometric and electric magnification, and rotation angle of the C-arm were also determined. The results indicated that the highest scattered radiation levels occurred near the surface of the phantom where the x-ray beam enters. In P-A geometry, the highest radiation levels occurred below the angiographer's waist. These areas of the body corresponded to the gonads of the angiographer. It has been suggested that angiographers' exposure rates are higher near the gonads than near the chest. However, lead aprons efficiently protect these areas. When smaller field sizes were limited by a variable x-ray beam limiting device, the volume of irradiated tissue was reduced, and the scattered radiation exposure rate was decreased. Further, when larger magnification factors were chosen for the analogue magnification method, the volume of irradiated tissue was reduced by the automatic x-ray beam limiting device, and the scattered radiation exposure rate was decreased. However, smaller field sizes markedly increased patient exposure by auto brightness control. To mitigate the angiographer's exposure, smaller field sizes with x-ray limiting devices are required. However, a larger field size should be used whenever possible to minimize patient exposure. The angiographer's exposure rate was influenced by the incidence direction of the x-ray beam when the C-arm had been rotated around the phantom. Consequently, the angiographer's exposure rate was maximum when the x-ray tube most closely approached the angiographer and was minimum when the image intensifier most closely approached the angiographer. Therefore, to mitigate the angiographer's exposure, attention needs

  11. Gastroesophageal Variceal Filling and Drainage Pathways: An Angiographic Description of Afferent and Efferent Venous Anatomic Patterns

    Directory of Open Access Journals (Sweden)

    Ron C Gaba

    2015-01-01

    Full Text Available Varices commonly occur in liver cirrhosis patients and are classified as esophageal (EV, gastroesophageal (GEV, or isolated gastric (IGV varices. These vessels may be supplied and drained by several different afferent and efferent pathways. A working knowledge of variceal anatomy is imperative for Interventional Radiologists performing transjugular intrahepatic portosystemic shunt and embolization/obliteration procedures. This pictorial essay characterizes the angiographic anatomy of varices in terms of type and frequency of venous filling and drainage, showing that different varices have distinct vascular anatomy. EVs typically show left gastric vein filling and “uphill” drainage, and GEVs and IGVs exhibit additional posterior/short gastric vein contribution and “downhill” outflow. An understanding of these variceal filling and drainage pathways can facilitate successful portal decompression and embolization/obliteration procedures.

  12. Gastroesophageal Variceal Filling and Drainage Pathways: An Angiographic Description of Afferent and Efferent Venous Anatomic Patterns.

    Science.gov (United States)

    Gaba, Ron C; Couture, Patrick M; Lakhoo, Janesh

    2015-01-01

    Varices commonly occur in liver cirrhosis patients and are classified as esophageal (EV), gastroesophageal (GEV), or isolated gastric (IGV) varices. These vessels may be supplied and drained by several different afferent and efferent pathways. A working knowledge of variceal anatomy is imperative for Interventional Radiologists performing transjugular intrahepatic portosystemic shunt and embolization/obliteration procedures. This pictorial essay characterizes the angiographic anatomy of varices in terms of type and frequency of venous filling and drainage, showing that different varices have distinct vascular anatomy. EVs typically show left gastric vein filling and "uphill" drainage, and GEVs and IGVs exhibit additional posterior/short gastric vein contribution and "downhill" outflow. An understanding of these variceal filling and drainage pathways can facilitate successful portal decompression and embolization/obliteration procedures. PMID:26713177

  13. Radioimmune localization of occult carcinoma

    International Nuclear Information System (INIS)

    Patients with a rising serum carcinoembryonic antigen level and no clinical or roentgenographic evidence of recurrent or metastatic cancer present a treatment dilemma. Eleven such patients, 10 with a previously treated colorectal carcinoma and 1 with a previously treated breast carcinoma, received an injection of the anticarcinoembryonic antigen monoclonal antibody ZCE-025 labeled with the radioisotope indium 111. Nuclear scintigraphy was performed on days 3 and 5 through 7 to detect potential sites of tumor recurrence. The monoclonal antibody scan accurately predicted the presence or absence of occult malignancy in 7 (64%) patients. Second-look laparotomy confirmed the monoclonal antibody scan results in the patients with colorectal cancer, and magnetic resonance imaging confirmed metastatic breast cancer. This study demonstrates that In-ZCE-025 can localize occult carcinoma and may assist the surgeon in facilitating the operative exploration. In-ZCE-025 assisted in the initiation of adjuvant therapy for the patient with breast cancer

  14. Pelvic Arterial Anatomy Relevant to Prostatic Artery Embolisation and Proposal for Angiographic Classification

    International Nuclear Information System (INIS)

    PurposeTo describe and categorize the angiographic findings regarding prostatic vascularization, propose an anatomic classification, and discuss its implications for the PAE procedure.MethodsAngiographic findings from 143 PAE procedures were reviewed retrospectively, and the origin of the inferior vesical artery (IVA) was classified into five subtypes as follows: type I: IVA originating from the anterior division of the internal iliac artery (IIA), from a common trunk with the superior vesical artery (SVA); type II: IVA originating from the anterior division of the IIA, inferior to the SVA origin; type III: IVA originating from the obturator artery; type IV: IVA originating from the internal pudendal artery; and type V: less common origins of the IVA. Incidences were calculated by percentage.ResultsTwo hundred eighty-six pelvic sides (n = 286) were analyzed, and 267 (93.3 %) were classified into I–IV types. Among them, the most common origin was type IV (n = 89, 31.1 %), followed by type I (n = 82, 28.7 %), type III (n = 54, 18.9 %), and type II (n = 42, 14.7 %). Type V anatomy was seen in 16 cases (5.6 %). Double vascularization, defined as two independent prostatic branches in one pelvic side, was seen in 23 cases (8.0 %).ConclusionsDespite the large number of possible anatomical variations of male pelvis, four main patterns corresponded to almost 95 % of the cases. Evaluation of anatomy in a systematic fashion, following a standard classification, will make PAE a faster, safer, and more effective procedure

  15. Pelvic Arterial Anatomy Relevant to Prostatic Artery Embolisation and Proposal for Angiographic Classification

    Energy Technology Data Exchange (ETDEWEB)

    Assis, André Moreira de, E-mail: andre.maa@gmail.com; Moreira, Airton Mota, E-mail: motamoreira@gmail.com; Paula Rodrigues, Vanessa Cristina de, E-mail: vanessapaular@yahoo.com.br [University of Sao Paulo Medical School, Interventional Radiology and Endovascular Surgery Department, Radiology Institute (Brazil); Harward, Sardis Honoria, E-mail: sardis.harward@merit.com [The Dartmouth Center for Health Care Delivery Science (United States); Antunes, Alberto Azoubel, E-mail: antunesuro@uol.com.br; Srougi, Miguel, E-mail: srougi@usp.br [University of Sao Paulo Medical School, Urology Department (Brazil); Carnevale, Francisco Cesar, E-mail: fcarnevale@uol.com.br [University of Sao Paulo Medical School, Interventional Radiology and Endovascular Surgery Department, Radiology Institute (Brazil)

    2015-08-15

    PurposeTo describe and categorize the angiographic findings regarding prostatic vascularization, propose an anatomic classification, and discuss its implications for the PAE procedure.MethodsAngiographic findings from 143 PAE procedures were reviewed retrospectively, and the origin of the inferior vesical artery (IVA) was classified into five subtypes as follows: type I: IVA originating from the anterior division of the internal iliac artery (IIA), from a common trunk with the superior vesical artery (SVA); type II: IVA originating from the anterior division of the IIA, inferior to the SVA origin; type III: IVA originating from the obturator artery; type IV: IVA originating from the internal pudendal artery; and type V: less common origins of the IVA. Incidences were calculated by percentage.ResultsTwo hundred eighty-six pelvic sides (n = 286) were analyzed, and 267 (93.3 %) were classified into I–IV types. Among them, the most common origin was type IV (n = 89, 31.1 %), followed by type I (n = 82, 28.7 %), type III (n = 54, 18.9 %), and type II (n = 42, 14.7 %). Type V anatomy was seen in 16 cases (5.6 %). Double vascularization, defined as two independent prostatic branches in one pelvic side, was seen in 23 cases (8.0 %).ConclusionsDespite the large number of possible anatomical variations of male pelvis, four main patterns corresponded to almost 95 % of the cases. Evaluation of anatomy in a systematic fashion, following a standard classification, will make PAE a faster, safer, and more effective procedure.

  16. The mystery of angiographically silent macular oedema due to taxanes.

    Science.gov (United States)

    Kuznetcova, Tatiana I; Cech, Petr; Herbort, Carl P

    2012-06-01

    Taxanes are widely used anticancer agents, produced from the plants of the genus Taxus (yews). One of the rare side-effects caused by taxanes is a bilateral cystoid macular oedema (CMO). The particularity of this type of CMO is that it is angiographically silent showing no leakage or pooling on fluorescein angiography (FA). To date, the mechanism of this oedema has not been clearly understood and existing theories do not explain this phenomenon very well. Our aim was to report a case of paclitaxel-induced CMO and put forward a putative explanation for this occurrence. A 64-year-old woman presented with a 7-month history of progressively decreasing bilateral visual acuity with an apparently normal fundus. At entry her best-corrected visual acuity (BCVA) was 0.4 for far and near OD and 0.5 for far and near OS. Optical coherence tomography (OCT) revealed a CMO with a central thickness of 561 μm OD and 488 μm OS; there were no signs of intraocular inflammation. FA showed no capillary leakage and quasi absent late hyperfluorescence OU. Indocyanine green angiography was within normal limits. Classical CMO treatment was ineffective and only discontinuation of paclitaxel resulted in recovery of a normal macular structure after 4 weeks with an increase of BCVA to 0.9 OD and 1.0 OS. In order to understand the properties of taxane drug-induced cystoid macular oedema (TDICMO) we compared the spectral OCT findings of our case to an inflammation-induced CMO of equal thickness and to a case of multifocal choroiditis. The plane of separation of TDICMO was above the external limiting membrane in both cases. In contrast to inflammation-induced CMO where the four external bands were well identified, there was attenuation of these bands in TDICMO but no disruption of the layers as seen in multifocal choroiditis, indicating that the fluid in TDICMO had a high viscosity producing a shadow underneath. TDICMO most probably originates from retinal pigment epithelium dysfunction by their

  17. Occult Communications: On Instrumentation, Esotericism, and Epistemology

    OpenAIRE

    Bernard Dionysius Geoghegan

    2015-01-01

    Viewed from the perspective of the occult, formerly straight and narrow conduits of reason may even begin to resemble irregular relays composed of irregular twists and turns. This essay offers a brief overview of key literature on spiritualism and the occult, some larger reflections on the place of the occult within studies of science and communications, and brief summaries of the essays contained in this volume.

  18. Angiographic assessment of renal artery pathology: how reliable

    International Nuclear Information System (INIS)

    The accuracy of the angiographic interpretation of the histologic type of renal artery stenosis was assessed using a renal pathologist's diagnosis as the gold standard. The angiograms of 42 renal artery stenoses were interpreted without other information, except age and gender, independently by six angiographers. This assessment indicated that angiography is not an accurate means by which to distinguish between the individual types of fibromuscular disease of the renal artery. However, it is a fairly accurate means by which to distinguish fibromuscular disease in general from atherosclerosis of the renal artery, 207 (82%) correct interpretations of 252. In addition, in the presence of renal artery stenosis, the absence of abdominal aortic atherosclerosis on angiography is an excellent predictor of fibromuscular renal artery disease, 17 (94%) of 18 specimens. Likewise, in the presence of a renal artery stenosis, angiographically demonstrable abdominal aortic atherosclerosis is a fair predictor of atherosclerotic renal artery disease, 16 (76%) of 21 specimens

  19. Angiographic findings and therapeutic embolization of late hemarthrosis after total joint arthroplasty

    International Nuclear Information System (INIS)

    The objective of this study was to describe the angiographic findings of late spontaneous hemarthrosis after total joint arthroplasty and to illustrate the therapeutic role of angiography. A retrospective multicenter study was performed looking for patients who underwent an angiography for spontaneous hemarthrosis occurring at least 1 month after total joint arthroplasty. Eight patients were included, all suffering from spontaneous hemarthrosis. One patient had an additional large extra-articular hematoma. Angiography in eight cases revealed hypertrophic vascular synovium in seven patients with an additional false aneurysm in one patient. Hypervascularization with pooling of contrast spots was seen in one patient. Five patients underwent selective arterial particulate embolization. Three patients were successfully embolized after one session, one was successful after two sessions, and one patient needed surgery after two embolization sessions. Angiography for late spontaneous hemarthrosis is very effective to exclude or establish vascular malformations and to establish the diagnosis of hypertrophic vascular synovium. Selective arterial embolization seems to be a good therapeutic option as alternative to open or arthroscopic synovectomy. (orig.)

  20. Clinical and Angiographic Factors Associated With Asymptomatic Restenosis After Percutaneous Coronary Intervention

    NARCIS (Netherlands)

    P.N. Ruygrok (Peter); M.W.I. Webster (Mark); V. de Valk (Vincent); G.A. van Es (Gerrit Anne); J.A. Ormiston (John); M-A.M. Morel (Marie-Angèle); P.W.J.C. Serruys (Patrick)

    2001-01-01

    textabstractBACKGROUND: Angiographic restenosis after percutaneous coronary interventional procedures is more common than recurrent angina. Clinical and angiographic factors associated with asymptomatic versus symptomatic restenosis after percutaneous coronary intervention were compared. METHODS AND

  1. Coronary angiographic and scintigraphic findings in experimental cardiac contusion

    International Nuclear Information System (INIS)

    Clinical, angiographic, scintigraphic, and pathologic observations in myocardial contusion were correlated. Radionuclide imaging of the injured heart with /sup 99m/Tc-Sn-polyphosphate provides an accurate diagnosis in acute, even mild, myocardial contusion. The study can be carried out without danger to the critically ill patient. The coronary angiographic findings in this study explain what is occurring pathologically in the heart. Since arteriography is a more invasive technique than radionuclide imaging, its use is recommended only when the image is negative if it is necessary to establish the clinical diagnosis for treatment or when more than one week has elapsed since the injury. (U.S.)

  2. Economic evaluation of angiographic interventions including a whole-radiology in- and outpatient care; Wirtschaftliche Evaluation angiographischer Interventionen einschliesslich einer radiologischen stationaeren und ambulanten Patientenbetreuung

    Energy Technology Data Exchange (ETDEWEB)

    Nolte-Ernsting, C.; Abel, K.; Krupski, G.; Lorenzen, J.; Adam, G. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany)

    2006-01-01

    Purpose: To determine the economic efficiency of a whole-radiology in- and outpatient treatment with angiographic interventions performed as the main or sole therapy. Materials and Methods: The calculations represent the data of a university radiology department, including the following angiographic interventions (neuroradiology not considered): Vascular intervention (PTA, stent implantation) of kidneys and extremities, recanalization of hemodialysis access, chemoembolization, diagnostic arterioportal liver CT, port implantation, varicocele embolization, PTCD, percutaneous implantation of biliary stent. First, the different angiographic interventions are categorized with reference to the German DRG system 2005. Considering the example of a university hospital, the individual cost of each intervention is calculated and correlated with reimbursements by G-DRG2005 and so-called ''ambulant operation'' (EBM200plus). With these data, profits and losses are calculated for both in- and outpatient care. Results: Radiologic interventions of inpatients yield a profit in the majority of cases. With a base rate of 2900 Euro, the profits in our university hospital range between -872 Euro and +3411 Euro (mean: +1348 Euro). On the other hand, those angiographic interventions suitable for ''ambulant operation'' generate average profits of +372 Euro, if only direct costs are considered. The data of outpatient radiological interventions average between 381 Euro up to 1612 Euro lower than compared with profits obtained from in patient care. (orig.)

  3. Convective towers detection using GPS radio occultations

    DEFF Research Database (Denmark)

    Biondi, Riccardo; Neubert, Torsten; Syndergaard, S.;

    an important role since they lead to deep convective activity. With this work we want to investigate if severe storms leave a significant signature in radio occultation profiles in the tropical tropopause layer. The GPS radio occultation (RO) technique is useful for studying severe weather phenomena because...

  4. The Transneptunian Automated Occultation Survey (TAOS II)

    Science.gov (United States)

    Lehner, Matthew J.; Wang, S.; Alcock, C. A.; Cook, K. H.; Furesz, G.; Geary, J. C.; Hiriart, D.; Ho, P. T.; Norton, T.; Reyes-Ruiz, M.; Szentgyorgyi, A.; Yen, W.; Zhang, Z.

    2012-10-01

    The Transneptunian Automated Occultation Survey (TAOS II) will aim to detect occultations of stars by small ( 1 km diameter) objects in the Solar System and beyond. Such events are very rare (field of view and a high speed camera comprising CMOS imagers, the survey will monitor 10,000 stars simultaneously with all three telescopes at a readout cadence of 20 Hz.

  5. Angiographic diagnosis and therapy for radiological interventions in obliterative atherosclerosis of the pelvic and lower limb arteries

    International Nuclear Information System (INIS)

    Angiographic diagnosis and therapy are discussed in relationship to the indications and follow-up of radiological interventions in patients with obliterative atherosclerosis located in the arteries of the pelvis and lower limbs. Various noninvasive diagnostic procedures permit reliable clinical information to be obtained on the localization, extent and geometry of arterial lesions, and the velocity of blood in the vascular system. Determination of symptom-limited ergometry and oscillographic, plethysmographic, Doppler sonographic, light microscopic and magnetic resonance techniques are all described in more detail. The therapeutic interventions are mentioned with regard to angiography and percutaneous transluminal angioplasty (PTA), with particular emphasis on the treatment of risk factors, training, and medication. The long-term results are given after PTA for the Freiburg patient series. Thus, the cooperation of angiologists, radiologists and vascular surgeons considerably optimizes the treatment of patients suffering from occlusive arterial disease. (orig.)

  6. Occultation studies of the solar system

    International Nuclear Information System (INIS)

    Occultations of stars by planets, satellites, planetary ring systems, asteroids, and comets provide valuable opportunities to probe the Solar System in ways otherwise impossible from the surface of the earth. For example, one can precisely measure the size and shape of objects which are much too small to be resolved directly, accurately map the structure and transparency of ring systems, and detect the faintest trace of an atmosphere. In this investigation, researchers identify upcoming occultations through wide-ranging computer searches, provide accurate predictions for the more important events, and observe selected occultations with our specially designed portable photometric equipment. During the past year, researchers produced accurate predictions for an occultation of AG+40 degrees 0783 by 324 Bamberga on 8 December 1987 and coordinated efforts to observe this event. The occultation was successfully observed at 13 sites including two manned by Lowell Observatory astronomers

  7. Occultations for probing atmosphere and climate

    CERN Document Server

    Foelsche, Ulrich; Steiner, Andrea

    2004-01-01

    Use of occultation methodology for observing the Earth's atmosphere and climate has become so broad as to comprise solar, lunar, stellar, navigation and satellite­ crosslink occultation methods. The atmospheric parameters obtained extend from the fundamental variables temperature, density, pressure, water vapor, and ozone via a multitude of trace gas species to particulate species such as aerosols and cloud liquid water. Ionospheric electron density is sensed as well. The methods all share the key properties of self-calibration, high accuracy and vertical resolution, global coverage, and (if using radio signals) all-weather capability. Occultation data are thus of high value in a wide range of fields including climate monitoring and research, atmospheric physics and chemistry, operational meteorology, and other fields such as space weather and planetary science. This wide area of variants and uses of the occultation method has led to a diversi­ fication of the occultation-related scientific community into a...

  8. Cerebral angiographic findings in thromboangiitis obliterans

    Energy Technology Data Exchange (ETDEWEB)

    No, Young J.; Lee, Eun M.; Kim, Jong S. [University of Ulsan, Department of Neurology, Asan Medical Center, Song Pa, PO Pox 145, Seoul (Korea); Lee, Deok H. [University of Ulsan, Department of Neuroradiology, Asan Medical Center, Song Pa, PO Pox 145, Seoul (Korea)

    2005-12-01

    Transient ischemic attacks (TIAs) or ischemic stroke may complicate thromboangiitis obliterans (TAO). However, there has been debate regarding the mechanism of ischemic stroke in TAO. We report the case of a patient with TAO who developed repeated TIAs. An angiogram showed multiple alternative areas of arterial occlusions in the distal segments of both middle cerebral arteries. Extensive collateral vessels around the occluded segment were also observed, which resembled the ''tree root'' or ''corkscrew'' vessels described in the peripheral arteries in TAO. Our patient illustrates that cerebral manifestations of TAO may occur with vascular changes that are identical with those encountered in the limb arteries in TAO. (orig.)

  9. Sociology of religion and the occult revival

    Directory of Open Access Journals (Sweden)

    Lennart Ejerfeldt

    1975-01-01

    Full Text Available The "new" that makes the cults of the occult revival to "new religions" of the Western world, is their recently increased social significance. Historically most of modern occultism is anything but new. From the research and theorizing about the occult revival we have picked up some main themes. The first is the social diffusion of the new occultism. In this field, we find some studies of superstition, especially astrology. These illuminate the differences in social connotation between the consumers of superstition and the followers of institutional religion. Secondly the study of the occult revival has made valuable contributions to the conceptualizing of "cult" and the cultic phenomenon. Thirdly, we will look upon the connection between the occult revival and the counter-culture. The problem of the rise of cults as a symptom of socio-cultural change will be briefly discussed with reference to Bell's thesis of "the disjuntion of culture and social structure". Lastly, we proffer some reflections on the occult revival and the new spiritual trends in the churches, which so sharply contrast with the theology and churchmanship of the sixties.

  10. The occultation of Arcturus in the Vatican

    CERN Document Server

    Sigismondi, Costantino

    2013-01-01

    The dome of Saint Peter's Basilica plays the role of the Moon during a stellar occultation and Arcturus is the target star. This occultation-like phenomenon is useful for introducing to occultation astronomy a class of student up to university level. It can be organized very easily at the convenience of the audience. Techical and didactical aspects are discussed; the video is available at http://www.youtube.com/watch?v=hIfsj7t-u-c and has been realized with an ordinary camcorder.

  11. Phase-Occultation Nulling Coronagraphy

    CERN Document Server

    Lyon, Richard G; Clampin, Mark; Petrone, Peter

    2015-01-01

    The search for life via characterization of earth-like planets in the habitable zone is one of the key scientific objectives in Astronomy. We describe a new phase-occulting (PO) interferometric nulling coronagraphy (NC) approach. The PO-NC approach employs beamwalk and freeform optical surfaces internal to the interferometer cavity to introduce a radially dependent plate scale difference between each interferometer arm (optical path) that nulls the central star at high contrast while transmitting the off-axis field. The design is readily implemented on segmented-mirror telescope architectures, utilizing a single nulling interferometer to achieve high throughput, a small inner working angle (IWA), sixth-order or higher starlight suppression, and full off-axis discovery space, a combination of features that other coronagraph designs generally must trade. Unlike previous NC approaches, the PO-NC approach does not require pupil shearing; this increases throughput and renders it less sensitive to on-axis common-mo...

  12. Staff dosimetry and risk assessment during digestive and angiographic examinations

    International Nuclear Information System (INIS)

    The use of ionizing radiation in medical applications involves not only a risk for the patient, but also for the staff which executed the related examinations. The dose to the forehead, neck, fingers and wrist of a radiologist and an assisting nurse were measured with thermoluminescent dosimeters during angiographic and digestive examinations respectively. Dose to eye lenses and effective dose were estimated for a working period of one year. Effective doses were under the established limit of 20 mSv per year. Nurse eye lens dose was higher than the limit of 150 mSv. Differences of a factor of 3.8 were observed between nurse and radiologist doses. Angiographic procedures are considered as high risk examinations, however, digestive examinations can have a higher risk than interventional procedures. (author)

  13. Management of complicated perspired pleural, by means of angiographic catheters

    International Nuclear Information System (INIS)

    Based on the recent literature and to demonstrate that complicated exudate drainage through angiographic catheters is a safe and efficient technique that offers a very useful alternative as a first choice treatment and also as a secondary treatment in the cases where thoracotomy tubes have failed, we have designed this scheme, in 28 patients with pleural effusion by radiographic evidence with a 52.7 average age and that fulfilled the light criteria for complicated pleural effusions, we accomplished drainage of the pleural effusion, using angiographic catheters, under ultrasound guidance. In the drainages that were realized, there was an 85.72% rate of success. it is important to mention that of the remaining 14.28% that presented pleural fluid after the drainage, none required surgery. 71.42% of the patients were treated only with angiographic catheters, while the remaining 28.57% were treated with them, after a failed drainage with thoracotomy tubes. The necessary time for the drainage was between 3 and 14 days. There were no complications during the catheter placement procedure neither during the time required for drainage of the pleural effusion

  14. PICO: Portable Instrument for Capturing Occultations

    Science.gov (United States)

    Lockhart, Matthew; Person, Michael J.; Elliot, J. L.; Souza, Steven P.

    2010-10-01

    We describe a portable imaging photometer for the observation of stellar occultation events by Kuiper Belt objects (KBOs) and other small bodies. The system is referred to as the Portable Instrument for Capturing Occultations (PICO). It is designed to be transportable to remote observing sites by a single observer. A GPS timing system is used to trigger exposures of a Finger Lakes Instrumentation ML261E-25 camera to facilitate the combination of observational results from multiple sites. The system weighs a total of 11 kg when packed into its single rigid 55.1 × 35.8 × 22.6 cm container, meeting current airline size and weight limits for carry-on baggage. Twelve such systems have been constructed. Nine systems were deployed for observation of a stellar occultation by Kuiper Belt object 55636 in 2009 October. During the same month, one system was used to record a stellar occultation by minor planet 762 Pulcova.

  15. McDonald's and the Occult.

    Science.gov (United States)

    Singer, Barry

    1979-01-01

    Discusses "occult" and "paranormal" literature which is often mistaken for nonfiction. Suggests that most publishers are unwilling to publish scientific perspectives on the paranormal because such writings would be unmarketable. Journal availability: see SO 507 190. (KC)

  16. Occultation Searches for Kuiper Belt Objects

    CERN Document Server

    Cooray, A R; Cooray, Asantha; Farmer, Alison J.

    2003-01-01

    The occultation of background stellar sources by foreground Kuiper Belt Objects (KBOs) can be used to survey physical properties of the KBO population. We discuss statistics related to a KBO occultation survey, such as the event duration distribution, and suggest that occultation searches can be effectively used to probe the KBO size distribution below 10 km. In particular, we suggest that occultation surveys may be best suited to search for a turnover radius in the KBO size distribution due to collisions between small-size objects. For occultation surveys that monitor stellar sources near the ecliptic over a few square degrees, with time sampling intervals of order 0.1 sec and sensitivity to flux variations of a few percent or more, a turnover radius between 0.1 and 1.0 km can be probed. While occultation surveys will probe the low-radius limit and imaging surveys will detect KBOs of size 100 km or more, statistics of objects with sizes in the intermediate range of around 1 km to 100 km will likely remain un...

  17. Radio occultation measurements of the lunar ionosphere.

    Science.gov (United States)

    Pluchino, S.; Schillirò, F.; Salerno, E.; Pupillo, G.; Maccaferri, G.; Cassaro, P.

    Radio occultation measurements by using interplanetary probes is a well known technique to obtain information on planetary atmospheres. To further understand the morphology of the lunar ionosphere we performed radio occultation experiments by using the radio sounding technique. This method mainly consists in the analisys of the effects produced on the radio wave transmitted from the spacecraft to the Earth when it crosses the atmosphere. The wave amplitude and phase undergo modifications that are correlated to the physical parameters - i.e. electron density - of the crossed medium. The first data set was obtained during the lunar occultations of the European probe SMART-1 shortly before impacting the lunar soil on September 3rd, 2006. During this experiment several radio occultation measurements of the signal transmitted by the spacecraft were performed in S and X band by using the 32 meters radiotelescopes (at Medicina and Noto) of the Istituto di Radioastronomia - Istituto Nazionale di Astrofisica. Further experiments were performed during lunar occultations of Saturn and Venus. On May 22nd and June 18th 2007 the Cassini spacecraft, orbiting Saturn, and the Venus Express spacecraft, orbiting Venus, respectively were occulted by the Moon. The variation of the Total Electron Content (TEC) measured by our instruments (˜ 1013 el/m2) on this occasion is in agreement with values of the electron number density acquired by in situ measuments of the US Apollo missions and the USSR Luna 19 and 22 probes.

  18. Method of Modeling and Simulation of Shaped External Occulters

    Science.gov (United States)

    Lyon, Richard G. (Inventor); Clampin, Mark (Inventor); Petrone, Peter, III (Inventor)

    2016-01-01

    The present invention relates to modeling an external occulter including: providing at least one processor executing program code to implement a simulation system, the program code including: providing an external occulter having a plurality of petals, the occulter being coupled to a telescope; and propagating light from the occulter to a telescope aperture of the telescope by scalar Fresnel propagation, by: obtaining an incident field strength at a predetermined wavelength at an occulter surface; obtaining a field propagation from the occulter to the telescope aperture using a Fresnel integral; modeling a celestial object at differing field angles by shifting a location of a shadow cast by the occulter on the telescope aperture; calculating an intensity of the occulter shadow on the telescope aperture; and applying a telescope aperture mask to a field of the occulter shadow, and propagating the light to a focal plane of the telescope via FFT techniques.

  19. Progress on an external occulter testbed at flight Fresnel numbers

    Science.gov (United States)

    Kim, Yunjong; Sirbu, Dan; Galvin, Michael; Kasdin, N. Jeremy; Vanderbei, Robert J.

    2016-01-01

    An external occulter is a spacecraft flown along the line-of-sight of a space telescope to suppress starlight and enable high-contrast direct imaging of exoplanets. Laboratory verification of occulter designs is necessary to validate the optical models used to design and predict occulter performance. At Princeton, we have designed and built a testbed that allows verification of scaled occulter designs whose suppressed shadow is mathematically identical to that of space occulters. The occulter testbed uses 78 m optical propagation distance to realize the flight Fresnel numbers. We will use an etched silicon mask as the occulter. The occulter is illuminated by a diverging laser beam to reduce the aberrations from the optics before the occulter. Here, we present first light result of a sample design operating at a flight Fresnel number and the mechanical design of the testbed. We compare the experimental results with simulations that predict the ultimate contrast performance.

  20. Evaluation of vascular pathologies with MR angiography

    International Nuclear Information System (INIS)

    The flow sensitivity of MR imaging methods can be used to visualize vascular structures (MR angiography). In this paper the method of flow-enhanced three-dimensional MR angiography will be presented. This technique makes use of the signal enhancement due to inflow of unsaturated spins into the imaging volume in combination with flow-compensated three-dimensional Fourier transform gradient-echo sequences. Projective images are calculated from the measured data by means of a maximum-intensity algorithm. The procedure was optimized for the visualization of the intra-and extracranial vasculature. The purpose of this study was to demonstrate the potential of this MR angiographic procedure to evaluate vascular disease in a clinical situation. Prospective studies in patients with vascular disease including aneurysms, arteriovenous malformations, arterial occlusion, and stenosis are shown in correlation with conventional procedures

  1. Neovascularization associated with large retinal pigment epithelial detachment in elderly Korean patients. Subdivision according to indocyanine green angiographic features

    International Nuclear Information System (INIS)

    In Korean patients, to subdivide the neovascular forms of age-related macular degeneration (AMD) associated with large retinal pigment epithelial detachment (PED), according to the indocyanine green angiographic features. Indocyanine green angiograms (ICGA) of 67 elderly patients (72 eyes) who presented with a PED of at least 1 disc diameter were evaluated retrospectively. Polypoidal choroidal vasculopathy (PCV) and typical choroidal neovascularization (CNV)-associated PEDs were identified in 18 eyes (25%) and 19 eyes (26%), respectively. In ten eyes (13.9%), the exact type of neovascularization, whether PCV or CNV, could not be determined. Pure serous PEDs were identified in seven eyes (10%). The remaining 18 eyes (25%) were classified as having retinal angiomatous proliferation (RAP)-associated PED based upon the angiographic findings of vascular connections between the retinal vasculature and the neovascular complex. Three subset groups of PCV, CNV, and RAP were present with similar frequency in neovascularized AMD with a large PED in these Korean patients. In particular, RAP, previously thought to be rare in Asian patients, was found to be present with considerable frequency. (author)

  2. Brachytherapy using holmium-166 liquid balloon system for in-stent restenosis: 6 months clinical and angiographic follow-up

    International Nuclear Information System (INIS)

    In western country, 3 systems of brachytherapy using commercial radioactive source has been established. However, brachytherapy using holmium-166 liquid balloon system (HLBS) for the patient with stent restenosis has not been studied enough. 30 patients (male 23, mean age 58.9 7.7) were enrolled. Target dose was 15 Gy at 1 mm distance from the intimal surface. Clinical diagnoses of the study patients included stable angina 10 and unstable angina 20 patients. Target lesion included LAD 19, LCx 5 and RCA 6 arteries. Pre-brachytherapy treatment included cutting balloon angioplasty in 25, rotational atherectomy in 5 patients. Fractionation and stepping was done in 6 patients each. Follow-up angiography was done in 19 patients. Of them, 4 cases developed angiographic restenosis (21%) including 3 cases of total occlusion. 6 month MACE (major adverse cardiac event) occurred in 5 patients including one sudden cardiac death in a patient with 80 year-old, triple-vessel diseased patient. Vascular brachytherapy using HLBS is a safe and effective treatment modality for in-stent restenosis showing acceptable angiographic and clinical result

  3. Ring Orbits from Multiple Occultation Observations

    Science.gov (United States)

    French, Richard G.; McGhee, C. A.; Marouf, E. A.; Rappaport, N.

    2006-09-01

    Planetary rings provide a remarkable laboratory for the investigation of a wide range of dynamical effects, including resonance-driven density and bending waves, satellite wakes, shepherding of narrow ringlets, and non-circular edges of gaps. Careful quantitative examination of these features requires a very accurate absolute radius scale and planetary pole direction, achievable by combining multiple stellar and radio occultation observations. Uncertainty in the location of the spacecraft (at the km level) introduces a fundamental uncertainty into the geometric solution for the ring radius scale, and in the end one must solve for corrections to the spacecraft trajectory as part of the overall determination of the ring orbital model. Using JPL's NAIF toolkit, we have developed accurate algorithms for computing the event time of a ring occultation during an Earth-based or spacecraft occultation, including the effects of spacecraft trajectory errors mapped in two orthogonal directions transverse to the line of sight, based on osculating orbital elements for the instantaneous spacecraft path. These are the fundamental building blocks for a global solution for the pole direction and orbits of the rings of Saturn and Uranus. For Uranus, our new orbit solution includes the full set of digitally recorded occultation data from 1977-2002, yielding a radius scale accurate at the 100 meter level. For Saturn, we explore the potential for highly accurate ring orbit determination as occultation observations from dozens of stellar and radio occultations become publicly available over the course of the ongoing Cassini orbital tour. Saturn's pole precession is also detectable from ring occultation data, and we set limits on the accuracy of the precession rate determination and the implications for our understanding of the mass distribution in Saturn's interior. This work was supported in part by the NASA PGG program.

  4. Radiation doses to personnel during common angiographic procedures involving DSA

    International Nuclear Information System (INIS)

    In this study, the radiation doses received by the staff are monitored during common angiographic procedures involving digital subtraction angiography (DSA). Doses are assessed by direct measurement using lithium fluoride thermoluminescent dosemeters (TLDs). The entrance surface dose (mGy) at the different locations on each of the staff for the three different procedures are given. As the result, on the whole, the main operator, who is standing closest to the x-ray tube and patient, receive the highest dose while the radiographer receives the lowest dose

  5. Clinical-pathological-angiographic correlations following transluminal atherectomy

    International Nuclear Information System (INIS)

    Following percutaneous atherectomy, arterial and catheter diameter relationships were correlated with angiographic and ankle-arm index results. There was a greater amount of tissue removed, improved luminal reconstitution, and ankle-arm index in lesions where the catheter and arterial diameters were equal or within 0.5 mm. Excluding lesions requiring angioplasty, 77% of our lesions had less than 30% residual stenosis; including lesions requiring concomitant angioplasty, the initial overall patency was 93%, with a 1-year patency rate of 92.5%. This study indicates that adequate matching of the atherectomy catheter diameter to the arterial diameter is necessary to optimize tissue removal and clinical results

  6. First Stellar Occultation Observation with SOFIA

    Science.gov (United States)

    Dunham, Edward W.; Bida, T.; Bosh, A.; Collins, P.; Levine, S.; Person, M.; Pfueller, E.; Roeser, H.; Taylor, B.; Wiedemann, M.; Wolf, J.; Zuluaga, C.

    2012-01-01

    We successfully observed the 2011 June 23 UT stellar occultation by Pluto with the High-speed Imaging Photometer for Occultations (HIPO) instrument from Lowell Observatory and the Fast Diagnostic Camera (FDC) from the Deutches SOFIA Institut (DSI) mounted on the SOFIA telescope. A major prediction astrometry effort focused at MIT combined with the willingness of the SOFIA project to entertain the idea of an in-flight change to the flight plan allowed us to target the center of the occultation shadow. This was accomplished by means of an in-flight prediction update by satellite telephone and a real-time onboard flight plan modification to accommodate the prediction update. We obtained excellent results with both channels of HIPO and the FDC with each light curve showing a small, extended brightening while the star was occulted. We will discuss analysis results as well as SOFIA's considerable potential for future occultation work. We thank the SOFIA program for its willingness to attempt this challenging observation at such an early stage of SOFIA science operations. Lowell's SOFIA work was supported by a grant from USRA, MIT's prediction work was supported by the NASA Planetary Astronomy Program and the National Science Foundation, and the FDC work was supported by the DSI. We thank the US Naval Observatory Flagstaff Station for allowing us to use their facilities to obtain our prediction astrometry observations.

  7. Comparison of angiographic, gammagraphic, and histological data in orbital tumours: concerning 13 observations

    International Nuclear Information System (INIS)

    The aim of this work is to compare the value of gammagraphic and angiographic examinations in intra-orbital expansive processes and to hole for a histological explanation when the two examinations disagree. All the gammagraphs used were obtained with technetium 99m-labelled ferrous ascorbate. Orbital gammagraphy requires a radioelement combining the advantages of easily detectable radioactivity and fast elimination from healthy tissues while keeping a strong tumoral uptake. Sup(99m)Tc-labelled ferrous ascorbate fulfils these conditions. Technetium 99m, perfectly safe because of its short half-life and low radiation energy, allows the scintigraphic detection of expansive processes. By its association with ferrous ascorbate, which has a very high kidney and plasma clearance rate, the vascular background is reduced considerably and the relative radiotracer concentration in the diseased area increased (the background is due to fixation of the radioelement in the facial and orbital muscles, the mucous membranes of the nose and sinus and the vein sinuses at the base of the skull). The complex used in this study is obtained from 40mg ferrous ascorbate to which are added 1ml Thris buffer at pH 7.85 and 5ml 99mTc pertechnetate solution. 10 to 15 microcuries are injected intraveinously or absorbed parenterally

  8. Effect of Asparagus racemosus on fracture healing in rabbits: a radiographic and angiographic study

    International Nuclear Information System (INIS)

    New Zealand white rabbits (18) were randomly divided into groups I and II (control) having 9 animals in each group. The fracture of ulna was created in each animal under general anaesthesia using thiopental sodium (2.5%). Radius acted as a natural splint. The animals of group I were fed with powdered Asparagus racemosus along with rabbit feed throughout the study period. However, in group II animals only powdered rabbit feed was given. Healing at the fracture site was assessed by plain radiography and angiography at 7th, 14th, 21st and 28th day interval. Radiographical observation revealed a well organized and dense callus at 21st day in animals of group I whereas in animals of group II, callus of slightly less radiographic density was observed at this interval. Angiographic observation revealed hypervascularity at the fracture site at 7th and 14th day interval in group I animals. On day 14, in group II animals major vessels lack continuity along with reduced vascularity around the fracture site. The results of present study suggest that feeding of dry root powder of Asparagus racemosus promotes early fracture healing in rabbits

  9. Angiographic features beyond 'open' and 'occluded'

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, K.

    1982-09-01

    In a patient presenting a swelling on the right big toe and ulceration on its end a very important acceleration of the blood flow was verified angiographically in the arteries of both lower extremities after a first injection of contrast medium. The arteriae tibialis anterior and posterior were not opacified in their whole length and narrowed on a second angiogramm with a more rapid sequence of the films. Despite of this fact the foot was hypervascularized. On a third injection the arteria tibialis posterior was normaly wide. The blood flow was considerably slowed on the foot, the number of the small vessels was increased, arteries and veins were filled simultaneously and the arteria plantaris pedis was obstructed in places. The temperature of the skin was raised on the big toe. The bones of the first toe and the metatarsale I were discreetly decalcified and the uptake was increased in the scintigram. These features were considered to be the expression of a neuroangiopathy with disturbed vascular reflexes. The aspect on the soft tissue of the toe (purple toe) was interpreted as a disturbance of trophism and not as a true occlusion gangren.

  10. Ipsilateral occult hernias during endoscopic groin hernia repair

    OpenAIRE

    Jain Mayank; Khanna Shashi; Sen Bimalendu; Tantia Om

    2008-01-01

    Endoscopic repair of groin hernias allows the surgeon to have a complete view of the groin and pelvis to diagnose occult hernias both ipsilaterally and contralaterally. These occult hernias can then be treated simultaneously and may reduce the incidence of recurrence and persistent symptoms. The authors present four unusual cases where occult hernias were found ipsilaterally during an endoscopic repair. All these occult hernias were treated along with the clinically diagnosed hernia at the sa...

  11. Precise measurement of asteroid sizes and shapes from occultations

    International Nuclear Information System (INIS)

    The observational techniques (including photoelectric observations, television recordings, and visual timings) used to measure asteroid dimensions from occultations of stars by asteroids are discussed together with the methods of analysis appropriate to occultation data. Results are presented on the determinations of asteroid diameter, density, and internal structure measures learned from occultations of 36 asteroids. Prospects for continued effective applications of the occultation technique to asteroid studies are discussed. 80 refs

  12. Ultrasonography of occult fractures: a pictorial essay

    International Nuclear Information System (INIS)

    Occult fractures are a common clinical problem with significant morbidity. All bones may be affected, and routine radiography, the first line of investigation, is often limited in its ability to detect these fractures, despite multiple views. Further investigations in patients with bone or joint-related pain after trauma may include computed tomography (CT), magnetic resonance imaging or radionuclide bone scan. These are relatively expensive imaging modalities. This pictorial essay demonstrates the use of high-resolution ultrasonography (US) in detecting occult fractures, and reviews the implication of its use for first- or second-line investigation in suspected occult fractures. A variety of examples of different fractures will be shown with comparative CT, plain film images or MRI. The added value of power Doppler imaging will also be illustrated. (author)

  13. Close Double Stars from Occultation Video Recordings

    Science.gov (United States)

    Waring Dunham, David; George, Anthony; Loader, Brian; Herald, David Russell

    2015-08-01

    Astronomers around the world, both amateur and professional, have been recording lunar and asteroidal occultations of close double stars during the past several years using inexpensive but quite sensitive video cameras that are now available. Several new double stars have been discovered, and the parameters of many close systems have been determined. Besides rather good measurements of the relative magnitudes of the components, the actual separations and position angles can be measured if observations of the same event are made from two or more separate stations. These observations collected by the International Occultation Timing Association (IOTA) are published in the Journal of Double Star Observations. Recently, IOTA has encouraged the observation of occultations of stars in the Kepler 2 program, which is interested in data about close duplicity that affects their analyses for exoplanet transits.

  14. Scintillation Caustics in Planetary Occultation Light Curves

    CERN Document Server

    Cooray, A R; Cooray, Asantha R.

    2003-01-01

    We revisit the GSC5249-01240 light curve obtained during its occultation by Saturn's North polar region. In addition to refractive scintillations, the power spectrum of intensity fluctuations shows an enhancement of power between refractive and diffractive regimes. We identify this excess power as due to high amplitude spikes in the light curve and suggest that these spikes are due to caustics associated with ray crossing situations. The flux variation in individual spikes follows the expected caustic behavior, including diffraction fringes which we have observed for the first time in a planetary occultation light curve. The presence of caustics in scintillation light curves require an inner scale cut off to the power spectrum of underlying density fluctuations associated with turbulence. Another possibility is the presence of gravity waves in the atmosphere. While occultation light curves previously showed the existence of refractive scintillations, a combination of small projected stellar size and a low rel...

  15. Evaluation for Occult Fractures in Injured Children

    Science.gov (United States)

    French, Benjamin; Song, Lihai; Feudtner, Chris

    2015-01-01

    OBJECTIVES: To examine variation across US hospitals in evaluation for occult fractures in (1) children physical abuse and (2) infants abuse and to identify factors associated with such variation. METHODS: We performed a retrospective study in children physical abuse and in infants abuse diagnosis, in 51% of the 1574 infants with traumatic brain injury, and in 53% of the 859 infants with femur fractures. Hospitals varied substantially with regard to their rates of evaluation for occult fractures in all 3 groups. Occult fracture evaluations were more likely to be performed at teaching hospitals than at nonteaching hospitals (all P abuse or injuries associated with a high likelihood of abuse highlights opportunities for quality improvement in this vulnerable population. PMID:26169425

  16. Angiographic diagnosis and interventional therapy for Takayasu arteritis

    International Nuclear Information System (INIS)

    Objective: To explore the value of angiographic diagnosis and interventional therapy for Takayasu arteritis. Methods: Thirty-eight patients with Takayasu Arteritis (TA) (11 men, 27 woman; aged 8-54; average age, 30.5 ± 18) undergone angiography were analyzed retrospectively. The angiographic appearances in all of the patients were observed dynamically in a double blind method by two experienced radiologists together and formed a consensus interpretation. Results: According to the classification of Lupi-Herrea, type I was found in 11 cases, type II in 15, type III in 7 and type IV in 5 by angiography. Among 38 patients the arterial involvement included subclavian artery in 20 cases (52.6%), the abdominal aorta in 15 cases (39.5%), the renal artery in 14 cases (36.8%), thoracic aorta in 10 cases (26.3%), carotid artery in 9 cases (23.7%), iliac artery in 9 cases (23.7%), axillary artery in 7 cases (18.4%), superior mesenteric artery in 4 cases (10.5%), coronary artery in 3 cases (7.9%), pulmonary artery in 3 cases (7.9%), and so on. Percutaneous transluminal angioplasty was performed in 22 cases and the stent placement was managed in 12 cases successfully. Conclusions: Angiography is one of the ideal and reliable methods for the diagnosis and guidance of the interventional treatment for TA, and the latter is a mini-invasive and effective way for TA. (authors)

  17. Ultrasonography and angiographic examination of normal canine liver vessels

    International Nuclear Information System (INIS)

    The aim of this study is to provide a description of the ultrasonographic and angiographic anatomy of the hepatic and portal veins in normal dogs. Knowledge of this anatomy is essential for the proper diagnosis and correction of hepatic vessel anomalies like portal systemic shunts. Cranial mesenteric portography was done in 10 adult mongrel dogs to visualize the portal vein and its branches while the hepatic veins were visualized using the transvenous retrograde angiography method. Longitudinal and transverse ultrasound scans of the liver were done in the same dogs in left and right lateral positions in order to determine the best positions for imaging the different liver vessels. The distribution pattern of the hepatic and portal veins could be demonstrated by both ultrasonography and contrast angiography. Hepatic arteries are not usually visualized ultrasonographically. Ultrasound provided dynamic information that could not be obtained by contrast radiography. Super imposition of all vessels in the angiographic studies made the description of the branches of the liver vessels difficult. The results of the present study suggest that both methods may provide important complementary information in the diagnosis and planning of surgical procedures for the correction of vessel anomalies in the canine liver

  18. Occult, massive hematomas following antegrade femoral angioplasty

    International Nuclear Information System (INIS)

    Small groin hematomas are not uncommon after percuatenous antegrade femoral angioplasty (PAFA) and are usually apparent clinically. The authors describe three patients of 235 who underwent PAFA, in whom occult, massive hemorrhage was detected after the procedure. All patients underwent fluoroscopically guided antegrade punctures, with adequate hemostasis achieved after the procedure. CT revealed extraperitoneal hematomas in two patients. One patient required surgical intervention with ligation of the inferior epigastric artery. The authors postulate that these hematomas arose due to inadvertent injury to a branch of the common femoral artery during the puncture. The radiologist should be aware of the chance occurrence of this occult, potentially life-threatening complication

  19. Altimetry Using GPS-Reflection/Occultation Interferometry

    Science.gov (United States)

    Cardellach, Estel; DeLaTorre, Manuel; Hajj, George A.; Ao, Chi

    2008-01-01

    A Global Positioning System (GPS)- reflection/occultation interferometry was examined as a means of altimetry of water and ice surfaces in polar regions. In GPS-reflection/occultation interferometry, a GPS receiver aboard a satellite in a low orbit around the Earth is used to determine the temporally varying carrier- phase delay between (1) one component of a signal from a GPS transmitter propagating directly through the atmosphere just as the GPS transmitter falls below the horizon and (2) another component of the same signal, propagating along a slightly different path, reflected at glancing incidence upon the water or ice surface.

  20. The Radio Occultation Processing Package ROPP

    Directory of Open Access Journals (Sweden)

    I. D. Culverwell

    2015-01-01

    Full Text Available This paper describes the Radio Occultation Processing Package, ROPP, a product of the EUMETSAT Radio Occultation Meteorology Satellite Application Facility (ROM SAF developed by a large number of scientists over many years. A brief review of the concepts, functionality and structure of ROPP is followed by more detailed descriptions of its key capabilities. Example results from a full chain of processing using some of the ROPP tools are presented. Some current and prospective uses of ROPP are given. Instructions on how to access the code and its supporting documentation are provided.

  1. Calcification of the intracranial carotid artery and its relation to the clinical and angiographic picture: an angiographic classification of asteriosclerosis cerebri

    Directory of Open Access Journals (Sweden)

    Valter Seixas

    1968-03-01

    Full Text Available Fifty six patients with arteriosclerosis cerebri confirmed by X-rays examinations were clinically and angiographically studied. Calcifications of the carotid artery were found predominantly in human beings between the ages of 55 and 65 and more often among men than among women, the proportion being 2.5 to 1. Nearly all arteriosclerotic patients with calcium deposits in the carotid artery showed several neurological and mental deficits, the most frequent initial symptoms being motor disturbances. Angiographic anormalities found in these patients can be classed into 3 groups: (a grade I— wavy course of the cerebral vessels, small number of peripheral brain vessels, formation of small knots, prolonged circulation time, arteria cerebri anterior with angular form, straight course and broad caliber; (b grade II— partial block, irregularities of wall and caliber, aneurysmal formations; (c grade III— total block of some vessels of the carotid system preventing a generalized or localized cerebral blood supply. Grades II and III angiographic abnormalities were most often seen at the syphon and at the carotid bifurcation in the neck (site of predilection. Most patients with a progressive clinical course belonged to the I group. The course of the disease did not differ in patients with grades II and III angiographic changes since usually the illness had an apoplectiform onset. Arteriosclerotic degenerative irregularities within the layers of the arteries (up to atheromatous patches may occur without reducing the arterial lumen. In such cases the patients may remain asymptomatic until there is a decompensation in the brain circulation due to many causes.Foram estudados, clínica e angiogràficamente, 56 pacientes com arte-riosclerose cerebral comprovada mediante visibilização radiológica de calcificações localizadas na porção intracraniana da artéria carótida interna. Calcificações da artéria carótida interna ocorrem com mais freq

  2. Clues to occult cancer in patients with ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Suk Jae Kim

    Full Text Available BACKGROUND: We hypothesized that hidden malignancy could be detected in patients with cryptogenic stroke without active cancer when they showed the distinctive characteristics of cancer-related stroke. METHODS AND FINDINGS: Among 2,562 consecutive patients with acute ischemic stroke, patients with cryptogenic stroke were analyzed and categorized into two groups according to the presence of active cancer: cryptogenic stroke with active cancer (cancer-related stroke, CA-stroke group and without active cancer (CR-stroke group. Patients with active lung cancer without stroke were also recruited for comparison purposes (CA-control. Clinical factors, lesion patterns on diffusion-weighted MRI (DWI, and laboratory findings were analyzed among groups. A total of 348 patients with cryptogenic stroke were enrolled in this study. Among them, 71 (20.4% patients had active cancer at the time of stroke. The D-dimer levels were significantly higher in patients with CA-stroke than those with CR-stroke or CA-control (both p<0.001. Regarding lesion patterns, patients with CA-stroke mostly had multiple lesions in multiple vascular territories, while more than 80% of patients with CR-stroke had single/multiple lesions in a single vascular territory (P<0.001. D-dimer levels (OR 1.11 per 1 µg/mL increase; 95% CI 1.06-1.15; P<0.001 and DWI lesion patterns (OR 7.13; 95% CI 3.42-14.87; P<0.001 were independently associated with CA-stroke. Workup for hidden malignancy was performed during hospitalization in 10 patients who showed elevated D-dimer levels and multiple infarcts involving multiple vascular territories but had no known cancer, and it revealed hidden malignancies in all the patients. CONCLUSION: Patients with CA-stroke have distinctive D-dimer levels and lesion patterns. These characteristics can serve as clues to occult cancer in patients with cryptogenic stroke.

  3. Persistent monoarthritis and occult coeliac disease.

    OpenAIRE

    Borg, A A; Dawes, P T; Swan, C H; Hothersall, T E

    1994-01-01

    Arthritis is a recognized complication of untreated coeliac disease. Symptoms and signs usually respond to the institution of a gluten-free diet. We report a case of occult coeliac disease presenting as a monoarthritis. Severe and progressive erosive damage has occurred in his talo-navicular joint despite a response to the institution of a gluten-free diet.

  4. Controversies about occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Ersan Ozaslan; Tugrul Purnak

    2009-01-01

    We read with great interest the paper written by Shi et al, reviewing the molecular characteristics and stages of chronic hepatitis B virus (HBV) infection. We think that some points in the definition of occult HBV infection (OBI) and their conclusion about the management of OBI may need further considerations.

  5. Occult spondyloarthritis in inflammatory bowel disease.

    Science.gov (United States)

    Bandinelli, Francesca; Manetti, Mirko; Ibba-Manneschi, Lidia

    2016-02-01

    Spondyloarthritis (SpA) is a frequent extra-intestinal manifestation in patients with inflammatory bowel disease (IBD), although its real diffusion is commonly considered underestimated. Abnormalities in the microbioma and genetic predisposition have been implicated in the link between bowel and joint inflammation. Otherwise, up to date, pathogenetic mechanisms are still largely unknown and the exact influence of the bowel activity on rheumatic manifestations is not clearly explained. Due to evidence-based results of clinical studies, the interest on clinically asymptomatic SpA in IBD patients increased in the last few years. Actually, occult enthesitis and sacroiliitis are discovered in high percentages of IBD patients by different imaging techniques, mainly enthesis ultrasound (US) and sacroiliac joint X-ray examinations. Several diagnostic approaches and biomarkers have been proposed in an attempt to correctly classify and diagnose clinically occult joint manifestations and to define clusters of risk for patient screening, although definitive results are still lacking. The correct recognition of occult SpA in IBD requires an integrated multidisciplinary approach in order to identify common diagnostic and therapeutic strategies. The use of inexpensive and rapid imaging techniques, such as US and X-ray, should be routinely included in daily clinical practice and trials to correctly evaluate occult SpA, thus preventing future disability and worsening of quality of life in IBD patients. PMID:26354428

  6. Occult hepatitis B infection: an evolutionary scenario

    Directory of Open Access Journals (Sweden)

    Lukashov Vladimir V

    2008-12-01

    Full Text Available Abstract Background Occult or latent hepatitis B virus (HBV infection is defined as infection with detectable HBV DNA and undetectable surface antigen (HBsAg in patients' blood. The cause of an overt HBV infection becoming an occult one is unknown. To gain insight into the mechanism of the development of occult infection, we compared the full-length HBV genome from a blood donor carrying an occult infection (d4 with global genotype D genomes. Results The phylogenetic analysis of polymerase, core and X protein sequences did not distinguish d4 from other genotype D strains. Yet, d4 surface protein formed the evolutionary outgroup relative to all other genotype D strains. Its evolutionary branch was the only one where accumulation of substitutions suggests positive selection (dN/dS = 1.3787. Many of these substitutiions accumulated specifically in regions encoding the core/surface protein interface, as revealed in a 3D-modeled protein complex. We identified a novel RNA splicing event (deleting nucleotides 2986-202 that abolishes surface protein gene expression without affecting polymerase, core and X-protein related functions. Genotype D strains differ in their ability to perform this 2986-202 splicing. Strains prone to 2986-202 splicing constitute a separate clade in a phylogenetic tree of genotype D HBVs. A single substitution (G173T that is associated with clade membership alters the local RNA secondary structure and is proposed to affect splicing efficiency at the 202 acceptor site. Conclusion We propose an evolutionary scenario for occult HBV infection, in which 2986-202 splicing generates intracellular virus particles devoid of surface protein, which subsequently accumulates mutations due to relaxation of coding constraints. Such viruses are deficient of autonomous propagation and cannot leave the host cell until it is lysed.

