AUTONOMIC DISORDERS:

Evaluation of the finger wrinkling test: a pilot study

Purpose

Tilt table testing mainly evaluates the systemic cardiovascular part of the autonomic nervous system, while it is assumed that the finger wrinkling test assesses the peripheral part of the autonomic nervous system. In this study we explored whether the finger wrinkling test could be a useful test for autonomic dysfunction and whether the clinical evaluation of wrinkling can be improved by digital analysis of photographs.

Methods

As much as 20 healthy subjects and 15 patients underwent tilt table testing and finger wrinkling testing. During the finger wrinkling test the right hand was immersed in water at 40°C. The degree of wrinkling was assessed with a 5-point clinical scale at baseline, 5, 15 and 30 min of immersion. Photographs were taken at the same intervals. Several features were evaluated using digital analysis: length and gradient of automatically detected wrinkle and mean, maximum, minimum, variance and derivative of grey value of pixels.

Results

Clinical scoring of wrinkling allowed differentiation between healthy subjects and patients with a normal and an abnormal response to tilt table testing. Relevant features obtained with digital analysis were mean grey value and the gradient of automatically detected wrinkle. McNemar’s test showed no difference in test results between the tilt table test and the finger wrinkling test with a kappa of 0.68.

Conclusion

The finger wrinkling test can be used as a screening test before tilt table testing. Visual evaluation of wrinkling is still superior to digital analysis of photographs.

Probabilistic assessment of Autonomic Nervous System fluctuations during tilt table tests

A number of reports have advocated the use of Heart Rate Variability (HRV) as a non invasive method of monitoring the Autonomic Nervous System (ANS). In the anesthesia and critical care monitoring settings, the development of an instrument able to provide real-time information about the ANS state at different stages of any procedure would provide improved safety for patients undergoing diagnostic or therapeutic interventions. However, real-time analysis of HRV can be particularly challenging since larger effective lengths of observation provide better spectral resolution. Our study explores a probabilistic approach that analyzes changes in HRV parameters obtained from an autoregressive (AR) model technique using Burg's methods to evaluate very short observation windows while preserving appropriate frequency resolution. These HRV parameters are continuosly compared to a baseline state, and a probability trend is updated during provocative maneuvers. Preliminary results show that trends from classical parameters such as RMSSD and LFn are consistent and reliable instruments capable of providing significant information about ANS fluctuations in a timely fashion.

Dysautonomia rhinitis: associated otolaryngologic manifestations and characterization based on autonomic function tests

CONCLUSIONS

Dysautonomia is a multisystem disorder. Beside the nasal symptoms, some otolaryngological disorders may be explained on the basis of autonomic dysfunction. Testing of the autonomic nervous system (ANS) complements the clinical findings and provides objective measurements to substantiate the presence of ANS dysfunction. The term dysautonomia rhinitis may be used to specify this autonomic-related rhinitis.

OBJECTIVES

Nonallergic, noninfectious perennial rhinitis is a heterogeneous disorder comprising several pathophysiological entities. This study was designed to objectively investigate the relation of idiopathic perennial rhinitis to ANS dysfunction.

PATIENTS AND METHODS

This was a prospective controlled clinical study; 78 patients, carefully diagnosed as having idiopathic perennial rhinitis, were enrolled. Workshop protocol included diagnostic measures for exclusion of other causes of rhinitis and autonomic function assessment at a clinical cardiology laboratory. Results were compared with those of 20 age- and sex-matched normal control subjects.

RESULTS

In addition to their nasal symptoms, all patients reported more than one regional and multisystem complaint. Each patient had at least one autonomic function test that displayed a hypervagal response and the overall response score was as follows: 46 (59%) had hypervagal response, 32 (41%) had mixed response and none had a normal or hyperadrenergic response.