Skin Reflex Research Articles

Characteristics of autonomic neuropathy in patients with vestibular migraine

Objective: To investigate the characteristics of autonomic neuropathy in patients with vestibular migraine (VM) by sympathetic skin reflex (SSR) and R-R interval variation (RRIV). Methods: Seventy-three patients with interseizure VM and 36 healthy controls in the Department of Neurology affiliated to Shanghai Fourth People's Hospital of Tongji University from November 1, 2019 to December 31, 2021 were prospectively enrolled. SSR and RRIV were performed and relevant parameters were recorded, including SSR latency, SSR amplitude, RRIV during calm breathing (R%), RRIV during deep breathing (D%), RRIV difference between deep breathing and calm breathing (D%-R%), RRIV ratio between deep breathing and calm breathing (D%/R%), and the difference and correlation of various parameters between VM patients and healthy controls were analyzed. Results: Among the 73 patients with VM, there were 12 males and 61 females, and aged (46±13) years. While among 36 healthy controls, there were 6 males and 30 females, and aged (46±7) years. Among the 73 VM patients, abnormal SSR, abnormal RRIV, abnormal SSR and RRIV, and abnormal SSR or RRIV was detected in 38 cases (52%), 17 cases (23%), 11 cases (15%) and 44 cases (60%), respectively. Compared with healthy controls, the lower extremity SSR latency [(1 719±289) ms] in VM patients was longer than that in control group [(1 500±349) ms] (P=0.001), but the upper extremity SSR amplitude [1.6 (0.8, 3.0) mV] was lower than that in control group [2.6 (1.8, 4.2) mV] (P=0.006). SSR amplitude, R% and D% were negatively correlated with age in VM patients (rs=-0.311, P=0.007; rs=-0.237, P=0.043; rs=-0.263, P=0.024, respectively). SSR of lower extremity in VM patients was longer than that of upper extremity [(1 719±289) ms vs (1 244±185) ms, P<0.001], but the amplitude of lower extremity was lower than that of upper extremity [0.8 (0.3, 1.7) mV vs 1.6 (0.8, 3.0) mV, P<0.001]. SSR latency of upper limb was positively correlated with SSR latency of lower limb (r=0.436, P<0.001), the amplitude of upper limb was positively correlated with amplitude of lower limb (rs=0.456, P<0.001), and D% was positively correlated with R% (rs=0.357, P=0.002). Conclusion: The autonomic neuropathy during VM interphase features with imbalance between sympathetic and parasympathetic nervous system, and the sympathetic nerve function is mainly impaired.

А. F. Samoilov at scientific meetings of the Kazan Clinical Institute in 1921-1924

Since 1921, at the monthly scientific meetings of the Kazan Clinical Institute, opened in 1920, later renamed the Kazan Institute for the Improvement of Physicians, GIDUV, the head of the Department of Physiology of the Faculty of Physics and Mathematics of Kazan University, a world-famous physiologist, made presentations and debates more than once, one of the creators of the theory of electrocardiography and neuromuscular transmission, Professor A. F. Samoilov. A scientist with an encyclopedic education, he generously shared his knowledge with an audience of doctors, took an active part in the development of the scientific life of the Kazan Clinical Institute. His reports at scientific meetings familiarized physicians with the results of the experimental work of the physiological laboratory of A. F. Samoilov at Kazan University, with the works and scientific position of famous physiologists. Scientific meetings, speeches and the presence of prominent scientists of Kazan, rich in form and content of discussions of reports, scientific discussions have become a school of creative thinking for the young generation of doctors and scientists of the Kazan Clinical Institute — GIDUV. The article for the first time presents materials about these speeches by A. F. Samoilov about G. Helmholtz, J. Loeb, recordings of heart sounds, about the galvanic skin reflex, about setting up a scientific and educational process at universities in the USA and Europe.

M. Bertolotti About cross skin reflexes. And propos des reflexes cutanes croises. - Revue neurol, 1909, № 2

In the author's opinion, skin reflexes are generally of little importance for the semiotics of nervous diseases.&#x0D; The cross-skin reflexes studied by Kluppel and Weil are also not worthy of deep study. They serve only as an indicator of the large spread of the reflexogenic area and correspond to long-established physiological laws, according to which skin reflexes are considered as a protective act.