  7. Clinical Investigation of Radiation Retinopathy Fundus and Fluorescein Angiographic Features

    Institute of Scientific and Technical Information of China (English)

    LiMei; QiuGT

    1999-01-01

    Purpose:To investigate the fundus and fluorescein angiographic features in the patients with radiation retinopathy.Clinical Materials:Color fundus photography and/or fluorescein angiography from 13 patients with nasopharyngeal carcinomas received external beam radiation were retrospectively analyzed.Reslts:In this study,26 damaged eyes of 13 patients eveloped some degree of radiation retinopathy.The earliest and most common finding was macular microvascular changes (microaneurysms and/or telangiectasia),which was observed in 100%(26/26)of the eyes.Intraretinal hemorrhages,macular capillary nonperfusion,and macular edema were noted in 84%,50%,and 42% of the eyes,respectively.Conclusions:Radiation retinopathy is common after external beam radiation of nasopharyngeal carcinomas.The prominent changes include maular microvascular changes,intraretinal hemorrhages and macular capillary nonperfusion.

  8. Angiography in the Isolated Perfused Kidney: Radiological Evaluation of Vascular Protection in Tissue Ablation by Nonthermal Irreversible Electroporation

    International Nuclear Information System (INIS)

    Purpose: The nonthermal irreversible electroporation (NTIRE) is a novel nonthermal tissue ablation technique by local application of high-voltage current within microseconds leading to a delayed apoptosis. The purpose of this experimental study was the first angiographic evaluation of the acute damage of renal vascular structure in NTIRE. Methods: Results of conventional dynamic digital substraction angiography (DSA) and visualization of the terminal vascular bed of renal parenchyma by high-resolution X-ray in mammography technique were evaluated before, during, and after NTIRE of three isolated perfused porcine ex vivo kidneys. Results: In the dedicated investigation, no acute vascular destruction of the renal parenchyma and no dysfunction of the kidney perfusion model were observed during or after NTIRE. Conspicuous were concentric wave-like fluctuations of the DSA contrast agent simultaneous to the NTIRE pulses resulting from NTIRE pulse shock wave. Conclusion: The NTIRE offers an ablation method with no acute collateral vascular damage in angiographic evaluation.

  9. Vascular MR

    International Nuclear Information System (INIS)

    This project investigates cardiac gated gradient echo pulses sequences for vascular MR imaging. These pulse sequences have been used to acquire and display MR projection angiograms. The authors have applied these methods in two distinct populations of patients for evaluation and comparison with standard angiography. Twenty patients with abdominal aortic aneurysms, and 35 patients with aortoiliac atherosclerotic disease or peripheral vascular disease were investigated using this method and the results are presented

  10. Vascular Dementia

    OpenAIRE

    Maria Alekseyevna Cherdak; O. V. Uspenskaya

    2015-01-01

    Vascular dementia is one of the most common causes of dementia after Alzheimer's disease, causing around 15% of cases. However, unlike Alzheimer's disease, there are no licensed treatments for vascular dementia. Progress in the specialty has been difficult because of uncertainties over disease classification and diagnostic criteria, controversy over the exact nature of the relation between cerebrovascular pathology and cognitive impairment, and the paucity of identifiable tractable treatment ...

  11. Interventional spinal procedures guided and controlled by a 3D rotational angiographic unit

    Energy Technology Data Exchange (ETDEWEB)

    Pedicelli, Alessandro; Verdolotti, Tommaso; Desiderio, Flora; D' Argento, Francesco; Colosimo, Cesare; Bonomo, Lorenzo [Catholic University of Rome, A. Gemelli Hospital, Department of Bioimaging and Radiological Sciences, Rome (Italy); Pompucci, Angelo [Catholic University of Rome, A. Gemelli Hospital, Department of Neurotraumatology, Rome (Italy)

    2011-12-15

    The aim of this paper is to demonstrate the usefulness of 2D multiplanar reformatting images (MPR) obtained from rotational acquisitions with cone-beam computed tomography technology during percutaneous extra-vascular spinal procedures performed in the angiography suite. We used a 3D rotational angiographic unit with a flat panel detector. MPR images were obtained from a rotational acquisition of 8 s (240 images at 30 fps), tube rotation of 180 and after post-processing of 5 s by a local work-station. Multislice CT (MSCT) is the best guidance system for spinal approaches permitting direct tomographic visualization of each spinal structure. Many operators, however, are trained with fluoroscopy, it is less expensive, allows real-time guidance, and in many centers the angiography suite is more frequently available for percutaneous procedures. We present our 6-year experience in fluoroscopy-guided spinal procedures, which were performed under different conditions using MPR images. We illustrate cases of vertebroplasty, epidural injections, selective foraminal nerve root block, facet block, percutaneous treatment of disc herniation and spine biopsy, all performed with the help of MPR images for guidance and control in the event of difficult or anatomically complex access. The integrated use of ''CT-like'' MPR images allows the execution of spinal procedures under fluoroscopy guidance alone in all cases of dorso-lumbar access, with evident limitation of risks and complications, and without need for recourse to MSCT guidance, thus eliminating CT-room time (often bearing high diagnostic charges), and avoiding organizational problems for procedures that need, for example, combined use of a C-arm in the CT room. (orig.)

  12. Outcome of endovascular treatment in symptomatic intracranial vascular stenosis

    International Nuclear Information System (INIS)

    The outcome evaluation for the revascularization of intracranial vascular stenoses has not been fully described due to the highly technical nature of the procedure. We report here on the early and late clinical outcome of angioplasty and/or stenting of symptomatic severe intracranial vascular stenoses at a single institute. Since 1995, we have treated 35 patients with symptomatic intracranial vascular stenosis (more than 70% stenosis, mean stenosis: 78.6% ± 6.2%). Angioplasty (n = 19) was performed for the horizontal segment of the middle cerebral artery (M1) (n = 16) and the basilar artery (BA) (n = 1), the intradural vertebral artery (VA) (n = 1), and the cavernous internal carotid artery (ICA) (n = 1). Stenting (n = 16) was performed for the cavernous or petrous ICAs (n = 9), the intradural VA (n = 3), BA (n = 2), and M1 (n = 2) artery. We assessed the angiographic success (defined as residual stenosis < 50%) rate, the periprocedural complications during the 30-day periprocedural period, the symptomatic recurrence and restenosis during a mean 22-month follow-up (FU) period. The Kaplan-Meier estimate of the cumulative even-free rate of the major cerebrovascular events, i.e. death, stroke or restenosis, was also done. Angiographic success was achieved in 97% of our patients (34/35). There were four procedure-related complications (11%) including a death and a minor stroke. During the mean 22-month FU, the asymptomatic restenosis rate was 9% and the symptomatic restenosis rate was 6% in the target lesion and 9% in all the vascular territories. The Kaplan-Meier estimate was 70.6% (95% confidence interval = 46.5-94.7) after 33 month of FU. In addition to a high angiographic success rate and an acceptable periprocedural complication rate, intracranial angioplasty and/or stenting revealed a relatively low symptomatic recurrence rate. Hemorrhage is a rare, but the physician must aware that potentially fatal periprocedural complications can occur

  13. Certain aspects of angiographic picture of clear cell carcinoma of the kidney

    International Nuclear Information System (INIS)

    The results of retrospective analysis of some forms of atypic angiographic manifestations of clear cell carcinoma of the kidney, found in 28 out of 302 patients observed for kidney tumor, are presented. The correlation of angiographic data with macroscopic structure of the tumor in this group of patients has enabled one to establish some factors, promoting certain deviations from a typical angiographic picture of the kidney cell carcinoma. It has been shown that the clear latter could have been caused by the following aspects of tumor growth: (i) the prevalence of necrotic alterations along with calcification in the tumor, (ii) mostly infiltrative type of tumor growth with diffuse spreading in the organ (iii) extraparenchymatous localization of the tumor. Because of the above mentioned aspects of angiographic manifestation of the kidney tumor, diagnostic mistakes have been made in 5 of 28 patients. The rest of the cases have presented certain difficulties in differential diagnosis

  14. CASSINI UVIS STELLAR OCCULTATION OBSERVATIONS OF SATURN's RINGS

    International Nuclear Information System (INIS)

    The Cassini spacecraft's Ultraviolet Imaging Spectrograph (UVIS) includes a high-speed photometer (HSP) that has observed more than 100 stellar occultations by Saturn's rings. Here, we document a standardized technique applied to the UVIS-HSP ring occultation datasets delivered to the Planetary Data System as higher level data products. These observations provide measurements of ring structure that approaches the scale of the largest common ring particles (∼5 m). The combination of multiple occultations at different viewing geometries enables reconstruction of the three-dimensional structure of the rings. This inversion of the occultation data depends on accurate calibration of the data so that occultations of different stars taken at different times and under different viewing conditions can be combined to retrieve ring structure. We provide examples of the structure of the rings as seen from several occultations at different incidence angles to the rings, illustrating changes in the apparent structure with viewing geometry.

  15. The JWST/NIRCam Coronagraph Flight Occulters

    Science.gov (United States)

    Krist, John E.; Balasubramanian, Kunjithapatham; Muller, Richard E.; Shaklan, Stuart B.; Kelly, Douglas M.; Wilson, Daniel W.; Beichman, Charles A.; Serabyn, Eugene; Mao, Yalan; Echternach, Pierre M.; Trauger, John T.; Liewer, Kurt M.

    2010-01-01

    The NIRCam instrument on the James Webb Space Telescope will have a Lyot coronagraph for high contrast imaging of extrasolar planets and circumstellar disks at lambda = 2 - 5 micrometers. Half-tone patterns are used to create graded-transmission image plane masks. These are generated using electron beam lithography and reactive ion etching of a metal layer on an antireflection coated sapphire substrate. We report here on the manufacture and evaluation of the flight occulters.

  16. Convective towers detection using GPS radio occultations

    OpenAIRE

    Biondi, Riccardo; Neubert, Torsten; Syndergaard, S.; Nielsen, J.

    2010-01-01

    The tropical deep convection affects the radiation balance of the atmosphere changing the water vapour mixing ratio and the temperature of the upper troposphere and lower stratosphere. To gain a better understanding of deep convective processes, the study of tropical cyclones could play an important role since they lead to deep convective activity. With this work we want to investigate if severe storms leave a significant signature in radio occultation profiles in the tropical tropopause laye...

  17. The JWST/NIRCam coronagraph flight occulters

    Science.gov (United States)

    Krist, John E.; Balasubramanian, Kunjithapatham; Muller, Richard E.; Shaklan, Stuart B.; Kelly, Douglas M.; Wilson, Daniel W.; Beichman, Charles A.; Serabyn, Eugene; Mao, Yalan; Echternach, Pierre M.; Trauger, John T.; Liewer, Kurt M.

    2010-07-01

    The NIRCam instrument on the James Webb Space Telescope will have a Lyot coronagraph for high contrast imaging of extrasolar planets and circumstellar disks at λ=2 - 5 μm. Half-tone patterns are used to create graded-transmission image plane masks. These are generated using electron beam lithography and reactive ion etching of a metal layer on an antireflection coated sapphire substrate. We report here on the manufacture and evaluation of the flight occulters.

  18. Relationship between Angiographic Late Loss and 5-Year Clinical Outcome after Drug-Eluting Stent Implantation

    OpenAIRE

    Yang, Young-June; Shin, Sanghoon; Kim, Byeong-Keuk; Kim, Jung-Sun; Shin, Dong-Ho; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo; Hong, Myeong-Ki

    2012-01-01

    Purpose Currently, insufficient data exist to evaluate the relationship between angiographic late loss (LL) and long-term clinical outcome after drug-eluting stent (DES) implantation. In this study, we hypothesized that angiographic LL between 0.3 and 0.6 mm correlate with favorable long-term clinical outcomes. Materials and Methods Patients were enrolled in the present study if they had undergone both DES implantation in single coronary vessel and a subsequent follow-up angiogram (n=634). Th...

  19. Clinical and angiographic features associated with coronary collateralization in stable angina patients with chronic total occlusion

    OpenAIRE

    Sun, Zhen; Shen, Ying; Lu, Lin; Zhang, Rui-yan; Pu, Li-jin; Zhang, Qi; Yang, Zheng-kun; Hu, Jian; Chen, Qiu-jing; Shen, Wei-Feng

    2013-01-01

    Objective: Coronary collateral circulation is an alternative source of blood supply to myocardium in the presence of advanced coronary artery disease. We sought to determine which clinical and angiographic variables are associated with collateral development in patients with stable angina and chronic total coronary occlusion. Methods: Demographic variables, biochemical measurements, and angiographic findings were collected from 478 patients with stable angina and chronic total coronary occlus...

  20. 3D Reconstruction of Coronary Arteries from Angiographic Images: A Survey

    OpenAIRE

    Mahima Goyal; Jian Yang; Arun PrakashAgrawal

    2013-01-01

    X-Ray angiographyis considered to be the “golden standard” ofall times in the medical imaging field due to its wide range ofapplications. In this paper, a survey is performed on the basictechniques and the methodologies that have already beenproposed by various researchers in the field of 3D reconstructionof coronary arteries using one or more angiograms as inmonoplane or biplane angiographic systems or a volume of dataas in rotational angiographic systems. Also, the variousprocedures that ne...

  1. Significance and specificity of vascular anastomosis in liver transplantation: Our experience

    Directory of Open Access Journals (Sweden)

    Nenezić Dragoslav

    2007-01-01

    Full Text Available Introduction Transplantation is the method of choice in the treatment of terminal liver diseases with acute and structural damage of liver tissue and congenital liver diseases. Objective The aim of our study was to determine specificity and significance of vascular anastomosis in liver transplantation by postoperative evaluation of vascular anastomosis function. Method The study included 16 patients with 16 liver transplantations and one re-do liver transplantation. In all patients, preoperative angiography and postoperative duplex sonographic and angiographic evaluation of vascular anastomosis were performed. Results Preoperative angiographic evaluation did not reveal anomalies in liver blood vessels of transplant candidates. In one patient, we identified and angiographically confirmed stenosis on anastomosis of the hepatic artery on the 7th postoperative day. In another patient, we had artificial thrombosis of the hepatic artery branch due to the liver biopsy. Conclusion The successful performance of vascular anastomosis in liver transplantation is significant for adequate liver graft perfusion, good postoperative graft function and overall outcome of the liver transplantation.

  2. Ultrasound detection of nonpalpable mammographically occult malignancy

    International Nuclear Information System (INIS)

    To evaluate the prevalence of occult malignancy with screening breast ultrasound. All ultrasound-guided core needle breast biopsies performed between January 1, 1999, and June 30, 2001, were retrospectively reviewed. Lesions were identified during screening breast ultrasound in high-risk women with no mammographic or palpable abnormality in either breast, a unilateral mammographic or palpable abnormality in the contralateral breast, or a unilateral mammographic or palpable abnormality in a different quadrant of the same breast. All ultrasound-detected lesions were histologically verified. Six hundred and fifty-two women with a mean age of 49 years underwent 698 biopsies during the study period. Three hundred and forty-nine of these lesions were detected at screening breast ultrasound. Out of 349, 11 (3.2%) had a mammographically and clinically occult malignancy. Nine cancers were found in women with no mammographic or palpable abnormality. Two cancers were found in the same breast as the mammographic or palpable abnormality. None were found in the breast contralateral to a palpable or mammographic abnormality. Screening breast ultrasound of high-risk women has a similar detection rate for occult carcinoma as screening mammography, but has a low positive predictive value in cases where biopsy is performed. (author)

  3. OCCULT-ORSER complete conversational user-language translator

    Science.gov (United States)

    Ramapriyan, H. K.; Young, K.

    1981-01-01

    Translator program (OCCULT) assists non-computer-oriented users in setting up and submitting jobs for complex ORSER system. ORSER is collection of image processing programs for analyzing remotely sensed data. OCCULT is designed for those who would like to use ORSER but cannot justify acquiring and maintaining necessary proficiency in Remote Job Entry Language, Job Control Language, and control-card formats. OCCULT is written in FORTRAN IV and OS Assembler for interactive execution.

  4. What can the Occult do for you? STarlight Attenuation & Reddening Survey of Multiple Occulting Galaxies (STARSMOG)

    CERN Document Server

    Holwerda, B W

    2015-01-01

    Interstellar dust is still the dominant uncertainty in Astronomy, limiting precision in e.g., cosmological distance estimates and models of how light is re-processed within a galaxy. When a foreground galaxy serendipitously overlaps a more distant one, the latter backlights the dusty structures in the nearer foreground galaxy. Such an overlapping or occulting galaxy pair can be used to measure the distribution of dust in the closest galaxy with great accuracy. The STARSMOG program uses HST observation of occulting galaxy pairs to accurately map the distribution of dust in foreground galaxies in fine ($<$100 pc) detail. Furthermore, Integral Field Unit observations of such pairs will map the effective extinction curve in these occulting galaxies, disentangling the role of fine-scale geometry and grain composition on the path of light through a galaxy. The overlapping galaxy technique promises to deliver a clear understanding of the dust in galaxies: the dust geometry, a probability function of the amount of...

  5. The subtype of VSD and the angiographic differentiation

    International Nuclear Information System (INIS)

    VSD is the most common congenital cardiac malformation and the natural history depends not only on the age of patients and the size of defect but the subtype of VSD as well, important factor in clinical management of those patients. In 110 patients, with surgically repaired VSD in Yonsei Medical Center in 1984, the subtype of VSDs evaluated by surgical observation were correlated with LV angiogram findings to verify the incidence of subtype in Korean and the diagnostic accuracy to predict the subtype by angiogram. 1. 110 patients included 64 boys and 46 girls, the age ranged from 3 months to 14 years (average 4.6 years old). 2. Angiographic findings were interpreted as follows; a. Perimembranous defects were profiled in LAO 60 .deg. LV angiogram and located below the aortic valve. In inlet excavation the shunted blood opacified the recess between septal leaflet of tricuspid valve and interventricular septum in early phase, in infundibular excavation opacified the recess between anterior leaflet of TV and anterior free wall of RV and in trabecular excavation the shunted blood traversed anterior portion of TV ring, opacified trabecular portion of RV cavity. b. Subarterial types were profiled in RAO 30 .deg. LV angiogram, just below aortic valve as well as pulmonic valve. Total infundibular defects were profiled in RAO 30 .deg. and LAO 60 .deg. LV angiogram subaortic in location in both views. c. In muscular VSD the profiled angle was varied according to the subtype but the defects were separated from the aortic valve as muscular septum interposed between the aortic valve and the defect. 3. The incidence of subtype of VSDs evaluated by surgical observation were as follows. Subarterial type : 32 cases (29.1%) Total infundibular defect : 5 cases (4.5%) Perimembranous type : 73 cases (66.3%) Infundibular excavation : 32 cases (29.2%) Trabecular excavation : 28 cases (25.5%) Inlet excavation : 10 cases (9.1%) Mixed : 3 cases (2.7%) Muscular type : 1 cases (0.9%) Total 63

  6. Arteriovenous fistulas of the anterior spinal artery mimicking other types of vascular malformations of the spinal cord

    International Nuclear Information System (INIS)

    Extramedullary direct arteriovenous (AV) fistulas of the anterior spinal artery are a rare type of vascular malformation of the spinal cord. This paper compares the angiographic appearance and flow dynamics of four atypical direct AV fistulas with the findings in 21 with a more classic appearance (I-III). Three of the direct AV fistulas had an angiographic appearance mimicking an intramedullary AV malformation, and one mimicked a dural AV fistula with medullar venous drainage. These four cases demonstrated direct AV fistulas of the anterior spinal artery whose tortuous arterial or venous collaterals observed the true nature of the single fistular type of lesion

  7. Ipsilateral occult hernias during endoscopic groin hernia repair

    Directory of Open Access Journals (Sweden)

    Jain Mayank

    2008-01-01

    Full Text Available Endoscopic repair of groin hernias allows the surgeon to have a complete view of the groin and pelvis to diagnose occult hernias both ipsilaterally and contralaterally. These occult hernias can then be treated simultaneously and may reduce the incidence of recurrence and persistent symptoms. The authors present four unusual cases where occult hernias were found ipsilaterally during an endoscopic repair. All these occult hernias were treated along with the clinically diagnosed hernia at the same surgery with excellent results and no post-operative morbidity.

  8. "Subarachnoid Hemorrhage; An An-giographic Evaluation in Iran "

    Directory of Open Access Journals (Sweden)

    K. Firouznia

    2004-06-01

    Full Text Available Background/Objectives: The evaluation of different aspects of subarachnoid hemorrhage (SAH can effectively improve the outcomes of this fatal disease. This article presents some information about angiographic and epidemiologic findings in 580 cases of SAH in Iran. Materials and Methods: We reviewed the records of 580 SAH patients in whom the disease was proved by brain CT scan and/or lumbar puncture. In all of the patients, a standard subtraction brain angiography was done. Results: Sixty percent of all patients were male and about sixty percent of patients were aged 30-60years. The angiogram showed: aneurysm in 23.4%, arteriovenous malformation in 14.1%, and miscellaneous problems in 6.3%. The angiogram was normal in the remained 56%. The mean age of aneurysm patients was 46 years, and 59% of them were male. 33.6% of aneurysms resided in A.C.A, 31% in I.C.A (14.1% of total aneurysms located in P.Comm.A, 24.8% in MCA and 10.7% of aneurysm were located in posterior circulation. Conclusion: The high prevalence of the disease in men could be due to the relatively high exposure of men to certain risk factors, such as smoking, or the ethnic factors may play a role. The lower mean age could be due to high percentage of men. Low prevalence of P.Comm.A aneurysms could be due to ethnic factors.

  9. Percutaneous vertebroplasty with a high-quality rotational angiographic unit

    Energy Technology Data Exchange (ETDEWEB)

    Pedicelli, Alessandro [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: apedicelli@rm.unicatt.it; Rollo, Massimo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mrollo@rm.unicatt.it; Piano, Mariangela [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mariangela.piano@gmail.com; Re, Thomas J. [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: tomjre@gmail.com; Cipriani, Maria C. [Department of Gerontology, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: alexped@yahoo.com; Colosimo, Cesare [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: colosimo@rm.unicatt.it; Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: lbonomo@rm.unicatt.it

    2009-02-15

    We evaluated the reliability of a rotational angiographic unit (RA) with flat-panel detector as a single technique to guide percutaneous vertebroplasty (PVP) and for post-procedure assessment by 2D and 3D reformatted images. Fifty-five consecutive patients (104 vertebral bodies) were treated under RA fluoroscopy. Rotational acquisitions with 2D and 3D reconstruction were obtained in all patients for immediate post-procedure assessment. In complex cases, this technique was also used to evaluate the needle position during the procedure. All patients underwent CT scan after the procedure. RA and CT findings were compared. In all cases, a safe trans-pedicular access and an accurate control of the bone-cement injection were successfully performed with high-quality fluoroscopy, even at the thoracic levels and in case of vertebra plana. 2D and 3D rotational reconstructions permitted CT-like images that clearly showed needle position and were similar to CT findings in depicting intrasomatic implant-distribution. RA detected 40 cement leakages compared to 42 demonstrated by CT and showed overall 95% sensitivity and 100% specificity compared to CT for final post-procedure assessment. Our preliminary results suggest that high-quality RA is reliable and safe as a single technique for PVP guidance, control and post-procedure assessment. It permits fast and cost-effective procedures avoiding multi-modality imaging.

  10. Major lower intestinal haemorrhage: angiographic localisation and current management

    International Nuclear Information System (INIS)

    Thirty-four patients with major lower intestinal bleeding underwent emergency selective mesenteric angiography during a 6-year period. Angiography identified a bleeding site in 16 patients (47%). Diverticulosis, found in 22 patients (65%), and angiodysplasia, found in 4 (12%), were the most common causes of major colonic bleeding and originated more frequently from the right colon. Eight patients (24%) bled from less common sources. Radiological control of bleeding was unreliable with a significant complication rate. Fourteen of 16 patients with positive angiograms and 6 of 18 patients with negative angiograms required surgery for persistent major bleeding. Angiographic localisation of colonic bleeding allowed limited resection in 9 of 11 patients with control of haemorrhage in 8 (89%). Fourteen of 34 patients were managed non-operatively; of these 2 had minor recurrent bleeding. The overall mortality rate was 29%, the operative mortality rate 40% and the non-operative mortality rate 14%. A rational diagnostic approach is presented, emphasising the role of selective mesenteric angiography in the management and surgical strategy of major lower intestinal bleeding

  11. Percutaneous vertebroplasty with a high-quality rotational angiographic unit

    International Nuclear Information System (INIS)

    We evaluated the reliability of a rotational angiographic unit (RA) with flat-panel detector as a single technique to guide percutaneous vertebroplasty (PVP) and for post-procedure assessment by 2D and 3D reformatted images. Fifty-five consecutive patients (104 vertebral bodies) were treated under RA fluoroscopy. Rotational acquisitions with 2D and 3D reconstruction were obtained in all patients for immediate post-procedure assessment. In complex cases, this technique was also used to evaluate the needle position during the procedure. All patients underwent CT scan after the procedure. RA and CT findings were compared. In all cases, a safe trans-pedicular access and an accurate control of the bone-cement injection were successfully performed with high-quality fluoroscopy, even at the thoracic levels and in case of vertebra plana. 2D and 3D rotational reconstructions permitted CT-like images that clearly showed needle position and were similar to CT findings in depicting intrasomatic implant-distribution. RA detected 40 cement leakages compared to 42 demonstrated by CT and showed overall 95% sensitivity and 100% specificity compared to CT for final post-procedure assessment. Our preliminary results suggest that high-quality RA is reliable and safe as a single technique for PVP guidance, control and post-procedure assessment. It permits fast and cost-effective procedures avoiding multi-modality imaging

  12. New perspectives in occult hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Vicente Carre(n)o; Javier Bartolomé; Inmaculada Castillo; Juan Antonio Quiroga

    2012-01-01

    Occult hepatitis C virus (HCV) infection,defined as the presence of HCV RNA in liver and in peripheral blood mononuclear cells (PBMCs) in the absence of detectable viral RNA in serum by standard assays,can be found in anti-HCV positive patients with normal serum levels of liver enzymes and in anti-HCV negative patients with persistently elevated liver enzymes of unknown etiology.Occult HCV infection is distributed worldwide and all HCV genotypes seem to be involved in this infection.Occult hepatitis C has been found not only in anti-HCV positive subjects with normal values of liver enzymes or in chronic hepatitis of unknown origin but also in several groups at risk for HCV infection such as hemodialysis patients or family members of patients with occult HCV.This occult infection has been reported also in healthy populations without evidence of liver disease.Occult HCV infection seems to be less aggressive than chronic hepatitis C although patients affected by occult HCV may develop liver cirrhosis and even hepatocellular carcinoma.Thus,anti-HCV negative patients with occult HCV may benefit from antiviral therapy with pegylatedinterferon plus ribavirin.The persistence of very low levels of HCV RNA in serum and in PBMCs,along with the maintenance of specific T-cell responses against HCV-antigens observed during a long-term follow-up of patients with occult hepatitis C,indicate that occult HCV is a persistent infection that is not spontaneously eradicated.This is an updated report on diagnosis,epidemiology and clinical implications of occult HCV with special emphasis on anti-HCV negative cases.

  13. Data analysis of 2005 Regulus occultation and simulation of the 2014 occultation

    CERN Document Server

    Sigismondi, Costantino; Flatrès, Thomas

    2014-01-01

    On March 20, 2014 at 6:06 UT (2:06 New York time) Regulus, the 1.3 magnitude brighter star of Leo constellation, is going to be occulted by the asteroid 163 Erigone. The unusual event, visible to the naked eye over NYC, can allow to measure the shape of the asteroid, with reaching a space resolution below the diffraction limit of the eye, and of all instruments not based on interferometry. Ultimately the aperture of the instrument is related to the amount of scintillation affecting the light curve of the occultation, limitating the accuracy of video recorded data. The asteroid profile scans the surface of the star at a velocity of 6 mas/s; the diameter of the star is about 1.3 mas and the detection of the stellar limb darkening signature is discussed, taking into consideration also the Fresnel fringes. New data reduction with R-OTE software of the 2005 Regulus occultation and simulations of the 2014 occultation with Fren_difl software are presented.

  14. The Treatment of the Occult in General Encyclopedias.

    Science.gov (United States)

    Sonnenfeld, Gary F.

    This paper is a content analysis of three general encyclopedias, "Encyclopedia Americana" (EA), "Encyclopaedia Brittanica" (EB), and "World Book Encyclopedia" (WBC), which quantifies the treatment of the occult. Entries are selected from each by starting with the article "Occultism" and tracing all cross-references. Cross-references are likewise…

  15. Occult HCV in Egyptian volunteer blood donors

    Directory of Open Access Journals (Sweden)

    Mostafa A. Amin 1, Kouka S. E. Abdel-Wahab 2 and Adel A.

    2013-01-01

    Full Text Available Objective: The study aims to investigate the risk of post-transfusion transmission of hepatitis c virus (HCV in the circumstances of occult HCV when anti-HCV is undetectable by ELISA and HCV-RNA is detected by RT-PCR in the plasma and or in peripheral blood mononuclear cells (PBMCs of donor blood and the recipients are immunocompromised. Patients & methods: The study covered 18 chronic renal failure patients (CRF [12 males (66.7% their age ranged from 28 to 65 years and 6 females (33.3 % their age ranged from 15 to 55 years] undergoing hemodialysis in Nile Hospital as part of their therapy have to receive blood transfusions (275 blood units for the first time. Commercial ELISA kits for anti-HCV and nested-RT-PCR (N-RT-PCR kits were used. Results: Anti-HCV was positive in one serum from the eighteen (5.5% poly transfused CRF patients at the end of the study while the seventeen sera were negative. This serum was also positive for HCV RNA by N-RT-PCR. Out of the 20 transfused blood units, one blood unit (three components were tested by blood banking anti-HCV negative by ELISA, were positive for HCV RNA by N-RT-PCR. The collective markers of this blood unit represent an occult HCV. The risk of acquiring post-transfusion HCV infection from an occult HCV blood unit is 5%. Real time PCR showed variation in the viral load of the serum of the infected CRF patient, the plasma of blood unit, the PBMCs of this blood unit whether activated by PHA-M or not.

  16. 3D multidetector CT angiographic evaluation of intralobular bronchopulmonary sequestration

    Directory of Open Access Journals (Sweden)

    Marwah Ruchira

    2010-01-01

    Full Text Available We report a case of intralobar pulmonary sequestration with special emphasis on computed tomography (CT angiography in determining the arterial supply and venous drainage, thus providing a detailed knowledge of the vasculature, which is of vital importance in surgery. The 3D volume rendering technique and maximum intensity projection images provide the vascular road map for the surgeon.

  17. Prevalence of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Maria Luisa Gutiérrez-García; Conrado M Fernandez-Rodriguez; Jose Luis Lledo-Navarro; Ingrid Buhigas-Garcia

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen. The prevalence of OBI is quite variable depending on the level of endemic disease in different parts of the world,the different assays utilized in the studies, and the different populations studied. Many studies have been carried out on OBI prevalence in different areas of the world and categories of individuals. The studies show that OBI prevalence seems to be higher among subjects at high risk for HBV infection and with liver disease than among individuals at low risk of infection and without liver disease.

  18. Stationary occultations from low Earth orbit

    Science.gov (United States)

    Percival, Jeffrey W.

    1993-01-01

    The process of stationary lunar occultations is considered for observers in LEO. The orbit of the Hubble Space Telescope (HST) is used as a prototype. The noncoplanarity of the HST and lunar orbits disrupts many of the expected stationary events, and orbital drag complicates the prediction problem. In a typical year, the apparent speed of the lunar limb seen by the HST is slower than a typical ground-based event only about 0.7 percent of the time. The orbit prediction can be wrong by as much as 20 deg in 53 days, with most of the error lying in the plane of the orbit.

  19. Retrieval Algorithms for the Halogen Occultation Experiment

    Science.gov (United States)

    Thompson, Robert E.; Gordley, Larry L.

    2009-01-01

    The Halogen Occultation Experiment (HALOE) on the Upper Atmosphere Research Satellite (UARS) provided high quality measurements of key middle atmosphere constituents, aerosol characteristics, and temperature for 14 years (1991-2005). This report is an outline of the Level 2 retrieval algorithms, and it also describes the great care that was taken in characterizing the instrument prior to launch and throughout its mission life. It represents an historical record of the techniques used to analyze the data and of the steps that must be considered for the development of a similar experiment for future satellite missions.

  20. The normal internal carotid artery: a computed tomography angiographic study

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, Suvi Maaria; Valanne, Leena; Silvennoinen, Heli [Helsinki University Central Hospital and University of Helsinki, Department of Radiology, HUS Medical Imaging Center, Helsinki (Finland); Soinne, Lauri [Helsinki University Central Hospital, Department of Neurology, Helsinki (Finland)

    2014-09-15

    Systematic computed tomography angiographic (CTA) studies investigating variation in internal carotid artery (ICA) luminal diameters (LDs) are scarce. Knowledge of the normal intra-individual LD variability would provide a cut-off value for detection of more subtle collapses. In addition, low intra-individual variability would allow using contralateral LD as a reference for estimation of stenosis degree in cases where ipsilateral measurement is hampered. Therefore, our aim was to investigate intra-individual LD variation of normal ICA. We retrospectively collected multidetector high-speed CTAs of 104 patients younger than 40 years who were considered not to have carotid pathology. We carried out independent measurements of the common carotid artery (CCA) and ICA LDs bilaterally from axial source images by two observers, analysing side-to-side LD differences from averaged double measurements with a paired t test. We discovered no significant side-to-side LD differences. In the female group, the mean differences (mm) with 95 % confidence intervals were 0.08 (0.00, 0.17) for CCA and 0.03 (-0.04, 0.11) for ICA, with ICA LD standard deviation of 0.4 mm. In the male group, these were: 0.06 (-0.04, 0.17), 0.02 (-0.07, 0.11) and 0.4 mm, respectively. We detected no ICA agenesis. The intrinsic intra-individual variation of the LD of normal ICA is minimal. This uniformity may serve as the basis for detection of subtle grades of side-to-side variation caused by pathology. (orig.)

  1. ANGIOGRAPHIC PROFILE OF LEFT MAIN CORONARY ARTERY (LMCA STENOSIS

    Directory of Open Access Journals (Sweden)

    Malladi Srinivasa

    2015-02-01

    Full Text Available Among patients with coronary artery disease, left coronary artery (LMCA stenosis is the dangerous form of coronary arterial involvement, associated with increased mortality and morbidity unless immediate intervention is done. The gold standard treatment for left main coronary artery (LMCA stenosis is the emergency coronary artery bypass grafting to its branches, left anterior descending artery (LAD, and left circumflex artery (LCX. Of percutaneous intervention in the form of angioplasty and stenting of left main coronary artery are increasingly done. The anatomy and the site of stenosi s in the left main coronary artery determine the management option. In this context, the involvement of left main coronary artery and its anatomical pattern are important in deciding management options. AIM: To study the angiographic profile of significant Left main coronary artery (LMCA stenosis among the patients who underwent coronary angiography. METHODS: A total of 1911 cases of significant coronary arterial disease, who underwent coronary angiography a t King George Hospital, Visakhapatnam were studied in the present study and their coronary angiograms were analysed with respect to the pattern of involvement. RESULTS: of the 1911 cases of coronary artery disease, 118 patients have left main coronary arte ry disease. M/F ratio is 93/25. Of them 68.4% are hypertensive, 41.5 % are diabetics, 34.7% are smokers. Mean age of presentation was 59 yrs. Isolated LMCA involvement is seen in 5, associated with single vessel disease in 9, double vessel disease in 12 an d triple vessel diseases in 93. Ostio - proximal involvement is seen in 21, mid segment involvement in 13, distal – bifurcation involvement in 93 and total occlusion of LMCA in 1 case. CONCLUSION: Significant LMCA involvement is seen in 6.1%. In majority of c ases, it is associated with triple vessel disease and distal bifurcation is the commonest site involved.

  2. What Is Vascular Disease?

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  3. Diabetes and Vascular Disease

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  4. A digital video system for observing and recording occultations

    CERN Document Server

    Barry, M A; Pavlov, Hristo; Hanna, William; McEwan, Alistair; Filipovic, Miroslav

    2015-01-01

    Stellar occultations by asteroids and outer solar system bodies can offer ground based observers with modest telescopes and camera equipment the opportunity to probe the shape, size, atmosphere and attendant moons or rings of these distant objects. The essential requirements of the camera and recording equipment are: good quantum efficiency and low noise, minimal dead time between images, good horological faithfulness of the image time stamps, robustness of the recording to unexpected failure, and low cost. We describe the Astronomical Digital Video occultation observing and recording System (ADVS) which attempts to fulfil these requirements and compare the system with other reported camera and recorder systems. Five systems have been built, deployed and tested over the past three years, and we report on three representative occultation observations: one being a 9 +/-1.5 second occultation of the trans-Neptunian object 28978 Ixion (mv=15.2) at 3 seconds per frame, one being a 1.51 +/-0.017 second occultation ...

  5. Radio occultation experiments with INAF-IRA radiotelescopes.

    Science.gov (United States)

    Pluchino, S.; Schillirò, F.; Salerno, E.; Pupillo, G.

    The Radio Occultation research program performed at the Medicina and Noto Radioastronomical Stations of the Istituto Nazionale di Astrofisica (INAF) - Istituto di Radioastronomia (IRA) includes observations of spacecraft by satellite and satellite by satellite events. The Lunar Radio Occultation (LRO) part of the program consists in collecting data of the lunar Total Electron Content (TEC), at different limb longitudes and at different time, in order to study long term variation of the Moon's ionosphere. The LRO program started at Medicina in September 2006 with the observation of the European probe SMART-1 during its impact on the lunar soil. It proceeded in 2007 with the observation of the lunar occultations of Saturn and Venus, and with the observation of Mars in 2008. On this occasion the probes Cassini, Venus Express, Mars Express, Mars Reconaissance Orbiter and Mars Odissey were respectively occulted by the moon. On Dec 1st 2008 a Venus lunar occultation occurred. On that occasion we performed the first Italian-VLBI (I-VLBI) tracking experiment by detecting the carrier signals coming from the Venus Express (VEX) spacecraft with both the IRA radiotelescopes together with the Matera antenna of the Italian Space Agency. The second part of the radio occultation program includes the observation of satellite by satellite occultation events, as well as mutual occultations of Jupiter satellites. These events are referred to as mutual phenomena (PHEMU). These observations are aimed to measure the radio flux variation during the occultation and to derive surface spatial characteristics such as Io's hot spots. In this work preliminary results of the Radio Occultation program will be presented.

  6. Occult choriocarcinoma: Detection using radiolabeled monoclonal antibodies

    International Nuclear Information System (INIS)

    Occult choriocarcinoma, manifested only by an elevated B-hCG level, can be a difficult management problem. The authors evaluated the ability of I-131-labeled 5F9.3, a murine monoclonal antibody reactive with choriocarcinomas but not hCG, to detect foci of choriocarcinoma in five patients referred with elevated B-hCG levels but in whom the location of residual disease was uncertain. I-131 5F9.3, 0.5-1.0 mCi, was injected intravenously in each patient and images with dynamic background subtraction of TcHSA were obtained at later time points. In four patients chest studies were true positive (confirmed surgically in all), the chest CT scans in these patients had been interpreted as not definitely showing active disease. In the fifth patient no abnormal focus of uptake was seen and subsequent B-hCG levels normalized. In two of the patients with chest lesions, foci of abdominal uptake were seen that were not due to tumor. One of these patients had a partial small bowel obstruction; the other appeared to have a false-positive study. I-131 5F9.3 is a promising agent for the detection of occult choriocarcinomas

  7. Evaluation of occult fracture around the knee

    International Nuclear Information System (INIS)

    Injuries in the vicinity of the knee joint are often seen in daily medical care. Occult fractures are fractures which do not show up on roentgenograms in the first examination, but in follow-up examinations. In this study, we investigated 60 cases of occult fractures around the knee joint treated at our department which did not appear in initial roentgenograms. Their ages ranged from 15 to 96 years old, with a mean age of 71.5 years old. They consisted of eight men and 52 females. Fifty-nine cases were diagnosed by MRI. All samples were treated by conservative management. At week 8 from the first examination, symptoms were found to have disappeared in 82.1%. Fractures tend to occur easily in elderly women. More than 75% are caused by moderate external force, suggesting relation with osteoporosis. When elderly women fall, if swelling of the knee joint and hemarthrosis are seen, fractures should be suspected even if they do not appear on X-ray, and MRI should be useful for such diagnosis. (author)

  8. Processing GPS Occultation Data To Characterize Atmosphere

    Science.gov (United States)

    Hajj, George; Kursinski, Emil; Leroy, Stephen; Lijima, Byron; de la Torre Juarez, Manuel; Romans, Larry; Ao, Chi

    2005-01-01

    GOAS [Global Positioning System (GPS) Occultation Analysis System] is a computer program that accepts signal-occultation data from GPS receivers aboard low-Earth-orbiting satellites and processes the data to characterize the terrestrial atmosphere and, in somewhat less comprehensive fashion, the ionosphere. GOAS is very robust and can be run in an unattended semi-operational processing mode. It features sophisticated retrieval algorithms that utilize the amplitudes and phases of the GPS signals. It incorporates a module that, using an assumed atmospheric refractivity profile, simulates the effects of the retrieval processing system, including the GPS receiver. GOAS utilizes the GIPSY software for precise determination of orbits as needed for calibration. The GOAS output for the Earth s troposphere and mid-to-lower stratosphere consists of high-resolution (<1 km) profiles of density, temperature, pressure, atmospheric refractivity, bending angles of signals, and water-vapor content versus altitude from the Earth s surface to an altitude of 30 km. The GOAS output for the ionosphere consists of electron-density profiles from an altitude of about 50 km to the altitude of a satellite, plus parameters related to the rapidly varying structure of the electron density, particularly in the E layer of the ionosphere.

  9. A Digital Video System for Observing and Recording Occultations

    Science.gov (United States)

    Barry, M. A. Tony; Gault, Dave; Pavlov, Hristo; Hanna, William; McEwan, Alistair; Filipović, Miroslav D.

    2015-09-01

    Stellar occultations by asteroids and outer solar system bodies can offer ground based observers with modest telescopes and camera equipment the opportunity to probe the shape, size, atmosphere, and attendant moons or rings of these distant objects. The essential requirements of the camera and recording equipment are: good quantum efficiency and low noise; minimal dead time between images; good horological faithfulness of the image timestamps; robustness of the recording to unexpected failure; and low cost. We describe an occultation observing and recording system which attempts to fulfil these requirements and compare the system with other reported camera and recorder systems. Five systems have been built, deployed, and tested over the past three years, and we report on three representative occultation observations: one being a 9 ± 1.5 s occultation of the trans-Neptunian object 28978 Ixion (m v =15.2) at 3 seconds per frame; one being a 1.51 ± 0.017 s occultation of Deimos, the 12 km diameter satellite of Mars, at 30 frames per second; and one being a 11.04 ± 0.4 s occultation, recorded at 7.5 frames per second, of the main belt asteroid 361 Havnia, representing a low magnitude drop (Δm v = ~0.4) occultation.

  10. Asteroid occultations today and tomorrow: toward the GAIA era

    Science.gov (United States)

    Tanga, P.; Delbo, M.

    2007-11-01

    Context: Observation of star occultations is a powerful tool to determine shapes and sizes of asteroids. This is key information necessary for studying the evolution of the asteroid belt and to calibrate indirect methods of size determination, such as the models used to analyze thermal infrared observations. Up to now, the observation of asteroid occultations is an activity essentially secured by amateur astronomers equipped with small, portable equipments. However, the accuracy of the available ephemeris prevents accurate predictions of the occultation events for objects smaller than ~100 km. Aims: We investigate current limits in predictability and observability of asteroid occultations, and we study their possible evolution in the future, when high accuracy asteroid orbits and star positions (such as those expected from the mission Gaia of the European Space Agency) will be available. Methods: We use a simple model for asteroid ephemeris uncertainties and numerical algorithms for estimating the limits imposed by the instruments, assuming realistic CCD performances and asteroid size distribution, to estimate the expected occultation rate under different conditions. Results: We show that high accuracy ephemerides which will be available in the future will extend toward much smaller asteroids the possibility of observing asteroid occultations, greatly increasing the number of events and objects involved. A complete set of size measurements down to ~10 km main belt asteroids could be obtained in a few years, provided that a small network of ground-based 1m telescopes are devoted to occultation studies.

  11. The occultation of Kappa Geminorum by Eros. [stellar occultation observed for asteroid size and shape

    Science.gov (United States)

    Oleary, B.; Marsden, B. G.; Dragon, R.; Hauser, E.; Mcgrath, M.; Backus, P.; Robkoff, H.

    1976-01-01

    The paper discusses predictions and observations of the occultation of Kappa Gem by (433) Eros on January 24, 1975. Several positive and negative observations made in western New England are described. Local circumstances for the occultation are reconstructed, and the size and shape of Eros are determined analytically as well as graphically. The calculations yield two extremes for the cross section: a circle 23 km in diameter or a somewhat irregular figure 20 km by 6 or 7 km. Arguments based on the expected albedo of the asteroid suggest that the circle should be warped into an ellipse 21 by 13 km or that the irregular figure might be one component of a dumbbell-like profile.

  12. Flight System Implementation of the Spacecraft Occulter System for Theia

    Science.gov (United States)

    Tenerelli, Domenick; Theia

    2009-01-01

    The objective of the Theia program is to characterize Earth-like planets around nearby stars. Theia utilizes two formation-flying spacecraft in an L2 orbit - an observatory and a free flying occulter. Characterization involves looking for signs of life by observing molecular signatures and the presence of water vapor. A free flying occulter spacecraft provides starlight suppression by blocking the starlight while allowing planet light to pass. A diffraction limited monolithic optical telescope is provided for observing planet light passed by the occulter spacecraft. The occulter spacecraft and observatory are flown with a separation of 38, 700 km to 72,000 km (depending on telescope aperture). The Theia system design greatly simplifies design, manufacturing, modeling, and testing requirements compared to a stand-alone high performance internal coronagraph. Design advantages include having thermal/mechanical specifications approaching those of a conventional telescope requiring minimal actuator count. Standard materials and manufacturing approaches apply. End-to-end testing and facilities requirements are standard. The occulter is comprised of up to 30 petals constructed of a dimensionally stable material. Each petal is structurally reinforced for ground handling and testing purposes. An electro-mechanically actuated deployment utilizes standard space qualified mechanism designs to achieve up to a 50m deployed diameter. Multiple layers ensure performance over 5 years of micro-meteroid degradation. The occulter spacecraft is a modular design built of dimensionally stable composite material with 6 bays mounted to a propulsion sub-assembly. The occulter spacecraft uses ion thrusters to achieve its required delta-V over its lifetime and to maintain a position tolerance of 1 m with respect to the observatory. A traditional reaction wheel system is used to maintain orientation. The occulter and occulter spacecraft are compatible with the Atlas 5 launch vehicle.

  13. Cerebral angiographic changes on serial examination of a patient with migraine

    International Nuclear Information System (INIS)

    Curious cerebral angiographic changes are described in a 27-year-old female migraine patient. During the period of observation of this patient, both the intracranial carotid artery and the vertebrobasilar artery systems presented unusual and fascinating cerebral arteriographic pictures. In an attack of migraine, angiography showed that all the intracranial secondary and tertiary branches of the carotid arterial system were dilated without showing any changes in the extracranial arteries and when the migraine attack had subsided, all branches of the carotid arteries as well as the vertebrobasilar arteries demonstreated abnormal segmental narrowings or vasospasm. These sequential angiographic changes have not been hitherto reported in migraine. (orig.)

  14. Angiographic findings after supplementation with Heracleum persicum extract: Results of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Yunes Panahi

    2015-01-01

    Full Text Available Background: Heracleum persicum is a common dietary spice with several traditional medicinal properties important for cardiovascular health including antioxidant, hypolipidemic, and anti-inflammatory effects. This study explored the effects of supplementation with H. persicum fruit on the angiographic findings of patients with minimal coronary artery disease (CAD. Methods: Subjects who were diagnosed with 0.05. Similarly, there was no significant difference between the study groups in terms of disease progression and chest pain score (P > 0.05. Conclusions: The present results do not support any clinically significant benefit of supplementation with H. persicum extract on the angiographic findings of in patients with minimal CAD.

  15. Angiographic evaluation of the response to neoadjuvant chemotherapy in osteogenic sarcoma

    International Nuclear Information System (INIS)

    Modern therapeutic osteosarcoma protocols, including both pre- and post-operative cycles of chemotherapy, have helped improving the quality of the prognosis and marking the local control of the neoplasm more reliable, with a subsequent increase in conservative surgery. Angiographic results of the chemotherapeutic response in 76 patients with primitive high-grade bone to repeat angiographic controls under the same technical conditions is emphasized. The comparison of above findings with data from the histological evaluation of the specimen, shows that angiography is a reliable means of evaluating the response to chemiotherapy. Angiography is thus emphasized as a valid method in an early evaluation of the efficacy of chemiotherapy

  16. The Research and Education Collaborative Occultation Network: A System for Coordinated TNO Occultation Observations

    Science.gov (United States)

    Buie, Marc W.; Keller, John M.

    2016-03-01

    We describe a new system and method for collecting coordinated occultation observations of trans-Neptunian objects (TNOs). Occultations by objects in the outer solar system are more difficult to predict due to their large distance and limited span of the astrometric data used to determine their orbits and positions. This project brings together the research and educational community into a unique citizen-science partnership to overcome the difficulties of observing these distant objects. The goal of the project is to get sizes and shapes for TNOs with diameters larger than 100 km. As a result of the system design it will also serve as a probe for binary systems with spatial separations as small as contact systems. Traditional occultation efforts strive to get a prediction sufficiently good to place mobile ground stations in the shadow track. Our system takes a new approach of setting up a large number of fixed observing stations and letting the shadows come to the network. The nominal spacing of the stations is 50 km so that we ensure two chords at our limiting size. The spread of the network is roughly 2000 km along a roughly north-south line in the western United States. The network contains 56 stations that are committed to the project and we get additional ad hoc support from International Occultation Timing Association members. At our minimum size, two stations will record an event while the other stations will be probing the inner regions for secondary events. Larger objects will get more chords and will allow determination of shape profiles. The stations are almost exclusively sited and associated with schools, usually at the 9-12 grade level. We present a full description of the system we have developed for the continued exploration of the Kuiper Belt.

  17. The stellar occultation by Makemake on 2011 April 23

    OpenAIRE

    Ortiz, J. L.; Sicardy, B.; Assafin, M.; Alvarez-Candal, A; Ivanov, V. D.; Camargo, J; Littlefair, S.; Unda-Sanzana, E.; Jehin, Emmanuel; Braga-Ribas, F.; Lellouch, E.; Morales, N.; Licandro, J.; Gil-Hutton, R.; Duffard, R.

    2011-01-01

    We have taken advantage of a stellar occultation by the dwarf planet Makemake on 2011 April 23, to determine several of its main physical properties. We present results from a multisite campaign with 8 positive occultation detections from 5 different sites, including data from the 8-m VLT and 3.5-m NTT telescopes in Chile, which have very high temporal resolution. Because the star was significantly fainter than Makemake (setting a record in the magnitude of a star whose occultation has been d...

  18. CT detection of occult pneumothorax in head trauma

    International Nuclear Information System (INIS)

    A prospective evaluation for occult pneumothorax was performed in 25 consecutive patients with serious head trauma by combining a limited chest CT examination with the emergency head CT examination. Of 21 pneuomothoraces present in 15 patients, 11 (52%) were found only by chest CT and were not identified clinically or by supine chest radiograph. Because of pending therapeutic measures, chest tubes were placed in nine of the 11 occult pneumothoraces, regardless of the volume. Chest CT proved itself as the most sensitive method for detection of occult pneumothorax, permitting early chest tube placement to prevent transition to a tension pneumothorax during subsequent mechanical ventilation or emergency surgery under general anesthesia

  19. The Uranus Occultation of 10 June 1979. I. The Rings

    OpenAIRE

    Nicholson, P. D.; Matthews, K; Goldreich, P.

    1981-01-01

    Observations and analysis of a stellar occultation by the rings of Uranus on 10 June 1979 are presented. Occultations by rings 4, ɑ, β, y, δ, and є are identified, and radii and azimuths of the occulting segments in the plane of the rings calculated. Results for rings y and δ are consistent with the hypothesis (Elliot et al. 1978; Nicholson et ɑl. 1978) that these two rings are circular and coplanar, and an approximate upper limit of 8 X 10^(-5) is placed on the eccentricity of either ring...

  20. Asteroid Shape Models Refined By Stellar Occultation Silhouettes

    Science.gov (United States)

    Durech, J.; Kaasalainen, M.

    2004-12-01

    We present shape models of asteroids 2 Pallas, 3 Juno, 39 Laetitia, 41 Daphne, 52 Europa, 85 Io, 129 Antigone, and 208 Lacrimosa derived from their lightcurves and stellar occultation silhouettes. Lightcurve inversion shape models and rotation states of those asteroids were already published. The occultation silhouettes give direct information about the size and shape of asteroid's projected cross-section. We process the lightcurve and occultation data simultaneously and derive more detailed shape models, remove possible ambiguities in the pole directions, and calibrate the models to absolute dimensions.

  1. Fecal Occult Blood Test and Gastrointestinal Parasitic Infection

    Directory of Open Access Journals (Sweden)

    Majed H. Wakid

    2010-01-01

    Full Text Available Stool specimens of 1238 workers in western region of Saudi Arabia were examined for infection with intestinal parasites and for fecal occult blood (FOB to investigate the possibility that enteroparasites correlate to occult intestinal bleeding. Direct smears and formal ether techniques were used for detection of diagnostic stages of intestinal parasites. A commercially available guaiac test was used to detect fecal occult blood. 47.01% of the workers were infected with intestinal parasites including eight helminthes species and eight protozoan species. The results provided no significant evidence (P-value=0.143 that intestinal parasitic infection is in association with positive guaiac FOB test.

  2. Calcification of the intracranial carotid artery and its relation to the clinical and angiographic picture: an angiographic classification of asteriosclerosis cerebri

    Directory of Open Access Journals (Sweden)

    Valter Seixas

    1968-03-01

    Full Text Available Fifty six patients with arteriosclerosis cerebri confirmed by X-rays examinations were clinically and angiographically studied. Calcifications of the carotid artery were found predominantly in human beings between the ages of 55 and 65 and more often among men than among women, the proportion being 2.5 to 1. Nearly all arteriosclerotic patients with calcium deposits in the carotid artery showed several neurological and mental deficits, the most frequent initial symptoms being motor disturbances. Angiographic anormalities found in these patients can be classed into 3 groups: (a grade I— wavy course of the cerebral vessels, small number of peripheral brain vessels, formation of small knots, prolonged circulation time, arteria cerebri anterior with angular form, straight course and broad caliber; (b grade II— partial block, irregularities of wall and caliber, aneurysmal formations; (c grade III— total block of some vessels of the carotid system preventing a generalized or localized cerebral blood supply. Grades II and III angiographic abnormalities were most often seen at the syphon and at the carotid bifurcation in the neck (site of predilection. Most patients with a progressive clinical course belonged to the I group. The course of the disease did not differ in patients with grades II and III angiographic changes since usually the illness had an apoplectiform onset. Arteriosclerotic degenerative irregularities within the layers of the arteries (up to atheromatous patches may occur without reducing the arterial lumen. In such cases the patients may remain asymptomatic until there is a decompensation in the brain circulation due to many causes.

  3. What can the occult do for you?

    CERN Document Server

    Holwerda, B W

    2016-01-01

    Interstellar dust is still a dominant uncertainty in Astronomy, limiting precision in e.g., cosmological distance estimates and models of how light is re-processed within a galaxy. When a foreground galaxy serendipitously overlaps a more distant one, the latter backlights the dusty structures in the nearer foreground galaxy. Such an overlapping or occulting galaxy pair can be used to measure the distribution of dust in the closest galaxy with great accuracy. The STARSMOG program uses Hubble to map the distribution of dust in foreground galaxies in fine (<100 pc) detail. Integral Field Unit (IFU) observations will map the effective extinction curve, disentangling the role of fine-scale geometry and grain composition on the path of light through a galaxy. The overlapping galaxy technique promises to deliver a clear understanding of the dust in galaxies: geometry, a probability function of dimming as a function of galaxy mass and radius, and its dependence on wavelength.

