Computed tomography , measuring

Carmignato S (2012) Accuracy of industrial computed tomography measurements experimental results from an international comparison. CIRP Ann Manuf Technol 61(l) 491-494... 

S. Ontiveros, J.A. Yagiie-Fabra, R. Jimenez, G. Tosello, S. Gasparin, A. Pierobon, S. Carmignato, H.N. Hansen. Dimensional Measurement of micro moulded parts by Computed Tomography. Measurement Science and Technology. 23 (2012) 125401. 

The key company of the new NDT- centre is HAPEG (Hattinger Priif- und Entwicklungs-gesellschaft), which operates a Computed Tomography system and offers service measurements on test samples of their customers [1]. The basic set up and technical details of this CT-system are presented in this paper. Details of the extension towards 3D visualisation, 3D-Tomography and the software involved are presented in a different paper [2]. 

A Similar aphical presentation of the spatial distribution of a tracer g is or a real contaminant and thereby to some extent the airflow in the studied area is based on the use of computed tomography and optical remote sens-jt]g I2.M beams are sent out horizontally and reflected back to an IR analytical instrument, analyzing the average concentration of the contaminant along the IR beam. By combining data from several measured tines it is possible ro present data in a similar way to Fig. 12.8. Those methods presuppose access ro an expensive and complicated sampling/data processing system. 

Sakai F, Nakazawa K, Tazaki Y, Ishii K, Hino H, Igarashi H, Kanda T. Regional cerebral blood volume and hematocrit measured in normal human volunteers hy single-photon emission computed tomography. J Cereb Blood Flow Metab 1985 5 207-213. 

Wintermark M, Reichhart M, Thiran JP, Maeder P, Chalaron M, Schnyder P, Bogous-slavsky J, MeuU R. Prognostic accuracy of cerebral blood flow measurement by perfusion computed tomography, at the time of emergency room admission, in acute stroke patients. Ann Neurol 2002 51 417-432. 

Magnetic resonance imaging (MRI) or computed tomography (CT) is used to measure changes in brain size and volume and rule out stroke, brain tumor, or a cerebral edema. 

Bone mineral density can be measured at various sites throughout the skeletal system and by various methods. The site of measurement can be either central (hip and/or spine) or peripheral (heel, forearm, or hand). Dual-energy x-ray absorptiometry (DXA) can be used to measure central and peripheral sites of bone mineral density. Quantitative ultrasound, peripheral quantitative computed tomography, radiographic absorptiometry, and single-energy x-ray absorptiometry are used to measure peripheral sites. 

Merkel OM, Librizzi D, Pfestroff A, Schurrat T, Buyens K, Sanders NN, De Smedt SC, Behe M, Kissel T (2009) Stability of siRNA polyplexes from poly(ethylenimine) and poly (ethylenimine)-g-poly(ethylene glycol) under in vivo conditions effects on pharmacokinetics and biodistribution measured by Fluorescence Fluctuation Spectroscopy and Single Photon Emission Computed Tomography (SPECT) imaging. J Control Release 138 148-159... 

Malison, R. T., Price, L. H., Berman, R. et al. Reduced brain serotonin transporter availability in major depression as measured by [123I]-2(3-carbomethoxy-3(3-(4-iodophenyl)-tropane and single photon emission computer tomography. Biol. Psych. 44 1090-1098,1998. 

Finally, newer scanners are being developed with both PET and another modality, such as computed tomography (X-ray CT), where a subject would be scanned first with X-ray CT for anatomy and for attenuation correction, and then imaged for their PET or SPECT measurements. 

Genant HK, Lang T, Fuerst T, Pinette KV, Zhou C, Thiebaud D, Dfez-Perez A (2004) Treatment with raloxifene for two years increases vertebral bone mineral density as measured by volumetric quantitative computed tomography. Bone 35 1164-1168... 

Most contrast agents elicit nephrotoxicity because they are primarily excreted by the kidneys. However, when administered in small doses, they constitute a rich source of GFR markers. The two major classes of contrast agents that are finding clinical utility as GFR markers are iodinated aromatic compounds and metal complexes. lodinated aromatics such as iohexol and iothalamate (Fig. 13) are commonly used as contrast agents for computed tomography (GT). They also have pharmacokinetics similar to inulin and hence are useful indicators of renal status [215]. The iodinated molecules used for GFR measurements consist of a triiodo-benzene core and hydrophilic groups to enhance solubility in aqueous medium. 

Malison, R.T., Price, L.H., Berman, R., van Dyck, C.H., Pelton, G.H., Carpenter, L., Sanacora, G., Owens, M.J., Nemeroff, C.B., Rajeevan, N., Baldwin, R.M., Seibyl, J.P., Innis, R.B., and Char-ney, D.S. (1998) Reduced brain serotonin transporter availability in major depression as measured by [1231]-2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane and single photon emission computed tomography. Biol Psychiatry 44 1090-1098. 

Proper control of food irradiation applications should fulfill the requirements for both food technologies and radiation technologies. Application of well-established methods for measurement of absorbed radiation dose and the dose distribution helps to provide assurance that the radiation treatment is both effective and legally correct [133]. Computer tomography (CT) can provide detailed, high-resolution, and accurate dose maps for any arbitrary product and package configurations [134]. Such dose maps are an essential part of process validation. 

D haenen HA, Bossuyt A Dopamine D2 receptors in depression measured with single photon emission computed tomography. Biol Psychiatry 35 128-132, 1994 Di Costanzo E, Schifano E Dthium alone or in combination with carbamazepine for the treatment of rapid-cycling bipolar affective disorder. Acta Psychiatr Scand 83 456-459, 1991... 

Schlegel S, Kretzschmar K Computed tomography in affective disorders, part 1 ventricular and sulcal measurements. Biol Psychiatry 22 4-14, 1987 Schmauss M, Laakmann G, Dieterle D Effects of cXj-receptor blockade in addition to tricyclic antidepressants in therapy-resistant depression. J Clin Psychopharmacol 8 108-111, 1988... 

In computer tomography the patient to be examined lies within a circle of detectors (up to 1200) [5.428]. A continually irradiating X-ray tube rotates around the patient. The detectors measure the intensity of the X rays which have passed through a particular layer of the body. They consist of a phosphor crystal (CdW04 and Bi4Ge3012, lmax 480 nm) which is combined with a photodiode. 

---