CT-Guided Interventions
CT-Guided Interventions It is not always possible to determine the nature of a lesion from CT appearance and densitometry alone. In these cases, needle biopsies may be carried out under…
Radiation Safety
Radiation Safety The physical radiation dose D (energy absorbed per unit mass) is expressed in Gray (Gy), used for any type of radiation and also in the radiation therapy of…
Cranial CT: Normal Findings
Cranial CT: Normal Findings The scan usually begins at the base of the skull and continues upward. Since the hard copies are oriented such that the sections are viewed from…
Cervical Pathology
Cervical Pathology Enlarged cervical LNs ( Fig. 70.1a ) appear conspicuously as isolated nodular masses (6) that cannot be followed into adjacent levels (see p. 15). Large lymphomas (7) or…
Cervical CT
Cervical CT Whenever there is no contraindication, CT examinations of the neck are carried out after i.v. administration of CM. Malignant and inflammatory processes can be depicted more accurately with…
Cranial Pathology
Cranial Pathology After having discussed that partial volume effects due to asymmetric projections (i.e., 55b in Fig. 54.2b ) may be misinterpreted as acute hematomas, this chapter will point out…
ABC-Primer of CT Evaluation
ABC-Primer of CT Evaluation Occasionally, the beginner faces the question to decide whether a finding represents a true lesion or just an artifact. A contralateral comparison or a comparison with…
Physical and Technical Fundamentals
Physical and Technical Fundamentals General Principles of CT Computed tomography is a special type of x-ray procedure that involves the indirect measurement of the weakening, or attenua-tion, of x-rays at…
Basic Rules of Reading CT Examinations
Basic Rules of Reading CT Examinations Anatomic Orientation An image on the display is not only a 2D representation of anatomy, it contains information about the mean attenuation of tissue…
Administration of Contrast Agents
Administration of Contrast Agents Contrast-Enhanced CT-Scans and Contrast Media To achieve high-image quality for diagnostic approaches, radiologists perform most CT-examinations as contrast-enhanced scans. Only a minority of CT-exams (e.g., stone…