The Value of Sacral Reflex and Sympathetic Skin Reflex in the Diagnosis of Multiple System Atrophy P-Type.

Objectives To observe the characteristics of sacral reflex and sympathetic skin reflex in patients with Parkinson's disease (PD) and multiple system atrophy P-type (MSA-P) and to analyze their value as a differential diagnostic method. Methods The data of 30 healthy people, 58 PD patients, and 52 MSA-P patients from the First Affiliated Hospital of Wenzhou Medical University were collected. Electrophysiological bulbocavernosus reflex (BCR) and sympathetic skin response (SSR) were evaluated using the Keypoint EMG/EP system. The latency period, amplitude, and extraction rate of BCR and SSR were compared between the control, PD, and MSA-P groups. Results The incidence of the related autonomic damage in the PD group was lower than that of the MSA-P group. For BCR, the latency period was shorter and the amplitude and elicitation rates were lower in the PD group than in the MSA-P group. For SSR, the latency period was longer in the MSA-P and PD groups than in the control group, but the difference was not statistically significant. Conclusion SSR cannot be used to assess autonomic nerve function. PD patients can have clinical symptoms similar to those of MSA-P patients, but the incidence is lower. Both MSA-P and PD patients have a damage to the BCR arc, but the MSA-P patients have a more severe damage.

Clinical case of Parry–Romberg syndrome

PParry–Romberg syndrome, also known as progressive hemifacial atrophy, is a rare clinical entity of unknown origin with atrophy of skin and subcutaneous fat changes. A classic case of Parry–Romberg syndrome in a woman age 43 is presented. Initial facial changes appeared at the age of 20 years amid complete well-being and in the next 21 years a subcutaneous fat atrophy of the left half face developed, resulting in characteristic deformity changes. No other complaints and manifestations of the disease (epileptic seizures, headache, involvement of the other half of the face and/or extremities) were present at the timeof survey. The analysis of blink reflex, galvanic skin reflex, needle electromyography of the m. orbicularis oris from two sides, computed tomography of the skull bones revealed no pathological changes. The face infrared thermography confirmed asymmetric reduction of temperature on the ipsilateral side. Magnetic resonance scan showed hypotrophy of the left masticatory muscle, the left submandibular salivary gland, thinning of subcutaneous fat layer, changes in the white matter of the brain. Despite the typical clinical features the Parry - Romberg syndrome is a diagnostic challenge known and it is necessary to inform doctors about the latest achievements in the study of etiology, management and prognosis of the disorder.

How to explore automic dysfunction on clinical practice?

Objectives Various validated clinical scales and questionnaires are available and many neurophysiological and functional tests have been developed to evaluate dysautonomia. This work aims to review the neurophysiological tools that can be used to characterize distal autonomic dysfunction, particularly in the context of peripheral neuropathies. Methods Neurophysiological tests exploring autonomic vasomotor and sudomotor function have been reviewed. The accuracy of each technique for the diagnosis of small-fiber autonomic neuropathy has been assessed. Results Sudomotor innervation can be investigated by many tests including sympathetic skin reflex recording (SSR), quantitative sudomotor axon reflex testing (QSART), electrochemical skin conductance measurement (ESC) by Sudoscan®, and the Neuropad® colorimetric test. Both the Neuropad® test and ESC measurement by Sudoscan®, provide early markers of neuropathy in context of familial amyloid polyneuropathy as well as in diabetic polyneuropathy. The Neuropad® test could be used as a screening tool, requiring confirmation by ESC measurement by Sudoscan®, which is more convenient for follow-up assessment. Unlike the SSR, QSART is also a sensitive test for detecting sudomotor dysfunction. However, its test-retest reliability is really moderate. For vasomotor aspects, investigation includes the stimulated skin wrinkling (SSW) test, laser Doppler flowmetry (LDF) and laser Doppler imaging (LDI-flare). The SSW test appears valuable when applied to the fingers, but not to the toes. The LDF and LDI-flare tests were found to be sensitive in various clinical contexts (e.g., Parkinson's disease, diabetes, and HIV infection), but they lack standardization and have poor test-retest reliability, especially LDF. Conclusion Sudomotor tests and notably ESC measurement by Sudoscan® appear to be relevant to assess distal autonomic dysfunction in the context of peripheral neuropathy, while the reliability of vasomotor tests should still be improved. Finally, various autonomic tests that are not performed at limb extremities can also be very informative and sensitive in this clinical context, such as heart rate variability measurement at deep breathing.

