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Sample records for 99-technetium sestamibi scanning

  1. Bone metastasis on Tc99-m sestamibi myocardial perfusion scan

    PubMed Central

    Hatemi, Lachin; Jabi, Feraas

    2015-01-01

    A 75-year-old woman presented to our department for a stress myocardial perfusion imaging study with Tc99m-sestamibi. Incidental focal uptake, found in the left upper anterior chest, was initially felt to be located in the left breast. After additional single-photon CT imaging was performed the same day, extracardiac foci within the ribs, spine, and left lung (worrisome for active metastases) were shown to be present, with the initial focus located within a left rib rather than a breast. A review of previous radiographic and nuclear imaging studies confirmed metastatic disease from recurrent follicular thyroid cancer. Atypical focal extracardiac activity must be closely scrutinized for the possibility of malignancy, as Tc99m-sestamibi (in addition to being myocardium-avid) is tumor-avid.

  2. Pretest probability assessment for selective rest sestamibi scans in stable chest pain patients.

    PubMed

    Welch, R D; Zalenski, R J; Shamsa, F; Waselewsky, D R; Kosnik, J W; Compton, S

    2000-11-01

    The objective of this study was to determine whether pretest probability assessments permit more selective testing of chest pain patients with technetium-99m sestamibi scanning. Pretest probabilities of cardiac ischemia were measured both objectively (Acute Cardiac Ischemia Time-Insensitive Predictive Instrument [ACI-TIPI]) and subjectively (physician's estimate of the probability of unstable angina). Two groups were defined: patients whose postsestamibi scan led to a "downgrade" of the intensity of monitoring and those that resulted in no change in monitoring intensity. Sixty-five patients met study criteria; 25 had a disposition downgrade and 40 had no change. Pretest ACI-TIPI scores were similar in the two groups (29% +/- 18% versus 27% +/- 11%, mean +/- standard deviation; P = .95) as were the physician's assessment of unstable angina (39% +/- 22% versus 40% +/- 24%; P = .75). Objective or subjective pretest probabilities are not significantly different in patients who are likely to have their disposition altered by sestamibi scanning. PMID:11103730

  3. 99mTc Sestamibi Thyroid Scan in Amiodarone-Induced Thyrotoxicosis Type I.

    PubMed

    Patel, Niraj R; Tamara, Luis A; Lee, Ho

    2016-07-01

    Amiodarone-induced thyrotoxicosis (AIT) type I describes inducement of clinical hyperthyroidism by excessive thyroidal iodine in the setting of latent Graves disease, and therapy differs from that used for AIT type II. A 65-year-old man previously on amiodarone for atrial fibrillation developed clinical hyperthyroidism. Diagnosis of AIT was made, but the type was not clear. Tc sestamibi thyroid scan showed diffusely increased uptake and retention in an enlarged thyroid gland, a pattern consistent with AIT type I. Methimazole was initiated and controlled the thyrotoxicosis. I iodide thyroid scan and uptake study performed later was consistent with Graves disease. PMID:27163459

  4. Sestamibi (99mTc) scan as a single localization modality in primary hyperparathyroidism and factors impacting its accuracy

    PubMed Central

    Alabdulkarim, Yousof; Nassif, Edgard

    2010-01-01

    Background The proper localization of a hypersecreting parathyroid gland is of vital importance for successful unilateral neck exploration (UNE) and parathyroidectomy. Aim: In this study we aim to evaluate the (99mTc) sestamibi parathyroid scan as a single localizing modality, and we also assess its relation to the weight of the gland and to the preoperative parathyroid hormone (PTH) levels. Patients and Methods: We reviewed 170 patients from our hospital (Notre-Dame hospital) from 2005 to 2008, with a mean age of 56.6 years and a female to male ratio of 3.3:1. With primary hyperparathyroidism, all of them had (99mTc) sestamibi parathyroid scan for the localization of the parathyroid adenoma. Preoperative and postoperative PTH levels were recorded. The histopathology reports confirmed the diagnosis and weight of the diseased gland, which were recorded every time. The results were analyzed and correlated with the sestamibi results, to evaluate its accuracy. Results: Seventy-eight patients (41%) of the 170 had an exact match (EM) sestamibi results, 81 (51.6%) had a partial match, and only 11 patients were reported as mismatch. Analyzing the mean weight of the gland in each group between matching (EM, PM) versus mismatch resulted in a mean difference of 0.823 g (1.05 and 0.247 g, respectively) P = 0.045. Hyperplasia to adenoma ratio was more in the partial matching group (18.5%) versus the exact matching group (7.6%). Finally the mean PTH level was higher in the EM group (28.8 pmol/L) compared to the mismatch group (10.1 pmol/L) P = 0.02. Overall sensitivity and specificity for the (99 mTc) sestamibi in our data was 98.1 and 97%, respectively. Conclusion: (99mTc) sestamibi is a highly accurate test that can be employed as a single localizing modality for identifying a hypersecreting parathyroid, a UNE, or a parathyroidectomy. The weight of the gland plays an important role in the accuracy of the test, as also the preoperative PTH levels. PMID:20844661

  5. 99mTechnetium Sestamibi-123Iodine Scintigraphy Is More Accurate Than 99mTechnetium Sestamibi Alone before Surgery for Primary Hyperparathyroidism

    PubMed Central

    Ryhänen, Eeva M.; Schildt, Jukka; Heiskanen, Ilkka; Väisänen, Mika; Ahonen, Aapo; Löyttyniemi, Eliisa; Schalin-Jäntti, Camilla; Välimäki, Matti J.

    2015-01-01

    Objectives. Studies comparing outcome of single-99mTc-methoxyisobutylisonitrile (99mTc-sestamibi) and dual-tracer 99mTc-sestamibi scintigraphy in combination with 123I before primary surgery of primary hyperparathyroidism (PHPT) are scarce. Methods. We compared 99mTc-sestamibi/123I and 99mTc-sestamibi in a single-centre retrospective series of 269 PHPT patients. The results were related to laboratory, surgical and histological findings. Results. 99mTc-sestamibi/123I and 99mTc-sestamibi were positive in 206 (76.6%) and 111 (41.3%) of 269 patients, respectively (P < 0.001). Accuracies for 99mTc-sestamibi/123I and 99mTc-sestamibi were 63.4% and 34.9%, respectively (96% CI, P < 0.001). Prevalence of multiglandular disease was 15.2%. In multiglandular disease, 99mTc-sestamibi/123I and 99mTc-sestamibi revealed 43.8 and 22.1% of pathological glands, respectively (P < 0.001). Cure rate was similar for patients with (191/206; 92.7%) and without (59 of 63; 93.7%) a positive 99mTc-sestamibi/123I finding. Duration of targeted surgery (one or two quadrants) was 21 and 15 minutes shorter than bilateral neck exploration, respectively (both P < 0.001). Higher serum calcium (P = 0.014) and PTH (P = 0.055) concentrations and larger tumours (P < 0.001) characterized the 206 patients with a positive preoperative scan who were cured by removal of a single adenoma. Conclusions. 99mTc-sestamibi/123I scintigraphy is more accurate than 99mTc-sestamibi before surgery of PHPT. However, outcome of surgery is not determined by scintigraphy alone. PMID:25722888

  6. Decreased Tc-99m sestamibi uptake in a sternal brown tumor indicating response to anti metabolic therapy for secondary hyperparathyroidism.

    PubMed

    Ozkan, Elgin; Arslan, Nuri; Arslanoglu, Atilla; Karacalioglu, Alper Ozgur

    2007-08-01

    Brown tumors are rare but serious complications of renal osteodystrophy, and can be treated by parathyroidectomy or by pharmacological treatment of hyperparathyroidism. In addition to parathyroid lesions such as adenoma, hyperplasia, and carcinoma, brown tumors have been detected effectively by using dual phase Tc-99m sestamibi and Tl-201 chloride. We describe an unusual case of brown tumor at the manibrium sterni which shows marked increased Tc-99m sestamibi uptake on the initial scan, with decreasing tracer activity on follow-up scan indicating a response to antimetabolic therapy. PMID:17667448

  7. Complete improvement in a patient with multiple irreversible defects of the left ventricle on 99m technetium-sestamibi SPECT after percutaneous coronary intervention.

    PubMed

    Javadi, H; Porpiranfar, M A; Semnani, S; Jallalat, S; Yavari, P; Mogharrabi, M; Hooman, A; Amini, A; Barekat, M; Iranpour, D; Assadi, M; Asli, I N

    2012-10-01

    99mTc-sestamibi has been investigated as a potential viability marker; initial studies have shown good concordance between 201Tl and 99mTc-sestamibi activities in both viable and nonviable myocardium. However, assessment of myocardial viability by 99mTc-sestamibi remains controversial for tissue recovery after revascularization. Here, we present a patient with several regions of severely diminished and irreversible (defect persisting in both early and delay images of each set scanning) defects on initial scan which were dissolved completely on the follow up scan after an intervention. In a 75 year-old Asian woman with acute myocardial infarction who received thrombolytic therapy and subjected to percutaneous coronary angiography (PCI) on day 28 after acute myocardial infarction(MI), resting 99mTc-sestamibi SPECT was applied on day 4 (initial scan) and 138 (follow up scan) after acute MI at 30 and 180 min after injection of tracer (740 MBq); Two-dimensional echocardiography was carried out at the same time. On the initial image set, there was irreversible defects in the apex, anteroapical, inferoapical, anteroseptal, septal and also anterior walls, while the follow up image was normal in all regions.The angiography intervention showed just significant stenosis on left anterior descending (LAD) vessel (95%). This may highlight the failure of 99mTc-sestamibi as a marker of myocardial viability and also mandate further validating of the procedure with follow up scan or other modalities for myocardial viability investigation. PMID:23090825

  8. SCAN+

    SciTech Connect

    Kenneth Krebs, John Svoboda

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determine the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.

  9. SCAN+

    Energy Science and Technology Software Center (ESTSC)

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determinemore » the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.« less

  10. Use of pre-operative Tc99m-Sestamibi scintigraphy and intraoperative parathyroid hormone monitoring to eliminate neck exploration in mediastinal parathyroid adenocarcinoma.

    PubMed

    Damadi, Amir; Harkema, James; Kareti, Rao; Saxe, Andrew

    2007-01-01

    A 66-year-old white woman was found to have an elevated serum calcium and parathyroid hormone (PTH) on routine health evaluation. Physical examination was unremarkable as was ultrasonography of the neck. A sestamibi parathyroid scan revealed abnormal uptake in the anterior mediastinum. Computed tomography of the chest demonstrated an anterior mediastinal mass compatible with a parathyroid adenoma but no neck masses. The patient underwent mediastinoscopy that was converted to a median sternotomy to fully access the mass. The mass was completely resected with surrounding thymus gland. Frozen section confirmed that excised tissue was parathyroid gland in origin. An intraoperative PTH obtained 20 minutes after specimen removal showed a decrease of more than 50% from preoperative levels. The strategy for initial surgery for hyperparathyroidism when a sestamibi scan is "positive" in the mediastinum (only) is a point of some controversy. Traditional recommendations have been to "clear the neck" of abnormal parathyroid tissue before undertaking a more morbid sternotomy. Mediastinoscopy was attempted to remove the mediastinal lesion and to avoid a sternotomy. Preoperative Tc99m sestamibi scintigraphy, frozen section histology, and intraoperative PTH monitoring permitted the authors to conclude that neck exploration was unnecessary. PMID:17462212

  11. Osteosclerotic and osteolytic manifestations of hyperparathyroidism in a case of Tc99m SestaMIBI positive parathyroid adenoma

    PubMed Central

    Das, Kalpa Jyoti; Sehgal, Aditi Khurana; Jaiman, Ashish; Sethi, Ravinder Singh

    2015-01-01

    Primary hyperparathyroidism is the first differential diagnosis when a patient presents with asymptomatic hypercalcemia. The symptoms of hyperparathyroidism can be as grave as skeletal, cardiovascular, and neuropsychological changes. Skeletal manifestations are relatively common, and patient may present with generalized or focal bone pains, fragility fractures, subperiosteal bone resorption, and osteolytic lesions like brown tumors and salt and pepper appearance of the skull. However, focal osteosclerotic lesions of the skull are rare findings in hyperparathyroidism. Only a few cases of associated osteosclerosis are reported in the literature. Here, we report a case of Tc99m SestaMIBI positive parathyroid adenoma with coexisting osteolytic and osteosclerotic skull lesions on Tc99m methylene diphosphonate bone scan. PMID:26170573

  12. Technetium-99m sestamibi myocardial imaging: same-day rest-stress studies and dipyridamole.

    PubMed

    Taillefer, R

    1990-10-16

    Unlike thallium-201, technetium-99m (Tc-99m) sestamibi does not redistribute in the myocardium after injection. Thus, 2 separate injections, 1 at rest and the other at stress (or after dipyridamole), are required to differentiate ischemia from scar. From a physical viewpoint, a 24-hour interval between the 2 injections is preferable for detection of coronary artery disease (CAD) with Tc-99m sestamibi imaging. However, same-day studies are more convenient in clinical practice. Results of studies using different Tc-99m sestamibi injection protocols are presented with emphasis on the advantages of a rest-stress injection sequence with a low dose at rest (7 mCi) followed 2 hours later by a higher dose at stress (25 mCi). A prospective study was conducted in a patient population with proven CAD using same-day studies to compare a rest-stress (7 and 25 mCi, respectively) to a stress-rest (7 and 25 mCi) Tc-99m sestamibi injection sequence. There was an agreement in 87.3% of the analyzed segments between the 2 protocols. However, the largest discordance for type of defect applied to 7.4% of the segments judged ischemic in the rest-stress protocol, which were called scars on stress-rest. This study showed that a rest-stress sequence is preferable when using a same-day protocol with a short time interval (less than 2 hours) between the 2 Tc-99m sestamibi injections because the rest image performed initially represents a "true" rest study, which is not necessarily the case with the stress-rest sequence. Preliminary studies were performed to evaluate dipyridamole with Tc-99m sestamibi imaging in normal subjects and in patients with CAD. These studies showed that treadmill and dipyridamole Tc-99m sestamibi imaging are comparable and the results are similar to those obtained with thallium-201. PMID:2145751

  13. Acute myocardial imaging with TC-99m sestamibi identifies the culprit coronary artery in the emergency room assessment of patients with chest pain

    SciTech Connect

    Stowers, S.A.; Thompson, R.C.; Fulmer, H.

    1994-05-01

    Acute myocardial perfusion scintigraphy significantly increases diagnostic accuracy and provides independent predictive information in emergency room (ER) patients with typical angina and a normal or non-diagnostic ECG. We evaluated the correlation between location of perfusion defect on the acute nuclear perfusion scan and location of coronary arterial narrowing demonstrated by pre-hospital discharge coronary angiography. ER patients (n=150) with typical angina and a normal or non-diagnostic ECG had 10-30 mCi of Tc-99m Sestamibi injected while acutely symptomatic. 11 patients with a normal scan and 33 patients with an abnormal scan (total n=44) underwent pre-hospital discharge coronary angiography. Overall diagnostic accuracy in the detection of any significant ({ge}70%) angiographic stenosis was high (84%, p=.001). The diagnostic accuracy of anterior, lateral, and inferior perfusion abnormalities in the detection of significant stenosis of the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA), respectively was determined.

  14. Ectopic Intrathymic Parathyroid adenoma demonstrated on Tc-99m Sestamibi SPECT-CT.

    PubMed

    Usmani, S; Oteifa, M; Abu Huda, F; Javaid, A; Amanguno, H G; Al Kandari, F

    2016-05-01

    Intrathymic parathyroid adenoma is a rare cause of primary hyperparathyroidism. In this case, Tc-99m Sestamibi SPECT-CT successfully localized abnormal tracer uptake in the mediastinum with corresponding low density lesion on CT images suggestive of mediastinal parathyroid adenoma which late on confirmed on histopathology. After the median sternotomy a large intrathymic parathyroid adenoma was identified and excised. With the help of gamma probe the surgeons detect the lesion early and with more confidence as well as reducing the total operation time. Tc-99m Sestamibi SPECT-CT scintigraphy and gamma probe localization is recommended for preoperative and intra operative localization of ectopic parathyroid adenomas. PMID:27250890

  15. 18F-Fluorocholine PET–CT enables minimal invasive parathyroidectomy in patients with negative sestamibi SPECT–CT and ultrasound: A case report

    PubMed Central

    Kluijfhout, Wouter P.; Vriens, Menno R.; Valk, Gerlof D.; Barth, Roos E.; Borel Rinkes, Inne H.M.; de Keizer, Bart

    2015-01-01

    Introduction Primary hyperparathyroidism is a common endocrine disorder for which the primary treatment is surgery. For minimal invasive parathyroidectomy adequate pre-operative imaging is essential. Conventional imaging is often inconclusive. There are reports that 18F-fluorocholine PET–CT might be a superior imaging modality, however evidence is still very scarce. This is the first report of a case with negative ultrasound and sestamibi SPECT–CT imaging that underwent successful minimal invasive surgery because of 18F-fluorocholine PET–CT. Presentation of case A 57 year-old man presented to us with complaints of fatigue. Laboratory results showed a biochemical primary hyperparathyroidism and an additional DEXA-scan revealed osteopenia of the lumbar spine. Conventional imaging consisting of neck ultrasound and Tc-99m-sestamibi SPECT–CT was however unable to localize the pathological gland. Subsequent 18F-fluorocholine PET–CT did clearly localize an adenoma dorsally of the left thyroid lobe which was removed at that exact location using minimal invasive parathyroidectomy. Histological examination confirmed the diagnosis adenoma and calcium levels remained normal at follow-up. Discussion There is clinical need for a superior imaging modality to detect pathological parathyroid glands to enable minimal invasive surgery. 18F-Fluorocholine is widely available. Conclusion 18F-Fluorocholine PET–CT is a promising new imaging modality for localizing parathyroid adenomas and enabling minimal invasive parathyroidectomy when conventional imaging fails to do. Clinicians should consider its use as a second line modality for optimal patient care. PMID:26117451

  16. Normal qualitative and quantitative Tc-99m sestamibi myocardial SPECT: spectrum of intramyocardial distribution during exercise and at rest.

    PubMed

    Lette, J; Caron, M; Cerino, M; McNamara, D; Metayer, S; D'Aoust, S; Eybalin, M C; Levesseur, A; Grégoire, J; Arsenault, A

    1994-04-01

    Exercise myocardial perfusion imaging with Tc-99m sestaMIBI is routinely used to detect underlying coronary stenoses. Ischemia is diagnosed in regions that display decreased tracer uptake during exercise as compared to rest. Tc-99m sestaMIBI SPECT images of 42 healthy volunteers were assessed both qualitatively (tomographic slices) and quantitatively (sectored polar map) for potential sources of misinterpretation. On the myocardial tomographic slices, the most common culprit artifacts were diaphragmatic attenuation and bowel interposition, which caused fixed or reversible "perfusion defects" in the inferior and posterior regions (in 19/35 abnormal segments), and artifacts related to the presence and shift of hot spots (observed in 11/28 men; in women, they were more difficult to demonstrate because of the overriding effect of breast attenuation). Hot spots shifts between exercise and rest usually resulted in pseudo-reversible defects in the anterolateral and lateral walls. The quantified polar map display of the myocardium showed a physiologic decrease in sestaMIBI activity in the basal anterolateral and basal posterolateral areas in men during exercise. There are many normal variants that may mimic coronary artery disease on tomographic sestaMIBI images. Before reporting an area of decreased activity as either a fixed or reversible perfusion defect, the interpreter should ensure that it does not represent an artifact or a normal variation in the intramyocardial distribution of sestaMIBI during exercise. PMID:8004868

  17. Modulation of the multidrug resistance P-glycoprotein: Detection with technetium-99m-sestamibi in vivo

    SciTech Connect

    Luker, G.D.; Fracasso, P.M.; Dobkin, J.; Piwnica-Worms, D.

    1997-03-01

    Overexpression of the multidrug resistance (MDR1) P-glycoprotein (Pgp) has been documented in nearly all forms of human cancers and increased levels of Pgp in some tumors correlate with poor response to treatment. Technetium-99m-sestamibi has recently been validated as a Pgp transport substrate. Pgp is also normally expressed along the biliary canalicular surface of hepatocytes and the luminal side of proximal tubule cells in the kidney, while not expressed in heart. Focused on these organs with known Pgp status, we present the findings on {sup 99m}Tc-sestamibi showed normal, prompt clearance of the radiotracer from the liver and kidneys relative to the heart. After administration of the Pgp modulator, {sup 99m}Tc-sestamibi was selectively retained in the liver and kidneys. Hepatobiliary and renal clearance of {sup 99m}Tc-sestamibi are Pgp-mediated, and inhibition of Pgp transport in these organs can be successfully imaged using {sup 99m}Tc-sestamibi in patients. Similar results might be expected with this and related radiopharmaceuticals for functional imaging of Pgp transport and modulation in tumors. 34 refs., 2 figs.

  18. Comparison of 99mTc-sestamibi and doxorubicin to monitor inhibition of P-glycoprotein function

    PubMed Central

    Muzzammil, T; Moore, M J; Hedley, D; Ballinger, J R

    2001-01-01

    P-glycoprotein (Pgp) overexpression is a well-recognized factor in resistance to chemotherapy. Doxorubicin flow cytometry is used to monitor Pgp function in haematological specimens and biopsies from other cancers, and radionuclide imaging with sestamibi has recently shown promise for non-invasive monitoring. In the present study the two methods were directly compared in single-cell suspensions of three variants of the human breast carcinoma cell line MCF7: sensitive MCF7/WT, doxorubicin-selected MCF7/AdrR, and MDR1 -gene-transfected MCF7/BC19 cells with doxorubicin resistance factors of 1, 192, and 14, respectively. Accumulation of sestamibi and mean fluorescence of doxorubicin (5.5 μM) were assessed over 60 min in the presence and absence of Pgp modulators GG918 (0.01 to 0.2 μM) and PSC833 (0.05 to 2.0 μM). Accumulation curves for sestamibi and doxorubicin differed among the cell variants under control conditions, with sestamibi showing a significantly greater difference between WT and resistant cells than doxorubicin. Both GG918 and PSC833 reversed uptake deficits to WT levels for sestamibi in MCF7/BC19 cells and doxorubicin in MCF7/BC19 and MCF7/AdrR cells, but failed to show the same effect for sestamibi in MCF7/AdrR cells (∼30% of MCF7/WT level). Thus, both methods clearly distinguished sensitive from resistant MCF7 variants, with the radionuclide method showing greater sensitivity. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11161402

  19. Technetium-99m sestamibi in chronic coronary artery disease: The European experience

    SciTech Connect

    Sochor, H. )

    1990-10-16

    Since the introduction of technetium-99m methoxy-isobutyl isonitrile (Tc-99m sestamibi) in Europe, there has been a growing interest in its use. Several European multicenter trials have been conducted to evaluate this new agent in relation to the traditional perfusion marker thallium-201, and other studies are in progress to understand the use of this perfusion marker for the diagnosis of coronary disease, for use in conjunction with pharmacologic vasodilation, for use in the assessment of ventricular function and wall motion and for the assessment of interventions.

  20. Thrombolytic therapy for myocardial infarction: Assessment of efficacy by myocardial perfusion imaging with technetium-99m sestamibi

    SciTech Connect

    Wackers, F.J. )

    1990-10-16

    Technetium-99m (Tc-99m) sestamibi has been used to evaluate the efficacy of thrombolytic therapy. Improved image quality due to the higher photon energy of Tc-99m and the increased allowable doses of this radiopharmaceutical along with its lack of redistribution makes Tc-99m sestamibi an acceptable imaging agent for such studies. This imaging agent was used for serial quantitative planar and tomographic imaging to assess the initial risk area of infarction, its change over time and the relation to infarct-related artery patency in patients with a first acute myocardial infarction. Twenty-three of 30 patients were treated with recombinant tissue-type plasminogen activator (rt-PA) within 4 hours after onset of acute chest pain. Seven patients were treated in the conventional manner and did not receive thrombolytic therapy. The initial area at risk varied greatly both in patients treated with rt-PA and in those who received conventional therapy. Patients with successful thrombolysis and patient infarct arteries had a significantly greater reduction of Tc-99m sestamibi defect size than patients who had persistent coronary occlusion. Serial imaging with Tc-99m sestamibi could find important application in future clinical research evaluating the efficacy of new thrombolytic agents. Direct measurements of the amount of hypoperfused myocardium before and after thrombolysis could provide rapid and unequivocal results using fewer patients and avoiding the use of mortality as an end point. This approach has not yet been widely tested in the clinical arena.