  4. Occult hepatitis B virus infection in Egypt

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The emerging evidence of the potentially clinicalimportance of occult hepatitis B virus (HBV) infection(OBI) increases the interest in this topic. OBI mayimpact in several clinical contexts, which include thepossible transmission of the infection, the contributionto liver disease progression, the development ofhepatocellular carcinoma, and the risk of reactivation.There are several articles that have published on OBI inEgyptian populations. A review of MEDLINE databasewas undertaken for relevant articles to clarify theepidemiology of OBI in Egypt. HBV genotype D is theonly detectable genotype among Egyptian OBI patients.Higher rates of OBI reported among Egyptian chronicHCV, hemodialysis, children with malignant disorders, andcryptogenic liver disease patients. There is an evidenceof OBI reactivation after treatment with chemotherapy.The available data suggested that screening for OBI mustbe a routine practice in these groups of patients. Furtherstudies needed for better understand of the epidemiologyof OBI among Egyptian young generations after the eraof hepatitis B vaccination.

  5. Magnetic Resonance Imaging in occult spinal dysraphism

    International Nuclear Information System (INIS)

    A prospective study was carried out in 100 cases of suspected occult spinal dysraphic anomalies with Magnetic Resonance Imaging (MRI) in order to determine its diagnostic efficacy as the initial imaging modality. MR imaging provided accurate preoperative information in 91 out of 92 cases (98.9%). Some of the unusual and interesting findings in the series were: presence of intrinsic cord abnormality in 19 out of 21 cases (90.4%) with a normal plain radiography, 4 cases of diastematomyelia with a dermoid in the dorsal and lumbar region associated with syringohydromyelia, intradural fibrous/glial bands, syringo-hydromyelia/myelomalacia of the conus with tethered cord syndrome having a normally paced conus, and myelocystocele. It is concluded that MRI is an excellent primary diagnostic tool, together with a plain radiography, for complete preoperative evaluation of mid-line spinal anomalies. 14 refs., 3 tabs., 7 figs

  6. Paraneoplastic retinopathy associated with occult bladder cancer

    Directory of Open Access Journals (Sweden)

    M Nivean

    2016-01-01

    Full Text Available The aim was to report the first case of cancer-associated retinopathy (CAR presenting before bladder cancer diagnosis. A 71-year-old woman with a history of bilateral vision loss underwent subsequent complete ophthalmic examination include a fluorescein angiography, full-field electroretinogram (ERG, serology including serum antibodies for CAR, and positron emission tomography-computed tomography (PET-CT scan. The patient was diagnosed with bladder carcinoma revealed by PET-CT. Timely recognition of this entity may be crucial for an increased patient survival thus adult onset progressive photoreceptor dysfunction, confirmed by ERG, should alert to a possible remote effect of known or occult malignancy. In the latter, PET-CT may be exploited as a powerful diagnostic tool.

  7. Paraneoplastic retinopathy associated with occult bladder cancer

    DEFF Research Database (Denmark)

    Nivean, M; Muttuvelu, Danson V; Afzelius, Pia Maria Tullia;

    2016-01-01

    The aim was to report the first case of cancer-associated retinopathy (CAR) presenting before bladder cancer diagnosis. A 71-year-old woman with a history of bilateral vision loss underwent subsequent complete ophthalmic examination include a fluorescein angiography, full-field electroretinogram...... (ERG), serology including serum antibodies for CAR, and positron emission tomography-computed tomography (PET-CT) scan. The patient was diagnosed with bladder carcinoma revealed by PET-CT. Timely recognition of this entity may be crucial for an increased patient survival thus adult onset progressive...... photoreceptor dysfunction, confirmed by ERG, should alert to a possible remote effect of known or occult malignancy. In the latter, PET-CT may be exploited as a powerful diagnostic tool....

  8. Verifying timestamps of occultation observation systems

    CERN Document Server

    A., M; Gault, Dave; Bolt, Greg; McEwan, Alistair; Filipovic, Miroslav D; White, Graeme L

    2015-01-01

    We describe an image timestamp verification system to determine the exposure timing characteristics and continuity of images made by an imaging camera and recorder, with reference to Coordinated Universal Time (UTC). The original use was to verify the timestamps of stellar occultation recording systems, but the system is applicable to lunar flashes, planetary transits, sprite recording, or any area where reliable timestamps are required. The system offers good temporal resolution (down to 2 msec, referred to UTC) and provides exposure duration and interframe dead time information. The system uses inexpensive, off-the- shelf components, requires minimal assembly and requires no high-voltage components or connections. We also describe an application to load FITS (and other format) image files, which can decode the verification image timestamp. Source code, wiring diagrams and built applications are provided to aid the construction and use of the device.

  9. Angiographic findings before and after transplantation of split myocutaneous flaps

    International Nuclear Information System (INIS)

    Prerequisite for successful split-skin flap transplants of myocutaneous flaps is the presence of adequate adjacent afferent and efferent vessels, thus making an arteriography of the receiving region mandatory during surgery preparation. In 20 or 29 patients in whom a split myocutaneous flap was transplanted to the lower leg, angiography revealed 22 pathological or other therapy-relevant findings. Besides the afferent vessels it is basically necessary to visualise the peripheral efferent pathways in order to prevent that vascular anastomosis to the split-skin flap obstructs the blood supply of the leg. (orig.)

  10. Occult breast carcinoma presenting as axillary metastases

    International Nuclear Information System (INIS)

    Purpose: Breast carcinoma presenting with axillary lymphadenopathy and no clinical or radiological evidence of a primary tumor is a rare presentation. We aimed to examine the management of the breast by observation, radiation therapy, or mastectomy. Methods and Materials: Departmental records from 1979 to 1996 of unknown primary presentations and cases of T0N1-2M0 breast carcinoma were reviewed to find cases of occult breast carcinoma presenting as axillary lymphadenopathy with no clinical or imaging evidence of a primary tumor. Results: There were 6047 presentations of breast carcinoma with 20 cases of occult breast carcinoma meeting the criteria. The breast was treated by observation in 6 cases, mastectomy in 2 cases, and radiotherapy to the intact breast in 12 cases. Eighty-three percent of patients (5 of 6 patients) who had observation of the breast had a local recurrence, compared to 25% who had radiotherapy to the intact breast (3 of 12 patients) and 0% who had a mastectomy (0 of 2 patients). The median recurrence-free survival was 7 months in patients who had observation of the breast, compared to 182 months in patients who had local treatment. Three of the 6 patients who underwent breast observation have died whereas 1 of the 14 who had local treatment have died, with a mean follow-up of 73 months. It was found that patients having observation of the breast had a poorer recurrence-free survival (p = 0.003) and overall survival (p = 0.05) compared to those having local treatment of the breast. Conclusions: Patients with such a presentation should have a complete physical examination, mammography, ultrasound, and MRI of the breasts. If there remains no evidence of a primary tumor, an axillary dissection should be carried out and the breast treated by radiotherapy or mastectomy. Observation of the breast is not a recommended option

  11. Intensity Scintillations in Planetary Ring Occultations: Simulations

    Science.gov (United States)

    Marouf, E.

    2003-12-01

    A combined analytical and numerical simulation approach is used to investigate the first, second, and fourth statistical averages of the signal observed during a ring occultation experiment. The rings are modeled as a randomly blocked diffraction screen. The field behind the screen (the rings) assumes binary values: zero if located in the shadow area cast by ring particles and the full incident field otherwise. The stochastic geometry of the union of shadow areas cast behind the rings defines a so-called Boolean model. Either the random wavefront formed behind the screen or it's statistical averages can be propagated to an observer (a detector) some distance away from the diffraction screen. The parabolic approximation of the wave equation is used to model near-forward diffraction effects over the free-space path from the ring plane to the observation plane. The first and second moments were previously shown to correspond to the well-known coherent and scattered signal components observed during radio occultation experiments. Of particular interest here is the fourth moment of the random field at the observer, which determines the intensity scintillation index. Numerical simulations are used to investigate its behavior as a function of relevant model parameters, in particular, the ring particle radius and the Fresnel scale of observation. A monodispersion of ring particles is assumed to keep the model as simple as possible so as to investigate conditions under which the particle size may be recoverable from the intensity scintillation measurements. The model is also idealized to one-dimensional diffraction screen in order to speed up the computations; however, simulations of the more realistic two-dimensional diffraction screen models are also carried out.

  12. Association of preS/S Mutations with Occult Hepatitis B Virus (HBV) Infection in South Korea: Transmission Potential of Distinct Occult HBV Variants

    OpenAIRE

    Hong Kim; Bum-Joon Kim

    2015-01-01

    Occult hepatitis B virus infection (HBV) is characterized by HBV DNA positivity but HBV surface antigen (HBsAg) negativity. Occult HBV infection is associated with a risk of HBV transmission through blood transfusion, hemodialysis, and liver transplantation. Furthermore, occult HBV infection contributes to the development of cirrhosis and hepatocellular carcinoma. We recently reported the characteristic molecular features of mutations in the preS/S regions among Korean individuals with occult...

  13. Asteroid occultations today and tomorrow: toward the GAIA era

    CERN Document Server

    Tanga, P

    2008-01-01

    Context: Observation of star occultations is a powerful tool to determine shapes and sizes of asteroids. This is key information necessary for studying the evolution of the asteroid belt and to calibrate indirect methods of size determination, such as the models used to analyze thermal infrared observations. Up to now, the observation of asteroid occultations is an activity essentially secured by amateur astronomers equipped with small, portable equipments. However, the accuracy of the available ephemeris prevents accurate predictions of the occultation events for objects smaller than ~100 km. Aims: We investigate current limits in predictability and observability of asteroid occultations, and we study their possible evolution in the future, when high accuracy asteroid orbits and star positions (such as those expected from the mission Gaia of the European Space Agency) will be available. Methods: We use a simple model for asteroid ephemeris uncertainties and numerical algorithms for estimating the limits impo...

  14. An Outrigger Component for a Deployable Occulter System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase II, Roccor proposes to build upon the results of Phase I to increase the technology readiness level (TRL) of the NASA JPL deployable external occulter. An...

  15. Sizes, Shapes, and Satellites of Asteroids from Occultations

    Science.gov (United States)

    Dunham, David W.; Herald, David; Preston, Steve; Timerson, Brad; Maley, Paul; Frappa, Eric; Hayamizu, Tsutomu; Talbot, John; Poro, Atila

    2016-01-01

    For 40 years, the sizes and shapes of many dozens of asteroids have been determined from observations of asteroidal occultations, and over a thousand high-precision positions of the asteroids relative to stars have been measured. Some of the first evidence for satellites of asteroids was obtained from the early efforts; now, the orbits and sizes of some satellites discovered by other means have been refined from occultation observations. Also, several close binary stars have been discovered, and the angular diameters of some stars have been measured from analysis of these observations. The International Occultation Timing Association (IOTA) coordinates this activity worldwide, from predicting and publicizing the events, to accurately timing the occultations from as many stations as possible, and publishing and archiving the observations.

  16. Photoreceptor atrophy in acute zonal occult outer retinopathy

    DEFF Research Database (Denmark)

    Zibrandtsen, N.; Munch, I.C.; Klemp, K.;

    2006-01-01

    Purpose: To assess retinal morphology in acute zonal occult outer retinopathy (AZOOR). Methods: Three patients with a normal ophthalmoscopic fundus appearance, a history of photopsia, and visual field loss compatible with AZOOR were examined using optical coherence tomography, automated perimetry...

  17. Occult foreign bodies in the aero digestive tracts in infancy

    OpenAIRE

    Saha, Somnath; Mishra, Saibal; Chakraborty, D. D.; Sengupta, Subhabrata; Mondal, A. R.

    2008-01-01

    Foreign body impaction in aero digestive tract in infancy is difficult to diagnose sometimes. In this review of five unusual cases of occult foreign body impaction in aero digestive tract has been presented and their management discussed

  18. Fecal Occult Blood Test and Fecal Immunochemical Test

    Science.gov (United States)

    ... Visit Global Sites Search Help? Fecal Occult Blood Test and Fecal Immunochemical Test Share this page: Was this page helpful? Also ... Test Common Questions Ask Us Related Pages The Test How is it used? When is it ordered? ...

  19. A Close Binary Star Resolved from Occultation by 87 Sylvia

    CERN Document Server

    Lin, Chi-Long; Chen, W P; King, Sun-Kun; Lin, Hung-Chin; Bianco, F B; Lehner, M J; Coehlo, N K; Wang, J -H; Mondal, S; Alcock, C; Axelrod, T; Byun, Y -I; Cook, K H; Davé, R; De Pater, I; Porrata, R; Kim, D -W; Lee, T; Lissauer, J J; Marshall, S L; Rice, J A; Schwamb, M E; Wang, S -Y; Wen, C -Y

    2009-01-01

    The star BD+29 1748 was resolved to be a close binary from its occultation by the asteroid 87 Sylvia on 2006 December 18 UT. Four telescopes were used to observe this event at two sites separated by some 80 km apart. Two flux drops were observed at one site, whereas only one flux drop was detected at the other. From the long-term variation of Sylvia, we inferred the probable shape of the shadow during the occultation, and this in turn constrains the binary parameters: the two components of BD+29 1748 have a projected separation of 0.097" to 0.110" on the sky with a position angle 104 deg to 107 deg. The asteroid was clearly resolved with a size scale ranging from 130 to 290 km, as projected onto the occultation direction. No occultation was detected for either of the two known moonlets of 87 Sylvia.

  20. Analysis from Stellar Occultation and Lightcurve Observation of 582 Olympia

    Science.gov (United States)

    Matsuoka, Y.; Okamoto, R.; Sugimoto, S.; Mayu Shibata; Watanabe, D.

    2012-05-01

    Our aim is to estimate 3D shape of an asteroid. We tried to find the shape of 582 Olympia. We conducted two observations: stellar occulation and lightcurve of an asteroid. We have observed lightcurves and occultations of several asteroid.

  1. UARS Halogen Occultation Experiment (HALOE) Level 2 V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The HALOE home page on the WWW is http://haloe.gats-inc.com/home/index.php The Halogen Occultation Experiment (HALOE) on NASA's Upper Atmosphere Research Satellite...

  2. Correlation of Doppler-detected tumor vascular signals with vascular morphology

    International Nuclear Information System (INIS)

    Abnormal vascular morphology exists in many malignant tumors, including arterio-venous anastomoses, thin-walled vessels, and tumor lakes. These emit abnormal Doppler signals that allow tissue characterization. Doppler signals and angiographic and histologic findings were compared in 19 liver, kidney, adrenal, and pancreatic tumors. Abnormal signals were obtained in 18 (95%). These consisted of high frequencies exceeding 4 kHz (using a 3-MHz insonating frequency) which correlated with arterio-venous shunts on angiography. In 11 patients there were low impedance signals with little systolic/diastolic variation (pulsatility index 1-3). These correlated with thin-walled, sinusoidal vessels with endothelial lining but no muscular wall, and also correlated with dense tumor staining on angiography

  3. Gastroesophageal Variceal Filling and Drainage Pathways: An Angiographic Description of Afferent and Efferent Venous Anatomic Patterns

    OpenAIRE

    Gaba, Ron C.; Couture, Patrick M; Janesh Lakhoo

    2015-01-01

    Varices commonly occur in liver cirrhosis patients and are classified as esophageal (EV), gastroesophageal (GEV), or isolated gastric (IGV) varices. These vessels may be supplied and drained by several different afferent and efferent pathways. A working knowledge of variceal anatomy is imperative for Interventional Radiologists performing transjugular intrahepatic portosystemic shunt and embolization/obliteration procedures. This pictorial essay characterizes the angiographic anatomy of varic...

  4. Coronary angiographic findings in patients with glucometabolic abnormality and coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    李勇

    2012-01-01

    Objective To analyze the characteristics of coronary angiographic(CAG) findings in patients with glucometabolic abnormality and coronary heart disease (CAD).Methods A total of 130 patients with CAD confirmed by CAG were included in this study. The blood pressure, blood glucose

  5. Should incidental asymptomatic angiographic stenoses and occlusions be treated in patients with peripheral arterial disease?

    LENUS (Irish Health Repository)

    Keeling, Aoife N

    2009-09-01

    The clinical importance of angiographically detected asymptomatic lower-limb stenoses and occlusions is unknown. This study aims to (i) assess the clinical outcome of asymptomatic lesions in the lower limb, (ii) identify predictors of clinical deterioration, and (iii) determine which asymptomatic lower-limb lesions should be treated at presentation.

  6. 3D Reconstruction of Coronary Arteries from Angiographic Images: A Survey

    Directory of Open Access Journals (Sweden)

    Mahima Goyal

    2013-06-01

    Full Text Available X-Ray angiographyis considered to be the “golden standard” ofall times in the medical imaging field due to its wide range ofapplications. In this paper, a survey is performed on the basictechniques and the methodologies that have already beenproposed by various researchers in the field of 3D reconstructionof coronary arteries using one or more angiograms as inmonoplane or biplane angiographic systems or a volume of dataas in rotational angiographic systems. Also, the variousprocedures that need to be performed are stated and describedshowing the contribution of each step in the reconstructionprocess. These procedures include distortion correction, motioncompensation, feature extraction, background removal,projection geometry optimization and topology identification,surface visualization etc.X-Ray angiographyis considered to be the “golden standard” ofall times in the medical imaging field due to its wide range ofapplications. In this paper, a survey is performed on the basictechniques and the methodologies that have already beenproposed by various researchers in the field of 3D reconstructionof coronary arteries using one or more angiograms as inmonoplane or biplane angiographic systems or a volume of dataas in rotational angiographic systems. Also, the variousprocedures that need to be performed are stated and describedshowing the contribution of each step in the reconstructionprocess. These procedures include distortion correction, motioncompensation, feature extraction, background removal,projection geometry optimization and topology identification,surface visualization etc.

  7. Frequencies of occultations of stars by planets, satellites, and asteroids.

    Science.gov (United States)

    O'Leary, B.

    1972-01-01

    Calculations show that several occultations of stars by the large satellites of the outer planets, Pluto, and the large asteroids could be observed each decade with existing equipment at earth-based telescopes. A systematic program of occultation predictions and observations is urged in order to improve our knowledge about the atmospheres, sizes, shapes, topography, and positions of these poorly understood bodies, in support of forthcoming spacecraft missions to the outer solar system.

  8. Diagnostic value of mammography for occult breast cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnostic value of mammography in occult breast cancer. Methods: 23 cases of non- palpable breast lesions were examined with stereotactic-guided or surgical biopsy. Results: Pathological diagnosis included ductal carcinoma in sim (7), infiltrating ductal carcinoma (5), lobular carcinoma in sim (2), carcinoma simplex (3), 4 intraductal papillary carcinoma (4), scirrhous carcinoma (1), metastatic adenocarcinoma (1) in the axilla. Conclusion: Mammography is a commonly used and effective method in diagnosis of occult breast cancer. (authors)

  9. New perspectives in occult hepatitis C virus infection

    OpenAIRE

    Carreño, Vicente; Bartolomé, Javier; Castillo, Inmaculada; Quiroga, Juan Antonio

    2012-01-01

    Occult hepatitis C virus (HCV) infection, defined as the presence of HCV RNA in liver and in peripheral blood mononuclear cells (PBMCs) in the absence of detectable viral RNA in serum by standard assays, can be found in anti-HCV positive patients with normal serum levels of liver enzymes and in anti-HCV negative patients with persistently elevated liver enzymes of unknown etiology. Occult HCV infection is distributed worldwide and all HCV genotypes seem to be involved in this infection. Occul...

  10. First Results From The Taiwanese-American Occultation Survey (TAOS)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z; Bianco, F B; Lehner, M J; Coehlo, N K; Wang, J; Mondal, S; Alcock, C; Axelrod, T; Byun, Y; Chen, W P; Cook, K H; Dave, R; de Pater, I; Porrata, R; Kim, D; King, S; Lee, T; Lin, H; Lissauer, J J; Marshall, S L; Protopapas, P; Rice, J A; Schwamb, M E; Wang, S; Wen, C

    2008-08-22

    Results from the first two years of data from the Taiwanese-American Occultation Survey (TAOS) are presented. Stars have been monitored photometrically at 4 Hz or 5 Hz to search for occultations by small ({approx}3 km) Kuiper Belt Objects (KBOs). No statistically significant events were found, allowing us to present an upper bound to the size distribution of KBOs with diameters 0.5 km < D < 28 km.

  11. First Results From The Taiwanese-American Occultation Survey (TAOS)

    CERN Document Server

    Zhang, Z -W; Lehner, M J; Coehlo, N K; Wang, J -H; Mondal, S; Alcock, C; Axelrod, T; Byun, Y -I; Chen, W -P; Cook, K H; Davé, R; De Pater, I; Porrata, R; Kim, D -W; King, S -K; Lee, T; Lin, H -C; Lissauer, J J; Marshall, S L; Protopapas, P; Rice, J A; Schwamb, M E; Wang, S -Y; Wen, C -Y

    2008-01-01

    Results from the first two years of data from the Taiwanese-American Occultation Survey (TAOS) are presented. Stars have been monitored photometrically at 4 Hz or 5 Hz to search for occultations by small (~3 km) Kuiper Belt Objects (KBOs). No statistically significant events were found, allowing us to present an upper bound to the size distribution of KBOs with diameters 0.5 km < D < 28 km.

  12. Earth Occultation Monitoring with the Fermi Gamma Ray Burst Monitor

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2014-01-01

    Using the Gamma Ray Burst Monitor (GBM) on-board Fermi, we are monitoring the hard X-ray/soft gamma ray sky using the Earth occultation technique (EOT). Each time a source in our catalog is occulted by (or exits occultation by) the Earth, we measure its flux using the change in count rates due to the occultation. Currently we are using CTIME data with 8 energy channels spanning 8 keV to 1 MeV for the GBM NaI detectors for daily monitoring. Light curves, updated daily, are available on our website http://heastro.phys.lsu.edu/gbm. Our software is also capable of performing the Earth occultation monitoring using up to 128 energy bands, or any combination of those bands, using our 128-channel, 4-s CSPEC data. The GBM BGO detectors, sensitive from about 200 keV to 40 keV, can also be used with this technique. In our standard application of the EOT, we use a catalog of sources to drive the measurements. To ensure that our catalog is complete, our team has developed an Earth occultation imaging method. In this talk, I will describe both techniques and the current data products available. I will highlight recent and important results from the GBM EOT, including the current status of our observations of hard X-ray variations in the Crab Nebula.

  13. Diagnostic strategy for occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Sara Ocana; Maria Luisa Casas; Ingrid Buhigas; Jose Luis Lledo

    2011-01-01

    In 2008, the European Association for the study of the liver (EASL) defined occult hepatitis B virus infection (OBI) as the "presence of hepatitis B virus (HBV) DNA in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen (HBsAg) negative by currently available assays". Several aspects of occult HBV infection are still poorly understood, including the definition itself and a standardized approach for laboratory-based detection, which is the purpose of this review. The clinical significance of OBI has not yet been established; however, in terms of public health, the clinical importance arises from the risk of HBV transmission. Consequently, it is important to detect high-risk groups for occult HBV infection to prevent transmission. The main issue is, perhaps, to identify the target population for screening OBI. Viremia is very low or undetectable in occult HBV infection, even when the most sensitive methods are used, and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients. However, this diagnostic approach is obviously unsuitable: blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection < 10 IU/mL for HBV DNA and < 0.1 ng/mL for HBsAg.

  14. Venous thromboembolism and occult cancer: impact on clinical practice.

    Science.gov (United States)

    Gheshmy, Afshan; Carrier, Marc

    2016-04-01

    Unprovoked venous thromboembolism (VTE) can be the first manifestation of cancer. Given this relationship between unprovoked VTE and cancer, it is appealing for clinicians to screen their patients with a first episode of acute unprovoked VTE for a potential occult malignancy. Five different studies have compared a limited (thorough history and physical exam, basic bloodwork) to a more extensive occult cancer screening strategy (e.g. computed tomography, fludeoxyglucose positron emission tomography, etc.). Most of these studies have failed to show that an extensive occult cancer screening strategy diagnoses more occult cancer (including early cancers), misses fewer cancers during follow-up or improves overall and/or cancer-related mortality suggesting that extensive occult cancer screening should not be performed routinely. Therefore, patients with a first unprovoked VTE should undergo a limited cancer screening only and clinicians should ensure that their patients are up to date regarding age- and gender- specific cancer screening (colon, breast, cervix and prostate) as per their national recommendations. Current evidence does not support a net clinical benefit to perform an extensive occult cancer screening on all patients, and a decision to do additional testing should be made on a case by case basis. PMID:27067984

  15. Possible occultation by Pluto from US East Coast

    Science.gov (United States)

    Waagen, Elizabeth O.

    2012-06-01

    We have been asked to help disseminate the news of a possible occultation by Pluto visible to observers on the US East coast. Although the AAVSO does not ordinarily issue announcements of upcoming occultations, in this case the object is Pluto and the NASA New Horizons mission (http://www.nasa.gov/mission_pages/newhorizons/main/index.html) will be visiting Pluto in 2015. The information below has been supplied by Dr. Leslie Young (Southwest Research Institute), who is coordinating this observing campaign on Pluto. Dr. Young is also Deputy Project Scientist for the New Horizons mission. ALERT: Possible Pluto occultation Wednesday night (2012/06/14 03:28 UT) from US East coast. CONTACT: Leslie Young (layoung@boulder.swri.edu; work: 303-546-6057; skype: drpluto). Also see our planning pages in progress at http://wiki.boulder.swri.edu/mediawiki/index.php/2012-06-14_Pluto_occultation. Pluto's thin, nitrogen atmosphere is in vapor-pressure equilibrium with the surface ice, and changes seasonally. We've seen it double since 1988, and now we measure its pressure once or twice a year. The technique we use is stellar occultation, when a star passes behind Pluto's atmosphere. The atmosphere defocuses the starlight. By the timing of the fading of the star, we measure the pressure and temperature in Pluto's atmosphere at ~10 km resolution. MORE INFORMATION: See http://wiki.boulder.swri.edu/mediawiki/index.php/2012-06-14_Pluto_occultation.

  16. Society for Vascular Medicine

    Science.gov (United States)

    ... and find out! Patient Information Pages from Vascular Medicine August 2016 The Vascular Laboratory More info for ... Learn more. Trending Now: Hot Topics in Vascular Medicine Video Series Fibromuscular Dysplasia (FMD) with Drs. Jeffrey ...

  17. Diverse Applications of Occultation Data in Ozone Assimilation

    Science.gov (United States)

    Markowitz, A.; Uttley, P.

    2005-01-01

    Ozone profiles from solar occultation instruments provide invaluable information that can be used to evaluate the quality of assimilated ozone fields, from case studies to long-term phenomena. Occultation data can also be applied to include physical constraints while developing components of an assimilation system. Conversely, assimilation of occultation data can help in their validation, and it provides a framework for evaluation of the impact of occultation data on constraining global ozone fields within models. We illustrate these diverse applications by a series of examples using the ozone assimilation system at NASA/Goddard. In a case study, low ozone in the lower stratosphere due to transport of air from the Tropics to northern high latitudes that was captured by assimilation of Aura Microwave Limb Sounder (MLS) and Solar Backscatter Ultraviolet (SBUV) data, was found to agree with SAGE III data. For long-term monitoring, the quality of a multi-year SBUV-only assimilation was evaluated using monthly-mean time series of POAM, HALOE, and SAGE I1 data. We found realism in the representation of the annual cycle in ozone and in some aspects of interannual variability. Assimilation of POAM data was shown to improve the representation of lower stratospheric ozone, especially over Antarctica. More recently, we assimilated ILAS II ozone data in order to help in their validation. Solar occultation data are used to estimate parameters in a new model for forecast error variances that is being developed. These examples demonstrate the importance of occultation data for ozone assimilation, and potential of assimilation to increase the impact and the value of occultation data.

  18. MRI of radiographically occult ischial apophyseal avulsions

    International Nuclear Information System (INIS)

    Acute avulsions of unossified ischial apophyses in children may go undetected on radiography. Therapy includes rest and rehabilitation; however, substantial displacement may require surgery. Our purpose is to illustrate the utility of MRI in the detection of these radiographically occult injuries in skeletally immature children. This retrospective study of more than 5 years included children with ischial avulsions who were evaluated with both radiography and MRI within 3 weeks of acute injury. Initially, radiographs were reviewed to identify those children with unossified ischial apophyses. Subsequently, their MRI examinations were assessed for physeal disruption, bone/soft tissue edema, periosteal/perichondrial elevation and disruption. Initial and follow-up radiographs (if available) were reviewed. Patient age, symptoms and offending activity were determined from clinical records. Five children met inclusion criteria. All initial radiographs were normal. MRI showed: edema (n = 5), periosteal elevation (n = 4), periosteal/perichondrial disruption (n = 4), >5.5 mm displacement (n = 0). Follow-up radiographs in two children (2 and 2.5 months from MRI) showed osseous ischial irregularity. The apophyses remained unossified. Acute unossified ischial apophyseal avulsions in children may be radiographically undetected. In the setting of correlative clinical symptoms, MRI can be used to identify these injuries and to help direct appropriate therapy. (orig.)

  19. Not all occult papillary carcinomas are minimal

    International Nuclear Information System (INIS)

    Occult papillary carcinomas are characterized as small papillary tumors of less than 1.5 cm in maximum diameter, with or without bulky metastatic deposits in cervical nodes. The primary lesion is usually not palpable, and although the clinical behavior usually follows a benign course, tumors with unfavorable histologic features (invasiveness, multifocality) or extrathyroidal disease or a combination of both may not do so. In this report six cases are presented to illustrate this entity. No patient had a history of irradiation to the head or neck. All had primary lesions smaller than 1.5 cm. None had a palpable nodule or abnormal thyroid scan results, and the diagnosis of thyroid cancer was based on cervical lymph node or lung biopsy specimens, which revealed papillary thyroid cancer. All of the patients underwent total or near-total thyroidectomies and were found to have small, invasive papillary lesions with additional metastases to cervical nodes noted at the time of thyroidectomy. Adjunctive treatment consisted of a 5 mCi iodine-131 scan, ablative iodine-131 therapy, and suppression with L-thyroxine. Although distant metastasis to lung or other organs is uncommon and the mortality rate is low (as in larger papillary cancers), these invasive lesions--despite their small size--have a high propensity for recurrence and should be considered to behave more like encapsulated papillary tumors with extrathyroidal extension than like their small, unencapsulated intrathyroidal counterparts

  20. MRI of radiographically occult ischial apophyseal avulsions

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, Arthur B. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, MLC 5031, Cincinnati, OH (United States); Children' s Hospital of Wisconsin, Milwaukee, WI (United States); Laor, Tal; Zbojniewicz, Andrew M.; Anton, Christopher G. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, MLC 5031, Cincinnati, OH (United States)

    2012-11-15

    Acute avulsions of unossified ischial apophyses in children may go undetected on radiography. Therapy includes rest and rehabilitation; however, substantial displacement may require surgery. Our purpose is to illustrate the utility of MRI in the detection of these radiographically occult injuries in skeletally immature children. This retrospective study of more than 5 years included children with ischial avulsions who were evaluated with both radiography and MRI within 3 weeks of acute injury. Initially, radiographs were reviewed to identify those children with unossified ischial apophyses. Subsequently, their MRI examinations were assessed for physeal disruption, bone/soft tissue edema, periosteal/perichondrial elevation and disruption. Initial and follow-up radiographs (if available) were reviewed. Patient age, symptoms and offending activity were determined from clinical records. Five children met inclusion criteria. All initial radiographs were normal. MRI showed: edema (n = 5), periosteal elevation (n = 4), periosteal/perichondrial disruption (n = 4), >5.5 mm displacement (n = 0). Follow-up radiographs in two children (2 and 2.5 months from MRI) showed osseous ischial irregularity. The apophyses remained unossified. Acute unossified ischial apophyseal avulsions in children may be radiographically undetected. In the setting of correlative clinical symptoms, MRI can be used to identify these injuries and to help direct appropriate therapy. (orig.)

  1. Occult celiac disease prevents penetrance of hemochromatosis

    Institute of Scientific and Technical Information of China (English)

    Andreas Geier; Siegfried Matern; Carsten Gartung; Igor Theurl; Guenter Weiss; Frank Lammert; Christoph G. Dietrich; Ralf Weiskirchen; Heinz Zoller; Benita Hermanns

    2005-01-01

    AIM: To report a patient with C282Y homozygocity, depleted body iron and intestinal atrophy caused by celiac disease (CD) who experienced resolution of the enteropathy with subsequent normalization of iron metabolism upon glutenfree diet.METHODS: To obtain information on the tissue distribution and quantitative expression of proteins involved in duodenal iron trafficking, we determined the expression of divalent-metal transporter 1 (DMT1), ferroportin 1 (FP1) and transferrin receptor (TfR1) by means of immunohistochemistry and real-time PCR in duodenal biopsies of this patient.RESULTS: Whereas in hereditary hemochromatosis patients without CD, DMT1 expression was up-regulated leading to excessive uptake of iron, we identified a significant reduction in protein and mRNA expression of DMT1 as acompensatory mechanism in this patient with HH and CD.CONCLUSION: Occult CD may compensate tot increased DMT1 expression in a specific subset of individuals withhomozygous C282Y mutations in the hemochromatosis(HFE) gene, thus contributing to the low penetrance of HH.

  2. The Extinction Law in an Occulting Galaxy

    CERN Document Server

    Berlind, Andreas A; Pogge, R W; Sellgren, K; Berlind, Andreas A.

    1997-01-01

    We measure the extinction law in a galaxy's spiral arm and interarm regions using a visual and infrared (BVRJHK) imaging study of the interacting galaxies NGC 2207 and IC 2163. This is an overlapping spiral galaxy pair in which NGC 2207 partially occults IC 2163. This geometry enables us to directly measure the extinction of light from the background galaxy as it passes through the disk of the foreground galaxy. We measure the extinction as a function of wavelength, and find that there is less extinction in the optical bands than expected from a normal Galactic extinction law. This deviation is significantly larger in the interarm region than in the spiral arm. The extinction curve in the spiral arm resembles a Milky Way $R_V=5.0$ dust model and the interarm extinction curve is flatter (``greyer'') still. We examine the effect of scattering of background galaxy light into the line of sight and find that it is negligible. We also examine the effect of an unresolved patchy dust distribution using a simple two-c...

  3. Celestial shadows eclipses, transits, and occultations

    CERN Document Server

    Westfall, John

    2015-01-01

    Much of what is known about the universe comes from the study of celestial shadows—eclipses, transits, and occultations.  The most dramatic are total eclipses of the Sun, which constitute one of the most dramatic and awe-inspiring events of nature.  Though once a source of consternation or dread, solar eclipses now lead thousands of amateur astronomers and eclipse-chasers to travel to remote points on the globe to savor their beauty and the adrenaline-rush of experiencing totality, and were long the only source of information about the hauntingly beautiful chromosphere and corona of the Sun.   Long before Columbus, the curved shadow of the Earth on the Moon during a lunar eclipse revealed that we inhabit a round world. The rare and wonderful transits of Venus, which occur as it passes between the Earth and the Sun, inspired eighteenth century expeditions to measure the distance from the Earth to the Sun, while the recent transits of 2004 and 2012 were the most widely observed ever--and still produced re...

  4. Vascular Abnormalities in the Head and Neck Area in Velocardiofacial Syndrome.

    Directory of Open Access Journals (Sweden)

    Jui-Pin Lai

    2004-08-01

    Full Text Available Background: Velocardiofacial syndrome (VCFS is a disorder commonly associated with acharacteristic facial appearance, congenital heart disease, and velopharyngealinsufficiency. An association with vascular anomalies in the cervical area andskull base has been reported. In this study, we evaluated 7 consecutivepatients who received vascular imaging for preoperative planning ofvelopharyngeal surgery.Methods: From January 1996 to September 1997, 7 patients with VCFS were found in1 of the senior author's service. All had documented velopharyngeal insufficiencyand visible pulsations over the posterior pharyngeal wall by nasoendoscopy.Two patients had magnetic resonance angiography (MRA, 2patients had computed tomographic angiography (CTA, and 3 patients hadboth.Results: The angiographic study revealed abnormalities of the carotid and vertebralarteries in 5 patients (71%. Kinking and tortuosity of the internal carotidartery and its medial displacement were common. The observed pulsationsdid not correlate well with the angiographic findings. For surgical correctionof the velopharyngeal sufficiency, a regular pharyngeal flap was used in 4patients, a modified pharyngeal flap was used in 2 patients, and the surgerywas abandoned in the remaining 1 patient.Conclusions: Expression of cervical vascular anomalies in VCFS was varied and did notcorrelate well with the observed pulsations from the nasopharyngoscopicexamination. Preoperative vascular imaging study is essential for the purposeof planning and safety of surgical interventions in this area.

  5. The Taiwanese-American Occultation Survey: The Multi-Telescope Robotic Observatory

    CERN Document Server

    Lehner, M J; Wang, J -H; Marshall, S L; Schwamb, M E; Zhang, Z -W; Bianco, F B; Giammarco, J; Porrata, R; Alcock, C; Axelrod, T; Byun, Y -I; Chen, W P; Cook, K H; Davé, R; King, S -K; Lee, T; Lin, H -C; Wang, S -Y

    2008-01-01

    The Taiwanese-American Occultation Survey (TAOS) operates four telescopes to search for occultations of stars by Kuiper Belt Objects. This paper provides a detailed description of the TAOS multi-telescope system.

  6. Popliteal artery branching patterns-an angiographic study

    Energy Technology Data Exchange (ETDEWEB)

    Day, C.P. [Department of Radiology, Royal Shrewsbury Hospital, Shrewsbury (United Kingdom)]. E-mail: chris.laura2001@ntlworld.com; Orme, R. [Department of Radiology, Royal Shrewsbury Hospital, Shrewsbury (United Kingdom)

    2006-08-15

    AIM: To analyse the variations in branching patterns of the popliteal artery and infrapopliteal vessels using angiography. MATERIALS And METHODS: Femoral angiograms of 1037 lower limbs in 568 patients were examined to assess the popliteal artery branching pattern. Variations of the infrapopliteal vessels supplying the foot were assessed in 662 limbs from the same cohort of patients. RESULTS: Nine hundred and forty-one (90.7%) limbs had the usual branching pattern with anterior tibial artery (AT) arising first followed by the tibial-peroneal trunk (TPT), which then gives rise to the posterior tibial (PT) and peroneal (PR) arteries. Variations in popliteal branching pattern were seen in 96 (9.3%) limbs. The commonest variation is high origin of the AT in 47 (4.5%) limbs or trifurcation of the popliteal artery in 33 (3.2%) limbs with AT, PT and PR arising together with no true TPT. The course of AT with high origin either anterior or posterior to popliteus was almost equal [25 (2.4%) or 22 (2.1%) limbs, respectively]. Eleven limbs (1.1%) had high origin of PT and two (0.2%) had a high origin of the PR. Six hundred and fifty-five (99%) limbs had normal infrapopliteal vessels. Seven (1%) had hypoplasia-aplasia of the infrapopliteal vessels. Five (0.8%) limbs had a hypoplastic PT with the remaining 2 (0.2%) having either a hypoplastic-aplastic AT or hypoplasia-aplasia of both AT and PT. CONCLUSION: Variations in the branching of the popliteal artery occur in about 10% of patients. Knowledge of these variations is important because of the potential consequences for the management of peripheral vascular disease.

  7. Popliteal artery branching patterns-an angiographic study

    International Nuclear Information System (INIS)

    AIM: To analyse the variations in branching patterns of the popliteal artery and infrapopliteal vessels using angiography. MATERIALS And METHODS: Femoral angiograms of 1037 lower limbs in 568 patients were examined to assess the popliteal artery branching pattern. Variations of the infrapopliteal vessels supplying the foot were assessed in 662 limbs from the same cohort of patients. RESULTS: Nine hundred and forty-one (90.7%) limbs had the usual branching pattern with anterior tibial artery (AT) arising first followed by the tibial-peroneal trunk (TPT), which then gives rise to the posterior tibial (PT) and peroneal (PR) arteries. Variations in popliteal branching pattern were seen in 96 (9.3%) limbs. The commonest variation is high origin of the AT in 47 (4.5%) limbs or trifurcation of the popliteal artery in 33 (3.2%) limbs with AT, PT and PR arising together with no true TPT. The course of AT with high origin either anterior or posterior to popliteus was almost equal [25 (2.4%) or 22 (2.1%) limbs, respectively]. Eleven limbs (1.1%) had high origin of PT and two (0.2%) had a high origin of the PR. Six hundred and fifty-five (99%) limbs had normal infrapopliteal vessels. Seven (1%) had hypoplasia-aplasia of the infrapopliteal vessels. Five (0.8%) limbs had a hypoplastic PT with the remaining 2 (0.2%) having either a hypoplastic-aplastic AT or hypoplasia-aplasia of both AT and PT. CONCLUSION: Variations in the branching of the popliteal artery occur in about 10% of patients. Knowledge of these variations is important because of the potential consequences for the management of peripheral vascular disease

  8. The FREEDOM Trial: Clinical and Angiographic Profile at Study Entry

    Science.gov (United States)

    Bansilal, Sameer; Farkouh, Michael E.; Hueb, Whady; Ogdie, May; Dangas, George; Lansky, Alexandra J; Cohen, David J; Magnuson, Elizabeth A; Ramanathan, Krishnan; Tanguay, Jean-Francois; Muratov, Victoria; Sleeper, Lynn A; Domanski, Michael; Bertrand, Michel E; Fuster, Valentin

    2015-01-01

    Background The optimal revascularization strategy for diabetic patients with multivessel coronary artery disease (MVD) remains uncertain for lack of an adequately powered, randomized trial. The FREEDOM trial was designed to compare contemporary coronary artery bypass grafting (CABG) to percutaneous coronary intervention (PCI) with drug-eluting stents in diabetic patients with MVD against a background of optimal medical therapy. Methods A total of 1900 diabetic subjects with MVD were randomized to PCI or CABG worldwide from April 2005–March 2010. FREEDOM is a superiority trial with a mean follow-up of 4.37 years (minimum 2 years) and 80% power to detect a 27.0% relative reduction. We present the baseline characteristics of patients screened and randomized, and provide a comparison with other MVD trials involving diabetic patients. Results The randomized cohort was 63.1±9.1 years old and 29% female with median diabetes duration 10.2±8.9 years. Most (83%) had three-vessel disease and on average took 5.5±1.7 vascular medications, with 32% on insulin therapy. Nearly all had hypertension and/or dyslipidemia and 26% had a prior myocardial infarction. Mean HbA1C was 7.8±1.7 mg/dl, 29% had low-density lipoprotein<70 mg/dl and mean systolic blood pressure was 134±20 mmHg. The mean SYNTAX score was 26.2 with a symmetric distribution. FREEDOM trial subjects have baseline characteristics similar to those of contemporary multivessel and diabetes trial cohorts. Conclusions The FREEDOM trial has successfully recruited a high-risk diabetic MVD cohort. Follow-up efforts include aggressive monitoring to optimize background risk factor control. FREEDOM will contribute significantly to the PCI vs. CABG debate in diabetic subjects with MVD. PMID:23067919

  9. The pretzel sign: angiographic pattern of tortuous intra-aneurysmal blood flow in a giant serpentine aneurysm.

    LENUS (Irish Health Repository)

    Fanning, N F

    2012-02-03

    Giant serpentine aneurysms (GSAs) form a specific subgroup of giant cerebral aneurysms that have pathognomonic angiographic features. We report the angiographic findings of a GSA demonstrating a striking convoluted dynamic flow pattern, which we have called the \\'pretzel sign\\'. The aneurysm was successfully treated by permanent occlusion of the parent vessel using a detachable balloon. GSAs should be identified prior to treatment in view of their particular management requirements.

  10. Serum Cystatin C Reflects Angiographic Coronary Collateralization in Stable Coronary Artery Disease Patients with Chronic Total Occlusion

    OpenAIRE

    Shen, Ying; Ding, Feng Hua; Zhang, Rui Yan; Zhang, Qi; Lu, Lin; Shen, Wei Feng

    2015-01-01

    Objective We investigated whether and to what extent cystatin C was associated with angiographic coronary collateralization in patients with stable coronary artery disease and chronic total occlusion. Methods Serum levels of cystatin C and high-sensitive C-reactive protein (hsCRP) and glomerular filtration rate (GFR) were determined in 866 patients with stable angina and angiographic total occlusion of at least one major coronary artery. The degree of collaterals supplying the distal aspect o...

  11. MR angiographic and parenchymal evaluation of cerebral infaraction in sickle cell anemia

    International Nuclear Information System (INIS)

    Cerebral infarction is an important complication of sickle cell anemia, believed to be related to large-vessel stenoses/occlusion and/or capillary/venous sickling resulting in thrombosis. Identification of these complications (especially large-vessel arterial disease) is important in selecting patients for transfusion therapy. The purpose of this study was to determine the suitability of combined three-dimensional Fourier transform time-of-flight MR angiographic and parenchymal T2-weighted spin-echo examinations for evaluation of central nervous system (CNS) complications of sickle cell anemia. Seven patients (age range, 5-14 years) were evaluated. Five had documented strokes while two had symptoms resembling those of transient ischemic attack. The preliminary data indicate that combined MR angiographic and parenchymal studies are capable of identifying those patients with sickle cell anemia complicated by large-vessel CNS occlusive disease and cerebral infarction and can be used as a noninvasive guide to therapy

  12. Inadvertent Intra-arterial Drug Injections: The Role of Angiographic and Clinical Findings

    Energy Technology Data Exchange (ETDEWEB)

    Rautio, R. [Turku Univ. Hospital (Finland). Dept. of Radiology; Keski-Nisula, L. [Tampere Univ. Hospital (Finland). Dept. of Radiology

    2006-07-15

    Purpose: To evaluate the angiographic findings of patients who have inadvertently injected oral formulations of drugs into an upper extremity artery. Material and Methods: The radiology files for the previous 4 years were analyzed retrospectively. Seven patients were referred from the Emergency Dept. for angiography and possible thrombolysis during that time period. Results: The worst clinical results were found among the patients whose angiographic examinations showed absent flow. Two patients who were treated with local thrombolysis had no better results compared to the other five patients. Conclusion: Findings of delayed flow and absent flow in angiography should lead to intensified conservative treatment, especially among patients who have clinical findings of delayed capillary refilling or/and impaired muscular strength.

  13. Mutations Associated With Occult Hepatitis B in HIV-Positive South Africans

    OpenAIRE

    Powell, Eleanor A.; Gededzha, Maemu P; Rentz, Michael; Rakgole, Nare J.; Selabe, Selokela G.; Seleise, Tebogo A.; Mphahlele, M Jeffrey; Blackard, Jason T.

    2014-01-01

    Occult hepatitis B is characterized by the absence of hepatitis B surface antigen (HBsAg) but the presence of HBV DNA. Because diagnosis of hepatitis B virus (HBV) typically includes HBsAg detection, occult HBV remains largely undiagnosed. Occult HBV is associated with increased risk of hepatocellular carcinoma, reactivation to chronic HBV during immune suppression, and transmission during blood transfusion and liver transplant. The mechanisms leading to occult HBV infection are unclear, alth...

  14. The occultation of Surrealism: a study of the relationship between Bretonian Surrealism and western esotericism

    OpenAIRE

    Hanegraaff, W.J.; Bauduin, T.M.

    2012-01-01

    It has been said that Surrealism was nothing if not deeply involved with occultism and Western esotericism. Others claim that there was no such involvement or even that Surrealism was directly opposed to the occult and esoteric. ‘The occultation of Surrealism’ offers a fresh view of this complex and important debate that has remained unresolved until now, and seeks to account for such differing opinions about the supposedly occult character of Surrealism, specifically under the leadership of ...

  15. Serum high sensitivity C-reactive protein levels and the severity of coronary atherosclerosis assessed by angiographic gensini score

    International Nuclear Information System (INIS)

    Objective: To assess the relationship between plasma high sensitivity C-reactive protein levels with severity of coronary atherosclerosis. Materials and Methods: The study included 80 patients subjected to coronary angiography. The extent of Coronary Artery Disease (CAD) was assessed using Gensini score. Patients were divided into three risk groups according to hs-CRP levels (3mg/L- as high risk). Mean Angiographic Gensini scores were compared among the risk groups. Correlation between serum hs-CRP levels and angiographic Gensini scores was also assessed. Results: The 26 (32.5%) patients belonging to hs-CRP low-risk group had a mean angiographic Gensini score of 11.8 +- 5.8, 18 (22.5%) belonging to moderate-risk group had a mean score of 28.9 +- 7.9 and 36 (45%) belonging to high- risk group had a mean score of 78.7 +- 41.0. By applying ANOVA the mean angiographic Gensini scores showed increasing trend from lower to higher hs-CRP risk groups (p < 0.001). Serum hs-CRP levels showed significant correlation with respective angiographic Gensini scores by Pearson's correlation (p < 0.001). Conclusion: Serum hs-CRP levels show significant correlation with the severity of Coronary Artery Disease as assessed by angiographic Gensini score. (author)

  16. Probing Planetary Formation and Evolution Through Occultations

    Science.gov (United States)

    Rodriguez, Joseph E.; KELT Team

    2016-01-01

    The circumstellar environments of young stellar objects (YSOs) involve complex dynamical interactions between dust and gas that directly influence the formation of planets. However, our understanding of the evolution from the material in the circumstellar disk to the thousands of planetary systems discovered to date, is limited. One means to better constrain the size, mass, and composition of this planet-forming material is to observe a YSO being eclipsed by its circumstellar disk. Through this dissertation project, we are discovering and characterizing both disk eclipsing systems and exoplanets using the Kilodegree Extremely Little Telescope (KELT) project. KELT is a photometric survey for transiting planets orbiting bright stars (8 < V < 11); such bright planet host targets are well-suited for atmospheric characterization of the planets. KELT has discovered 15 planets transiting stars brighter than V ~11 to date. I will present some of the recently discovered planets from the survey and discuss their potential to advance our understanding of planetary atmospheres. In addition, KELT provides photometric monitoring of ~3 million stars, presenting the opportunity to perform multi-year studies of stellar variability generally and rare disk occultations specifically. Using time-series photometry from KELT we are conducting the Disk Eclipse Search with KELT (DESK) survey to look for disk eclipsing events, specifically in young stellar associations. To date, the survey has discovered and analyzed four previously unknown large dimming events around the stars RW Aurigae, V409 Tau, AA Tau, and TYC 2505-672-1, the latter now representing the longest-period eclipsing object known (period ~ 69 years). I will describe our results for planet atmosphere characterization and for protoplanetary disk structure and composition, and discuss how to search for these kinds of systems in future surveys such as LSST.

  17. Treatment of blue digit syndrome with percutaneous transluminal angioplasty-angiographic features

    International Nuclear Information System (INIS)

    Since 1978, the authors have treated nine patients with blue toe syndrome and one patient with blue finger syndrome using percutaneous transluminal angioplasty rather than surgery. None of the patients had distal embolization as a consequence of the balloon dilation. Nine patients have had no evidence of recurrent embolization on follow-up. One patient had a questionable single episode of recurrent embolization. The angiographic, hemodynamic, and clinical features of these ten patients which have been associated with a successful result are outlined

  18. Myocardial bridging: retrospective analysis and scintigraphic testing of patients with no angiographically significant atherosclerotic coronary disease.

    OpenAIRE

    Luz, A.C.; J. Silveira; P. Palma; Cyrne-Carvalho, H.; Albuquerque, A.; I. Amorim; Gomes, L.

    2006-01-01

    Rev Port Cardiol. 2006 Apr;25(4):397-406. Myocardial bridging: retrospective analysis and scintigraphic testing of patients with no angiographically significant atherosclerotic coronary disease. [Article in English, Portuguese] Luz A, Silveira J, Palma P, Carvalho HC, Albuquerque A, Amorim I, Gomes L. SourceServiço de Cardiologia, Hospital Geral de Santo António, Porto, Portugal. Abstract INTRODUCTION AND OBJECTIVE: The clinical relevance of myocardial bri...

  19. MYOCARDIAL BRIDGING - CLINICAL AND ANGIOGRAPHIC PROFILE IN LAST 5 YEARS; A STUDY OF 129 CASES

    OpenAIRE

    Abhilash S P; Krishna Kumar B; Praveen Velappan; PrabhaniniGupta; Sunita Viswanathan; A. George Koshy

    2010-01-01

    Aims of study : To assess the clinical and angiographical profile of myocardial bridging from consecutive coronary angiograms done over last 5 years at Medical college, Thiruvananthapuram. To assess the risk of cardiovascular events and the risk of accelerated atherosclerosis in isolated myocardial bridging. Methods : Consecutive coronary angiograms done at Medical college Thiruvananthapuram from 04/02/2005 to 31/03/2010 were reviewed for myocardial bridging. A total of 10492 coronary angiogr...

  20. System for the quantitative evaluation of angiographic and scintigraphic pictures of the left ventricle

    International Nuclear Information System (INIS)

    There are many parallels between the evaluation of cardiac scintiscans and that of angiographic ventriculograms; therefore, a scintigraphic system of evaluation has been modified so that also ventriculographic evaluations have become possible. It was of advantage for this development that scintigraphic data input in cardiological practice is usually carried out off-line using a mobile camera, and data system, e.g. in the cardiac supervision department or in heart catheter laboratories. (orig.)

  1. Dural arteriovenous fistula at marginal sinus: angiographic findings and treatment with transvenous coil embolization

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the angiographic findings of dural arteriovenous fistulas(dAVFs) at the site of a marginal sinus and to assess the efficacy of transvenous embolizations. Six patients in whom an angiographically confirmed dural arteriovenous fistula was present at the site of a marginal sinus were involved in this study. Arterial feeders and the venous drainage of dAVFs were evaluated, and we describe the location of other combined dAVFs. Transvenous, with or without arterial, embolization was performed in all patients, and the angiographic findings and clinical outcomes were evaluated. Ascending pharyngeal and occipital arteries were the main arterial feeders, and dAVFs were also supplied from the meningohypophyseal trunk, posterior auricular artery, middle meningeal arteries, and the accessory meningeal, internal maxillary, and meningeal branch of the vertebral artery. In five of six cases, the supply originated not only from the ipsilateral arterial system, but also from the contralateral system. Posterior venous drainage occurred via the internal jugular vein and the paravertebral venous plexus, and superiorly, via the and cavernous sinus. Au six patients underwent transvenous coil embolization. Except in one case, in which drainage involved the paravertebral venous plexus, the venous route of embolization was the internal jugular vein. In four of six patients, angiography revealed complete occlusion of the fistula, and the clinical symptoms showed complete resolution. In the other two cases there was minimal residual flow, but the clinical symptoms showed improvement. In both, a further fistula was seen at a site other than the marginal sinus. In all patients, the angiographic findings were evaluated and subsequent endovascular treatment was successful. Transvenous embolization involving dAVFs at the site of a marginal sinus were effective; clinical outcomes depended on successful endovascular treatment and the extent of dAVFs

  2. Angiographic findings after supplementation with Heracleum persicum extract: Results of a randomized controlled trial

    OpenAIRE

    Yunes Panahi; Bahram Pishgoo; Amirhossein Sahebkar

    2015-01-01

    Background: Heracleum persicum is a common dietary spice with several traditional medicinal properties important for cardiovascular health including antioxidant, hypolipidemic, and anti-inflammatory effects. This study explored the effects of supplementation with H. persicum fruit on the angiographic findings of patients with minimal coronary artery disease (CAD). Methods: Subjects who were diagnosed with 0.05). Similarly, there was no significant difference between the study groups in t...

  3. Occult sporadic insulinoma:Localization and surgical strategy

    Institute of Scientific and Technical Information of China (English)

    Bassam Abboud; Joe Boujaoude

    2008-01-01

    Insulinomas continue to pose a diagnostic challenge to physicians,surgeons and radiologists alike.Most are intrapancreatic,benign and solitary.Biochemical diagnosis is obtained and imaging techniques to localize lesions continue to evolve.Surgical resection is the treatment of choice.Despite all efforts,an occult insulinoma (occult insulinoma refers to a biochemically proven tumor with indeterminate anatomical site before operation) may still be encountered.New localization preoperative techniques decreases occult cases and the knowledge of the site of the mass before surgery allows to determine whether enucleation of the tumor or pancreatic resection is likely to be required and whether the tumor is amenable to removal via a laparoscopic approach.In absence of preoperative localization and intraoperative detection of an insulinoma,blind pancreatic resection is not recommended.

  4. Probing the Martian atmosphere with MAVEN/IUVS stellar occultations

    Science.gov (United States)

    Gröller, H.; Yelle, R. V.; Koskinen, T. T.; Montmessin, F.; Lacombe, G.; Schneider, N. M.; Deighan, J.; Stewart, A. I. F.; Jain, S. K.; Chaffin, M. S.; Crismani, M. M. J.; Stiepen, A.; Lefèvre, F.; McClintock, W. E.; Clarke, J. T.; Holsclaw, G. M.; Mahaffy, P. R.; Bougher, S. W.; Jakosky, B. M.