A reappraisal of small- and large-fiber damage in carpal tunnel syndrome: New insights into the value of the EMLA test for improving diagnostic sensitivity

To reappraise the respective involvement of small- and large-fiber damage in carpal tunnel syndrome (CTS) and to determine the diagnostic sensitivity of autonomic tests compared to conventional nerve conduction study (NCS). Thirty-two manual workers complaining of at least unilateral CTS were enrolled. They underwent clinical interview and completed the symptom severity scale of the Boston CTS Questionnaire (sssBCTQ) and the Neuropathic Pain Symptom Inventory (NPSI). In addition, transcarpal NCS was performed to investigate large sensory and motor fibers of the median nerve, while small autonomic fibers were assessed by recording sympathetic skin reflexes (SSR) at the palm and by grading skin wrinkling in response to eutectic mixture of local anesthetic (EMLA) cream application at the pulp of the index finger. For each neurophysiological variable, sensitivity and specificity values for the diagnosis of CTS were calculated and clinical correlations were studied. Among 64 hands examined, 36 were clinically symptomatic, while 22 were clinically asymptomatic and served as controls. Among all the neurophysiological variables studied, only the values of transcarpal sensory nerve conduction velocity and the EMLA test grade were found to be more altered in clinically symptomatic hands, with also a trend towards prolonged distal motor latency. Overall, for the diagnosis of clinically symptomatic CTS, NCS, SSR, and the EMLA test had a sensitivity of 66.7%, 22.2%, and 69.4%, respectively, and a specificity of 72.7%, 90.9%, and 50%, respectively. Combining NCS and the EMLA test led to a sensitivity of 88.9% and a specificity of 45.4%. The sssBCTQ (r=-0.34, P=0.009) and the total NPSI score (r=-0.41, P=0.001) correlated to a more altered EMLA test grade, but not to any NCS or SSR variables. In symptomatic hands, burning sensation was associated with more severe small-fiber lesion, while other pain and sensory symptoms were rather found to be reduced in case of large-fiber damage, evidenced by NCS alteration. This study confirms the discrepancy between conventional NCS results and clinical presentation of CTS, but still suggests a major involvement of Aβ fibers in the positive sensory symptoms of CTS, excepting burning sensation. On the other hand, the EMLA test was found to correlate with clinical data and to be able to improve sensitivity of neurophysiological investigation in diagnosing CTS.

63. Guillain-Barrè syndrome with marked pleocytosis in the cerebrospinal fluid: A case report

A 71 years old female patient referred to her Physician for left hip and abdominal, nigh-time worsening pain. For this reason, she underwent a lumbosacral vertebral MRI, that highlighted the presence of L3-S1 left radiculopathy. After two weeks, she developed a left VI and VII cranial (peripheral) nerves palsy. Admitted to hospital, she underwent brain CT and MRI, that resulted unremarkable. In Neurology division, on examination a left VI cranial nerve palsy, a bilateral VII cranial nerve palsy, dysarthria, dysphagia and increased tendon reflexes were observed. The neurophysiology investigation revealed diffuse delayed F-waves with axonal response, absent H reflex, asymmetrical skin reflex, normal distal M-waves latencies, central and peripheral motor and sensitive conduction, and EEG. In light of these findings, matching the hypothesis of acute polyradiculoneuritis a lumbar puncture was performed. Increased CSF proteins and white cell count were found, while microbiological exams were unremarkable. A combination iv treatment (ceftriaxon, acyclovir, human IG) was established. Because of the onset of tetraparesis and respiratory failure, the patient was admitted to the intensive care unit. Even if case of CSF pleocytosis (>50/ μ l) a differential diagnosis should be considered 1–2 this case report suggests that Guillain-Barre diagnosis can not defectively ruled out.