  1. Significance of 99mTc-Sestamibi myocardial scintigraphy after percutaneous coronary intervention in patients with acute myocardial infarction

    PubMed Central

    Akashi, Yoshihiro J.; Ashikaga, Kohei; Takano, Makoto; Izumo, Masaki; Ishibashi, Yuki; Kida, Keisuke; Yoneyama, Kihei; Suzuki, Kengo; Miyake, Fumihiko; Banach, Maciej

    2011-01-01

    Summary Background This study was designed to clarify the significance of washout rate (WR) determined from 99mTc-sestamibi myocardial scintigraphic images and the levels of cardiac enzymes in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). Material/Methods A total of 56 consecutive patients with AMI (mean age 65.8±8.5 years), who underwent PCI on admission, were included. Cardiac enzyme, the MB isoenzyme of creatinine kinase (CK-MB), was measured every 3 h after admission. Two weeks after the onset of AMI, 99mTc-sestamibi myocardial scintigraphy was performed at early (30 min) and delayed (4 h) phases after tracer injection. The heart-to-mediastinum ratio (H/M) and WR were calculated from the planar images. Results PCI was performed at 9.4±6.0 h after the onset of AMI. In 26 patients the culprit lesion was located in the right coronary artery and in 24 patients it was located in the left anterior descending coronary artery. The peak CK-MB was 274.1±169.4 IU/L (13.5±3.9 h). The early and delayed H/Ms and WR of 99mTc-sestamibi were 2.74±0.58, 3.00±0.70, and 58.8±10.0%, respectively. The delayed H/M was significantly correlated with the peak CK-MB (r=−0.37, p=0.005). The WR of 99mTc-sestamibi was also significantly correlated with the peak CK-MB (r=−0.34, p=0.012). Conclusions These results suggest that the WR determined from 99mTc-sestamibi myocardial scintigraphic images reflects the extent of myocardial damage in AMI patients. PMID:21358600

  2. Large abdominal photopenic area on 99mTc-sestamibi myocardial perfusion imaging.

    PubMed

    Lyon, Jennifer; Spaulding, John; Zack, Paul M

    2012-12-01

    (99m)Tc-sestamibi myocardial perfusion imaging is frequently performed in conjunction with exercise or pharmacologic stress testing for evaluation of coronary heart disease. Interpretation of these studies includes systematic review of unprocessed rotating projectional images for evaluation of cardiac size as well as the presence of motion or attenuation artifacts. Occasionally, incidental noncardiac findings are detected on review of the projectional images. We report a case of a patient with a history of autosomal dominant polycystic kidney disease who was found to have a large abdominal photopenic area on the projectional images. The photopenic area corresponded to the location of large intraabdominal cysts on abdominal CT and was consistent with hepatic cysts associated with the patient's known polycystic kidney disease. We review the differential diagnosis of large abdominal photopenic regions identified on myocardial projectional images and the importance of routinely analyzing these images for incidental noncardiac findings. PMID:22997275

  3. The role of preoperative ultrasonography, computed tomography, and sestamibi scintigraphy localization in secondary hyperparathyroidism

    PubMed Central

    Lee, Jae Bok; Kim, Woo Young

    2015-01-01

    Purpose The role of preoperative localization studies is controversial in surgery of secondary hyperparathyroidism (sHPT). The aim of study was to evaluate the accuracy of preoperative ultrasonography (USG), CT, and 99mTc sestamibi scintigraphy (MIBI) in localizing enlarged parathyroid glands and to find the impact of correct localization in successful parathyroidectomy. Methods We compared operative findings with the preoperative localization of ultrasonography, computerized tomography and sestamibi scintigraphy in 109 patients with sHPT and identified well-visualized locations of abnormal parathyroid glands by evaluating the sensitivity of each imaging study with regard to typical locations of glands. We investigated the effect of preoperative imaging localization on the surgical outcomes by measuring the intraoperative parathyroid hormone (ioPTH) decrement for positive or negative imaging localization. Results USG (91.5%) had the highest sensitivity and MIBI (56.1%) had the lowest among 3 modalities. The sensitivity of combined USG and CT (95.0%) was the highest among combined 2 modalities. The combination of all 3 modalities (95.4%) had the highest sensitivity among the combinations of modalities. The reduction of ioPTH in patients with positive imaging localization (86.6%) was greater than negative imaging localization (84.2%), with no significant difference (P = 0.586). The recurrence or persistence of sHPT was not correlated with preoperative imaging localization (19 patients in negative, 16 in positive; P = 0.14). Conclusion Preoperative imaging localization contributed to surgical success but not to surgical outcomes. The combination of ioPTH measurement with imaging localization might be valuable for better surgical results in sHPT. PMID:26665124

  4. Comparison of personnel radiation dosimetry from myocardial perfusion scintigraphy: Technetium-99m-sestamibi versus thallium-201

    SciTech Connect

    Culver, C.M.; Dworkin, H.J. )

    1993-07-01

    The whole-body and hand radiation doses to our technical staff were retrospectively compared for three distinct 4-mo periods when either 201TI or 99mTc-sestamibi were exclusively used for stress myocardial perfusion imaging. During the initial 4-mo period when 99mTc-sestamibi replaced 201TI, the mean whole-body film badge readings increased from 100 to 450 microSv/mo (p < 0.001) for nuclear medicine technologists (n = 10) and from 240 to 560 microSv/mo (p < 0.05) for radiopharmacy technologists (n = 2). Mean TLD readings to the hands also increased, although the differences were not statistically significant for the nuclear medicine technologists. Noninvasive cardiology staff were monitored with film badges and the mean whole-body film badge reading, when 99mTc-sestamibi was the imaging agent, was 360 microSv per month. Radiation reduction methods that decreased radiation exposure to staff were utilized. The most effective included the use of a lead face shield and lead lined storage container in the noninvasive imaging area, handling spills by shielding instead of decontamination and methods to reduce time spent in close proximity to the patient.

  5. Comparison of personnel radiation dosimetry from myocardial perfusion scintigraphy: technetium-99m-sestamibi versus thallium-201.

    PubMed

    Culver, C M; Dworkin, H J

    1993-07-01

    The whole-body and hand radiation doses to our technical staff were retrospectively compared for three distinct 4-mo periods when either 201TI or 99mTc-sestamibi were exclusively used for stress myocardial perfusion imaging. During the initial 4-mo period when 99mTc-sestamibi replaced 201TI, the mean whole-body film badge readings increased from 100 to 450 microSv/mo (p < 0.001) for nuclear medicine technologists (n = 10) and from 240 to 560 microSv/mo (p < 0.05) for radiopharmacy technologists (n = 2). Mean TLD readings to the hands also increased, although the differences were not statistically significant for the nuclear medicine technologists. Noninvasive cardiology staff were monitored with film badges and the mean whole-body film badge reading, when 99mTc-sestamibi was the imaging agent, was 360 microSv per month. Radiation reduction methods that decreased radiation exposure to staff were utilized. The most effective included the use of a lead face shield and lead lined storage container in the noninvasive imaging area, handling spills by shielding instead of decontamination and methods to reduce time spent in close proximity to the patient. PMID:8315504

  6. Scanning, Scanning, Everywhere.

    ERIC Educational Resources Information Center

    Ekhaml, Leticia; Myers, Brenda

    1997-01-01

    Discusses uses of scanning (process of copying or converting text, images, and objects into information that the computer can recognize and manipulate) in schools and notes possible desktop publishing projects. Describes popular scanners and ways to edit a scanned image. A sidebar gives costs and telephone numbers for nine scanners. (AEF)

  7. Feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) 99mTc-sestamibi protocol.

    PubMed

    Rubello, Domenico; Al-Nahhas, Adil; Mariani, Giuliano; Gross, Milton D; Rampin, Lucia; Pelizzo, Maria Rosa

    2006-01-01

    Aim of the present study was to investigate the feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) 99mTc-sestamibi dose protocol compared to conventional "high 740 MBq (20 mCi) 99mTc-sestamibi dose protocol" in patients with primary hyperparathyroidism (PHPT). The data of focused radioguided surgery obtained in a group of 320 consecutive PHPT patients with high probability of the presence of a solitary parathyroid adenoma (PA) were studied. All patients underwent preoperative imaging work-up of double-tracer 99mTc-pertechnetate/99mTc-sestamibi subtraction parathyroid scintigraphy (Sestamibi scintigraphy) and high resolution neck ultrasound (US). In 301/320 patients (96.6%) focused minimally invasive radioguided surgery was successfully performed by administering a "low" 37 MBq (1 mCi) 99mTc-sestamibi dose in the operating room 10 minutes before operation. No major intraoperative complications were recorded. Focused radioguided surgery required a mean time of 32 min and a mean hospital stay of 1.2 days. Local anesthesia was applied in 75 patients, 66 of whom (88%) were patients older than 65 years with comorbidities contraindicating general anesthesia. No case of persistent or recurrent PHPT was observed during post-surgical follow-up (range = 18-70 months; mean +/- SD = 15.3 +/- 9.1 months). Radiation exposure dose to the operating surgeon was 1.2 microSi/hour with the "low 37 MBq (1 mCi) 99mTc-sestamibi dose", and less than 1.0 microSi/hour for the other operating-room personnel. Focused low dose radioguided parathyroidectomy is a safe and effective means to localize parathyroid adenomas in patients affected by solitary PA thus reducing by 20 fold the radiation exposure dose to the patients and operating room personnel. PMID:16978398

  8. Does the Clearance of Inhaled (99m)Tc-Sestamibi Correlate with Multidrug Resistance Protein 1 Expression in the Human Lung?

    PubMed

    Mohan, Hosahalli K; Routledge, Thomas; Cane, Paul; Livieratos, Lefteris; Ballinger, James R; Peters, Adrien M

    2016-09-01

    Purpose To examine the relation between the lung elimination rate of inhaled technetium 99m ((99m)Tc)-sestamibi and immunohistochemical expression of bronchopulmonary multidrug resistance protein 1 (MRP1) and permeability glycoprotein (P-gp) and assess the repeatability of the inhaled (99m)Tc-sestamibi clearance technique. Materials and Methods (99m)Tc-sestamibi is a known substrate for P-gp and MRP1, which are established cellular drug efflux transporters. The elimination rate of (99m)Tc-sestamibi from the lungs after inhalation as an aerosol has been hypothesized to be regulated by expression of these transporters. Institutional ethics committee approval was received for this prospective study. Written informed consent was obtained from all participants. The clearance of inhaled (99m)Tc-sestamibi from the lungs of 13 patients due to undergo surgery for primary lung cancer (five of 13) or spontaneous pneumothorax (eight of 13) was estimated after dynamic imaging of the lungs during a period of 40 minutes. The time taken to clear 50% of inhaled sestamibi (T1/2) was compared with a semiquantitative immunohistochemical assessment (grade 0-3) of MRP1 and P-gp expression in the lung by using parametric and nonparametric tests. The study was repeated in five participants to assess the repeatability of the technique by using a Bland Altman analysis method. Results MRP1 expression was seen in 12 of 13 patients, while P-gp expression was seen in only two. The mean (99m)Tc-sestamibi elimination rate was faster in patients (n = 6) with low levels of MRP1 expression (grade 0-1) and mean T1/2 of 105 minutes ± 20 (standard deviation), compared with those with higher levels of MRP1 expression (grade 2-3, n = 7) and mean T1/2 of 149 minutes ± 28 (P = .008). Bland-Altman analysis revealed excellent agreement between test and retest values. Conclusion Inhaled (99m)Tc-sestamibi clearance study is a repeatable technique demonstrating significant correlation with MRP1 expression in

  9. A geometric method of measuring the left ventricular ejection fraction on gated Tc-99m sestamibi myocardial imaging.

    PubMed

    Miron, S D; Finkelhor, R; Penuel, J H; Bahler, R; Bellon, E M

    1996-06-01

    Geometric measurements of the left ventricular diameters as used in biplane angiocardiography and echocardiography were applied to gated SPECT Tc-99m sestamibi myocardial scintigrams in order to calculate the left ventricular ejection fraction. These measurements take no longer than 5 minutes and require no additional computer software. In a review of 79 examinations, the left ventricular ejection fraction calculated using these measurements correlated well with the echocardiographically estimated ejection fraction (r = 0.78, P < 0.0001). The technique is highly reproducible with an intraobserver correlation of r = 0.94 and interobserver correlation of r = 0.93. PMID:8744176

  10. Pituitary Prolactinoma Imaged by 99mTc-Sestamibi SPECT/CT in a Multiple Endocrine Neoplasia Type 1 Patient.

    PubMed

    Pan, Yu; Lv, Jing; Guo, Rui; Pan, Mengyi; Zhang, Yifan

    2016-06-01

    A 35-year-old woman who had undergone bilateral inferior parathyroidectomy for primary hyperparathyroidism was referred to our hospital to evaluate the cause of irregular menses, galactorrhea, and paroxysmal headache. Multiple endocrine neoplasia type 1 was then suspected for the high levels of plasma prolactin, parathyroid hormone, serum calcium, insulin, and related symptoms. A Tc-sestamibi SPECT/CT acquired to evaluate parathyroid glands unexpectedly revealed an increased accumulation in the pituitary gland, which was further confirmed by enhanced magnetic resonance imaging as a pituitary microadenoma. Bromocriptine treatment gradually reduced the prolactin level. PMID:26828146

  11. Biodistribution of TC-99m sestamibi in rats utilizing whole-body autoradiography

    SciTech Connect

    Combs, M.J.; Croft, B.Y.; Arora, J.

    1994-05-01

    Current biodistribution models for Tc-99m sestamibi (MIBI) rely on gross imaging methods via Anger camera or at best, excision of animal tissue and counting tissue samples. These methods do not allow for detection of intra-organ inhomogeneities and small accumulations of activity are often treated as nonspecific background. The goal of this work was to examine the biodistribution of MIBI using whole-body autoradiography to obtain very detailed activity distribution information. Four anesthetized albino rats (300 g {plus_minus}10 g ) were injected into a dorsal metatarsal vein with an average of 333 MBq MIBI. One rat each was sacrificed at 5, 20, 60 and 180 minutes post-injection. Animals were embedded, frozen and slices (50-100 {mu}m thick) were obtained using a PMV-2250 macro-cryo-microtome and autoradiographs were made of slices. Cardiac uptake remained consistently high at all time points. All muscular areas exhibited uptake, including the diaphragm and GI tract wells. Significant MIBI uptake was observed in many different glands, including the submaxillary, suprarenal, thymus, lacrimal, harderian and thyroid. Pancreatic uptake was observed at each time. MIBI cleared from the liver and spleen quickly, with significant activity in the bowel at 5 minutes. High small bowel content activity was observed at all time points. The contents of the distal stomach and colon accumulated activity in all but the 5 minute studies. Clearance from the kidneys occurred between 1 and 3 hours, although kidney activity remained similar to the heart at 3 hours. Bladder activity was observed as early as 20 minutes, with the highest at the 3 hour time point. Very slight testicular uptake was observed in the epidydmis and wall of the scrotal sac. Although these autoradiographs confirm existing kinetics, they provide a unique, high-resolution record of previously unknown MIBI deposition areas such as the pancreas and GI tract lining.

  12. Tc-99m sestamibi uptake in small cell lung cancer: A predictor of response to chemotherapy

    SciTech Connect

    Bom, H.S.; Kim, Y.C.; Song, H.C.

    1996-05-01

    Patients(pts) with small cell lung cancer(SCLC) often fail to respond to chemotherapy due to multi-drug resistance(MDR). Tc-99m sestamibi (MIBI) was reported to be a suitable transport substrate of P-glycoprotein, a cytoplasmic membrane protein encoded by the MDR gene. The purpose of this study was to evaluate whether or not the degree of MIBI uptake in SCLC or its retention on delayed imaging correlated with response to chemotherapy. 19 pts (M:F=13:6, mean age 60.2 {plus_minus} 10.9) with biopsy-proven SCLC had MIBI SPECT 3 to 7 days before starting chemotherapy. Imaging was acquired 1 and 4 hours after injection of 740MBq MIBI using single head rotating gamma camera. Tumor-to-normal lung uptake ratio(T/NL) was measured. Per cent retention(%R) was measured as: %R = (T/NL at 4 hour {divided_by} T/NL at 1 hour) X 100. All patients received VAP chemotherapy (VP-16 100mg/m{sup 2}, adriamycin 40mg/m{sup 2}, cisplatin 25mg/m{sup 2}) every 4 weeks for at least 3 times. Response to chemotherapy was grouped as complete remission(CR), partial remission (PR), and no remission(NR) according to the change of tumor size on chest X-ray and computed tomographic images. Differences in T/NL and %R among the 3 groups were analyzed using ANOVA. These preliminary data indicate that SCLC with a higher MIBI uptake is more likely to respond to chemotherapy than that with a lower uptake. However, there was no significant correlation between the MIBI retention and the response to chemotherapy.

  13. WBC scan

    MedlinePlus

    ... in the body. It is a type of nuclear scan . How the Test is Performed Blood will ... radiation. Due to the slight radiation exposure, most nuclear scans (including WBC scan) are not recommended for ...

  14. CT scan

    MedlinePlus

    CAT scan; Computed axial tomography scan; Computed tomography scan ... Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, et al. eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging . 6th ...

  15. Nuclear Scans

    MedlinePlus

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  16. Quantitative assessment of myocardial 99mTc-sestamibi uptake during exercise: usefulness of response rate for assessing severity of coronary artery disease.

    PubMed

    Fujiwara, S; Takeishi, Y; Atsumi, H; Chiba, J; Takahashi, K; Tomoike, H

    1998-08-01

    An increase of 99mTc-sestamibi uptake in the myocardium during exercise was defined as a response rate, and the feasibility of a response rate for detecting coronary artery disease (CAD) was tested. Eighty-seven patients with suspected CAD had myocardial perfusion imaging with 99mTc-sestamibi during exercise and at rest. A dose of 370 MBq of 99mTc-sestamibi was injected at the maximal level of exercise, and a myocardial image was obtained 90 min later (exercise image). Then, 740 MBq of 99mTc-sestamibi was administered at rest, and myocardial imaging was repeated (rest image). The exercise and rest images were corrected for physical decay and injected doses, and the exercise image was subtracted from the rest image to obtain the corrected rest image. A response rate was calculated as follows: (exercise image-corrected rest image)x100/corrected rest image (%). The global response rates of 20 patients without significant coronary stenosis (< or =50%) were higher than those of 67 patients with significant coronary stenosis (81+/-33% and 50+/-28%, p<0.01). Global response rates were correlated with the maximal rate pressure products during exercise (r=0.56, p<0.01) and delta rate pressure products (r=0.53, p<0.01). Regional response rates in myocardial areas perfused by stenotic coronary arteries of < or =50%, 75%, 90% and 99-100% were 60+/-24%,* 56+/-33%,* 40+/-23%* and 30+/-23%,* respectively, (*p<0.01 vs without significant coronary stenosis). The response rates decreased as the severity of coronary artery stenosis advanced, and distinguished between coronary stenoses of graded severity. Accordingly, the response rate from myocardial perfusion imaging with 99mTc-sestamibi may provide complementary information to the conventional inspection with myocardial tomography regarding the severity of CAD. PMID:9741737

  17. PET scan

    MedlinePlus

    You may feel a sharp sting when the needle with the tracer is placed into your vein. A PET scan causes no pain. The table may be ... The amount of radiation used in a PET scan is about the same amount as used in most CT scans. These scans use ...

  18. Immobilization of 99-Technetium (VII) by Fe(II)-Goethite and Limited Reoxidation

    SciTech Connect

    W Um; H Chang; J Icenhower; W Lukens; R Serne; N Qafoku; J Westsik Jr.; E Buck; S Smith

    2011-12-31

    During the nuclear waste vitrification process volatilized {sup 99}Tc will be trapped by melter off-gas scrubbers and then washed out into caustic solutions, and plans are currently being contemplated for the disposal of such secondary waste. Solutions containing pertechnetate [{sup 99}Tc(VII)O{sub 4}{sup -}] were mixed with precipitating goethite and dissolved Fe(II) to determine if an iron (oxy)hydroxide-based waste form can reduce Tc(VII) and isolate Tc(IV) from oxygen. The results of these experiments demonstrate that Fe(II) with goethite efficiently catalyzes the reduction of technetium in deionized water and complex solutions that mimic the chemical composition of caustic waste scrubber media. Identification of the phases, goethite + magnetite, was performed using XRD, SEM and TEM methods. Analyses of the Tc-bearing solid products by XAFS indicate that all of the Tc(VII) was reduced to Tc(IV) and that the latter is incorporated into goethite or magnetite as octahedral Tc(IV). Batch dissolution experiments, conducted under ambient oxidizing conditions for more than 180 days, demonstrated a very limited release of Tc to solution (2-7 {micro}g Tc/g solid). Incorporation of Tc(IV) into the goethite lattice thus provides significant advantages for limiting reoxidation and curtailing release of Tc disposed in nuclear waste repositories.

  19. Feasibility study of accelerator based production of molybdenum-99/technetium-99m

    NASA Astrophysics Data System (ADS)

    Tchelidze, Lali

    Stability of supply in the medical radioisotope market is now of overriding importance. One of the most commonly used radioisotopes is 99mTc, which is produced from 99Mo decay. 99Mo has been produced in nuclear reactors before, however these reactors are aging and have been not reliable lately and there is a great need to find an alternative for the production. In the current project, photo-neutron production of 99Mo/ 99mTc was investigated. An electron linear accelerator at the Idaho Accelerator Center was used to study the feasibility of 99mTc production using bremsstrahlung photon beams from the accelerator. The kinematic recoil process that occurs with every photo nuclear reaction was exploited. With the emission of a neutron in a photo nuclear reaction, the parent nucleus recoils in order to conserve momentum. This recoil can be used to separate 99Mo from 100Mo, at which point one has a very pure and very high specific activity source of 99Mo. We verified the photo-neutron production rates for 99Mo. Also, the kinematic recoil process was modeled and separation efficiencies were measured experimentally. We concluded that it is feasible to produce high 99Mo activities, however nano-particles of molybdenum have to be used and a clean nano-particle separation method has to be achieved.

  20. Future of low specific activity molybdenum-99/technetium-99m generator.

    PubMed

    Mushtaq, A

    2012-10-01

    In last few years, the shortage of molybdenum-99 (99Mo) was felt in the developed and developing countries hospitals, where diagnostic nuclear medicine is practiced. To overcome the shortage of 99Mo various routes of its production by accelerators and reactors generating low and high specific activity products have been planned. High specific activity 99Mo obtained by fission of uranium-235 (235U) has completely dominated in the manufacturing of technetium-99m (99mTc) generators in last 3-4 decades, but due to proliferation and dirty bomb, issues non fission routes of 99Mo production are emphasized. Future of low specific activity 99Mo is discussed. PMID:22642420

  1. Half-time Tc-99m sestamibi imaging with a direct conversion molecular breast imaging system

    PubMed Central

    2014-01-01

    Background In an effort to reduce necessary acquisition time to perform molecular breast imaging (MBI), we compared diagnostic performance of MBI performed with standard 10-min-per-view acquisitions and half-time 5-min-per-view acquisitions, with and without wide beam reconstruction (WBR) processing. Methods Eighty-two bilateral, two-view MBI studies were reviewed. Studies were performed with 300 MBq Tc-99 m sestamibi and a direct conversion molecular breast imaging (DC-MBI) system. Acquisitions were 10 min-per-view; the first half of each was extracted to create 5-min-per-view datasets, and WBR processing was applied. The 10-min-, 5-min-, and 5-min-per-view WBR studies were independently interpreted in a randomized, blinded fashion by two radiologists. Assessments of 1 to 5 were assigned; 4 and 5 were considered test positive. Background parenchymal uptake, lesion type, distribution of non-mass lesions, lesion intensity, and image quality were described. Results Considering detection of all malignant and benign lesions, 5 min-per-view MBI had lower sensitivity (mean of 70% vs. 85% (p ≤ 0.04) for two readers) and lower area under curve (AUC) (mean of 92.7 vs. 99.6, p ≤ 0.01) but had similar specificity (p = 1.0). WBR processing did not alter sensitivity, specificity, or AUC obtained at 5 min-per-view. Overall agreement in final assessment between 5-min-per-view and 10-min-per-view acquisition types was near perfect (κ = 0.82 to 0.89); however, fair to moderate agreement was observed for assessment category 3 (probably benign) (κ = 0.24 to 0.48). Of 33 malignant lesions, 6 (18%) were changed from assessment of 4 or 5 with 10-min-per-view MBI to assessment of 3 with 5-min-per-view MBI. Image quality of 5-min-per-view studies was reduced compared to 10-min-per-view studies for both readers (3.24 vs. 3.98, p < 0.0001 and 3.60 vs. 3.91, p < 0.0001). WBR processing improved image quality for one reader (3.85 vs. 3.24, p < 0

  2. CT Scans

    MedlinePlus

    ... cross-sectional pictures of your body. Doctors use CT scans to look for Broken bones Cancers Blood clots Signs of heart disease Internal bleeding During a CT scan, you lie still on a table. The table ...