    2015-11-01

    The first campaign of stellar occultations with the Imaging Ultraviolet Spectrograph (IUVS) instrument on board of Mars Atmosphere and Volatile EvolutioN (MAVEN) mission was executed between 24 and 26 March 2015. From this campaign 13 occultations are used to retrieve CO2 and O2 number densities in the altitude range between 100 and 150 km. Observations probe primarily the low-latitude regions on the nightside of the planet, just past the dawn and dusk terminator. Calculation of temperature from the CO2 density profiles reveals that the lower thermosphere is significantly cooler than predicted by the models in the Mars Climate Database. A systematically cold layer with temperatures of 105-120 K is seen in the occultations at a pressure level around 7 × 10-6 Pa.

  5. The zero-wall puncture: a novel angiographic puncture technique with substantial benefits

    International Nuclear Information System (INIS)

    Medical education can be busy, exhausting, and stressful, with potential adverse effects on trainees' physical and mental health. Radiology residency is no exception. In addition to increased daily workload and study requirements, Canadian radiology residents are performing a diverse and increasing number of emergent diagnostic examinations after hours. In an attempt to improve resident self-worth and efficiency during angiographic rotations, we investigated the effects of a novel angiographic puncture procedure on various resident lifestyle indexes. Standard techniques for accessing the femoral artery are either the single-wall puncture or double-wall puncture (Seldinger technique). Both of these techniques are widely known and practiced. Following procedure completion, hemostasis must be achieved at the puncture site. This has traditionally required manual compression at the puncture site, which may require 15 to 20 minutes. At our institution the standard policy is that 'whoever makes the puncture, compresses the groin,' also known as 'you broke it, you fix it'. This has prompted our industrious resident complement to develop a novel, previously undescribed, angiographic puncture technique known as the 'zero-wall puncture technique.' Preliminary unpublished results from our institution show that when residents employ the zero-wall puncture technique the attending staff radiologist subsequently both performs the puncture and compresses the groin at the end of the procedure. We investigated the effect of zero-wall puncture on various resident lifestyle indexes. (author)

  6. Hepatic angiographic findings of ruptured hepatocellular carcinoma: 'Sentinel signs' versus extravasation

    International Nuclear Information System (INIS)

    This study retrospectively compared the accuracy of angiographic sentinel signs (sentinel vessels, hypovascular areas, and delayed dots) with extravasation in the diagnosis of ruptured hepatocellular carcinoma (HCC). Sixteen patients diagnosed with HCC between March 2007 and November 2011 were evaluated. Among the patients, we identified 32 HCCs (19 ruptured, 13 unruptured), and assessed all HCCs by hepatic angiography with regard to extravasation, sentinel vessels, hypovascular areas, and delayed dots. We compared the sensitivity and specificity of the sentinel signs with those of the extravasation for the diagnosis of a ruptured HCC. For the angiographic diagnosis of a ruptured HCC, the sensitivity of the sentinel signs (sentinel vessel, 63.2%; hypovascular area, 89.5%; delayed dot, 72.7%) was higher than the sensitivity of extravasation (15.8%). The difference in sensitivity between each sentinel sign and extravasation was statistically significant (sentinel vessel, p = 0.012; hypovascular area, p < 0.001; delayed dot, p 0.039). The specificity of sentinel signs for the diagnosis of ruptured HCC was not statistically different from the specificity of extravasation. Sentinel signs are more accurate than extravasation for the angiographic diagnosis of a ruptured HCC.

  7. Novel 3D MR angiographic findings of neurovascular compressive sites in patients with trigeminal neuralgia

    International Nuclear Information System (INIS)

    Neurovascular compressive sites at the root entry zone of the trigeminal nerve were investigated in 25 patients with trigeminal neuralgia by using the fine three-dimensional (3D) magnetic resonance (MR) angiogram, obtained by a 3D time-of-flight, spoiled gradient-recalled sequence. The characteristic 3D MR angiographic findings of the offending vessels were obtained at the neurovascular compressive sites 19/23 (83%), including intermittent MR signal intensity within the vessels in 14/23 (61%), and unclear margin of the vessels in 5/23 (22%). Those abnormal 3D MR angiographic findings were commonly observed at the site of neurovascular compression in conjunction with moderate degree (grade II) and severe degree (grade III) in 19/20 (95%) of the actual nerve compression by the offending vessels. Abnormal findings with 3D MR angiograms may provide flow-related information to suggest a certain neurovascular compression upon the trigeminal nerve by the offending vessels. Those novel 3D MR angiographic findings may be useful for the diagnosis and decision-making process to execute the microvascular decompression surgery in patients with trigeminal neuralgia. (author)

  8. Evolution of Coronary Flow in an Experimental Slow Flow Model in Swines: Angiographic and Pathological Insights

    Directory of Open Access Journals (Sweden)

    Yupeng Bai

    2015-01-01

    Full Text Available Objective. Pathomechanism of coronary slow flow phenomenon remains largely unclear now. Present study observed the pathological and angiographic evolution in a pig model of coronary slow flow. Methods. Coronary slow flow was induced by repeat coronary injection of small doses of 40 µm microspheres in 18 male domestic pigs and angiographic and pathological changes were determined at 3 hours, 7 days, and 28 days after microspheres injection. Results. Compared to control group treated with coronary saline injection n=6 and baseline level, coronary flow was significantly reduced at 3 hours and 7 days but completely recovered at 28 days after coronary microsphere injection in slow flow group. Despite normal coronary flow at 28 days after microsphere injection, enhanced myocardial cytokine expression, left ventricular dysfunction, adverse remodelling, and ischemia/microembolism related pathological changes still persisted or even progressed from 3 hours to 28 days after coronary microsphere injection. Conclusions. Our results show that this large animal slow flow model could partly reflect the chronic angiographic, hemodynamic, and pathological changes of coronary slow flow and could be used to test new therapy strategies against the slow flow phenomenon.

  9. Angiographically Negative Acute Arterial Upper and Lower Gastrointestinal Bleeding: Incidence, Predictive Factors, and Clinical Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Chae, Eun Young; Myung, Seung Jae; Ko, Gi Young; Gwon, Dong Il; Sung, Kyu Bo [Asan Medical Center, Seoul (Korea, Republic of)

    2009-08-15

    To evaluate the incidence, predictive factors, and clinical outcomes of angiographically negative acute arterial upper and lower gastrointestinal (GI) bleeding. From 2001 to 2008, 143 consecutive patients who underwent an angiography for acute arterial upper or lower GI bleeding were examined. The angiographies revealed a negative bleeding focus in 75 of 143 (52%) patients. The incidence of an angiographically negative outcome was significantly higher in patients with a stable hemodynamic status (p < 0.001), or in patients with lower GI bleeding (p = 0.032). A follow-up of the 75 patients (range: 0-72 months, mean: 8 {+-} 14 months) revealed that 60 of the 75 (80%) patients with a negative bleeding focus underwent conservative management only, and acute bleeding was controlled without rebleeding. Three of the 75 (4%) patients underwent exploratory surgery due to prolonged bleeding; however, no bleeding focus was detected. Rebleeding occurred in 12 of 75 (16%) patients. Of these, six patients experienced massive rebleeding and died of disseminated intravascular coagulation within four to nine hours after the rebleeding episode. Four of the 16 patients underwent a repeat angiography and the two remaining patients underwent a surgical intervention to control the bleeding. Angiographically negative results are relatively common in patients with acute GI bleeding, especially in patients with a stable hemodynamic status or lower GI bleeding. Most patients with a negative bleeding focus have experienced spontaneous resolution of their condition.

  10. GRAS radio occultation on-board of Metop

    Science.gov (United States)

    von Engeln, A.; Andres, Y.; Marquardt, C.; Sancho, F.

    2011-01-01

    The GRAS radio occultation instrument is flying on Metop-A and belongs to the EPS (EUMETSAT Polar System). GRAS observes GPS satellites in occultation. Within this work, validation of GRAS closed-loop bending angle data against co-located ECMWF profiles extracted from model fields and occultations from the COSMIC constellation of radio occultation instruments is shown. Results confirm the high data quality and robustness, where GRAS shows lower bending angle noise against ECMWF than COSMIC and in terms of occultations per day, one GRAS ≈ two COSMIC satellites. This is partly due to the operational setup of EPS. For the investigation we focus on two observation periods where updates in the ECMWF (March 2009) and COSMIC processing (October 2009) have improved the statistics further. Bending angles biases agree to within 0.5% against ECMWF and to within 0.1% against COSMIC after the updates for altitudes between 8 and 40 km. In addition, we also analyze the impact of the Metop orbit processing on the derived GRAS bending angle data, where different GPS and Metop orbit solutions are analyzed. Results show that a batch based orbit processing would improve in particular the bending angle bias behavior at higher altitudes. Requirements for the operational processing of GRAS data are briefly outlined, options to ease the use of other positioning system satellites in the near future are discussed. A simplified analysis on the observation of several of these systems, e.g. GPS and Galileo, from one platform shows that about 16% of occultations are found within 300 km, ±3 h, thus providing similar information. A constellation of 2 GRAS like instruments would have only about 10% close-by.

  11. Deriving Saturn's Zonal Winds from Cassini Radio Occultations

    Science.gov (United States)

    Flasar, F. Michael; Schinder, Paul J.

    2015-11-01

    Tracking cloud features from visible images have provided detailed maps of the meridional variation of the mean zonal winds on the giant planets, including Saturn. Filters at different wavelengths can provide information on the vertical structure of the zonal winds, but that is approximate, and the altitudes of winds observed with a given filter generally vary with location, because cloud heights do. Radio occultations provide vertical profiles of refractivity, pressure, and temperature vs. altitude. Zonal winds can be derived from the assumption of gradient wind balance, which relates the zonal wind to the change of geopotential height with latitude along an isobar. Occultations have the advantage that vertical profiles of winds can be obtained in the troposphere and stratosphere. There are, however, complicating factors. In general, the meridional distribution of occultation soundings is limited and unevenly distributed. Moreover, one needs to know the geometry of the occulting atmosphere to correctly account for the path of the refracted radio signal. The zonal winds matter, because they distort isobaric surfaces. For example, an inversion that includes Saturn's oblateness from uniform rotation, based on the Voyager System III period, would yield equatorial temperature profiles that are shifted by ~ 2 K relative to one that also includes the differential rotation associated with the cloud-tracked zonal winds. In retrieving vertical profiles of atmospheric variables from occultation soundings, one also needs an additional symmetry assumption to make the inversions tractable. Typically one uses the zonal winds based on cloud-tracking studies, and assumes they are axisymmetric and barotropic, so that both the gravitational and centrifugal forces are derivable from a potential, and the surfaces of constant geopotential height, pressure, and temperature coincide. This forms the basis for an iterative approach. The pressures and temperatures so retrieved from the

  12. The angiographic features of cerebral ischemia due to Takayasu arteritis%大动脉炎性脑缺血的脑血管造影特征分析

    Institute of Scientific and Technical Information of China (English)

    刁士元

    2010-01-01

    Objective To explore the angiographic features of c cerebral ischemia due to Takayasu arteritis. Methods The clinical data and angiographic findings of twenty patients with Takayasu rteritis were analyzed retrospectively. Two experienced radiologists read all the angiographic images of the patients with a double-blind method, then discussed together, and finally formed an unanimous interpretation. Results According to the Lupi-Herrera classification, 17 of 20 patients were type Ⅰ and the rest 3 were type Ⅲ on angiograms. The affected arteries mainly included subclavian artery (19 patients), carotid artery (17 patients), vertebral artery (12 patients), and brachiocephalic trunk (6 patients). Conclusions Cerebral angiography can accurately and effectively assess the vascular status in patients with cerebral ischemia due to Takayasu arteritis. It is beneficial in the diagnosis of Takayasu arteritis..%目的 探讨大动脉炎性脑缺血的脑血管造影特征.方法 回顾性分析20例大动脉炎性脑缺血患者的病例资料及脑血管造影结果.脑血管造影资料由有经验的介入放射学医师按盲法对比进行分析,然后共同讨论并达成一致意见.结果 20例中,经血管造影按Lupi-Herrera 综合分型法Ⅰ型17例,Ⅲ型3例.主要受累动脉包括锁骨下动脉19例,颈动脉17例,椎动脉12例,头臂干6例.结论脑血管造影可准确、有效的评估大动脉炎性脑缺血患者的血管情况,有利于大动脉炎的诊断.

  13. Three-dimensional CT angiographic assessment of pelvic and lower-extremity occlusive disease using single detector-row and multidetector-row CT scanners

    International Nuclear Information System (INIS)

    Three-dimensional CT angiography (3D-CTA) using a single detector-row CT (SDCT) scanner has become an important technique in the evaluation of the vascular system. A multidetector-row CT (MDCT) scanner, that is, a more advanced CT scanner which can acquire up to four channels of data simultaneously, has been recently introduced. With the use of this robust CT scanner, it is expected that more efficient 3D-CTAs will be obtained thanks to the superior temporal and spatial resolution provided by this technology. The purpose of this study was to assess the usefulness of 3D-CTA reconstructed from the data sets obtained using both SDCT and MDCT scanners, and to evaluate new software which was originally developed for the assessment of vascular wall pathology and vessel tortuosity. Twenty patients with pelvic arterial occlusive disease underwent 3D-CTA using a SDCT scanner. For stenoses and occlusions, 3D-CTA had a sensitivity of 93%, and a specificity of 89% as compared to digital subtraction angiography. Long anatomical range 3D-CT angiographic evaluations, from the pelvic artery to the lower legs, were performed in five patients with peripheral arterial occlusive disease using an MDCT scanner. All significant stenoses and occlusions were nicely depicted by the 3D-CTAs using the MDCT scanner. A new method for semiautomatically produced, curvedplanar reconstructed images along the vessel length based on a virtual CT endoscopic technique (CEV-CPR method) provided smoothly reformatted longitudinal images of the vessel. Using a new technique for assessing vessel tortuosity, we were able to quantitatively evaluate vessel tortuosity by calculating vessel curvature. In conclusion, 3D-CTA using SDCT and MDCT scanners and newly developed software provided useful qualitative and quantitative information concerning vascular pathology in patients with pelvic and lower-extremity occlusive disease. (author)

  14. Forthcoming Occultations of Astrometric Radio Sources by Planets

    Science.gov (United States)

    L'vov, Victor; Malkin, Zinovy; Tsekmeister, Svetlana

    2010-01-01

    Astrometric observations of radio source occultations by solar system bodies may be of large interest for testing gravity theories, dynamical astronomy, and planetary physics. In this paper, we present an updated list of the occultations of astrometric radio sources by planets expected in the coming years. Such events, like solar eclipses, generally speaking can only be observed in a limited region. A map of the shadow path is provided for the events that will occurr in regions with several VLBI stations and hence will be the most interesting for radio astronomy experiments.

  15. An occultation of the inner Seyfert nucleus of NGC 4151

    International Nuclear Information System (INIS)

    The brightness of the unresolved nucleus of NGC 4151 was monitored over five months in 1983. Variations of ≅ 0.1 mag/day were observed in the U-band and no significant variation was found of the -OIII] 5007 A emission line. However, an event that was observed on the nights of the 10/11 and 11/12 February 1983 in the continuum around 5672 A has all the characteristics of an occultation. It is proposed that an inner synchrotron nucleus of ≅ 3 a.u. diameter was occulted by an opaque cloud ≅ 6 a.u. across on those two nights

  16. [Pitfalls in the diagnosis of occult elbow fractures in children].

    Science.gov (United States)

    Courvoisier, A; Calvelli, N; Bourgeois, E; Eid, A; Griffet, J

    2016-08-01

    Elbow injuries are frequent but occult fractures are difficult to diagnose on x-rays. However, any delay in the diagnosis may severely impair the prognosis of some fractures. Simple tips may help the clinician read x-rays properly and avoid the classical pitfalls of elbow injuries in children. The chronology of appearance of ossification nuclei around the elbow is important to distinguish normal features from abnormality. Drawing simple geometric constructions on the x-rays may clarify most occult elbow fractures in children. PMID:27345552

  17. Presentation of Axillary Metastases from Occult Breast Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Xin Wang

    2007-01-01

    Axillary presentation from occult breast cancer is uncommon and continues to be a diagnostic and therapeutic challenge to physicians.Once the diagnosis of adenocarcinoma metastatic to an axillary lymph node has been confirmed,a preoperative workup should be done.The current experience is based on several relatively small retrospective reviews and case reports.It is difficult to determine the best management of occult breast cancer.However,treatmenl of axillary Iymph node dissection is recommended for local control and complete staging information.Treatment of breast should be a choice between breast conservation with whole-breast radiotherapy and mastectomy.Adjuvant systemic treatment should be offered.

  18. YOHKOH remnants: partially occulted flares in hard X-rays

    OpenAIRE

    M. Tomczak

    2009-01-01

    Flares being partially occulted by the solar limb, are the best reservoir of our knowledge about hard X-ray loop-top sources. Recently, the survey of partially occulted flares observed by the RHESSI has been published (Krucker & Lin 2008). The extensive YOHKOH database still awaits such activities. This work is an attempt to fill this gap. Among from 1286 flares in the YOHKOH Hard X-ray Telescope Flare Catalogue, for which the hard X-ray images had been enclosed, we identified 98 events that ...

  19. Status of the Transneptunian Automated Occultation Survey (TAOS II)

    Science.gov (United States)

    Lehner, Matthew J.; Wang, Shiang Yu; Reyes-Ruiz, Mauricio; Chu, You Hua; Lee, William; Zhang, Zhi Wei; Cook, Kem H.; Norton, Timothy; Szentgyorgyi, Andrew; Alcock, Charles

    2015-11-01

    The Transneptunian Automated Occultation Survey (TAOS II) will aim to detect occultations of stars by small (~1 km diameter) objects in the Kuiper Belt and beyond. Such events are very rare (field of view and a high speed camera comprising CMOS imagers, the survey will monitor 10,000 stars simultaneously with all three telescopes at a nominal readout cadence of 20 Hz. Construction of the site began in the fall of 2013. We present here an update on the status of the TAOS II survey, including the site development, camera fabrication, and project schedule.

  20. Generation of a Bending Angle Radio Occultation Climatology (BAROCLIM and its use in radio occultation retrievals

    Directory of Open Access Journals (Sweden)

    B. Scherllin-Pirscher

    2014-08-01

    Full Text Available In this paper, we introduce a bending angle radio occultation climatology (BAROCLIM based on Formosat-3/COSMIC (F3C data. This climatology represents the monthly-mean atmospheric state from 2006 to 2012. Bending angles from radio occultation (RO measurements are obtained from the accumulation of the change in the raypath direction of Global Positioning System (GPS signals. Best quality of these near-vertical profiles is found from the middle troposphere up to the mesosphere. Beside RO bending angles we also use data from the Mass Spectrometer and Incoherent Scatter Radar (MSIS model to expand BAROCLIM in a spectral model, which (theoretically reaches from the surface up to infinity. Due to the very high quality of BAROCLIM up to the mesosphere, it can be used to detect deficiencies in current state-of-the-art analysis and reanalysis products from numerical weather prediction (NWP centers. For bending angles derived from European Centre for Medium-Range Weather Forecasts (ECMWF analysis fields from 2006 to 2012, e.g., we find a positive bias of 0.5% to % at 40 km, which increases to more than 2% at 50 km. BAROCLIM can also be used as a priori information in RO profile retrievals. In contrast to other a priori information (i.e., MSIS we find that the use of BAROCLIM better preserves the mean of raw RO measurements. Global statistics of statistically optimized bending angle and refractivity profiles also confirm that BAROCLIM outperforms MSIS. These results clearly demonstrate the utility of BAROCLIM.

  1. Theoretical performance of solar coronagraphs using sharp-edged or apodized circular external occulters

    Science.gov (United States)

    Aime, C.

    2013-10-01

    Context. This study focuses on an instrument able to monitor the corona close to the solar limb. Aims: We study the performance of externally occulted solar coronagraphs. We compute the shape of the umbra and penumbra produced by the occulter at the entrance aperture of the telescope and compare levels of rejection obtained for a circular occulter with a sharp or smooth transmission at the edge. Methods: We show that the umbral pattern in an externally occulted coronagraph can be written as a convolution product between the occulter diffraction pattern and an image of the Sun. We then focus on the analysis to circular symmetric occulters. We first derive an analytical expression using two Lommel series for the Fresnel diffraction pattern produced by a sharp-edged circular occulter. Two different expressions are used for inside and outside the occulter's geometric shadow. We verify that a numerical approach that directly solves the Huygens-Fresnel integral gives the same result. This suggests that the numerical computation can be used for a circular occulter with any variable transmission. Results: With the objective of observing the solar corona a few minutes from limb, a sharp-edged circular occulter of a few meters cannot produce an umbra darker than 10-4 of the direct sunlight. The same occulter, having an apodization zone of a few percent of the diameter (3 cm for a 1.5 m occulter), darkers the umbra down to 10-8 of the direct sunlight for linear transmission and to 10-12 for Sonine or cosine bell transmissions. An investigation for an apodized occulter with manufacturing defaults is quickly performed. Conclusions: It has been possible to numerically demonstrate the large superiority of apodized circular occulters with respect to the sharp-edged ones. These occulters allow the theoretical observation of the very limb-close corona with not yet obtained contrast ratios.

  2. Oh Glorious Geometry: Eclipses, Transits, and Occultations

    Science.gov (United States)

    Sinclair, R. M.

    2016-01-01

    Astronomical objects are like a grand clockwork in the sky; they follow steady patterns in time. However, these bright objects we see are not just points of light but have finite dimensions and thus can get in each other's way. As a result, some stars puzzle us by brightening or dimming, or the Sun can frighten us by going out unexpectedly when something else blocks its light. There is nothing unusual about these eclipses, occultations, or transits—they are demonstrations of simple physics—and we take some for granted, like the rotation of Earth moving us into darkness each night. The periodic dimming of a bright star worried mankind for millennia and helped give astronomy a shove. And unexpected events, like a solar or lunar eclipse, can inspire awe and change the course of history. Now that we can observe through telescopes and travel by proxy throughout the solar system, we find the universe is rife with shadow and light shows. Those taking place within our solar system have been useful to astronomy (like the recent transits of Venus or the ever-present eclipses of the Jovian satellites), and were of considerable popular interest, allowing us to think beyond the confines of Earth. Now we detect distant exoplanets transiting their parent stars, announcing the presence of other solar systems in our corner of the Galaxy and changing the discussion about life elsewhere in the universe from mere speculation to plausible possibility. Distant galaxies can make visible ever-further galaxies by forming Einstein rings, allowing us to see behind them and make the structure of the universe more evident. This paper will discuss these phenomena, from those visible easily on Earth to those that can now be seen for the first time from probes in space. We will also discuss how this has expanded popular knowledge of the universe we live in. This paper is illustrated by a number of examples ranging from eclipses and transits throughout the solar system and the nearby stars to

  3. Is Occult Obscure Gastrointestinal Bleeding a Definite Indication for Capsule Endoscopy? A Retrospective Analysis of Diagnostic Yield in Patients with Occult versus Overt Bleeding

    OpenAIRE

    Ikue Watari; Shiro Oka; Shinji Tanaka; Makoto Nakano; Taiki Aoyama; Shigeto Yoshida; Kazuaki Chayama

    2013-01-01

    Background/Aim. Usefulness of capsule endoscopy (CE) for diagnosing small-bowel lesions in patients with obscure gastrointestinal bleeding (OGIB) has been reported. Most reports have addressed the clinical features of overt OGIB, with few addressing occult OGIB. We aimed to clarify whether occult OGIB is a definite indication for CE. Methods. We retrospectively compared the cases of 102 patients with occult OGIB and 325 patients with overt OGIB, all having undergone CE. The diagnostic yield o...

  4. Occultations of stars by solar system objects. VIII - Occultations of catalog stars by asteroids, planets, Titan, and Triton in 1990 and 1991

    Science.gov (United States)

    Wasserman, L. H.; Bowell, E.; Millis, R. L.

    1990-01-01

    Predictions are given for occultations of catalog stars by asteroids, planets, Titan, and Triton in 1990 and 1991. The predictions are based on a computerized comparison of the occulting bodies' ephemerides and nine major star catalogs. The search is complete for all numbered asteroids whose angular diameters exceed 0.08 arcsec during the search years. Preliminary ground tracks are shown for the more favorable occultations.

  5. Collagen vascular disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001223.htm Collagen vascular disease To use the sharing features on this page, ... were previously said to have "connective tissue" or "collagen vascular" disease. We now have names for many of many ...

  6. Heart and vascular services

    Science.gov (United States)

    ... branch of medicine that focuses on the cardiovascular system. ... Circulatory system; Vascular system; Cardiovascular system ... to diagnose, monitor or treat diseases of the circulatory and vascular system include: Cardiac CT for calcium scoring Cardiac MRI ...

  7. The Precise Determination of Vascular Lumen and Stent Diameters: Correlation Among Calibrated Angiography, Intravascular Ultrasound, and Pressure-Fixed Specimens

    International Nuclear Information System (INIS)

    Purpose: Luminal diameters measured in vivo by calibrated-catheter angiography and by intravascular ultrasound were correlated with those obtained from pressure-fixed histologic cross-sections to determine the accuracy of both methods. Methods: Angiographic and endosonographic diameter measurements were performed in the center of stents placed in the iliac arteries of 10 miniature pigs and were compared with luminal and stent diameters in postmortem, pressure-fixed, histologic cross-sections from identical locations. Results: Compared with histologic diameters, magnification-corrected angiographic measurements still magnified vascular luminal diameters by 0.7 ± 0.71 mm (r= 0.41, Pearson; p 0.5, Wilcoxon, matched pairs). Similarly, stent diameters correlated well between endosonographic and histologic measurements (r= 0.91; p= 0.002), and less well between angiographic and histologic diameters (r= 0.62; p= 0.002). Conclusion: Since calibrated angiography still overestimates vascular lumina, endosonography is the preferred technique for accurate in vivo measurements

  8. Radio occultation bending angle anomalies during tropical cyclones

    Directory of Open Access Journals (Sweden)

    R. Biondi

    2011-02-01

    Full Text Available The tropical deep convection affects the radiation balance of the atmosphere changing the water vapor mixing ratio and the temperature of the upper troposphere lower stratosphere. The aim of this work is to better understand these processes and to investigate if severe storms leave a significant signature in radio occultation profiles in the tropical tropopause layer. Using tropical cyclone best track database and data from different GPS radio occultation missions (COSMIC, GRACE, CHAMP, SACC and GPSMET, we selected 1194 profiles in a time window of 3 h and a space window of 300 km from the eye of the cyclone. We show that the bending angle anomaly of a GPS radio occultation signal is typically larger than the climatology in the upper troposphere and lower stratosphere and that a double tropopause during deep convection can easily be detected using this technique. Comparisons with co-located radiosondes, climatology of tropopause altitudes and GOES analyses are also shown to support the hypothesis that the bending angle anomaly can be used as an indicator of convective towers. The results are discussed in connection to the GPS radio occultation receiver which will be part of the Atomic Clock Ensemble in Space (ACES payload on the International Space Station.

  9. Occult hepatitis B among Iranian hepatitis C patients

    Directory of Open Access Journals (Sweden)

    Ahmad shavakhi

    2009-02-01

    Full Text Available

    • BACKGROUND: Occult hepatitis B is defined as presence of HBV DNA in tissue or serum without hepatitis B surface antigen. The aim of this study is to determine frequency of occult hepatitis B among hepatitis C patients in Tehran and compare the route of transmission and liver enzymes between positive and negative HBV DNA patients.
    • METHODS: In a cross sectional study, serum of 103 hepatitis C cases (79.6% men and 20.4% women were analyzed for s, x and core genes via a nested polymerase chain reaction technique.
    • RESULTS: HBV DNA was detectable in serum of 20 patients (19.4%. No significant difference in age, sex and route of transmission were seen in HBV DNA positive and negative patients. In HBV DNA positive and negative groups, mean of AST was 73, 47 (p < 0.05 and mean of ALT was 76 and 36 respectively (p < 0.05.
    • CONCLUSION: Occult hepatitis B was observed in a considerable number of hepatitis C patients in Tehran. It was associated with elevation in liver enzyme but was not related to route of transmission.
    • KEY WORD: Occult hepatitis B, hepatitis C, cirrhosis.

  10. Counseling the Occult-Involved Student: Guidelines and Suggestions.

    Science.gov (United States)

    Carmichael, Karla D.

    1993-01-01

    Contends that counselors working with public school students needs to be aware of the four main levels of involvement in the occult (fun-and-games, dabblers, serious involvement, and criminal involvement). Each of the four levels is described, warning signs are identified, and the counselor's role is explained as one of support and prevention. (NB)

  11. Occult Dirofilariosis in Dogs of North Eastern Region in India

    Directory of Open Access Journals (Sweden)

    Sonjoy Kumar-Borthakur

    2015-10-01

    Full Text Available Background: The North Eastern Region in India is endemic for canine heartworm disease but in clinics accurate diagnosis is some times difficult. The aim of the present study was to determine the prevalence of occult infections for heartworm disease in canine in two geographical regions of North Eastern India.Methods: A total of 782 numbers of three categories of dogs namely, working dogs of military and paramilitary forces, pet dogs and stray dogs were screened for the presence of heartworm infection from August 2011 to July, 2012 in Guwahati (Assam and Aizawl (Mizoram. Conventional, immunological and molecular techniques were followed for this epidemiological study. The criteria to determine the occult heartworm cases were based on the dif­ferences between heartworm positive cases in PCR test and antigen ELISA test.Results: The findings revealed an overall 22.69 percent occult case. The working dogs had highest prevalence (60% followed by pet (29.16% and stray dogs (17.75%.Conclusion: The highest percentage of occult heartworm infection was present in working dogs maintained under military or paramilitary forces. 

  12. Pulmonary tumor embolism syndrome from occult colonic adenocarcinoma

    OpenAIRE

    Heithaus, Robert Evans; Hitchcock, Michael A.; Guileyardo, Joseph M.

    2013-01-01

    Pulmonary tumor embolism syndrome is a rare phenomenon that can occur in patients who have an occult neoplasm that metastasizes. We describe a case of an elderly woman with an undiagnosed colon cancer who suffered from respiratory distress and compromised pulmonary blood flow from micrometastasis in the pulmonary arteries.

  13. How to Prevent Vascular Disease

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  14. OCCULTATION OBSERVATIONS OF SATURN'S B RING AND CASSINI DIVISION

    International Nuclear Information System (INIS)

    The outer edge of Saturn's B ring is strongly affected by the nearby 2:1 inner Lindblad resonance of Mimas and is distorted approximately into a centered elliptical shape, which at the time of the Voyager 1 and 2 encounters was oriented with its periapse toward Mimas. Subsequent observations have shown that the actual situation is considerably more complex. We present a complete set of historical occultation measurements of the B-ring edge, including the 1980 Voyager 1 and 1981 Voyager 2 radio and stellar occultations, the 1989 occultation of 28 Sgr, two independently analyzed occultations observed with the Hubble Space Telescope in 1991 and 1995, and a series of ring profiles from 12 diametric (ansa-to-ansa) occultations observed in 2005, using the Cassini Radio Science Subsystem (RSS). After making an approximate correction for systematic errors in the reconstructed spacecraft trajectories, we obtain orbit fits to features in the rings with rms residuals well under 1 km, in most cases. Fits to the B-ring edge in the RSS data reveal a systematic variation in the maximum optical depth at the very edge of the ring as a function of its orbital radius. We compare the B-ring measurements to an m = 2 distortion aligned with Mimas, and show that there have been substantial phase shifts over the past 25 years. Finally, we present freely precessing equatorial elliptical models for 16 features in the Cassini Division. The inner edges of the gaps are generally eccentric, whereas the outer edges are nearly circular, with ae < 0.5 km.

  15. Treatment outcomes of occult breast carcinoma and prognostic analyses

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; ZHANG Ye-fan; WANG Xin; WANG Jian; YANG Xue; GAO Yin-qi; FANG Yi

    2013-01-01

    Background The surgical management of occult breast cancer is controversial.We compared the outcomes of different treatments of occult breast cancer and evaluated the potential prognostic factors for overall survival and recurrence.Methods We retrospectively reviewed 77 patients who presented to our hospital from 1968 to 2011 with a diagnosis of occult breast cancer.Patients were divided into three groups:42 patients (63%) were treated with modified radical mastectomy+axillary lymph node dissection (ALND),16 patients (24%) were treated with ALND+postoperative radiotherapy,and 9 patients (13%) with only ALND.Survival analyses were undertaken to compare the efficacy of these three treatments.Results Of the 77 patients with occult breast cancer,2 patients were lost to follow-up and 8 patients refused surgical treatment:67 patients (90.4%) were included in this analysis.The median follow-up was 62.2 (0.6-328.0)months.Kaplan-Meier analyses showed no significant difference in overall survival and recurrence-free survival between the three groups (P=0.494 and 0.397,respectively).The prevalence of local recurrence was 11.9% for the mastectomy+ALND,18.8% for ALND+radiotherapy,and 11.1% for ALND-only groups,and those for distant recurrence were 2.4%,12.5%,and 11.1%,respectively.Compared with progesterone receptor-negative subjects,progesterone receptor-positive patients had better overall survival and lower recurrence rates (P=0.057 and 0.062,respectively).Conclusions There was no significant difference in outcomes between mastectomy and breast-preserving surgery.Expression of the progesterone receptor should be taken into account when evaluating the prognosis of occult breast cancer.

  16. Laboratory Verification of Occulter Contrast Performance and Formation Flight

    Science.gov (United States)

    Sirbu, Dan

    2014-01-01

    Direct imaging of an exo-Earth is a difficult technical challenge. First, the intensity ratio between the parent star and its dim, rocky planetary companion is expected to be ten billion times. Additionally, for a planetary companion in the habitable zone the angular separation to the star is very small, such that only nearby stars are feasible targets. An external occulter is a spacecraft that is flown in formation with the observing space telescope and blocks starlight prior to the entrance pupil. Its shape must be specially designed to control for diffraction and be tolerant of errors such as misalignment, manufacturing, and deformations. In this dissertation, we present laboratory results pertaining to the optical verification of the contrast performance of a scaled occulter and implementation of an algorithm for the alignment of the telescope in the shadow of the occulter. The experimental testbed is scaled from space dimensions to the laboratory by maintaining constant Fresnel numbers while preserving an identical diffraction integral. We present monochromatic results in the image plane showing contrast better than 10 orders of magnitude, consistent with the level required for imaging an Exo-earth, and obtained using an optimized occulter shape. We compare these results to a baseline case using a circular occulter and to the theoretical predictions. Additionally, we address the principal technical challenge in the formation flight problem through demonstration of an alignment algorithm that is based on out-of-band leaked light. Such leaked light can be used a map to estimate the location of the telescope in the shadow and perform fine alignment during science observations.

  17. Utility of the arteriography in vascular trauma

    International Nuclear Information System (INIS)

    It is re-examined in a retrospective way the clinical information of 320 patients handled during a period of 13 months, to determine how frequent it is identified arterial injuries clinically silent through routine arteriography, and with which frequency these injuries are serious enough to require surgical handling. The study of the angiographic diagnosis was done to find out if there were one or more of the following clinical findings: stable haematoma, deficit of pulse, bleeding record, deficit of perispheric nerve, deficit of central nerve, heart-blow, haematoma or pulsatile mass, thrill, widen mediastinum or proximity to an important neurovascular package. A total of 595 cases were studied. In 128 occasions the arteriography was done when the patient showed abnormal clinical findings, detecting 47 injuries in 37 patients who required surgery or endovascular treatment. The anatomical proximity was the indication to evaluate 467 cases, detecting 20 injuries, four of which required surgery. In asymptomatic patients, the probability to detect vascular injury and required surgery, was significantly less than in symptomatic patients (p < 0.0000001 and p < 0.000045 respectively). In case of trauma, the need of an arteriography is based on the clinical findings, in which absence; the routine diagnostic arteriography detects fewer injuries, and occasionally identifies important injuries that require surgery. The results of this study suggest that, in asymptomatic patients the routine usage of the arteriography is given up and should be practiced selectively only on symptomatic patients

  18. Crohn's disease and massive lower gastrointestinal bleeding: angiographic appearance and two case reports

    International Nuclear Information System (INIS)

    Massive lower gastrointestinal bleeding is described in two patients with Crohn's disease. In case 1, extravasation of contrast material from the ileal branch of the ileocolic artery was seen during selective angiography. In case 2, results of an in vitro labeled 99Tc pyrophosphate red blood cell scan localized bleeding to the ileum. In both cases, medical management was unsuccessful, and surgical resection of the affected bowel was required to stop the bleeding. Angiographic appearance of Crohn's disease is discussed, and a review of the literature of this unusual feature of Crohn's disease is presented. 16 references

  19. Wave optics-based LEO-LEO radio occultation retrieval

    Science.gov (United States)

    Benzon, Hans-Henrik; Høeg, Per

    2016-06-01

    This paper describes the theory for performing retrieval of radio occultations that use probing frequencies in the XK and KM band. Normally, radio occultations use frequencies in the L band, and GPS satellites are used as the transmitting source, and the occultation signals are received by a GPS receiver on board a Low Earth Orbit (LEO) satellite. The technique is based on the Doppler shift imposed, by the atmosphere, on the signal emitted from the GPS satellite. Two LEO satellites are assumed in the occultations discussed in this paper, and the retrieval is also dependent on the decrease in the signal amplitude caused by atmospheric absorption. The radio wave transmitter is placed on one of these satellites, while the receiver is placed on the other LEO satellite. One of the drawbacks of normal GPS-based radio occultations is that external information is needed to calculate some of the atmospheric products such as the correct water vapor content in the atmosphere. These limitations can be overcome when a proper selected range of high-frequency waves are used to probe the atmosphere. Probing frequencies close to the absorption line of water vapor have been included, thus allowing the retrieval of the water vapor content. Selecting the correct probing frequencies would make it possible to retrieve other information such as the content of ozone. The retrieval is performed through a number of processing steps which are based on the Full Spectrum Inversion (FSI) technique. The retrieval chain is therefore a wave optics-based retrieval chain, and it is therefore possible to process measurements that include multipath. In this paper simulated LEO to LEO radio occultations based on five different frequencies are used. The five frequencies are placed in the XK or KM frequency band. This new wave optics-based retrieval chain is used on a number of examples, and the retrieved atmospheric parameters are compared to the parameters from a global European Centre for Medium

  20. Occultation studies of the Solar system. Semiannual status report, 1 July-31 December 1986

    International Nuclear Information System (INIS)

    The planetary occultation program began at Lowell Observatory in 1973 with a worldwide campaign to observe mutual occultations and eclipses of the Galilean Satellites. Then the temperature profile of the Martian atmosphere was measured from data taken during the occultation of epsilon Geminorum, the Rings of Uranus were discovered as they occulted SAO 158687, and the dimensions of Pallas were measured when that minor planet occulted SAO 85009. In 1979 the present grant was initiated, providing funds for portable photometric instrumentation used to observe occultations by asteroids as well as by Uranus and Neptune. Software for predicting occultations of catalog stars by asteroids, planets, and comets was written in 1983. Lowell currently provides most of the available predictions for asteroid occultations. Realizing in 1983 that the lack of a high-quality astrometric telescope dedicated to occultation work was limiting progress, an 18-inch, F/8 lens was acquired and adapted to an existing mounting at Lowell. Although acquisition of the lens and implementation of the new telescope has been accomplished primarily with non-grant funds, the instrument makes a major contribution to occultation research

  1. Error analysis for mesospheric temperature profiling by absorptive occultation sensors

    Directory of Open Access Journals (Sweden)

    M. J. Rieder

    Full Text Available An error analysis for mesospheric profiles retrieved from absorptive occultation data has been performed, starting with realistic error assumptions as would apply to intensity data collected by available high-precision UV photodiode sensors. Propagation of statistical errors was investigated through the complete retrieval chain from measured intensity profiles to atmospheric density, pressure, and temperature profiles. We assumed unbiased errors as the occultation method is essentially self-calibrating and straight-line propagation of occulted signals as we focus on heights of 50–100 km, where refractive bending of the sensed radiation is negligible. Throughout the analysis the errors were characterized at each retrieval step by their mean profile, their covariance matrix and their probability density function (pdf. This furnishes, compared to a variance-only estimation, a much improved insight into the error propagation mechanism. We applied the procedure to a baseline analysis of the performance of a recently proposed solar UV occultation sensor (SMAS – Sun Monitor and Atmospheric Sounder and provide, using a reasonable exponential atmospheric model as background, results on error standard deviations and error correlation functions of density, pressure, and temperature profiles. Two different sensor photodiode assumptions are discussed, respectively, diamond diodes (DD with 0.03% and silicon diodes (SD with 0.1% (unattenuated intensity measurement noise at 10 Hz sampling rate. A factor-of-2 margin was applied to these noise values in order to roughly account for unmodeled cross section uncertainties. Within the entire height domain (50–100 km we find temperature to be retrieved to better than 0.3 K (DD / 1 K (SD accuracy, respectively, at 2 km height resolution. The results indicate that absorptive occultations acquired by a SMAS-type sensor could provide mesospheric profiles of fundamental variables such as temperature with

  2. Comparison of angiographic and CT findings between patients with multi-infarct dementia and those with dementia due to primary neuronal degeneration

    International Nuclear Information System (INIS)

    The CT and angiographic appearances in multi-infarct dementia have been compared with those of primary neuronal degeneration. It was possible to make a CT or angiographic diagnosis of multi-infarct dementia in about 40% of patients diagnosed by the ischaemic scoring of Hachinski et al. (orig.)

  3. Comparison and optimization of three-dimensional MR angiographic techniques for evaluation of the intracranial circulation

    International Nuclear Information System (INIS)

    Time-of-flight MR angiographic techniques have various clinical applications. This study examined potential methods of overcoming limitations of inflow techniques and compared the results of these methods under equivalent imaging conditions. Axial three-dimensional (3D) intracranial datasets of equivalent volumes were obtained in 20 volunteers with four optimized MR angiographic techniques: single thick-volume, 64-partition 3D Fourier transform (FT), serial thin-volume, 16-partition 3DFT, serial-section 2DFT, and interleaved phase-sensitive subtraction. Examinations were performed on a 1.5-T system with a transmit/receive head coil and 10-mT/m gradient capability. Maximum-intensity profile postprocessing was then performed. Comparison was made of small-vessel resolution, venous anatomy, extent of flow-void gaps, motion artifacts, and time of acquisition. Thin-section and phase-sensitive techniques provide improved imaging of slow flow (e.g., venous anatomy) in the intracranial circulation as compared to a standard single-volume 3DFT technique. However, for visualization of the more proximal arterial system, the lack of venous overlap in the single-volume 3DFT method remains advantageous

  4. The availability of appropriately fitting personal protective aprons and jackets for angiographic and interventional radiology personnel

    International Nuclear Information System (INIS)

    Purpose: This study explored the availability of personal protective equipment, lead or lead-free aprons or jackets, in angiographic and interventional radiology suites in the Republic of Ireland with a focus on the sizes available, appropriateness of fit and purchasing practices. Methods: All centres providing an angiographic or interventional radiology service in the Republic of Ireland were invited to participate with data being collected by means of a postal questionnaire exploring the above issues. Results: The mean number of aprons or jackets available across the centres who responded to the survey was 18.4 with the majority of these, 72%, being medium or large in size. Clinical specialists in three centres identified that there were insufficient aprons or jackets sized extra small or extra large within their departments and only one centre had a purchasing policy in place where individual staff were assigned a personal apron or jacket. Conclusion: Ill-fitting aprons or jackets will reduce the shielding provided to certain body regions by personal protective equipment. The use of over-sized aprons or jackets by staff is of particular concern based on the potential for inadvertent exposure to tissues where cancers may potentially be induced due to poor armhole fit. It is important to carefully consider purchasing practices and range of personal protective equipment sizes available in order to ensure that all staff receive the greatest possible protection from occupational radiation exposure

  5. Development of a Portable Training Tool for Simulating Visceral Angiographic Procedures for Beginners

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the usefulness of a tool that we developed to simulate performance of visceral angiography to train beginners in the field of splanchnic angiography. Seven residents and two fellows who were rotating within the Division of Interventional Radiology at our institution between June and August 2008 participated in the evaluation of this tool. They had no experience in performing visceral angiography as an operator. Time for selection of arterial branches arising from the celiac axis on the model was measured before and after training. After such training, the participants performed actual visceral angiography as an operator with instructors beside them. Success of the trainees in selecting visceral arterial branches was evaluated in these real-life cases. In the first test using the model, seven of nine trainees (77.8%) succeeded in selecting all required arteries, while the remaining two failed to select all required arteries. After training using the model, all trainees succeeded in selecting all required arteries just before the actual angiographic study. In the actual angiography, the catheter was successfully inserted from the femoral artery and advanced to the superior mesenteric, celiac, splenic, common hepatic, gastroduodenal, and right and left hepatic arteries by all trainees with only two exceptions. In conclusion, this tool is helpful for training beginners in visceral angiographic procedures.

  6. Relationship between scintigraphic probability and angiographic certainty in acute pulmonary embolism

    International Nuclear Information System (INIS)

    Objective: To determine if the angiographic findings correlate with the scintigraphic probability for the diagnosis of pulmonary embolism (PE). Methods: From a total of 160 consecutive patients who underwent both nuclear imaging and invasive selective pulmonary angiography we reviewed the ventilation (Xe-133 in 2 oblique posterior views) and perfusion (Tc-MAA) (VQ) scans and selective angiograms of those 40 patients (15 men; 25 women, average age 57) who were discharged from hospital on anticoagulants with a diagnosis of PE. Results: the VQ scans were read as high (N=18; 45%), intermediate (N=10; 25%) or low (N=12; 30%) probability. The angiograms were interpreted as either positive (filling defect, trailing embolus or branch occlusion) (N=29; 73%), single tiny embolus (single small sub-segmental filling defect) (N=5; 12%), or equivocal (N=6; 15%). The distribution of the angiographic sub-groups among the 3 scintigraphic categories is presented. Conclusion: In patients diagnosed with PE based on selective angiography, a lower probability of PE on VQ scintigraphy correlates with a lesser degree of diagnostic certainty on angiography. (author)

  7. Angiographic characteristics of premature coronary artery disease in pakistan population; a prospective cross-sectional study

    International Nuclear Information System (INIS)

    Objective: To study the angiographic characteristics of premature coronary artery disease in our population. Methodology: From April 2014 to March 2015, coronary angiograms of 102 patients less than 40 years of age with a definitive diagnosis of ischemic heart disease were studied. Traditional risk factors of atherosclerosis were documented. Mode of presentation and symptoms were recorded along with angiographic findings of coronary artery disease severity, degree of coronary involvement, culprit vessel, lesion morphology, coronary dominance, coronary ectasia and left ventricular systolic function. Results: Mean age was 36.4 ± 4.1 years and 91% were male. Overall, left ventricular systolic function were fairly preserved (82%). 52% patients had single vessel CAD, 25% had double vessel while 19% had triple vessel coronary artery disease. Four patients had no luminal stenosis on coronary angiogram. LAD was the culprit vessel in 58.8%, RCA in 24.5% and left circumflex artery in 16.7% cases. More than 82% culprit lesions were severe or critical. 58% lesions were morphologically complex B2/C type while only 42% lesions were type A/B1. Coronary ectasia was seen in nearly 25% cases and all had ACS presentation. Right dominance was more common than left (57.8% vs 37.3%) while only 4.9% cases had dual posterior septal supply. Conclusion: Premature CAD in our population is acutely symptomatic, severe, complex (B2/C), single vessel disease. (author)

  8. Angiographic manifestation and transcatheter arterial embolization of proper esophageal artery in hemoptysis

    International Nuclear Information System (INIS)

    Objective: To investigate the angiographic manifestation of the proper esophageal artery (PEA), the high risk factors for the presence of the anomalous PEA in hemoptysis and to evaluate the safety of transcatheter arterial embolization (TAE) of the PEA using gelatin sponge (GS). Methods: Selective esophageal arteriography was performed in forty-three patients with hemoptysis, including 15 cases of pulmonary tuberculosis, 18 cases of bronchiectasis, 7 cases of posttuberculous bronchiectasis and three cases of lung cancer. One case experienced failure of bronchial arterial embolization. The angiographic manifestation of the PEAs was studied. The complications of the procedure and clinical results were observed in the patients who underwent TAE using GS. Results: Thirty-nine PEAs were catheterized selectively in 37 patients (86.0%). Eighteen anomalous PEAs (46.2%) were catheterized selectively in 17 patients (45.9%). The anomalous PEAs showed tortuosity, dilatation, hyperplasia, shunting with pulmonary artery and anastomosis with the bronchial artery. All lesions involved basal segment of inferior pulmonary lobar. Bronchiectasis was the most frequent disease for PEA abnormality. No complications occurred and satisfactory curative effect was achieved with TAE of the anomalous PEAs. Conclusions: It is necessary to perform selective proper esophageal arteriography when the lesion involves basal segment of inferior pulmonary lobar in hemoptysis. Supplemental TAE of the anomalous PEA using GS is safe and valuable in the management of hemoptysis. (authors)

  9. Gadolinium-enhanced MR angiography of the breast: Is breast cancer associated with ipsilateral higher vascularity?

    International Nuclear Information System (INIS)

    The aim of this study was to assess a possible association between breast malignancy and ipsilateral higher vascularity on gadolinium-enhanced MR angiography. One hundred six patients were examined by dynamic gadolinium-enhanced 3D MR imaging. Magnetic resonance angiographic views were generated by image subtraction and maximum intensity projection. The study included 85 patients with unilateral malignant breast neoplasms and 21 with unilateral benign lesions. Three blinded readers independently reviewed the MR angiograms after masking the lesions and the corresponding contralateral sites. The readers were asked to determine whether vascularity was higher on the right side, higher on the left side, or equal on both sides. The results were analyzed by the Kappa statistic and Pearson's chi-square test. The blood vessels of the breasts were clearly seen in all cases. There was good agreement among the observers (kappa > 0.54) in assessing vascularity on both sides. Breasts harboring malignant neoplasms were found to have a higher vascularity than the contralateral breasts (p < 0.005). This sign of malignancy had a sensitivity of 76.5 %, a specificity of 57 %, and an accuracy of 72.6 %. Blood vessels of the breast can be depicted by MR angiography. Unilateral malignant neoplasms are associated with a higher ipsilateral vascularity. In conjunction with other indications of malignancy on gadolinium-enhanced MR images, a higher ipsilateral vascularity may serve as an additional sign of malignancy. (orig.)

  10. Imaging Pediatric Vascular Lesions

    Science.gov (United States)

    Nguyen, Tuyet A.; Krakowski, Andrew C.; Naheedy, John H.; Kruk, Peter G.

    2015-01-01

    Vascular anomalies are commonly encountered in pediatric and dermatology practices. Most of these lesions are benign and easy to diagnose based on history and clinical exam alone. However, in some cases the diagnosis may not be clear. This may be of particular concern given that vascular anomalies may occasionally be associated with an underlying syndrome, congenital disease, or serious, life-threatening condition. Defining the type of vascular lesion early and correctly is particularly important to determine the optimal approach to management and treatment of each patient. The care of pediatric patients often requires collaboration from a multitude of specialties including pediatrics, dermatology, plastic surgery, radiology, ophthalmology, and neurology. Although early characterization of vascular lesions is important, consensus guidelines regarding the evaluation and imaging of vascular anomalies does not exist to date. Here, the authors provide an overview of pediatric vascular lesions, current classification systems for characterizing these lesions, the various imaging modalities available, and recommendations for appropriate imaging evaluation. PMID:26705446

  11. Imaging Pediatric Vascular Lesions.

    Science.gov (United States)

    Nguyen, Tuyet A; Krakowski, Andrew C; Naheedy, John H; Kruk, Peter G; Friedlander, Sheila Fallon

    2015-12-01

    Vascular anomalies are commonly encountered in pediatric and dermatology practices. Most of these lesions are benign and easy to diagnose based on history and clinical exam alone. However, in some cases the diagnosis may not be clear. This may be of particular concern given that vascular anomalies may occasionally be associated with an underlying syndrome, congenital disease, or serious, life-threatening condition. Defining the type of vascular lesion early and correctly is particularly important to determine the optimal approach to management and treatment of each patient. The care of pediatric patients often requires collaboration from a multitude of specialties including pediatrics, dermatology, plastic surgery, radiology, ophthalmology, and neurology. Although early characterization of vascular lesions is important, consensus guidelines regarding the evaluation and imaging of vascular anomalies does not exist to date. Here, the authors provide an overview of pediatric vascular lesions, current classification systems for characterizing these lesions, the various imaging modalities available, and recommendations for appropriate imaging evaluation. PMID:26705446

  12. Externally Occulted Terrestrial Planet Finder Coronagraph: Simulations and Sensitivities

    CERN Document Server

    Lyon, Richard G; Lo, Amy; Cash, Webster; Starkman, Glenn D; Vanderbei, Robert J; Kasdin, N Jeremy; Copi, Craig J

    2007-01-01

    A multitude of coronagraphic techniques for the space-based direct detection and characterization of exo-solar terrestrial planets are actively being pursued by the astronomical community. Typical coronagraphs have internal shaped focal plane and/or pupil plane occulting masks which block and/or diffract starlight thereby increasing the planet's contrast with respect to its parent star. Past studies have shown that any internal technique is limited by the ability to sense and control amplitude, phase (wavefront) and polarization to exquisite levels - necessitating stressing optical requirements. An alternative and promising technique is to place a starshade, i.e. external occulter, at some distance in front of the telescope. This starshade suppresses most of the starlight before entering the telescope - relaxing optical requirements to that of a more conventional telescope. While an old technique it has been recently been advanced by the recognition that circularly symmetric graded apodizers can be well appro...

  13. An overview of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Zeinab Nabil Ahmed Said

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our nderstanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.

  14. New insights to occult gastrointestinal bleeding: From pathophysiology to therapeutics

    Institute of Scientific and Technical Information of China (English)

    Antonio; Damián; Sánchez-Capilla; Paloma; De; La; Torre-Rubio; Eduardo; Redondo-Cerezo

    2014-01-01

    Obscure gastrointestinal bleeding is still a clinical challenge for gastroenterologists. The recent development of novel technologies for the diagnosis and treatment of different bleeding causes has allowed a better management of patients, but it also determines the need of a deeper comprehension of pathophysiology and the analysis of local expertise in order to develop a rational management algorithm. Obscure gastrointestinal bleeding can be divided in occult, when a positive occult blood fecal test is the main manifestation, and overt, when external sings of bleeding are visible. In this paper we are going to focus on overt gastrointestinal bleeding, describing the physiopathology of the most usual causes, analyzing the diagnostic procedures available, from the most classical to the novel ones, and establishing a standard algorithm which can be adapted depending on the local expertise or availability. Finally, we will review the main therapeutic options for this complex and not so uncommon clinical problem.

  15. Angiographic evaluation

    International Nuclear Information System (INIS)

    Failure of a transplanted kidney may be caused by any of several factors requiring different methods of management. It is thus necessary to distinguish between rejection, acute tubular necrosis, obstruction of the main blood vessels in the graft, and obstruction of the ureter. Careful evaluation is particularly important when cadaver kidneys are used, for which the functional 2-year survival rate is only 40-50%, compared with 70-80% for living related donor kidneys. Formerly renal transplant angiography was often performed to differentiate between acute rejection and acute ischemic tubular necrosis as the cause of graft dysfunction in the immediate postoperative period. Now, however, angiography for the patient with a failing graft is restricted mainly to the search for renal artery stenosis and arterial or renal vein thrombosis. Although the study may be specific when a full-blown pattern of rejection is present, routine angiography has proved to be of little value when rejection is suspected

  16. Vascularity in thyroid neoplasms

    DEFF Research Database (Denmark)

    Larsen, Karen Kjaer; Andersen, Niels Frost; Melsen, Flemming;

    2006-01-01

    The aim of the present study was to evaluate the reliability of four different methods (vascular grading, Chalkley count, microvessel density (MVD) and stereological estimation) for quantifying intratumoral microvascularity in thyroid neoplasms, by comparing the variability within and between...... count should be the preferred method for assessing microvascularity in thyroid neoplasms. The diagnostic evaluation revealed a tendency towards higher degree of vascularity in FA compared to both FC and PC for all methods. No statistically significant association was seen between vascular density and...