Sympathetic skin response in acute ischemic stroke - Hemispheric asymmetry

Modern knowledge indicates greater scope and complexity of autonomic dysfunction after acute stroke. In addition to cardiovascular and respiratory disorders there are disturbances in sweat regulation and the responses of the sympathetic skin reflex in cerebrovascular disease. Bilateral changes in the parameters of the sympathetic skin response, as a result of unilateral cortical lesions are associated with the influence of inhibitory or stimulatory effects of the cerebral cortex and the reticular formation, which have a complex association with the contralateral cortical structures of the sympathetic system. The results of our study of patients with acute hemispheric ischemic stroke showed significant difference in the amplitude and latency between the affected and unaffected limbs, only in the group of patients with ischemic stroke in the territory of the right middle cerebral artery with involvement of the insular cortex. When we compared our results from patients with stroke in the left hemisphere with those with stroke the in right hemisphere, we established longer latency times and lower amplitudes in patients with right hemispheric strokes, The most marked ones are the abnormal values in patients with ischemic stroke in the territory of the right middle cerebral artery with involvement of the insular cortex .

Could autonomic system assessment be helpful in disorders of consciousness diagnosis? A neurophysiological study

Although patients with chronic disorders of consciousness (DOC), including unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), show a limited repertoire of awareness signs, owing to a large-scale cortico-thalamo-cortical functional disconnectivity, an activation of some cortical areas in response to relevant stimuli has been described by means of electrophysiological and functional neuroimaging approaches. In addition, cognitive processes associated with autonomic nervous system (ANS) responses elicited by nociceptive stimuli have been identified in some DOC patients. In an attempt to identify ANS functionality markers that could be useful in differentiating UWS and MCS individuals, we measured the amplitude, latency and γ-band power (γPOW) of ultra-late laser-evoked potentials (CLEPs) and skin reflex (SR), which both express some aspects of cognitive processes related to ANS functionality, besides other ANS parameters either during a 24(hh)-polygraphy or following a solid-state laser repetitive nociceptive stimulation. MCS showed physiological modification of vital signs (O2 saturation, hearth rate, hearth rate variability) throughout the night and a preservation of SR-γPOW, whereas UWS did not show significant variations. Following repetitive nociceptive stimulation, MCS patients had a significant increase in CLEP-γPOW, O2 saturation, hearth rate, and hearth rate variability, whereas UWS individuals did not show any significant change (but two patients, who reached high Coma Recovery Scale-Revised scores). Hence, our work suggests that a wide-spectrum electrophysiological evaluation of ANS functionality may support DOC differential diagnosis. Interestingly, the two above-mentioned UWS patients showed MCS-like vital sign modifications and electrophysiological pain responsiveness. It is therefore hypothesizable that our approach could be helpful in identifying residual aware autonomic system-related cognitive processes even in some UWS patients. Such issue draws the attention to either DOC clinical diagnosis or adequate pain treatment in DOC patients.

33. A rare case of Guillain–Barre’ syndrome and pseudotumor cerebri, with normal cerebrospinal fluid protein

A 19 years old female patient was referred for assessment of head and cervical pain, upper limbs dysesthesias, diplopia, visual impairment (mainly in left eye) and postural instability. Initial examination revealed left ptosis, left abducent nerve palsy, diffuse hyporeflexia and limb ataxia. At admission lumbar puncture was performed with a normal cerebrospinal fluid analysis and a temporal dispersion of F waves and Skin Reflex was observed by electromyography. In suspicion of a Guillain–Barre syndrome a IV immunoglobulin treatment was administered. In first days after admission a progression of sings and symptoms was observed; a left peripheral facial palsy was also noted. In particular, the visual acuity decreased in both eyes (5/10 at right, 1–2/10 at left), severe bilateral papilledema and increased optic nerves diameters (7.4 mm at left) were revealed. Brain and spine MRI was unremarkable. Thus, through a second lumbar puncture a cerebrospinal fluid pressure of 25 mmHg was measured. In light of this 10 cc of cerebrospinal fluid were subtracted and high dosage escalating diuretic treatment (mannitol, steroid, acetazolamide and topiramate) was administrated. A further slow improvement of motor and visual signs and symptoms was observed. At discharge the patient referred a complete remission of headache and dysesthesias.