  3. Gallium scan

    MedlinePlus

    Liver gallium scan; Bony gallium scan ... You will get a radioactive material called gallium injected into your vein. The gallium travels through the bloodstream and collects in the bones and certain organs. Your health care provider will ...

  4. Bone scan

    MedlinePlus

    ... scan is an imaging test used to diagnose bone diseases and find out how severe they are. How ... a 3-phase bone scan. To evaluate metastatic bone disease, images are taken only after the 3- to ...

  5. Thyroid scan

    MedlinePlus

    ... Read More Anaplastic thyroid cancer Cancer Goiter - simple Hyperthyroidism Multiple endocrine neoplasia (MEN) II PET scan Skin ... A.M. Editorial team. Related MedlinePlus Health Topics Hyperthyroidism Hypothyroidism Nuclear Scans Thyroid Cancer Thyroid Diseases Thyroid ...

  6. Bone scan

    MedlinePlus

    A bone scan is an imaging test used to diagnose bone diseases and find out how severe they are. ... A bone scan involves injecting a very small amount of radioactive material (radiotracer) into a vein. The substance travels through ...

  7. Bone scanning.

    PubMed

    Greenfield, L D; Bennett, L R

    1975-03-01

    Scanning is based on the uptake of a nuclide by the crystal lattice of bone and is related to bone blood flow. Cancer cells do not take up the tracer. Normally, the scan visualizes the highly vascular bones. Scans are useful and are indicated in metastatic bone disease, primary bone tumors, hematologic malignancies and some non-neoplastic diseases. The scan is more sensitive than x-ray in the detection of malignant diseases of the skeleton. PMID:1054210

  8. Use of the cavity-to-myocardial count ratio with Tc-99m sestamibi myocardial perfusion SPECT to predict reduced left ventricular function

    SciTech Connect

    Heerden, B.B. van; Heerden, P.D.R. van; Wasserman, H.J.

    1994-05-01

    In patients with left ventricular dysfunction, the left ventricular cavity appears abnormally photopenic on SPECT images, both with T1-201 and Tc-99m sestamibi showed a linear correlation between the cavity-to-myocardial count ratio (C/M ratio) and left ventricular ejection fraction (LVEF) with T1-201 SPECT. Using an exercise ratio of 0.4 as the lower limit of normal, they could predict a reduced LVEF with a sensitivity of 83% and specificity of 78%. The purpose of our study was to ascertain whether the C/M ratio could also be used as an indicator of LVEF when using Tc-99m sestamibi as imaging agent.

  9. Initial In Vivo Quantification of Tc-99m Sestamibi Uptake as a Function of Tissue Type in Healthy Breasts Using Dedicated Breast SPECT-CT

    PubMed Central

    Mann, Steve D.; Perez, Kristy L.; McCracken, Emily K. E.; Shah, Jainil P.; Wong, Terence Z.; Tornai, Martin P.

    2012-01-01

    A pilot study is underway to quantify in vivo the uptake and distribution of Tc-99m Sestamibi in subjects without previous history of breast cancer using a dedicated SPECT-CT breast imaging system. Subjects undergoing diagnostic parathyroid imaging studies were consented and imaged as part of this IRB-approved breast imaging study. For each of the seven subjects, one randomly selected breast was imaged prone-pendant using the dedicated, compact breast SPECT-CT system underneath the shielded patient support. Iteratively reconstructed and attenuation and/or scatter corrected images were coregistered; CT images were segmented into glandular and fatty tissue by three different methods; the average concentration of Sestamibi was determined from the SPECT data using the CT-based segmentation and previously established quantification techniques. Very minor differences between the segmentation methods were observed, and the results indicate an average image-based in vivo Sestamibi concentration of 0.10 ± 0.16 μCi/mL with no preferential uptake by glandular or fatty tissues. PMID:22956950

  10. A review of the cost-effectiveness of Tc-99m sestamibi scintimammography in diagnosis of breast cancer in Taiwanese women with indeterminate mammographically dense breast.

    PubMed

    Chen, Yi-Shan; Wang, Wei-Hua; Chan, Tam; Sun, Shung-Shung; Kao, Albert

    2002-11-01

    In general, biopsy is the preferred management method for women with indeterminate mammographically dense breasts. In this review, we describe a decision analysis model comparing technetium-99m methoxyisobutylisonitrile (Tc-99m sestamibi) scintimammography and excisional biopsy as breast cancer evaluation strategies for hypothetical cohorts of estimated 16,000-40,000 women with indeterminate mammographic probability of malignancy because of mammographically dense breasts. In cost-effectiveness analysis, quantitative decision tree sensitivity analysis was used to compare the conventional excision biopsy alone strategy (strategy A) with decision strategy for screening with Tc-99m sestamibi scintimammography before excision biopsy (strategy B) after an indeterminate mammogram. Strategy B showed a cost saving of US dollars 649,600-1,624,000 in reducing the cost of unnecessary biopsies. The total cost of strategy B showed a cost saving of US dollars 123,075-307,776 compared to strategy A. The analysis data indicate that Tc-99m sestamibi scintimammography can save the cost of unnecessary biopsies in Taiwanese women with non-diagnostic mammogram because of mammographically dense breasts. PMID:12356511

  11. Tree Scanning

    PubMed Central

    Templeton, Alan R.; Maxwell, Taylor; Posada, David; Stengård, Jari H.; Boerwinkle, Eric; Sing, Charles F.

    2005-01-01

    We use evolutionary trees of haplotypes to study phenotypic associations by exhaustively examining all possible biallelic partitions of the tree, a technique we call tree scanning. If the first scan detects significant associations, additional rounds of tree scanning are used to partition the tree into three or more allelic classes. Two worked examples are presented. The first is a reanalysis of associations between haplotypes at the Alcohol Dehydrogenase locus in Drosophila melanogaster that was previously analyzed using a nested clade analysis, a more complicated technique for using haplotype trees to detect phenotypic associations. Tree scanning and the nested clade analysis yield the same inferences when permutation testing is used with both approaches. The second example is an analysis of associations between variation in various lipid traits and genetic variation at the Apolipoprotein E (APOE) gene in three human populations. Tree scanning successfully identified phenotypic associations expected from previous analyses. Tree scanning for the most part detected more associations and provided a better biological interpretative framework than single SNP analyses. We also show how prior information can be incorporated into the tree scan by starting with the traditional three electrophoretic alleles at APOE. Tree scanning detected genetically determined phenotypic heterogeneity within all three electrophoretic allelic classes. Overall, tree scanning is a simple, powerful, and flexible method for using haplotype trees to detect phenotype/genotype associations at candidate loci. PMID:15371364

  12. Nuclear Scans

    MedlinePlus

    ... functions inside your body. They use a special camera that detects radioactivity. Before the test, you receive ... you lie still on a table while the camera makes images. Most scans take 20 to 45 ...

  13. MRI Scans

    MedlinePlus

    Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans to diagnose a variety of conditions, from torn ...

  14. Parathyroid scintigraphy in patients with primary hyperparathyroidism: 99mTc sestamibi SPECT and SPECT/CT.

    PubMed

    Eslamy, Hedieh K; Ziessman, Harvey A

    2008-01-01

    The clinical diagnosis of primary hyperparathyroidism is based largely on serum laboratory test results, as patients often are asymptomatic. Surgery, often with bilateral exploration of the neck, has been considered the definitive treatment for symptomatic disease. However, given that approximately 90% of cases are due to a single parathyroid adenoma, a better treatment may be the selective surgical excision of the hyperfunctioning parathyroid gland after its preoperative identification and localization at radiologic imaging. Scintigraphy and ultrasonography are the imaging modalities most often used for preoperative localization. Various scintigraphic protocols may be used in the clinical setting: Single-phase dual-isotope subtraction imaging, dual-phase single-isotope imaging, or a combination of the two may be used to obtain planar or tomographic views. Single photon emission computed tomography (SPECT) with the use of technetium-99m ((99m)Tc) sestamibi as the radiotracer, especially when combined with x-ray-based computed tomography (CT), is particularly helpful for preoperative localization: The three-dimensional functional information from SPECT is fused with the anatomic information obtained from CT. In addition, knowledge of the anatomy and embryologic development of the parathyroid glands and the pathophysiology of primary hyperparathyroidism aid in the identification and localization of hyperfunctioning glands. PMID:18794320

  15. Tl-201 and Tc-99m-Sestamibi SPECT for brain tumor detection: Comparison using MRI coregistration

    SciTech Connect

    Darcourt, J.; Itti, L.; Chang, L.

    1994-05-01

    Tl-201 (Tl) brain SPECT has been validated for the differential diagnosis of high versus low grade gliomas and recurrence versus radiation necrosis. We compared this technique to Tc-99m-Sestamibi (MIBI) SPECT in 9 patients (pts) with brain tumors using MRI coregistration. Pts were injected with 4 mCi of Tl and brain SPECT was performed using a dedicated brain system. This was immediately following by an injection of 20 mCi of MIBI and a brain SPECT using the same camera and with the pt in the same position. Four pts were studied for the diagnosis of radiation necrosis vs. tumor recurrence (2 had biopsy proven recurrence); 5 pts were studied for primary tumor evaluation: 2 meningiomas, 1 oligodendroglioma, 1 low-grade astrocytoma, 1 cysticercosis. Coregistration was performed for every pt by 3D surface fitting of the inner skull MIBI contour to the MRI brain surface extracted automatically. ROIs were drawn on the MRI and applied to the coregistered MIBI and Tl images for tumor to non-tumor ratios T/NT calculations. There was a tight correlation between MIBI and Tl T/NT (r-0.96) and a 1.5 threshold separated radiation necrosis from recurrence and low from high grade primary tumors. Therefore, the data already available on Tl brain tumor imaging can be used with MIBI SPECT with the advantage of a better image quality (2.5 to 4 times more counts).

  16. Assessment of cardiac function using myocardial perfusion imaging technique on SPECT with 99mTc sestamibi

    NASA Astrophysics Data System (ADS)

    Gani, M. R. A.; Nazir, F.; Pawiro, S. A.; Soejoko, D. S.

    2016-03-01

    Suspicion on coronary heart disease can be confirmed by observing the function of left ventricle cardiac muscle with Myocardial Perfusion Imaging techniques. The function perfusion itself is indicated by the uptake of radiopharmaceutical tracer. The 31 patients were studied undergoing the MPI examination on Gatot Soebroto Hospital using 99mTc-sestamibi radiopharmaceutical with stress and rest conditions. Stress was stimulated by physical exercise or pharmacological agent. After two hours, the patient did rest condition on the same day. The difference of uptake percentage between stress and rest conditions will be used to determine the malfunction of perfusion due to ischemic or infarct. Degradation of cardiac function was determined based on the image-based assessment of five segments of left ventricle cardiac. As a result, 8 (25.8%) patients had normal myocardial perfusion and 11 (35.5%) patients suspected for having partial ischemia. Total ischemia occurred to 8 (25.8%) patients with reversible and irreversible ischemia and the remaining 4 (12.9%) patients for partial infarct with characteristic the percentage of perfusion ≤50%. It is concluded that MPI technique of image-based assessment on uptake percentage difference between stress and rest conditions can be employed to predict abnormal perfusion as complementary information to diagnose the cardiac function.

  17. Assessment of Myocardial Scar; Comparison Between 18F-FDG PET, CMR and 99Tc-Sestamibi

    PubMed Central

    Crean, Andrew; Khan, Sadia N.; Davies, L. Ceri; Coulden, Richard; Dutka, David P.

    2009-01-01

    Objective: Patients with heart failure and ischaemic heart disease may obtain benefit from revascularisation if viable dysfunctional myocardium is present. Such patients have an increased operative risk, so it is important to ensure that viability is correctly identified. In this study, we have compared the utility of 3 imaging modalities to detect myocardial scar. Design: Prospective, descriptive study. Setting: Tertiary cardiac centre. Patients: 35 patients (29 male, average age 70 years) with coronary artery disease and symptoms of heart failure (>NYHA class II). Intervention: Assessment of myocardial scar by 99Tc-Sestamibi (MIBI), 18F-flurodeoxyglucose (FDG) and cardiac magnetic resonance (CMR). Outcome Measure: The presence or absence of scar using a 20-segment model. Results: More segments were identified as nonviable scar using MIBI than with FDG or CMR. FDG identified the least number of scar segments per patient (7.4 +/− 4.8 with MIBI vs. 4.9 +/− 4.2 with FDG vs. 5.8 +/− 5.0 with CMR, p = 0.0001 by ANOVA). The strongest agreement between modalities was in the anterior wall with the weakest agreement in the inferior wall. Overall, the agreement between modalities was moderate to good. Conclusion: There is considerable variation amongst these 3 techniques in identifying scarred myocardium in patients with coronary disease and heart failure. MIBI and CMR identify more scar than FDG. We recommend that MIBI is not used as the sole imaging modality in patients undergoing assessment of myocardial viability. PMID:20508767

  18. Determination of correlated uncertainties of sestamibi- 99mTc marking

    NASA Astrophysics Data System (ADS)

    Sousa, C. H. S.; Gama, A.; Camilo, T. G. N.; Mesquita, C. T.; Peixoto, J. G. P.

    2016-07-01

    The input quantities determination involved in radiopharmaceutical marking used in heart scans allowed to estimate the combined and associated standard uncertainty with the process. The U value demonstrated that any parameter of the quality control process can be compared and correlated to obtain a real value and validation method, indicating or not, the adequacy of institutional practices and reinforcing the importance of the uncertainties associated to the results in medicine.

  19. Infrared Scanning

    NASA Technical Reports Server (NTRS)

    1987-01-01

    United Scanning Technologies, Inc.'s Infrared thermography is a relatively new noncontact, nondestructive inspection and testing tool which makes temperatures visible to the human eye. Infrared scanning devices produce images that show, by color or black and white shading differences, heat losses through damaged or inadequately insulated walls or roofs. The MISS Aeroscan services are designed to take the guesswork out of industrial roof maintenance and provide companies big savings by identifying the location of moisture damage from roof leaks, effectively targeting maintenance attention.

  20. Heart CT scan

    MedlinePlus

    CAT scan - heart; Computed axial tomography scan - heart; Computed tomography scan - heart; Calcium scoring; Multi-detector CT scan - heart; Electron beam computed tomography - heart; Agaston score; Coronary calcium scan

  1. Thallium-pertechnetate subtraction scanning in the preoperative localization of an ectopic undescended parathyroid gland.

    PubMed

    Frydman, James; Bianco, Jesus; Drezner, Marc; Chen, Herbert

    2004-09-01

    Although bilateral exploration is highly effective in the treatment of primary hyperparathyroidism, minimally invasive parathyroidectomy has evolved into the procedure of choice when a single parathyroid lesion can be localized preoperatively. In this article, we discuss the utilization of thallium-pertechnetate subtraction scanning (TPSS) after technetium Tc-99m sestamibi scintigraphy failed to localize an ectopic parathyroid adenoma. Subsequently, radioguided resection of an undescended parathyroid adenoma inferior to the left submandibular gland was performed with surgical cure after a single procedure. This case report illustrates the importance of TPSS as a second-line modality in preoperative adenoma localization, thereby using minimally invasive techniques to successfully treat this patient's primary hyperparathyroidism. PMID:15311119

  2. Gallbladder radionuclide scan

    MedlinePlus

    ... Gallbladder scan; Biliary scan; Cholescintigraphy: HIDA; Hepatobiliary nuclear imaging scan ... test results. This test is combined with other imaging (such as CT or ultrasound). After the gallbladder ...

  3. The association of increased stomach wall radiotracer uptake with prolonged use of omeprazole capsules on myocardial perfusion imaging (MPI) using 99mTc-sestamibi SPECT.

    PubMed

    Javadi, Hamid; Jallalat, Sara; Semnani, Shahriar; Mogharrabi, Mehdi; Nabipour, Iraj; Tabib, Seyed Masoud; Abbaszadeh, Moloud; Assadi, Majid

    2013-01-01

    Myocardial perfusion imaging (MPI) is widely used in routine practice for diagnosis and risk stratification of coronary artery disease (CAD). Intense curvilinear activity in the stomach wall of a patient was seen on MPI raw data. This phenomenon was completely dissimilar to the familiar intraluminal gastric reflux of sestamibi. This observed activity could have resulted in false-positive or false-negative artifacts - and inaccurate diagnosis - of the inferior wall of the left ventricle after MPI processing. On further exploration, the current researchers found that the patient had a history of 10-year Omeprazole capsule consumption. The authors present this infrequent case of intense stomach uptake to stress the related clinical and diagnostic implications with the aim to stimulate acute awareness of possible, unexpected infringements on image quality that could potentially interfere with accurate interpretation of the data. PMID:24068640

  4. Comparison of myocardial contrast echocardiography with NC100100 and 99mTc sestamibi SPECT for detection of resting myocardial perfusion abnormalities in patients with previous myocardial infarction

    PubMed Central

    Jucquois, I; Nihoyannopoulos, P; D'Hondt, A; Roelants, V; Robert, A; Melin, J; Glass, D; Vanoverschelde, J

    2000-01-01

    OBJECTIVE—To determine whether myocardial contrast echocardiography (MCE) following intravenous injection of perfluorocarbon microbubbles permits identification of resting myocardial perfusion abnormalities in patients who have had a previous myocardial infarction.
PATIENTS AND INTERVENTIONS—22 patients (mean (SD) age 66 (11) years) underwent MCE after intravenous injection of NC100100, a novel perfluorocarbon containing contrast agent, and resting 99mTc sestamibi single photon emission computed tomography (SPECT). With both methods, myocardial perfusion was graded semiquantitatively as 1 = normal, 0.5 = mild defect, and 0 = severe defect.
RESULTS—Among the 203 normally contracting segments, 151 (74%) were normally perfused by SPECT and 145 (71%) by MCE. With SPECT, abnormal tracer uptake was mainly found among normally contracting segments from the inferior wall. By contrast, with MCE poor myocardial opacification was noted essentially among the normally contracting segments from the anterior and lateral walls. Of the 142 dysfunctional segments, 87 (61%) showed perfusion defects by SPECT, and 94 (66%) by MCE. With both methods, perfusion abnormalities were seen more frequently among akinetic than hypokinetic segments. MCE correctly identified 81/139 segments that exhibited a perfusion defect by SPECT (58%), and 135/206 segments that were normally perfused by SPECT (66%). Exclusion of segments with attenuation artefacts (defined as abnormal myocardial opacification or sestamibi uptake but normal contraction) by either MCE or SPECT improved both the sensitivity (76%) and the specificity (83%) of the detection of SPECT perfusion defects by MCE.
CONCLUSIONS—The data suggest that MCE allows identification of myocardial perfusion abnormalities in patients who have had a previous myocardial infarction, provided that regional wall motion is simultaneously taken into account.


Keywords: myocardial contrast echocardiography; NC100100

  5. Head CT scan

    MedlinePlus

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial ... or other growth (mass) Cerebral atrophy (loss of brain tissue) ... with the hearing nerve Stroke or transient ischemic attack (TIA)

  6. Abscess scan - radioactive

    MedlinePlus

    Radioactive abscess scan; Abscess scan; Indium Scan; Indium-labelled white blood cell scan ... the white blood cells are tagged with a radioactive substance called indium. The cells are then injected ...

  7. Arm CT scan

    MedlinePlus

    CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... Mosby; 2013:chap 57. Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, Schaefer- ...

  8. Sinus CT scan

    MedlinePlus

    CAT scan - sinus; Computed axial tomography scan - sinus; Computed tomography scan - sinus; CT scan - sinus ... 2014:chap 67. Shaw AS, Dixon AK. Multidetector computed tomography. In: Adam A, Dixon AK, eds. Grainger & Allison's ...

  9. Leg CT scan

    MedlinePlus

    CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... Saunders; 2012:chap 11. Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, Schaefer- ...

  10. Pelvic CT scan

    MedlinePlus

    CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... gov/pubmed/18381118 . Shaw AS, Dixon AK. Multidetector computed tomography. In: Grainger RC, Allison D, Adam, Dixon AK, ...

  11. Shoulder CT scan

    MedlinePlus

    CAT scan - shoulder; Computed axial tomography scan - shoulder; Computed tomography scan - shoulder; CT scan - shoulder ... Mosby; 2012:chap 57. Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, Schaefer- ...

  12. Evaluation of 99mTcN-MPO as a New Myocardial Perfusion Imaging Agent in Normal Dogs and in an Acute Myocardial Infarction Canine Model: Comparison with 99mTc-Sestamibi

    PubMed Central

    Bu, Lihong; Li, Renfei; Jin, Zhongnan; Wen, Xiaofei; Liu, Shuang; Yang, Baofeng; Shen, Baozhong; Chen, Xiaoyuan

    2010-01-01

    Purpose 99mTcN-MPO ([99mTcN(mpo)(PNP5)]+: mpo=2-mercaptopyridine oxide and PNP5=N-ethoxyethyl-N,N-bis[2-(bis(3-methoxypropyl)phosphino)ethyl]amine) is a cationic 99mTc-nitrido complex, which has favorable biodistribution and myocardial uptake with rapid liver clearance in Sprague Dawley rats. The objective of this study was to compare the biodistribution and pharmacokinetics of 99mTcN-MPO and 99mTc-Sestamibi in normal dogs, and to evaluate the potential of 99mTcN-MPO as a myocardial perfusion agent in canines with acute myocardial infarction. Methods Five normal mongrel dogs were injected intravenously with 99mTcN-MPO. Venous blood samples were collected via a femoral vein catheter at 0.5, 1, 2, 3, 4, 5, 10, 20, 30, 40, 60, and 90 min post-injection (p.i.). Anterior-posterior planar images were acquired by γ-camera at 10, 20, 30, 60, 90, and 120 min p.i. Regions of interest (ROIs) were drawn around the heart, liver, and lungs. The heart/liver and heart/lung ratios were calculated by dividing the mean counts in heart ROI by the mean counts in the liver and lung ROI, respectively. For comparison, 99mTc-sestamibi was also evaluated in the same five dogs. The interval period between the two examinations was 1 week to eliminate possible interference between these two radiotracers. In addition, single positron emission computed tomography (SPECT) images in the canine infarct model were collected 24 h after myocardial infarction at 30 and 60 min after the administration of 99mTcN-MPO (n=4) or 99mTc-Sestamibi (n=4). Results It was found that 99mTcN-MPO and 99mTc-Sestamibi displayed very similar blood clearance characteristics during the first 90 min p.i. Both 99mTcN-MPO and 99mTc-Sestamibi had a rapid blood clearance with less than 50% of initial radioactivity remaining at 1 min and less than 5% at 30 min p.i. 99mTcN-MPO and 99mTc-Sestamibi both showed good heart/lung contrast. The heart/liver ratio of 99mTcN-MPO increased with time (0.53±0.06 at 10 min, 0.90±0.062 at

  13. Coronary Calcium Scan

    MedlinePlus

    ... the NHLBI on Twitter. What Is a Coronary Calcium Scan? A coronary calcium scan is a test ... you have calcifications in your coronary arteries. Coronary Calcium Scan Figure A shows the position of the ...

