Measurement of D-dimer is a significant tool for detecting hypercoagulation in thrombotic diseases. However, the role of D-dimer in thrombotic diseases in elderly patients is still unclear. We measured plasma D-dimer, prothrombin fragment 1 + 2, fibrinogen, thrombin-anti-thrombin III, thrombomodulin, protein C, tissue plasminogen activator-tissue plasminogen activator inhibitor 1 complex and serum lipids in patients with thrombotic diseases (57 cases total, 19 men, 38 women ; age range 64〜92,76.6 ± 7.6 (mean ± SD)). Their diseases included cerebral infarction, 31 ; ischemic heart diseases, 23 ; leg artery thrombosis, 2 ; abdominal aneurysm 1. The plasma D-dimer level in the thrombotic diseases was 213.82 ± 170.46 ng/ml There was no significant difference in plasma D-dimer level between cerebral infarction patients and ischemic heart disease patients. D-dimer correlated with fibrinogen (r = 0.47, p < 0.001), prothrombin fragment 1 + 2 (r = 0.59, p < 0.001), and age (r = 0.39, p < 0.01). D-dimer did not correlate with thrombomodulin, thrombin-antithrombin III, protein C, tPA-PAIC, total cholesterol, triglyceride, HDL or LDL. To clarify the cause of high levels of D-dimer in thrombotic diseases, we examined the aortas of 8 patients showing over 400 ng/ml of D-dimer by ultrasonography and detected 5 abdominal aortic aneurysms. D-dimer elevated with increasing size of the aortic aneurysm. It was concluded that D-dimer was a significant tool for detecting hypercoagulation in thrombotic diseases and aneurysm should be investigated in patients with a high level of D-dimer.

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An implant material containing albekacine sulfate, polylactic acid and calcium phosphate was made, and in vitro and in vivo experiments were performed using the material. In vitro slow release tests of antibiotics were performed by the total volume exchange method using cylindrical implants. Model rats with osteoporosis were produced for in vivo experiments, and the bone mineral density was measured 1, 2, 4 and 6 months after injection of the implant into the femur in the osteoporosis, sham surgery and non-treated groups. Simultaneously, tissue samples were collected and observed. In the in vitro slow release tests, the concentration was higher than the minimal inhibitory concentration of abreacting against the growth of methicillin resistant Staphylococcus aureus (MIC80) was maintained for 18 days. In all in vivo experiment groups, the bone mineral density on the implant-injected femur slightly increased with age. Histologically, the implant was in close contact with the bone cortex one month after surgery and maintained until 6 months after surgery. It was concluded that the implant material is widely applicable as a biomaterial in clinical fields such as the treatment of fractures caused by osteoporosis and the filling and reinforcement of bone defects after treatment of infection lesions and bone fusion with artificial joints.

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To clarify the indications for CSF shunting in normal pressure hydrocephalus (NPH) following subarachnoid hemorrhage (SAH), the author investigated changes in the pulsatile brain motions during a cardiac cycle in 17 cases with ventriculomegaly following SAH on cardiacgated cine MR images comparing with those in 50 normal adults. In 15 of these seventeen cases, the lateral ventricles not only constricted immediately following the R-wave related to brain expansion but also expanded paradoxically over the initial size during a cardiac diastole. These patterns were different from those of normal adults, and eleven of them showed excellent response to CSF shunting. Theses findings in ventricular motion during a cardiac cycle indicate that the forceful intraventricular CSF flows and stagnancy expand the ventricular walls causing compression of the surrounding brain against the skull. In the remaining two, the lateral ventricles only constricted immediately following the R-wave and the ventricular size change was similar to those of normal adults, and they were diagnosed as not requiring CSF shunting. Assessing ventricular size change on cine-MR enables non-invasive differentiation of NPH from other form of ventriculomegaly, and evaluation of the benefit of CSF shunting is also possible by this technique preoperatively.

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