The significance of psychiatric disorders in criminal conduct

Abstract: Analysis of convicts’ cerebral (neuropsychiatric) pathology in order to optimize their resocialization, improve social adaptation, quality of life and achieve goals of criminal punishment in the sphere of prevention of criminal behavior. Material and methods . 250 men aged between 35 and 50 years were examined. The first survey sample consisted of convicted (n = 50). They committed robbery, brigandage, rape, disorderly conduct, inflicted bodily injury (age — 43.6 ± 2.6 years). These crimes imply violence against the victim. The second (control) survey sample included those (n = 200) who had no previous convictions (age — 42.4 ± 2.8 years). The sampling is ran-dom and representative. Clinical examination (research), as well as electroencephalography, electrocardiography, galvanic skin reflex, psychological research (Minnesota Multiphasic Personality Inventory (MMPI), the Spilberger test (STAI)) and other brain studies was carried out. Result and conclusion . The neurotic complaints were more frequent among convicts. Neurological symptoms of brain lesions were more frequent among the convicts. The dif -ference between the first and the second survey sample was statistically significant. The majority of surveyed convicts had thought disorders. They poorly predicted consequences of their actions. Cerebral pathology impairs the ability to perceive universal human values, rules of society. Peculiarities of such person’s cerebral pathology are reduced to an inability to exercise control over the lawful behavior. A person with cerebral disorders is more prone to criminal behavior. We discuss the possibility of criminals’ resocialization by means of treating cerebral disorders. Convicted need cerebral metabolism restoration therapy. This will improve axonal communication and structural and functional neuronal activity. Ethiopatogenetic therapy of cerebral disorders contributes to the re-socialization of convicts, im-provement of social adaptation, quality of life, crime prevention. The study complements clinical criminology theory.

P141. Neuralgic amyotrophy associated with Hepatitis E infection – A case report

Introduction The cause of neuralgic amyotrophy (NA; Parsonage–Turner syndrome) remains unknown, but different infections often precede NA, and an idiopathic autoimmune response generating nerve inflammation has been postulated. Hepatitis E virus (HEV) infections are endemic in developing countries (genotypes 1 & 2). Within the last years, an increasing number of locally acquired HEV infections have been described in western countries (genotypes 3& 4). We present here the case of a previously healthy 37years old male with NA associated to autochthonous HEV infection, presumably caused by a meal of raw pork one week before symptom onset. Case report Admission was due to bilateral arm and upper spine pain with paraesthesia of both upper extremities. Previous orthopaedic presentation ruled out vertebral disk herniation, myelopathy and foraminal stenosis by Magnetic Resonance (MR) Imaging. Neurological examination revealed right-sided scapula alata and palsies of arm abduction, elbow flexion/extension, thumb opposition and finger splaying. Numbness was present on the radial side of both forearms. Right-sided biceps and triceps reflexes were reduced; Tromner's reflex was absent. Sensible and motoric nerve conduction velocity (NCV) of the median and radial nerve, F-wave examinations, sympathic skin reflex (SSR) and electromyography (EMG; anterior serratus and deltoid muscle) were normal. Liver enzymes were elevated: AST 325 U/L, ALT 1774 U/L, AP 304 U/L, GGT 205 U/L. Cerebral spinal fluid (CSF) revealed lymphomonocytic pleocytosis (14cells/μl), signs of blood–brain–barrier disruption and elevated protein (77.6mg/dl) with normal lactate and glucose levels. CSF HEV-, HSV-, VZV-PCR and Borellia IgM were negative. Further tests ruled out Treponema pallidum, Rubella, Rubeola, Mumps, TBE (tick borne encephalitis), Hepatitis A,B,C, HIV, CMV and EBV. Serum-HEV-RNA was positive (8.3×10 4 cop/ml; genotype 3c). Assuming HEV-associated NA, oral administration of methylprednisolone was started (80mg, tapering thereafter), and patient's pain remarkably decreased. High resolution magnetic resonance neurography (3Tesla) after two months revealed fascicular T2 hyperintense lesions of the ulnar, radial and median nerves and brachial and triceps muscle denervation. Clinical follow-up examination showed typical findings of a Parsonage–Turner syndrome with atrophy of the right upper arm muscles, (improved) scapula alata and palsies of elbow flexion, thumb opposition, flexion and finger splaying. Bilateral hypaesthesia on radial side of forearms persisted. Arm abduction and elbow extension improved. NCV, SSR and F-wave were again normal. However, EMG (abductor digiti minimi, flexor pollicis longus, flexor digitorum superficialis muscles) now discovered denervation. Conclusions NA is rare and association with Hepatitis E infections have been described in single patients. While diagnosis can be difficult, clinicians should consider this sporadic entity, particularly when typical neurologic signs are combined with elevated liver enzymes.

