Relationship of Spinal Fracture to Bone Density,Textural, and Anthropometric Parameters

To investigate risk factors for spinal fracture, we studied the relationship between the prevalence of asymptomatic spinal fracture and various morphological measures including spinal bone mineral density (BMD) in women. A total of 122 women ranging in age from 55 to 79 years were studied. The group consisted of 46 women aged 55–59 years (18 with fracture), 51 women aged 60–69 years (26 with fracture), and 26 women aged 70–79 years (14 with fracture). BMD of cortical and trabecular bone from L1 to L3 was measured using quantitative computed tomography (QCT). Run-length analysis was applied to evaluate the spinal trabecular textural features using CT images; the texture indices which represent the mean width of trabeculae (the T-texture) and that of intertrabecular spaces (the I-texture) were obtained. Anthropometric factors including body weight and height, psoas muscle area, and vertebral bone volume were measured using CT images. Among the various factors, trabecular BMD in women aged 55–69 years showed the highest odds ratio for the presence of fracture per standard deviation (SD) decrease in bone density. However, in women aged 70–79 years, the highest odds ratio was observed for trabecular texture index but not for trabecular BMD. The I-texture in women aged 55–59 years, the muscle area in women aged 60–69 years, and cortical BMD and muscle area in women aged 70–79 years were also considered significantly related to the risk of fracture. Received: 31 December 1995 / Accepted: 24 July 1996     

The strategy of thoracic endovascular repair for aortic arch aneurysms

Thoracic endovascular aneurysm repair (TEVAR) has gained wide acceptance because of its minimal invasiveness and effectiveness for thoracic aortic aneurysms. However, the endovascular technique alone is often not applicable to arch aneurysms due to their anatomical complexity, such as aortic curve and presense of neck branches. The development of branched stent graft that allows total endovascular approach has been slow. Therefore open surgical technique is still needed to obtain an adequate landing zone. Prior total arch replacement with elephant trunk and debranching neck vessels including partial debranching such as carotid-carotid crossover bypass, and total debranching from the ascending aorta were able to create a suitable proximal landing zone. Chimney technique using covered stent for the neck vessels is also effective for arch aneurysms. Here, we report the strategies of TEVAR for aortic arch aneurysms.     

The temperature measurement of infusion fluid by infrared thermometer is useful for safety in infusion therapy

BACKGROUND: The measurement of infusion fluid temperature is important for patients' thermoregulatory management. However, we usually estimate the temperature by touching and feeling the surface of the infusion bag. Accordingly, there is increasing demand for more quantitative method to measure infusion fluid temperature. METHODS: In the operating room we evaluated the accuracy and precision of the infrared thermometer (Genius) for the measurement of infusion fluid temperature compared with the thermistor. RESULTS: The fluid temperature measured by Genius is accurate with sufficient precision compared with that measured by thermistor. CONCLUSIONS: The temperature measurement of infusion fluid by infrared thermometer is clinically helpful and useful for patients' safety.     

Emergency stent placement after descending aortic replacement with chronic aortic dissection

A 49-year-old man with asymptomatic chronic aneurysmal dissection was admitted to our hospital. He had undergone ascending aortic replacement for type A aortic dissection 7 months before. We performed descending aortic replacement for chronic aneurysmal dissection. Renal dysfunction appeared 1 day after the operation. Contrast-enhanced computed tomography indicated that the true lumen was severely compressed by a false lumen, and that the origins of the renal artery were occluded. We performed emergency endovascular stent placement to dilate the true lumen. Immediately after this procedure, renal ischemia improved. The postoperative course was uneventful. An endovascular approach using bare stent can be a treatment option that is less invasive and prompter for a patient with renal ischemia resulting from aortic dissection.     