  14. Heart PET scan

    MedlinePlus

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  15. Knee CT scan

    MedlinePlus

    CAT scan - knee; Computed axial tomography scan - knee; Computed tomography scan - knee ... Saunders; 2015:chap 93. Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, Schaefer- ...

  16. Lumbar spine CT scan

    MedlinePlus

    CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... stopping.) A computer creates separate images of the spine area, called slices. These images can be stored, ...

  17. Systematic evaluation of 99mTc-tetrofosmin versus 99mTc-sestamibi to study murine myocardial perfusion in small animal SPECT/CT

    PubMed Central

    2012-01-01

    Background The “back-translation” of clinically available protocols to measure myocardial perfusion to preclinical imaging in mouse models of human disease is attractive for basic biomedical research. With respect to single-photon emission computed tomography (SPECT) approaches, clinical myocardial perfusion imaging protocols are established with different 99mTc-labeled perfusion tracers; however, studies evaluating and optimizing protocols for these tracers in high-resolution pinhole SPECT in mice are lacking. This study aims at evaluating two clinically available 99mTc-labeled myocardial perfusion tracers (99mTc-sestamibi vs. 99mTc-Tetrofosmin) in mice using four different imaging protocols. Methods Adult C57BL/6 male mice were injected with 99mTc-sestamibi (MIBI) or 99mTc-Tetrofosmin (TETRO) (4 MBq/g body weight) either intravenously through the tail vein (n = 5) or retroorbitally (n = 5) or intraperitoneally (i.p.) under anesthesia (n = 3) or i.p. in an awake state (n = 3) at rest. Immediately after injection, a multi-frame single-photon emission computed tomography/computed tomography (SPECT/CT) acquisition was initiated with six subsequent time frames of 10 min each. Reconstructed images of the different protocols were assessed and compared by visual analysis by experts and by time-activity-curves generated from regions-of-interest for various organs (normalized uptake values). Results Visually assessing overall image quality, the best image quality was found for MIBI for both intravenous injection protocols, whereas TETRO only had comparable image quality after retroorbital injections. These results were confirmed by quantitative analysis where left ventricular (LV) uptake of MIBI after tail vein injections was found significantly higher for all time points accompanied with a significantly slower washout of 16% for MIBI vs. 33% for TETRO (p = 0.009) from 10 to 60 min post injection (PI). Interestingly, LV washout from 10 to 60 min PI

  18. Interrogation of multidrug resistance (MDR1) P-glycoprotein (ABCB1) expression in human pancreatic carcinoma cells: correlation of 99mTc-Sestamibi uptake with western blot analysis.

    PubMed

    Harpstrite, Scott E; Gu, Hannah; Natarajan, Radhika; Sharma, Vijay

    2014-10-01

    Histopathological studies indicate that ∼63% of pancreatic tumors express multidrug resistance (MDR1) P-glycoprotein (Pgp) and its polymorphic variants. However, Pgp expression detected at the mRNA or protein level does not always correlate with functional transport activity. Because Pgp transport activity is affected by specific mutations and the phosphorylation state of the protein, altered or less active forms of Pgp may also be detected by PCR or immunohistochemistry, which do not accurately reflect the status of tumor cell resistance. To interrogate the status of the functional expression of MDR1 Pgp in MiaPaCa-2 and PANC-1 cells, cellular transport studies using Tc-Sestamibi were performed and correlated with western blot analysis. Biochemical transport assays in human pancreatic carcinoma MiaPaCa-2 and PANC-1 cells, human epidermal carcinoma drug-sensitive KB-3-1 cells, and human breast carcinoma MCF-7 cells (negative controls), and human epidermal carcinoma drug-resistant KB-8-5 cells, human breast carcinoma stably transfected with Pgp MCF-7/MDR1Pgp cells, and liver carcinoma HepG2 cells (positive controls) were performed. Protein levels were determined using a monoclonal antibody C219. Tc-Sestamibi demonstrates accumulation in human pancreatic carcinoma MiaPaCa-2 and PANC-1 cells. Uptake profiles are not affected by treatment with LY335979, a Pgp inhibitor, and correlate with western blot analysis. These cellular transport studies indicate an absence of Pgp at a functional level in MiaPaCa-2 and PANC-1 cells. Because major pancreatic tumors originate from the pancreatic duct and Tc-Sestamibi undergoes a dominant hepatobiliary mode of excretion, it would not be a sensitive probe for imaging pancreatic adenocarcinomas. Following interrogation of the functional status of Pgp in other pancreatic carcinoma cells, chemotherapeutic drugs that are also MDR1 substrates could offer alternative therapeutics for treating pancreatic adenocarcinomas. PMID:25036383

  19. Accuracy and safety of technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile (Sestamibi) myocardial scintigraphy with high dose dipyridamole test in patients with effort angina pectoris: a multicenter study. Italian Group of Nuclear Cardiology.

    PubMed

    Parodi, O; Marcassa, C; Casucci, R; Sambuceti, G; Verna, E; Galli, M; Inglese, E; Marzullo, P; Pirelli, S; Bisi, G

    1991-11-15

    Clinical and physiologic evidence indicates that maximal coronary vasodilation is not achieved in a large number of patients with use of the standard dose of dipyridamole (0.56 mg/kg body weight over 4 min). The feasibility, safety and accuracy of technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile (Sestamibi) scintigraphy associated with intravenous high dose dipyridamole (0.56 mg/kg over 4 min followed 4 min later by an additional 0.28 mg/kg over 2 min) were evaluated in a multicenter study. Planar myocardial perfusion images were obtained at rest and after dipyridamole in 101 patients with effort chest pain and no prior myocardial infarction. High dose dipyridamole (62 patients) was used when typical chest pain or electrocardiographic (ECG) signs of ischemia, or both, did not occur during or after the standard dose (39 patients). With high dose dipyridamole, 34 patients had pain (18 patients) or ECG signs of ischemia (ST depression greater than or equal to 2 mm) (8 patients), or both (8 patients), whereas the other 28 patients had Sestamibi injection in the absence of symptoms or ECG changes. All patients underwent coronary angiography: 81 had significant coronary artery disease (greater than or equal to 50% reduction of lumen diameter) (affecting one vessel in 38, two vessels in 19 and three vessels in 24 patients) and 20 patients had normal coronary arteries. The overall sensitivity, specificity and predictive accuracy of Sestamibi scintigraphy were 81%, 90% and 83%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1834717

  20. Breast PET scan

    MedlinePlus

    ... medlineplus.gov/ency/article/007469.htm Breast PET scan To use the sharing features on this page, ... enable JavaScript. A breast positron emission tomography (PET) scan is an imaging test that uses a radioactive ...

  1. Lung gallium scan

    MedlinePlus

    ... any concerns you have about radiation with the health care provider who recommends the test. ... Usually the health care provider will recommend this scan based on ... the scan. For this reason, this test is not often done anymore.

  2. Heart PET scan

    MedlinePlus

    Heart nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Mann DL, ... A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, ...

  3. RBC nuclear scan

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003835.htm RBC nuclear scan To use the sharing features on this page, please enable JavaScript. An RBC nuclear scan uses small amounts of radioactive material to ...

  4. Bone density scan (image)

    MedlinePlus

    ... bone the higher the risk of fractures. A bone scan, along with a patient's medical history, is a ... and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and exposing ...

  5. Orbit CT scan

    MedlinePlus

    ... results may mean: Bleeding Broken eye socket bone Graves disease Infection Tumor Risks CT scans and other x- ... Livingstone; 2014:chap 66. Read More CT scan Graves disease Tumor Update Date 1/18/2015 Updated by: ...

  6. Optical scanning cryptography

    NASA Astrophysics Data System (ADS)

    Poon, Ting-Chung

    2004-01-01

    We introduce a technique called optical scanning cryptography (OSC). The technique can perform encryption on-the-fly using laser beams and can be implemented using an optical heterodyne scanning. We shall first describe the optical heterodyne scanning system and then provide some computer simulations to clarify and confirm the idea of encryption and decryption.

  7. Multipurpose binocular scanning apparatus

    NASA Technical Reports Server (NTRS)

    Chamberlain, F. R.; Parker, G. L.

    1969-01-01

    Optical gimballing apparatus directs narrow fields of view throughout solid angle approaching 4 pi steradians. Image rotation produced by scanning can be eliminated or altered by gear trains directly linked to the scanning drive assembly. It provides the basis for a binocular scanning capability.

  8. Breast-specific gamma-imaging: molecular imaging of the breast using 99mTc-sestamibi and a small-field-of-view gamma-camera.

    PubMed

    Jones, Elizabeth A; Phan, Trinh D; Blanchard, Deborah A; Miley, Abbe

    2009-12-01

    Breast-specific gamma-imaging (BSGI), also known as molecular breast imaging, is breast scintigraphy using a small-field-of-view gamma-camera and (99m)Tc-sestamibi. There are many different types of breast cancer, and many have characteristics making them challenging to detect by mammography and ultrasound. BSGI is a cost-effective, highly sensitive and specific technique that complements other imaging modalities currently being used to identify malignant lesions in the breast. Using the current Society of Nuclear Medicine guidelines for breast scintigraphy, Legacy Good Samaritan Hospital began conducting BSGI, breast scintigraphy with a breast-optimized gamma-camera. In our experience, optimal imaging has been conducted in the Breast Center by a nuclear medicine technologist. In addition, the breast radiologists read the BSGI images in correlation with the mammograms, ultrasounds, and other imaging studies performed. By modifying the current Society of Nuclear Medicine protocol to adapt it to the practice of breast scintigraphy with these new systems and by providing image interpretation in conjunction with the other breast imaging studies, our center has found BSGI to be a valuable adjunctive procedure in the diagnosis of breast cancer. The development of a small-field-of-view gamma-camera, designed to optimize breast imaging, has resulted in improved detection capabilities, particularly for lesions less than 1 cm. Our experience with this procedure has proven to aid in the clinical work-up of many of our breast patients. After reading this article, the reader should understand the history of breast scintigraphy, the pharmaceutical used, patient preparation and positioning, imaging protocol guidelines, clinical indications, and the role of breast scintigraphy in breast cancer diagnosis. PMID:19914975

  9. Is Tc-99m sestamibi scintimammography useful in the prediction of neoadjuvant chemotherapy responses in breast cancer? A systematic review and meta-analysis.

    PubMed

    Guo, Cui; Zhang, Chengpeng; Liu, Jianjun; Tong, Linjun; Huang, Gang

    2016-07-01

    To evaluate the accuracy of Tc-99m sestamibi (MIBI) scintimammography in the prediction of neoadjuvant chemotherapy response in breast cancer. 'PubMed' (MEDLINE included) and Embase database were searched for relevant publications in English. Methodological quality of the included studies was assessed with Quality Assessment of Diagnosis Accuracy Studies (QUADAS), and 'Meta-Disc' and 'Stata' software were used to determine pooled sensitivity, specificity, and diagnostic odds ratio (DOR), and construct a summary receiver-operating characteristic curve. Fourteen studies (a total of 503 individuals) fulfilled the inclusion criteria. The pooled sensitivity was 0.86 [95% confidence interval (CI): 0.78-0.92] and the pooled specificity was 0.69 (95% CI: 0.64-0.74). Pooled likelihood ratio (LRp), negative likelihood ratio (LR-), and DOR were 2.64 (95% CI: 1.81-3.85), 0.26 (95% CI: 0.15-0.46), and 12.06 (95% CI: 6.94-20.96), respectively. The area under the summary receiver-operating characteristic curve was 0.86. For the prediction of pathological complete response (10 studies included), the pooled sensitivity and specificity and DOR were 0.86 (95% CI: 0.77-0.93), 0.67 (95% CI: 0.62-0.72), and 11.43 (95% CI: 5.95-21.97). Our results indicated that Tc-99m MIBI scintimammography had acceptable sensitivity in the prediction of neoadjuvant chemotherapy response in breast cancer; however, its relatively low specificity showed that a combination of other imaging modalities would still be needed. Subgroup analysis indicated that performing early mid-treatment Tc-99m MIBI scintimammography (using the reduction rate of one or two cycles or within the first half-courses of chemotherapy compared with the baseline) was better than carrying out later (after three or more courses) or post-treatment scintimammography in the prediction of neoadjuvant chemotherapy response. PMID:26974314

  10. Pulmonary ventilation/perfusion scan

    MedlinePlus

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health ...

  11. Rapid frequency scan EPR.

    PubMed

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-08-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x, y plane decays to baseline at the end of the scan, which typically is about 5T(2) after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5T(2). However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5T(2), even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B(1), periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation. PMID:21664848

  12. Rapid Frequency Scan EPR

    PubMed Central

    Tseitlin, Mark; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x,y plane decays to baseline at the end of the scan, which typically is about 5 T2 after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5 T2. However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5 T2, even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B1, periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation. PMID:21664848

  13. Line-scanning, stage scanning confocal microscope

    NASA Astrophysics Data System (ADS)

    Carucci, John A.; Stevenson, Mary; Gareau, Daniel

    2016-03-01

    We created a line-scanning, stage scanning confocal microscope as part of a new procedure: video assisted micrographic surgery (VAMS). The need for rapid pathological assessment of the tissue on the surface of skin excisions very large since there are 3.5 million new skin cancers diagnosed annually in the United States. The new design presented here is a confocal microscope without any scanning optics. Instead, a line is focused in space and the sample, which is flattened, is physically translated such that the line scans across its face in a direction perpendicular to the line its self. The line is 6mm long and the stage is capable of scanning 50 mm, hence the field of view is quite large. The theoretical diffraction-limited resolution is 0.7um lateral and 3.7um axial. However, in this preliminary report, we present initial results that are a factor of 5-7 poorer in resolution. The results are encouraging because they demonstrate that the linear array detector measures sufficient signal from fluorescently labeled tissue and also demonstrate the large field of view achievable with VAMS.

  14. Radionucleotide scanning in osteomyelitis

    SciTech Connect

    Sachs, W.; Kanat, I.O.

    1986-07-01

    Radionucleotide bone scanning can be an excellent adjunct to the standard radiograph and clinical findings in the diagnosis of osteomyelitis. Bone scans have the ability to detect osteomyelitis far in advance of the standard radiograph. The sequential use of technetium and gallium has been useful in differentiating cellulitis and osteomyelitis. Serial scanning with technetium and gallium may be used to monitor the response of osteomyelitis to antibiotic therapy.

  15. 99mTc-Sestamibi Using a Direct Conversion Molecular Breast Imaging System to Assess Tumor Response to Neoadjuvant Chemotherapy in Women With Locally Advanced Breast Cancer

    PubMed Central

    Mitchell, David; Hruska, Carrie B.; Boughey, Judy C.; Wahner-Roedler, Dietlind L.; Jones, Katie N.; Tortorelli, Cindy; Conners, Amy Lynn; O’Connor, Michael K.

    2014-01-01

    Purpose The objective of this study was to determine the ability of breast imaging with 99mTc-sestamibi and a direct conversion–molecular breast imaging (MBI) system to predict early response to neoadjuvant chemotherapy (NAC). Methods Patients undergoing NAC for breast cancer were imaged with a direct conversion–MBI system before (baseline), at 3 to 5 weeks after onset, and after completion of NAC. Tumor size and tumor-to-background (T/B) uptake ratio measured from MBI images were compared with extent of residual disease at surgery using the residual cancer burden. Results Nineteen patients completed imaging and proceeded to surgical resection after NAC. Mean reduction in T/B ratio from baseline to 3 to 5 weeks for patients classified as RCB-0 (no residual disease), RCB-1 and RCB-2 combined, and RCB-3 (extensive residual disease) was 56% (SD, 0.20), 28% (SD, 0.20), and 4% (SD, 0.15), respectively. The reduction in the RCB-0 group was significantly greater than in RCB-1/2 (P = 0.036) and RCB-3 (P = 0.001) groups. The area under the receiver operator characteristic curve for determining the presence or absence of residual disease was 0.88. Using a threshold of 50% reduction in T/B ratio at 3 to 5 weeks, MBI predicted presence of residual disease at surgery with a diagnostic accuracy of 89.5% (95% confidence interval [CI], 0.64%–0.99%), sensitivity of 92.3% (95% CI, 0.74%–0.99%), and specificity of 83.3% (95% CI, 0.44%–0.99%). The reduction in tumor size at 3 to 5 weeks was not statistically different between RCB groups. Conclusions Changes in T/B ratio on MBI images performed at 3 to 5 weeks following initiation of NAC were accurate at predicting the presence or absence of residual disease at NAC completion. PMID:24152645

  16. Environmental Scanning Report.

    ERIC Educational Resources Information Center

    Truckee Meadows Community Coll., Sparks, NV.

    This report describes Truckee Meadows Community College's (Nevada) environmental scanning process and results. The college decided that environmental scanning and forecasting techniques should be used to plan for both short-term and long-term external factors that impact programs, enrollment, and budgets. Strategic goals include: (1) keeping pace…

  17. Getting a CAT Scan

    MedlinePlus

    ... Here's Help White House Lunch Recipes Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  18. Optical Scanning Applications.

    ERIC Educational Resources Information Center

    Wagner, Hans

    The successful use of optical scanning at the University of the Pacific (UOP) indicates that such techniques can simplify a number of administrative data processing tasks. Optical scanning is regularly used at UOP to assist with data processing in the areas of admissions, registration and grade reporting and also has applications for other tasks…

  19. Laser Scanning In Inspection

    NASA Astrophysics Data System (ADS)

    West, Patricia; Baker, Lionel R.

    1989-03-01

    This paper is a review of the applications of laser scanning in inspection. The reasons for the choice of a laser in flying spot scanning and the optical properties of a laser beam which are of value in a scanning instrument will be given. The many methods of scanning laser beams in both one and two dimensions will be described. The use of one dimensional laser scanners for automatic surface inspection for transmitting and reflective products will be covered in detail, with particular emphasis on light collection techniques. On-line inspection applications which will be mentioned include: photographic film web, metal strip products, paper web, glass sheet, car body paint surfaces and internal cylinder bores. Two dimensional laser scanning is employed in applications where increased resolution, increased depth of focus, and better contrast are required compared with conventional vidicon TV or solid state array cameras. Such examples as special microscope laser scanning systems and a TV compatible system for use in restricted areas of a nuclear reactor will be described. The technical and economic benefits and limitations of laser scanning video systems will be compared with conventional TV and CCD array devices.

  20. Virtual slit scanning microscopy.

    PubMed

    Fiolka, Reto; Stemmer, Andreas; Belyaev, Yury

    2007-12-01

    We present a novel slit scanning confocal microscope with a CCD camera image sensor and a virtual slit aperture for descanning that can be adjusted during post-processing. A very efficient data structure and mathematical criteria for aligning the virtual aperture guarantee the ease of use. We further introduce a method to reduce the anisotropic lateral resolution of slit scanning microscopes. System performance is evaluated against a spinning disk confocal microscope on identical specimens. The virtual slit scanning microscope works as the spinning disk type and outperforms on thick specimens. PMID:17891411

  1. Reproducibility of area at risk assessment in acute myocardial infarction by T1- and T2-mapping sequences in cardiac magnetic resonance imaging in comparison to Tc99m-sestamibi SPECT.

    PubMed

    Langhans, Birgit; Nadjiri, Jonathan; Jähnichen, Christin; Kastrati, Adnan; Martinoff, Stefan; Hadamitzky, Martin

    2014-10-01

    Area at risk (AAR) is an important parameter for the assessment of the salvage area after revascularization in acute myocardial infarction (AMI). By combining AAR assessment by T2-weighted imaging and scar quantification by late gadolinium enhancement imaging cardiovascular magnetic resonance (CMR) offers a promising alternative to the "classical" modality of Tc99m-sestamibi single photon emission tomography (SPECT). Current T2 weighted sequences for edema imaging in CMR are limited by low contrast to noise ratios and motion artifacts. During the last years novel CMR imaging techniques for quantification of acute myocardial injury, particularly the T1-mapping and T2-mapping, have attracted rising attention. But no direct comparison between the different sequences in the setting of AMI or a validation against SPECT has been reported so far. We analyzed 14 patients undergoing primary coronary revascularization in AMI in whom both a pre-intervention Tc99m-sestamibi-SPECT and CMR imaging at a median of 3.4 (interquartile range 3.3-3.6) days after the acute event were performed. Size of AAR was measured by three different non-contrast CMR techniques on corresponding short axis slices: T2-weighted, fat-suppressed turbospin echo sequence (TSE), T2-mapping from T2-prepared balanced steady state free precession sequences (T2-MAP) and T1-mapping from modified look locker inversion recovery (MOLLI) sequences. For each CMR sequence, the AAR was quantified by appropriate methods (absolute values for mapping sequences, comparison with remote myocardium for other sequences) and correlated with Tc99m-sestamibi-SPECT. All measurements were performed on a 1.5 Tesla scanner. The size of the AAR assessed by CMR was 28.7 ± 20.9 % of left ventricular myocardial volume (%LV) for TSE, 45.8 ± 16.6 %LV for T2-MAP, and 40.1 ± 14.4 %LV for MOLLI. AAR assessed by SPECT measured 41.6 ± 20.7 %LV. Correlation analysis revealed best correlation with SPECT for T2-MAP at a T2-threshold of 60 ms

  2. Leg MRI scan

    MedlinePlus

    ... imaging - leg; Magnetic resonance imaging - lower extremity; MRI - ankle; Magnetic resonance imaging - ankle; MRI - femur; MRI - leg ... or bone scan Birth defects of the leg, ankle, or foot Bone pain and fever Broken bone ...

  3. Fiber-Scanned Microdisplays

    NASA Technical Reports Server (NTRS)

    Crossman-Bosworth, Janet; Seibel, Eric

    2010-01-01

    Helmet- and head-mounted display systems, denoted fiber-scanned microdisplays, have been proposed to provide information in an "augmented reality" format (meaning that the information would be optically overlaid on the user's field of view).

  4. Knee MRI scan

    MedlinePlus

    ... magnetic resonance imaging) scan uses energy from strong magnets to create pictures of the knee joint and ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  5. Leg MRI scan

    MedlinePlus

    ... resonance imaging) scan of the leg uses strong magnets to create pictures of the leg. This may ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  6. Cervical MRI scan

    MedlinePlus

    ... magnetic resonance imaging) scan uses energy from strong magnets to create pictures of the part of the ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  7. Arm MRI scan

    MedlinePlus

    ... arm MRI (magnetic resonance imaging) scan uses strong magnets to create pictures of the upper and lower ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  8. Pediatric CT Scans

    Cancer.gov

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  9. CT scan (image)

    MedlinePlus

    CT stands for computerized tomography. In this procedure, a thin X-ray beam is rotated around the ... D image of a section through the body. CT scans are very detailed and provide excellent information ...

  10. Brain PET scan

    MedlinePlus

    ... tests, such as magnetic resonance imaging ( MRI ) and computed tomography ( CT ) scans only reveal the structure of the ... a PET/CT. Alternative Names ... PT, Rijntjes M, Weiller C. Neuroimaging: Functional neuroimaging. In: Daroff RB, Fenichel GM, Jankovic ...

  11. Lumbar MRI scan

    MedlinePlus

    ... resonance imaging (MRI) scan uses energy from strong magnets to create pictures of the lower part of ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  12. The Scanning Optical Microscope.

    ERIC Educational Resources Information Center

    Sheppard, C. J. R.

    1978-01-01

    Describes the principle of the scanning optical microscope and explains its advantages over the conventional microscope in the improvement of resolution and contrast, as well as the possibility of producing a picture from optical harmonies generated within the specimen.

  13. Chest CT Scan

    MedlinePlus

    ... pictures to create a very detailed, three-dimensional (3D) model of organs. Sometimes, a substance called contrast dye is injected into a vein in your arm for the CT scan. This substance highlights areas in your chest, which ...