Joseph Babinski's contribution to neurological symptomatology

Joseph Babinski (1857-1932) was an excellent clinician. André Breton, a French poet, described Babinski's way of clinical examination in his Manifeste du surréalisme (1924), which vividly revealed Babinski's meticulous character. Babinski is well known by his eponymous Babinski reflex. Although some predecessors had described this phenomenon briefly, its meaning was interpreted by Babinski. His contribution to neurological symptomatology was not restricted to his plantar skin reflex, but also to other wide area. In this article, symptoms described by Babinski, i.e. plantar skin reflex, cerebellar symptoms including cerebellar asynergy, adiadochokinesis, dysmetria, cerebellar catalepsy, and rising sign, platysma sign, anosognosia are explained and are critically discussed.

Sjögren Syndrome-Associated Small Fiber Neuropathy

We conducted the current study to analyze the clinical, immunologic, and neurophysiologic features of primary Sjögren syndrome (pSS)-associated sensory small fiber neuropathies (SFNs). Forty consecutive pSS patients with SFN were included. SFN was defined by the presence of suggestive sensory painful symptoms with normal nerve conduction studies and abnormal neurophysiologic tests for small nerve fibers or a low intraepidermal nerve fiber density at skin biopsy. Included patients were compared to 100 pSS patients without peripheral neuropathy.SFN patients were mainly female (92.5%). Age at pSS diagnosis was 55.3 ± 13.1 years, and at SFN diagnosis, 58.9 ± 11.8 years, with a median time to SFN diagnosis after symptom onset of 3.4 years. Clinical symptoms included burning pains (90%), numbness (87.5%), tingling (82.5%), pins and needles (72.5%), electric discharges (70%), and allodynia (55%). Dysautonomia included vasomotor symptoms (66%) and hyperhidrosis (47%). Abnormal neurophysiologic tests included laser evoked potentials (97.5%), thermal quantitative sensory testing (67.5%), and sympathetic skin reflex (40%). A skin biopsy revealed low intraepidermal nerve fiber density in 76% of the 17 tested patients.Compared to the 100 pSS patients without peripheral neuropathy, the 40 pSS-SFN patients were older at pSS diagnosis (55.3 ± 13.1 vs. 49.5 ± 14.9 yr; p = 0.03), and more often had xerostomia (97.5% vs. 81%; p = 0.01) and arthralgia (82.5% vs. 65.0%; p = 0.04). Immunologically, they were characterized by a lower prevalence of serum B-cell activation markers, that is, antinuclear antibodies (65% vs. 85%; p = 0.01), anti-SSA (42.5% vs. 71%; p = 0.002), and anti-SSB (17.5% vs. 39%; p = 0.017); rheumatoid factor (32.5% vs. 66%; p = 0.0005); and hypergammaglobulinemia (35% vs. 62%; p = 0.005).In conclusion, we report the main features of SFN in patients with pSS, the first such study to our knowledge. Our results show that patients with pSS-associated SFN are characterized by an older age at pSS diagnosis and a distinctive immunologic profile hallmarked by a lower frequency of serum B-cell activation markers.

