Cumhur Ertekin

BULBOCAVERNOSUS REFLEX IN NORMAL MEN AND IN PATIENTS WITH NEUROGENIC BLADDER AND/OR IMPOTENCE

The bulbocavernosus reflex was investigated electrophysiologically in 14 normal adult male subjects and in 80 patients with neurogenic bladders and/or impotence due to various neurological causes as well as in patients with functional impotence. The glans penis was stimulated superficially by single electrical shocks and the reflex responses were recorded from the bulbocavernosus (BC) and the striated anal sphincter muscles by means of concentric needle EMG electrodes. In all normal subjects, the BC reflex was recorded from the BC muscle as a stable and constant response having a mean latency of 36.1 msec. A response from the external anal sphincter was obtained in only 21% of the subjects investigated. In 13 patients with cauda equina lesions, the BC reflex was either absent or was present with a prolonged latency. Twenty-two patients with polyneuropathy of various causes were also investigated; in these patients the latency of the BC reflex was significantly greater than in the normal controls, but the most abnormal results were obtained in cases of alcoholic polyneuropathy. In the 19 cases of spinal cord disease with spasticity the BC reflex response was very intense, often with after discharges but latency values were within normal limits. In the 16 cases with functional impotence, the BC reflexes were basically normal; but in 3 cases, the threshold of the reflex was significantly raised, and in 1 case a prolonged latency was observed. The value and the practical application of the BC reflex in the BC reflex in the differential diagnosis of bladder dysfunction and of impotence was stressed.

Electrophysiological evaluation of pharyngeal phase of swallowing in patients with Parkinson's disease

We studied the various physiological aspects of oropharyngeal swallowing in Parkinsons disease (PD). Fifty‐eight patients with PD were investigated by clinical and electrophysiological methods that measured the oropharyngeal phase of swallowing. All patients except 1 had mild to moderate degree of disability score. Dysphagia was demonstrated in 53% of all patients in whom the test of dysphagia limit was abnormal. All PD patients with or without dysphagia displayed the following abnormalities: (1) the triggering of the swallowing reflex was prolonged probably due to inadequate bolus control in the mouth and tongue and/or a specific delay in the execution of the swallowing reflex; (2) the duration of the pharyngeal reflex time was extremely prolonged due to slowness of the sequential muscle movements, especially those of the suprahyoid‐submental muscles; (3) cricopharyngeal muscle of the upper oesophageal sphincter was found to be electrophysiologically normal; and (4) the electrophysiological phenomena in PD patients could not be strongly correlated with the degree of the disability and clinical score of the PD. It was concluded that various motor disorders of PD have considerable influence on oropharyngeal swallowing: hypokinesia, reduced rate of spontaneous swallowing, and the slowness of segmented but coordinated sequential movements rather than any abnormalities in the central pattern generator of the bulbar center. Some compensatory mechanisms in the course of PD may explain the benign nature of swallowing disorder until the terminal stage of the disease. Similarly, the swallowing problems of PD are not only related with the dopamine deficiency; some other nondopaminergic mechanisms may also be involved.

Piecemeal deglutition and dysphagia limit in normal subjects and in patients with swallowing disorders.

OBJECTIVE: Before the advanced evaluation of deglutition and selection of a treatment method, objective screening methods are necessary for patients with dysphagia. In this study a new electroclinical test was established to evaluate patients with dysphagia. METHODS: This test is based on determining piecemeal deglutition; which is a physiological phenomenon occurring when a bolus of a large volume is divided into two or more parts which are swallowed successively. The combined electrophysiological and mechanical method used to record laryngeal movements detected by a piezoelectric transducer, and activities of the related submental integrated EMG (SM-EMG)-and sometimes the cricopharyngeal muscle of the upper oesophageal sphincter (CP-EMG)-were performed during swallowing. Thirty normal subjects and 66 patients with overt dysphagia of neurogenic origin were investigated after detailed clinical evaluation. Twenty patients with a potential risk of dysphagia, but who were normal clinically at the time of investigation, were also evaluated to determine the specificity of the test. All subjects were instructed to swallow doses of water, gradually increasing in quantity from 1 ml to 20 ml, and any recurrence of the signals related to swallowing within the eight seconds was accepted as a sign of dysphagia limit. RESULTS: In normal subjects as well as in the patients without dysphagia, piecemeal deglutition was never seen with less than 20 ml water. This volume was therefore accepted as the lower limit of piecemeal deglutition. In patients with dysphagia, dysphagia limits were significantly lower than those of normal subjects. CONCLUSION: The method is a highly specific and sensitive test for the objective evaluation of oropharyngeal dysphagia even in patients with suspected dysphagia of neurogenic origin. It can also be safely and simply applied in any EMG laboratory.

