F-4-02-03
Muscle Sympathetic Nerve Activity during Cold Pressor Test in CVA Patients.
Takashi Mizushima, H. Ogata, F. Tajima, and T. Nakamura.
(University of Occupational and Environmental Health, Kitakyushu, Japan)
Disturbance of autonomic functions are frequently encountered in cerebrovascular attack (CVA) patients. However their pathophysiological mechanisms are unclear. The purpose of the study was to assess quantitatively the effects of cerebrovasucular attack on autonomic nervous system. We analyzed muscle sympathetic nerve activity (MSNA) from the peroneal nerve of hemiplegic side in using the technique of microneurography during 3 min ice water immersion of non-hemiplegic hand in 9 age- matched healthy control subjects and in 10 chronic CVA patients who had damage of the cortical or subcortical structures. Similarly, heart rate, arterial pressure, hand temperature and perception of pain were recorded. Total MSNA in CVA patients and control subjects during control period significantly increased during immersion period. However, interestingly, the rate of increase of MSNA in CVA subjects during immersion was attenuated being compared with control subjects. Other measurements in CVA patients were consistent with control subjects. This study demonstrated that the percent change of total MSNA (MSNA response) during ice water immersion tended to be attenuated in CVA patients compared with healthy control. This behavior of MSNA observed in the CVA subjects may result from their lesion or the damage of neural pathways known to regulate the autonomic system above vasomotor area in the medulla. The present results concluded that central command above vasomotor area in the medulla might exert a significant modularly influence on sympathetic nervous system in humans.
F-4-02-04
THERMOGRAPHIC PARAMETERS IN THE DIAGNOSIS OF RAYNAUD'S SYNDROME
O. Schuhfried, G. Vacariu, M. Korpan, T. Lang, W. Graninger. V.Fialka (University of Vienna, Austria)
PURPOSE: The aim of the study was to determine the sensitivity of thermographic parameters in discriminating between patients with Raynaud's Phenomenon of different severity.
METHOD: By means of clinical assessment and infrared thermography before and after a standardized cold water test (16℃, 1 min) 86 patients were investigated for Raynaud's Phenomenon. According to colour changes induced by cold exposure (triphasic, biphasic, monophasic) as the major criterion and underlying disease and immunological findings (ANA) as minor criteria clinical grading was performed as follows: no Raynaud's Phenomenon=0, unlikely=1, probable=2, definite Raynaud's Phenomenon=3. The following thermographic parameters were applied to a stepwise logistic regression analysis: absolute temperature of fingertips before, 10 and 20 minutes after cold challenge (Tpre, T10, T20); longitudinal temperature difference before, 10 and 20 minutes after cold challenge (LTDpre, LTD10, LTD20); recovery index 20 minutes after cold challenge (RI20); mean area under the curve (MAUC); rapid phase of rewarming of both hands (Gmax). The sensitivity of classification into the 4 groups was assessed by discriminant analysis.
RESULTS: Only LTDpre fulfilled the level of significance (p<0.05). Although thermographical classification was possible for patients of group 0 and 3, in patients of group 1 and 2 the diagnosis of equivocal Raynaud's Phenomenon was not confirmed thermographically.
CONCLUSION: LTDpre is the major parameter to identify patients with definite Raynaud's Phenomenon and without Raynaud's Phenomenon. For patients with uncertain clinical symptoms additional investigations are necessary.
