Focal differential diagnosis

In the vast majority of strokes, there is the sudden onset of focal symptoms without any other features. However, it is important to take a detailed history since occasionally there may be a more gradual onset of symptoms, thus widening the differential diagnosis, or there may be points in the history suggesting an underlying cause for the stroke or an indication that the presentation is of a condition mimicking stroke (Table 9.1). 

In the case of differential diagnosis of adenoma versus focal nodular hyperplasia, scintigraphy is indicated, whereas in the case of metastases, more reliable imaging techniques are preferred, (s. fig. 9.4)... 

Chickenpox in infancy and shingles in adults are caused by the same varicella-zoster virus. Very rarely and almost exclusively in immunosuppressed patients, concomitant hepatitis can occur with pronounced (mainly focal) hepatocellular necrosis, sometimes even with a fatal course. (37) Leucocytic portal and periportal infiltration can spread to the blood vessels and bile capillaries. Intranuclear inclusion bodies are present (s. fig. 23.2). Diagnosis is based on increased GPT, GOT, GDH and y-GT values as well as the presence of varicella IgM antibodies alternatively, pathogens can also be demonstrated in cultures. In children, a differential diagnosis of Reye s syndrome must be considered. As therapy in a severe course, aciclovir is indicated. (38-43)... 

A so-called porcelain liver should be clarified by differential diagnosis. (188) This condition is characterized by focal calcareous deposits in the liver capsule, which can be detected by X-ray examination as well as by sonography and CT. It may be caused by phleboliths, pseudolipoma, histoplasmosis, calcified larvae, small capsule haematomas, small abscesses, etc. 

Immunohistochemically, CKs are expressed in the well-formed epithelial component however, the sarcomatoid component might be negative or focal/weak positive, hindering the differential diagnosis with sarco-mas.28,156,157 should be kept in mind that sarcomas... 

Three-dimensional images can be reconstructed from a power US study, with or without administration of contrast media, and visualized as a dne loop. The intratumoral blood-flow of focal liver lesions can thus be visualized and can be useful for the differential diagnosis of hepatic tumors, especially HCC and FNH. In fact, these tumors have distinctly different intratumoral vascular structures (Hirai et al. 1998 Cesarani et al. 1999 Campani et al. 1998). Three-dimensional power Doppler US can effectively depict the associated arteries of HCCs, and there is a good correlation with angiographic study (Liang et al. 2003). 

Van Hoe L, Baert AL, Gryspeerdt S etal. (1997) Dual-phase helical CT of the liver value of an early-phase acquisition in the differential diagnosis of noncystic focal lesions. AJR Am J Roentgenol 168 1185-1192 Verdun FR, Noel A, Meuli R et al. (2004) Influence of detector collimation on SNR in four different MDCT scanners using a reconstructed slice thickness of 5 mm. Eur Radiol 14 1866-1872... 

Table 19.2. Differential diagnosis of sonographic renal changes (adapted from Perale 1992 Hoyer 1996). The typical sonomorphical appearances of various renal diseases with some hints for differential diagnosis are listed in 3 tables (Table 19.2a normal parenchymal pattern, but different renal size Table 19.2b diffuse parenchymal abnormalities Table 19.2c focal renal parenchymal alterations). Some entities...

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