  14. Slow Scan Telemedicine

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Originally developed under contract for NASA by Ball Bros. Research Corporation for acquiring visual information from lunar and planetary spacecraft, system uses standard closed circuit camera connected to a device called a scan converter, which slows the stream of images to match an audio circuit, such as a telephone line. Transmitted to its destination, the image is reconverted by another scan converter and displayed on a monitor. In addition to assist scans, technique allows transmission of x-rays, nuclear scans, ultrasonic imagery, thermograms, electrocardiograms or live views of patient. Also allows conferencing and consultation among medical centers, general practitioners, specialists and disease control centers. Commercialized by Colorado Video, Inc., major employment is in business and industry for teleconferencing, cable TV news, transmission of scientific/engineering data, security, information retrieval, insurance claim adjustment, instructional programs, and remote viewing of advertising layouts, real estate, construction sites or products.

  15. Ultrafast scanning probe microscopy

    SciTech Connect

    Botkin, D.; Weiss, S.; Ogletree, D.F.; Salmeron, M.; Chemla, D.S.

    1994-01-01

    The authors have developed a general technique which combines the temporal resolution of ultrafast laser spectroscopy with the spatial resolution of scanned probe microscopy (SPM). Using this technique with scanning tunneling microscopy (STM), they have obtained simultaneous 2 ps time resolution and 50 {angstrom} spatial resolution. This improves the time resolution currently attainable with STM by nine orders of magnitude. The potential of this powerful technique for studying ultrafast dynamical phenomena on surfaces with atomic resolution is discussed.

  16. Wide scanning spherical antenna

    NASA Technical Reports Server (NTRS)

    Shen, Bing (Inventor); Stutzman, Warren L. (Inventor)

    1995-01-01

    A novel method for calculating the surface shapes for subreflectors in a suboptic assembly of a tri-reflector spherical antenna system is introduced, modeled from a generalization of Galindo-Israel's method of solving partial differential equations to correct for spherical aberration and provide uniform feed to aperture mapping. In a first embodiment, the suboptic assembly moves as a single unit to achieve scan while the main reflector remains stationary. A feed horn is tilted during scan to maintain the illuminated area on the main spherical reflector fixed throughout the scan thereby eliminating the need to oversize the main spherical reflector. In an alternate embodiment, both the main spherical reflector and the suboptic assembly are fixed. A flat mirror is used to create a virtual image of the suboptic assembly. Scan is achieved by rotating the mirror about the spherical center of the main reflector. The feed horn is tilted during scan to maintain the illuminated area on the main spherical reflector fixed throughout the scan.

  17. Scanning Probe Microscopy and Spectroscopy

    NASA Astrophysics Data System (ADS)

    Wiesendanger, Roland

    1994-09-01

    Preface; List of acronyms; Introduction; Part I. Experimental Methods and Theoretical Background of Scanning Probe Microscopy and Spectroscopy: 1. Scanning tunnelling microscopy; 2. Scanning force microscopy; 3. Related scanning probe techniques; Part II. Applications of Scanning Probe Microscopy and Spectroscopy: 4. Condensed matter physics; 5. Chemistry; 6. Organic materials; 7. Metrology and standards; 8. Nanotechnology; References; Index.

  18. Shipborne hydrographic laser scanning

    NASA Astrophysics Data System (ADS)

    Pfennigbauer, Martin; Rieger, Peter; Schaich, Martin

    2011-11-01

    Applications like hydro-archeology, hydrobiology, or hydraulic engineering sometimes require accurate surveying of submerged areas with point densities usually only achieved with mobile or terrestrial laser scanning. For navigable waterbodies, hydrographic laser scanning from a floating platform represents a viable solution. RIEGL's new hydrographic laser scanner VQ-820-G with its exceptionally high measurement rate of up to 110,000 net measurements per second and its small laser footprint is optimally suited for such applications. We present results from a measurement campaign surveying prehistoric lake dwellings at Lake Constance in Germany. While the aim of typical hydrographic laser scanning applications is to roughly acquire the ground's shape and structure, in this case it was tried to determine the exact position, shape, and attitude of the remainders of the piles. The special requirements with respect to mission planning and data processing are discussed and the performance of the laser scanner is assessed.

  19. Femtosecond scanning tunneling microscope

    SciTech Connect

    Taylor, A.J.; Donati, G.P.; Rodriguez, G.; Gosnell, T.R.; Trugman, S.A.; Some, D.I.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). By combining scanning tunneling microscopy with ultrafast optical techniques we have developed a novel tool to probe phenomena on atomic time and length scales. We have built and characterized an ultrafast scanning tunneling microscope in terms of temporal resolution, sensitivity and dynamic range. Using a novel photoconductive low-temperature-grown GaAs tip, we have achieved a temporal resolution of 1.5 picoseconds and a spatial resolution of 10 nanometers. This scanning tunneling microscope has both cryogenic and ultra-high vacuum capabilities, enabling the study of a wide range of important scientific problems.

  20. Vector generator scan converter

    DOEpatents

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  1. Vector generator scan converter

    DOEpatents

    Moore, James M.; Leighton, James F.

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  2. Adaptive Optical Scanning Holography.

    PubMed

    Tsang, P W M; Poon, Ting-Chung; Liu, J-P

    2016-01-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably. PMID:26916866

  3. Scanning computed confocal imager

    DOEpatents

    George, John S.

    2000-03-14

    There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

  4. Adaptive Optical Scanning Holography

    PubMed Central

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-01-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably. PMID:26916866

  5. Teratoma - MRI scan (image)

    MedlinePlus

    This MRI scan shows a tumor (teratoma) at the base of the spine (seen on the left lower edge of the screen), located in the sacrum and coccyx (sacrococcygeal) area. Teratomas are present at birth and may contain hair, teeth, and other tissues.

  6. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, Shimon; Chemla, Daniel S.; Ogletree, D. Frank; Botkin, David

    1995-01-01

    An ultrafast scanning probe microscopy method for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample.

  7. Gallbladder radionuclide scan

    MedlinePlus

    ... please enable JavaScript. Gallbladder radionuclide scan is a test that uses radioactive material to check gallbladder function. It is also used to look for bile duct blockage or leak. How the Test is Performed The health care provider will inject ...

  8. Skimming & Scanning. Advanced Level.

    ERIC Educational Resources Information Center

    Fry, Edward B.

    Part of a series intended to develop essential specialized reading skills, this text/workbook is designed to provide instruction and practice in skimming and scanning for students reading at the seventh through tenth grade reading levels, considered the advanced level. Part 1 of the book deals with skimming. A lesson defines skimming (the rapid…

  9. Scan This Book!

    ERIC Educational Resources Information Center

    Albanese, Andrew Richard

    2007-01-01

    In this article, the author presents an interview with Brewster Kahle, leader of the Open Content Alliance (OCA). OCA book scan program is an alternative to Google's library project that aims to make books accessible online. In this interview, Kahle discusses his views on the challenges of getting books on the Web, on Google's library…

  10. THE 2016 ENVIRONMENTAL SCAN.

    PubMed

    O'Dell, Gene

    2015-09-01

    Every year, the American Hospital Association compiles the Environmental Scan to provide hospital leaders with insight and information about market forces that are likely to affect the health care field. One common theme this year is the pace of change. PMID:26495611

  11. Environmental Scanning Report, 1992.

    ERIC Educational Resources Information Center

    Yao, Min

    In response to the change in the provincial economy from natural-resource-based industries to service-oriented industries, Vancouver Community College (VCC) in British Columbia (BC) conducted an environmental scan of the social and economic trends in the college's service region that will most likely affect prospective students' educational and…

  12. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, S.; Chemla, D.S.; Ogletree, D.F.; Botkin, D.

    1995-05-16

    An ultrafast scanning probe microscopy method is described for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample. 6 Figs.

  13. Lung Ventilation/Perfusion Scan

    MedlinePlus

    ... from the NHLBI on Twitter. What Is a Lung Ventilation/Perfusion Scan? A lung ventilation/perfusion scan, or VQ scan, is a ... that measures air and blood flow in your lungs. A VQ scan most often is used to ...

  14. Scanning thermal plumes

    NASA Technical Reports Server (NTRS)

    Scarpace, F. L.; Madding, R. P.; Green, T., III

    1975-01-01

    Over a three-year period 800 thermal line scans of power plant plumes were made by an airborne scanner, with ground truth measured concurrently at the plants. Computations using centered finite differences in the thermal scanning imagery show a lower bound in the horizontal temperature gradient in excess of 1.6 C/m. Gradients persist to 3 m below the surface. Vector plots of the velocity of thermal fronts are constructed by tracing the front motion in successive thermal images. A procedure is outlined for the two-point ground calibration of a thermal scanner from an equation describing the scanner signal and the voltage for two known temperatures. The modulation transfer function is then calculated by input of a thermal step function and application of digital time analysis techniques using Fast Fourier Transforms to the voltage output. Field calibration tests are discussed. Data accuracy is limited by the level of ground truth effort chosen.

  15. Fly-scan ptychography

    DOE PAGESBeta

    Huang, Xiaojing; Lauer, Kenneth; Clark, Jesse N.; Xu, Weihe; Nazaretski, Evgeny; Harder, Ross; Robinson, Ian K.; Chu, Yong S.

    2015-03-13

    We report an experimental ptychography measurement performed in fly-scan mode. With a visible-light laser source, we demonstrate a 5-fold reduction of data acquisition time. By including multiple mutually incoherent modes into the incident illumination, high quality images were successfully reconstructed from blurry diffraction patterns. This approach significantly increases the throughput of ptychography, especially for three-dimensional applications and the visualization of dynamic systems.

  16. Scanning micro-sclerometer

    DOEpatents

    Oliver, Warren C.; Blau, Peter J.

    1994-01-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch.

  17. Fly-scan ptychography

    PubMed Central

    Huang, Xiaojing; Lauer, Kenneth; Clark, Jesse N.; Xu, Weihe; Nazaretski, Evgeny; Harder, Ross; Robinson, Ian K.; Chu, Yong S.

    2015-01-01

    We report an experimental ptychography measurement performed in fly-scan mode. With a visible-light laser source, we demonstrate a 5-fold reduction of data acquisition time. By including multiple mutually incoherent modes into the incident illumination, high quality images were successfully reconstructed from blurry diffraction patterns. This approach significantly increases the throughput of ptychography, especially for three-dimensional applications and the visualization of dynamic systems. PMID:25766519

  18. Scanning micro-sclerometer

    DOEpatents

    Oliver, W.C.; Blau, P.J.

    1994-11-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch. 2 figs.

  19. Scanning Tomographic Acoustic Microscopy

    NASA Astrophysics Data System (ADS)

    Wade, G.; Meyyappan, A.

    1988-07-01

    The technology for "seeing" with sound has an important and interesting history. Some of nature's creatures have been using sound waves for many millenia to image otherwise unobservable objects. The human species, lacking this natural ability, have overcome this deficiency by developing several different ultrasonic imaging techniques. acoustic microscopy is one such technique, which produces high resolution images of detailed structure of small objects in a non-destructive fashion. Two types of acoustic microscopes have evolved for industrial exploitation. They are the scanning laser acoustic microscope (SLAM) and the scanning acoustic microscope (SAM). In this paper, we review the principles of SLAM and describe how we use elements of SLAM to realize the scanning tomographic acoustic microscope (STAM). We describe the data acquisition process and the image reconstruction procedure. We also describe techniques to obtain projection data from different angles of wave incidence enabling us to reconstruct different planes of a complex specimen tomo-graphically. Our experimental results show that STAM is capable of producing high-quality high-resolution subsurface images.

  20. Scanning tomographic acoustic microscopy

    NASA Astrophysics Data System (ADS)

    Lee, Hua

    2002-11-01

    This paper provides an overview of the design and development of the scanning tomographic acoustic microscopy (STAM). This research effort spans over a period of more than 12 years, which successfully elevated the acoustic microscopy from the traditional intensity-mapping mode to the level of holographic and tomographic imaging. The tomographic imaging capability of STAM was developed on the platform of the scanning laser acoustic microscope (SLAM), which operates in a coherent transmission mode with plane-wave illumination and scanning laser wavefield detection. The image formation techniques were based on the backward propagation method implemented in the plane-to-plane format. In this paper, the key elements of the design and development, including the modification of the data-acquisition hardware, implementation of image reconstruction algorithms for multiple-frequency and multiple-angle tomography, and the high-precision phase-correction and image registration techniques for the superposition of coherent sub-images, will be discussed. Results of full-scale experiments will also be included to demonstrate the capability of holographic and tomographic image formation in microscopic scale.

  1. Scanning holographic lidar telescope

    NASA Technical Reports Server (NTRS)

    Schwemmer, Geary K.; Wilkerson, Thomas D.

    1993-01-01

    We have developed a unique telescope for lidar using a holographic optical element (HOE) as the primary optic. The HOE diffracts 532 nm laser backscatter making a 43 deg angle with a normal to its surface to a focus located 130 cm along the normal. The field of view scans a circle as the HOE rotates about the normal. The detector assembly and baffling remain stationary, compared to conventional scanning lidars in which the entire telescope and detector assembly require steering, or which use a large flat steerable mirror in front of the telescope to do the pointing. The spectral bandpass of our HOE is 50 nm (FWHM). Light within that bandpass is spectrally dispersed at 0.6 nm/mm in the focal plane. An aperture stop reduces the bandpass of light reaching the detector from one direction to 1 nm while simultaneously reducing the field of view to 1 mrad. Wavelengths outside the 50 nm spectral bandpass pass undiffracted through HOE to be absorbed by a black backing. Thus, the HOE combines three functions into one optic: the scanning mirror, the focusing mirror, and a narrowband filter.

  2. Forensic Scanning Electron Microscope

    NASA Astrophysics Data System (ADS)

    Keeley, R. H.

    1983-03-01

    The scanning electron microscope equipped with an x-ray spectrometer is a versatile instrument which has many uses in the investigation of crime and preparation of scientific evidence for the courts. Major applications include microscopy and analysis of very small fragments of paint, glass and other materials which may link an individual with a scene of crime, identification of firearms residues and examination of questioned documents. Although simultaneous observation and chemical analysis of the sample is the most important feature of the instrument, other modes of operation such as cathodoluminescence spectrometry, backscattered electron imaging and direct x-ray excitation are also exploited. Marks on two bullets or cartridge cases can be compared directly by sequential scanning with a single beam or electronic linkage of two instruments. Particles of primer residue deposited on the skin and clothing when a gun is fired can be collected on adhesive tape and identified by their morphology and elemental composition. It is also possible to differentiate between the primer residues of different types of ammunition. Bullets may be identified from the small fragments left behind as they pass through the body tissues. In the examination of questioned documents the scanning electron microscope is used to establish the order in which two intersecting ink lines were written and to detect traces of chemical markers added to the security inks on official documents.

  3. Descreening of scanned images

    NASA Astrophysics Data System (ADS)

    Kurilin, Ilya V.; Safonov, Ilia V.; Lee, HoKeun; Kim, Sang Ho

    2010-01-01

    Screen or halftone pattern appears on the majority of images printed on electrophotographic and ink-jet printers as well as offset machines. When such halftoned image is scanned, a noisy effect called a Moiré pattern often appears on the image. There are plenty of methods proposed for descreening of images. Common way is adaptive smoothing of scanned images. However the descreening techniques face the following dilemma: deep screen reduction and restoration of contone images leads to blurring of sharp edges of text and other graphics primitives, on the other hand insufficient smoothing keeps screen in halftoned areas. We propose novel descreening algorithm that is primarily intended for preservation of sharpness and contrast of text edges and for restoration contone images from halftone ones accurately. Proposed technique for descreening of scanned images comprises five steps. The first step is decrease of edge transition slope length via local tone mapping with ordering; it is carried out before adaptive smoothing, and it allows better preservation of edges. Adaptive low-pass filter applies simplified idea of Non-Local Means filter for area classification; similarity is calculated between central block of window and different adjacent block that is selected randomly. If similarity is high then current pixel relates to flat region, otherwise pixel relates to edge region. For prevention of edges blurring, flat regions are smoothed stronger than edge regions. By random selection of blocks we avoid the computational overhead related to excessive directional edge detection. Final three stages include additional decrease of edge transition slope length using local tone mapping, increase of local contrast via modified unsharp mask filter, that uses bilateral filter with special edge-stop function for modest smoothing of edges, and global contrast stretching. These stages are intended to compensate decreasing of sharpness and contrast due to low-pass filtering, it allows

  4. Scanning radiographic apparatus

    SciTech Connect

    Albert, R.D.

    1980-04-01

    Visual display of dental, medical or other radiographic images is realized with an x-ray tube in which an electron beam is scanned through an x-y raster pattern on a broad anode plate, the scanning being synchronized with the x-y sweep signals of a cathode ray tube display and the intensity signal for the display being derived from a small x-ray detector which receives x-rays that have passed through the subject to be imaged. Positioning and support of the detector are provided for by disposing the detector in a probe which may be attached to the x-ray tube at any of a plurality of different locations and by providing a plurality of such probes of different configuration in order to change focal length, to accommodate to different detector placements relative to the subject, to enhance patient comfort and to enable production of both periapical images and wider angle pantomographic images. High image definition with reduced radiation dosage is provided for by a lead glass collimator situated between the x-ray tube and subject and having a large number of spaced-apart minute radiation transmissive passages convergent on the position of the detector. Releasable mounting means enable changes of collimator in conjunction with changes of the probe to change focal length. A control circuit modifies the x-y sweep signals applied to the x-ray tube and modulates electron beam energy and current in order to correct for image distortions and other undesirable effects which can otherwise be present in a scanning x-ray system.

  5. Scans Solo: A One-Person Environmental Scanning Process.

    ERIC Educational Resources Information Center

    Clagett, Craig A.

    An effective environmental scan will improve the quality of community college planning and decision making by alerting institutional leaders to the challenges and opportunities in the environment. Scanning can be done in three ways: (1) establishing a scanning committee to gather and synthesize information to guide planning; (2) sponsoring a…

  6. A-Scan Echoencephalography

    PubMed Central

    White, D. Naldrett

    1966-01-01

    The technique of A-scan echoencephalography is criticized in so far as it lacks objectivity and reproducibility. In the author's laboratory, the M-echo, being of higher amplitude than other intracranial echoes, is distinguished from other echoes by an averaging technique—a time exposure. Double transmission pulses indicate the theoretical position of echoes from the true mid-line and superimposition of far-side echoes ensures that the transducers are correctly aligned. The very considerable difficulties in identifying the anatomical structures giving rise to other echoes seen within the skull are outlined. They are largely due to variations in the reflected energy, depending upon the shape and orientation and position of the various interfaces with respect to the ultrasonic beam. Despite these difficulties and limitations, A-scan echoencephalography appears to have an important part to play as a simple, safe and quick form of neurological examination, if the technique can be made truly objective. ImagesFig. 1Fig. 9Fig. 10 PMID:5901162

  7. Ultrafast scanning tunneling microscopy

    SciTech Connect

    Botkin, D.A. |

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  8. Free Motion Scanning System

    SciTech Connect

    Sword, Charles K.

    1998-06-18

    The present invention relates to an ultrasonic scanner and method for the imaging of a part surface, the scanner comprising: a probe assembly spaced apart from the surface including at least two tracking signals for emitting electromagnetic radiation and a transmitter for emitting ultrasonic waves onto a surface in order to induce at least a portion of said waves to be reflected from the surface, at least one detector for receiving the electromagnetic radiation wherein the detector is positioned to receive said radiation from the tracking signals, an analyzing means for recognizing a three-dimensional location of the tracking signals based on said emitted electromagnetic radiation, a differential conversion means for generating an output signal representative of the waveform of the reflected waves, and a means for relating said tracking signal location with the output signal and projecting an image of the resulting data. The scanner and method are particularly useful to acquire ultrasonic inspection data by scanning the probe-over a complex part surface in an arbitrary scanning pattern.

  9. Free motion scanning system

    DOEpatents

    Sword, Charles K.

    2000-01-01

    The present invention relates to an ultrasonic scanner system and method for the imaging of a part system, the scanner comprising: a probe assembly spaced apart from the surface of the part including at least two tracking signals for emitting radiation and a transmitter for emitting ultrasonic waves onto a surface in order to induce at least a portion of the waves to be reflected from the part, at least one detector for receiving the radiation wherein the detector is positioned to receive the radiation from the tracking signals, an analyzer for recognizing a three-dimensional location of the tracking signals based on the emitted radiation, a differential converter for generating an output signal representative of the waveform of the reflected waves, and a device such as a computer for relating said tracking signal location with the output signal and projecting an image of the resulting data. The scanner and method are particularly useful to acquire ultrasonic inspection data by scanning the probe over a complex part surface in an arbitrary scanning pattern.

  10. The Scanning Process: Getting Started.

    ERIC Educational Resources Information Center

    Renfro, William L.; Morrison, James L.

    1983-01-01

    Scanning the external environment will become more essential to colleges in the coming decade. Developing an environmental scanning system can identify important emerging issues that may constitute either threats or opportunities. The organizational features of a mature scanning process are described. (MLW)

  11. Scanning Electrochemical Microscopy

    NASA Astrophysics Data System (ADS)

    Amemiya, Shigeru; Bard, Allen J.; Fan, Fu-Ren F.; Mirkin, Michael V.; Unwin, Patrick R.

    2008-07-01

    This review describes work done in scanning electrochemical microscopy (SECM) since 2000 with an emphasis on new applications and important trends, such as nanometer-sized tips. SECM has been adapted to investigate charge transport across liquid/liquid interfaces and to probe charge transport in thin films and membranes. It has been used in biological systems like single cells to study ion transport in channels, as well as cellular and enzyme activity. It is also a powerful and useful tool for the evaluation of the electrocatalytic activities of different materials for useful reactions, such as oxygen reduction and hydrogen oxidation. SECM has also been used as an electrochemical tool for studies of the local properties and reactivity of a wide variety of materials, including metals, insulators, and semiconductors. Finally, SECM has been combined with several other nonelectrochemical techniques, such as atomic force microscopy, to enhance and complement the information available from SECM alone.

  12. A scanning cavity microscope

    PubMed Central

    Mader, Matthias; Reichel, Jakob; Hänsch, Theodor W.; Hunger, David

    2015-01-01

    Imaging the optical properties of individual nanosystems beyond fluorescence can provide a wealth of information. However, the minute signals for absorption and dispersion are challenging to observe, and only specialized techniques requiring sophisticated noise rejection are available. Here we use signal enhancement in a high-finesse scanning optical microcavity to demonstrate ultra-sensitive imaging. Harnessing multiple interactions of probe light with a sample within an optical resonator, we achieve a 1,700-fold signal enhancement compared with diffraction-limited microscopy. We demonstrate quantitative imaging of the extinction cross-section of gold nanoparticles with a sensitivity less than 1 nm2; we show a method to improve the spatial resolution potentially below the diffraction limit by using higher order cavity modes, and we present measurements of the birefringence and extinction contrast of gold nanorods. The demonstrated simultaneous enhancement of absorptive and dispersive signals promises intriguing potential for optical studies of nanomaterials, molecules and biological nanosystems. PMID:26105690

  13. Telescopic horizon scanning.

    PubMed

    Koenderink, Jan

    2014-12-20

    The problem of "distortionless" viewing with terrestrial telescopic systems (mainly "binoculars") remains problematic. The so called "globe effect" is only partially counteracted in modern designs. Theories addressing the phenomenon have never reached definitive closure. In this paper, we show that exact distortionless viewing with terrestrial telescopic systems is not possible in general, but that it is in principle possible in-very frequent in battle field and marine applications-the case of horizon scanning. However, this involves cylindrical optical elements. For opto-electronic systems, a full solution is more readily feasible. The solution involves a novel interpretation of the relevant constraints and objectives. For final design decisions, it is not necessary to rely on a corpus of psychophysical (or ergonomic) data, although one has to decide whether the instrument is intended as an extension of the eye or as a "pictorial" device. PMID:25608206

  14. A scanning cavity microscope.

    PubMed

    Mader, Matthias; Reichel, Jakob; Hänsch, Theodor W; Hunger, David

    2015-01-01

    Imaging the optical properties of individual nanosystems beyond fluorescence can provide a wealth of information. However, the minute signals for absorption and dispersion are challenging to observe, and only specialized techniques requiring sophisticated noise rejection are available. Here we use signal enhancement in a high-finesse scanning optical microcavity to demonstrate ultra-sensitive imaging. Harnessing multiple interactions of probe light with a sample within an optical resonator, we achieve a 1,700-fold signal enhancement compared with diffraction-limited microscopy. We demonstrate quantitative imaging of the extinction cross-section of gold nanoparticles with a sensitivity less than 1 nm(2); we show a method to improve the spatial resolution potentially below the diffraction limit by using higher order cavity modes, and we present measurements of the birefringence and extinction contrast of gold nanorods. The demonstrated simultaneous enhancement of absorptive and dispersive signals promises intriguing potential for optical studies of nanomaterials, molecules and biological nanosystems. PMID:26105690

  15. Quadrature wavelength scanning interferometry.

    PubMed

    Moschetti, Giuseppe; Forbes, Alistair; Leach, Richard K; Jiang, Xiang; O'Connor, Daniel

    2016-07-10

    A novel method to double the measurement range of wavelength scanning interferometery (WSI) is described. In WSI the measured optical path difference (OPD) is affected by a sign ambiguity, that is, from an interference signal it is not possible to distinguish whether the OPD is positive or negative. The sign ambiguity can be resolved by measuring an interference signal in quadrature. A method to obtain a quadrature interference signal for WSI is described, and a theoretical analysis of the advantages is reported. Simulations of the advantages of the technique and of signal errors due to nonideal quadrature are discussed. The analysis and simulation are supported by experimental measurements to show the improved performances. PMID:27409307

  16. Adaptive scanning probe microscopies

    SciTech Connect

    Swartzentruber, B.S.; Bouchard, A.M.; Osbourn, G.C.

