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This paper shows four statistical methods that examine the distribution of points on a network (such as the distribution of retail stores along streets). The first statistical method is an extension of the nearest-neighbor distance method (the Clark-Evans statistic) defined on a plane to the method defined on a network. The second statistical method examines the efect of categorical attribute values of links (say, types of streets) on the distribution of activity points on a network. The third statistical method examines the effect of infrastructural elements (such as railway stations) on the distribution of activity points on a network. The fourth statistical method examines the compound effect of multiple kinds of infrastructural elements (say, railway stations and big parks) on the distribution of activity points on a network. These methods are discussed with empirical examples.

Accurate preoperative assessment of pulmonary function is a valuable indicator of postoperative morbidity.

Hepatopulmonary syndrome (HPS) (hypoxaemia due to intrapulmonary vasodilation and a right-to-left shunt associated with liver disease) resolves after liver transplantation. The authors describe a case of spontaneous resolution of HPS prior to liver transplantation. This patient was diagnosed with HPS associated with extra-hepatic biliary atresia when she was 10 years old. She exhibited digital clubbing, facial vascular dilation, cyanosis, and suffered from dyspnoea during exercise. The patient's PaO(2) at rest was 53.8 mm Hg in room air and a Technetium-99m macro-aggregated albumin lung perfusion scan demonstrated a right-to-left shunt. Although her symptoms and laboratory data supported a diagnosis of HPS, she nevertheless showed spontaneous resolution within 2 years. When she was 14 years old, pulmonary hypertension was evident upon examination of her echocardiogram. HPS may be improved or masked by an accidental overlap with pulmonary hypertension in the terminal stage of liver disease.

The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.