Superficial- and deep-tissue temperature increases in anesthetized dogs during exposure to high specific absorption rates in a 1.5-T MR imager

Superficial- and deep-tissue heating was measured in five dogs during high-specific-absorption-rate radiofrequency (RF) irradiation to see whether significant temperature changes could be produced by a 1.5-T clinical magnetic resonance imager. The RF power output employed was 6.3 times that required for routine imaging. Temperature probes were placed in both deep and superficial tissues, and temperatures were recorded before, during, and after exposure. In each dog, there was a linear temperature increase of several degrees during RF exposure; the maximal average change was 4.6 degrees C in the urinary bladder. The temperature increase was slightly greater in deep tissues than in superficial tissues. The calculated specific absorption rate, based on the temperature change, averaged 7.9 W/kg for all five dogs. These findings argue for continued caution in the design and operation of imagers capable of high specific absorption rates, particularly when they are used for imaging infants or patients with altered thermoregulatory capability.     

Computed tomographic angiography of the body

Large and medium-sized blood vessels can be identified on extracranial computed tomographic (CT) scans when a combination of infusion and bolus injection of conventional contrast material is administered. The cases illustrated in this report show that CT angiography can sometimes offer clinically useful information not present on CT scans obtained without contrast injection.     

Psychological Correlates of Outcome after Coronary Artery Bypass Graft

Background

Psychological effects of Coronary Artery Bypass graft (CABG) have been of interest all over the world but there is a paucity of Indian work.

Methods

30 patients undergoing CABG at a service hospital were included. All patients filled a specially designed proforma. Mini Mental Status Examination, Hospital anxiety and depression scale, Coronary scale, Seattle angina questionnaire and Euro-QOL 5D were performed before and seven days after CABG.

Results

43.3% had significant anxiety and 30% had significant depression before CABG. Following CABG, 36.67% of the patients had significant anxiety while 40% had significant depression. On the Seattle angina questionnaire, physical limitation reduced from 71.6 ± 7.9 to 53.1 ± 14.6. There was significant improvement in treatment satisfaction from 37.8 ± 6.1 to 59.4 ± 4.2 following CABG. On th euro quality of life scale (EQ5D) health status improved from 38.17 ± 9.51 before CABG to 68.5 ± 5.28 after CABG.

Conclusion

There is a significant incidence of anxiety and depression in patients undergoing CABG, both before and after surgery.Key Words: CABG, anxiety, depression     

Characteristics of Rabbit Food-Procuring Behavior as an Indicator of Changes in the Level of Hunger Motivation

We proposed new method for measuring dynamic changes in hunger motivation in rabbits in the course of satisfaction of nutritional need by weight, time, and rate parameters of effective food-procuring behavior. Transformation of the amount of food eaten into the electric signals was performed using electronic weighing machine incorporated into hardware and software system. The most conclusive characteristic for decrease in hunger motivation in the course of first effective food-procuring act was the period of food-procuring cycles, which values increase signifi cantly as animal satisfi es its nutritional need, whereas amount of the food consumed for each food-procuring cycle remains constant. Integral characteristics of food-procuring behavior reflect higher level of food motivation in the course of first effective food-procuring act in comparison to the subsequent ones.