  17. All-Sky Earth Occultation Observations with the Fermi Gamma Ray Burst Monitor

    CERN Document Server

    Wilson-Hodge, Colleen A; Bhat, P N; Briggs, M S; Chaplin, V; Connaughton, V; Camero-Arranz, A; Case, G; Cherry, M; Rodi, J; Finger, M H; Jenke, P; Haynes, R H

    2009-01-01

    Using the Gamma Ray Burst Monitor (GBM) on-board Fermi, we are monitoring the hard X-ray/soft gamma ray sky using the Earth occultation technique. Each time a source in our catalog enters or exits occultation by the Earth, we measure its flux using the change in count rates due to the occultation. Currently we are using CTIME data with 8 energy channels spanning 8 keV to 1 MeV for the GBM NaI detectors and spanning 150 keV to 40 MeV for the GBM BGO detectors. Our preliminary catalog consists of galactic X-ray binaries, the Crab Nebula, and active galactic nuclei. In addition, to Earth occultations, we have observed numerous occultations with Fermi's solar panels. We will present early results. Regularly updated results can be found on our website http://gammaray.nsstc.nasa.gov/gbm/science/occultation

  18. [Occult pneumothorax: Does it take drain before elective surgery?].

    Science.gov (United States)

    Bensghir, M; Moutaoukil, M; Meziane, M; Jaafari, A; Hemmaoui, B; Haimeur, C

    2016-08-01

    Pneumothorax occult is defined by the presence of a non-visible to standard asymptomatic pneumothorax and pulmonary diagnosed only by X-ray computed tomography. The presence of this type of pneumothorax before planned surgery is a rare situation. What to do remains non-consensual. Through two clinic cases and a literature review, the authors discuss the modalities of management of this entity. PMID:27113614

  19. Assimilation of GNSS radio occultation observations in GRAPES

    OpenAIRE

    Liu, Y; Xue, J.

    2014-01-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly ...

  20. Occult persistence and lymphotropism of hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Tram NQ Pham; Tomasz I Michalak

    2008-01-01

    Recent discovery of occult hepatitis C virus (HCV)infection persisting after spontaneous or antiviral therapy-induced resolution of hepatitis C was made possible by the introduction of nucleic acid amplification assays capable of detecting HCV RNA at sensitivities superseding those offered by clinical tests. Although individuals with this seemingly silent HCV infection are usually anti-HCV antibody reactive and have normal liver function tests, occult HCV infection has also been reported in anti-HCV-negative individuals with persistently elevated liver enzymes of unknown etiology. Studies have shown that HCV RNA can persist for years in serum, iymphomononuciear cells and liver in the absence of clinical symptoms, although histological evidence of a mild inflammatory liver injury can be occasionally encountered. Furthermore, while HCV RNA can be detected in circulating lymphoid cells in approximately 30% of cases, a short-term culture under stimulatory conditions augments HCV replication in these cells allowing detection of virus in otherwise HCV-negative cases. HCV infects different immune cell subsets, including CD4+ and CD8+ T lymphocytes, B cells and monocytes. Studies employing cional sequencing and single-stranded conformational polymorphism analyses have revealed unique HCV variants residing in immune cells, further strengthening the notion of HCV lymphotropism. Overall, the data accumulated suggest that occult HCV infection is a common consequence of resolution of symptomatic hepatitis C and that examination of the cells of the immune system is an effective approach to diagnosis of HCV infection and its long-term persistence. Further work is required to fully realize pathogenic and epidemiological consequences of occult HCV persistence.

  1. Occult pneumothorax in the mechanically ventilated trauma patient

    OpenAIRE

    Ball, Chad G.; Hameed, S. Morad; Evans, Dave; Kortbeek, John B.; Kirkpatrick, Andrew W

    2003-01-01

    The term occult pneumothorax (OP) describes a pneumothorax that is not suspected on the basis of clinical examination or plain radiography but is ultimately detected with thoracoabdominal computed tomography (CT). This situation is increasingly common in trauma care with the increased use of CT. The rate is approximately 5% in injured people presenting to hospital, with CT revealing at least twice as many pneumothoraces as suspected on plain radiography. Whereas pneumothorax is a common and t...

  2. The Structure of Titan's Atmosphere from Cassini Radio Occultations

    Science.gov (United States)

    Schinder, Paul J.; Flasar, F. Michael; Marouf, Essam A.; French, Richard G.; McGhee, Colleen A.; Kliore, Arvydas J.; Rappaport, Nicole J.; Barbinis, Elias; Fleischman, Don; Anabtawi, Aseel

    2011-01-01

    We present results from the two radio occultations of the Cassini spacecraft by Titan in 2006, which probed mid-southern latitudes. Three of the ingress and egress soundings occurred within a narrow latitude range, 31.34 deg S near the surface, and the fourth at 52.8 deg S. Temperature - altitude profiles for all four occultation soundings are presented, and compared with the results of the Voyager 1 radio occultation (Lindal et al., 1983), the HASI instrument on the Huygens descent probe (Fulchignoni et al., 2005), and Cassini CIRS results (Flasar et al., 2005; Achterberg et al., 2008b). Sources of error in the retrieved temperature - altitude profiles are also discussed, and a major contribution is from spacecraft velocity errors in the reconstructed ephemeris. These can be reduced by using CIRS data at 300 km to make along-track adjustments of the spacecraft timing. The occultation soundings indicate that the temperatures just above the surface at 31-34 deg S are about 93 K, while that at 53 deg S is about 1 K colder. At the tropopause, the temperatures at the lower latitudes are all about 70 K, while the 53 deg S profile is again 1 K colder. The temperature lapse rate in the lowest 2 km for the two ingress (dawn) profiles at 31 and 33 deg S lie along a dry adiabat except within approximately 200m of the surface, where a small stable inversion occurs. This could be explained by turbulent mixing with low viscosity near the surface. The egress profile near 34 deg S shows a more complex structure in the lowest 2 km, while the egress profile at 53 deg S is more stable.

  3. Analyses for a Modernized GNSS Radio Occultation Receiver

    Science.gov (United States)

    Griggs, Erin R.

    Global Navigation Satellite System (GNSS) radio occultation (RO) is a remote sensing technique that exploits existing navigation signals to make global, real-time observations of the Earth's atmosphere. A specialized RO receiver makes measurements of signals originating from a transmitter onboard a GNSS spacecraft near the Earth's horizon. The radio wave is altered during passage through the Earth's atmosphere. The changes in the received signals are translated to the refractivity characteristics of the intervening medium, which enable the calculation of atmospheric pressure, temperature, and humidity. Current satellite missions employing GNSS RO have provided invaluable and timely information for weather and climate applications. Existing constellations of occultation satellites, however, are aging and producing fewer quality measurements. Replacement fleets of RO satellites are imperative to sustain and improve the global coverage and operational impact achieved by the current generation of RO satellites. This dissertation describes studies that facilitate the development of next generation RO receivers and satellite constellations. Multiple research efforts were conducted that aim to improve the quantity and quality of measurements made by a future satellite-based RO collection system. These studies range in magnitude and impact, and begin with a receiver development study using ground-based occultation data. Future RO constellations and collection opportunities were simulated and autonomous occultation prediction and scheduling capabilities were implemented. Finally, a comprehensive study was conducted to characterize the stability of the GNSS atomic frequency standards. Oscillator stability for a subset of satellites in the GNSS was found to be of insufficient quality at timescales relevant to RO collections and would degrade the atmospheric profiling capabilities of an RO system utilizing these signals. Recommendations for a high-rate clock correction network

  4. Occult Dirofilariosis in Dogs of North Eastern Region in India

    OpenAIRE

    Sonjoy Kumar-Borthakur; Dilip Kumar-Deka; Saidul Islam; Prabhat Chandra-Sarmah

    2015-01-01

    Background: The North Eastern Region in India is endemic for canine heartworm disease but in clinics accurate diagnosis is some times difficult. The aim of the present study was to determine the prevalence of occult infections for heartworm disease in canine in two geographical regions of North Eastern India.Methods: A total of 782 numbers of three categories of dogs namely, working dogs of military and paramilitary forces, pet dogs and stray dogs were screened for the presence of heartworm i...

  5. Buoyancy waves in Pluto's high atmosphere: Implications for stellar occultations

    CERN Document Server

    Hubbard, W B; Kulesa, C A; Benecchi, S D; Person, M J; Elliot, J L; Gulbis, A A S

    2009-01-01

    We apply scintillation theory to stellar signal fluctuations in the high-resolution, high signal/noise, dual-wavelength data from the MMT observation of the 2007 March 18 occultation of P445.3 by Pluto. A well-defined high wavenumber cutoff in the fluctuations is consistent with viscous-thermal dissipation of buoyancy waves (internal gravity waves) in Pluto's high atmosphere, and provides strong evidence that the underlying density fluctuations are governed by the gravity-wave dispersion relation.

  6. Lunar occultation observation of μ Sgr: A progress report

    International Nuclear Information System (INIS)

    Lunar Occultation (LO) is an event where limb of the Moon passing over a particular heavenly bodies such as stars, asteroids, or planets. In other words, during the event, stars, asteroids and planets are occulted by the Moon. When occulted objects contact the lunar limb, there will be a diffraction fringe(s) which can be measured photometrically, until the signal vanishes into noise. This event will give us a valuable information about binarities (of stars) and/or angular diameters estimation (of stars, planets, asteroids) in milliarcsecond resolution, by fitting with theoretical LO pattern. CCDs are common for LO observation because of its fast read out, and recently are developed for sub-meter class telescope. In this paper, our LO observation attempt of μ Sgr and its progress report are presented. The observation was conducted on July 30th, 2012 at Bosscha Observatory, Indonesia, using 45cm f/12 GOTO telescope combined with ST-9 XE CCD camera and Bessel B filter. We used drift-scan method to obtain light curve of the star as it was disappearing behind Moon's dark limb. Our goal is to detect binarity (or multiplicity) of this particular object

  7. Renal trauma in occult ureteropelvic junction obstruction: CT findings

    International Nuclear Information System (INIS)

    The aim of this study was to present CT findings of occult ureteropelvic junction obstruction in patients with renal trauma and to describe the clinical signs and singular CT features that are characteristically observed with trauma and are relevant to management of these patients. We retrospectively reviewed 82 helical CT studies in patients with renal trauma referred to our institution. We found 13 cases of occult preexisting renal pathology, six of which were occult ureteropelvic junction obstructions. The clinical presentation, radiologic findings of trauma according to the Federle classification, and CT findings of obstructed ureteropelvic junction are presented. We found three category-I lesions (one in a horseshoe kidney), two of them treated with nephrostomy because of increased ureteropelvic junction obstruction due to pelvic clots; two category-II lesions (parenchymal and renal pelvis lacerations) that had presented only with microhematuria; and one category-IV lesion (pelvic laceration alone). Pelvic extension was demonstrated in all the cases with perirenal collections. The CT studies in all the cases with suspected ureteropelvic junction obstruction showed decreased parenchymal thickness and enhancement, and dilatation of the renal pelvis and calyx, with a normal ureter. Computed tomography can provide information to confidently diagnose underlying ureteropelvic junction obstruction in renal trauma, categorize the traumatic injury (at times clinically silent) and facilitate proper management according to the singularities observed, such us rupture of the renal pelvis alone (Federle category IV) and increasing ureteropelvic obstruction due to clots which can be decompressed by nephrostomy. (orig.)

  8. Pathogenesis of occult chronic hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Rocio Aller de la Fuente; María L Gutiérrez; Javier Garcia-Samaniego; Conrado Fernández-Rodriguez; Jose Luis Lledó; Gregorio Castellano

    2011-01-01

    Occult hepatitis B infection (OBI) is characterized by hepatitis B virus (HBV) DNA in serum in the absence of hepatitis B surface antigen (HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns. Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays; but more frequently it is due to a strong suppression of viral replication and gene expression. OBI is an entity with world-wide diffusion. The failure to detect HBsAg, despite the persistence of the viral DNA, is due in most cases to the strong suppression of viral replication and gene expression that characterizes this "occult" HBV infection; although the mechanisms responsible for suppression of HBV are not well understood. The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection. Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.

  9. Occult hepatitis C virus infection: A new form of hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Vicente Carre(n)o

    2006-01-01

    Occult hepatitis C virus (HCV) infection is a new recently characterized entity. This occult infection can be present in two different clinical situations: in anti-HCV negative,serum HCV-RNA negative patients with abnormal liver function tests and in anti-HCV positive subjects with normal values of liver enzymes and without serum HCV-RNA. This review describes recent studies of occult HCV infection in both kinds of patients.(c) 2006 The WJG Press. All rights reserved.

  10. Using the EXIST Active Shields for Earth Occultation Observations of X-ray Sources

    OpenAIRE

    Wilson, Colleen. A.; Fishman, G. J.; Hong, J. -S.; Grindlay, J.E.; H. Krawczynski(Department of Physics, Washington University, St. Louis, MO 63130, USA)

    2005-01-01

    The EXIST active shields, planned for the main detectors of the coded aperture telescope, will have approximately 15 times the area of the BATSE detectors, and they will have a good geometry on the spacecraft for viewing both the leading and trailing Earth's limb for occultation observations. These occultation observations will complement the imaging observations of EXIST and can extend them to higher energies. Earth occultation observations of the hard X-ray sky with BATSE on the Compton Gam...

  11. Micro-angiography for neuro-vascular imaging. I. Experimental evaluation and feasibility

    International Nuclear Information System (INIS)

    Minimally invasive image-guided neuro-vascular interventions require very high image-resolution and quality, specifically over regions-of-interest (ROI) crucial to the procedure. ROI imaging or micro-angiography, allows limited patient integral radiation dose while permitting rapid frame transfer of high-resolution images. The design and performance of a charge coupled device (CCD) based x-ray detector or micro-angiographic camera was assessed for neuro-vascular procedures. The detector consists of a 250-μm-thick CsI(Tl) phosphor fiber-optically coupled through a 1.8:1 taper to a CCD chip, with an effective image pixel size of 50 μm and a frame rate of 5 fps in the 2:1 pixel-binned mode. The characteristics of the camera including the modulation transfer function (MTF), the noise equivalent quanta, the detective quantum efficiency, observer studies, and the effect of geometric magnification were evaluated. The MTF was found to have nonzero (1.7%) value at the Nyquist frequency of 10 cycles/mm, while the DQE(0) had a value of ∼55%. All values were measured using head equivalent attenuating material in the beam at 80 kVp. Human observer studies performed using the 2 Alternative Forced Choice method revealed that iodinated vessels with inner diameter of 100 μm and 2 cm in length can be seen with a confidence level greater than 75%. The observer studies included a comparison with ideal observer performance calculations based on the integral signal to noise ratio in the image. Probabilities of visualization of various objects of interest in a neuro-intervention, such as stents, were assessed. A geometric magnification of 1 was found to be best for imaging under neuro-angiographic conditions. The detector appeared to satisfy all the demands of neuro-angiography and showed promise as an improvement over existing angiographic detectors

  12. Magnitudes of selected stellar occultation candidates for Pluto and other planets, with new predictions for Mars and Jupiter

    Science.gov (United States)

    Sybert, C. B.; Bosh, A. S.; Sauter, L. M.; Elliot, J. L.; Wasserman, L. H.

    1992-01-01

    Occultation predictions for the planets Mars and Jupiter are presented along with BVRI magnitudes of 45 occultation candidates for Mars, Jupiter, Saturn, Uranus, and Pluto. Observers can use these magnitudes to plan observations of occultation events. The optical depth of the Jovian ring can be probed by a nearly central occultation on 1992 July 8. Mars occults an unusually red star in early 1993, and the occultations for Pluto involving the brightest candidates would possibly occur in the spring of 1992 and the fall of 1993.

  13. The 1998 November 14 Occultation of GSC 0622-00345 by Saturn. I. Techniques for Ground-Based Stellar Occultations

    CERN Document Server

    Harrington, Joseph; 10.1088/0004-637X/716/1/398

    2010-01-01

    On 1998 November 14, Saturn and its rings occulted the star GSC 0622-00345. We observed atmospheric immersion with NSFCAM at the National Aeronautics and Space Administration's Infrared Telescope Facility on Mauna Kea, Hawaii. Immersion occurred at 55.5\\circ S planetocentric latitude. A 2.3 {\\mu}m, methane-band filter suppressed reflected sunlight. Atmospheric emersion and ring data were not successfully obtained. We describe our observation, light-curve production, and timing techniques, including improvements in aperture positioning, removal of telluric scintillation effects, and timing. Many of these techniques are known within the occultation community, but have not been described in the reviewed literature. We present a light curve whose signal-to-noise ratio per scale height is 267, among the best ground-based signals yet achieved, despite a disadvantage of up to 8 mag in the stellar flux compared to prior work.

  14. THE 1998 NOVEMBER 14 OCCULTATION OF GSC 0622-00345 BY SATURN. I. TECHNIQUES FOR GROUND-BASED STELLAR OCCULTATIONS

    International Nuclear Information System (INIS)

    On 1998 November 14, Saturn and its rings occulted the star GSC 0622-00345. We observed atmospheric immersion with NSFCAM at the National Aeronautics and Space Administration's Infrared Telescope Facility on Mauna Kea, Hawaii. Immersion occurred at 55.05 S planetocentric latitude. A 2.3 μm, CH4-band filter suppressed reflected sunlight. Atmospheric emersion and ring data were not successfully obtained. We describe our observation, light curve production, and timing techniques, including improvements in aperture positioning, removal of telluric scintillation effects, and timing. Many of these techniques are known within the occultation community, but have not been described in the reviewed literature. We present a light curve whose signal-to-noise ratio per scale height is 267, among the best ground-based signals yet achieved, despite a disadvantage of up to 8 mag in the stellar flux compared to prior work.

  15. Injuries as a result of sports and vacation activities: Fractures with concomitant vascular injuries. Diagnosis and treatment concept

    International Nuclear Information System (INIS)

    Extremity fractures with concomitant vascular injuries are surgical emergencies. Especially injuries of the upper extremities require a preoperative angiographic examination for the localization of the vascular lesion. In vascular lesions of the lower extremities a primary angiography is not necessary, if there is an opportunity for an intraoperative radiologic evaluation. In our traumatological department 104 patients were treated over the last 15 years with that combined injury. The concept of immediate stabilization of the fracture with simultaneous or postponed arterial repair has been proved to be appropriate. The fasziotomy as prophylactic procedure of a postischemic compartment syndrome is also a part of our concept during the last years. The late results in our mostly young patients depended on the degree of soft tissue damage and the time of ischemia. The often untreatable nerve lesions contributed to a loss of use of about 30% in the late courses. (orig.)

  16. Poikiloderma vasculare atrophicans

    Directory of Open Access Journals (Sweden)

    Padmavathy L

    1994-01-01

    Full Text Available A 65 year old lady presented with generalised pruritus and discolouration of skin and mucous membranes of 5 years duration. The histopathology from the cutaneous lesions revealed features suggestive of poikiloderma vasculare atrophicans (PVA. Investigations did not reveal any underlying connective tissue disease,lymphoma or systemic disease. A diagnosis of idiopathic poikiloderma vasculare atrophicans was made.

  17. Poikiloderma vasculare atrophicans

    OpenAIRE

    Padmavathy L; Prasad PVS; Prasanna K; Rao L

    1994-01-01

    A 65 year old lady presented with generalised pruritus and discolouration of skin and mucous membranes of 5 years duration. The histopathology from the cutaneous lesions revealed features suggestive of poikiloderma vasculare atrophicans (PVA). Investigations did not reveal any underlying connective tissue disease,lymphoma or systemic disease. A diagnosis of idiopathic poikiloderma vasculare atrophicans was made.

  18. Stenting for symptomatic vertebral artery stenosis associated with bilateral carotid rate mirabile: The long-term clinical and angiographic outcome

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Jang Hyun; Kim, Byung Moon [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2015-06-15

    Symptomatic vertebral artery (VA) stenosis associated with bilateral carotid rate mirabile (CRM) has not been reported. We report the long-term clinical and angiographic outcome after stenting for symptomatic VA stenosis in the patient with bilateral CRM. This report is the first case that symptomatic VA stenosis associated with bilateral CRM was treated with stenting.

  19. Usefulness of angiographic embolization endoscopic metallic clip placement in patient with non-variceal upper gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Min Jae; Hwang, Cheol Mog; Kim, Ho Jun; Cho, Young Jun; Bae, Seok Hwan [Dept. of Radiology, Konyang University Hospital, Daejeon (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young [Dept. of Radiology, Chungnam National University College of Medicine, Daejeon (Korea, Republic of); Kang, Chae Hoon [Dept. of Radiology, Inje University College of Medicine, Pusan Paik Hospital, Busan (Korea, Republic of)

    2013-08-15

    The aim of this study is to assess the usefulness of angiographic embolization after endoscopic metallic clip placement around the edge of non-variceal upper gastrointestinal bleeding ulcers. We have chosen 41 patients (mean age, 65.2 years) with acute bleeding ulcers (22 gastric ulcers, 16 duodenal ulcers, 3 malignant ulcers) between January 2010 and December 2012. We inserted metallic clips during the routine endoscopic treatments of the bleeding ulcers. Subsequent transcatheter arterial embolization was performed within 2 hours. We analyzed the angiographic positive rates, angiographic success rates and clinical success rates. Among the 41 patients during the angiography, 19 patients (46%) demonstrated active bleeding points. Both groups underwent embolization using microcoils, N-butyl-cyano-acrylate (NBCA), microcoils with NBCA or gelfoam particle. There are no statistically significant differences between these two groups according to which embolic materials are being used. The bleeding was initially stopped in all patients, except the two who experienced technical failures. Seven patients experienced repeated episodes of bleeding within two weeks. Among them, 4 patients were successful re-embolized. Another 3 patients underwent gastrectomy. Overall, clinical success was achieved in 36 of 41 (87.8%) patients. The endoscopic metallic clip placement was helpful to locate the correct target vessels for the angiographic embolization. In conclusion, this technique reduced re-bleeding rates, especially in patients who do not show active bleeding points.

  20. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt; Bak, M; Vach, W; Rose, C

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... had clinical impact for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  1. [Vascular factors in glaucoma].

    Science.gov (United States)

    Mottet, B; Aptel, F; Geiser, M; Romanet, J P; Chiquet, C

    2015-12-01

    The exact pathophysiology of glaucoma is not fully understood. Understanding of the vascular pathophysiology of glaucoma requires: knowing the techniques for measuring ocular blood flow and characterizing the topography of vascular disease and the mechanisms involved in this neuropathy. A decreased mean ocular perfusion pressure and a loss of vascular autoregulation are implicated in glaucomatous disease. Early decrease in ocular blood flow has been identified in primary open-angle glaucoma and normal pressure glaucoma, contributing to the progression of optic neuropathy. The vascular damage associated with glaucoma is present in various vascular territories within the eye (from the ophthalmic artery to the retina) and is characterized by a decrease in basal blood flow associated with a dysfunction of vasoregulation. PMID:26597554

  2. Development of an occult metric for common motor vehicle crash injuries - biomed 2013.

    Science.gov (United States)

    Schoell, Samantha L; Weaver, Ashley A; Stitzel, Joel D

    2013-01-01

    Detection of occult injuries, which are not easily recognized and are life-threatening, in motor vehicle crashes (MVCs) is crucial in order to reduce fatalities. An Occult Injury Database (OID) was previously developed by the Center for Transportation Injury Research (CenTIR) using the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) 1997-2001 which identified occult and non-occult head, thorax, and abdomen injuries. The objective of the current work was to develop an occult injury model based on underlying injury characteristics to derive an Occult Score for common MVC-induced injuries. A multiple logistic regression model was developed utilizing six injury parameters to generate a probability formula which assigned an Occult Score for each injury. The model was applied to a list of 240 injuries comprising the top 95 percent of injuries occurring in NASS-CDS 2000-2011. The parameters in the model included a continuous Cause MRR/year variable indicating the annual proportion of occupants sustaining a given injury whose cause of death was attributed to that injury. The categorical variables in the model were AIS 2-3 vs. 4-6, laceration, hemorrhage/hematoma, contusion, and intracranial. Results indicated that injuries with a low Cause MRR/year and AIS severity of 4-6 had an increased likelihood of being occult. In addition, the presence of a laceration, hemorrhage/hematoma, contusion, or intracranial injury also increased the likelihood of an injury being occult. The Occult Score ranges from zero to one with a threshold of 0.5 as the discriminator of an occult injury. Of the considered injuries, it was determined that 54% of head, 26% of thorax, and 23% of abdominal injuries were occult injuries. No occult injuries were identified in the face, spine, upper extremity, or lower extremity body regions. The Occult Score generated can be useful in advanced automatic crash notification research and for the detection of serious occult injuries in

  3. Protocols for quality assurance for radiographers and nurses in the angiographic room

    International Nuclear Information System (INIS)

    Full text: Protocols for quality assurance are essential in the angiographic room activities for radiographers and nurses Methodology contains gathering information, defining goals, defining patients group, analysis of risk, precising the examination, theoretical data review. Protocols are presented for approval to experts and administrative authorities. Combinations of radiographic activities and surgical methods are characteristics for invasive methods. Team work between nurses and radiographers makes the most important differences among the range of radiographers' duties. Requirement of Bulgarian regulations as medical standard for diagnostic imaging and public health laws required peer reviewing of the protocol. Patient written consent is important part of the protocol for these risky procedures, as well in answering to increase of patient organization requirement and information level of patients

  4. Angiographic and CT findings after intra-arterial cytostasis of colorectal liver metastases

    International Nuclear Information System (INIS)

    Between October 1983 and January 1986, sexteen patients with inoperable liver metastases from colorectal carcinomas were treated by single or cyclical intraarterial chemotherapy introduced either through an angiographic catheter or by means of a subcutaneously implanted access point (Port-A-Cath). Before each treatment cycle, the position of the catheter and the state of the vessels was examined by subtraction angiography in order to avoid complications and to confirm that the cytostatic agents were actually perfusing metastases, as shown by angio-CT. The complementary nature of the information obtained by these methods and their superiority over scintigraphy with 99mTc macroaggregated albumin particles is documented and the most frequent complications of regional tumour therapy are described. (orig.)

  5. Influencing factors of immediate angiographic results in intracranial aneurysms patients after endovascular treatment.

    Science.gov (United States)

    Chen, Jia-Xiang; Lai, Ling-Feng; Zheng, Kuang; Li, Guo-Xiong; He, Xu-Ying; Li, Liang-Ping; Duan, Chuan-Zhi

    2015-09-01

    The purpose of this study was to analyze influencing factors associated with immediate angiographic results in intracranial aneurysms patients after endovascular treatment (EVT), providing theoretical evidence and guidance for clinical treatment of intracranial aneurysms. Totally 529 patients met the inclusive criteria, consisting of 338 males and 191 females. Gender; age; history of hypertension, diabetes, and smoking; intracranial atherosclerosis; rupture status, size and location, features of aneurysmal neck, shapes; vasospasm; treatment modality; and degree of aneurysm occlusion were all carefully and completely recorded. All data were investigated in univariate and multivariate logistic regression model to determine whether they were correlated with the degree of aneurysm occlusion. According to aneurysm size, aneurysms were classified as micro-miniature, miniature, and large aneurysms. There were 451 narrow-neck aneurysms and 78 wide-neck aneurysms. Totally 417 were regular and 112 were irregular. And 125 were un-ruptured aneurysms; 404 were ruptured aneurysms. The modalities of treatment were as follows: embolization with coil (n = 415), stent-assisted coil embolization (n = 89), and balloon-assisted coil embolization (n = 25). Univariate analysis showed that aneurysm size, feature of aneurysm neck, shape, and rupture status might affect the immediate occlusion after EVT. Multivariate logistic regression analysis indicated that ruptured aneurysm, tiny aneurysm, and wide-neck aneurysm were independent influencing factors of complete occlusion of intracranial aneurysm. Aneurysm rupture status, size, feature of aneurysmal neck, and shape might be the independent influencing factors of immediate angiographic results in intracranial aneurysm patients after EVT. Un-ruptured, micro-miniature, narrow-neck, and regular-shaped aneurysms were more probable to be occluded completely. PMID:26100332

  6. Preliminary study of an angiographic and angio-tomographic technique based on K-edge filters

    International Nuclear Information System (INIS)

    Digital Subtraction Angiography is commonly affected by artifacts due to the patient movements during the acquisition of the images without and with the contrast medium. This paper presents a preliminary study on an angiographic and angio-tomographic technique based on the quasi-simultaneous acquisition of two images, obtained using two different filters at the exit of an X-ray tube. One of the two filters (K-edge filter) contains the same chemical element used as a contrast agent (gadolinium in this study). This filter absorbs more radiation with energy just above the so called K-edge energy of gadolinium than the radiation with energy just below it. The other filter (an aluminium filter in this study) is simply used to suppress the low-energy contribution to the spectrum. Using proper calibration curves, the two images are combined to obtain an image of the contrast agent distribution. In the angio-tomographic application of the proposed technique two images, corresponding to the two filter types, are acquired for each viewing angle of the tomographic scan. From the two tomographic reconstructions, it is possible to obtain a three-dimensional map of the contrast agent distribution. The technique was tested on a sample consisting of a rat skull placed inside a container filled with water. Six small cylinders with 4.7 mm internal diameter containing the contrast medium at different concentrations were placed inside the skull. In the plain angiographic application of the technique, five out of six cylinders were visible, with gadolinium concentration down to 0.96%. In the angio-tomographic application, all six cylinders were visible, with gadolinium concentration down to 0.49%. This preliminary study shows that the proposed technique can provide images of the contrast medium at low concentration without most of the artifacts that are present in images produced by conventional techniques. The results encourage further investigation on the feasibility of a clinical

  7. Preliminary study of an angiographic and angio-tomographic technique based on K-edge filters

    Energy Technology Data Exchange (ETDEWEB)

    Golosio, Bruno; Brunetti, Antonio [Dipartimento POLCOMING, Istituto di Matematica e Fisica, Università di Sassari, 07100 Sassari (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari (Italy); Oliva, Piernicola; Carpinelli, Massimo [Dipartimento di Chimica e Farmacia, Università di Sassari, 07100 Sassari (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari (Italy); Luca Masala, Giovanni [Dipartimento di Chimica e Farmacia, Università di Sassari, 07100 Sassari (Italy); Meloni, Francesco [Unità operativa di Diagnostica per immagini Asl n. 1, Ospedale Civile SS Annunziata, 07100 Sassari (Italy); Battista Meloni, Giovanni [Istituto di Scienze Radiologiche, Università di Sassari, 07100 Sassari (Italy)

    2013-08-14

    Digital Subtraction Angiography is commonly affected by artifacts due to the patient movements during the acquisition of the images without and with the contrast medium. This paper presents a preliminary study on an angiographic and angio-tomographic technique based on the quasi-simultaneous acquisition of two images, obtained using two different filters at the exit of an X-ray tube. One of the two filters (K-edge filter) contains the same chemical element used as a contrast agent (gadolinium in this study). This filter absorbs more radiation with energy just above the so called K-edge energy of gadolinium than the radiation with energy just below it. The other filter (an aluminium filter in this study) is simply used to suppress the low-energy contribution to the spectrum. Using proper calibration curves, the two images are combined to obtain an image of the contrast agent distribution. In the angio-tomographic application of the proposed technique two images, corresponding to the two filter types, are acquired for each viewing angle of the tomographic scan. From the two tomographic reconstructions, it is possible to obtain a three-dimensional map of the contrast agent distribution. The technique was tested on a sample consisting of a rat skull placed inside a container filled with water. Six small cylinders with 4.7 mm internal diameter containing the contrast medium at different concentrations were placed inside the skull. In the plain angiographic application of the technique, five out of six cylinders were visible, with gadolinium concentration down to 0.96%. In the angio-tomographic application, all six cylinders were visible, with gadolinium concentration down to 0.49%. This preliminary study shows that the proposed technique can provide images of the contrast medium at low concentration without most of the artifacts that are present in images produced by conventional techniques. The results encourage further investigation on the feasibility of a clinical

  8. A scoring system for the assessment of angiographic findings in non-occlusive mesenteric ischemia (NOMI)

    International Nuclear Information System (INIS)

    Purpose: To establish a standardized scoring system for angiographic findings in patients with non-occlusive mesenteric ischemia (NOMI). Materials and Methods: In 36 patients (mean age: 72 years), 53 angiographies of the superior mesenteric artery (SMA) were performed for suspected NOMI after cardiac or major aortic surgery. All examinations were performed using a standardized DSA technique. Two experienced radiologists performed a consensus reading blinded to the clinical information, on two occasions with an interval of two weeks. In order to investigate the reproducibility of the criteria, the images were assessed once by an intensivist and a medical student. Image analysis was performed with respect to vessel morphology, reflux of contrast medium into the aorta, small bowel parenchymal contrast enhancement and distension and the delay between arterial injection and portal vein filling. Results: Almost perfect intra-observer correlation was obtained for the assessment of the contrast medium reflux (κ = 0.82) and substantial correlation for the time of portal vein filling (κ = 0.66). Moderate correlations were obtained for the vessel morphology (κ = 0.51), small bowel enhancement (κ = 0.63) and distension (κ = 0.53). Contrast medium reflux into the aorta (κ = 0.77 and 0.63) and the time of portal vein filling (κ = 0.42 and 0.58) resulted in the highest inter-observer correlations between the radiologists and the intensivist as well as the radiologists and the student. Conclusion: In patients with suspected NOMI, using our scoring system yields high intra- and inter-observer correlations, allowing a standardized evaluation of angiographic findings. (orig.)

  9. A scoring system for the assessment of angiographic findings in non-occlusive mesenteric ischemia (NOMI)

    Energy Technology Data Exchange (ETDEWEB)

    Minko, P.; Stroeder, J.; Miodek, J.; Buecker, A.; Katoh, M. [Saarland Univ. Hospital, Homburg/Saar (Germany). Diagnostic and Interventional Radiology; Groesdonk, H.; Schaefers, H.J. [Saarland Univ. Hospital, Homburg/Saar (Germany). Dept. of Thoracic and Cardiovascular Surgery; Graeber, S. [Saarland Univ. Hospital, Homburg/Saar (Germany). Inst. of Medical Biometry, Epidemiology and Medical Informatics

    2012-09-15

    Purpose: To establish a standardized scoring system for angiographic findings in patients with non-occlusive mesenteric ischemia (NOMI). Materials and Methods: In 36 patients (mean age: 72 years), 53 angiographies of the superior mesenteric artery (SMA) were performed for suspected NOMI after cardiac or major aortic surgery. All examinations were performed using a standardized DSA technique. Two experienced radiologists performed a consensus reading blinded to the clinical information, on two occasions with an interval of two weeks. In order to investigate the reproducibility of the criteria, the images were assessed once by an intensivist and a medical student. Image analysis was performed with respect to vessel morphology, reflux of contrast medium into the aorta, small bowel parenchymal contrast enhancement and distension and the delay between arterial injection and portal vein filling. Results: Almost perfect intra-observer correlation was obtained for the assessment of the contrast medium reflux ({kappa} = 0.82) and substantial correlation for the time of portal vein filling ({kappa} = 0.66). Moderate correlations were obtained for the vessel morphology ({kappa} = 0.51), small bowel enhancement ({kappa} = 0.63) and distension ({kappa} = 0.53). Contrast medium reflux into the aorta ({kappa} = 0.77 and 0.63) and the time of portal vein filling ({kappa} = 0.42 and 0.58) resulted in the highest inter-observer correlations between the radiologists and the intensivist as well as the radiologists and the student. Conclusion: In patients with suspected NOMI, using our scoring system yields high intra- and inter-observer correlations, allowing a standardized evaluation of angiographic findings. (orig.)

  10. Cerebral Angiographic Findings of Cosmetic Facial Filler-related Ophthalmic and Retinal Artery Occlusion

    Science.gov (United States)

    2015-01-01

    Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions. PMID:26713062

  11. Ultrasonographic, computed tomographic and angiographic features of exophytically grown gastric smooth muscle tumors

    International Nuclear Information System (INIS)

    Ultrasonographic (US), computed tomographic (CT) and angiographic (AG) features of exophytic gastric smooth muscle tumors were analysed in two subjects. The first case was a 28-year-old female who had a tumor in the right upper quadrant. Imaging investigations indicated leiomyoma. She underwent operation, and the tumor found was a huge (11x10x8cm) gastric leiomyoma grown exophytically. The second case was a 68-year-old female whose chief complaints were anorexia and weightloss. An upper gastrointestinal X-ray examination showed a leakage of barium meal from the stomach to a huge abnormal cavity in the region of left hypochondrium. Exploratory laparotomy revealed a large leiomyosarcoma associated with central necrosis, forming a fistula protruding into the gastric lumen. Characteristic findings of the three kinds of imaging diagnostics in these tumors were as follows: Leiomyoma: With US, the abdominal tumor produced a cystic homogeneous echo pattern scattered with hyperechoic spots. With Ct, smooth, homogeneous and low density areas were seen and these were homogeneously enhanced by contrast media. With AG, vessels around the tumor were ring-shaped, and the tumor was clearly and homogeneously stained at venous phase. The diagnosis of the primary tumor was easy to make through identification of the tumor's feeding arteries. Leimyosarcoma: US indicated a tumor mixed with non-homogeneous solid and cystic patterns. In part of the tumor and in a metastatic lesion in the liver, hyperechoic rims and central sonolucent caviation were seen. With CT, the tumor showed non-homogeneous low densities, and their margins were irregular and undefined, which were emphasized by contrast media. Angiographically, vessels surrounding the tumor were found to be irregular. In the venous phase, the tumor stain was also irregular and non-homogeneous. The diagnosis of the primary tumor was difficult to make using any of the methods. (J.P.N.)

  12. Intracranial infective aneurysms presenting with haemorrhage: An analysis of angiographic findings, management and outcome

    International Nuclear Information System (INIS)

    AIM: This study is an analysis of angiographic findings in 17 patients with infective aneurysms who presented with intracranial haemorrhage and reviews the management and outcome in the context of the existing literature. MATERIALS AND METHODS: A retrospective study of infective aneurysms in 17 patients was carried out. Cranial angiography was performed in all patients. The location, size and outline of aneurysms were analysed. Ten patients were managed conservatively and six patients underwent surgery for the ruptured infective aneurysms and were followed up for a period of 35.8 months and 23 months, respectively. RESULTS: Twenty-two aneurysms were identified (five unruptured) in 17 patients. Twenty aneurysms (90.9%) were distal in location and two (9.1%) proximal. Sixty percent were in the posterior circulation with 55% in the posterior cerebral artery (PCA) territory, 27.3% in the middle cerebral artery (MCA) territory and 9.1% in the anterior cerebral artery (ACA) territory. Fourteen aneurysms were small (3-5 mm) and eight were medium sized (6-9 mm). 72.7% of aneurysms had irregular outline and 27.3% regular outline. Out of the 10 ruptured aneurysms managed conservatively, eight resolved. One patient died, presumably due to rebleed, and one had infarction due to parent vessel thrombosis. Six aneurysms were surgically managed with good results. Of the five unruptured aneurysms one was surgically managed and the remaining four conservatively managed patients did not bleed during follow-up. CONCLUSION: Patients with ruptured infective aneurysms fared well with medical management and the outcome in this series is better than that reported in literature. Patients on conservative management, however, need closer monitoring with angiographic follow-up. Active management is required with enlarging or persisting aneurysms. Venkatesh, S.K. (2000)

  13. Hepatocellular Carcinoma with Blood Supply from Parasitized Omental Artery: Angiographic Appearance And Chemoembolization

    Institute of Scientific and Technical Information of China (English)

    Song Gao; Ren-jie Yang; Jia-hong Dong

    2012-01-01

    Objective:To analyze angiographic appearance of hepatocellular carcinoma (HCC) with blood supply from parasitized omental artery (POA),and evaluate the technical feasibility,safety and therapeutic efficacy of chemoembolization via the POAs.Methods:A total of 1,221 HCC patients who had undergone chemoembolization procedures were evaluated retrospectively.The evaluated indexes included the incidence rate of POAs,success rate of superselective catheterization,post-reaction after chemoembolization,and the cumulative survival rates.Results:Totally 1,221 HCC patients had undergone 3,639 chemoembolization procedures,and 32 patients with POAs were enrolled,with 97 POAs found in 76 angiography procedures,giving an incidence rate of 2.09%.POA was observed mostly at the right lobe and left medial lobe except the segment Ⅱ,and 62 POAs underwent superselective catheterization with microcatheter,giving a success rate of 63.9%.The angiographic appearance was:(1) hypertrophic POAs participating in tumor staining (n=28); (2) stiff and distorted POA (n=11),displaced due to tumor's oppression (n=8); and (3) defective tumor staining close to either gastrocolic omentum distribution or liver capsule (n=7).In 19 patients,chemoembolization via POAs was performed successfully (A group),while the remaining 13 patients failed (B group).Except 1 acute edema pancreatitis case,no serious complication was recorded.The cumulative survival rates of 6-,12-,18-and 24-month were 78.9%,47.4%,31.6% and 21.1% respectively for A group; correspondingly,61.5%,30.g%,15.4% and 7.7%% for B group,in which 2 patients died of ruptured HCC.Conclusion:Chemoembolization with microcatheter via POAs is a relatively safe,feasible and valuable method.

  14. Radiation doses and estimated risk from angiographic projections during coronary angiography performed using novel flat detector.

    Science.gov (United States)

    Varghese, Anna; Livingstone, Roshan S; Varghese, Lijo; Kumar, Parveen; Srinath, Sirish Chandra; George, Oommen K; George, Paul V

    2016-01-01

    Coronary angiography (CA) procedure uses various angiographic projections to elicit detailed information of the coronary arteries with some steep projections involving high radiation dose to patients. This study intends to evaluate radiation doses and estimated risk from angiographic projections during CA procedure performed using novel flat detector (FD) system with improved image processing and noise reduction techniques. Real-time monitoring of radiation doses using kerma-area product (KAP) meter was performed for 140 patients using Philips Clarity FD system. The CA procedure involved seven standard projections, of which five were extensively selected by interventionalists. Mean fluoroscopic time (FT), KAP, and reference air kerma (Ka,r) for CA procedure were 3.24 min (0.5-10.51), 13.99Gycm2 (4.02-37.6), and 231.43 mGy (73.8-622.15), respectively. Effective dose calculated using Monte Carlo-based PCXMC software was found to be 4.9mSv. Left anterior oblique (LAO) 45° projection contributed the highest radiation dose (28%) of the overall KAP. Radiation-induced risk was found to be higher in females compared to males with increased risk of lung cancer. An increase of 10%-15% in radiation dose was observed when one or more additional projections were adopted along with the seven standard projections. A 14% reduction of radiation dose was achieved from novel FD system when low-dose protocol during fluoroscopy and medium-dose protocol during cine acquisitions were adopted, compared to medium-dose protocol. PMID:27167263

  15. Pediatric vascular access

    International Nuclear Information System (INIS)

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  16. Pediatric vascular access

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, James S. [Northwestern University, Feinberg School of Medicine, Department of Medical Imaging, Children' s Memorial Hospital, Chicago, IL (United States)

    2006-05-15

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  17. Prevalence and Molecular Analysis of Occult Hepatitis B Virus Infection Isolated in a Sample of Cryptogenic Cirrhosis Patients in Iran

    OpenAIRE

    Fatemeh Akhavan Anvari; Seyed Moayyed Alavian; Mehdi Norouzi; Mostafa Mahabadi; Seyed Mohammad Jazayeri

    2014-01-01

    Objectives: The aims of this study are to investigate the prevalence of occult hepatitis B virus infection among patients with cryptogenic cirrhosis and to analyze the relationship between surface protein variability and occult hepatitis B virus infection, which may be related to the pathogenesis of occult hepatitis B virus infection in cryptogenic cirrhosis. Occult hepatitis B virus infection is a well-recognized clinical entity characterized by the detection of hepatitis B virus DNA in seru...

  18. Dynamical performance for science-mode stationkeeping with an external occulter

    DEFF Research Database (Denmark)

    Sirbu, Dan; Karsten, Christian Vad; Kasdin, N Jeremy

    2010-01-01

    An external occulter flown in precise formation with a telescope is being considered for high-contrast direct imaging of exoplanets as a viable mission scenario. In this paper, the dynamics about the Sun-Earth L2 region for an occulter-telescope constellation are considered in conjunction with...

  19. Incidentaloma at Radial Artery Forearm Free Flap Harvest: An Occult Volar Wrist Ganglion

    OpenAIRE

    Nambi, G.I.; M Dhiwakar

    2012-01-01

    Occult volar wrist ganglion originating from radioscaphoid interval and having adherence to flexor carpi radialis tendon [Fcr] and radial artery is an uncommon occurrence. We report such a case which was occult and asymptomatic during pre-operative assessment and presented as an incidentaloma during radial artery forearm free flap harvest for oral cancer reconstruction.

  20. Advanced Electrocardiography Can Identify Occult Cardiomyopathy in Doberman Pinschers

    Science.gov (United States)

    Spiljak, M.; Petric, A. Domanjko; Wilberg, M.; Olsen, L. H.; Stepancic, A.; Schlegel, T. T.; Starc, V.

    2011-01-01

    Recently, multiple advanced resting electrocardiographic (A-ECG) techniques have improved the diagnostic value of short-duration ECG in detection of dilated cardiomyopathy (DCM) in humans. This study investigated whether 12-lead A-ECG recordings could accurately identify the occult phase of DCM in dogs. Short-duration (3-5 min) high-fidelity 12-lead ECG recordings were obtained from 31 privately-owned, clinically healthy Doberman Pinschers (5.4 +/- 1.7 years, 11/20 males/females). Dogs were divided into 2 groups: 1) 19 healthy dogs with normal echocardiographic M-mode measurements: left ventricular internal diameter in diastole (LVIDd . 47mm) and in systole (LVIDs . 38mm) and normal 24-hour ECG recordings (100 VPCs/24h; 1/12 dogs had only abnormal 24-hour ECG recordings (>100 VPCs/24h). ECG recordings were evaluated via custom software programs to calculate multiple parameters of high-frequency (HF) QRS ECG, heart rate variability, QT variability, waveform complexity and 3-D ECG. Student's t-tests determined 19 ECG parameters that were significantly different (P ECG parameters could identify occult ECG with sensitivity 89% and specificity 83%. Results suggest that 12-lead A-ECG might improve diagnostic value of short-duration ECG in earlier detection of canine DCM as five selected ECG parameters can with reasonable accuracy identify occult DCM in Doberman Pinschers. Future extensive clinical studies need to clarify if 12-lead A-ECG could be useful as an additional screening test for canine DCM.

  1. Magnetic resonance imaging of occult fractures of the proximal femur

    International Nuclear Information System (INIS)

    The evaluation of the painful hip in the elderly osteoporotic patient with normal plain radiographs can be difficult. We studied 15 osteopenic patients with normal plain radiographs and suspected hip fractures with magnetic resonance (MR) imaging and found MR to be an excellent aid in detecting occult fractures. A clear fracture was seen in 10 of the 15 patients, who then underwent surgical repair based on the MR study. The remaining patients had no MR-demonstrable fracture and were successfully treated nonoperatively. Some believe that a negative bone scan in this population of patients should be repeated within 3 days prior to a definitive ''no fracture'' decision being made. Unfortunately, bone scanning lacks spatial resolution, and increased osteoblastic activity may be caused by other pathologic processes besides fracture. Two of the 15 patients had MR-demonstrated bone infarcts near the fracture. One patient also had femoral head osteonecrosis on the side of the fracture. One patient with metastatic prostatic carcinoma had a hip fracture and one patient with metastatic breast carcinoma had no fracture. Not only is MR imaging an excellent technique for delineating occult fractures, but due to its spatial resolution, associated bone disorders adjacent to fractures can be detected in most instances. From a cost perspective, rapid diagnosis and early treatment of an occult femoral fracture is advisable. A reduced hospital stay pending diagnosis and the early institution of definitive therapy also decrease the chance that a simple non-displaced fracture will displace and require more complex management with resultant increased morbidity and cost. We propose that, especially in elderly, osteopenic patients with normal plain radiographs and a high index of suspicion for hip fracture, MR can serve as the sole additional imaging study in most instances. (orig.)

  2. Interpretation of gravity wave signatures in GPS radio occultations

    Science.gov (United States)

    Alexander, P.; de la Torre, A.; Llamedo, P.

    2008-08-01

    The horizontal averaging of global positioning system radio occultation retrievals produces an amplitude attenuation and phase shift in any plane gravity wave, which may lead to significant discrepancies with respect to the original values. In addition, wavelengths cannot be straightforwardly inferred due to the observational characteristics. If the waves produce small departures from spherical symmetry in the background atmosphere and under the assumption that the refractivity kernel may be represented by a delta function, an analytical expression may be derived in order to find how the retrieved amplitudes become weakened (against the original ones). In particular, we study the range of waves that may be detected and the consequent reduction in variance calculation, which is found to be around 19%. A larger discrepancy was obtained when comparing an occultation variance with the one computed from a numerical simulation of that case. Wave amplitudes can be better resolved when the fronts are nearly horizontal or when the angle between the occultation line of sight and the horizontal component of the wave vector approaches π/2. Short horizontal scale waves have a high probability of becoming attenuated or of not being detected at all. We then find geometrical relations in terms of the relative orientation between waves and sounding, so as to appropriately interpret wavelengths extracted from the acquired data. Only inertio-gravity waves, which exhibit nearly horizontal fronts, will show small differences between detected and original vertical wavelengths. Last, we analyze the retrieval effect on wave phase and find a shift between original and detected wave that generally is nonzero and approaches π/4 for the largest horizontal wavelengths.

  3. Radio Occultation Investigation of the Rings of Saturn and Uranus

    Science.gov (United States)

    Marouf, Essam A.

    1997-01-01

    The proposed work addresses two main objectives: (1) to pursue the development of the random diffraction screen model for analytical/computational characterization of the extinction and near-forward scattering by ring models that include particle crowding, uniform clustering, and clustering along preferred orientations (anisotropy). The characterization is crucial for proper interpretation of past (Voyager) and future (Cassini) ring, occultation observations in terms of physical ring properties, and is needed to address outstanding puzzles in the interpretation of the Voyager radio occultation data sets; (2) to continue the development of spectral analysis techniques to identify and characterize the power scattered by all features of Saturn's rings that can be resolved in the Voyager radio occultation observations, and to use the results to constrain the maximum particle size and its abundance. Characterization of the variability of surface mass density among the main ring, features and within individual features is important for constraining the ring mass and is relevant to investigations of ring dynamics and origin. We completed the developed of the stochastic geometry (random screen) model for the interaction of electromagnetic waves with of planetary ring models; used the model to relate the oblique optical depth and the angular spectrum of the near forward scattered signal to statistical averages of the stochastic geometry of the randomly blocked area. WE developed analytical results based on the assumption of Poisson statistics for particle positions, and investigated the dependence of the oblique optical depth and angular spectrum on the fractional area blocked, vertical ring profile, and incidence angle when the volume fraction is small. Demonstrated agreement with the classical radiative transfer predictions for oblique incidence. Also developed simulation procedures to generate statistical realizations of random screens corresponding to uniformly packed

  4. External occulter edge scattering control using metamaterials for exoplanet detection

    Science.gov (United States)

    Bendek, Eduardo A.; Sirbu, Dan; Liu, Zhaowei; Martin, Stefan; Lu, Dylan

    2015-09-01

    Direct imaging of earth-like exoplanets in the Habitable Zone of sun-like stars requires image contrast of ~10^10 at angular separations of around a hundred milliarcseconds. One approach for achieving this performance is to fly a starshade at a long distance in front of the telescope, shading the telescope from the direct starlight, but allowing planets around the star to be seen. The starshade is positioned so that sunlight falls on the surface away from the telescope, so the sun does not directly illuminate it. However, sunlight scattered from the starshade edge can enter the telescope, raising the background light level and potentially preventing the starshade from delivering the required contrast. As a result, starshade edge design has been identified as one of the highest priority technology gaps for external occulter missions in the NASAs Exoplanet Exploration Program Technology Plan 2013. To reduce the sunlight edge scatter to an acceptable level, the edge Radius Of Curvature (ROC) should be 1μm or less (commercial razor blades have ROC of a few hundred nanometer). This poses a challenging manufacturing requirement and may make the occulter difficult to handle. In this paper we propose an alternative approach to controlling the edge scattering by applying a flexible metamaterial to the occulter edge. Metamaterials are artificially structured materials, which have been designed to display properties not found in natural materials. Metamaterials can be designed to direct the scatter at planned incident angles away from the space telescope, thereby directly decreasing the contaminating background light. Reduction of the background light translates into shorter integration time to characterize a target planet and therefore improves the efficiency of the observations. As an additional benefit, metamaterials also have potential to produce increased tolerance to edge defects.

  5. Buoyancy waves in Pluto's high atmosphere: Implications for stellar occultations

    OpenAIRE

    Hubbard, W. B.; McCarthy, D. W.; Kulesa, C. A.; Benecchi, S. D.; Person, M. J.; Elliot, J. L.; Gulbis, A.A.S.

    2009-01-01

    We apply scintillation theory to stellar signal fluctuations in the high-resolution, high signal/noise, dual-wavelength data from the MMT observation of the 2007 March 18 occultation of P445.3 by Pluto. A well-defined high wavenumber cutoff in the fluctuations is consistent with viscous-thermal dissipation of buoyancy waves (internal gravity waves) in Pluto’s high atmosphere, and provides strong evidence that the underlying density fluctuations are governed by the gravity-wave dispersion rela...

  6. Combined parathyroid adenoma and an occult papillary carcinoma

    International Nuclear Information System (INIS)

    Although the pathological association of thyroid and parathyroid disease is common, the association of both parathyroid adenoma and thyroid cancer is rare. We report here a case of a 45-year-old saudi women who diagnosed to have primary hyperparathyrodism due to single parathyroid adenoma as confirmed biochemically and radiologically. At operation, the adenoma was found to be an intrathyroid and therefore a thyroid lobectomy was performed. Histology of the excised lobe revealed in addition to the intrathyroid parathyroid adenoma a concurrent occult thyroid papillary carcinoma. The interesting association is discussed based on a literature review. (author)

  7. The significance of mammographic signs in clinically occult disease

    International Nuclear Information System (INIS)

    The significance of various radiographic signs in 183 patients with clinically occult breast disease is described. 30.6% hat a carcinoma of the breast or a carcinoma in situ. The radiological features have varying predictive values and there is variation in the incidence of lymph node metastases. It is considered useful to classify the radiological appearances under the headings of round foci, star-shaped opacities, diffuse opacities, opacities with calcification and groups of micro-calcification. Despite the early diagnosis, 24% of patients already had lymph node metastases. (orig.)

  8. Presentation of occult Chiari I malformation following spinal anesthesia

    Directory of Open Access Journals (Sweden)

    Saravanan P Ankichetty

    2012-01-01

    Full Text Available Chiari I malformation (CM-I manifests with tonsillar herniation below foramen magnum. These patients are at high risk of respiratory depression and bulbar dysfunction in the perioperative period with underlying obstructive sleep apnea. However, the safe use of both general and regional anaesthesia has been documented in a known CM-I parturients. We describe the successful management of a patient who had hypercapnic respiratory failure in the post-anaesthetic care unit following an uneventful subarachnoid block for left knee replacement surgery. This patient was retrospectively diagnosed with occult CM-I and moderate to severe obstructive sleep apnea in the postoperative period.

  9. Upper tibial hyperextension fractures in infants: another occult toddler's fracture

    International Nuclear Information System (INIS)

    We describe the radiographic findings associated with occult upper tibial fractures in infants and young children and offer an explanation for the underlying mechanism from which they result. These fractures tend to be subtle, just as the classic spiral tibial fracture originally described by Dunbar et al. (1964, J Can Assoc Radiol 15: 136-144). The fracture we describe results from a hyperextension injury to the knee, and the knowledge of the mechanism of injury, the subtle radiographic findings, and the findings on physical examination allow one to diagnose this fracture with confidence. Otherwise, it easily can go undetected. (orig.)

  10. Occult hepatitis B virus infection and blood transfusion

    OpenAIRE

    Seo, Dong Hee; Whang, Dong Hee; Song, Eun Young; Han, Kyou Sup

    2015-01-01

    Transfusion-transmitted infections including hepatitis B virus (HBV) have been a major concern in transfusion medicine. Implementation of HBV nucleic acid testing (NAT) has revealed occult HBV infection (OBI) in blood donors. In the mid-1980s, hepatitis B core antibody (HBc) testing was introduced to screen blood donors in HBV non-endemic countries to prevent transmission of non-A and non-B hepatitis. That test remains in use for preventing of potential transmission of HBV from hepatitis B su...

  11. Rosemary Hill Observatory lunar occultation summary for 1983-1984

    Science.gov (United States)

    Schneider, Glenn; Anderson, Chris

    1993-04-01

    The results from photometric observations of 21 previously unreported occultation disappearances obtained during the period from March 24, 1983 through March 12, 1984, with the University of Florida's Rosemary Hill Observatory 76-cm reflecting telescope are presented. Statistically significant determinations of stellar diameters are indicated for two stars: 32 Librae (12.2 mas) and BD + 22 deg 1032 (5.45 mas). Diameter measurements of marginal statistical significance are noted for two other stars (9 Cancri and 37 Capricorni). New duplicity determinations are reported for five stellar systems in this sample.