    1997-02-01

    This work is comprised of two major sections. In the first section the authors develop multivariate image classification techniques to distinguish and identify surface electronic species directly from multiple-bias scanning tunneling microscope (STM) images. Multiple measurements at each site are used to distinguish and categorize inequivalent electronic or atomic species on the surface via a computerized classification algorithm. Then, comparison with theory or other suitably chosen experimental data enables the identification of each class. They demonstrate the technique by analyzing dual-polarity constant-current topographs of the Ge(111) surface. Just two measurements, negative- and positive-bias topography height, permit pixels to be separated into seven different classes. Labeling four of the classes as adatoms, first-layer atoms, and two inequivalent rest-atom sites, they find excellent agreement with the c(2 x 8) structure. The remaining classes are associated with structural defects and contaminants. This work represents a first step toward developing a general electronic/chemical classification and identification tool for multivariate scanning probe microscopy imagery. In the second section they report measurements of the diffusion of Si dimers on the Si(001) surface at temperatures between room temperature and 128 C using a novel atom-tracking technique that can resolve every diffusion event. The atom tracker employs lateral-positioning feedback to lock the STM probe tip into position above selected atoms with sub-Angstrom precision. Once locked the STM tracks the position of the atoms as they migrate over the crystal surface. By tracking individual atoms directly, the ability of the instrument to measure dynamic events is increased by a factor of {approximately} 1,000 over conventional STM imaging techniques.

  17. Earth observing scanning polarimeter

    NASA Technical Reports Server (NTRS)

    Travis, Larry

    1993-01-01

    Climate forcing by tropospheric aerosols is receiving increased attention because of the realization that the climate effects may be large, while our knowledge of global aerosol characteristics and temporal changes is very poor. Tropospheric aerosols cause a direct radiative forcing due simply to their scattering and absorption of solar radiation, as well as an indirect effect as cloud condensation nuclei which can modify the shortwave reflectivity of clouds. Sulfate aerosols tend to increase planetary albedo through both the direct and indirect effects; a cooling due to anthropogenic sulfate aerosols has been estimated of order 1 W/sq m, noting that this is similar in magnitude to the present anthropogenic greenhouse gas warming. Other aerosols, including those from biomass burning and wind-blown desert dust are also of potential climatic importance. At present, the only global monitoring of tropospheric aerosols is a NOAA operational product, aerosol optical thickness, obtained using channel-1 (0.58-0.68 mu m) radiances from the AVHRR. With this single channel radiance data, one must use an approach which is based on the inferred excess of reflected radiance owing to scattering by the aerosols over that expected from theoretical calculations. This approach is suited only for situations where the surface has a low albedo that is well known a priori. Thus, the NOAA operational product is restricted to coverage over the ocean at AVHRR scan angles well away from sun glint, and aerosol changes are subject to confusion with changes caused by either optically thin or subpixel clouds. Because optically thin aerosols have only a small effect on the radiance, accurate measurements for optical thickness less than 0.1 (which is a typical background level) are precluded. Moreover, some of the largest and most important aerosol changes are expected over land. The Earth Observing Scanning Polarimeter (EOSP) instrument, based upon design heritage and analysis techniques

  18. GPR scan assessment

    NASA Astrophysics Data System (ADS)

    Abbas, Abbas M.; Salah, Hany; Massoud, Usama; Fouad, Mona; Abdel-Hafez, Mahmoud

    2015-06-01

    Mekaad Radwan monument is situated in the neighborhood of Bab Zuweila in the historical Cairo, Egypt. It was constructed at the middle XVII century (1635 AD). The building has a rectangle shape plan (13 × 6 m) with the longitudinal sides approximately WNW-ESE. It comprises three storages namely; the ground floor; the opened floor (RADWAN Bench) and the living floor with a total elevation of 15 m above the street level. The building suffers from severe deterioration phenomena with patterns of damage which have occurred over time. These deterioration and damages could be attributed to foundation problems, subsoil water and also to the earthquake that affected the entire Greater Cairo area in October 1992. Ground Penetrating Radar (GPR) scan was accomplished against the walls of the opened floor (RADWAN Bench) to evaluate the hazard impact on the walls textures and integrity. The results showed an anomalous feature through the southern wall of RADWAN Bench. A mathematical model has been simulated to confirm the obtained anomaly and the model response exhibited a good matching with the outlined anomaly.

  19. Thermocouple homogeneity scanning

    NASA Astrophysics Data System (ADS)

    Webster, E.; White, D. R.

    2015-02-01

    The inhomogeneities within a thermocouple influence the measured temperature and contribute the largest component to uncertainty. Currently there is no accepted best practice for measuring the inhomogeneities or for forecasting their effects on real-world measurements. The aim of this paper is to provide guidance on the design and performance assessment of thermocouple inhomogeneity scanners by characterizing the qualitative performance of the various designs reported in the literature, and developing a quantitative measure of scanner resolution. Numerical simulations incorporating Fourier transforms and convolutions are used to gauge the levels of attenuation and distortion present in single- and double-gradient scanners. Single-gradient scanners are found to be far superior to double-gradient scanners, which are unsuitable for quantitative measurements due to their blindness to inhomogeneities at many spatial frequencies and severe attenuation of signals at other frequencies. It is recommended that the standard deviation of the temperature gradient within the scanner is used as a measure of the scanner resolution and spatial bandwidth. Recommendations for the design of scanners are presented, and include advice on the basic design of scanners, the media employed, operating temperature, scan rates, construction of survey probes, data processing, gradient symmetry, and the spatial resolution required for research and calibration applications.

  20. Scanning probe nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Dinelli, F.; Menozzi, C.; Baschieri, P.; Facci, P.; Pingue, P.

    2010-02-01

    The present paper reports on a novel lithographic approach at the nanoscale level, which is based on scanning probe microscopy (SPM) and nanoimprint lithography (NIL). The experimental set-up consists of an atomic force microscope (AFM) operated via software specifically developed for the purpose. In particular, this software allows one to apply a predefined external load for a given lapse of time while monitoring in real-time the relative distance between the tip and the sample as well as the normal and lateral force during the embossing process. Additionally, we have employed AFM tips sculptured by means of focused ion beam in order to create indenting tools of the desired shape. Anti-sticking layers can also be used to functionalize the tips if one needs to investigate the effects of different treatments on the indentation and de-molding processes. The lithographic capabilities of this set-up are demonstrated on a polystyrene NIL-patterned sample, where imprinted features have been obtained upon using different normal load values for increasing time intervals, and on a thermoplastic polymer film, where the imprint process has been monitored in real-time.

  1. LANL Robotic Vessel Scanning

    SciTech Connect

    Webber, Nels W.

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  2. Stochastic scanning multiphoton multifocal microscopy.

    PubMed

    Jureller, Justin E; Kim, Hee Y; Scherer, Norbert F

    2006-04-17

    Multiparticle tracking with scanning confocal and multiphoton fluorescence imaging is increasingly important for elucidating biological function, as in the transport of intracellular cargo-carrying vesicles. We demonstrate a simple rapid-sampling stochastic scanning multifocal multiphoton microscopy (SS-MMM) fluorescence imaging technique that enables multiparticle tracking without specialized hardware at rates 1,000 times greater than conventional single point raster scanning. Stochastic scanning of a diffractive optic generated 10x10 hexagonal array of foci with a white noise driven galvanometer yields a scan pattern that is random yet space-filling. SS-MMM creates a more uniformly sampled image with fewer spatio-temporal artifacts than obtained by conventional or multibeam raster scanning. SS-MMM is verified by simulation and experimentally demonstrated by tracking microsphere diffusion in solution. PMID:19516485

  3. Radioisotope scanning in osseous sarcoidosis

    SciTech Connect

    Rohatgi, P.K.

    1980-01-01

    Technetium-99m (/sup 99m/Tc)-labeled pyrophosphate or diphosphonate compounds and gallium-67 citrate (/sup 67/Ga) are two radionuclide scanning agents that are in widespread use in clinical practice. Technetium-99m pyrophosphate is used extensively for bone scanning to detect metastatic bone disease, benign bone tumors, osteomyelitis, benign hypertrophic osteoarthropathy, and Paget's disease. Only two reports describe abnormal /sup 99m/Tc/ pyrophosphate bone scans in four patients with osseous sarcoidosis. Gallium-67 scans are used primarily to localize neoplastic or inflammatory lesions anywhere in the body. In recent years /sup 67/Ga scans have also been used to detect the presence of both pulmonary and extrapulmonary sarcoidosis, but there are no reports describing abnormal uptake of gallium in patients with osseous sarcoidosis. This report describes experience with radioisotope scanning in two patients with osseous sarcoidosis.

  4. Hyperchromatic laser scanning cytometry

    NASA Astrophysics Data System (ADS)

    Tárnok, Attila; Mittag, Anja

    2007-02-01

    In the emerging fields of high-content and high-throughput single cell analysis for Systems Biology and Cytomics multi- and polychromatic analysis of biological specimens has become increasingly important. Combining different technologies and staining methods polychromatic analysis (i.e. using 8 or more fluorescent colors at a time) can be pushed forward to measure anything stainable in a cell, an approach termed hyperchromatic cytometry. For cytometric cell analysis microscope based Slide Based Cytometry (SBC) technologies are ideal as, unlike flow cytometry, they are non-consumptive, i.e. the analyzed sample is fixed on the slide. Based on the feature of relocation identical cells can be subsequently reanalyzed. In this manner data on the single cell level after manipulation steps can be collected. In this overview various components for hyperchromatic cytometry are demonstrated for a SBC instrument, the Laser Scanning Cytometer (Compucyte Corp., Cambridge, MA): 1) polychromatic cytometry, 2) iterative restaining (using the same fluorochrome for restaining and subsequent reanalysis), 3) differential photobleaching (differentiating fluorochromes by their different photostability), 4) photoactivation (activating fluorescent nanoparticles or photocaged dyes), and 5) photodestruction (destruction of FRET dyes). With the intelligent combination of several of these techniques hyperchromatic cytometry allows to quantify and analyze virtually all components of relevance on the identical cell. The combination of high-throughput and high-content SBC analysis with high-resolution confocal imaging allows clear verification of phenotypically distinct subpopulations of cells with structural information. The information gained per specimen is only limited by the number of available antibodies and by sterical hindrance.

  5. GyneScan

    PubMed Central

    Acharya, U. Rajendra; Sree, S. Vinitha; Kulshreshtha, Sanjeev; Molinari, Filippo; Koh, Joel En Wei; Saba, Luca; Suri, Jasjit S.

    2014-01-01

    Ovarian cancer is the fifth highest cause of cancer in women and the leading cause of death from gynecological cancers. Accurate diagnosis of ovarian cancer from acquired images is dependent on the expertise and experience of ultrasonographers or physicians, and is therefore, associated with inter observer variabilities. Computer Aided Diagnostic (CAD) techniques use a number of different data mining techniques to automatically predict the presence or absence of cancer, and therefore, are more reliable and accurate. A review of published literature in the field of CAD based ovarian cancer detection indicates that many studies use ultrasound images as the base for analysis. The key objective of this work is to propose an effective adjunct CAD technique called GyneScan for ovarian tumor detection in ultrasound images. In our proposed data mining framework, we extract several texture features based on first order statistics, Gray Level Co-occurrence Matrix and run length matrix. The significant features selected using t-test are then used to train and test several supervised learning based classifiers such as Probabilistic Neural Networks (PNN), Support Vector Machine (SVM), Decision Tree (DT), k-Nearest Neighbor (KNN), and Naïve Bayes (NB). We evaluated the developed framework using 1300 benign and 1300 malignant images. Using 11 significant features in KNN/PNN classifiers, we were able to achieve 100% classification accuracy, sensitivity, specificity, and positive predictive value in detecting ovarian tumor. Even though more validation using larger databases would better establish the robustness of our technique, the preliminary results are promising. This technique could be used as a reliable adjunct method to existing imaging modalities to provide a more confident second opinion on the presence/absence of ovarian tumor. PMID:24325128

  6. Continuous scanning mode for ptychography

    SciTech Connect

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross J.; Robinson, Ian K.

    2014-01-01

    Here, we outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. Furthermore, the impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  7. Continuous scanning mode for ptychography

    SciTech Connect

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross; Robinson, Ian K.

    2014-10-15

    We outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. The impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  8. Scanning Productivity in Interlibrary Loan

    ERIC Educational Resources Information Center

    Pedersen, Wayne A.; Runestad, Anders

    2009-01-01

    The authors report findings of a research study conducted at the Iowa State University Library. Data was gathered on the scanning of library materials by students working in the Interlibrary Loan (ILL) unit. The goals of the study were fourfold: (1) Develop measures of scanning productivity in ILL, (2) Determine if it is more productive to scan…

  9. Nuclear Medicine Scans for Cancer

    MedlinePlus

    ... are the possible complications? For the most part, nuclear scans are safe tests. The doses of radiation are very small, and the radionuclides have a ... else should I know about these tests? The radiation exposure from a nuclear scan comes from the radionuclides used – the scanner ...

  10. Scan converting video tape recorder

    NASA Technical Reports Server (NTRS)

    Holt, N. I. (Inventor)

    1971-01-01

    A video tape recorder is disclosed of sufficient bandwidth to record monochrome television signals or standard NTSC field sequential color at current European and American standards. The system includes scan conversion means for instantaneous playback at scanning standards different from those at which the recording is being made.

  11. An interchangeable scanning Hall probe/scanning SQUID microscope

    SciTech Connect

    Tang, Chiu-Chun; Lin, Hui-Ting; Wu, Sing-Lin; Chen, Tse-Jun; Wang, M. J.; Ling, D. C.; Chi, C. C.; Chen, Jeng-Chung

    2014-08-15

    We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (⩽4 μm), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10{sup −7} T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K.

  12. Large aperture scanning airborne lidar

    NASA Technical Reports Server (NTRS)

    Smith, J.; Bindschadler, R.; Boers, R.; Bufton, J. L.; Clem, D.; Garvin, J.; Melfi, S. H.

    1988-01-01

    A large aperture scanning airborne lidar facility is being developed to provide important new capabilities for airborne lidar sensor systems. The proposed scanning mechanism allows for a large aperture telescope (25 in. diameter) in front of an elliptical flat (25 x 36 in.) turning mirror positioned at a 45 degree angle with respect to the telescope optical axis. The lidar scanning capability will provide opportunities for acquiring new data sets for atmospheric, earth resources, and oceans communities. This completed facility will also make available the opportunity to acquire simulated EOS lidar data on a near global basis. The design and construction of this unique scanning mechanism presents exciting technological challenges of maintaining the turning mirror optical flatness during scanning while exposed to extreme temperatures, ambient pressures, aircraft vibrations, etc.

  13. Lidar arc scan uncertainty reduction through scanning geometry optimization

    NASA Astrophysics Data System (ADS)

    Wang, H.; Barthelmie, R. J.; Pryor, S. C.; Brown, G.

    2015-10-01

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.

  14. Circular Scan Streak Tube Development

    NASA Technical Reports Server (NTRS)

    Nevin, S.

    1980-01-01

    A streak tube having circular scan was designed, built and tested. Continuous circular scan, easily derived from out of phase sine waves applied to the conventional deflection plates, permits the timing of pulses traveling long baselines. At the tube's output a circular array of 720 elements is scanned to provide 30 to 40 picosecond resolution. Initial difficulties with electron bombarded silicon arrays were circumvented by using microchannel plates within the streak tube to provide the needed electronic amplification and digital sensitivity and coupling the 720 element arrays to the electron beam by means of a phosphor on a fiber optics. Two ceramic body tubes with S-20 photocathodes were tested and delivered.

  15. 3D light scanning macrography.

    PubMed

    Huber, D; Keller, M; Robert, D

    2001-08-01

    The technique of 3D light scanning macrography permits the non-invasive surface scanning of small specimens at magnifications up to 200x. Obviating both the problem of limited depth of field inherent to conventional close-up macrophotography and the metallic coating required by scanning electron microscopy, 3D light scanning macrography provides three-dimensional digital images of intact specimens without the loss of colour, texture and transparency information. This newly developed technique offers a versatile, portable and cost-efficient method for the non-invasive digital and photographic documentation of small objects. Computer controlled device operation and digital image acquisition facilitate fast and accurate quantitative morphometric investigations, and the technique offers a broad field of research and educational applications in biological, medical and materials sciences. PMID:11489078

  16. Scans as primitive parallel operations

    SciTech Connect

    Blelloch, G.E. . Dept. of Computer Science)

    1989-11-01

    In most parallel random access machine (PRAM) models, memory references are assumed to take unit time. In practice, and in theory, certain scan operations, also known as prefix computations, can execute in no more time than these parallel memory references. This paper outlines an extensive study of the effect of including, in the PRAM models, such scan operations as unit-time primitives. The study concludes that the primitives improve the asymptotic running time of many algorithms by an O(log n) factor greatly simplify the description of many algorithms, and are significantly easier to implement than memory references. The authors argue that the algorithm designer should feel free to use these operations as if they were as cheap as a memory reference. This paper describes five algorithms that clearly illustrate how the scan primitives can be used in algorithm design. These all run on an EREW PRAM with the addition of two scan primitives.

  17. Establishing an Environmental Scanning Process.

    ERIC Educational Resources Information Center

    Morrison, James L.

    1985-01-01

    A formal environmental scanning system designed to identify emerging issues, events, or trends threatening or bringing opportunity to an institution is discussed that uses a committee to systematically collect and analyze data from a variety of sources. (MSE)

  18. Transverse section radionuclide scanning system

    DOEpatents

    Kuhl, David E.; Edwards, Roy Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three-dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program.

  19. Eddy current scanning at Fermilab

    SciTech Connect

    Boffo, C.; Bauer, P.; Foley, M.; Brinkmann, A.; Ozelis, J.; /Jefferson Lab

    2005-07-01

    In the framework of SRF cavity development, Fermilab is creating the infrastructure needed for the characterization of the material used in the cavity fabrication. An important step in the characterization of ''as received'' niobium sheets is the eddy current scanning. Eddy current scanning is a non-destructive technique first adopted and further developed by DESY with the purpose of checking the cavity material for sub-surface defects and inclusions. Fermilab has received and further upgraded a commercial eddy current scanner previously used for the SNS project. The upgrading process included developing new filtering software. This scanner is now used daily to scan the niobium sheets for the Fermilab third harmonic and transverse deflecting cavities. This paper gives a status report on the scanning results obtained so far, including a discussion of the typology of signals being detected. We also report on the efforts to calibrate this scanner, a work conducted in collaboration with DESY.

  20. Scan registration using planar features

    NASA Astrophysics Data System (ADS)

    Previtali, M.; Barazzetti, L.; Brumana, R.; Scaioni, M.

    2014-06-01

    Point cloud acquisition by using laser scanners provides an efficient way for 3D as-built modelling of indoor/outdoor urban environments. In the case of large structures, multiple scans may be required to cover the entire scene and registration is needed to merge them together. In general, the identification of corresponding geometric features among a series of scans can be used to compute the 3D rigid-body transformation useful for the registration of each scan into the reference system of the final point cloud. Different automatic or semi-automatic methods have been developed to this purpose. Several solutions based on artificial targets are available, which however may not be suitable in any situations. Methods based on surface matching (like ICP and LS3D) can be applied if the scans to align have a proper geometry and surface texture. In the case of urban and architectural scenes that present the prevalence of a few basic geometric shapes ("Legoland" scenes) the availability of many planar features is exploited here for registration. The presented technique does not require artificial targets to be added to the scanned scene. In addition, unlike other surface-based techniques (like ICP) the planar feature-based registration technique is not limited to work in a pairwise manner but it can handle the simultaneous alignment of multiple scans. Finally, some applications are presented and discussed to show how this technique can achieve accuracy comparable to a consolidated registration method.

  1. Lidar arc scan uncertainty reduction through scanning geometry optimization

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-01

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.

  2. Deconvolution of sinusoidal rapid EPR scans.

    PubMed

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-02-01

    In rapid scan EPR the magnetic field is scanned through the signal in a time that is short relative to electron spin relaxation times. Previously it was shown that the slow-scan lineshape could be recovered from triangular rapid scans by Fourier deconvolution. In this paper a general Fourier deconvolution method is described and demonstrated to recover the slow-scan lineshape from sinusoidal rapid scans. Since an analytical expression for the Fourier transform of the driving function for a sinusoidal scan was not readily apparent, a numerical method was developed to do the deconvolution. The slow scan EPR lineshapes recovered from rapid triangular and sinusoidal scans are in excellent agreement for lithium phthalocyanine, a trityl radical, and the nitroxyl radical, tempone. The availability of a method to deconvolute sinusoidal rapid scans makes it possible to scan faster than is feasible for triangular scans because of hardware limitations on triangular scans. PMID:21163677

  3. Deconvolution of Sinusoidal Rapid EPR Scans

    PubMed Central

    Tseitlin, Mark; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    In rapid scan EPR the magnetic field is scanned through the signal in a time that is short relative to electron spin relaxation times. Previously it was shown that the slow scan lineshape could be recovered from triangular rapid scans by Fourier deconvolution. In this paper a general Fourier deconvolution method is described and demonstrated to recover the slow scan lineshape from sinusoidal rapid scans. Since an analytical expression for the Fourier transform of the driving function for a sinusoidal scan was not readily apparent, a numerical method was developed to do the deconvolution. The slow scan EPR lineshapes recovered from rapid triangular and sinusoidal scans are in excellent agreement for lithium phthalocyanine, a trityl radical, and the nitroxyl radical, tempone. The availability of a method to deconvolute sinusoidal rapid scans makes it possible to scan faster than is feasible for triangular scans because of hardware limitations on triangular scans. PMID:21163677

  4. Environmental Scanning and the Information Manager.

    ERIC Educational Resources Information Center

    Newsome, James; McInerney, Claire

    1990-01-01

    Discusses nine components of an environmental scanning model: selecting the scanning team; selecting resources to scan; choosing criteria for scanning; scanning the resources; identifying signals of new issues; selecting key events/issues; monitoring and analyzing events/issues; disseminating information; and deciding on appropriate organizational…

  5. Scanning Terahertz Heterodyne Imaging Systems

    NASA Technical Reports Server (NTRS)

    Siegel, Peter; Dengler, Robert

    2007-01-01

    Scanning terahertz heterodyne imaging systems are now at an early stage of development. In a basic scanning terahertz heterodyne imaging system, (see Figure 1) two far-infrared lasers generate beams denoted the local-oscillator (LO) and signal that differ in frequency by an amount, denoted the intermediate frequency (IF), chosen to suit the application. The LO beam is sent directly to a mixer as one of two inputs. The signal beam is focused to a spot on or in the specimen. After transmission through or reflection from the specimen, the beams are focused to a spot on a terahertz mixer, which extracts the IF outputs. The specimen is mounted on a translation stage, by means of which the focal spot is scanned across the specimen to build up an image.

