Background: Cardiac surgery requires the placement of drains in the mediastinum, pericardial space, and pleural spaces at the end of the procedure. Recently, small, flexible, fluted silicone drains have been widely used after cardiac surgery. Although preliminary reports suggest that small silastic drains are superior to conventional rigid large-bore chest tubes, there has been no experimental comparison of the drainage capacity of these drains under similar conditions. To compare the efficacy of smaller silastic drains and conventional chest tubes, a three-part in vitro and two-part in vivo experiment was performed.
Methods: In the first part of the in vitro study, the drainage capacity of 19-F silicone drains and 28-F conventional tubes was tested under steady flow. Both tubes were placed in a water bath and drained at a pressure of 10mm Hg. In the second part of the in vitro study, the drainage pattern was also visualized. Finally, an anatomically identical apparatus, consisting of a silicone ventricle and a latex-rubber pericardium, was employed to simulate drainage under clinically similar conditions. In the in vivo study, 19-F and 24-F silicone drains and 28-F and 32-F conventional tubes were inserted into the hemithorax or pericardial space of 12 adult pigs. Blood was infused into both chest cavities or pericardial spaces, and the tubes were drained at 15cmH₂O.
Results: In the in vitro study, the drainage capacity of the conventional chest tubes was 7 times greater than that of the smaller silicone drains. However, in the in vivo pleural drainage test, the drainage capacity of the smaller silicone drains was greater than that of the conventional chest tubes. Additionally, in the in vivo pericardial drainage test, there was no difference in drainage capacity between the two types of tube. Furthermore, the flow visualization test revealed different drainage patterns in the two tubes and showed that the most effective portions were the most proximal slits of the silicone drain and the side holes of the conventional chest tube. However, in the in vitro pericardial model, there was no difference in drainage capacity between the two types of tube, as the slits or side holes were completely within the pericardial cavity.
Conclusions: This experiment demonstrated that the smaller silastic chest drains have a sufficient drainage capacity that is almost identical and possibly superior to that of conventional chest tubes.

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A stroke care unit (SCU) was established at the Nippon Medical School Main Hospital on May 6, 2005. We performed a retrospective analysis of clinical data for patients with acute ischemic stroke. From among patients who were admitted to our ward, including the SCU, from May 6, 2005, through April 30, 2006, we selected 241 consecutive patients with acute ischemic stroke who could be classified by stroke subtype. An unfavorable outcome at that associated with a discharge was defined as modified Rankin Scale score of 3 or greater. We used logistic regression to identify factors that were independently and significantly related to an unfavorable outcome at discharge. Hypertension (odds ratio [OR]=3.446; confidence interval [CI]=1.195 to 9.934), valve disease (OR=3.694 CI=1.092 to 12.502), and NIH Stroke Scale score (OR=1.322 CI=1.175 to 1.450) were independent determinants of an unfavorable outcome at discharge. Smoking (OR=0.298 CI=0.105 to 0.848) was an independent determinant of a favorable outcome at discharge. No medical treatments were independent determinants for unfavorable or favorable outcomes at discharge. Education about stroke prevention, shortening of patient transport time, and emergency magnetic resonance imaging, including diffusion-weighted imaging, are needed to decrease the frequency of unfavorable outcomes at discharge.

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Fluorodeoxyglucose (FDG) is the most commonly utilized positron emission tomography (PET) tracer and has demonstrated utility in oncology. FDG-PET imaging is extremely useful in diagnosing, staging, and monitoring response to treatment in a variety of cancers. However, PET imaging is limited in its ability to assign molecular abnormalities to specific anatomical structures. This limitation has been recently overcome by the appearance of PET/CT system. This image fusion has tremendous potential because it combines the most sensitive 'functional image' with the highest resolution 'structural image'. This fusion imaging is essential for accurate diagnosis of molecular disorders.
CT angiography (CTA) offers a valuable alternative for the diagnosis of coronary artery disease (CAD). However, it is well established that a comprehensive assessment of CAD requires not only morphologic information but also 'functional information'. Thus, assessment of the functional relevance of coronary stenosis, such as stress myocardial perfusion single photon emission computed tomography (SPECT), is extremely important to guide further decisions about revascularization. In the present study, 3D fused cardiac SPECT/CT images were generated. The additional utility of fused imaging was obtained in the diagnosis of culprit arteries in patients with multi-vessel disease, along with a functional assessment of vessels with heavy calcification on CTA. This fusion imaging provides useful diagnostic information on the function relevance of coronary artery lesions.