  12. Victor Brauner and the Surrealist Interest in the Occult

    OpenAIRE

    Darie, Camelia Dana

    2012-01-01

    My research on Victor Brauner’s work in the first two decades of his affiliation with the Surrealist group in Paris re-establishes the role played by the Romanian Jewish artist in the definition of automatic Surrealist procedures of painting and mixed-technique objects that relied upon a new and unconventional understanding of the occult.In the three chapters of this study of Victor Brauner’s work in the 1930s and early 1940s, I analyse key notions, such as the fantastic, animal magnetism, an...

  13. Sporadic E Morphology from GPS-CHAMP Radio Occultation

    Science.gov (United States)

    Wu, Dong L.; Ao, Chi O.; Hajj, George A.; de la Torre Juarez, Manuel; Mannucci, Anthony J.

    2005-01-01

    The scintillations of phase and amplitude in terms of signal-to-noise ratio (SNR) of the GPS radio occultation signal are caused by thin ionization layers. These thin irregular electron density layers in the E region ionosphere are often called sporadic E (Es). For a monthly retrieval of Es morphology we use the variances of the phase and SNR fluctuations of worldwide 6000 GPS/CHAMP occultations in the E region. The Es climatology is studied globally with the SNR and phase variances in terms of monthly zonal means, seasonal maps, and diurnal and long-term variations. The zonal mean variances reveal strong, extended Es activities at summertime midlatitudes but weak, confined activities in wintertime high latitudes, peaking at 105 km. Global maps at 105-km altitude show clear dependence of Es activities on the geomagnetic dip angle, where the summertime midlatitude Es occurs mostly at dip angles of 30 deg. - 60 deg. and the wintertime high-latitude enhancement occurs mostly at dip angles greater than 80 deg. The midlatitude Es variances exhibit a strong semidiurnal variation with peak hours near 0800 1000 and 2000 local solar time, respectively. The peak hours are delayed slightly with decreasing height, suggesting influences from the semidiurnal tide. To provide more insights on the observed SNR and phase variances, we model radio wave propagation for the CHAMP observing geometry under several perturbed cases in the E region ionosphere. The model simulations indicate that the SNR variance has the maximum response to Es perturbations at vertical wavelengths of 1.2 km, whereas the phase response maximizes at 2 km (for the 1-s variance analysis). The characteristic scale depends little on the truncation time used in the SNR variance analysis, but it increases with the truncation time for the phase variances. Initial studies show that reasonable global Es morphology can be produced on a monthly and seasonal basis with the CHAMP one-antenna occultations. Better results

  14. Isolated hemolytic anemia: an unusual manifestation of occult malignancy

    Directory of Open Access Journals (Sweden)

    Matthew J. Butler

    2014-02-01

    Full Text Available Hemolysis is an uncommon and usually late complication of malignancy, and very rarely the presenting feature. Cancer-associated hemolysis may be immune-mediated, or may result from thrombotic microangiopathy accompanied by thrombocytopenia. We describe an unusual case of isolated hemolysis in the setting of occult metastatic breast cancer. The patient initially presented with symptomatic anemia, with evidence of hemolysis but with negative direct antiglobulin testing and a normal platelet count. Subsequent investigation discovered metastatic adenocarcinoma of the breast involving bone marrow. Hemolysis worsened despite initial treatment with cytotoxic chemotherapy and a trial of corticosteroids, but later resolved with aromatase inhibitor therapy.

  15. Detection of Small Kuiper Belt Objects by Stellar Occultations

    OpenAIRE

    Stevenson, R

    2007-01-01

    Knowledge of the Kuiper Belt is currently limited to those objects that can be detected directly. Objects with diameters less than $\\sim$10km reflect too little light to be detected. These smaller bodies could contain most of the mass in the Kuiper Belt while the abundance of these bodies may constrain the distribution of mass. The overall size distribution of bodies within the Kuiper Belt can also be inferred from the relative abundances of sub-km and larger bodies. Stellar occultations are ...

  16. Occult fracture of the calcaneus - another Toddler's fracture

    International Nuclear Information System (INIS)

    Fractures of the calcaneus have been considered rare among children. We feel this may be erroneous since in the last 12 months we have seen 10 such fractures among children, 19 and 41 months of age, who presented with acute limping. The fractures were detected with bone imaging which was performed when initial radiographs were noncontributory. Subsequent radiographs of the calcaneus were positive for fracture in 4 to 10 while follow up radiographs confirmed healing fractures in the two children so evaluated. The sensitivity of bone imaging for the detection of occult fractures in toddlers is emphasized. (orig.)

  17. Categorizing the Occult: Vodun, Sorcery and Religious Beliefs In Benin

    DEFF Research Database (Denmark)

    Strandsbjerg, Camilla

    2011-01-01

    magic, the mystical and the “occult” and particularly the difficulties of transmission in analytical terms of these phenomena have accompanied the production of anthropological knowledge since the early days of the discipline. However, in Benin, researchers in all domains of life are continuously...... the popular and academic understanding of three key terms (vodun, sorcery and occult). The paper will thus both focus on the role of religious encounters during early Christian missions in Benin and on the recent expansion of evangelical churches and strengthen of neo vodun cults as well as on the...

  18. Occult lung malignancy presenting with finger pain: a case report

    Directory of Open Access Journals (Sweden)

    Embley Matthew A

    2008-12-01

    Full Text Available Abstract Introduction Lung cancer is currently one of the most common malignancies in the world. Early detection is an important prognostic factor. Unfortunately, initial symptoms may be vague and a substantial proportion of cases present with the effects of metastases. Case presentation We discuss a case of occult lung malignancy in a 61-year-old man. The only symptom at presentation was pain in the right ring finger due to metastasis from the lung primary. Conclusion This case highlights the need for vigilance when a patient presents with unusual or unexplained symptoms, especially if they have known risk factors for cancer.

  19. JWST observations of stellar occultations by solar system bodies and rings

    CERN Document Server

    Santos-Sanz, P; Pinilla-Alonso, N; Stansberry, J; Lin, Z-Y; Zhang, Z-W; Vilenius, E; Müller, Th; Ortiz, J L; Braga-Ribas, F; Bosh, A; Duffard, R; Lellouch, E; Tancredi, G; Young, L

    2015-01-01

    In this paper we investigate the opportunities provided by the James Webb Space Telescope (JWST) for significant scientific advances in the study of solar system bodies and rings using stellar occultations. The strengths and weaknesses of the stellar occultation technique are evaluated in light of JWST's unique capabilities. We identify several possible JWST occultation events by minor bodies and rings, and evaluate their potential scientific value. These predictions depend critically on accurate a priori knowledge of the orbit of JWST near the Sun-Earth Lagrange-point 2 (L2). We also explore the possibility of serendipitous stellar occultations by very small minor bodies as a by-product of other JWST observing programs. Finally, to optimize the potential scientific return of stellar occultation observations, we identify several characteristics of JWST's orbit and instrumentation that should be taken into account during JWST's development.

  20. Detectability of Occultation of Stars by Objects in the Kuiper Belt and Oort Cloud

    CERN Document Server

    Nihei, T C; Bianco, F B; King, S K; Giammarco, J M; Alcock, C

    2007-01-01

    The serendipitous detection of stellar occultations by Outer Solar System objects is a powerful method for ascertaining the small end ($r \\lesssim 15$ km) of the size distribution of Kuiper Belt Objects and may potentially allow the exploration of objects as far out as the Oort Cloud. The design and implementation of an occultation survey is aided by a detailed understanding of how diffraction and observational parameters affect the detection of occultation events. In this study, stellar occultations are simulated, accounting for diffraction effects, finite source sizes, finite bandwidths, stellar spectra, sampling, and signal-to-noise. Finally, the possibility of detecting small Outer Solar System objects from the Kuiper Belt all the way out to the Oort Cloud is explored for three photometric systems: a proposed space telescope, Whipple (Kaplan et al. 2003), the Taiwanese-American Occultation Survey (Lehner et al. 2006), and the Multi Mirror Telescope (Bianco 2007).

  1. Wave propagation simulation of radio occultations based on ECMWF refractivity profiles

    DEFF Research Database (Denmark)

    von Benzon, Hans-Henrik; Høeg, Per

    2015-01-01

    This paper describes a complete radio occultation simulation environment, including realistic refractivity profiles, wave propagation modeling, instrument modeling, and bending angle retrieval. The wave propagator is used to simulate radio occultation measurements. The radio waves are propagated...... radio occultations. The output from the wave propagator simulator is used as input to a Full Spectrum Inversion retrieval module which calculates geophysical parameters. These parameters can be compared to the ECMWF atmospheric profiles. The comparison can be used to reveal system errors and get a...... better understanding of the physics. The wave propagation simulations will in this paper also be compared to real measurements. These radio occultations have been exposed to the same atmospheric conditions as the radio occultations simulated by the wave propagator. This comparison reveals that precise...

  2. Congenital Vascular Malformation

    Science.gov (United States)

    ... clots, obstruction of major vessels, causing progressive limb asymmetry by overgrowth, and for cosmetic indications or because ... t he Vascular Disease Foundation (VDF) develops educational information and initiatives for patients, their families and friends, ...

  3. Vascular Access for Hemodialysis

    Science.gov (United States)

    ... for short-term use. [ Top ] What is an arteriovenous fistula? An AV fistula is a connection, made by ... to remove and return blood during hemodialysis. An arteriovenous (AV) fistula is a connection, made by a vascular surgeon, ...

  4. Heart and vascular services

    Science.gov (United States)

    ... Repair of aneurysms (dilated/enlarged portions) of the aorta and its branches Procedures may also be used ... Nutrition and lifestyle counseling, including smoking cessation and diabetes education Supervised exercise Alternative Names Circulatory system; Vascular ...

  5. Management of Vascular Malformations

    Directory of Open Access Journals (Sweden)

    Sadanori Akita, MD, PhD

    2014-03-01

    Conclusions: Treatment of vascular malformations is an integral part of multidisciplinary approaches. Venous malformations are more frequent in combination surgery, and if there are fewer complications, the patients’ satisfaction increases.

  6. Categorical course in neuroradiology cerebral ischemia, hemorrhage, and vascular lesions

    International Nuclear Information System (INIS)

    The diagnostic imaging of acute stroke is primarily directed toward identifying the lesion, characterizing it as either intracranial hemorrhage or ischemia, and assessing the anatomic extent of the lesion. The acute medical or surgical management decisions are best aided by a combination of CT and cerebral angiography, the latter used acutely mostly for intracranial hemorrhage, especially subarachnoid hemorrhage. More complex presentations benefit from MR imaging evaluation as well. After the acute phase, the main goal of treatment, especially for patients who have had reasonable recovery from the acute stroke, is the prevention of recurrent, and perhaps more severe, stroke. Treatments such as aneurysm clipping or arteriovenous malformation removal for hemorrhagic lesions, or anticoagulation or carotid endarterectomy for ischemic lesions, require brain and vascular imaging studies for appropriate treatment planning. Angiography to show the anatomic vascular cause for the bleed or ischemia is therefore usually a requirement. The enlarging experience with MR imaging has contributed greatly to the identification of occult vascular lesions of the brain that may be prone to bleeding and to recognizing blood in the brain accurately. For this purpose MR imaging is sometimes more specific than CT

  7. Prevention of cardiac complications in peripheral vascular surgery

    International Nuclear Information System (INIS)

    The prevalence of severe coronary artery disease in peripheral vascular patients exceeds 50 per cent. Complications of coronary artery disease are the most common causes of mortality following peripheral vascular operations. To reduce the incidence of cardiac complications, it is first necessary to identify patients at risk through screening tests. Screening methods in current use include risk factor analysis, exercise testing, routine coronary angiography, and dipyridamole thallium-201 scintigraphy. The risk factor approach has the advantage of being widely applicable since it makes use of historical, physical, and electrocardiographic findings that are already familiar to surgeons and anesthesiologists. It is also inexpensive. However, it may overlook the patient who has no symptoms of coronary artery disease, possibly as a result of the sedentary lifestyle imposed by complications of peripheral vascular disease. The electrocardiographically monitored stress test will identify the asymptomatic patient with occult coronary disease and is helpful in predicting operative risk. However, a meaningful test is dependent on the patient's ability to exercise--an activity that is frequently limited by claudication, amputation, or arthritis. Exercise testing also suffers from a lack of sensitivity and specificity when compared with coronary arteriography. Routine preoperative coronary angiography overcomes the exercise limitation of treadmill testing but is not widely applicable as a screening test for reasons of cost and inherent risk. Dipyridamole thallium-201 scanning, on the other hand, is safe and of relatively low cost and does not require exercise

  8. Prevention of cardiac complications in peripheral vascular surgery

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, B.S.

    1986-04-01

    The prevalence of severe coronary artery disease in peripheral vascular patients exceeds 50 per cent. Complications of coronary artery disease are the most common causes of mortality following peripheral vascular operations. To reduce the incidence of cardiac complications, it is first necessary to identify patients at risk through screening tests. Screening methods in current use include risk factor analysis, exercise testing, routine coronary angiography, and dipyridamole thallium-201 scintigraphy. The risk factor approach has the advantage of being widely applicable since it makes use of historical, physical, and electrocardiographic findings that are already familiar to surgeons and anesthesiologists. It is also inexpensive. However, it may overlook the patient who has no symptoms of coronary artery disease, possibly as a result of the sedentary lifestyle imposed by complications of peripheral vascular disease. The electrocardiographically monitored stress test will identify the asymptomatic patient with occult coronary disease and is helpful in predicting operative risk. However, a meaningful test is dependent on the patient's ability to exercise--an activity that is frequently limited by claudication, amputation, or arthritis. Exercise testing also suffers from a lack of sensitivity and specificity when compared with coronary arteriography. Routine preoperative coronary angiography overcomes the exercise limitation of treadmill testing but is not widely applicable as a screening test for reasons of cost and inherent risk. Dipyridamole thallium-201 scanning, on the other hand, is safe and of relatively low cost and does not require exercise.

  9. Vascular Effects of Histamine.

    Science.gov (United States)

    Ebeigbe, Anthony B; Talabi, Olufunke O

    2014-01-01

    Four subtypes of receptors (H1, H2, H3 and H4) mediate the actions of histamine. In the vascular wall, the effects of histamine are mediated via H1 and H2 receptors and the actions are modulated by H3 receptor subtype located on presynaptic neurones. Alterations in vascular responses to histamine are associated with experimental as well as a human form of hypertension, suggesting a role for histanine in cardiovascular regulation. PMID:26196559

  10. Thrombolysis in vascular surgery

    OpenAIRE

    Smith, Linn

    2015-01-01

    Background and aims: Thrombolysis is in common use in the treatment of acute forms of vascular disease. It may be used both systemically and locally, in the latter case through an endovascular approach, socalled catheter-directed thrombolysis. The aims of this thesis were to investigate how thrombolysis affects performance-related outcomes pertaining to vascular patency after thrombolysis, and how it affects patient safety and the development of complications. Metho...

  11. [Zaidemberg's vascularized radial graft].

    Science.gov (United States)

    Saint-Cast, Y

    2010-12-01

    In 1991, Carlos Zaidemberg described a new technique to repair scaphoid non-unions with a vascularized bone graft harvested from the radial styloid process. An anatomic study based on 30 dissections after colorized latex injection established the constancy of the radial styloid process's artery, while showing that its origin, course and length were subject to variations. In a retrospective series of 38 cases over a period of 10 years, the vascularized bone graft was indicated for: (1) scaphoid non-union with the presence of avascular changes of the proximal fragment (23 cases); (2) failed prior reconstruction with bone graft and internal fixation (nine cases); (3) degenerative styloid-scaphoid arthritis (three cases); (4) fracture on Preiser dystrophy (three cases). The five steps of the simplified operative technique without dissection of the vascular pedicle include: (1) longitudinal dorso-radial approach, identification of the periosteal portion of the radial styloid process artery; (2) incision of the first and second compartments, longitudinal arthrotomy under the second compartment; (3) styloidectomy and transversal resection of the scaphoid non-union and sclerotic bone; (4) elevation of the vascularized bone graft; (5) transversal and radial insertion of the vascularized bone graft, osteosynthesis by two or three K-wire touching the scaphoid's radial edge. Scaphoid union was obtained in 33 cases out of 38. The only postoperative complications were two transient radial paresthesia. The standardized surgical procedure using vascularized bone graft harvested from the radial styloid process provides an efficient scaphoid reconstruction. PMID:21087882

  12. CT herniography in the diagnosis of occult groin hernias

    Energy Technology Data Exchange (ETDEWEB)

    Markos, V. [Department of Radiology, Gloucester Royal Hospital, Gloucester (United Kingdom)]. E-mail: vmarkos@hotmail.com; Brown, E.F. [Department of Radiology, Gloucester Royal Hospital, Gloucester (United Kingdom)

    2005-02-01

    AIM: To evaluate the role of computed tomography (CT) after herniography in the diagnosis and management of primary and recurrent groin hernias not detectable on clinical examination. MATERIAL AND METHODS: Fifty-one patients underwent CT post-herniography over a 6-year period for suspected primary or recurrent inguinal hernia. The herniography and post-herniography CT findings were retrospectively compared with clinical and surgical follow-up. Statistical analysis was performed to assess the role of herniography and CT post-herniography in the primary and recurrent groups. RESULTS: Of the 51 patients investigated for occult inguinal hernia, 19 had previous hernia repair with possible recurrence. The most common symptom at presentation was groin pain or discomfort (84%). Seventy-five percent in the primary group and 84% in the recurrent group had no findings on herniography or CT. Nine percent in the primary group and 16% in the recurrent group had hernias diagnosed by herniography. CT did not enhance the detection of hernia. Sensitivity for herniography and CT herniography in the primary groin hernia group was 75% as against specificity, which was 100 and 90%, respectively. For the recurrent groin hernias, sensitivity was 60% for herniography and 40% for CT herniography and specificity 100% for both. CONCLUSION: CT performed post-herniography did not provide any benefit over performing herniography alone in the diagnosis of occult primary or recurrent inguinal hernias.

  13. CT herniography in the diagnosis of occult groin hernias

    International Nuclear Information System (INIS)

    AIM: To evaluate the role of computed tomography (CT) after herniography in the diagnosis and management of primary and recurrent groin hernias not detectable on clinical examination. MATERIAL AND METHODS: Fifty-one patients underwent CT post-herniography over a 6-year period for suspected primary or recurrent inguinal hernia. The herniography and post-herniography CT findings were retrospectively compared with clinical and surgical follow-up. Statistical analysis was performed to assess the role of herniography and CT post-herniography in the primary and recurrent groups. RESULTS: Of the 51 patients investigated for occult inguinal hernia, 19 had previous hernia repair with possible recurrence. The most common symptom at presentation was groin pain or discomfort (84%). Seventy-five percent in the primary group and 84% in the recurrent group had no findings on herniography or CT. Nine percent in the primary group and 16% in the recurrent group had hernias diagnosed by herniography. CT did not enhance the detection of hernia. Sensitivity for herniography and CT herniography in the primary groin hernia group was 75% as against specificity, which was 100 and 90%, respectively. For the recurrent groin hernias, sensitivity was 60% for herniography and 40% for CT herniography and specificity 100% for both. CONCLUSION: CT performed post-herniography did not provide any benefit over performing herniography alone in the diagnosis of occult primary or recurrent inguinal hernias

  14. The floating cardiac fat pad-sign of occult pneumothorax.

    Science.gov (United States)

    Kaufman, Claire; Bokhari, S A Jamal

    2016-08-01

    Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. PMID:27250975

  15. Image guidance improves localization of sonographically occult colorectal liver metastases

    Science.gov (United States)

    Leung, Universe; Simpson, Amber L.; Adams, Lauryn B.; Jarnagin, William R.; Miga, Michael I.; Kingham, T. Peter

    2015-03-01

    Assessing the therapeutic benefit of surgical navigation systems is a challenging problem in image-guided surgery. The exact clinical indications for patients that may benefit from these systems is not always clear, particularly for abdominal surgery where image-guidance systems have failed to take hold in the same way as orthopedic and neurosurgical applications. We report interim analysis of a prospective clinical trial for localizing small colorectal liver metastases using the Explorer system (Path Finder Technologies, Nashville, TN). Colorectal liver metastases are small lesions that can be difficult to identify with conventional intraoperative ultrasound due to echogeneity changes in the liver as a result of chemotherapy and other preoperative treatments. Interim analysis with eighteen patients shows that 9 of 15 (60%) of these occult lesions could be detected with image guidance. Image guidance changed intraoperative management in 3 (17%) cases. These results suggest that image guidance is a promising tool for localization of small occult liver metastases and that the indications for image-guided surgery are expanding.

  16. Occult hepatitis B virus infection and blood transfusion

    Institute of Scientific and Technical Information of China (English)

    Dong Hee Seo; Dong Hee Whang; Eun Young Song; Kyou Sup Han

    2015-01-01

    Transfusion-transmitted infections including hepatitis Bvirus (HBV) have been a major concern in transfusionmedicine. Implementation of HBV nucleic acid testing(NAT) has revealed occult HBV infection (OBI) in blooddonors. In the mid-1980s, hepatitis B core antibody(HBc) testing was introduced to screen blood donorsin HBV non-endemic countries to prevent transmissionof non-A and non-B hepatitis. That test remains inuse for preventing of potential transmission of HBVfrom hepatitis B surface antigen (HBsAg)-negativeblood donors, even though anti-hepatitis C virus testshave been introduced. Studies of anti-HBc-positivedonors have revealed an HBV DNA positivity rate of0%-15%. As of 2012, 30 countries have implementedHBV NAT. The prevalence of OBI in blood donors wasestimated to be 8.55 per 1 million donations, accordingto a 2008 international survey. OBI is transmissible byblood transfusion. The clinical outcome of occult HBVtransmission primarily depends on recipient immunestatus and the number of HBV DNA copies present in theblood products. The presence of donor anti-HBs reducesthe risk of HBV infection by approximately five-fold. Therisk of HBV transmission may be lower in endemic areasthan in non-endemic areas, because most recipientshave already been exposed to HBV. Blood safety forHBV, including OBI, has substantially improved, but thepossibility for OBI transmission remains.

  17. Comparison of ionospheric radio occultation CHAMP data with IRI 2001

    Directory of Open Access Journals (Sweden)

    N. Jakowski

    2004-01-01

    Full Text Available GPS radio occultation measurements on board low Earth orbiting satellites can provide vertical electron density profiles of the ionosphere from satellite orbit heights down to the bottomside. Ionospheric radio occultation (IRO measurements carried out onboard the German CHAMP satellite mission since 11 April 2001 were used to derive vertical electron density profiles (EDP’s on a routine basis. About 150 vertical electron density profiles may be retrieved per day thus providing a huge data basis for testing and developing ionospheric models. Although the validation of the EDP retrievals is not yet completed, the paper addresses a systematic comparison of about 78 000 electron density profiles derived from CHAMP IRO data with the International Reference Ionosphere (IRI 2001. The results are discussed for quite different geophysical conditions, e.g. as a function of latitude, local time and geomagnetic activity. The comparison of IRO data with corresponding IRI data indicates that IRI generally overestimates the upper part of the ionosphere whereas it underestimates the lower part of the ionosphere under high solar activity conditions. In a first order correction this systematic deviation could be compensated by introducing a height dependence correction factor in IRI profiling.

  18. Insensible and Inexplicable - On the Two Meanings of Occult

    Directory of Open Access Journals (Sweden)

    Florian Sprenger

    2015-09-01

    Full Text Available While the distinction between spiritualism and science was understood affirmatively as a demarcation of true science against pseudo-science, nowadays, after several Science Wars, it is obvious for us that this distinction does not correspond to the actual practices of science but reflects a work of ‘purification’ typical for modernity in the Latourian sense. In the physico-philosophical surroundings of this boundary epistemological foundations are shaped and modern science is constituted as the primary way to knowledge. Referring to studies on the history of the occult in the early modern period, the article shows that in order to understand the stakes of spiritualism and its technical or personal media we should trace back this boundary to a rarely recognized conceptual transformation of the ‘occult’. It shifts between insensible and inexplicable. Following this leading difference, the article traces its function in the emergence of early occultism, the debate between Leibniz and Newton, and the rise of modern spiritualism and its instrumental repertoire.

  19. Waves in the Martian Atmosphere: Results from MGS Radio Occultations

    Science.gov (United States)

    Flasar, F. M.; Hinson, D. P.; Tyler, G. L.

    1999-01-01

    Temperatures retrieved from Mars Global Surveyor radio occultations have been searched for evidence of waves. Emphasis has been on the initial series of occultations between 29 deg N and 64 deg S, obtained during the early martian southern summer, L(sub s) = 264 deg - 308 deg. The profiles exhibit an undulatory behavior that is suggestive of vertically propagating waves. wavelengths approximately 10 km are often dominant, but structure on smaller scales is evident. The undulatory structure is most pronounced between latitudes 29 deg N and 10 deg S, usually in regions of "interesting" topography, e.g., in the Tharsis region and near the edge of Syrtis Major. Several temperature profiles, particularly within 30 deg of the equator, exhibit lapse rates that locally become superadiabatic near the 0.4-mbar level or at higher altitudes. This implies that the waves are "breaking" and depositing horizontal momentum into the atmosphere. Such a deposition may play an important role in modulating the atmospheric winds, and characterizing the spatial and temporal distribution of these momentum transfers can provide important clues to understanding how the global circulation is maintained.

  20. Occult scapholunate ganglion: a cause of dorsal radial wrist pain.

    Science.gov (United States)

    Steinberg, B D; Kleinman, W B

    1999-03-01

    There are multiple causes for chronic dorsal wrist pain over the scapholunate ligament, including occult dorsal carpal ganglion cyst, scaphoid impaction syndrome, dorsal carpal capsulitis, distal posterior interosseous nerve syndrome, and dynamic scapholunate ligament instability. Patients with such pain often have normal x-rays. A retrospective study of 21 patients undergoing surgical exploration for chronic dorsal radial wrist pain who had no palpable cyst and normal x-rays revealed that 18 of the patients had occult scapholunate ganglion cysts or myxomatous degeneration within the scapholunate ligament. All had failed long-term conservative management. Surgery involved an approach through Langer's lines, resection of a large triangular portion of the capsule between the dorsal intercarpal and radiotriquetral ligaments, and tangential debridement of the area of myxoid degeneration proximal to the distal 2 to 3 mm of dorsal scapholunate interosseous ligament. None of the patients had scapholunate instability or scaphoid impacting syndrome. Of the 18 patients with histologically confirmed myxomatous changes in the scapholunate ligament, 16 had an excellent outcome as defined by rigorous criteria; 1 had a good outcome. There was 1 patient with a poor result. A compelling argument is made for surgical exploration of the scapholunate joint in patients with persistent dorsal radial wrist pain and scapholunate point tenderness. PMID:10194003

  1. Use of dispersion to eliminate multipath in planetary radio occultations

    International Nuclear Information System (INIS)

    During planetary atmospheric and ionospheric study through radio occultation of spacecraft, multipath propagation often occurs at several altitudes in the medium. Although the signals are then simultaneous in time, they are separate in frequency. It is shown that dispersion can be used to separate such signals because they are inherently single-valued with respect to a family of curves having dT/dF = lambdaD/V2 (where F = frequency, T = time, V = velocity normal to the limb, lambda = wavelength, and D = distance from the spacecraft to the limb plane). The concept underlying this corrective measure is much like that of an FM--CW radar wherein frequency separation is converted to time separation. Application of the recommended dispersion may eliminate a major form of multipath and permit signal detection by receivers employing phase-lock loops that depend for their action on the existence of only one frequency. This should facilitate the processing of open-loop recorded data and it might permit the closed-loop reception of multipath signals without loss of information, making possible the observation of radio occultations with signals from Earth to spacecraft. Heretofore, this approach has not shown promise in multipath situations. No specific processes or designs are given, but there is a practical discussion concerning the degree of accuracy that must be provided in flight and during postflight analysis

  2. Radio occultation data analysis by the radioholographic method

    Science.gov (United States)

    Hocke, K.; Pavelyev, A. G.; Yakovlev, O. I.; Barthes, L.; Jakowski, N.

    1999-10-01

    The radioholographic method is briefly described and tested by using data of 4 radio occultation events observed by the GPS/MET experiment on 9 February 1997. The central point of the radioholographic method (Pavelyev, 1998) is the generation of a radiohologram along the LEO satellite trajectory which allows the calculation of angular spectra of the received GPS radio wave field at the LEO satellite. These spectra are promising in view of detection, analysis and reduction of multipath/diffraction effects, study of atmospheric irregularities and estimation of bending angle error. Initial analysis of angular spectra calculated by the multiple signal classification (MUSIC) method gives evidence that considerable multibeam propagation occurs at ray perigee heights below 20 km and at heights around 80-120 km for the 4 GPS/MET occultation events. Temperature profiles obtained by our analysis (radioholographic method, Abel inversion) are compared with those of the traditional retrieval by the UCAR GPS/MET team (bending angle from slope of phase front, Abel inversion). In 3 of 4 cases we found good agreement (standard deviation σT~1.5°K between both retrievals at heights 0-30 km).

  3. Perfusion and kinetic variations of left ventricle after primary PCI for acute myocardial infarction: correlation between clinico-angiographic and scintigraphic parameters

    OpenAIRE

    E Varani; M Balducelli; Severi, S; A Patroncini; A Shoheib; Vecchi, G.; GR Lucchi; Aquilina, M.; C Corbelli; Casanova, R.; A Maresta

    2007-01-01

    Background: The aim of the present study was to evaluate which of theclinico-angiographic parameters of acute ischemic extension and efficacy ofreperfusion in AMI treated with primary PCI are predictive of infarct size andone month left ventricular ejection fraction (LVEF).Patients and Method: Thirty-five patients with first AMI treated withprimary PCI underwent two rest 99mTc-sestamibi gated SPECT, 4-6 days and 30-40days after PCI. Clinical, electrocardiographic, angiographic and scintigraph...

  4. Antioxidants and vascular health.

    Science.gov (United States)

    Bielli, Alessandra; Scioli, Maria Giovanna; Mazzaglia, Donatella; Doldo, Elena; Orlandi, Augusto

    2015-12-15

    Oxygen free radicals and other reactive oxygen species (ROS) are common products of normal aerobic cellular metabolism, but high levels of ROS lead to oxidative stress and cellular damage. Increased production of ROS favors vascular dysfunction, inducing altered vascular permeability and inflammation, accompanied by the loss of vascular modulatory function, the imbalance between vasorelaxation and vasoconstriction, and the aberrant expression of inflammatory adhesion molecules. Inflammatory stimuli promote oxidative stress generated from the increased activity of mitochondrial nicotinamide adenine dinucleotide phosphate oxidase, particularly of the Nox4 isoform, with the consequent impairment of mitochondrial β-oxidation. Vascular dysfunction due to the increase in Nox4 activity and ROS overproduction leads to the progression of cardiovascular diseases, diabetes, inflammatory bowel disease, and neurological disorders. Considerable research into the development of effective antioxidant therapies using natural derivatives or new synthetic molecules has been conducted. Antioxidants may prevent cellular damage by reducing ROS overproduction or interfering in reactions that involve ROS. Vitamin E and ascorbic acid are well known as natural antioxidants that counteract lipid peroxidative damage by scavenging oxygen-derived free radicals, thus restoring vascular function. Recently, preliminary studies on natural antioxidants such as goji berries, thymus, rosemary, green tea ginseng, and garlic have been conducted for their efficacy in preventing vascular damage. N-acetyl-cysteine and propionyl-L-carnitine are synthetic compounds that regulate ROS production by replacing endogenous antioxidants in both endothelial and smooth muscle cells. In this review, we consider the molecular mechanisms underlying the generation of oxidative stress-induced vascular dysfunction as well as the beneficial effects of antioxidant therapies. PMID:26585821

  5. Optimized screening two-dimensional sequential time-of-flight MR angiographic runoff of the lower extremities

    International Nuclear Information System (INIS)

    This paper presents a relatively rapid and effective two-dimensional sequential time-of-flight MR angiographic technique by which high-quality angiographic images are obtained from the aortic bifurcation to the popliteal trifurcation vessels in two 12.5-minute acquisitions. The technique is performed with a 1.5-T whole- body imager (SP63, Siemens Medical Systems) running on A2.1 software. It employs a fast low-angle shot sequence, flow compensated in read and slice. We applied and compared variable TRs, TEs, flip angles, section thicknesses, and overlaps in five normal volunteers. Images were postprocessed with an on-line maximum-intensity projection program

  6. Association of serum testosterone with lipid abnormalities in patients with angiographically proven coronary artery disease

    Directory of Open Access Journals (Sweden)

    Chandima Madhu Wickramatilake

    2013-01-01

    Full Text Available Context: Low testosterone levels are associated with an atherogenic lipid profile and may contribute to the pathogenesis of atherosclerosis. Aims: Our study aimed to investigate the relationship between serum total testosterone (TT levels and lipid profile in angiographically confirmed coronary artery disease (CAD in men. Settings and Design: This is a case-control hospital-based study at Teaching Hospital, Karapitiya, Galle, Sri Lanka. Materials and Methods: Two hundred and six men, 103 with angiographically proven CAD and 103 healthy men as a control group were studied. The serum levels of TT and lipids were assessed. Statistical Analysis: Data were analyzed using Minitab software (version 15 for Windows. Results: The mean concentrations of lipid parameters of patients and controls were as follows: Serum total cholesterol (TCh, 5.9 ± 2.8 vs. 5.2 ± 1.6 mmol/l (P = 0.022, low-density lipoprotein cholesterol (LDL-Ch, 3.9 ± 1.2 vs. 3.1 ± 0.5 mmol/l (P = 0.001, high-density lipoprotein cholesterol (HDL-Ch, 1.1 ± 0.5 vs. 1.4 ± 0.6 mmol/l (P = 0.001, and TGs, 2.0 ± 1.0 vs. 1.5 ± 0.8 mmol/l (P = 0.001; lipid levels were significantly different between the two groups. The mean levels of TT in the patients and controls were 11.4 ± 2.7 vs. 18.1 ± 7.2 nmol/l (P = 0.001, significantly different. Among CAD patients, a significant positive association was found between testosterone and HDL-Ch (r = 0.623, P = 0.001, whereas a negative association was found with LDL-Ch (r = -0.579, P = 0.001. Conclusions: Low levels of TT in men with CAD that appear together with an atherogenic lipid milieu may be involved in the pathogenesis of CAD. The observed association between testosterone and HDL-Ch suggests a protective effect of the hormone.

  7. Clinical and Angiographic Characteristics of Myocardial Bridges: a Descriptive Report of 19 Cases and Follow-up Outcomes

    OpenAIRE

    Maria Raissi Dehkordi; Hakimeh Sadeghian; Saeed Sadeghian; Hamidreza Goodarzynejad; Alireza Amirzadegan; Sirus Darabian

    2007-01-01

    Background: Muscle fibers overlying the intramyocardial segment of an epicardial coronary artery are termed myocardial bridge (MB). The aim of this study was to analyze the mid-term outcome of MB and to examine its possible association with angiographic findings and concomitant cardiac pathologies such as hypertrophic cardiomyopathy (HCM). Methods: From a total of 3218 patients admitted for coronary angiography during 9 consecutive months, 28 (0.9%) were diagnosed with MBs with stenoses >=5...

  8. Hemodynamic assessment of partial mechanical circulatory support: data derived from computed tomography angiographic images and computational fluid dynamics

    OpenAIRE

    Karmonik, Christof; Partovi, Sasan; Rengier, Fabian; Meredig, Hagen; Farag, Mina Berty; Müller-Eschner, Matthias; Arif, Rawa; Popov, Aron-Frederik; Kauczor, Hans-Ulrich; Karck, Matthias; Ruhparwar, Arjang

    2015-01-01

    Partial mechanical circulatory support represents a new concept for the treatment of advanced heart failure. The Circulite Synergy Micro Pump®, where the inflow cannula is connected to the left atrium and the outflow cannula to the right subclavian artery, was one of the first devices to introduce this concept to the clinic. Using computational fluid dynamics (CFD) simulations, hemodynamics in the aortic tree was visualized and quantified from computed tomography angiographic (CTA) images in ...

  9. Association of human carboxypeptidase E exon5 gene polymorphisms with angiographical characteristics of coronary atherosclerosis in a Chinese population

    Institute of Scientific and Technical Information of China (English)

    Jie WANG; En-zhi JIA; Yun ZHANG; Zhi-jian YANG; Tie-bing ZHU; Lian-sheng WANG; Bo CHEN; Ke-jiang CAO; Jun HUANG; Wen-zhu MA

    2008-01-01

    Aim: To explore the association between 801C>T and 847C>T polymorphisms of the human carboxypeptidase E (CPE) gene exon5, which could cause hyperproinsulinemia, and the angiographical characteristics of coronary atherosclerosis. Methods: In total, 1044 consecutive patients who underwent coronary angiography for suspected or known coronary atherosclerosis were examined with respect to their genotypes, insulin, proinsulin level, and other risk factors of coronary atherosclerosis. The angiographical characteristics of coro-nary atherosclerosis (ie the severity of coronary heart disease) were defined by Gensini's score (GS) system. Results: The results showed that the genotype frequencies ofCC, CT, and TT at 801C>T locus were significantly different among the patients of the 4 groups who were classified by quartile values of GS (P=0.033). However, the frequency of the 847T allele was 0 for all the patients. The ordinal logistic regression analysis revealed that the increased risk of angiographical characteristics of coronary atherosclerosis were associated with CPE 801CT/TT variant genotypes [adjusted odds ratio (OR)=1.23, 95% confidence interval (CI) =0.93-1.63 for 801CT and adjusted OR=3.13, 95% CI=1.18-8.28 for 801TT] com-pared with the 801CC wild-type homozygotes. A stratification analysis showed that the effects of the CPE 801TT genotype were more evident among subgroups with relatively older (>=60 years) patients, males, and smokers. Furthermore, an analysis of covariance controlling age, sex, and body mass index indicated that differences of blood glucose, insulin, insulin resistance, and the proinsulin level between 801C>T genotype groups were not statistically significant. Conclusion: These findings indicate that the 801C>T polymorphism in the CPE exon5 gene may contribute to the angiographical characteristics of coronary atherosclerosis in the Chinese population.

  10. Incidence of visible and occult blood on laryngoscope blades and handles.

    Science.gov (United States)

    Phillips, R A; Monaghan, W P

    1997-06-01

    Anesthesia providers must take appropriate precautions to reduce the potential for transmission of infectious agents to the patients under their care. The devastating spread of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) over the past decade has resulted in the development of specific guidelines for the cleaning, disinfection, sterilization, and handling of medical equipment and instruments. Contamination of laryngoscope blades and handles with visible and occult blood frequently occurs during routine airway management. Several studies suggest procedures for cleaning, disinfection, sterilization, or handling of laryngoscope blades and handles are ineffective, or there may be poor compliance with the established protocols. The purpose of this study was to determine the incidence of visible and occult blood on laryngoscope blades and handles that were identified as ready for patient use. Sixty-five laryngoscope blades and handles identified as ready for patient use were observed for visible blood and tested for occult blood. A modified version of the three-stage phenolphthalein blood indicator test was employed to determine the presence of occult blood. None of the blades or handles observed had visible blood. Of the 65 blades tested for occult blood, 13 (20%) tested positive. Of the 65 handles tested for occult blood, 26 (40%) tested positive. More afternoon blades and handles tested positive for occult blood than morning blades and handles (P laryngoscope blades and handles have irregular surfaces with repositories for infectious material. PMID:9233093

  11. Angiographic Evaluation of Carotid Artery Grafting with Prefabricated Small-Diameter, Small-Intestinal Submucosa Grafts in Sheep

    International Nuclear Information System (INIS)

    The purpose of this study was to report the longitudinal angiographic evaluation of prefabricated lyophilized small-intestinal submucosa (SIS) grafts placed in ovine carotid arteries and to demonstrate a variety of complications that developed. A total of 24 grafts, 10 cm long and 6 mm in diameter, were placed surgically as interposition grafts. Graft patency at 1 week was evaluated by Doppler ultrasound, and angiography was used for follow-up at 1 month and at 3 to 4 months. A 90% patency rate was found at 1 week, 65% at 1 month, and 30% at 3 to 4 months. On the patent grafts, angiography demonstrated a variety of changes, such as anastomotic stenoses, graft diffuse dilations and dissections, and aneurysm formation. These findings have not been previously demonstrated angiographically by other investigators reporting results with small-diameter vessel grafts made from fresh small-intestinal submucosa (SIS). The complications found were partially related to the graft construction from four SIS layers. Detailed longitudinal angiographic study should become an essential part of any future evaluation of small-vessel SIS grafting.

  12. Data on the lipoprotein (a), coronary atherosclerotic burden and vulnerable plaque phenotype in angiographic obstructive coronary artery disease.

    Science.gov (United States)

    Niccoli, Giampaolo; Chin, Diana; Scalone, Giancarla; Panebianco, Mario; Abbolito, Sofia; Cosentino, Nicola; Jacoangeli, Francesca; Refaat, Hesham; Gallo, Giovanna; Salerno, Gerardo; Volpe, Massimo; Crea, Filippo; De Biase, Luciano

    2016-06-01

    Lipoprotein Lp(a) represents an independent risk factor for coronary artery disease (CAD). However, its association with CAD burden and lipid rich plaques prone to rupture in patients with acute coronary syndrome (ACS) still remains unknown. These data aim to investigate the association among serum Lipoprotein(a) (Lpa) levels, coronary atherosclerotic burden and features of culprit plaque in patients with ACS and obstructive CAD. For his reason, a total of 500 ACS patients were enrolled for the angiographic cohort and 51 ACS patients were enrolled for the optical coherence tomography (OCT) cohort. Angiographic CAD severity was assessed by Sullivan score and by Bogaty score including stenosis score and extent index, whereas OCT plaque features were evaluated at the site of the minimal lumen area and along the culprit segment. In the angiographic cohort, Lp(a) was a weak independent predictor of Sullivan score (p30 md/dl) compared to patients with lower Lp(a) levels (<30 md/dl) exhibited a higher prevalence of lipidic plaque at the site of the culprit stenosis (P=0.02), a wider lipid arc (p=0.003) and a higher prevalence of thin-cap fibroatheroma (p=0.004). PMID:27158659

  13. Central Flash Analysis of the 29 June 2015 Occultation

    Science.gov (United States)

    Person, Michael J.; Bosh, A. S.; Sickafoose, A. A.; Zuluaga, C. A.; Levine, S. E.; Pasachoff, J. M.; Babcock, B. A.; Dunham, E. W.; McLean, I.; Wolf, J.; Abe, F.; Becklin, E.; Bida, T. A.; Bright, L. P.; Brothers, T. C.; Christie, G.; Collins, P. L.; Durst, R. F.; Gilmore, A. C.; Hamilton, R.; Harris, H. C.; Johnson, C.; Kilmartin, P. M.; Kosiarek, M. R.; Leppik, K.; Logsdon, S. E.; Lucas, R.; Mathers, S.; Morley, C. J. K.; Natusch, T.; Nelson, P.; Ngan, H.; Pfueller, E.; Roeser, H.-P.; Sallum, S.; Savage, M.; Seeger, C. H.; Siu, H.; Stockdale, C.; Suzuki, D.; Thanathibodee, T.; Tilleman, T.; Tristram, P. J.; Van Cleeve, J.; Varughese, C.; Weisenbach, L. W.; Widen, E.; Wiedemann, M.

    2015-11-01

    After an extensive prediction effort, the 29 June 2015 occultation by Pluto was observed from both airborne (Stratospheric Observatory for Infrared Astronomy - SOFIA) and numerous ground-based telescopes (Bosh et al. - this meeting). Real-time prediction updates allowed placement of the SOFIA telescope with its four detectors deep within the central-flash region of the atmospheric occultation. Fortuitously, the Mount John University Observatory (Lake Tekapo, New Zealand) was also within the central-flash region (Pasachoff et al. - this meeting). This happenstance resulted in multiple central-flash detections in several colors from each facility allowing direct comparison of different areas of the central-flash evolute.Here we examine and discuss the central-flash signatures from the highest signal-to-noise light curves from each facility. The relative orientations and asymmetries in the central flashes allow us to use them to tightly constrain the lower atmospheric ellipticity and orientation of likely winds with respect to Pluto’s figure. The ratio of the two separate central flashes is also a strong constraint on the geometric solution for the full occultation data set, and the absolute height of the central flashes with respect to those expected for a clear isothermal atmosphere places constraints on haze densities and thermal gradients in Pluto’s lower atmosphere. We can also compare the central-flash signatures in several colors (similar to Sickafoose et. al - this meeting) to establish bounds on haze-particle sizes in the lower atmosphere.SOFIA is jointly operated by the Universities Space Research Association, Inc. (USRA), under NASA contract NAS2-97001, and the Deutsches SOFIA Institut (DSI) under DLR contract 50 OK 0901 to the University of Stuttgart. Support for this work was provided, in part, by NASA grants SSO NNX15AJ82G (Lowell Observatory), PA NNX10AB27G (MIT), and PA NNX12AJ29G (Williams College), as well as the National Research Foundation of

  14. Cerebellar arteries originating from the internal carotid artery: angiographic evaluation and embryologic explanations

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Young; Han, Moon Hee; Yu, In Gyu; Chang, Ki Hyun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Eui Jong [Kyunghee Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Dae Ho [Soonchunhyang Univ. College of Medicine, Asan(Korea, Republic of)

    1997-06-01

    To find and describe the cerebellar arteries arising from the internal carotid artery, explain them embryologically, and evaluate their clinical implication. To determine the point in the internal carotid artery from which the cereballar artery arose anomalously, consecutive angiographic studies performed in the last three years were reviewed. The distribution of such anomalous cerebellar arteries, the point in the internal carotid artery from which the anomalous vessels originated, and associated findings were analyzed. Five anomalous origins of cerebellar arteries arising arising directly from the internal carotid artery were found in five patients. Three anterior inferior cerebellar arteries (AICA) and one common trunk of an AICA and a posterior inferior cerebellar artery (PICA) were found to originate from the internal carotid artery at a point close to the origin of the primitive trigeminal artery. A PICA arose from an artery presenting a course similar to the proatlantal intersegmental artery. Intracranial aneurysms in two patients, Moyamoya disease in one, and facial arteriovenous malformation in one. In our series, AICAs supplied from the arteries considered to be persistent trigeminal artery variants were the most common type. A correlation between type of anomalous cerebellar artery and type of carotid-vertebrobasilar anastomosis may exist. Cerebellar arteries originating anomalously from the internal carotid artery seem to occur as a result of the persistence of carotid-vertebrobasilar anastomoses associated with incomplete fusion of the longitudinal neural arteries. An understanding of these anomalous cerebellar arteries may help prevent accidents during therapeutic embolization and surgical treatment, as well as misinterpretation.

  15. Surface evaluation of cardiac angiographic catheters after simulated use and reprocessing

    International Nuclear Information System (INIS)

    Reprocessing of single-use intravascular catheters is a common practice in public health services and hospitals. The determination of safe number of reprocessing cycles before the catheter integrity becomes compromised has been a priority issue. The present paper addresses the evaluating molecular and micro-structural integrity of reprocessed cardiac angiographic catheters. The Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy were carried out to elucidate morphological changes. The tensile test was performed on catheters to examine changes in bulk characteristics. In this work, samples of catheters were reprocessed until nine times and sterilized by hydrogen peroxide plasma. It was observed that the number of hydrogen-bonded carbonyls groups increased in 0.05 u.a. (p < 0.001) after each reprocessing cycle. The spectra indicated degradation products included acids, esters, alcohols, and small amounts of other products containing a carbonyl functional group. The micrographs revealed that only after the fourth reprocessing cycle the effect increased in the surface roughness was more pronounced. On the other hand, after each reprocessing cycle and as consequence of extensive aging of polyamide/polyurethane blends of the catheters surface, it was observed that the micro-fissures, micro-scratches and micro-pores increased in quantity and length. The mechanical test proved that the Young modulus increased in average 3.26 MPa (p = 0.0003) at increasing number of reprocessing cycles, also suggestive of crosslinking in this material.

  16. High-Resolution CT and Angiographic Evaluation of NexStent Wall Adaptation

    International Nuclear Information System (INIS)

    Carotid stenting is a minimally invasive treatment for extracranial carotid artery stenosis. Stent design may affect technical success and complications in a certain subgroup of patients. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which has a unique rolled sheet design. Forty-one patients had 42 carotid arteries treated with angioplasty and stenting for internal carotid artery stenosis. The mean patient age was 65 ± 10 years. All patients underwent high-resolution computed tomographic angiography after the stent implantation. Data analysis included pre- and postprocedural stenosis, procedure complications, plaque calcification, and stent apposition. We reviewed the angiographic and computed tomographic images for plaque coverage and stent expansion. All procedures were technically successful. Mean stenosis was reduced from 84 ± 8% before the procedure to 15.7 ± 7% after stenting. Two patients experienced transient ischemic attack; one patient had bradycardia and hypotension. Stent induced kinking was observed in one case. Good plaque coverage and proper overlapping of the rolled sheet was achieved in all cases. There was weak correlation between the residual stenosis and the amount of calcification. The stent provides adequate expansion and adaptation to the tapering anatomy of the bifurcation.

  17. Angiographic CT with intravenous contrast agent application for monitoring of intracranial flow diverting stents

    International Nuclear Information System (INIS)

    Intracranial flow diverting devices are increasingly used to treat cerebral aneurysms. A reliable, non-invasive follow-up modality would be desirable. Our aim was to compare intra-arterial digital subtraction angiography (ia DSA) to angiographic computed tomography with intravenous contrast agent application (iv ACT) in the visualisation of flow diverting devices and aneurysm lumina. Follow-up monitoring by iv ACT (n = 36) and ia DSA (n = 25) in 14 patients treated with flow diverting devices for intracranial aneurysms was evaluated retrospectively. Images were evaluated by two neuroradiologists in anonymous consensus reading regarding the device deployment, wall apposition, neck coverage of the aneurysm, opacification of the vessel and device lumen, as well as the degree of aneurysm occlusion. Corresponding ia DSA and iv ACT images were scored identically in all patients regarding the stent deployment, wall apposition and neck coverage, as well as the degree of aneurysm occlusion and patency status of the device and parent artery. Opacification of the parent vessel lumen and perfused parts of the aneurysm was considered slightly inferior for iv ACT in comparison with ia DSA (seven of 36 cases), without impact on diagnosis. We demonstrated the feasibility and diagnostic value of iv ACT in follow-up imaging of intracranial flow diverting devices. Due to its high spatial resolution and non-invasive character, this novel technique might become a valuable imaging modality in these patients. (orig.)

  18. Local organ dose conversion coefficients for angiographic examinations of coronary arteries

    Energy Technology Data Exchange (ETDEWEB)

    Schlattl, H [GSF-National Research Center for Environment and Health, Institute of Radiation Protection, Ingolstaedter Landstr. 1, 85764 Neuherberg (Germany); Zankl, M [GSF-National Research Center for Environment and Health, Institute of Radiation Protection, Ingolstaedter Landstr. 1, 85764 Neuherberg (Germany); Hausleiter, J [Klinik fuer Herz- und Kreislauferkrankungen, Deutsches Herzzentrum Muenchen, Klinik an der Technischen Universitaet Muenchen, Lazarettstr. 36, 80636 Munich (Germany); Hoeschen, C [GSF-National Research Center for Environment and Health, Institute of Radiation Protection, Ingolstaedter Landstr. 1, 85764 Neuherberg (Germany)

    2007-08-07

    New organ dose conversion coefficients for coronary angiographic interventions are presented, as well as dose distributions and resulting maximal local dose conversion coefficients in the relevant organs. For the Monte Carlo based simulations, voxel models of the human anatomy were employed which represent the average Caucasian adult man and woman as defined by the International Commission on Radiological Protection. In the 21 investigated projections, the mean organ dose conversion coefficients vary from a few 0.01 to 2 mGy(Gy cm{sup 2}){sup -1}, depending on the projections. However, especially in portions of the lungs and the active bone marrow, the conversion coefficients can locally amount up to 10 mGy(Gy cm{sup 2}){sup -1}, which is half the average conversion coefficient of the skin at the field entrance. In addition to the dose conversion coefficients, the dependence of the patient dose on the projection has been estimated. It could be shown that the patient doses are highest for left anterior oblique views with strong caudal or cranial orientation. Nevertheless, for a large range of image-intensifier positions no significant dose differences could be found.

  19. Vessel Size Estimation in Peripheral Artery Interventions: Are Angiographic Measurements Reliable?

    International Nuclear Information System (INIS)

    Purpose: To describe and evaluate a new technique for angiographic measurement of arterial diameters and to make a comparison with other common techniques. Material and Methods: The Angiometer has a radiopaque metal body with six cylindrical segments of varying diameter. Arterial diameter is estimated by visually relating the vessel to these segments. The measurements (method A) were compared: to measuring in relation to a ruler on the table-top by means of compasses (B), to an automated measurement technique (quantitative angiography) utilizing calibration to a catheter of known diameter (C), and to a computer-based distance measurement using the ruler on the table-top as reference (D). Twenty-five patients were studied. Each method was used twice by each of two independent observers. A phantom with four drilled holes, filled with contrast agent, was also studied. Results: The coefficient of variation was highest for method C and lowest for method A. Correlations between readings were highest for method A and lowest for method C. Mean diameter values were highest for method A and lowest for methods B and D. In the phantom experiments, sizes were overestimated by between 5% and 9% with method A, and underestimated by between 4% and 27% with the other methods. Conclusion: In terms of reproducibility and accuracy, the proposed method compares favorably with alternative methods

  20. Determination of optimal angiographic viewing angles: Basic principles and evaluation study

    International Nuclear Information System (INIS)

    Foreshortening of vessel segments in angiographic (biplane) projection images may cause misinterpretation of the extent and degree of coronary artery disease. The views in which the object of interest are visualized with minimum foreshortening are called optimal views. In this paper the authors present a complete approach to obtain such views with computer-assisted techniques. The object of interest is first visualized in two arbitrary views. Two landmarks of the object are manually defined in the two projection images. With complete information of the projection geometry, the vector representation of the object in the three-dimensional space is computed. This vector is perpendicular to a plane in which the views are called optimal. The user has one degree of freedom to define a set of optimal biplane views. The angle between the central beams of the imaging systems can be chosen freely. The computation of the orientation of the object and of corresponding optimal biplane views have been evaluated with a simple hardware phantom. The mean and the standard deviation of the overall errors in the calculation of the optimal angulation angles were 1.8 degree and 1.3 degree, respectively, when the user defined a rotation angle

  1. The role of Sesta-Mibi-SPECT in angiographically documented coronary heart disease

    International Nuclear Information System (INIS)

    131 patients were studied to compare the results of 99mTc-Mibi-SPECT with coronary angiography (CAG). 127 patients remained for final evaluation. A scar was falsely diagnosed in 17. 13 patients had a normal CAG and pathologic Sesta-Mibi-SPECT. 5 of them suffered from cardiomyopathy. 2 patients have had a myocarditis, at 2 others a PTCA was perfomred. 1 patient had a 20% LCA-stenosis and another one a left ventricular hypertrophy. Two times the reason for the pathologic Sesta-Mibi-SPECT could not be found. 1 patient had a normal Sesta-Mibi-SPECT despite of a pathologic CAG, angina pectoris and pathologic ECG. We got congruent results in 113 patients. 7 patients showed a left bundle branch block (LBBB), in 5 of them the Mibi-SPECT corresponded well with the CAG. 2 patients with dilated cardiomyopathy and no CHD showed an exercise induced ischemia in the anteroseptal wall. In patiens with angiographically documented CHD Sesta-Mibi-SPECT gives reliable diagnostic information concerning the myocardial perfusion. (orig./MG)

  2. X-ray region of interest imaging system for rapid-sequence angiography and fluoroscopy: The micro-angiographic fluoroscope

    Science.gov (United States)

    Wu, Ye

    Neuro-endovascular interventional diagnosis and treatment require high resolution x-ray imaging guidance of fluoroscopy and angiography. Our group has developed a small field of view, 5 frames per second, high-resolution micro-angiographic imager. This imager has demonstrated substantial high-resolution advantages for angiography over the conventional image intensifier. The work of this dissertation is to build a new micro-angiographic fluoroscope (MAF) to expand the capabilities of the micro-angiographic imager to include fluoroscopic imaging over a small field of view. The components of the MAF are all commercially available including CsI (T1) scintillator, fiber-optic taper, light image intensifier (LII), mirror, lens, and CCD camera. The critical component is the microchannel plate based LII with very high spatial resolution. The LII has a large range of gain that can be controlled easily by a 5V to 9V DC voltage. This property enables the MAF to be used for angiography with a low gain of the LII, and for fluoroscopy with a high gain of the LII. This design was justified by the quantum accounting diagram calculation. The preliminary experimental results from the test model MAF demonstrated the feasibility of this design. The improved prototype MAF model demonstrates high-resolution imaging for both fluoroscopy and angiography. The performance descriptors of the prototype MAF such as MTF, NPS, and DQE, were measured in both angiographic mode and fluoroscopic mode. For angiographic mode, at spatial frequencies of 4 and 10 lp/mm, the MTF for the MAF was 14% and 1.5% respectively, the DQE for the MAF was 12% and 1.2% respectively, while the DQE (0) was about 60%. For fluoroscopic mode, at spatial frequency of 4 lp/mm, the MTF for the MAF was 11%, and the DQE for the MAF was 9.5%. The image lag for the MAF in fluoroscopic mode at a rate of 30 fps was measured to be minimal. The allowable maximum entrance exposure rate was found to be related with the maximum LII

  3. Atmospheric stability index using radio occultation refractivity profiles

    Indian Academy of Sciences (India)

    D Jagadheesha; B Manikiam; Neerja Sharma; P K Pal

    2011-04-01

    A new stability index based on atmospheric refractivity at ∼500 hPa level and surface measurements of temperature, pressure and humidity is formulated. The new index named here as refractivity based lifted index (RLI) is designed to give similar results as traditionally used lifted index derived from radiosonde profiles of temperature, pressure and humidity. The formulation of the stability index and its comparison with the traditional temperature profile based lifted index (LI) is discussed. The index is tested on COSMIC radio occultation derived refractivity profiles over Indian region. The forecast potential of the new index for rainfall on 2° × 2° latitude–longitude spatial scale with lead time of 3–24 hours indicate that the refractivity based lifted index works better than the traditional temperature based lifted index for the Indian monsoon region. Decreasing values of RLI tend to give increasing rainfall probabilities.