  6. What Is a Nuclear Heart Scan?

    MedlinePlus

    ... from the NHLBI on Twitter. What Is a Nuclear Heart Scan? A nuclear heart scan is a test that provides important ... use it to create pictures of your heart. Nuclear heart scans are used for three main purposes: ...

  7. Conically scanned holographic lidar telescope

    NASA Technical Reports Server (NTRS)

    Schwemmer, Geary (Inventor)

    1993-01-01

    An optical scanning device utilizing a source of optical energy such as laser light backscattered from the earth's atmosphere or transmitted outward as in a lidar, a rotating holographic optical element having an axis of rotation perpendicular to the plane of its substrate, and having a stationary focus which may or may not be located on its axis of rotation, with the holographic optical element diffracting the source of optical energy at an angle to its rotation axis enabling a conical scanning area and a motor for supporting and rotating the rotating holographic optical element, is described.

  8. Scanning color optical tomography (SCOT).

    PubMed

    Hosseini, Poorya; Sung, Yongjin; Choi, Youngwoon; Lue, Niyom; Yaqoob, Zahid; So, Peter

    2015-07-27

    We have developed an interferometric optical microscope that provides three-dimensional refractive index map of a specimen by scanning the color of three illumination beams. Our design of the interferometer allows for simultaneous measurement of the scattered fields (both amplitude and phase) of such a complex input beam. By obviating the need for mechanical scanning of the illumination beam or detection objective lens; the proposed method can increase the speed of the optical tomography by orders of magnitude. We demonstrate our method using polystyrene beads of known refractive index value and live cells. PMID:26367632

  9. Scanning color optical tomography (SCOT)

    PubMed Central

    Hosseini, Poorya; Sung, Yongjin; Choi, Youngwoon; Lue, Niyom; Yaqoob, Zahid; So, Peter

    2015-01-01

    We have developed an interferometric optical microscope that provides three-dimensional refractive index map of a specimen by scanning the color of three illumination beams. Our design of the interferometer allows for simultaneous measurement of the scattered fields (both amplitude and phase) of such a complex input beam. By obviating the need for mechanical scanning of the illumination beam or detection objective lens; the proposed method can increase the speed of the optical tomography by orders of magnitude. We demonstrate our method using polystyrene beads of known refractive index value and live cells. PMID:26367632

  10. Lidar arc scan uncertainty reduction through scanning geometry optimization

    DOE PAGESBeta

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annualmore » energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  11. Lidar arc scan uncertainty reduction through scanning geometry optimization

    DOE PAGESBeta

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annualmore » energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30% of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. As a result, large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  12. Environmental Scanning, Vancouver Community College.

    ERIC Educational Resources Information Center

    Yao, Min

    This 1994 environmental scanning report from Vancouver Community College (VCC) reviews the expected effects of the separation of VCC into a new Vancouver Community College and Langara College (LC). The report examines the projected service area student-intake capacity; student characteristics; population growth trends; other postsecondary…

  13. Developing an Environmental Scanning System.

    ERIC Educational Resources Information Center

    Morrison, James L.

    A step-by-step approach is provided for developing an environmental scanning system for colleges and universities to assist them in planning for the future. The objectives of such a system are to detect social, scientific, economic, technical, and political interactions important to the organization; define potential threats and opportunities from…

  14. Line-scanning laser ophthalmoscope

    NASA Astrophysics Data System (ADS)

    Hammer, Daniel X.; Ferguson, R. Daniel; Ustun, Teoman E.; Bigelow, Chad E.; Iftimia, Nicusor V.; Webb, Robert H.

    2006-07-01

    Scanning laser ophthalmoscopy (SLO) is a powerful imaging tool with specialized applications limited to research and ophthalmology clinics due in part to instrument size, cost, and complexity. Conversely, low-cost retinal imaging devices have limited capabilities in screening, detection, and diagnosis of diseases. To fill the niche between these two, a hand-held, nonmydriatic line-scanning laser ophthalmoscope (LSLO) is designed, constructed, and tested on normal human subjects. The LSLO has only one moving part and uses a novel optical approach to produce wide-field confocal fundus images. Imaging modes include multiwavelength illumination and live stereoscopic imaging with a split aperture. Image processing and display functions are controlled with two stacked prototype compact printed circuit boards. With near shot-noise limited performance, the digital LSLO camera requires low illumination power (<500 µW) at near-infrared wavelengths. The line-scanning principle of operation is examined in comparison to SLO and other imaging modes. The line-scanning approach produces high-contrast confocal images with nearly the same performance as a flying-spot SLO. The LSLO may significantly enhance SLO utility for routine use by ophthalmologists, optometrists, general practitioners, and also emergency medical personnel and technicians in the field for retinal disease detection and other diverse applications.

  15. Scanning tunneling microscope nanoetching method

    DOEpatents

    Li, Yun-Zhong; Reifenberger, Ronald G.; Andres, Ronald P.

    1990-01-01

    A method is described for forming uniform nanometer sized depressions on the surface of a conducting substrate. A tunneling tip is used to apply tunneling current density sufficient to vaporize a localized area of the substrate surface. The resulting depressions or craters in the substrate surface can be formed in information encoding patterns readable with a scanning tunneling microscope.

  16. Thermal radiation scanning tunnelling microscopy

    NASA Astrophysics Data System (ADS)

    de Wilde, Yannick; Formanek, Florian; Carminati, Rémi; Gralak, Boris; Lemoine, Paul-Arthur; Joulain, Karl; Mulet, Jean-Philippe; Chen, Yong; Greffet, Jean-Jacques

    2006-12-01

    In standard near-field scanning optical microscopy (NSOM), a subwavelength probe acts as an optical `stethoscope' to map the near field produced at the sample surface by external illumination. This technique has been applied using visible, infrared, terahertz and gigahertz radiation to illuminate the sample, providing a resolution well beyond the diffraction limit. NSOM is well suited to study surface waves such as surface plasmons or surface-phonon polaritons. Using an aperture NSOM with visible laser illumination, a near-field interference pattern around a corral structure has been observed, whose features were similar to the scanning tunnelling microscope image of the electronic waves in a quantum corral. Here we describe an infrared NSOM that operates without any external illumination: it is a near-field analogue of a night-vision camera, making use of the thermal infrared evanescent fields emitted by the surface, and behaves as an optical scanning tunnelling microscope. We therefore term this instrument a `thermal radiation scanning tunnelling microscope' (TRSTM). We show the first TRSTM images of thermally excited surface plasmons, and demonstrate spatial coherence effects in near-field thermal emission.

  17. Phase multiplying electronic scanning array

    NASA Technical Reports Server (NTRS)

    Seaton, A. F.

    1969-01-01

    Scanning array was designed with properties of low RF loss and phase control. The array consists of a series of special waveguides, hybrids made up of two variable reactance branch arms for input signals, an edge slot for the difference port, and a sum arm for the unradiated signal.

  18. Infrared Scanning For Electrical Maintenance

    NASA Astrophysics Data System (ADS)

    Eisenbath, Steven E.

    1983-03-01

    Given the technological age that we have now entered, the purpose of this paper is to relate how infrared scanning can be used for an electrical preventative maintenance program. An infrared scanner is able to produce an image because objects give off infrared radiation in relationship to their temperature. Most electrical problems will show up as an increase in temperature, thereby making the infrared scanner a useful preventative maintenance tool. Because of the sensitivity of most of the scanners, .1 to .2 of a degree, virtually all electrical problems can be pinpointed long before they become a costly failure. One of the early uses of infrared scanning was to check the power company's electrical distribution system. Most of this was performed via aircraft or truck mounted scanning devices which necessitated its semi-permanent mounting. With the advent of small hand held infrared imagers, along with more portability of the larger systems, infrared scanning has gained more popularity in checking electrical distribution systems. But the distribution systems are now a scaled down model, mainly the in-plant electrical systems. By in-plant, I mean any distribution of electricity; once it leaves the power company's grid. This can be in a hospital, retail outlet, warehouse or manufacturing facility.

  19. Scanned optical fiber confocal microscope

    NASA Astrophysics Data System (ADS)

    Dickensheets, David L.; Kino, Gordon S.

    1994-04-01

    The size and weight of conventional optical microscopes often makes them inconvenient for use on the human body or for in-situ examination during materials processing. We describe a new fiber-optic scanning confocal optical microscope which could have a total outside diameter as small as 1 mm, and should lend itself to applications in endoscopy or to optical in vivo histology. The first experimental device utilizes a single-mode optical fiber for illumination and detection. The scanning element is a mechanically resonant fused silica cantilever 1.5 cm long and 0.8 mm across, with a micromachined two-phase zone plate objective mounted at one end. The cantilever is electrostatically scanned near resonance in two dimensions, generating a Lissajous pattern which is scan converted to conventional video for real time display or digitization. The objective lens has N.A. equals 0.25 at (lambda) equals 0.6328 micrometers , with a measured spot size of 1.8 micrometers FWHM.

  20. Electronically-Scanned Pressure Sensors

    NASA Technical Reports Server (NTRS)

    Coe, C. F.; Parra, G. T.; Kauffman, R. C.

    1984-01-01

    Sensors not pneumatically switched. Electronic pressure-transducer scanning system constructed in modular form. Pressure transducer modules and analog to digital converter module small enough to fit within cavities of average-sized wind-tunnel models. All switching done electronically. Temperature controlled environment maintained within sensor modules so accuracy maintained while ambient temperature varies.

  1. Pulmonary ventilation/perfusion scan

    MedlinePlus

    ... Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. Related MedlinePlus Health Topics COPD Lung Diseases Nuclear Scans Pulmonary Embolism Browse the Encyclopedia A.D. ...

  2. Improvement of CAT scanned images

    NASA Technical Reports Server (NTRS)

    Roberts, E., Jr.

    1980-01-01

    Digital enhancement procedure improves definition of images. Tomogram is generated from large number of X-ray beams. Beams are collimated and small in diameter. Scanning device passes beams sequentially through human subject at many different angles. Battery of transducers opposite subject senses attenuated signals. Signals are transmitted to computer where they are used in construction of image on transverse plane through body.

  3. A CAT scan for cells

    SciTech Connect

    2009-01-01

    Recently, a team of scientists from Berkeley Lab, Stanford University, and the University of California, San Francisco used Berkeley Lab's National Center for X-ray Tomography to capture the changes that occur when Candida albicans is exposed to a new and promising antifungal therapy. http://newscenter.lbl.gov/feature-stories/2009/12/10/cat-scan-cells/

  4. Conically Scanned Holographic LIDAR Telescope

    NASA Technical Reports Server (NTRS)

    Schwemmer, Geary

    1993-01-01

    Holographic LIDAR telescope includes holographic disk, rotation of which sweeps collimated, monochromatic beam of light from laser through conical scan. Holographic disk diffracts light scattered back from target volume or area to focal point located at stationary photomultiplier detector. Two conical baffles prevent stray light from reaching detector.

  5. Ultrasonic scanning of multilayer ceramic chip capacitors

    NASA Technical Reports Server (NTRS)

    Bradley, F. N.

    1981-01-01

    Ultrasonic scanning is compared to neutron radiography and scanning laser acoustic microscopy (SLAM). Data show that SLAM and ultrasonic scanning evaluations are in good agreement. There is poor agreement between N-ray and both ultrasonic techniques because N-ray is insensitive to all but the grossest delaminations. Statistical analysis show a good correlation between ultrasonic scanning and destructive physical analysis.

  6. Patient preparation and scanning techniques.

    PubMed

    Taylor, Carolyn M; Blum, Andrew; Abbara, Suhny

    2010-07-01

    Cardiac computed tomographic angiography (CCTA) is a unique diagnostic modality that can provide a comprehensive assessment of cardiac anatomy. Rapid advances in scanner and software technology have resulted in the ability to noninvasively image the coronary arteries. However, careful patient preparation and scanning technique is required to ensure optimal image quality while minimizing radiation dose delivered. Important components of patient preparation include knowledge of the indications and contraindications for CCTA, patient screening, patient premedication, patient positioning, prescan instruction, and electrocardiograph lead placement. Scanning technique should be determined on a patient by patient basis and tailored according to age and radiation risk, body mass index and chest circumference, heart rate and variability, presence of stents, and coronary calcification. PMID:20705165

  7. Children, CT Scan and Radiation

    PubMed Central

    Bajoghli, Morteza; Bajoghli, Farshad; Tayari, Nazila; Rouzbahani, Reza

    2010-01-01

    Children are more sensitive to radiation than adults. Computerized tomography (CT) consists of 25 % of all medical imaging. It was estimated that more than 2% of all carcinomas in the USA are due to CT scans. There is an ongoing focus on the reduction of CT scan radiation dose. Awareness about risk-benefits of CT has increased. Reduction of radiological exam is an important issue because the accumulation effects of radiation can be hazardous. In addition, proper protocol should be followed for diagnostic procedures of ionization radiation and computerized tomography. Effective radiation dose should range from 0.8 to 10.5 millisievert. The same protocol should be followed in different hospitals as well. Basic principles of radiation protection should be monitored. As much as possible, both technician and radiologist must be present during computerized tomography for children, and MRI and ultrasound should be replaced if possible. PMID:21566776

  8. Scanning phononic lattices with ultrasound

    SciTech Connect

    Vines, R.E.; Wolfe, J.P.; Every, A.V.

    1999-11-01

    A method for probing the elastic properties of newly developed periodic structures using acoustic waves is introduced. Highly anisotropic transmission of surface acoustic waves is observed by continuously scanning the wave vector angle. Preliminary models of wave propagation through multilayers and two-dimensional lattices explain some of the experimental features, while other features can be attributed to the resonant excitation of interface waves. {copyright} {ital 1999} {ital The American Physical Society}

  9. Differential scanning calorimetry of coal

    NASA Technical Reports Server (NTRS)

    Gold, P. I.

    1978-01-01

    Differential scanning calorimetry studies performed during the first year of this project demonstrated the occurrence of exothermic reactions associated with the production of volatile matter in or near the plastic region. The temperature and magnitude of the exothermic peak were observed to be strongly affected by the heating rate, sample mass and, to a lesser extent, by sample particle size. Thermal properties also were found to be influenced by oxidation of the coal sample due to weathering effects.

  10. Cloud Top Scanning radiometer (CTS)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A scanning radiometer to be used for measuring cloud radiances in each of three spectral regions is described. Significant features incorporated in the Cloud Top Scanner design are: (1) flexibility and growth potential through use of easily replaceable modular detectors and filters; (2) full aperture, multilevel inflight calibration; (3) inherent channel registration through employment of a single shared field stop; and (4) radiometric sensitivity margin in a compact optical design through use of Honeywell developed (Hg,Cd)Te detectors and preamplifiers.

  11. Influence of scanning variables on ultrasonic response

    SciTech Connect

    Cook, K.V.; Latimer, P.J.; McClung, R.W.

    1982-12-01

    The effects of scanning variables such as scanning speed, contact pressure, and couplant viscosity and their impact on ultrasonic amplitude response were considered. In addition, the surface adherence with repeated scanning was investigated for the commonly used couplants. We employed the results of this investigation to consider the relative merits of the various couplants for use in mechanized scanning. Of the couplants tested, water, glycerin, or a mixture of the two gave the best results for automated scanning applications.

  12. Noncontact scanning electrical impedance imaging.

    PubMed

    Liu, Hongze; Hawkins, Aaron; Schultz, Stephen; Oliphant, Travis E

    2004-01-01

    We are interested in applying electrical impedance imaging to a single cell because it has potential to reveal both cell anatomy and cell function. Unfortunately, classic impedance imaging techniques are not applicable to this small scale measurement due to their low resolution. In this paper, a different method of impedance imaging is developed based on a noncontact scanning system. In this system, the imaging sample is immersed in an aqueous solution allowing for the use of various probe designs. Among those designs, we discuss a novel shield-probe design that has the advantage of better signal-to-noise ratio with higher resolution compared to other probes. Images showing the magnitude of current for each scanned point were obtained using this configuration. A low-frequency linear physical model helps to relate the current to the conductivity at each point. Line-scan data of high impedance contrast structures can be shown to be a good fit to this model. The first two-dimensional impedance image of biological tissues generated by this technique is shown with resolution on the order of 100 mum. The image reveals details not present in the optical image. PMID:17271930

  13. Environmental scanning for Social Services.

    PubMed

    Russell, S; Prince, M J

    1992-10-01

    This article describes the development of a process of systematic regional environmental scanning as part of strategic planning in the Ministry of Social Services (MSS) in British Columbia, over the 1987-1990 period. Social Services, a large regionalized social service organization, adopted a formal strategic planning process in early 1988. Ministry services are delivered in ten regions with widely varying characteristics. To ensure that this diversity is reflected in the planning process, it is essential that regional environmental information receive consideration. A simple format was developed and regional directors asked to consult with their staff and to scan their regions for issues that may impact the ministry over the medium term. The information obtained was presented by regional directors at a Senior Management Committee meeting and included in the ministry's annual Business Plan, a document which informs staff, contractors, stakeholders, and the community at large of the ministry's values, objectives, and operational goals. The inclusion of regional analyses adds useful information to the Plan. A second output of the planning process is the ministry budget. The systematic regional scans were found to be extremely useful to regional staff, other directors, and to the ministry executives while setting priorities. PMID:10122390

  14. Mechanically scanned deployable antenna study

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The conceptual design of a Mechanically Scanned Deployable Antenna which is launched by the STS (Space Shuttle) to provide radiometric brightness temperature maps of the Earth and oceans at selected frequency bands in the frequency range of 1.4 GHz to 11 GHz is presented. Unlike previous scanning radiometric systems, multiple radiometers for each frequency are required in order to fill in the resolution cells across the swath created by the 15 meter diameter spin stabilized system. This multiple beam radiometric system is sometimes designated as a ""whiskbroom'' system in that it combines the techniques of the scanning and ""pushbroom'' type systems. The definition of the feed system including possible feed elements and location, determination of the fundamental reflector feed offset geometry including offset angles and f/D ratio, preliminary estimates of the beam efficiency of the feed reflector system, a summary of reflector mesh losses at the proposed radiometric frequency bands, an overall conceptual configuration design and preliminary structural and thermal analyses are included.

  15. Electronic scanning-slit fluorography.

    PubMed

    Plenkovich, D

    1989-01-01

    Scattered radiation degrades contrast and signal-to-noise ratio of an x-ray image. If an image intensifier is used as the image receptor, scattering of light photons and electrons within the image intensifier, optical system, and video camera produces veiling glare. anti-scatter grids, air gaps, and paired scanning slits have been used for rejection of scattered radiation. However, none of these methods is effective against veiling glare, because veiling glare is generated after the radiation has passed through any of these anti-scatter devices. In chapter 1 is introduced an innovative approach for highly efficient rejection of both scattered radiation and veiling glare in digital fluorography. This method has been named electronic collimation, and the x-ray imaging technique based upon it is called electronic scanning-slit fluorography. It involves replacing paired fore and aft slits for scatter rejection with only one beam-defining tantalum fore aperture. As this aperture scans across the portion of the patient to be imaged, pulsed x-ray exposures produce images which are digitized and stored in the computer memory. Since the video signal within the projection of the aperture on the image intensifier is much more intense than behind the tantalum, one can discriminate electronically between these two signals and thus eliminate the unwanted x-ray scatter and veiling glare. Such electronic collimation does not require synchronization between the slit scanning and detector readout, which makes it much simpler than alternative methods and potentially adaptable to any digital fluorography system. Theoretical considerations relevant for the construction and evaluation of a prototype unit for electronic scanning slit fluorography are presented in Chapter 2. This chapter consists of four sections. In the first section 'Principles of image detection' the concepts of quantum efficiency and detective quantum efficiency (DQE) are introduced as the most meaningful way to

  16. Scanning mirror for infrared sensors

    NASA Technical Reports Server (NTRS)

    Anderson, R. H.; Bernstein, S. B.

    1972-01-01

    A high resolution, long life angle-encoded scanning mirror, built for application in an infrared attitude sensor, is described. The mirror uses a Moire' fringe type optical encoder and unique torsion bar suspension together with a magnetic drive to meet stringent operational and environmental requirements at a minimum weight and with minimum power consumption. Details of the specifications, design, and construction are presented with an analysis of the mirror suspension that allows accurate prediction of performance. The emphasis is on mechanical design considerations, and brief discussions are included on the encoder and magnetic drive to provide a complete view of the mirror system and its capabilities.

  17. Statistical dependency in visual scanning

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Stark, Lawrence

    1986-01-01

    A method to identify statistical dependencies in the positions of eye fixations is developed and applied to eye movement data from subjects who viewed dynamic displays of air traffic and judged future relative position of aircraft. Analysis of approximately 23,000 fixations on points of interest on the display identified statistical dependencies in scanning that were independent of the physical placement of the points of interest. Identification of these dependencies is inconsistent with random-sampling-based theories used to model visual search and information seeking.

  18. Aperture scanning Fourier ptychographic microscopy

    PubMed Central

    Ou, Xiaoze; Chung, Jaebum; Horstmeyer, Roarke; Yang, Changhuei

    2016-01-01

    Fourier ptychographic microscopy (FPM) is implemented through aperture scanning by an LCOS spatial light modulator at the back focal plane of the objective lens. This FPM configuration enables the capturing of the complex scattered field for a 3D sample both in the transmissive mode and the reflective mode. We further show that by combining with the compressive sensing theory, the reconstructed 2D complex scattered field can be used to recover the 3D sample scattering density. This implementation expands the scope of application for FPM and can be beneficial for areas such as tissue imaging and wafer inspection. PMID:27570705

  19. Scanning Miniature Microscopes without Lenses

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2009-01-01

    The figure schematically depicts some alternative designs of proposed compact, lightweight optoelectronic microscopes that would contain no lenses and would generate magnified video images of specimens. Microscopes of this type were described previously in Miniature Microscope Without Lenses (NPO - 20218), NASA Tech Briefs, Vol. 22, No. 8 (August 1998), page 43 and Reflective Variants of Miniature Microscope Without Lenses (NPO 20610), NASA Tech Briefs, Vol. 26, No. 9 (September 1999), page 6a. To recapitulate: In the design and construction of a microscope of this type, the focusing optics of a conventional microscope are replaced by a combination of a microchannel filter and a charge-coupled-device (CCD) image detector. Elimination of focusing optics reduces the size and weight of the instrument and eliminates the need for the time-consuming focusing operation. The microscopes described in the cited prior articles contained two-dimensional CCDs registered with two-dimensional arrays of microchannels and, as such, were designed to produce full two-dimensional images, without need for scanning. The microscopes of the present proposal would contain one-dimensional (line image) CCDs registered with linear arrays of microchannels. In the operation of such a microscope, one would scan a specimen along a line perpendicular to the array axis (in other words, one would scan in pushbroom fashion). One could then synthesize a full two-dimensional image of the specimen from the line-image data acquired at one-pixel increments of position along the scan. In one of the proposed microscopes, a beam of unpolarized light for illuminating the specimen would enter from the side. This light would be reflected down onto the specimen by a nonpolarizing beam splitter attached to the microchannels at their lower ends. A portion of the light incident on the specimen would be reflected upward, through the beam splitter and along the microchannels, to form an image on the CCD. If the

  20. High Resolution Scanning Reflectarray Antenna

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R. (Inventor); Miranda, Felix A. (Inventor)

    2000-01-01

    The present invention provides a High Resolution Scanning Reflectarray Antenna (HRSRA) for the purpose of tracking ground terminals and space craft communication applications. The present invention provides an alternative to using gimbaled parabolic dish antennas and direct radiating phased arrays. When compared to a gimbaled parabolic dish, the HRSRA offers the advantages of vibration free steering without incurring appreciable cost or prime power penalties. In addition, it offers full beam steering at a fraction of the cost of direct radiating arrays and is more efficient.

  1. Schistosomiasis collection at NHM (SCAN)

    PubMed Central

    2012-01-01

    Background The Natural History Museum (NHM) is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN) as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL). This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL’s existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: · Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, · Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, · Provision of access to snail and schistosome collections for approved research activities. PMID:22943137

  2. Using Environmental Scans in Educational Needs Assessment.

    ERIC Educational Resources Information Center

    Hatch, Terry F.; Pearson, Thomas G.

