Portal anomalies

Explosives may reside on a person in the form of trace (residue from handling explosives, exposure to explosives, or hidden explosives) and/or bulk (a large mass of explosives). The portal technologies that enable the detection of these two forms of explosives may be categorized as trace and anomaly. The detection methods utilized by these two types of portals are substantially different in the signature of the material detected and the... 

Anomaly portals detect an irregularity caused by the bulk explosive (or other contraband) and its location on the person and then provide visual information to the operator. Anomaly portals detect masses of objects (i.e., guns and knives), including explosives, concealed beneath clothing but external to the body. To detect these masses, some anomaly portals utilize imaging techniques such as X-rays or millimeter waves to provide visual information. Another anomaly portal uses dielectric changes to detect masses. Currently, anomaly portals do not identify the particular explosive (a chemical characteristic) or other type of contraband. Operators interpret the data provided by the portal to make a judgment about the source of the alarm. 

Trace portals could also be used for bulk detection because of the likelihood that a mass of explosive concealed on the person would present an adequate chemical signature. The combination of a trace and anomaly portal would provide a powerful multi-sensor platform that would offset the limitations of the individual technologies. Currently, a commercially available multi-sensor explosives detection personnel portal that combines trace and anomaly methods does not exist. 

Anomaly portals have two factors that have affected public acceptance of the associated technologies radiation (both ionizing and non-ionizing) exposure and privacy concerns, despite verification of safe levels of radiation and advances in technology... 

Figure 8 is an X-ray image from the portal. The system reveals a variety of anomalies on the body such as explosives, narcotics, metal guns and knives, and weapons made of plastic or ceramic. AS E offers privacy software to address the subject s concerns about images that are too revealing. 

The People Portal II (PPII), manufactured and marketed by EMIT Technologies LLC, identifies anomalies on a person s body by detecting changes in the dielectric constant within a defined space [60], Figure 11 shows the People Portal II, which is based on a proprietary microwave technology platform called Electro-Magnetic Impedance Translation (EMIT). 

Combining trace and anomaly technologies will provide a powerful detection system that would be very difficult to defeat. In the recent past, the portals highlighted in this chapter existed only as an idea, one-of-a-kind, or laboratory novelty, and now all are commercially available portals. Researchers will develop new portal systems as detectors, methods, and threats change. 

A drastic reduction in numbers of interlobular bile ducts is termed ductopenia (or paucity of bile ducts). Ductopenia is considered to be present if the ratio of interlobular ducts to the number of portal tracts is <0.5 (normal value 0.9-1.8), i.e. in a sufficiently large biopsy specimen, no more than half of the portal fields should be without a bile duct. Ductopenia can appear as an isolated defect (non-syndromic) or in combination with other extrahepatic (syndromic) anomalies. Non-syndromic paucity constantly exhibits bile-duct dilatation with blunting of microvilli. Idiopathic neonatal hepatitis sometimes overlaps with non-syndromatic ductopenia. Children with ductopenia may survive into adulthood. (504) (s. fig. 32.16)... 

Portal vein diseases may be congenital or acquired, or arise as a sequela of portal hypertension (1.) portal vein anomalies, (2.) pylephlebitis, and (5.) portal vein thrombosis. 

Congenital anomalies of the portal vein are very rare. This also applies to accessory portal veins with their individually varying patterns. 

Anomalies are described as a missing portal vein and intrahepa-tic branches with simultaneous hyperplasia of the hepatic artery. The portal vein and its branches may also be located in front of the duodenum and the pancreatic head. Sometimes, even a... 

In addition to the congenital anomalies, other clinical features may be responsible for disorders of the portal vein system ... 

Acquired causes may also be responsible for some of the congenital anomalies described above. Mention should be made of (1.) arterioportal fistulas, (2.) cavernous transformation of the portal vein (in portal vein thrombosis), (3.) fibrous obliteration of the portal vein, and (4.) cicatricial portal vein stenosis. These may also cause prehepatic hypertension, (s. tab. 14.2) (s. p. 246 )... 

The presence of so many anomalies in the literature and folklore of psychedelia favors an alchemical interpretation, that is to say, the consciousness we seek to alter is at least as important as the substance we use to alter it with. The same key may open many different doors, but what might lie behind each portal will remain indeterminate until entered. There are valid reasons for Western medicine s preference for... 

Other congenital anomalies such as polysplenia, midline liver, interrupted inferior vena cava, situs inversus, preduodenal portal vein, and intestinal... 

Mesenchymal hamartomas are considered to be a developmental anomaly more than true neoplasm. A total of 75% of cases are located in the right lobe of the liver. Histologically MHR arise from the mesenchyma of the portal tract and will have connective tissue, blood vessels, lymphatic spaces, bile ducts and normal hepatocytes (Konez et al. 2001 Cetin et al. 2002). 

Preduodenal portal vein (PPV) is a rare congenital anomaly associated with additional various anomalies, including intestinal malrotation, situs anomalies, IVC anomalies, polysplenia, pancreatic anomalies, duodenal atresia, and cardiac anomalies (Tsuda et al. 1991 Gayer et al. 1999). On CT, the preduodenal and prepancreatic localization of the portal vein is demonstrated, as well as any associated anomalies (Fig. 9.5). The diagnosis of a PPV before surgical intervention in the upper abdomen is important to prevent its inadvertent ligation or transection (Tsuda et al. 1991). 

Fig. 9.5. Preduodenal portal vein (arrowhead) is seen crossing laterally to the descending part ofthe duodenum (arrow) in a patient with associated congenital anomalies of situs inversus and interrupted IVC (Reprinted with permission from Gayer et al. 1999)...

Contraindications toliver transplantation include uncontrolled active extrahepatic sepsis, advanced cardiorespiratory disease, extrahepatic malignancy, active substance abuse, medical non-compliance, and significant irreversible brain injury. A history of previous abdominal surgery, the presence of portal vein thrombosis, or congenital anomalies of the inferior vena cava are no longer considered a barrier to transplantation. Co-infection with human immunodeficiency virus is also no longer considered... 

---