48. The resolution of imaging system refers to the amount of detail which is observable
49. It may be formulated as the number of pairs of black and white lines which an image forming or image recording device can demonstrate in a length of 1 mm
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58. The magnification difference at the peripheryof the image results from the projection of the x-ray beam ontoa curved input surface.
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64. To increase image contrast, contrast agents, which are dense fluids with elements of high atomic numbers, such as iodine, are injected into a blood vessel during angiography. Because of its higher density and high atomic number, iodine absorbs photons more than blood and tissue.
174. Three-dimensional (3D) reconstruction of the dataset acquired during rotational DSA represents the latest development in the neurovascular imaging armamentarium.
175. This technique combines the anatomic resolution of DSA with the 3D visualization abilities previously offered by only CT or MR angiography and provides more detailed information than does DSA alone in the evaluation of neurovascular lesions, such as cerebral aneurysms .
176. 3D-DSA has taken a prominent role in treatment planning by enabling better appreciation of the morphology of complex vascular lesions before endovascular or surgical management.
177. It is also superior in the performance of sophisticated tasks such as aneurysm volume measurement