How Topographic Diffusion-Weighted Imaging Patterns can Predict the Potential Embolic Source

PURPOSE

To develop an imaging prediction model for patients with embolic stroke of undetermined source (ESUS), we investigated the association of topographic diffusion-weighted imaging (DWI) patterns with potential embolic sources (PES) identified by transesophageal echocardiography.

METHODS

From a total of 992 consecutive patients with embolic stroke, 366 patients with the ESUS group were selected. ESUS was defined as no atrial fibrillation (Af) within 24h from admission and no PES after general examination. Clinical variables include age (> 80years, 70-80 years), sex, vascular risk factors and left atrial diameter > 4 cm. Age, sex and vascular risk factors adjusted odds ratio of each DWI for the different PESs were calculated. DWI was determined based on the arterial territories. Middle cerebral arteries were divided into 4 segments, i.e., M1-M4. Moreover, M2 segments were subdivided into superior and inferior branches.

RESULTS

The 366 patients consisted of 168 with paroxysmal Af (pAf), 77 with paradoxical embolism, 71 with aortic embolism and 50 with undetermined embolism after transesophageal echocardiography. The variables adjusted odds ratio (OR) of internal carotid artery (OR: 12.1, p = 0.037), M1 (4.2, p = 0.001), inferior M2 (7.5, p = 0.0041) and multiple cortical branches (12.6, p < 0.0001) were significantly higher in patients with pAf. Striatocapsular infarction (12.5, p < 0.0001) and posterior inferior cerebellar artery infarcts (3.6, p = 0.018) were significantly associated with paradoxical embolism. Clinical variables adjusted OR of multiple small scattered infarcts (8.3, p < 0.0001) were significantly higher in patients with aortic embolism.

CONCLUSION

The associations of DWI with different PES have their distinctive characteristics and DWI along with clinical variables may help predict PES in patients with ESUS.

[Work intensity during working hours and different types of care done by special nursing home workers]

This study was done to estimated work intensity during working hours and different types of care to obtain basic data for making a care program. The subjects were care workers in good health (n = 8, 24-45 years) who worked in a special nursing home. The estimated maximal oxygen intake level, which is the maximal aerobic capacity, of each subject was assessed as normal to very good. The energy expenditure was 1787 +/- 534kcal during working hours. The work intensity was 0.061 +/- 0.011kcal/kg/min, 2.7 +/- 0.7RMR, 98 +/- 6beats/min, and 30.3 +/- 2.0% VO2max. Among the duties assessed for work intensity, bathing had the highest intensity, followed by transferring, changing diapers, feeding, and dressing. The work intensity of bathing was 0.081 +/- 0.31kcal/kg/min, 3.9 +/- 1.0RMR, and 40.0 +/- 6.1 VO2 max, which was significantly higher than feeding, dressing, and transferring(p < 0.05). Care giving at the time of bathing was significantly longer than the other care types (p < 0.05). Feeding and transferring by inexperienced care workers were significantly low intensity (p < 0.05). Work intensity of care was at high levels within the maximal permissible level in which fatigue doesn't make an appearance during working hours and in five types of care. Furthermore, care work intensity increased according to a decrease in the ADL level among the elderly. It is concluded that when making a care program, it is important to consider the ADL level of the elderly, work intensity and the amount of care-giving time, not only to maintain the health of care workers, but, also, to give superior quality care to the elderly.