  4. Clinical significance of occult hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    Miriam Romero; Antonio Madejón; Conrado Fernández-Rodríguez; Javier García-Samaniego

    2011-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is defined as the presence of HBV DNA in the liver (with or without detectable HBV DNA in serum) for individuals testing HBV surface antigen negative. Until recently, the clinical effect of OBI was unclear on the progression of liver disease; on the development of hepatocellular carcinoma; and on the risk for reactivation or transmission of HBV infection. Several studies suggest a high prevalence of OBI among patients with cryptogenic chronic liver disease, but its role in the progression to cirrhosis remains unclear. Although OBI has been well documented in human immunodeficiency virus (HIV)-positive patients, especially among those coinfected with hepatitis C virus, further studies are needed to determine its current clinical impact in HIV setting.

  5. A case of occult intrahepatic cholangiocarcinoma diagnosed by autopsy.

    Science.gov (United States)

    Oda, Eri; Hashimoto, Daisuke; Shiomi, Yuko; Ohnishi, Koji; Hayashi, Hiromitsu; Chikamoto, Akira; Takeya, Motohiro; Baba, Hideo

    2015-12-01

    Cancer of unknown primary is associated with unknown biology and dismal prognosis. The most common primary sites of cancer of unknown primary were usually the lungs in autopsy studies, and intrahepatic cholangiocarcinoma is rare. We describe the case of a 57-year-old male patient with systemic lymph node metastasis. Imaging examination failed to reveal primary cancer; however, immunostaining of cytokeratins 7, 19, and 20 of a metastatic axillary lymph node suggested a pancreaticobiliary cancer as a primary lesion. He died of liver abscess and sepsis, and then, autopsy indicated occult intrahepatic cholangiocarcinoma. We discuss the clinical course of this rare cholangiocarcinoma including the diagnostic procedure and also present a review of the English literature regarding patients with cancer of unknown primary. PMID:26943425

  6. Acute Zonal Occult Outer Retinopathy with Atypical Findings

    Directory of Open Access Journals (Sweden)

    Dimitrios Karagiannis

    2014-01-01

    Full Text Available Background. To report a case of acute zonal occult outer retinopathy (AZOOR with atypical electrophysiology findings. Case Presentation. A 23-year-old-female presented with visual acuity deterioration in her right eye accompanied by photopsia bilaterally. Corrected distance visual acuity at presentation was 20/50 in the right eye and 20/20 in the left eye. Fundus examination was unremarkable. Visual field (VF testing revealed a large scotoma. Pattern and full-field electroretinograms (PERG and ERG revealed macular involvement associated with generalized retinal dysfunction. Electrooculogram (EOG light rise and the Arden ratio were within normal limits bilaterally. The patient was diagnosed with AZOOR due to clinical findings, visual field defect, and ERG findings. Conclusion. This is a case of AZOOR with characteristic VF defects and clinical symptoms presenting with atypical EOG findings.

  7. Occult Orbitocranial Penetrating Pencil Injury in a Child

    Directory of Open Access Journals (Sweden)

    Faisal Al-Otaibi

    2012-01-01

    Full Text Available Transorbital slow-penetrating injury is an uncommon type of head injury that is seen more often in the pediatric age group. This type of injury can be occult, which is often associated with serious complications. We report on a 4-year-old female who presented with orbital swelling after an unwitnessed right orbital injury following a fall on her face at her school. Three days after injury, the presence of a foreign body was discovered on imaging study when she presented with orbital swelling and purulent discharges. She recovered well after surgical and medical management. This paper sheds light on the importance of high suspicion for the presence and early surgical management of a penetrating foreign body.

  8. Radiographically Occult and Subtle Fractures: A Pictorial Review

    International Nuclear Information System (INIS)

    Radiographically occult and subtle fractures are a diagnostic challenge. They may be divided into (1) high energy trauma fracture, (2) fatigue fracture from cyclical and sustained mechanical stress, and (3) insufficiency fracture occurring in weakened bone (e.g., in osteoporosis and post radiotherapy). Independently of the cause, the initial radiographic examination can be negative either because the findings seem normal or are too subtle. Early detection of these fractures is crucial to explain the patients symptoms and prevent further complications. Advanced imaging tools such as computed tomography, magnetic resonance imaging, and scintigraphy are highly valuable in this context. Our aim is to raise the awareness of radiologists and clinicians in these cases by presenting illustrative cases and a discussion of the relevant literature.

  9. Remote sensing of tropospheric turbulence using GPS radio occultation

    Science.gov (United States)

    Shume, Esayas; Ao, Chi

    2016-07-01

    Radio occultation (RO) measurements are sensitive to the small-scale irregularities in the atmosphere. In this study, we present a new technique to estimate tropospheric turbulence strength (namely, scintillation index) by analyzing RO amplitude fluctuations in impact parameter domain. GPS RO observations from the COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) satellites enabled us to calculate global maps of scintillation measures, revealing the seasonal, latitudinal, and longitudinal characteristics of the turbulent troposphere. Such information are both difficult and expensive to obtain especially over the oceans. To verify our approach, simulation experiments using the multiple phase screen (MPS) method were conducted. The results show that scintillation indices inferred from the MPS simulations are in good agreement with scintillation measures estimated from COSMIC observations.

  10. External radiation therapy for roentgenographically occult lung cancers

    International Nuclear Information System (INIS)

    From January 1982 to May 1991, the authors have treated 13 cases of a roentgenographically occult lung cancer by using a 4∼10 MV photon beam. All 13 patients were males whose ages ranged from 53 to 84 years (mean: 71.4 years) and each was a heavy cigarrette smoker. In each instance, a sputum cytologic study uncovered abnormal findings and bronchoscopy revealed a localized cancer. For radiotherapy, radiation doses ranged from 50∼70 Gy (mean: 64.0 Gy), and the radiation field ranged from 25.75 to 90 cm2 (mean: 43.2 cm2). During the follow-up period of 11 to 68 months (mean: 34.2 months), 2 patients died of the carcinoma, 1 still has the carcinoma, and 3 died of other causes. The 5-year survival rate was 62%. (author)

  11. Carcinogenesis of gallbladder mucosa with occult pancreatobiliary reflux

    International Nuclear Information System (INIS)

    Characteristics of gallbladder cancer (GC) with occult pancreatobiliary reflux (OPBR) were retrospectively examined with images by US (ultrasonography), endoscopic US (EUS), ERCP (endoscopic retrograde cholangiopancreatography) and multi-row CT, and with pathological specimens of the mucosa to consider its carcinogenesis. Subjects were 51-77 years old, 7 female patients with GC in whom OPBR was suggested mainly by mucosal hypertrophy in those images. Pathological observation was performed on specimens stained by HE and Ki-67 (for detecting cell proliferation). Imaging and pathological findings of the mucosa in the present GC were found analogous to known characteristics of GC with abnormal pancreatbiliary confluence, suggesting a similar carcinogenetic process to each other, where biliary phospholipids (PL) were degraded to toxic lyso-PL and free fatty acids. The subject with OPBR could thus be classified in the high risk group. More cases in number were thought necessary to define the surgical treatment, its timing and procedure in GC. (R.T.)

  12. Occult pulmonary embolism: a common occurrence in deep venous thrombosis

    International Nuclear Information System (INIS)

    Ventilation-perfusion scans were used in a prospective study to determine the prevalence of occult pulmonary embolus in proven deep venous thrombosis. Fifty-eight patients without symptoms of pulmonary embolism, but with venographically proven deep venous thrombosis, were subjected to chest radiographs, /sup 99m/Tc macroaggregated-albumin perfusion scans, and 133Xe ventilation scans. Of the 49 patients with deep venous thrombosis proximal to the calf veins, 17 (35%) had high-probability scans. Of all 58 patients, only 12 (21%) had normal scans. When the study population was compared with a group of 430 patients described in reports of pulmonary perfusion in asymptomatic persons, a significantly higher percentage of high-probability scans was found in the study population with deep venous thrombosis. Baseline ventilation-perfusion lung scanning is valuable for patients with proven above-knee deep venous thrombosis

  13. Detection of occult colovesical fistula by the Bourne test.

    Science.gov (United States)

    Amendola, M A; Agha, F P; Dent, T L; Amendola, B E; Shirazi, K K

    1984-04-01

    The value of different diagnostic tests in the detection of colovesical fistulas was studied in 28 surgically proven cases seen during the last 10 years at the University of Michigan, Ann Arbor. Etiologies were diverticulitis (19), Crohn disease (three), postradiation therapy (four), previous trauma (one), and bladder carcinoma (one). The fistulas were demonstrated by barium enema in 10 of 20 patients and by cystography in eight of 26. Cystoscopy was diagnostic in 11 of 25 patients and sigmoidoscopy in four of 24. Methylene blue test was positive in five of six patients, and in one patient given a charcoal enema the material appeared in the urine. The Bourne test, consisting of radiography of the centrifuged urine samples obtained immediately after a nondiagnostic barium enema, was positive in nine of 10 patients. In seven of these 10 patients, the Bourne test was the only positive evidence of an otherwise occult colovesical fistula later proven at surgery. PMID:6608228

  14. A rare case of occult splenic rupture after left pneumonectomy.

    Science.gov (United States)

    Acharya, Metesh N; George, Robert S; Loubani, Mahmoud

    2016-01-01

    Cardiopulmonary resuscitation (CPR) techniques are now well-established and play a crucial role in improving survival in cardiac arrest. Recognized complications associated with CPR include injury to the upper abdominal viscera, including the liver, stomach and spleen. We present a rare case of occult splenic rupture following cardiac arrest in a 63-year-old male immediately after left pneumonectomy. We discuss potential mechanisms predisposing the spleen to injury in this case, and highlight the difficulty of promptly identifying such a traumatic injury within the confines of a cardiac arrest scenario. Clinicians should be aware that anatomical changes following thoracic surgery may render the intra-abdominal viscera at increased risk of injury following CPR. PMID:27190201

  15. Pediatric chin injury: occult condylar fractures of the mandible.

    Science.gov (United States)

    Lee, C Y; McCullom, C; Blaustein, D I

    1991-06-01

    The diagnosis of occult mandibular condylar fractures in children is often missed or delayed on initial examination when children present with a laceration to the chin. A clue to the diagnosis of this type of skeletal injury to the mandible is the knowledge of a commonly occurring pattern of injury associated with chin trauma. Chin laceration, fracture of the parasymphyseal region near the chin, and fracture of the condyles are often concomitant injuries of the mandible. This article reviews three case reports of children who sustained a chin laceration, fracture in the region near the chin, and fracture to the mandibular condyles secondary to chin trauma that were not initially diagnosed on clinical examination. PMID:1876507

  16. Sensitivity of GPS occultation to the stratopause height

    DEFF Research Database (Denmark)

    Schrøder, Thomas Morville; Ao, Chi; de la Torre Juárez, Manuel

    2007-01-01

    We scrutinize temperature profiles collected with radio occultation measurement for an imprint of the stratopause. In the retrieval step that integrates bending angle data to atmospheric refractivity, the falloff toward infinite altitude is constrained in a boundary condition with statistical...... optimization or extrapolation. We point to the coherence between temperature and density scale height as advocator for a fitting procedure that exploits data down to the stratopause. Data below have higher signal-to-noise ratio, but fitting them in costs additional parameters for the shifted sign in scale...... height gradient. On the basis of noise free simulation using a climatology covering all latitudes, seasons, and hours and on the basis of validation against data collected with weather balloons, laser imaging, and limb sounding, we find that adaptation to the fluctuating stratopause is crucial...

  17. Between occultism and drama. Henrik Ibsen and Aleister Crowley

    Directory of Open Access Journals (Sweden)

    Giuliano D' Amico

    2015-02-01

    Full Text Available The article investigates the references to the works of Henrik Ibsen that the writer and occultist Aleister Crowley scattered in his writings around the turn of the 20th century, in the early phase of his career as a writer and occultist. Crowley’s reading of Ibsen has a marked a socio-political bent, especially in his interpretation of the work of the Norwegian playwright as an act of rebellion against the bourgeois (and for Crowley, Victorian system of values. Also, such view is enriched by a spiritual and individualistic interpretation of Ibsen as an “Artist”, i.e., in the light of Crowley’s occult doctrine, Thelema, of an individual who has found his own “Will” and can inspire others to do so. Such social and spiritual interpretations of Ibsen on Crowley’s part found their literary realization in his one-act play The Mother’s Tragedy (1899. The article claims that Crowley’s reading of Ibsen can give some new insight in the mechanisms of reception of the Norwegian playwright, by opening up for a reading of some of his plays within an occult discourse. Also, it is an occasion to treat Crowley – a figure that was constantly present in the European cultural and literary life of the last decade of the 19th century and of the first five decades of the 20th – with a different attitude than the irony and disdain to which he is often exposed.

  18. Chariklo's size, shape and orientation from stellar occultations

    Science.gov (United States)

    Bérard, Diane; Sicardy, Bruno; Assafin, Marcelo; Braga-Ribas, Felipe; Camargo, Julio; Vieira Martins, Roberto; Duffard, Rene; Ortiz, Jose Luis; Snodgrass, Colin; Jehin, Emmanuel; Pollock, Joe; Colas, François; Dauvergne, Jean Luc; Lecacheux, Jean; Maquet, Lucie; Sickafoose, Amanda A.; Bath, Karl Ludwig; Beisker, Wolfgang; Leiva, Rodrigo

    2015-11-01

    Chariklo is the largest Centaur object known to date, and it is surrounded by dense and narrow rings (Braga-Ribas et al. Nature 508, 72, 2014). The size, shape and orientation of the central body are important parameters to better understand the dynamics of the rings.In that context, we have analyzed three stellar occultations by Chariklo and its main ring observed on June 3, 2013, April 29, 2014 and June 28, 2014. Elliptical limb fitting to Chariklo’s main body occultation chords has been performed, where we denote a (resp. b) the semi-major (resp. semi-minor) axis of the limb. Preliminary results indicate that Chariklo’s limb is elliptical with axes ratio b/a~0.89. We obtain a~133 km and b~119 km, providing an equivalent radius of Requiv=√(ab)~126 km. The rms dispersion of the fit, about 4 km, is compatible with local topographic features on a small icy body. For comparison, an equivalent radius of Requiv= 119±5 km, based on thermal data, is given by Fornasier et al, AA 518, L11, 2014, while Duffard et al. AA 568, A79, 2014 estimate a= 122 km and b= 117 km.Our results are obtained under the simplifying assumption that the main ring is circular and that its center coincides with that of Chariklo. Caveats and error bars will be discussed, and dynamical implications will be presented. In particular, rough estimations of the ring apsidal precession rates will be given, as well as constraints on Chariklo's density.

  19. Magellan radio occultation measurements of atmospheric waves on Venus

    Science.gov (United States)

    Hinson, David P.; Jenkins, J. M.

    1995-01-01

    Radio occultation experiments were conducted at Venus on three consecutive orbits of the Magellan spacecraft in October 1991. Each occultation occurred over the same topography (67 deg N, 127 deg E) and at the same local time (22 hr 5 min), but the data are sensitive to zonal variations because the atmosphere rotates significantly during one orbit. Through comparisons between observations and predictions of standard wave theory, we have demonstrated that small-scale oscillations in retrieved temperature profiles as well as scintillations in received signal intensity are caused by a spectrum of vertically propagating internal gravity waves. There is a strong similarity between the intensity scintillations observed here and previous measurements, which pertain to a wide range of locations and experiment dates. This implies that the same basic phenomenon underlies all the observations and hence that gravity waves are a persistent, global feature of Venus' atmosphere. We obtained a fairly complete characterization of a gravity wave that appears above the middle cloud in temperature measurements on all three orbits. The amplitude and vertical wavelength are about 4 K and 2.5 km respectively, at 65 km. A model for radiative damping implies that the wave intrinsic frequency is approximately 2 x 10(exp 4) rad/sec, the corresponding ratio between horizontal and vertical wavelengths is approximately 100. The wave is nearly stationary relative to the surface or the Sun. Radiative attenuation limits the wave amplitude at altitudes above approximately 65 km, leading to wave drag on the mean zonal winds of about +0.4 m/sec per day (eastward). The sign, magnitude, and location of this forcing suggest a possible role in explaining the decrease with height in the zonal wind speed that is believed to occur above the cloud tops. Temperature oscillations with larger vertical wavelengths (5-10 km) were also observed on all three orbits, but we are able unable to interpret these

  20. Pluto's Atmosphere from the July 2010 Stellar Occultation

    Science.gov (United States)

    Person, Michael J.; Elliot, J. L.; Bosh, A. S.; Gulbis, A. A. S.; Jensen-Clem, R.; Lockhart, M. F.; Zangari, A. M.; Zuluaga, C. A.; Levine, S. E.; Pasachoff, J. M.; Souza, S. P.; Lu, M.; Malamut, C.; Rojo, P.; Bailyn, C. D.; MacDonald, R. K. D.; Ivarsen, K. M.; Reichart, D. E.; LaCluyze, A. P.; Nysewander, M. C.; Haislip, J. B.

    2010-10-01

    We have observed the 4 July 2010 stellar occultation by Pluto as part of our program of monitoring Pluto's atmospheric changes over the last decade. Successful observations were obtained from three sites: Cerro Calan and Cerro Tololo, Chile, as well as the HESS-project site (High Energy Stereoscopic System) in southwestern Namibia. Successful telescope apertures ranged from 0.45 m to 1.0 m and resulted in seven occultation light curves for the event from among the three sites. Simultaneous analysis of the seven light curves indicates that Pluto's atmosphere continues to be stable, as the calculated atmospheric radii are consistent with those detected in 2006 (Elliot et al., AJ 134, 1, 2007) and 2007 (Person et al., AJ 136, 1510, 2008), continuing the stability that followed the large pressure increase detected between 1988 (Millis et al., Icarus 105, 282, 1993) and 2002 (Elliot et al., Nature 424, 165, 2003). We will present the overall astrometric solution as well as current profiles for Pluto's upper atmospheric temperature and pressure obtained from inversion of the light curves (Elliot, Person, and Qu, AJ 126, 1041, 2003). This work was supported, in part, by grants NNX10AB27G to MIT, NNX08AO50G to Williams College, and NNH08AI17I to the USNO from NASA's Planetary Astronomy Division. The 0.75-m ATOM (Automatic Telescope for Optical Monitoring) light curve was obtained with the generous assistance of the HESS-project staff, arranged by Stefan Wagner and Marcus Hauser of the University of Heidelberg. The 0.45-m Goto telescope at Cerro Calán National Astronomical Observatory, Universidad de Chile, was donated by the Government of Japan. PROMPT (Panchromatic Robotic Optical Monitoring and Polarimetry Telescopes) observations at Cerro Tololo were made possible by the Robert Martin Ayers Science Fund. Student participation was supported in part by NSF's REU program and NASA's Massachusetts Space Grant.

  1. Ultrasonographic features of vascular closure devices: initial and 6 month followup results

    International Nuclear Information System (INIS)

    This study aimed to evaluate the ultrasonographic findings for various types of vascular closure devices (VCDs) immediately after the angiographic procedure and at 6-month follow-up. We included 18 VCDs including Angio-Seal (n=4), FemoSeal (n=8), ExoSeal (n=3), Perclose (n=2), and StarClose (n=1) in this study. Four patients were implanted with 2 VCDs at the each side of bilateral femoral arteries, while the remaining 8 patients were inserted 1 VCD at the right femoral artery. Ultrasonography was performed within 10 days and at approximately 6 months after the angiographic procedure. Ultrasonographic morphology of the attached VCD and its relationship with the arterial wall were analyzed. Initial ultrasonography revealed the attached VCD as the relevant unique structure with successful deployment and hemostasis. Follow-up ultrasonography demonstrated partial absorption of hemostatic materials in cases of Angio-Seal (n=3), FemoSeal (n=5), and ExoSeal (n=3), changes in the soft tissue surrounding the femoral artery in case of Angio-Seal (n=1), arterial intimal hyperplasia in cases of FemoSeal (n=3), and no gross changes as compared with the initial ultrasonographic findings in cases of Perclose (n=2) and StarClose (n=1). Initial ultrasonographic evaluation reflected the unique structure of each VCD, with most of them being easily distinguishable. Follow-up ultrasonography revealed various changes in the affected vessels.

  2. Ultrasonographic features of vascular closure devices: initial and 6 month followup results

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Hye Jung; Jeong, Hae Woong; Park, Jin Young; Kim, Sung Tae; Seo, Jung Hwa; Lee, Sun Joo; Park, Young Mi [Inje University Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Jin, Sung Chul [Dept. of Neurosurgery, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2014-12-15

    This study aimed to evaluate the ultrasonographic findings for various types of vascular closure devices (VCDs) immediately after the angiographic procedure and at 6-month follow-up. We included 18 VCDs including Angio-Seal (n=4), FemoSeal (n=8), ExoSeal (n=3), Perclose (n=2), and StarClose (n=1) in this study. Four patients were implanted with 2 VCDs at the each side of bilateral femoral arteries, while the remaining 8 patients were inserted 1 VCD at the right femoral artery. Ultrasonography was performed within 10 days and at approximately 6 months after the angiographic procedure. Ultrasonographic morphology of the attached VCD and its relationship with the arterial wall were analyzed. Initial ultrasonography revealed the attached VCD as the relevant unique structure with successful deployment and hemostasis. Follow-up ultrasonography demonstrated partial absorption of hemostatic materials in cases of Angio-Seal (n=3), FemoSeal (n=5), and ExoSeal (n=3), changes in the soft tissue surrounding the femoral artery in case of Angio-Seal (n=1), arterial intimal hyperplasia in cases of FemoSeal (n=3), and no gross changes as compared with the initial ultrasonographic findings in cases of Perclose (n=2) and StarClose (n=1). Initial ultrasonographic evaluation reflected the unique structure of each VCD, with most of them being easily distinguishable. Follow-up ultrasonography revealed various changes in the affected vessels.

  3. Plant vascular development

    NARCIS (Netherlands)

    Rybel, De Bert; Mähönen, Ari Pekka; Helariutta, Yrjö; Weijers, Dolf

    2016-01-01

    Vascular tissues in plants are crucial to provide physical support and to transport water, sugars and hormones and other small signalling molecules throughout the plant. Recent genetic and molecular studies have identified interconnections among some of the major signalling networks that regulate

  4. Renal posttransplant's vascular complications

    Directory of Open Access Journals (Sweden)

    Bašić Dragoslav

    2003-01-01

    Full Text Available INTRODUCTION Despite high graft and recipient survival figures worldwide today, a variety of technical complications can threaten the transplant in the postoperative period. Vascular complications are commonly related to technical problems in establishing vascular continuity or to damage that occurs during donor nephrectomy or preservation [13]. AIM The aim of the presenting study is to evaluate counts and rates of vascular complications after renal transplantation and to compare the outcome by donor type. MATERIAL AND METHODS A total of 463 kidneys (319 from living related donor LD and 144 from cadaveric donor - CD were transplanted during the period between June 1975 and December 1998 at the Urology & Nephrology Institute of Clinical Centre of Serbia in Belgrade. Average recipients' age was 33.7 years (15-54 in LD group and 39.8 (19-62 in CD group. Retrospectively, we analyzed medical records of all recipients. Statistical analysis is estimated using Hi-squared test and Fischer's test of exact probability. RESULTS Major vascular complications including vascular anastomosis thrombosis, internal iliac artery stenosis, internal iliac artery rupture obliterant vasculitis and external iliac vein rupture were analyzed. In 25 recipients (5.4% some of major vascular complications were detected. Among these cases, 22 of them were from CD group vs. three from LD group. Relative rate of these complications was higher in CD group vs. LD group (p<0.0001. Among these complications dominant one was vascular anastomosis thrombosis which occurred in 18 recipients (17 from CD vs. one from LD. Of these recipients 16 from CD lost the graft, while the rest of two (one from each group had lethal outcome. DISCUSSION Thrombosis of renal allograft vascular anastomosis site is the most severe complication following renal transplantation. In the literature, renal allograft thrombosis is reported with different incidence rates, from 0.5-4% [14, 15, 16]. Data from the

  5. Observations of Hot-Jupiter occultations combining Spitzer and Kepler photometry

    Directory of Open Access Journals (Sweden)

    Knutson H.

    2011-02-01

    Full Text Available We present the status of an ongoing program which aim at measuring occultations by their parent stars of transiting hot giant exoplanets discovered recently by Kepler. The observations are obtained in the near infrared with WarmSpitzer Space Telescope and at optical wavelengths by combining more than a year of Kepler photometry. The investigation consists of measuring the mid-occultation times and the relative occultation depths in each band-passes. Our measurements of occultations depths in the Kepler bandpass is turned into the determination of the optical geometric albedo Ag in this wavelength domain. The brightness temperatures of these planets are deduced from the infrared observations. We combine the optical and near infrared planetary emergent fluxes to obtain broad band emergent spectra of individual planet. We finally compare these spectra to hot Jupiter atmospheric models in order broadly distinguishing these atmospheres between different classes of models.

  6. Occult gastrointestinal bleeding due to a Dieulafoy lesion in the terminal ileum

    NARCIS (Netherlands)

    Wegdam, J.A.; Hofker, H.S.; Dijkstra, G; Stolk, M.F.; Jacobs, M.A.; Suurmeijer, A.J.H.

    2006-01-01

    A 50-year-old man awaiting liver transplantation for primary sclerosing cholangitis developed iron-deficiency anaemia. Repeated occult gastrointestinal bleeding led to an increasing need for blood transfusions. After multiple oesophagogastroduodenoscopies and colonoscopies, videocapsule endoscopy fi

  7. Development and Performance of the PHOT (Portable High-Speed Occultation Telescope) Systems

    CERN Document Server

    Young, E F; Olkin, C B; Shoemaker, K; French, R G; Regester, J; Buie, M W

    2011-01-01

    The PHOT (Portable High-Speed Occultation Telescope) systems were developed for the specific purpose of observing stellar occultations by solar system objects. Stellar occultations have unique observing constraints: they may only be observable from certain parts of the globe; they often require a rapid observing cadence; and they require accurate timestamp information for each exposure. The PHOT systems consist of 14" telescopes, CCD cameras, camera mounting plates, GPS-based time standards, and data acquisition computers. The PHOT systems are similar in principle to the POETS systems (Portable Occultation, Eclipse and Transit Systems, described by Souza et al. 2006 and reported on by Gulbis et al. 2008), with the main differences being (a) different CCD/Cameras with slightly different specifications and (b) a stand-alone custom-built time standard used by PHOT, whereas POETS uses a commercial time-standard that is controlled from a computer. Since 2005, PHOT systems have been deployed on over two dozen occas...

  8. Occult hepatitis C virus infection is more common than hepatitis B infection in maintenance hemodialysis patients

    Institute of Scientific and Technical Information of China (English)

    Pankaj Jain; Sandeep Nijhawan

    2008-01-01

    Patients of end stage renal disease on maintenance hemodialysis were enrolled to study the prevalence of occult and dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and non-occult hepatitis B and C virus infection. One hundred and two patients were enrolled. Thirty patients had HCV infection, three of them were positive in anti-HCV. So, 27 (90%) of HCVpositive patients had occult HCV infection. Eleven (11%)patients had HBV infection. Five patients were positive in anti-HBc or HBV-DNA, but negative in HBsAg (occult HBV infection). Three (3%) patients had dual HBV and HCV infection. None of the patients showed changes in viral markers during the follow-up of 8 mo on average (1-12 mo).

  9. Fabrication and Measurement of Precision Structures for External Occulter Optical Edges Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project proposes to develop an occulter optical edge and optical edge measurement verification system suitable for astrophysics missions including JWST and the...

  10. Vascular manifestations of Behcet's disease

    Directory of Open Access Journals (Sweden)

    Regina Georgiyeva Goloeva

    2010-04-01

    Conclusion. Vascular disorders in BD were diagnosed in one fourth of the patients, mainly in young male patients. Severe thromboses with the development of chronic venous insignificance, Budd-Chiari syndrome, pulmonary and iliac artery aneurysms, and arterial thromboses were observed in male patients only. Vascular events were associated with erythema nodosum and epididymitis; in these concomitances, the vascular risk was substantially increased. Vascular death rates were 2,2%.

  11. Evidence that Pluto's atmosphere does not collapse from occultations including the 2013 May 04 event

    OpenAIRE

    Olkin, C. B.; Young, L. A.; Borncamp, D.; Pickles, A; Sicardy, B.; Assafin, M.; Bianco, F. B.; Buie, M. W.; Oliveira, A. Dias de; Gillon, Michaël; French, R. G.; Ramos Gomes, A.; Jehin, Emmanuel; Morales, N.; Opitom, Cyrielle

    2015-01-01

    Combining stellar occultation observations probing Pluto's atmosphere from 1988 to 2013, and models of energy balance between Pluto's surface and atmosphere, we find the preferred models are consistent with Pluto retaining a collisional atmosphere throughout its 248-year orbit. The occultation results show an increasing atmospheric pressure with time in the current epoch, a trend present only in models with a high thermal inertia and a permanent N2 ice cap at Pluto's north rotational pole. ...

  12. Detection of occult hepatitis B virus among chronic hepatitis C patients

    Directory of Open Access Journals (Sweden)

    Ola Abd El Kader Mahmoud

    2016-06-01

    Results: Fifty-eight percent of the study group were positive for anti-HBc. Meanwhile, only 18 cases (18% were positive for the polymerase gene by nested PCR and were considered as occult HBV. Among these 18 polymerase gene positive patients (occult HBV anti-HBc was detected among 9 (50% of cases. Different gene profiles were noticed among the 18 polymerase gene positive patients.

  13. Occult Hepatitis C Virus Infection in Haemodialysis Unit: A Single-center Experience

    Directory of Open Access Journals (Sweden)

    Abdel Hamid A. Serwah1, Waleed S. Mohamed1, Mohamed Serwah1, Awateif Edreis2, Ahmad El Zaydi3

    2014-07-01

    Full Text Available Background & Aims: Detection of hepatitis C virus RNA in peripheral blood mononuclear cells (PBMC and/or hepatocytes in the absence of HCV RNA in serum, designated as ‘occult HCV infection’, has been a matter of controversy in the recent years. Occult hepatitis C virus (HCV infection has not been investigated in haemodialysis patients. We investigated for the first time the prevalence of occult HCV infection in large cohorts of chronic hemodialysis (CHD patients in a single heamodialysis center at Al-Taif, KSA. Methods: We enrolled 84 CHD patients, whose sera are negative for HCV markers. HCV RNA was tested in PBMC using a sensitive commercial real time assay. In this study, real-time PCR was used to test for the presence of genomic HCV-RNA in peripheral blood mononuclear cells of all of these patients. For comparison, 20 patients on HD with evidence of chronic hepatitis C virus infection were included as a control group. Results: In CHD patients, occult HCV infection, determined by the presence of genomic HCV-RNA in peripheral blood mononuclear cells (PBMNCs, was found in 13.4 % of the patients; 83 % of these patients had ongoing HCV replication, indicated by the presence of HCV-RNA. Patients with occult HCV infection had spent a significantly longer time on heamodialysis and had significantly higher mean alanine aminotransferase levels during the 3 months before study entry. Compared to CHCV patients, those with occult HCV have less elevated bilirubin, AST and ALT. Conclusions: The prevalence of occult HCV infection was moderate in our CHD patients, and it did not appear to be clinically relevant. Further studies in other geographic populations with high HCV endemicity are required to clarify the significance of occult HCV infection in these patient groups. Abbreviations HCV, Hepatitis C Virus ; antibody against HCV; PBMC, peripheral blood mononuclear cells; rRT-PCR, real time reverse transcriptase polymerase chain reaction; CHD, chronic

  14. Correlation of Telomere Length and Telomerase Activity with Occult Ovarian Insufficiency

    OpenAIRE

    Butts, Samantha; Riethman, Harold; Ratcliffe, Sarah; Shaunik, Alka; Coutifaris, Christos; Barnhart, Kurt

    2009-01-01

    Background: Occult ovarian insufficiency is associated with infertility, impaired response to ovarian stimulation, and reduced live birth rates in women treated with assisted reproductive technologies. Although a decline in ovarian follicle number is expected with age, the proximate causes of occult ovarian insufficiency in young women remain poorly understood. Abnormalities in telomere length and telomerase activity in human granulosa cells may serve as molecular markers for this condition.

  15. Detection of an occult transclival cerebrospinal fluid fistula by CT and MRI

    International Nuclear Information System (INIS)

    We describe an unusual occult transclival cerebrospinal fluid (CSF) fistula to the sphenoid sinus demonstrated by MRI. CT was performed because of a posterior cerebral infarct caused by cardiac arrhythmia. Axial sections showed fluid in the sphenoid sinus. High-resolution scans revealed a bony defect 3 mm in diameter of the posterior wall of the sphenoid sinus, and MRI showed a transclival CSF fistula. This occult lesion was confirmed by surgery and duraplasty was successfully performed via an endonasal approach. (orig.)

  16. Occult Hepatitis B Virus Infection in a Previously Vaccinated Injection Drug User

    Science.gov (United States)

    Powell, Eleanor A.; Razeghi, Sanam; Zucker, Stephen; Blackard, Jason T.

    2016-01-01

    Introduction: Occult hepatitis B virus (HBV) is defined by the presence of HBV DNA in patient sera in the absence of HBsAg. Occult HBV has been associated with hepatocellular carcinoma, reactivation during immune suppression, and transmission to others. While the hepatitis B vaccine is very effective at preventing chronic HBV infection, recent studies indicate it is less effective at preventing occult HBV following infant vaccination. No studies, however, have examined the efficacy of adult HBV vaccination at preventing occult HBV. Here, we present the first report of occult HBV following adult vaccination. Case Presentation: A 21-year old Caucasian female presented with tricuspid valve endocarditis secondary to methicillin-susceptible Staphylococcus aureus with non-ischemic cardiomyopathy. She reported active use of intravenous drugs. Her liver enzymes were elevated (ALT = 1873 IU/mL; AST = 4518 IU/mL), and she was found to have HCV and occult HBV. HBV viral loads ranged from 4608 - 8364 copies IU/mL during hospitalization. The patient’s HBV was sequenced and found to be genotype D3 without any known diagnostic escape mutations. Immune complexes that may have prevented HBsAg detection were not observed. Conclusions: HBV vaccination in infancy is effective at preventing chronic HBV infection but is less effective at preventing occult HBV infection. Similar studies examining the efficacy of adult HBV vaccination in preventing occult HBV have not been performed. This case highlights the importance of carefully determining the HBV status of high-risk individuals, as vaccination history and the presence of anti-HBs may not be adequate to rule out HBV infection, even in the absence of HBsAg.

  17. Solid and liquid occult precipitation in the headwater regions of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Fišák, Jaroslav; Tesař, Miroslav

    Bergen: Universitas Bergensis, 2005, ---. [International conference on Headwater Control VI: Hydrology, Ecology and Water Resources. Bergen (NO), 20.06.2005-23.06.2005] R&D Projects: GA AV ČR(CZ) IAA3042301; GA ČR(CZ) GA205/04/0060 Institutional research plan: CEZ:AV0Z30420517 Keywords : Occult precipitation * frequence of occurence and duration * solid and liquid occult precipitation * cloud and fog water deposition * rime * chemistry Subject RIV: DG - Athmosphere Sciences, Meteorology

  18. The importancy of finger extension test in the diagnosis of occult wrist ganglion

    OpenAIRE

    Kayalar, Murat; Vatansever, Aziz; Bal, Emin; Toros, Tulgar; Ozaksar, Kemal; Ada, Sait

    2004-01-01

    Objectives: The aim of this study was to evaluate the accuracy of diagnostic tools in comparison with surgical results of occult ganglion cyst of the wrist, which is one of the causes of chronic wrist pain. Methods: Twenty-five patients (4 males, 21 females; mean age 29 years; range 16 to 46 years) underwent surgery with an initial diagnosis of occult ganglion following unsuccessful conservative treatment. The mean symptom duration was 29 months (range 3 months to 10 years). Diagnosis was ...

  19. Infectivity of blood products from donors with occult hepatitis B virus infection

    DEFF Research Database (Denmark)

    Allain, Jean-Pierre; Mihaljevic, Ivanka; Gonzalez-Fraile, Maria Isabel;

    2013-01-01

    Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors.......Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors....

  20. Cerebral hemodynamics and metabolism in adult moyamoya disease. Comparison of angiographic collateral circulation

    International Nuclear Information System (INIS)

    The extent of the hemodynamic and metabolic impairments in adult patients with moyamoya disease is still controversial. The aim of the present study was to evaluate the hemodynamic and metabolic status in relation to the development of basal moyamoya vessels (BMVs). The cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF), and cerebral blood volume (CBV) were measured using PET in ten patients with ischemic adult moyamoya disease (mean age, 36.6 years) and six age-matched normal controls (mean age, 33.3 years). The cerebrovascular reserve (CVR) after acetazolamide (ACZ) loading was also estimated using iodine-123 N-isopropyl-p-iodo amphetamine single photon emission computed tomography (123I-IMP SPECT). Based on the angiographic findings, eleven cerebral hemispheres with well-developed BMV (extensive BMV hemispheres) and nine cerebral hemispheres with diminished BMV (diminished BMV hemispheres) were identified. The main routes of collateral circulation in extensive BMV hemispheres were BMVs and leptomeningeal anastomoses. On the other hand, in diminished BMV hemispheres, transdural anastomosis was predominant, and leptomeningeal anastomoses were less developed. In cortices distal to the occluded internal carotid artery, the extensive BMV hemispheres exhibited a significantly lower CBF, CMRO2, CBF/CBV, and CVR (p<0.05) and a significantly higher CBV and OEF than in diminished BMV hemispheres and controls (p<0.05). Except for the CBF in the white matter, the mean hemodynamic and metabolic parameters of the diminished BMV hemispheres were not significantly different from those of the controls. The extensive development of BMVs is a sign of severe hemodynamic impairment in adult patients with ischemic moyamoya disease. The results may not apply to adults with hemorrhagic onset. (author)

  1. Plasma Tissue Factor Pathway Inhibitor Levels in Angiographically Defined Coronary Artery Disease Among Saudis

    Directory of Open Access Journals (Sweden)

    Syed Shahid Habib

    2013-05-01

    Full Text Available Objectives: This study was aimed to determine plasma levels of total (TFPI-T and free (TFPI-F tissue factor pathway inhibitor, plasminogen activator inhibitor-1 (PAI-1, and tissue plasminogen activator (t-PA in a cohort of Saudi patients with chronic stable angiographically defined coronary artery disease (CAD and to determine its correlation with its severity.Methods: This cross sectional study was conducted in the department of physiology and department of cardiology, College of Medicine, and King Khalid University Hospital and King Saud University, Riyadh. Sixty known cases of CAD who had undergone angiography (35 males and 25 females were selected. A control group included 39 (20 males and 19 females healthy subjects. Fasting venous blood samples were analyzed for total (TFPI-T and free (TFPI-F tissue factor pathway inhibitor, plasminogen activator inhibitor-1 (PAI-1, and tissue plasminogen activator (t-PA. Gensini scores and vessel scores were determined for assessing CAD severity.Results: There were non-significant differences between age, body mass index (BMI and Blood pressure between the controls and CAD subjects. A comparison of hemostatic markers between control and CAD patients showed significantly higher levels of Fibrinogen, PAI-1, TFPI-T and TFPI-F in CAD patients compared to control subjects. But there was no difference in plasma t-PA levels. TFPI-T had a significant positive correlation with severity of disease determined by Gensini Scores (r=0.344; p=0.006 and vessel scores (r=0.338; p=0.015.Conclusion: Plasma levels of total tissue factor pathway inhibitor are significantly related with the presence and severity of CAD. Elevated levels of TFPI-T may be considered as useful diagnostic and prognostic markers in patients with CAD.

  2. MYOCARDIAL BRIDGING - CLINICAL AND ANGIOGRAPHIC PROFILE IN LAST 5 YEARS; A STUDY OF 129 CASES

    Directory of Open Access Journals (Sweden)

    Abhilash S P

    2010-11-01

    Full Text Available Aims of study : To assess the clinical and angiographical profile of myocardial bridging from consecutive coronary angiograms done over last 5 years at Medical college, Thiruvananthapuram. To assess the risk of cardiovascular events and the risk of accelerated atherosclerosis in isolated myocardial bridging. Methods : Consecutive coronary angiograms done at Medical college Thiruvananthapuram from 04/02/2005 to 31/03/2010 were reviewed for myocardial bridging. A total of 10492 coronary angiograms were reviewed. Myocardial bridges with systolic lumen reduction of more than 50% were considered for analysis. Quantitative coronary angiography (QCA was used for analysis. Clinical presentation as well as correlation with structural heart disease and coronary heart disease was assessed. Results: Incidence of myocardial bridges was 1.23%. Of the 129 patients with myocardial bridges 63 ( 48.8% had associated significant coronary artery disease. Remaining 66 (51.2% patients presented with isolated bridges. Out of these 66 patients with isolated myocardial bridges, 7 (10.6% patients presented with acute myocardial infarction and 3 (4.5% presented with cardiac arrhythmias. Of the 63 patients with significant coronary disease 11 (17.5% patients had single vessel disease and they had the culprit lesion and myocardial bridge seen in the same vessel. Most common location of myocardial bridge was mid LAD (64.9% followed by distal LAD (23.8%. Length of bridge was 20 mm in 35.7%. Mean percentage of systolic obliteration by the bridge was 74.5%. 100% systolic obliteration was seen in 7.79% of isolated bridges and in 9.79% of bridges with CAD. Among 120 rhuematic heart disease patients who underwent coronary angiogram, 10 (8.3% patients had myocardial bridging. 12.1% of all HCM patients who underwent coronary angiograms had myocardial bridging. Conclusion: Myocardial bridging can be lethal- can accelerate atherosclerosis, can precipitate acute MIs and life

  3. Evaluation and Improved Use of Fecal Occult Blood Test in the Constipated Child.

    Science.gov (United States)

    Kilway, Denise M

    2016-01-01

    This quality improvement project examined the use of fecal occult blood test in the constipated child in a pediatric gastroenterology outpatient clinic. A retrospective chart review was completed on 100 children seen for an initial visit with the gastroenterology provider. The number of fecal occult blood tests performed and the child's coinciding symptoms were tallied and compared with the North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition recommendations. An educational intervention was held with the pediatric gastroenterology providers consisting of a PowerPoint presentation summarizing aims of the quality improvement project and reviewing recommendations for use of fecal occult blood test in the constipated child. Pre- and post-intervention chart review data sets were compared. Results showed a 19.6% decrease in the use of fecal occult blood tests performed during the post-intervention timeframe. However, when used in conjunction with North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition recommendations, the appropriateness of fecal occult blood test use increased by 71.4% in the post-intervention patients. Reviewing the recommendations with gastroenterology providers assisted in optimizing the meaningful use of fecal occult blood test, improving quality and safety of care for children seen in the pediatric gastroenterology outpatient clinic. PMID:27070795

  4. Improving capabilities of broadband differential satellite navigation systems via radio occultation technology

    Science.gov (United States)

    Myslivtsev, T. O.; Nikiforov, S. V.; Pogoreltsev, A. I.; Savochkin, P. V.; Sakhno, I. V.; Semenov, A. A.; Troitsky, B. V.

    2016-07-01

    The existent satellite system for radio occultation monitoring the Earth's neutral atmosphere and ionosphere (COSMIC) provides data to consumers in the regions with limited possibilities of constructing dense measurement networks (e.g., in the World Ocean area). A forthcoming increase of LEO small spacecrafts and the deployment of new satellite radio navigation systems will result in a pronounced increase in the efficiency of radio occultation method and its space resolution. As a result, the Space-Based Augmentation Systems (SBAS) broadband differential system will become global, or the quality of corrections delivered to single-frequency consumers of individual systems, e.g., the Augmentation and Monitoring System, will be improved. Therefore, the methods for processing and analyzing obtained radio occultation data should be improved. A simple method to reconstruct the electron density profile at radio occultation points, based on the total electron content measurement on the satellite-satellite path and the IRI-type ionospheric model has been proposed. The method needs initial information, it does not require refraction measurements, and it is free of the assumption that the ionosphere is spherically stratified in the occultation region. Verification of the proposed method based on data for 121 radio occultation cases across Europe in May 2013 demonstrated good agreement with the vertical sounding data.

  5. Diagnostic accuracy of unenhanced, contrast-enhanced perfusion and angiographic MRI sequences for pulmonary embolism diagnosis: results of independent sequence readings

    International Nuclear Information System (INIS)

    To independently evaluate unenhanced, contrast-enhanced perfusion and angiographic MR sequences for pulmonary embolism (PE) diagnosis. Prospective investigation, including 274 patients who underwent perfusion, unenhanced 2D steady-state-free-precession (SSFP) and contrast-enhanced 3D angiographic MR sequences on a 1.5-T unit, in addition to CTA (CT angiography). Two independent readers evaluated each sequence independently in random order. Sensitivity, specificity, predictive values and inter-reader agreement were calculated for each sequence, excluding sequences judged inconclusive. Sensitivity was also calculated according to PE location. Contrast-enhanced angiographic sequences showed the highest sensitivity (82.9 and 89.7 %, reader 1 and reader 2, respectively), specificity (98.5 and 100 %) and agreement (kappa value 0.77). Unenhanced angiographic sequences, although less sensitive overall (68.7 and 76.4 %), were sensitive for the detection of proximal PE (92.7 and 100 %) and showed high specificity (96.1 and 99.1 %) and good agreement (kappa value 0.62). Perfusion sequences showed lower sensitivity (75.0 and 79.3 %), specificity (84.8 and 89.7 %) and agreement (kappa value 0.51), and a negative predictive value of 84.8 % at best. Compared with contrast-enhanced angiographic sequences, unenhanced sequences demonstrate lower sensitivity, except for proximal PE, but high specificity and agreement. The negative predictive value of perfusion sequences was insufficient to safely rule out PE. (orig.)

  6. Diagnostic accuracy of unenhanced, contrast-enhanced perfusion and angiographic MRI sequences for pulmonary embolism diagnosis: results of independent sequence readings

    Energy Technology Data Exchange (ETDEWEB)

    Revel, Marie Pierre [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Hotel-Dieu, Service de Radiologie, Paris (France); Sanchez, Olivier; Meyer, Guy [Hopital Europeen Georges Pompidou, APHP, Respiratory and intensive care and, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM Unite 765, Paris (France); Lefort, Catherine; Couchon, Sophie; Hernigou, Anne; Frija, Guy [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Niarra, Ralph [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Chatellier, Gilles [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM CIC-EC E4, Paris (France)

    2013-09-15

    To independently evaluate unenhanced, contrast-enhanced perfusion and angiographic MR sequences for pulmonary embolism (PE) diagnosis. Prospective investigation, including 274 patients who underwent perfusion, unenhanced 2D steady-state-free-precession (SSFP) and contrast-enhanced 3D angiographic MR sequences on a 1.5-T unit, in addition to CTA (CT angiography). Two independent readers evaluated each sequence independently in random order. Sensitivity, specificity, predictive values and inter-reader agreement were calculated for each sequence, excluding sequences judged inconclusive. Sensitivity was also calculated according to PE location. Contrast-enhanced angiographic sequences showed the highest sensitivity (82.9 and 89.7 %, reader 1 and reader 2, respectively), specificity (98.5 and 100 %) and agreement (kappa value 0.77). Unenhanced angiographic sequences, although less sensitive overall (68.7 and 76.4 %), were sensitive for the detection of proximal PE (92.7 and 100 %) and showed high specificity (96.1 and 99.1 %) and good agreement (kappa value 0.62). Perfusion sequences showed lower sensitivity (75.0 and 79.3 %), specificity (84.8 and 89.7 %) and agreement (kappa value 0.51), and a negative predictive value of 84.8 % at best. Compared with contrast-enhanced angiographic sequences, unenhanced sequences demonstrate lower sensitivity, except for proximal PE, but high specificity and agreement. The negative predictive value of perfusion sequences was insufficient to safely rule out PE. (orig.)

  7. Occult recurrent colorectal cancer detected by radioimmunoscintigraphy, kinetic analysis and probability mapping and CT co-registration

    International Nuclear Information System (INIS)

    Full text: Tumour uptake of radiolabelled monoclonal antibodies is typically low and may be obscured by background, or difficult to differentiate from vascular activity. Comparison of early and late images by kinetic analysis and probability mapping may define blood pool effects and demonstrate tumour antibody accumulation. In 6 patients with elevated serum carcinoembryonic antigens (CEA) following surgery for colorectal cancer, in whom CT and MRI were negative, whole-body imaging was performed within 30 min and at 3, 6 and 24 h following intravenous administration of 99Tcm-anti-CEA monoclonal antibody (CEA Scan, Immunomedics). While kinetic analysis and probability mapping detected focal abnormalities in planar images in 4 patients, SPET imaging at 3 and 6 h demonstrated lesions in all 6 patients. The anatomical site of these focal accumulations of 99Tcm-anti-CEA MAb activity was identified on CT co-registration; statistical mapping techniques applied to the SPET images may thus be used to define occult recurrent or metastatic colon cancer

  8. Plant Vascular Biology 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Biao

    2014-11-17

    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes. The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.

  9. Vascular cognitive impairment

    Directory of Open Access Journals (Sweden)

    N.V. Vakhnina

    2014-05-01

    Full Text Available Vascular pathology of the brain is the second most common cause of cognitive impairment after Alzheimer's disease. The article describes the modern concepts of etiology, pathogenetic mechanisms, clinical features and approaches to diagnosis and therapy of vascular cognitive impairment (VCI. Cerebrovascular accident, chronic cerebral circulatory insufficiency and their combination, sometimes in combination with a concomitant neurodegenerative process, are shown to be the major types of brain lesions leading to VCI. The clinical presentation of VCI is characterized by the neuropsychological status dominated by impairment of the executive frontal functions (planning, control, attention in combination with focal neurological symptoms. The diagnosis is based on comparing of the revealed neuropsychological and neurological features with neuroimaging data. Neurometabolic, acetylcholinergic, glutamatergic, and other vasoactive drugs and non-pharmacological methods are widely used to treat VCI. 

  10. Pathophysiology of vascular dementia

    Directory of Open Access Journals (Sweden)

    Rizzo Claudia

    2009-11-01

    Full Text Available Abstract The concept of Vascular Dementia (VaD has been recognized for over a century, but its definition and diagnostic criteria remain unclear. Conventional definitions identify the patients too late, miss subjects with cognitive impairment short of dementia, and emphasize consequences rather than causes, the true bases for treatment and prevention. We should throw out current diagnostic categories and describe cognitive impairment clinically and according to commonly agreed instruments that document the demographic data in a standardized manner and undertake a systematic effort to identify the underlying aetiology in each case. Increased effort should be targeted towards the concept of and criteria for Vascular Cognitive Impairment and Post-Stroke Dementia as well as for genetic factors involved, especially as these categories hold promise for early prevention and treatment.

  11. Eagle Syndrome Causing Vascular Compression with Cervical Rotation: Case Report

    Science.gov (United States)

    Demirtaş, Hakan; Kayan, Mustafa; Koyuncuoğlu, Hasan Rıfat; Çelik, Ahmet Orhan; Kara, Mustafa; Şengeze, Nihat

    2016-01-01

    Summary Background Eagle syndrome is a condition caused by an elongated styloid process. Unilateral face, neck and ear pain, stinging pain, foreign body sensation and dysphagia can be observed with this syndrome. Rarely, the elongated styloid process may cause pain by compressing the cervical segment of the internal carotid and the surrounding sympathetic plexus, and that pain spreading along the artery can cause neurological symptoms such as vertigo and syncope. Case Report In this case report we presented a very rare eagle syndrome with neurological symptoms that occurred suddenly with cervical rotation. The symptoms disappeared as suddenly as they occurred, with the release of pressure in neutral position. We also discussed CT angiographic findings of this case. Conclusions Radiological diagnosis of the Eagle syndrome that is manifested with a wide variety of symptoms and causes diagnostic difficulties when it is not considered in the differential diagnosis is easy in patients with specific findings. CT angiography is a fast and effective examination in terms of showing compression in patients with the Eagle syndrome that is considered to be atypical and causes vascular compression. PMID:27354882

  12. Pathophysiology of vascular dementia

    OpenAIRE

    Rizzo Claudia; Duro Giovanni; Iemolo Francesco; Castiglia Laura; Hachinski Vladimir; Caruso Calogero

    2009-01-01

    Abstract The concept of Vascular Dementia (VaD) has been recognized for over a century, but its definition and diagnostic criteria remain unclear. Conventional definitions identify the patients too late, miss subjects with cognitive impairment short of dementia, and emphasize consequences rather than causes, the true bases for treatment and prevention. We should throw out current diagnostic categories and describe cognitive impairment clinically and according to commonly agreed instruments th...