    1998-01-01

    Presents advantages and disadvantages of environmental scanning for assessing the context of professional continuing education. Provides a checklist for evaluating the quality and usefulness of information sources. Addresses the ethics of scanning. (SK)

  3. CERES Spatial Extent and Scan Modes

    Atmospheric Science Data Center

    2013-04-03

    ... CERES Examples: Spatial Extent and Scan Modes The first three images shown below show the areal coverage for ... the areal coverage and characteristics of particular CERES scan modes performed by the CERES instruments. The Cross-Track mode, a Fixed ...

  4. Electronically-Scanned Fourier-Transform Spectrometer

    NASA Technical Reports Server (NTRS)

    Breckinridge, J. B.; Ocallaghan, F. G.

    1984-01-01

    Instrument efficient, lightweight, and stable. Fourier-transform spectrometer configuration uses electronic, instead of mechanical, scanning. Configuration insensitive to vibration-induced sampling errors introduced into mechanically scanned systems.

  5. Three-dimensional scanning confocal laser microscope

    DOEpatents

    Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind

    1999-01-01

    A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

  6. Rapid-Scan EPR of Immobilized Nitroxides

    PubMed Central

    Yu, Zhelin; Quine, Richard W.; Rinard, George A.; Tseitlin, Mark; Elajaili, Hanan; Kathirvelu, Velavan; Clouston, Laura J.; Boratyński, Przemysław J.; Rajca, Andrzej; Stein, Richard; Mchaourab, Hassane; Eaton, Sandra S.; Eaton, Gareth R.

    2014-01-01

    X-band electron paramagnetic resonance spectra of immobilized nitroxides were obtained by rapid scan at 293 K. Scan widths were 155 G with 13.4 kHz scan frequency for 14N-perdeuterated tempone and for T4 lysozyme doubly spin labeled with an iodoacetamide spirocyclohexyl nitroxide and 100 G with 20.9 kHz scan frequency for 15N-perdeuterated tempone. These wide scans were made possible by modifications to our rapid-scan driver, scan coils made of Litz wire, and the placement of highly conducting aluminum plates on the poles of a Bruker 10" magnet to reduce resistive losses in the magnet pole faces. For the same data acquisition time, the signal-to-noise for the rapid-scan absorption spectra was about an order of magnitude higher than for continuous wave first-derivative spectra recorded with modulation amplitudes that do not broaden the lineshapes. PMID:25240151

  7. Rapid-scan EPR of immobilized nitroxides.

    PubMed

    Yu, Zhelin; Quine, Richard W; Rinard, George A; Tseitlin, Mark; Elajaili, Hanan; Kathirvelu, Velavan; Clouston, Laura J; Boratyński, Przemysław J; Rajca, Andrzej; Stein, Richard; Mchaourab, Hassane; Eaton, Sandra S; Eaton, Gareth R

    2014-10-01

    X-band electron paramagnetic resonance spectra of immobilized nitroxides were obtained by rapid scan at 293 K. Scan widths were 155 G with 13.4 kHz scan frequency for (14)N-perdeuterated tempone and for T4 lysozyme doubly spin labeled with an iodoacetamide spirocyclohexyl nitroxide and 100 G with 20.9 kHz scan frequency for (15)N-perdeuterated tempone. These wide scans were made possible by modifications to our rapid-scan driver, scan coils made of Litz wire, and the placement of highly conducting aluminum plates on the poles of a Bruker 10″ magnet to reduce resistive losses in the magnet pole faces. For the same data acquisition time, the signal-to-noise for the rapid-scan absorption spectra was about an order of magnitude higher than for continuous wave first-derivative spectra recorded with modulation amplitudes that do not broaden the lineshapes. PMID:25240151

  8. Issue Scanning: Finding the Future...Maybe.

    ERIC Educational Resources Information Center

    Plog, Michael; Sweeney, Jim; Weiss, Barry

    Issue Scanning, sometimes called Environmental Scanning, is used in many business, government, educational, and nonprofit organizations. The technique is supposed to monitor the "pulse" of the external environment. The scanning process should lessen the randomness of the information used in decision making, and it should alert managers to trends…

  9. Suspension system for gimbal supported scanning payloads

    NASA Technical Reports Server (NTRS)

    Polites, Michael E. (Inventor)

    1995-01-01

    Gimballed scanning devices or instruments are the subject of this invention. Scanning is an important aspect of space science. To achieve a scan pattern some means must be provided which impart to the payload an oscillatory motion. Various forms of machines have been employed for controllably conferring on scanning instruments predetermined scan patterns. They include control moment gyroscopes, reaction wheels, torque motors, reaction control systems, and the like. But rotating unbalanced mass (RUM) devices are a new and efficient way to generate scans in gimballed payloads. RUM devices are superior to previous scanning apparatus, but they require power consuming and frequently complex auxiliary control systems to position and reposition the particular scan pattern relative to a target or a number of targets. Herein the control system is simplified. The most frequently employed method for achieving the various scan patterns is to gimbal the scanning device. Gimbals are suspended in such a way that they can be activated to generate the scan pattern. The suspension means described is for payloads supported in gimbals wherein the payload rotation is restricted by a flex pivot so that the payload oscillates, thereby moving in a scan pattern.

  10. South Carolina Course Alignment Project: Environmental Scan

    ERIC Educational Resources Information Center

    Educational Policy Improvement Center (NJ1), 2007

    2007-01-01

    An "environmental scan" is designed to identify key issues of policy and practice in an area of interest so that action can be taken. By definition, an environmental scan focuses upon areas of concern. However, the results of an environmental scan are not designed to be either an indictment or endorsement of the current way of doing business since…

  11. Laser scanning by rotating polarization gratings.

    PubMed

    Zhou, Yuan; Fan, Dapeng; Fan, Shixun; Chen, Ying; Liu, Guangcan

    2016-07-01

    Laser beam scanning can be realized using two independently rotating, inline polarization gratings, termed Risley gratings, in a fashion similar to Risley prisms. The analytical formulas of pointing position as well as their inverse solutions are described. On this basis, the beam scanning is investigated and the performance of scanning imaging is evaluated. It is shown that the scanning function in 1D scanning evolves from a sinusoidal to triangular scan and the duty cycle increases rapidly as the ratio of grating period to wavelength is reduced toward 2. The scan pattern in 2D scanning is determined by the ratio k of the gratings' rotatory frequency. In imaging applications, when k tends toward 1 or -1, the scan pattern becomes dense and is inclined to be spiral or rose-like, respectively, which is desirable for the purpose of enhancing spatial resolution. There is a direct trade-off between spatial resolution and frame rate. The spiral and rose scanning enable multiresolution imaging, providing a preview of the scanned area in a fraction of the overall scan time, which is extremely useful for fast, real-time imaging applications. PMID:27409203

  12. Optical scanning tests of complex CMOS microcircuits

    NASA Technical Reports Server (NTRS)

    Levy, M. E.; Erickson, J. J.

    1977-01-01

    The new test method was based on the use of a raster-scanned optical stimulus in combination with special electrical test procedures. The raster-scanned optical stimulus was provided by an optical spot scanner, an instrument that combines a scanning optical microscope with electronic instrumentation to process and display the electric photoresponse signal induced in a device that is being tested.

  13. Improving cranial ultrasound scanning strategy in neonates

    PubMed Central

    Bray, Lisa

    2016-01-01

    Cranial ultrasound scans are undertaken in this tertiary neonatal intensive care unit by the doctors within the department. A quality improvement project was undertaken by means of two PDSA cycles to determine adherence to neonatal cranial ultrasound scanning schedule, assess the quality of scan reporting, and formulate a comprehensive guideline outlining best practice. The baseline measurements assessed 93 scans of preterm infants and 9 of term infants. The results of this prompted intradepartmental education (PDSA cycle 1) then creation and implementation of a documentation template, a local guideline, and education via presentations, posters, and email (PDSA cycle 2). These encompassed 77 preterm and 5 term scans. In our baseline measurements, 52% of preterm infant scans and 44% of term infant scans were performed to schedule. Of premature baby scan reports, 75% had the time documented and 92% the name of the scanning doctor. After implementing changes PDSA cycle 2 data showed that 74% of preterm infant scans and all term infant scans were performed according to schedule, with 100% having the doctor's name and time of scan documented. We successfully introduced a guideline and documentation template, improving performance to schedule and documentation in most areas. It remains an ongoing challenge to adhere to basic standards of documentation; a template can assist in achieving this. Rotating trainees may offer insight into areas that could benefit from quality improvement. This enthusiasm can be successfully harnessed to implement changes to improve quality of patient care. PMID:27096095

  14. Improving cranial ultrasound scanning strategy in neonates.

    PubMed

    Bray, Lisa

    2016-01-01

    Cranial ultrasound scans are undertaken in this tertiary neonatal intensive care unit by the doctors within the department. A quality improvement project was undertaken by means of two PDSA cycles to determine adherence to neonatal cranial ultrasound scanning schedule, assess the quality of scan reporting, and formulate a comprehensive guideline outlining best practice. The baseline measurements assessed 93 scans of preterm infants and 9 of term infants. The results of this prompted intradepartmental education (PDSA cycle 1) then creation and implementation of a documentation template, a local guideline, and education via presentations, posters, and email (PDSA cycle 2). These encompassed 77 preterm and 5 term scans. In our baseline measurements, 52% of preterm infant scans and 44% of term infant scans were performed to schedule. Of premature baby scan reports, 75% had the time documented and 92% the name of the scanning doctor. After implementing changes PDSA cycle 2 data showed that 74% of preterm infant scans and all term infant scans were performed according to schedule, with 100% having the doctor's name and time of scan documented. We successfully introduced a guideline and documentation template, improving performance to schedule and documentation in most areas. It remains an ongoing challenge to adhere to basic standards of documentation; a template can assist in achieving this. Rotating trainees may offer insight into areas that could benefit from quality improvement. This enthusiasm can be successfully harnessed to implement changes to improve quality of patient care. PMID:27096095

  15. UAVSAR Active Electronically Scanned Array

    NASA Technical Reports Server (NTRS)

    Sadowy, Gregory, A.; Chamberlain, Neil F.; Zawadzki, Mark S.; Brown, Kyle M.; Fisher, Charles D.; Figueroa, Harry S.; Hamilton, Gary A.; Jones, Cathleen E.; Vorperian, Vatche; Grando, Maurio B.

    2011-01-01

    The Uninhabited Airborne Vehicle Synthetic Aperture Radar (UAVSAR) is a pod-based, L-band (1.26 GHz), repeatpass, interferometric, synthetic aperture radar (InSAR) used for Earth science applications. Repeat-pass interferometric radar measurements from an airborne platform require an antenna that can be steered to maintain the same angle with respect to the flight track over a wide range of aircraft yaw angles. In order to be able to collect repeat-pass InSAR data over a wide range of wind conditions, UAVSAR employs an active electronically scanned array (AESA). During data collection, the UAVSAR flight software continuously reads the aircraft attitude state measured by the Embedded GPS/INS system (EGI) and electronically steers the beam so that it remains perpendicular to the flight track throughout the data collection

  16. Scanning ARM Cloud Radar Handbook

    SciTech Connect

    Widener, K; Bharadwaj, N; Johnson, K

    2012-06-18

    The scanning ARM cloud radar (SACR) is a polarimetric Doppler radar consisting of three different radar designs based on operating frequency. These are designated as follows: (1) X-band SACR (X-SACR); (2) Ka-band SACR (Ka-SACR); and (3) W-band SACR (W-SACR). There are two SACRs on a single pedestal at each site where SACRs are deployed. The selection of the operating frequencies at each deployed site is predominantly determined by atmospheric attenuation at the site. Because RF attenuation increases with atmospheric water vapor content, ARM's Tropical Western Pacific (TWP) sites use the X-/Ka-band frequency pair. The Southern Great Plains (SGP) and North Slope of Alaska (NSA) sites field the Ka-/W-band frequency pair. One ARM Mobile Facility (AMF1) has a Ka/W-SACR and the other (AMF2) has a X/Ka-SACR.

  17. Scanning Probe Microscopy of Graphene

    NASA Astrophysics Data System (ADS)

    Tautz, Pamela

    2011-10-01

    Scanning tunneling microscopy has been used to study the unusual electronic properties of graphene. In an effort to support the graphene with minimal interaction with the substrate, we used a hexagonal boron nitride (hBN) substrate. To minimize contaminants between the CVD graphene and boron nitride, the graphene samples were cleaned with distilled water and isopropanol prior to transfer to hBN substrate. We have also examined the growth of graphene flakes by chemical vapor deposition. In particular, we examined the relationship between the orientations of the first and second layer of CVD grown graphene. We found the growth mechanism preferentially resulted in rotations of 9^o or less indicating flakes with first and second layers aligned.

  18. Scanning Electrochemical Microscopy in Neuroscience

    NASA Astrophysics Data System (ADS)

    Schulte, Albert; Nebel, Michaela; Schuhmann, Wolfgang

    2010-07-01

    This article reviews recent work involving the application of scanning electrochemical microscopy (SECM) to the study of individual cultured living cells, with an emphasis on topographical and functional imaging of neuronal and secretory cells of the nervous and endocrine system. The basic principles of biological SECM and associated negative amperometric-feedback and generator/collector-mode SECM imaging are discussed, and successful use of the methodology for screening soft and fragile membranous objects is outlined. The drawbacks of the constant-height mode of probe movement and the benefits of the constant-distance mode of SECM operation are described. Finally, representative examples of constant-height and constant-distance mode SECM on a variety of live cells are highlighted to demonstrate the current status of single-cell SECM in general and of SECM in neuroscience in particular.

  19. Fast scanning mode and its realization in a scanning acoustic microscope.

    PubMed

    Ju, Bing-Feng; Bai, Xiaolong; Chen, Jian

    2012-03-01

    The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images obtained by using the conventional scan mode and fast scan modes are compared. The total scanning time is reduced by 29% of the two proposed fast scan modes. It will offer a better solution for high speed scanning without sacrificing the system stability, and will not introduce additional difficulties to the configuration of scanning measurement systems. They can be easily applied to the mechanical scanning measuring systems with different driving actuators such as piezoelectric, linear motor, dc motor, and so on. The proposed fast raster and square spiral scan modes are realized in SAM, but not specially designed for it. Therefore, they have universal adaptability and can be applied to other scanning measurement systems with two-dimensional mechanical scanning stages, such as atomic force microscope or scanning tunneling microscope. PMID:22462966

  20. Fast scanning mode and its realization in a scanning acoustic microscope

    SciTech Connect

    Ju Bingfeng; Bai Xiaolong; Chen Jian

    2012-03-15

    The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images obtained by using the conventional scan mode and fast scan modes are compared. The total scanning time is reduced by 29% of the two proposed fast scan modes. It will offer a better solution for high speed scanning without sacrificing the system stability, and will not introduce additional difficulties to the configuration of scanning measurement systems. They can be easily applied to the mechanical scanning measuring systems with different driving actuators such as piezoelectric, linear motor, dc motor, and so on. The proposed fast raster and square spiral scan modes are realized in SAM, but not specially designed for it. Therefore, they have universal adaptability and can be applied to other scanning measurement systems with two-dimensional mechanical scanning stages, such as atomic force microscope or scanning tunneling microscope.

  1. Laser Scanning Applications in Fluvial Geomorphology

    NASA Astrophysics Data System (ADS)

    Alho, P.

    2014-12-01

    During recent decades, the use of high-resolution laser scanning data in fluvial studies has rapidly increased. Airborne laser scanning (ALS) can be used to extensively map riverine topography. Laser scanning data have great potential to improve the effectiveness of topographical data acquisition and the accuracy and resolution of DTMs (Digital Terrain Models) needed in fluvial geomorphology. Airborne Laser Scanning (ALS) is applicable for mapping areas varying from reach to catchment scale and these data are, therefore, particularly suitable, especially for hydraulic modelling, mapping of flood inundation, and the detection of macro-scale fluvial geomorphology. With Terrestrial Laser Scanning (TLS) a spatial resolution of less than 1 mm and a range accuracy of few millimetres can be achieved. Mobile Laser Scanning (MLS) enables a remarkably faster survey approach compared to the conventional TLS method. One of the newest applications of MLS approaches involves a boat/cart/backpack -based mobile mapping system. This set-up includes laser scanning and imaging from a platform moving along a river course or floodplain and may be used to expand the spatial extent of terrestrial scanning. Detailed DTMs derived from laser scanning data can be used to improve the recognition of fluvial landforms, the geometric data of hydraulic modelling, and the estimation of flood inundation extents and the associated fluvial processes. Fluvial environments also offer challenges for the application of laser scanning techniques. Factors such as vegetation cover, terrain undulation, coarse surface materials and water surfaces may distort a laser scanning survey.

  2. Bone scanning in severe external otitis

    SciTech Connect

    Levin, W.J.; Shary, J.H. 3d.; Nichols, L.T.; Lucente, F.E.

    1986-11-01

    Technetium99 Methylene Diphosphate bone scanning has been considered an early valuable tool to diagnose necrotizing progressive malignant external otitis. However, to our knowledge, no formal studies have actually compared bone scans of otherwise young, healthy patients with severe external otitis to scans of patients with clinical presentation of malignant external otitis. Twelve patients with only severe external otitis were studied with Technetium99 Diphosphate and were compared to known cases of malignant otitis. All scans were evaluated by two neuroradiologists with no prior knowledge of the clinical status of the patients. Nine of the 12 patients had positive bone scans with many scans resembling those reported with malignant external otitis. Interestingly, there was no consistent correlation between the severity of clinical presentation and the amount of Technetium uptake. These findings suggest that a positive bone scan alone should not be interpreted as indicative of malignant external otitis.

  3. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and frequency converters used with scanning receivers. (a)...

  4. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and frequency converters used with scanning receivers. (a)...

  5. Scanning Tunneling Optical Resonance Microscopy

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Wilt, Dave; Raffaelle, Ryne; Gennett, Tom; Tin, Padetha; Lau, Janice; Castro, Stephanie; Jenkins, Philip; Scheiman, Dave

    2003-01-01

    Scanning tunneling optical resonance microscopy (STORM) is a method, now undergoing development, for measuring optoelectronic properties of materials and devices on the nanoscale by means of a combination of (1) traditional scanning tunneling microscopy (STM) with (2) tunable laser spectroscopy. In STORM, an STM tip probing a semiconductor is illuminated with modulated light at a wavelength in the visible-to-near-infrared range and the resulting photoenhancement of the tunneling current is measured as a function of the illuminating wavelength. The photoenhancement of tunneling current occurs when the laser photon energy is sufficient to excite charge carriers into the conduction band of the semiconductor. Figure 1 schematically depicts a proposed STORM apparatus. The light for illuminating the semiconductor specimen at the STM would be generated by a ring laser that would be tunable across the wavelength range of interest. The laser beam would be chopped by an achromatic liquid-crystal modulator. A polarization-maintaining optical fiber would couple the light to the tip/sample junction of a commercial STM. An STM can be operated in one of two modes: constant height or constant current. A STORM apparatus would be operated in the constant-current mode, in which the height of the tip relative to the specimen would be varied in order to keep the tunneling current constant. In this mode, a feedback control circuit adjusts the voltage applied to a piezoelectric actuator in the STM that adjusts the height of the STM tip to keep the tunneling current constant. The exponential relationship between the tunneling current and tip-to-sample distance makes it relatively easy to implement this mode of operation. The choice of method by which the photoenhanced portion of the tunneling current would be measured depends on choice of the frequency at which the input illumination would be modulated (chopped). If the frequency of modulation were low enough (typically < 10 Hz) that the

  6. Excitation-scanning hyperspectral imaging microscope.

    PubMed

    Favreau, Peter F; Hernandez, Clarissa; Heaster, Tiffany; Alvarez, Diego F; Rich, Thomas C; Prabhat, Prashant; Leavesley, Silas J

    2014-04-01

    Hyperspectral imaging is a versatile tool that has recently been applied to a variety of biomedical applications, notably live-cell and whole-tissue signaling. Traditional hyperspectral imaging approaches filter the fluorescence emission over a broad wavelength range while exciting at a single band. However, these emission-scanning approaches have shown reduced sensitivity due to light attenuation from spectral filtering. Consequently, emission scanning has limited applicability for time-sensitive studies and photosensitive applications. In this work, we have developed an excitation-scanning hyperspectral imaging microscope that overcomes these limitations by providing high transmission with short acquisition times. This is achieved by filtering the fluorescence excitation rather than the emission. We tested the efficacy of the excitation-scanning microscope in a side-by-side comparison with emission scanning for detection of green fluorescent protein (GFP)-expressing endothelial cells in highly autofluorescent lung tissue. Excitation scanning provided higher signal-to-noise characteristics, as well as shorter acquisition times (300  ms/wavelength band with excitation scanning versus 3  s/wavelength band with emission scanning). Excitation scanning also provided higher delineation of nuclear and cell borders, and increased identification of GFP regions in highly autofluorescent tissue. These results demonstrate excitation scanning has utility in a wide range of time-dependent and photosensitive applications. PMID:24727909

  7. Correcting nonlinear drift distortion of scanning probe and scanning transmission electron microscopies from image pairs with orthogonal scan directions.

    PubMed

    Ophus, Colin; Ciston, Jim; Nelson, Chris T

    2016-03-01

    Unwanted motion of the probe with respect to the sample is a ubiquitous problem in scanning probe and scanning transmission electron microscopies, causing both linear and nonlinear artifacts in experimental images. We have designed a procedure to correct these artifacts by using orthogonal scan pairs to align each measurement line-by-line along the slow scan direction, by fitting contrast variation along the lines. We demonstrate the accuracy of our algorithm on both synthetic and experimental data and provide an implementation of our method. PMID:26716724

  8. Correlation-steered scanning for scanning probe microscopes to overcome thermal drift for ultra-long time scanning.

    PubMed

    Zhang, Liansheng; Long, Qian; Liu, Yongbin; Zhang, Jie; Feng, Zhihua

    2016-07-01

    The thermal effect is one of the most important factors that influence the accuracy of nanoscale measurement and the surface topography of samples in scanning probe microscopes (SPMs). We propose a method called correlation-steered scanning, which is capable of overcoming three-dimensional thermal drifts in real time for ultra-long time scanned images. The image is scanned band by band with overlapping parts between adjacent bands. The vertical drift can be considered as linear and can thus be eliminated together with the tilt of the sample by applying the flattening method. Each band is artificially divided into several blocks for conveniently calculating lateral drifts on the basis of the overlapping area of adjacent bands through digital image correlation. The calculated lateral drifts are compensated to steer the scanning of the subsequent blocks, thus ensuring that all bands are parallel to one another. Experimental results proved that images scanned by the proposed method exhibited less distortions than those obtained from the traditional raster scanning method. The nanoscale measurement results based on the image obtained by the proposed method also showed high accuracy, with an error of less than 1.5%. By scanning as many bands as needed, the correlation-steered scanning method can obtain a highly precise SPM image of an ultra-large area. PMID:27107628

  9. Modulation transfer function of bar code scanning

    NASA Astrophysics Data System (ADS)

    Tang, Hong; Milster, Tom D.

    1998-09-01

    Bar code scanners are ubiquitous in supermarkets. As a bar code is passed over a scanner, a laser beam scans across the bar code. The scattered light is modulated by the reflectivity of the bars and spaces of the bar code. The bar code scanning process can be described as a 1D convolution of the scanning laser profile and the bar code reflectivity function. The modulation transfer function (MTF) of bar code scanning is the Fourier transform of the marginal profile of the laser beam. The properties of the MTF of bar code scanning is similar to that of an incoherent imaging system. Measurements of the MTF of bar code scanning at one focus position are presented. The experimental results are then discussed.

  10. Ion Implantation with Scanning Probe Alignment

    SciTech Connect

    Persaud, A.; Liddle, J.A.; Schenkel, T.; Bokor, J.; Ivanov, Tzv.; Rangelow, I.W.

    2005-07-12

    We describe a scanning probe instrument which integrates ion beams with the imaging and alignment function of a piezo-resistive scanning probe in high vacuum. The beam passes through several apertures and is finally collimated by a hole in the cantilever of the scanning probe. The ion beam spot size is limited by the size of the last aperture. Highly charged ions are used to show hits of single ions in resist, and we discuss the issues for implantation of single ions.