Nose/mouth distribution of respiratory airflow in 'mouth breathing' children

Oro-nasal distribution of respiratory airflow was determined in 120 'mouth breathing' children by a minimally invasive computer-assisted method that employed a modified CPAP nasal mask/pneumotach and a head-out body plethysmograph. Resulting measurements were reproducible but clinical assessments correlated poorly with these values. Airflow distribution was almost identical in inspiration and expiration. 100% nasal breathing was found over a wide range of nasal resistances, many subjects with lips apart. Overall, the nasal fraction was negatively correlated with resistance and it was increased by topical decongestant. Decreasing nasal resistance with increasing age was confirmed, but corresponding changes in airflow distribution were not demonstrated. Quantitative assessment is advocated in clinical management of 'mouth breathers'.     

Nature and significance of endoleaks and endotension: summary of opinions expressed at an international conference

OBJECTIVE: Endoleaks and endotension are critically important complications of some endovascular aortic aneurysm repairs (EVARs). For the resolution of controversial issues and the determination of areas of uncertainty relating to these complications, a conference of 27 interested leaders was held on November 20, 2000. METHODS: These 27 participants (21 vascular surgeons, five interventional radiologists, one cardiologist) had previously answered 40 key questions on endoleaks and endotension. At the conference, these 40 questions and participant answers were discussed and in some cases modified to determine points of agreement (consensus), near consensus (prevailing opinion), or disagreement. RESULTS: Conference discussion added two modified questions for a total of 42 key questions for the participants. Interestingly, consensus was reached on the answers to 24 of 42 or 57% of the questions, and near consensus was reached on 14 of 42 or 33% of the questions. Only with the answers to four of 42 or 10% of the questions was there persistent controversy or disagreement. CONCLUSION: The current endoleak classification system with some important modifications is adequate. Types I and II endoleak occur after 0 to 10% and 10% to 25% of EVARs, respectively. Many (30% to 100%) type II endoleaks will seal and have no detrimental effect, which never or rarely occurs with type I endoleaks. Not all endoleaks can be visualized with any technique, and increased pressure (endotension) can be transmitted through clot. Aneurysm pulsatility after EVAR correlates poorly with endoleaks and endotension. An enlarging aneurysm after EVAR mandates surgical or interventional treatment. These and other conclusions will help to resolve controversy and aid in the management of these vexing complications and should also point the way to future research in this field.     

Arrangement of orientation pinwheel centers around area 17/18 transition zone in cat visual cortex

In the primary visual cortex of higher mammals, orientation preferences are represented continuously except for singular points, so-called pinwheel centers. In spite of the uniqueness of orientation pinwheel centers, very little is known about the pattern of their arrangement. In this study we examined the arrangement of orientation pinwheel centers in the cat visual cortex by optical imaging of intrinsic signals. Our results demonstrate that orientation pinwheel centers are arranged in a unique geometric pattern around the area 17/18 transition zone: pinwheel centers of the same type are arranged in rows parallel to the transition zone, and rows of clockwise and counterclockwise pinwheel centers are arranged alternately. We suggest that the areal border imposes a strong restriction on the pattern formation of orientation preference maps in the visual cortex.     

The effect of sedation with propofol and fentanyl during epidural catheter insertion on intraoperative temperatures

General anesthesia inhibits thermoregulation by suppressing tonic vasoconstriction and facilitates a core-to-peripheral redistribution of body heat, which is the major cause of core hypothermia during the first hour of anesthesia. We randomly assigned 16 patients to two groups; 1) patients who received fentanyl (1 microgram.kg-1, i.v.) and propofol (1.5 mg.kg-1.h-1) during insertion of epidural catheters (P group), and 2) no drug (control) group (C group). We measured tympanic (Ttym) and skin temperatures at the time of admission to operating rooms, after dural catheter insertion, before induction of anesthesia, just after induction of anesthesia, and one hour after induction. After dural catheter insertion, forearm-finger tip skin temperature gradient of P group was significantly smaller than C group. One hour after induction of anesthesia, Ttym of P group was significantly higher than C group. We can conclude that a sedative dose of propofol and fentanyl before induction of general anesthesia inhibits redistribution hypothermia during general anesthesia.