Samuel Goldflam (1852–1932)

Samuel Goldflam (1852–1932)

Pain-related evoked potentials: A comparative study between electrical stimulation using a concentric planar electrode and laser stimulation using a CO2 laser

To compare the pain-related evoked potentials (PREPs) obtained by superficial electrical stimulation using a concentric planar electrode to those obtained by CO2 laser stimulation. In 12 healthy subjects, PREPs, sympathetic skin reflexes (SSRs), motor reaction times (mRTs), and the conduction velocity (CV) of the recruited nerve fibres were assessed in response to electrical and laser stimulation. In response to superficial electrical stimulation, PREP latencies and mRTs were shorter, while PREP amplitude tended to be increased. By contrast, SSR amplitudes and latencies and estimated CVs of the stimulated nerve fibres did not differ between electrical and laser stimulation. Fifteen minutes after PREP recordings, the residual pain intensity and the degree of unpleasantness were higher for laser stimulation than for electrical stimulation. In addition, CO2 laser stimuli induced dyschromic spots on the skin. For these reasons, all subjects declared that they would prefer superficial electrical stimulation rather than CO2 laser stimulation if they had to perform PREPs again. The estimated CVs of the recruited nerve fibres and the localized pinprick sensation felt by the subjects suggest that small-diameter fibres in the A-delta range, conveying "first-pain" information, were stimulated in response to superficial electrical stimulation as for laser stimulation. Superficial electrical stimulation using a concentric planar electrode could be a valuable alternative to laser stimulation for assessing PREPs in the practice of clinical neurophysiology.

MIBG scintigraphy for differentiating Parkinson's disease with autonomic dysfunction from Parkinsonism‐predominant multiple system atrophy

Parkinson's disease (PD) with autonomic dysfunction is difficult to differentiate from Parkinsonism-predominant multiple system atrophy (MSA-p). This study aimed to analyze the validity of MIBG scintigraphy for PD with autonomic dysfunction and MSA-p. Thirty-nine patients (PD: 27 patients, MSA-p type: 12) and 12 age-matched controls were prospectively enrolled and underwent MIBG scintigraphy and autonomic function test (AFT). We separately calculated early and delayed heart-to-mediastinal (H/M) ratio and washout rates (WRs). AFT was composed of sympathetic skin reflex and parasympathetic tests based on heart rate variability. Abnormal AFT was observed in 17 (63%) of PD and 10 (83%) of MSA-p. On comparing PD with abnormal AFT with MSA-p, either the early or delayed H/M ratio in PD was not different from that in MSA-p (P > 0.05). Only the WR could differentiate PD with abnormal AFT from MSA-p (47.07 +/- 57.48 vs. 31.39 +/- 31.52, respectively) (P = 0.026). According to the results, WR may be more useful than the early and delayed H/M ratio to distinguish MSA-p from PD with abnormal AFT. Furthermore, the MIBG uptake did not reflect the disease duration or severity.

Studies on the systemic features of autonomic diabetic neuropathy

Thirty diabetics with peripheral neuropathy underwent complex assessment of autonomic nervous disorders of seven different organ systems. Functional analysis was done of the cardiovascular system (respiratory arrhythmia at rest and during regulated breathing, 3rd order waves of cardiac frequency and of arterial mean pressure, active and passive orthostasis), pupillary regulation (infra-red pupillography), peripheral vasomotor regulation (skin temperature) and sudomotorics (psychogalvanic skin reflex). Involvement of the genitourinary system, of stomach and intestine was evaluated by clinical criteria. Twelve diabetics showed signs of autonomic neuropathy in four to six, eight patients in three organ systems. The amplitudes of respiratory arrhythmia during regulated breathing, spectral analytic evaluation of cardiac frequency waves of 3rd order and cardiac frequency immediate reaction during orthostasis were particularly indicative. The demonstrated disturbance of conduction of centrally generated cardiac frequency waves of 3rd order and the diminished amplitudes of the spontaneous rhythms of acral skin temperatures complement the previously known symptomatology of autonomic diabetic neuropathy. The systemic character of autonomic diabetic neuropathy objectivated by the investigations indicates a metabolic pathogenesis.

Observations on the Blink Reflex

The blink reflex and its equivalent glabella tap reflex are behavioural motor responses normally found in neonates and in the physiological startle reflex. Historically, it was described by Overend in 1896 and soon afterwards by McCarthy and by Bekhterev who disputed its origins. Kugelberg in 1952 recorded the early-latency R1 and the late-latency R2 electromyographic responses from orbicularis oculi and considered the blink reflex to be ‘a true skin reflex’. The mechanisms and clinical diagnostic value are discussed.