  13. A study of low-density areas, clinical findings, and angiographic findings in patients with cerebral infarction

    International Nuclear Information System (INIS)

    55 out of 62 patients with cerebral infarction were investigated in terms of CT scan findings, angiographic findings, and clinical symptoms. The results obtained were as follows: 1) The low-density areas of the CT scan findings were classified into the following four types: large hemispheric or lobular --Type I; wedge-shaped --Type II; small --Type III; and lacunar low-density area. --Type IV. 2) Almost all patients with angiographically occlusive findings showed low-density areas of Type I; however, one patient with ICA occlusion revealed only a lacunar low-density area. 3) The patients with lacunar low-density areas showed an angiographically delayed filling of the angular artery and posterior parietal artery of the middle cerebral artery. 4) The relationship between the types of low-density areas and the clinical conscious disorders was not clear. On the other hand, the patients with Type I low-density areas almost all had motor disturbances, while patients with other types of low-density areas showed only 60 - 70% motor disturbances. 5) In patients with speech disorders, total aphasia cases were found in patients with large hemispheric low-density areas on the left side. Although, motor aphasia cases were seen in patients with various low-density areas on the left inferior frontal and precentral gyri, dysarthria cases were found in the patients with several low-density areas on both sides. 6) The localization of lacunar low-density areas seemed to be near the caudate nucleus on the right side and in the putaminal regions on the left side. The mean and the standard deviation of CT numbers in the lacunar low-density areas showed higher values on the right side than on the left side. (author)

  14. Update on Vascular Dementia.

    Science.gov (United States)

    Khan, Ayesha; Kalaria, Raj N; Corbett, Anne; Ballard, Clive

    2016-09-01

    Vascular dementia (VaD) is a major contributor to the dementia syndrome and is described as having problems with reasoning, planning, judgment, and memory caused by impaired blood flow to the brain and damage to the blood vessels resulting from events such as stroke. There are a variety of etiologies that contribute to the development of vascular cognitive impairment and VaD, and these are often associated with other dementia-related pathologies such as Alzheimer disease. The diagnosis of VaD is difficult due to the number and types of lesions and their locations in the brain. Factors that increase the risk of vascular diseases such as stroke, high blood pressure, high cholesterol, and smoking also raise the risk of VaD. Therefore, controlling these risk factors can help lower the chances of developing VaD. This update describes the subtypes of VaD, with details of their complex presentation, associated pathological lesions, and issues with diagnosis, prevention, and treatment. PMID:27502303

  15. Vascular Cambium Development

    Science.gov (United States)

    Nieminen, Kaisa; Blomster, Tiina; Helariutta, Ykä; Mähönen, Ari Pekka

    2015-01-01

    Secondary phloem and xylem tissues are produced through the activity of vascular cambium, the cylindrical secondary meristem which arises among the primary plant tissues. Most dicotyledonous species undergo secondary development, among them Arabidopsis. Despite its small size and herbaceous nature, Arabidopsis displays prominent secondary growth in several organs, including the root, hypocotyl and shoot. Together with the vast genetic resources and molecular research methods available for it, this has made Arabidopsis a versatile and accessible model organism for studying cambial development and wood formation. In this review, we discuss and compare the development and function of the vascular cambium in the Arabidopsis root, hypocotyl, and shoot. We describe the current understanding of the molecular regulation of vascular cambium and compare it to the function of primary meristems. We conclude with a look at the future prospects of cambium research, including opportunities provided by phenotyping and modelling approaches, complemented by studies of natural variation and comparative genetic studies in perennial and woody plant species. PMID:26078728

  16. Age-Related Alteration of Risk Profile, Inflammatory Response, and Angiographic Findings in Patients with Acute Coronary Syndrome

    Directory of Open Access Journals (Sweden)

    Hala Mahfouz Badran

    2009-01-01

    Full Text Available Background: Coronary artery disease (CAD is a major public health problem which in turn imposes a significant burden on health care systems because of high morbidity and mortality. Although the multifactorial etiology of CAD increases with age, but in recent years, the incidence is increasing among younger age groups.Objectives: In this study we aimed to evaluate the effect of age on risk profile, inflammatory response and the angiographic findings in patients with ACS.Patients and Methods: The study comprised 253 ACS patients. Seventy six (30% with UA, 56 (22% with NSTEMI and 121(48% with STEMI diagnosis. The value of Hs-CRP, lipid profile, cardiac enzymes, risk factors, EF% and angiographic score were analyzed and compared in different age groups.Results: Group 1 (n = 68 with age 45 years, group II (n = 110 with age 45–65 years and group III (n = 75 65 years. Group I had more prevalence of male sex, smoking, family history, hypertriglyceridemia and low levels of HDL (P 0.01, higher incidence of STEMI (P 0.01 and lower prevalence of UA (P 0.01. Diabetes mellitus, hypertension, and female gender were more common in older groups. Hs-CRP was significantly lower in the young age (group I. Group I showed a preponderance of single-vessel disease, lower coronary atherosclerotic score and prevalent left anterior descending artery (LAD involvement compared with older age groups. Hs-CRP was positively correlated to severity of CAD only in older groups. Stepwise multiple regression analysis showed that age, male gender, cardiac enzymes and EF% were common predictors of multivessel disease. Smoking was independent predictor in young patients 45 years while diabetes and Hs-CRP was the key predictor in older patient groups.Conclusion: Young patients with ACS had different clinical, angiographic and biochemical profile. Hs-CRP peak concentration did not correlate with angiographic findings in young patients that could be attributed to different risk profile

  17. Orbit dynamics and geographical coverage capabilities of satellite-based solar occultation experiments for global monitoring of stratospheric constituents

    Science.gov (United States)

    Brooks, D. R.

    1980-01-01

    Orbit dynamics of the solar occultation technique for satellite measurements of the Earth's atmosphere are described. A one-year mission is simulated and the orbit and mission design implications are discussed in detail. Geographical coverage capabilities are examined parametrically for a range of orbit conditions. The hypothetical mission is used to produce a simulated one-year data base of solar occultation measurements; each occultation event is assumed to produce a single number, or 'measurement' and some statistical properties of the data set are examined. A simple model is fitted to the data to demonstrate a procedure for examining global distributions of atmospheric constitutents with the solar occultation technique.

  18. Multiple arterial anomalies in the newborn infant. Echocardiographic and angiographic diagnosis

    Directory of Open Access Journals (Sweden)

    Ivan Romero Rivera

    2000-08-01

    Full Text Available Multiple arterial anomalies characterized by tortuosity and rolling of the pulmonary arteries and aorta were diagnosed on echocardiography in an asymptomatic newborn infant with a phenotype suggesting Ehlers-Danlos syndrome. These changes were later confirmed on angiography, which also showed peripheral vascular abnormalities. The electrocardiogram showed a probable hemiblock of the left anterosuperior branch, and the chest x-ray showed an excavated pulmonary trunk with normal pulmonary flow.

  19. Experimentally induced tumors used for angiographic estimation of embolisation and cytostatic treatment

    International Nuclear Information System (INIS)

    In 12 rats tumors have been induced chemically by intraperitoneal application of dimethylnitrosamine. This method is simple and reliable and the effect of tumor embolisation can be followed easyly. Thymus aplastic nude mice with transplanted human tumors deserve strict care. Tumor microangiograms of 48 animals demonstrate a close similarity with angiograms of corresponding human tumors. The vascular pattern does not alterate after several transplantations, after cytostatic therapy a slight hypervascularisation developes. (orig.)

  20. Interventional method in diagnosis and treatment of vascular complication after liver transplantation

    International Nuclear Information System (INIS)

    Objective: To evaluate the role of interventional method in the diagnosis and treatment of vascular complication after liver transplantation. Methods: Seven patients (3 vena cava stenosis, 1 hepatic artery stenosis, 2 hepatic artery thrombosis, and 1 hepatic artery pseudo-aneurysm) with vascular complication after liver transplantation had been studied retrospectively, including the correlative biochemistry data and angiographic signs. Results: Among the 7 patients, 6 patients had been successfully treated by interventional radiology procedure. The technical success rate was 85.56%. The renal functions of 3 patients with vena cava stenosis who had been treated by angioplasty improved satisfactorily. The survival time after this intervention of these 3 patients ranged from 10 days to 20 months. 1 patient still lived 20 months after the intervention, 2 died of other complications beside caval stenosis within one month after the intervention. The hepatic function of the 4 patients with hepatic artery complications treated by interventional procedures had not been redressed. Conclusion: Angiography played an important role in diagnosing the hepatic vascular complication after liver transplantation. The result of interventional radiology treatment of vena cava stenosis was encouraging

  1. Vertical Distribution of Gases and Aerosols in Titan's Atmosphere Observed by VIMS/Cassini Solar Occultations

    Science.gov (United States)

    Maltagliati, Luca; Vinatier, Sandrine; Sicardy, Bruno; Bézard, Bruno; Sotin, Christophe; Nicholson, Philip D.; Hedman, Matt; Brown, Robert H.; Baines, Kevin; Buratti, Bonnie; Clark, Robert

    2013-04-01

    We present the vertical distribution of gaseous species and aerosols in Titan's atmosphere through the analysis of VIMS solar occultations. We employ the infrared channel of VIMS, which covers the 1 - 5 μm wavelength range. VIMS occultations can provide good vertical resolution (~10 km) and an extended altitude range (from 70 to 700 km), complementing well the information from other Cassini instruments. VIMS has retrieved 10 solar occultations up to now. They are distributed through the whole Cassini mission and they probe different latitudes in both hemispheres. Two main gases can be observed by VIMS occultations: methane, through its bands at 1.2, 1.4, 1.7, 2.3 and 3.3 μm, and CO, at 4.7 μm. We can extract methane's abundance between 70 and 750 km and CO's between 70 and 180 km. Regarding aerosols, the VIMS altitude range allows to get information on the properties of both the main haze and the detached layer. Aerosols also affect the transmittance through their spectral signatures. In particular, a spectral signature at 3.4 μm that was attributed to aerosols was recently discovered by the analysis of the first VIMS occultation. We will monitor the latitudinal and temporal variations of the 3.4 μm feature through various occultations. A change in the global circulation regime of Titan sets in with the approaching to the vernal equinox, and a strong decrease of the altitude of the detached layer between the winter solstice and the equinox has indeed been observed. The temporal coverage of VIMS occultations allows the study the effect of these variations in the vertical distribution of aerosol optical and spectral properties.

  2. Occultation Modeling for Radiation Obstruction Effects on Spacecraft Systems

    Science.gov (United States)

    de Carufel, Guy; Li, Zu Qun; Harvey, Jason; Crues, Edwin Z.; Bielski, Paul

    2016-01-01

    A geometric occultation model has been developed to determine line-of-sight obstruction of radiation sources expected for different NASA space exploration mission designs. Example applications includes fidelity improvements for surface lighting conditions, radiation pressure, thermal and power subsystem modeling. The model makes use of geometric two dimensional shape primitives to most effectively model space vehicles. A set of these primitives is used to represent three dimensional obstructing objects as a two dimensional outline from the perspective of an observing point of interest. Radiation sources, such as the Sun or a Moon's albedo is represented as a collection of points, each of which is assigned a flux value to represent a section of the radiation source. Planetary bodies, such as a Martian moon, is represented as a collection of triangular facets which are distributed in spherical height fields for optimization. These design aspects and the overall model architecture will be presented. Specific uses to be presented includes a study of the lighting condition on Phobos for a possible future surface mission, and computing the incident flux on a spacecraft's solar panels and radiators from direct and reflected solar radiation subject to self-shadowing or shadowing by third bodies.

  3. Pluto's atmosphere from stellar occultations in 2012 and 2013

    CERN Document Server

    Dias-Oliveira, A; Lellouch, E; Vieira-Martins, R; Assafin, M; Camargo, J I B; Braga-Ribas, F; Gomes-Júnior, A R; Benedetti-Rossi, G; Colas, F; Decock, A; Doressoundiram, A; Dumas, C; Emilio, M; Polleri, J Fabrega; Gil-Hutton, R; Gillon, M; Girard, J; Hau, G; Ivanov, V D; Jehin, E; Lecacheux, J; Leiva, R; Lopez-Sisterna, C; Mancini, L; Maury, A; Meza, E; Morales, N; Nagy, L; Opitom, C; Ortiz, J L; Pollock, J; Roques, F; Snodgrass, C; Soulier, J F; Thirouin, A; Vanzi, L; Widemann, T; Reichart, D E; LaCluyze, A P; Haislip, J B; Ivarsen, K M; Dominik, M; Jørgensen, U; Skottfelt, J

    2015-01-01

    We analyze two multi-chord stellar occultations by Pluto observed on July 18th, 2012 and May 4th, 2013, and monitored respectively from five and six sites. They provide a total of fifteen light-curves, twelve of them being used for a simultaneous fit that uses a unique temperature profile, assuming a clear (no-haze) and pure N_2 atmosphere, but allowing for a possible pressure variation between the two dates. We find a solution that fits satisfactorily (i.e. within the noise level) all the twelve light-curves, providing atmospheric constraints between ~1,190 km (pressure ~ 11 \\mubar) and ~ 1,450 km (pressure ~0.1 \\mubar) from Pluto's center. Our main results are: (1) the best-fitting temperature profile shows a stratosphere with strong positive gradient between 1,190 km (at 36 K, 11 \\mubar) and r = 1,215 km (6.0 \\mubar), where a temperature maximum of 110 K is reached; above it is a mesosphere with negative thermal gradient of -0.2 K/km up to ~ 1,390 km (0.25 \\mubar), where, the mesosphere connects itself to ...

  4. Occult bony lesions associated with anterior cruciate ligament injury

    International Nuclear Information System (INIS)

    To examine bony lesions associated with anterior cruciate ligament (ACL) injuries, magnetic resonance (MR) imaging was performed on 55 knees with ACL injuries. With respect to the period between ACL injuries and MR imaging, the knees were divided into acute (within one month), subacute (from one month to one year) and chronic (over one year) groups, containing 19, 16 and 20 knees, respectively. Occult bony lesions not shown in roentgenography were observed more frequently in the acute group (13/19) than in the other two groups (subacute group, 5/16; chronic group, 1/20), located in the lateral compartment of the knee joint. In the acute group, bony lesions had high signal intensity on T2-weighted images and low signal intensity on proton density images. In the subacute and chronic groups, bony lesions were less pronounced and had low signal intensity on T2-weighted images. These findings suggest that bony lesions are frequently associated with and occur simultaneously with ACL injury. (author)

  5. Exploring atmospheric blocking with GPS radio occultation observations

    Science.gov (United States)

    Brunner, Lukas; Steiner, Andrea K.; Scherllin-Pirscher, Barbara; Jury, Martin W.

    2016-04-01

    Atmospheric blocking has been closely investigated in recent years due to its impact on weather and climate, such as heat waves, droughts, and flooding. We use, for the first time, satellite-based observations from Global Positioning System (GPS) radio occultation (RO) and explore their ability to resolve blocking in order to potentially open up new avenues complementing models and reanalyses. RO delivers globally available and vertically highly resolved profiles of atmospheric variables such as temperature and geopotential height (GPH). Applying a standard blocking detection algorithm, we find that RO data robustly capture blocking as demonstrated for two well-known blocking events over Russia in summer 2010 and over Greenland in late winter 2013. During blocking episodes, vertically resolved GPH gradients show a distinct anomalous behavior compared to climatological conditions up to 300 hPa and sometimes even further up into the tropopause. The accompanying increase in GPH of up to 300 m in the upper troposphere yields a pronounced tropopause height increase. Corresponding temperatures rise up to 10 K in the middle and lower troposphere. These results demonstrate the feasibility and potential of RO to detect and resolve blocking and in particular to explore the vertical structure of the atmosphere during blocking episodes. This new observation-based view is available globally at the same quality so that blocking in the Southern Hemisphere can also be studied with the same reliability as in the Northern Hemisphere.

  6. Occult head injury: its incidence in spinal cord injury.

    Science.gov (United States)

    Wilmot, C B; Cope, D N; Hall, K M; Acker, M

    1985-04-01

    This study investigated the suspicion that a significant proportion of individuals having spinal cord injury (SCI) also sustain a concomitant undiagnosed occult head injury during the trauma accident. The criteria for high risk of head injury included the following: (1) quadriplegia with high energy deceleration accident, (2) loss of consciousness at time of injury, (3) brainstem or cortical neurologic indicators, or (4) respiratory support required at time of injury. In this study, 67 patients admitted to the rehabilitation unit were given a neuropsychologic evaluation a median of 48 days after injury. Motor free scales used were the Galveston Orientation and Amnesia Test (GOAT), Quick Test, Raven Progressive matrices, serial 7s, Shipley Hartford, Stroop Color/Word Interference, and the Wechsler Memory Scale Associate Learning Tests. Forty-three of the 67 patients (64%) scored mildly to profoundly impaired on the test battery. Evidence of poor premorbid academic history was present in 19 (44%) of those with impaired performance on the neurologic evaluation and in only three (13%) of those scoring unimpaired. Consequently, 56% (24/43) of the impaired had no previous record of scholastic difficulties, presumably acquiring cognitive impairment at the time of injury. The implications of this high incidence of impaired cognitive functioning for treatment of individuals with SCI are significant. PMID:3985774

  7. Occult hepatitis C virus infection among Egyptian hemodialysis patients.

    Science.gov (United States)

    Abdelrahim, Soha S; Khairy, Rasha; Esmail, Mona Abdel-Monem; Ragab, Mahmoud; Abdel-Hamid, Mohamed; Abdelwahab, Sayed F

    2016-08-01

    Occult hepatitis C virus (HCV) infection (OCI) was reported in an apparently disease-free state in the absence of liver disease, anti-HCV and HCV-RNA in the serum. The existing data examining the clinical significance of OCI and its potential as a source of HCV infection among hemodialysis patients are very limited. We examined the presence of OCI among patients on maintenance hemodialysis at Minia Governorate, Egypt; an HCV endemic country. A total of 81 subjects with negative markers for HCV were enrolled. HCV-RNA was tested in PBMCs by real-time PCR. For the 81 subjects, the average dialysis duration was 32.7 ± 21.7 months and the average ALT level (±SD) was 26 ± 12 U/L while that of AST was 29 ± 16 U/L. Out of the 81 subjects, three (3.7%) were HCV-RNA positive in PBMCs in the absence of serum anti-HCV and HCV-RNA indicating OCI. The viral load of the OCI subjects ranged from 172 to 4150 IU/ml. History of liver disease was positive in one of the three positive patients. These results highlight the potential risk of HCV transmission from patients within hemodialysis units in Egypt. J. Med. Virol. 88:1388-1393, 2016. © 2016 Wiley Periodicals, Inc. PMID:26743014

  8. Cassini-VIMS at Jupiter: Solar occultation measurements using Io

    Science.gov (United States)

    Formisano, V.; D'Aversa, E.; Bellucci, G.; Baines, K.H.; Bibring, J.-P.; Brown, R.H.; Buratti, B.J.; Capaccioni, F.; Cerroni, P.; Clark, R.N.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Jaumann, R.; Langevin, Y.; Matson, D.L.; McCord, T.B.; Mennella, V.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, C.; Chamberlain, M.C.; Hansen, G.; Hibbits, K.; Showalter, M.; Filacchione, G.

    2003-01-01

    We report unusual and somewhat unexpected observations of the jovian satellite Io, showing strong methane absorption bands. These observations were made by the Cassini VIMS experiment during the Jupiter flyby of December/January 2000/2001. The explanation is straightforward: Entering or exiting from Jupiter's shadow during an eclipse, Io is illuminated by solar light which has transited the atmosphere of Jupiter. This light, therefore becomes imprinted with the spectral signature of Jupiter's upper atmosphere, which includes strong atmospheric methane absorption bands. Intercepting solar light refracted by the jovian atmosphere, Io essentially becomes a "miffor" for solar occultation events of Jupiter. The thickness of the layer where refracted solar light is observed is so large (more than 3000 km at Io's orbit), that we can foresee a nearly continuous multi-year period of similar events at Saturn, utilizing the large and bright ring system. During Cassini's 4-year nominal mission, this probing tecnique should reveal information of Saturn's atmosphere over a large range of southern latitudes and times. ?? 2003 Elsevier Inc. All rights reserved.

  9. Stratospheric gravity wave momentum flux from radio occultations

    Science.gov (United States)

    Schmidt, T.; Alexander, P.; Torre, A.

    2016-05-01

    Triples of GPS radio occultation (RO) temperature data are used to derive horizontal and vertical gravity wave (GW) parameters in the stratosphere between 20 km and 40 km from which the vertical flux of horizontal momentum is determined. Compared to previous studies using RO data, better limiting values for the sampling distance (Δd≤250 km) and the time interval (Δt≤15 min) are used. For several latitude bands the mean momentum fluxes (MFs) derived in this study are considerably larger than MF from other satellite missions based on horizontal wavelengths calculated between two adjacent temperature profiles along the satellite track. Error sources for the estimation of MF from RO data and the geometrical setup for the applied method are investigated. Another crucial issue discussed in this paper is the influence of different background separation methods to the final MF. For GW analysis a measured temperature profile is divided into a fluctuation and a background and it is assumed that the fluctuation is caused by GWs only. For the background separation, i.e., the detrending of large-scale processes from the measured temperature profile, several methods exist. In this study we compare different detrending approaches and for the first time an attempt is made to detrend RO data with ERA-Interim data from the European Centre for Medium-Range Weather Forecasts. We demonstrate that the horizontal detrending based on RO data and ERA-Interim gives more consistent results compared with a vertical detrending.

  10. Exploring atmospheric blocking with GPS radio occultation observations

    Directory of Open Access Journals (Sweden)

    L. Brunner

    2015-12-01

    Full Text Available Atmospheric blocking has been closely investigated in recent years due to its impact on weather and climate, such as heat waves, droughts, and flooding. We use, for the first time, satellite-based observations from Global Positioning System (GPS radio occultation (RO and explore their ability to resolve blocking in order to potentially open up new avenues complementing models and re-analyses. RO delivers globally available and vertically high resolved profiles of atmospheric variables such as temperature and geopotential height (GPH. Applying a standard blocking detection algorithm we find that RO data robustly capture blocking as demonstrated for two well-known blocking events over Russia in summer 2010 and over Greenland in late winter 2013. During blocking episodes, vertically resolved GPH gradients show a distinct anomalous behavior compared to climatological conditions up to 300 hPa and sometimes even further up to the tropopause. The accompanied increase in GPH of up to 300 m in the upper troposphere yields a pronounced tropopause height increase. Corresponding temperatures rise up to 10 K in the middle and lower troposphere. These results demonstrate the feasibility and potential of RO to detect and resolve blocking and in particular to explore the vertical structure of the atmosphere during blocking episodes. This new observation-based view is available globally at the same quality so that also blocking in the Southern Hemisphere can be studied with the same reliability as in the Northern Hemisphere.

  11. Halogen occultation experiment (HALOE) performance verification test procedure

    Science.gov (United States)

    Mauldin, L. E., III

    1986-01-01

    The Performance Verification Test Procedure is given for the Halogen Occultation Experiment (HALOE) instrument, which is being developed in house at the Langley Research Center for the Upper Atmosphere Research Satellite (UARS). This procedure is used for comprehensive performance testing of the HALOE instrument which occurs before, during, and after flight environmental tests. The radiometric performance tests include noise, drift, linearity, instantaneous field-of-view, cal wheel gas cell characterization, and self thermal emissions. Pointer/tracker performance tests include sun sensor performance, gimbal performance, control system performance, and boresight alignment. In addition, the instrument is tested functionally in simulated orbit sequences and all command operating modes are exercised. The data analysis required for each test is specified and pass/fail criteria are given where applicable. This test will fully demonstrate the HALOE instrument's ability to achieve science mission requirements. The HALOE instrument is a gas correlation radiometer that measures vertical distribution of eight upper atmospheric constituents: O3, HCl, HF, NO, CH4, H2O, NO2, and CO2.

  12. Assimilation of GNSS radio occultation observations in GRAPES

    Science.gov (United States)

    Liu, Y.; Xue, J.

    2014-07-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction) analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3) satellites, the research status of the RO of FY-3 satellites is also presented.

  13. Assimilation of GNSS radio occultation observations in GRAPES

    Directory of Open Access Journals (Sweden)

    Y. Liu

    2014-07-01

    Full Text Available This paper reviews the development of the global navigation satellite system (GNSS radio occultation (RO observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3 satellites, the research status of the RO of FY-3 satellites is also presented.

  14. SOLAR OCCULTATION BY TITAN MEASURED BY CASSINI/UVIS

    Energy Technology Data Exchange (ETDEWEB)

    Capalbo, Fernando J.; Benilan, Yves [Laboratoire Interuniversitaire des Systemes Atmospheriques (LISA), UMR 7583 du CNRS, Universites Paris Est Creteil (UPEC) and Paris Diderot - UPD, 61 avenue du General de Gaulle, 94010 Creteil Cedex (France); Yelle, Roger V.; Koskinen, Tommi T.; Sandel, Bill R. [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721 (United States); Holsclaw, Gregory M.; McClintock, William E., E-mail: fernando.capalbo@lisa.u-pec.fr [Laboratory for Atmospheric and Space Physics, University of Colorado, 3665 Discovery Drive, Boulder, CO 80303 (United States)

    2013-04-01

    We present the first published analysis of a solar occultation by Titan's atmosphere measured by the Ultraviolet Imaging Spectrograph on board Cassini. The data were measured during flyby T53 in 2009 April and correspond to latitudes between 21 Degree-Sign and 28 Degree-Sign south. The analysis utilizes the absorption of two solar emission lines (584 A and 630 A) in the ionization continuum of the N{sub 2} absorption cross section and solar emission lines around 1085 A where absorption is due to CH{sub 4}. The measured transmission at these wavelengths provides a direct estimate of the N{sub 2} and CH{sub 4} column densities along the line of sight from the spacecraft to the Sun, which we inverted to obtain the number densities. The high signal-to-noise ratio of the data allowed us to retrieve density profiles in the altitude range 1120-1400 km for nitrogen and 850-1300 km for methane. We find an N{sub 2} scale height of {approx}76 km and a temperature of {approx}153 K. Our results are in general agreement with those from previous work, although there are some differences. Particularly, our profiles agree, considering uncertainties, with the density profiles derived from the Voyager 1 Ultraviolet Spectrograph data, and with in situ measurements by the Ion Neutral Mass Spectrometer with revised calibration.

  15. Occult radiological effects of lipomatosis of the lumbosacral plexus

    Energy Technology Data Exchange (ETDEWEB)

    Mahan, Mark A. [Barrow Neurological Institute, Phoenix, AZ (United States); Howe, B.M.; Amrami, Kimberly K. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Spinner, Robert J. [Mayo Clinic, Department of Neurosurgery, Rochester, MN (United States); Mayo Clinic, Department of Orthopedics, Rochester, MN (United States); Mayo Clinic, Rochester, MN (United States)

    2014-07-15

    Lipomatosis of nerve (LN) is a condition of massive peripheral nerve enlargement frequently associated with hypertrophy within the distribution of the nerve, and most commonly affecting the distal limbs. We sought to understand if LN of the lumbosacral plexus would be associated with the trophic effects of LN on surrounding tissue within the pelvis, which may be clinically occult, but present on MRI. Fifty-one cases of LN, confirmed by pathology or pathognomonic appearance on MRI, were reviewed. Patients with LN of the sciatic nerve were investigated for radiological signs suggestive of overgrowth. Five patients had involvement of the sciatic nerve, 4 of whom had MR imaging of the pelvis. Three patients had LN involving the lumbosacral plexus, and one patient had isolated involvement of the sciatic nerve. All patients with involvement of the lumbosacral plexus demonstrated previously unrecognized evidence of nerve territory overgrowth in the pelvis, including: LN, profound adipose proliferation, muscle atrophy and fatty infiltration, and bone hypertrophy and ankylosis. The patient with LN involving the intrapelvic sciatic nerve, but not the lumbosacral plexus did not demonstrate any radiological evidence of pelvic overgrowth. LN is broader in anatomical reach than previously understood. Proximal plexal innervation may be involved, with a consequent effect on axial skeleton and intrapelvic structures. (orig.)

  16. Survival of occult practices and ideas in modern common sense.

    Science.gov (United States)

    Doering-Manteuffel, Sabine

    2011-05-01

    For a long time rationalism and materialism were the most important ideological undercurrents of the Western world. Since the Enlightenment, in the eighteenth century, they have influenced the Age of Reason. During the past few decades, the so-called New Age originated strong counter-movements have produced a huge number of different new world-views. They are to be considered as part of the wide field of occultism, and run out in different directions. The belief in angels and in the power of fate, the communication with the dead, and the conviction of a life after death are all expressions of a desire to transcend and of a search for higher powers that watch over each person. Additionally, helpers and healers have created a marketplace to promote esoteric services. Media usage, the need to transcend and this new market interested in the magical signal a new era of consciousness in which reason and technology do not contradict mysticism and the transmission of wisdom: these go, instead, hand in hand. PMID:21796880

  17. Atmospheric diurnal variations observed with GPS radio occultation soundings

    Directory of Open Access Journals (Sweden)

    F. Xie

    2010-07-01

    Full Text Available The diurnal variation, driven by solar forcing, is a fundamental mode in the Earth's weather and climate system. Radio occultation (RO measurements from the six COSMIC satellites (Constellation Observing System for Meteorology, Ionosphere and Climate provide nearly uniform global coverage with high vertical resolution, all-weather and diurnal sampling capability. This paper analyzes the diurnal variations of temperature and refractivity from three-year (2007–2009 COSMIC RO measurements in the troposphere and stratosphere between 30° S and 30° N. The RO observations reveal both propagating and trapped vertical structures of diurnal variations, including transition regions near the tropopause where data with high vertical resolution are critical. In the tropics the diurnal amplitude in refractivity shows the minimum around 14 km and increases to a local maximum around 32 km in the stratosphere. The upward propagating component of the migrating diurnal tides in the tropics is clearly captured by the GPS RO measurements, which show a downward progression in phase from stratopause to the upper troposphere with a vertical wavelength of about 25 km. At ~32 km the seasonal variation of the tidal amplitude maximizes at the opposite side of the equator relative to the solar forcing. The vertical structure of tidal amplitude shows strong seasonal variations and becomes asymmetric along the equator and tilted toward the summer hemisphere in the solstice months. Such asymmetry becomes less prominent in equinox months.

  18. Grazing Occultation reveals Gravity Wave Breaking in Pluto's High Atmosphere

    Science.gov (United States)

    Kern, Susan D.; McCarthy, D. W.; Kulesa, C. A.; Hubbard, W. B.; Person, M. J.; Elliot, J. L.; Gulbis, A. A.

    2007-10-01

    Occultation observations of the star P445.3 (2UCAC 25823784; McDonald & Elliot 2000, AJ 120, 1599) by (134340) Pluto on 2007 March 18.453 UT were simultaneously collected in visible and H-band wavelengths from the 6.5-m MMT (Mt. Hopkins) in Arizona. The event was grazing and slow (6.77 km/s), lasting 4 minutes. These conditions facilitated the detection of large-scale, nearly limb-aligned features in Pluto's atmosphere over a pressure range of 0.1-0.7 μbar (0.01-0.07 Pa; radius range of 1500-1350 km). The data are high signal-to-noise and show these features to be fully resolved and achromatic. The scintillation increases with depth in Pluto's atmosphere and indicates a high-frequency cutoff operating on a broad-band spectrum of gravity waves generated deeper in Pluto's atmosphere. The data are in excellent agreement with atmospheric gravity wave theory (Fritts 1984, RGSP 22, 275). Observations reported here were obtained at the MMT Observatory, a joint facility of The University of Arizona and the Smithsonian Institution. The integration and alignment of both cameras was funded by the Astronomy Camp science education program. We also acknowledge support from NASA's Planetary Astronomy Program via grants NNG04GE48G and NNG04GF25G.

  19. Relationship between carotid intima-media thickness and coronary angiographic findings: a prospective study

    Directory of Open Access Journals (Sweden)

    Kilickesmez Kadriye O

    2009-12-01

    Full Text Available Abstract Background Since cardiovascular diseases are associated with high mortality and generally undiagnosed before the onset of clinical findings, there is a need for a reliable tool for early diagnosis. Carotid intima-media thickness (CIMT is a non-invasive marker of coronary artery disease (CAD and is widely used in practice as an inexpensive, reliable, and reproducible method. In the current study, we aimed to investigate prospectively the relationship of CIMT with the presence and extent of significant coronary artery narrowing in patients evaluated by coronary angiography for stable angina pectoris. Methods One hundred consecutive patients with stable angina pectoris and documented ischemia on a stress test were included in the study. The patients were divided into two groups according to the result of the coronary angiography: group 1 (39 patients without a noncritical coronary lesion, and group 2 (61 patients having at least one lesion more than 50% within the main branches of the coronary arteries. All of the patients underwent carotid Doppler ultrasound examination for measurement of the CIMT by a radiologist blinded to the angiographic data. Results The mean CIMT was 0.78 ± 0.21 mm in Group 1, while it was 1.48 ± 0.28 mm in Group 2 (p = 0.001. The mean CIMT in patients with single vessel disease, multi-vessel disease, and left main coronary artery disease were significantly higher compared to Group 1 (1.2 ± 0.34 mm, p = 0.02; 1.6 ± 0.32 mm, p = 0.001; and 1.8 ± 0.31 mm, p = 0.0001, respectively. Logistic regression analysis identified CIMT (OR 4.3, p Conclusions The findings of this study show that increase in CIMT is associated with the presence and extent of CAD. In conclusion, we demonstrated the usefulness of carotid intima-media thickness in predicting coronary artery disease but large-scale studies are required to define its role in clinical practice.

  20. [How Treatable is Vascular Dementia?].

    Science.gov (United States)

    Mori, Etsuro

    2016-04-01

    Vascular dementia is an umbrella term, encompassing the pathological changes in the brain due to cerebrovascular disease that result in dementia. Vascular dementia is the second most common form of dementia, after Alzheimer's disease. In this paper, I outline the concept of vascular dementia, the key aspects of the disease that are yet to be clarified, and the current status of clinical trials. Assessing these factors, I discuss how treatable vascular dementia presently is. Use of the term'vascular dementia'is riddled with uncertainties regarding disease classification, and non-standardized diagnostic criteria. There are difficulties in determining the exact relationship between cerebrovascular pathology and cognitive impairment. The comorbid effects of Alzheimer's pathology in some individuals also present an obstacle to reliable clinical diagnosis, and hinder research into effective management approaches. Vascular dementia is preventable and treatable, as there are established primary and secondary prevention measures for the causative cerebrovascular diseases, such as vascular risk factor intervention, antiplatelet therapy, and anticoagulation, amongst others. However, unlike Alzheimer's disease, there are no established symptomatic treatments for vascular dementia. Clinical trials of cholinesterase inhibitors and memantine indicate that they produce small cognitive benefits in patients with vascular dementia, though the exact clinical significance of these is uncertain. Data are insufficient to support the widespread use of these drugs in vascular dementia. Rehabilitation and physical and cognitive exercise may be beneficial, but evidence of cognitive benefit and relief of neuropsychiatric symptoms due to exercise is lacking. PMID:27056862

  1. The Vascular Depression Hypothesis: Mechanisms Linking Vascular Disease with Depression

    OpenAIRE

    Taylor, Warren D.; Aizenstein, Howard J.; Alexopoulos, George S.

    2013-01-01

    The ‘Vascular Depression’ hypothesis posits that cerebrovascular disease may predispose, precipitate, or perpetuate some geriatric depressive syndromes. This hypothesis stimulated much research that has improved our understanding of the complex relationships between late-life depression (LLD), vascular risk factors, and cognition. Succinctly, there are well-established relationships between late-life depression, vascular risk factors, and cerebral hyperintensities, the radiological hallmark o...

  2. Clinical applications of MR digital subtraction angiography for the evaluation of intracranial vascular and tumorous lesions

    International Nuclear Information System (INIS)

    MR digital subtraction angiography (MR DSA), which is performed by a rapid two-dimensional T1-weighted sequence in combination with bolus injection of gadolinium-based contrast agent was applied to the evaluation of cerebral arteriovenous malformations (AVMs), brain tumors (intraaxial and extraaxial tumors), and other vascular lesions. This study was performed to evaluate the clinical usefulness of the method in the diagnosis of these lesions. We studied 19 cases of cerebral AVM, 36 cases of intraaxial tumor (metastatic brain tumors in 14, glioblastomas in five, astrocytomas in eight, malignant lymphomas in four, pineal tumors in two, and other tumors, in three), 34 cases of extraaxial tumor (meningiomas in 29, and pituitary adenomas in five), and 10 cases of other vascular lesions (cerebral aneurysms in five, venous thrombosis in two, and other lesion in three). For cerebral AVMs, the feeder, nidus, and drainer were evaluated on a 4 - point grading scale (0=poor, 1=fair, 2=good, 3=excellent), and the results obtained were compared with those of conventional cerebral angiography or MR angiography using the postcontrast three-dimensional time-of-flight method. Brain tumors were classified into six enhancement patterns, and were compared with the findings of conventional cerebral angiography. Other vascular lesions were assessed visually. All cases were evaluated independently by two radiologists, and inter-observer agreement was assessed using the κ-test. In all cerebral AVM cases, the hemodynamics of the feeder, nidus, and drainer could be observed. In all but five brain tumor cases, tumor stain could be confirmed in MR DSA images. The findings of tumor stain corresponded to those of cerebral angiographic images. For other vascular lesions, results of lesion detection and lesion morphology were almost in congruence with other methods. MR DSA provides information on the hemodynamics of vascular and tumorous lesions. When used in conjunction with routine MR imaging

  3. Clinical applications of MR digital subtraction angiography for the evaluation of intracranial vascular and tumorous lesions

    Energy Technology Data Exchange (ETDEWEB)

    Katase, Shichiro; Tsuchiya, Kazuhiro; Hachiya, Junichi [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    2001-07-01

    MR digital subtraction angiography (MR DSA), which is performed by a rapid two-dimensional T1-weighted sequence in combination with bolus injection of gadolinium-based contrast agent was applied to the evaluation of cerebral arteriovenous malformations (AVMs), brain tumors (intraaxial and extraaxial tumors), and other vascular lesions. This study was performed to evaluate the clinical usefulness of the method in the diagnosis of these lesions. We studied 19 cases of cerebral AVM, 36 cases of intraaxial tumor (metastatic brain tumors in 14, glioblastomas in five, astrocytomas in eight, malignant lymphomas in four, pineal tumors in two, and other tumors, in three), 34 cases of extraaxial tumor (meningiomas in 29, and pituitary adenomas in five), and 10 cases of other vascular lesions (cerebral aneurysms in five, venous thrombosis in two, and other lesion in three). For cerebral AVMs, the feeder, nidus, and drainer were evaluated on a 4 - point grading scale (0=poor, 1=fair, 2=good, 3=excellent), and the results obtained were compared with those of conventional cerebral angiography or MR angiography using the postcontrast three-dimensional time-of-flight method. Brain tumors were classified into six enhancement patterns, and were compared with the findings of conventional cerebral angiography. Other vascular lesions were assessed visually. All cases were evaluated independently by two radiologists, and inter-observer agreement was assessed using the {kappa}-test. In all cerebral AVM cases, the hemodynamics of the feeder, nidus, and drainer could be observed. In all but five brain tumor cases, tumor stain could be confirmed in MR DSA images. The findings of tumor stain corresponded to those of cerebral angiographic images. For other vascular lesions, results of lesion detection and lesion morphology were almost in congruence with other methods. MR DSA provides information on the hemodynamics of vascular and tumorous lesions. When used in conjunction with routine MR

  4. Transit-time flow measurement as a predictor of coronary bypass graft failure at one year angiographic follow-up

    DEFF Research Database (Denmark)

    Lehnert, Per; Møller, Christian H; Damgaard, Sune;

    2015-01-01

    forty-five CABG patients with intraoperative graft flow measurements and one year angiographic follow-up were analyzed. Graft failure was defined as more than 50% stenosis including the "string sign." Logistic regression analysis was used to analyze the risk of graft failure after one year based on...... graft vessel type, anastomatic configuration, and coronary artery size. RESULTS: Nine hundred eighty-two coronary anastomoses were performed of which 12% had signs of graft failure at one year angiographic follow-up. In internal mammary arteries (IMAs), analysis showed a 4% decrease in graft failure...... odds for every 1 mL/min increase in TTFM (OR = 0.96, CI = [0.93; 0.99], p = 0.005). ROC analysis showed good discriminative ability for TTFM alone AUC = 69.5% in IMA grafts. For single-vein grafts the decrease in graft failure odds was 2% for every 1 mL/min increase in TTFM (OR = 0.98; CI = [0.97; 1...

  5. Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

    Directory of Open Access Journals (Sweden)

    Varga Albert

    2011-06-01

    Full Text Available Abstract Background the clinical decision making could be difficult in patients with borderline lesions (visually assessed stenosis severity of 30 to 50% of the left main coronary artery (LM. The aim of the study was to evaluate the relationship between transthoracic Doppler (TTDE peak diastolic flow velocity (PDV and intravascular ultrasound (IVUS measurements in the assessment of angiographically borderline LM lesions. Methods 27 patients (mean age 64 ± 8 years, 21 males with borderline LM stenosis referred for IVUS examination were included in the study. We performed standard IVUS with minimal lumen area (MLA and plaque burden (PB measurement and routine quantitative coronary angiography (QCA with diameter stenosis (%DS and area stenosis (%AS assessment in all. During TTDE, resting PDV was measured in the LM. Results interpretable Doppler signal could be obtained in 24 patients (88% feasibility; therefore these patients entered the final analysis. MLA was 7.1 ± 2.7 mm2. TTDE measured PDV correlated significantly with IVUS-derived MLA (r = -0.46, p 2 LM stenosis. Conclusion In angiographically borderline LM disease, resting PDV from transthoracic echocardiography is increased in presence of increased plaque burden by IVUS. TTDE evaluation might be a useful adjunct to other invasive and non-invasive methods in the assessment of borderline LM lesions. Further, large scale studies are needed to establish the exact cut-off value of PDV for routine clinical application.

  6. Abdominal Vascular Catastrophes.

    Science.gov (United States)

    Singh, Manpreet; Koyfman, Alex; Martinez, Joseph P

    2016-05-01

    Abdominal vascular catastrophes are among the most challenging and time sensitive for emergency practitioners to recognize. Mesenteric ischemia remains a highly lethal entity for which the history and physical examination can be misleading. Laboratory tests are often unhelpful, and appropriate imaging must be quickly obtained. A multidisciplinary approach is required to have a positive impact on mortality rates. Ruptured abdominal aortic aneurysm likewise may present in a cryptic fashion. A specific type of ruptured aneurysm, the aortoenteric fistula, often masquerades as the more common routine gastrointestinal bleed. The astute clinician recognizes that this is a more lethal variant of gastrointestinal hemorrhage. PMID:27133247

  7. Microfluidic Technology in Vascular Research

    Directory of Open Access Journals (Sweden)

    A. D. van der Meer

    2009-01-01

    Full Text Available Vascular cell biology is an area of research with great biomedical relevance. Vascular dysfunction is involved in major diseases such as atherosclerosis, diabetes, and cancer. However, when studying vascular cell biology in the laboratory, it is difficult to mimic the dynamic, three-dimensional microenvironment that is found in vivo. Microfluidic technology offers unique possibilities to overcome this difficulty. In this review, an overview of the recent applications of microfluidic technology in the field of vascular biological research will be given. Examples of how microfluidics can be used to generate shear stresses, growth factor gradients, cocultures, and migration assays will be provided. The use of microfluidic devices in studying three-dimensional models of vascular tissue will be discussed. It is concluded that microfluidic technology offers great possibilities to systematically study vascular cell biology with setups that more closely mimic the in vivo situation than those that are generated with conventional methods.

  8. Occult infarct with acute hemorrhagic stroke in juvenile diabetic ketoacidosis.

    Science.gov (United States)

    Lin, Jainn-Jim; Lin, Kuang-Lin; Wang, Huei-Shyong; Wong, Alex Mun-Ching; Hsia, Shao-Hsuan

    2008-01-01

    Diabetes ketoacidosis (DKA) is one of the common complications of type I insulin-dependent diabetes mellitus. Neurological deterioration during an episode of DKA is usually assumed to be caused by cerebral edema and cerebral vascular accidents. However, hemorrhagic stroke is a very rare complication of juvenile DKA. We describe a girl who had newly diagnosed insulin-dependent diabetes mellitus with juvenile DKA developed intracerebral hemorrhage. PMID:17629647

  9. Occult hepatitis B virus infection: A complex entity with relevant clinical implications

    Institute of Scientific and Technical Information of China (English)

    Juan Ramon Larrubia

    2011-01-01

    Occult hepatitis B virus (HBV) infection is a world-wide entity, following the geographical distribution of detectable hepatitis B. This entity is defined as the persistence of viral genomes in the liver tissue and in some instances also in the serum, associated to negative HBV surface antigen serology. The molecular basis of the occult infection is related to the life cycle of HBV, which produces a covalently closed circular DNA that persists in the cell nuclei as an episome, and serves as a template for gene transcription. The mechanism responsible for the HBsAg negative status in occult HBV carriers is a strong suppression of viral replication, probably due to the host's immune response, co-infection with other infectious agents and epigenetic factors. There is emerging evidence of the potential clinical relevance of occult HBV infection, since this could be involved in occult HBV transmission through orthotopic liver transplant and blood transfusion, reactivation of HBV infection during immunosuppression, impairing chronic liver disease outcome and acting as a risk factor for hepatocellular carcinoma. Therefore it is important to bear in mind this entity in cryptogenetic liver diseases, hepatitis C virus/HIV infected patients and immunosupressed individuals.It is also necessary to increase our knowledge in this fascinating field to define better strategies to diagnose and treat this infection.

  10. Characteristics of occult hepatitis B virus infection in the Solomon Islands.

    Science.gov (United States)

    Utsumi, Takako; Yano, Yoshihiko; Truong, Bui Xuan; Kawabata, Masato; Hayashi, Yoshitake

    2011-06-01

    Hepatitis B virus (HBV) infection is highly endemic in the Solomon Islands. However, little is known about the status of occult HBV infection in the Solomon Islands. This study aimed to investigate the prevalence of occult HBV infection and its clinical and virological features in the community of Solomon Islands. Blood samples were collected from a total of 564 asymptomatic individuals aged over 18 years in the Western province. The samples used in the present study consisted of 200 samples from 108 males and 92 females (mean age, 37.4 years; range, 18-71 years) that were randomly selected among the hepatitis B surface antigen (HBsAg)-negative samples from all the participants enrolled in this study. HBV-DNA was detected by real-time PCR in 25 (12.5%) of the 200 HBsAg-negative samples. Most of the HBV-DNA-positive individuals were infected with wild-type HBV, and only 3 strains demonstrated specific amino acid substitutions (P121X, T123N, C138S, P142S and D144E) in the α determinant region. In conclusion, occult HBV infection was documented in 12.5% of individuals that demonstrated serologic evidence of resolved HBV infection in this study. The prevalence of occult infection was also influenced by ethnicity; it was more prevalent in Melanesians than Micronesians. In addition, occult HBV infection demonstrated a weak association with the S-variants. PMID:21455562

  11. Using the EXIST Active Shields for Earth Occultation Observations of X-Ray Sources

    Science.gov (United States)

    Wilson, Colleen A.; Fishman, Gerald; Hong, Jae-Sub; Gridlay, Jonathan; Krawczynski, Henric

    2005-01-01

    The EXIST active shields, now being planned for the main detectors of the coded aperture telescope, will have approximately 15 times the area of the BATSE detectors; and they will have a good geometry on the spacecraft for viewing both the leading and training Earth's limb for occultation observations. These occultation observations will complement the imaging observations of EXIST and can extend them to higher energies. Earth occultatio observations of the hard X-ray sky with BATSE on the Compton Gamma Ray Observatory developed and demonstrated the capabilities of large, flat, uncollimated detectors for this method. With BATSE, a catalog of 179 X-ray sources was monitored twice every spacecraft orbit for 9 years at energies above about 25 keV, resulting in 83 definite detections and 36 possible detections with 5-sigma detection sensitivities of 3.5-20 mcrab (20-430 keV) depending on the sky location. This catalog included four transients discovered with this technique and many variable objects (galactic and extragalactic). This poster will describe the Earth occultation technique, summarize the BATSE occultation observations, and compare the basic observational parameters of the occultation detector elements of BATSE and EXIST.

  12. Risk factors predictive of occult cancer detection in patients with unprovoked venous thromboembolism

    Science.gov (United States)

    Ihaddadene, Ryma; Corsi, Daniel J.; Lazo-Langner, Alejandro; Shivakumar, Sudeep; Zarychanski, Ryan; Tagalakis, Vicky; Solymoss, Susan; Routhier, Nathalie; Douketis, James; Le Gal, Gregoire

    2016-01-01

    Risk factors predictive of occult cancer detection in patients with a first unprovoked symptomatic venous thromboembolism (VTE) are unknown. Cox proportional hazard models and multivariate analyses were performed to assess the effect of specific risk factors on occult cancer detection within 1 year of a diagnosis of unprovoked VTE in patients randomized in the Screening for Occult Malignancy in Patients with Idiopathic Venous Thromboembolism (SOME) trial. A total of 33 (3.9%; 95% CI, 2.8%-5.4%) out of the 854 included patients received a new diagnosis of cancer at 1-year follow-up. Age ≥ 60 years (hazard ratio [HR], 3.11; 95% CI, 1.41-6.89; P = .005), previous provoked VTE (HR, 3.20; 95% CI, 1.19-8.62; P = .022), and current smoker status (HR, 2.80; 95% CI, 1.24-6.33; P = .014) were associated with occult cancer detection. Age, prior provoked VTE, and smoking status may be important predictors of occult cancer detection in patients with first unprovoked VTE. This trial was registered at www.clinicaltrials.gov as #NCT00773448. PMID:26817957

  13. Persistent occult hepatitis B virus infection: Experimental findings and clinical implications

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hepatitis B virus (HBV) is a highly pathogenic virus that causes chronic liver diseases in millions of people globally. In addition to a symptomatic, serologically evident infection, occult persistent HBV carriage has been identified since nucleic acid amplification assays of enhanced sensitivity became introduced for detection of hepadnaviral genomes and their replicative intermediates. Current evidence indicates that occult HBV infection is a common and long-term consequence of resolution of acute hepatitis B. This form of residual infection is termed as secondary occult infection (SOI).The data from the woodchuck model of HBV infection indicate that exposure to small amounts of hepadnavirus can also cause primary occult infection (POI) where virus genome, but no serological makers of exposure to virus, are detectable, and the liver may not be involved.However, virus replicates at low levels in the lymphatic system in both these forms. We briefly summarize the current understanding of the nature and characteristics of occult hepadnaviral persistence as well as of its documented and expected pathological consequences.

  14. Occult hepatitis B virus infection in liver transplant patients in a Brazilian referral center

    Directory of Open Access Journals (Sweden)

    T.C.A. Ferrari

    2014-11-01

    Full Text Available Estimates of occult hepatitis B virus (HBV infection prevalence varies among different studies depending on the prevalence of HBV infection in the study population and on the sensitivity of the assay used to detect HBV DNA. We investigated the prevalence of occult HBV infection in cirrhotic patients undergoing liver transplantation in a Brazilian referral center. Frozen liver samples from 68 adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The specificity of the amplified HBV sequences was confirmed by direct sequencing of the amplicons. The patient population comprised 49 (72.1% males and 19 (27.9% females with a median age of 53 years (range=18-67 years. Occult HBV infection was diagnosed in three (4.4% patients. The etiologies of the underlying chronic liver disease in these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers of previous HBV infection were available in two patients with occult HBV infection and were negative in both. In conclusion, using a sensitive nested polymerase chain reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of occult HBV infection in cirrhotic patients undergoing liver transplant, probably due to the low prevalence of HBV infection in our population.

  15. Evaluation of the incidence of occult bacteremia among children with fever of unknown origin

    Directory of Open Access Journals (Sweden)

    Eitan Naaman Berezin

    2006-12-01

    Full Text Available We reviewed the incidence of occult bacteremia, to identify the most frequent etiological agents of bacteremias in otherwise healthy children from one month to 10 years old, who had fever of unknown origin attended at the emergency ward of an urban, university-affiliated pediatric referral center. This was a retrospective medical record review, evaluating children with fever. Data were collected from the initial visit, when blood cultures, hematological properties and hemosedimentation rates were examined. Fever was considered as the highest temperature assessed in the hospital or reported by the responsible adult. Occult bacteremia was discovered in 1.4% of the 1,051 children evaluated, and the most common etiologic agent was Streptococcus pneumoniae. Total leukocyte count and blood sedimentation rates greater than 30 mm³ were not predictive factors for occult bacteremia. Fever greater than 39ºC was the most important factor for predicting occult bacteremia (P<0.001. The presence of occult bacteremia was significantly correlated with patient hospitalization.

  16. Outcome of Concurrent Occult Hemothorax and Pneumothorax in Trauma Patients Who Required Assisted Ventilation

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    Ismail Mahmood

    2015-01-01

    Full Text Available Background. The management and outcomes of occult hemopneumothorax in blunt trauma patients who required mechanical ventilation are not well studied. We aimed to study patients with occult hemopneumothorax on mechanical ventilation who could be carefully managed without tube thoracostomy. Methods. Chest trauma patients with occult hemopneumothorax who were on mechanical ventilation were prospectively evaluated. The presence of hemopneumothorax was confirmed by CT scanning. Hospital length of stay, complications, and outcome were recorded. Results. A total of 56 chest trauma patients with occult hemopneumothorax who were on ventilatory support were included with a mean age of 36 ± 13 years. Hemopneumothorax was managed conservatively in 72% cases and 28% underwent tube thoracostomy as indicated. 29% of patients developed pneumonia, 16% had Acute Respiratory Distress Syndrome (ARDS, and 7% died. Thickness of hemothorax, duration of mechanical ventilation, and development of ARDS were significantly associated with tube thoracostomy in comparison to no-chest tube group. Conclusions. The majority of occult hemopneumothorax can be carefully managed without tube thoracostomy in patients who required positive pressure ventilation. Tube thoracotomy could be restricted to those who had evidence of increase in the size of the hemothorax or pneumothorax on follow-up chest radiographs or developed respiratory compromise.

  17. Significance of the occulter diffraction for the PROBA3/ASPIICS formation flight metrology

    Science.gov (United States)

    Landini, Federico; Bemporad, Alessandro; Focardi, Mauro; Fineschi, Silvano; Romoli, Marco; Pancrazzi, Maurizio; Baccani, Cristian; Capobianco, Gerardo; Loreggia, Davide; Nicolini, Gianalfredo; Massone, Giuseppe; Noce, Vladimiro; Thizy, Cédric; Servaye, Jean-Sébastien; Renotte, Etienne

    2015-09-01

    PROBA-3/ASPIICS is a formation flying coronagraph selected by ESA and currently in its C/D phase. It is constituted by two spacecrafts (OSC, Occulter SpaceCraft, carrying the occulter, diameter 142 cm, and CSC, Coronagraph SpaceCraft, with the telescope) separated by ~144 m, kept in strict alignment by means of an active custom system. The alignment active system most critical components are the Shadow Positioning Sensors (SPS), a series of Si-PM (Silicon Photomultiplier) measuring the penumbra generated by the occulter. The arrangement of the SPSs around the telescope entrance aperture is defined as a trade-off between mechanical constraints and maximum sensitivity to misalignments. The signal detected by the SPSs can be approximately simulated with a geometrical analysis based on the variation of the penumbra generated by the external occulter. The stray light generated by the diffraction from the external occulter may affect the SPSs signal. It is mandatory to carefully evaluate its level in order to refine the active alignment adjustment algorithm. This work is dedicated to the description of the preliminary investigation performed in order to evaluate the impact of the diffraction on the SPSs signal.

  18. MRI evaluation of vascular dementia

    Institute of Scientific and Technical Information of China (English)

    Yicheng Liu; Hongxing Zhang; Wei Huang; Wenjun Wan; Hongfen Peng

    2006-01-01

    OBJECTTVE: To explain the association between vascular dementia and the cranial MRI manifestations, and recognize the value of cranial MRI in the early diagnosis of vascular dementia and the assessment of disease conditions.DATA SOURCES: Pubmed database was searched to identify articles about the cranial MRI manifestations of patients with vascular dementia published in English from January 1992 to June 2006 by using the key words of "MRI, vascular dementia". Others were collected by searching the name of journals and title of articles in the Chinese full-text journal database.STUDY SELECTTON: The collected articles were primarily checked, those correlated with the cranial MRI manifestations of patients with vascular dementia were selected, while the obviously irrelative ones were excluded, and the rest were retrieved manually, the full-texts were searched.DATA EXTRACTION: Totally 255 articles were collected, 41 of them were involved, and the other 214 were excluded.DATA SYNTHESIS: MRI can be taken as one of the effective methods for the early diagnosis and disease evaluation of vascular dementia. White matter lesions are the important risk factors of vascular dementia.Vascular dementia is accompanied by the atrophy of related brain sites, but further confirmation is needed to investigate whether there is significant difference. MRI can be used to quantitatively investigate the infarcted sites and sizes of patients with vascular dementia after infarction, but there is still lack of systematic investigation on the association of the infarcted sites and sizes with the cognitive function of patients with vascular dementia.CONCLUSTON: Cranial MRI can detect the symptoms of vascular dementia at early period, so that corresponding measures can be adopted to prevent and treat vascular dementia in time.

  19. Vascular Remodeling in Experimental Hypertension

    Directory of Open Access Journals (Sweden)

    Norma R. Risler

    2005-01-01

    Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

  20. Spinal vascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Krings, Timo [University Hospital Aachen, Department of Neuroradiology, Aachen (Germany); University Hospital Aachen, Department of Neurosurgery, Aachen (Germany); Mull, Michael; Thron, Armin [University Hospital Aachen, Department of Neuroradiology, Aachen (Germany); Gilsbach, Joachim M. [University Hospital Aachen, Department of Neurosurgery, Aachen (Germany)

    2005-02-01

    Spinal vascular malformations are rare diseases that consist of true inborn cavernomas and arteriovenous malformations (including perimedullary fistulae, glomerular and juvenile AVMs) and presumably acquired dural arteriovenous fistulae. This review article gives an overview of the imaging features both on MRI and angiography, the differential diagnoses, the clinical symptomatology and the potential therapeutic approaches to these diseases. It is concluded that MRI is the diagnostic modality of first choice in suspected spinal vascular malformation and should be complemented by selective spinal angiography. Treatment in symptomatic patients offers an improvement in the prognosis, but should be performed in specialized centers. Patients with spinal cord cavernomas and perimedullary fistulae type I are surgical candidates. Dural arteriovenous fistulae can either be operated upon or can be treated by an endovascular approach, the former being a simple, quick and secure approach to obliterate the fistula, while the latter is technically demanding. In spinal arteriovenous malformations, the endovascular approach is the method of first choice; in selected cases, a combined therapy might be sensible. (orig.)