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Recent studies have shown that adult neurogenesis in the dentate gyrus of the hippocampus is required for the behavioral effects of antidepressant drugs in rodents and is possibly involved in the etiology of psychiatric disorders. The synapses between mossy fibers, axons of the dentate gyrus granule cells, and hippocampal CA3 pyramidal cells are characterized by prominent synaptic facilitation, an activity-dependent increase in synaptic efficacy. Changes in mossy fiber synaptic transmission, especially its activity-dependent nature, can greatly affect the operation of CA3 neural circuits. Because the magnitude of this synaptic facilitation has been shown to change during development, the generation of new neurons in the dentate gyrus may affect signal transmission mediated by mossy fibers. Abnormal projection and density of mossy fibers have been demonstrated in patients with psychiatric disorders. For these reasons, alterations in mossy fiber synaptic transmission may be involved in the pathophysiology of psychiatric disorders. The mossy fiber synapse is a potential target for developing new pharmacological treatments for psychiatric disorders.

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Thymic hyperplasia commonly presents in association with Grave's disease. We report on a patient in whom Grave's disease was diagnosed after thymectomy. The patient, a 53-year-old man, was initially suspected to have thymoma, thymectomy was performed. Tachycardia and a high-grade fever developed immediately after surgery, suggesting thyroid crisis. The patient was treated with antithyroid drugs and beta blockers. The patient's condition improved thereafter, and the patient was discharged on the 18th hospital day. Histopathological examination of the resected thymic tissue revealed thymic hyperplasia. To our knowledge, there have been no reported cases of Grave's disease which had not been detected until the development of postoperative thyroid crisis, as in our patient. Therefore, we report this case with discuss the treatment performed.

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Anomalous systemic arterial supply to the basal segment of the left lung (ABLL) is a rare congenital disorder in which an aberrant artery arising from the descending thoracic aorta supplies the basal segment of the left lower lobe, which is then drained through the normal pulmonary vein. We report two cases of ABLL treated at Nippon Medical School Chiba Hokusoh Hospital. The first patient was a 56-year-old woman who was admitted to our hospital because of hemoptysis. ABLL was suspected on the basis of computed tomography of the chest. The second patient was a 22-year-old man who was admitted to the emergency room of another hospital presenting with severe hemoptysis due to a contusion of the back, and was then transferred to our hospital after the symptoms improved. ABLL was diagnosed in both patients by means of bronchoscopy and angiography (aortography and pulmonary arteriography). Left lower lobectomy and ligation of aberrant artery were successfully performed.

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Lissencephaly is a type of cortex convolution malformation caused by a neuronal migration disorder in early fetal development. It is characterized by a thick cortex and agyria (absence of gyri) or pachygyria (broad gyri) on the brain surface. Clinical manifestations include severe mental retardation and intractable epilepsy. Here, we report a four months old boy with lissencephaly started focal seizures in a patient aged 3 months who was treated with 2 anticonvulsants. Spasms and regression of psychomotor development were present from 6 months of age. West syndrome was diagnosed on the basis of the types of seizures and electroencephalographic findings (hypsarrhythmia). Treatment with ACTH was started in an attempt to control the spasms. Decreases in convulsive seizures and recovery of regressed psychomotor development were subsequently noted. However, convulsive seizures recurred when the ACTH was tapered. The epileptic seizures accompanying lissencephaly thus appear to be intractable.

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A 69-year-old woman was admitted to our hospital for the treatment of a dorsal pancreatic artery aneurysm detected with abdominal computed tomography. Angiography revealed celiac axis occlusion, a large aneurysm in the dorsal pancreatic artery, and small aneurysms in the celiac and splenic arteries. Transcatheter arterial embolization with microcoils, N-butylcyanoacrylate, and lipiodol was successfully performed for the dorsal pancreatic artery and the aneurysm. In the 2 years after treatment the dorsal pancreatic artery aneurysm has not recurred, and other aneurysms have not enlarged.

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