Electrodiagnostic methods for neurogenic dysphagia

OBJECTIVE Swallowing mechanisms and neurogenic dysphagia have not been systematically studied by the EMG technique. It is desirable to evaluate neurogenic dysphagia for diagnostic and possibly for therapeutic purposes using electrophysiological methods. METHODS The following methods were described: mechanical upward/downward movements of the larynx were detected using a piezoelectric sensor, while submental integrated EMG activity was recorded during dry and wet swallowing. The EMG activity of cricopharyngeal muscle of the upper oesophageal sphincter was also recorded in some normal subjects and patients. Piecemeal deglutition and the dysphagia limit were determined in all patients to detect dysphagia objectively. In this study 75 normal subjects and 177 neurological patients with various degrees of dysphagia were investigated. RESULTS Voluntarily triggered oropharyngeal swallowing was commonly pathological in the majority of patients, with or without overt dysphagia. The dysphagia limit appeared to be an objective measure of the degree of dysphagia in more than 90% of patients. Pathophysiological mechanisms were different in at least three groups of patients with neurogenic dysphagia. In the group of patients with muscular disorders, laryngeal elevators were involved while the CP-sphincter was intact. The second group included patients with the clinical signs of corticobulbar fibre involvement such as amyotrophic lateral sclerosis and pseudobulbar palsy. In these patients, there was incoordination between paretic laryngeal elevators and hyperreflexic CP-sphincter. In the third group (patients with Parkinsons disease), the swallowing reflex was delayed and prolonged. CONCLUSIONS EMG methods described in the present study are very useful for the diagnosis of neurogenic dysphagia, objectively and quickly. They are important to understand the physiological mechanisms for deglutition and its disorders.

Use of levodopa to relieve pain from painful symmetrical diabetic polyneuropathy

&NA; Levodopa has been used to treat some painful conditions and found to be effective in neuropathic pain due to herpes zoster in a double‐blind study. From our anecdotal observations about the efficacy of levodopa on diabetic neuropathic pain, we designed a double‐blind placebo‐controlled study to test levodopa in painful diabetic neuropathy. Twenty‐five out‐patients with painful symmetrical diabetic polyneuropathy were admitted to the study. Fourteen patients were given 100 mg levodopa plus 25 mg benserazide to be taken three times per day for 28 days. Eleven patients were given identical placebo capsules. A blinded neurologist evaluated the patients clinically and performed Visual Analogue Scale (VAS) measurement every week from day 0 to day 28. The results seemed promising and levodopa may be a choice for the control of pain in neuropathy for which we do not have many alternative treatments.

STUDIES ON THE HUMAN EVOKED ELECTROSPINOGRAM

Evoked potentials from the human spinal cord were studied in 39 normal volunteers. Intrathecal recordings from lower cervical and lower thoracic intervertebral levels were made after the supramaximal stimulation of the median, ulnar and posterior tibial nerves, respectively. It was shown that the segmental cord potentials varied in shape and size according to the spatial relationship between the position of the electrode tip and the spinal cord and roots within the vertebral canal. Three main types of segmental evoked responses were obtained. One of them was recorded behind the cord dorsum and around the midline, and was composed of fast, sharp early, and slow, late components. This was called a CD potential and its first component was related to the activity of the ascending dorsal funiculus fibres. the second evoked response was the DR potential, and this triphasic compound action potential of very high amplitude and longer duration had no remarkable late component. It was recorded when the tip of the intrathecal electrode was lateral to the midline within the vertebral canal, and was then related mostly to activity of the spinal roots. Another kind of potential was called PH potential. It had a very small triphasic spike and two later components with prominent negativities being higher than the first spike. This potential might be related to the electrode tip position facing, and close to, the posterior horn of the spinal gray matter. Late components of the segmental evoked potentials were related to the pre‐ and post synaptic activity of the horizontally oriented fibres within the segmental gray matter of the posterior horn.

The value of somatosensory-evoked potentials and bulbocavernosus reflex in patients with impotence

ABSTRACT – In 14 normal male adults and 97 male patients having impotence alone or together with systematic and/or neuro‐psychiatric symptoms and signs, the somatosensory cerebral‐evoked potentials were obtained by glans penis stimulation (penile SEP); by peroneal nerve stimulation (peroneal SEP) and by electrically‐induced bulbocavernous (BC) reflex. In normal subjects, the configurations of both SEPs were basically similar, except that the onset of latency was 10–15 msec longer and the amplitude in the P1‐N1 component was higher in penile SEP. BC‐reflex latency was abnormally prolonged, especially in diabetic impotence and in patients with cauda/conus lesions, while the abnormalities on the penile and peroneal SEP were more frequent in patients with spinal cord injuries, MS and parkinsonism. In impotent patients with epilepsy, chronic prostatitis and psychogenic problems, all the tests were generally normal.

Voluntary and Reflex Influences on the Initiation of Swallowing Reflex in Man

The electrophysiological features of voluntarily induced and reflexive/spontaneous swallows were investigated. In normal subjects, swallows were elicited by infusing water either into the mouth (1–3 ml) or directly into the oropharyngeal region through a nasopharyngeal cannula (0.3–1 ml). For water infused orally, subjects were either requested to swallow voluntarily or instructed to resist swallowing and maintain the horizontal head position until swallowing occurred reflexively. Spontaneous saliva swallowing was investigated in patients with severe dysphagia who had a prominent clinical picture of suprabulbar palsy. Comparisons between different swallowing types were made by measuring the time interval between the onset of submental electromyographic activity (SM-EMG) and the onset of the upward movement of the larynx recorded by a movement sensor. This interval was less than 100 ms, even frequently less than 50 ms, in reflexive/spontaneous swallows, while in voluntarily induced swallows it was substantially longer. The rising time of submental muscles excitation was also shorter in reflexive/spontaneous swallows. It was suggested that the triggering of voluntarily induced swallows commences more than 100 ms before the onset of swallowing reflex and that this mechanism is under the control of corticobulbar–pyramidal pathways. If the swallowing reflex is triggered within such a short period of time following the onset of SM-EMG, the central control by the bulbar swallowing center should be effective until the end of oropharyngeal swallowing.

Skin potentials (SP) recorded from the extremities and genital regions in normal and impotent subjects.

Abstract Skin potentials (SP) were evoked by peripheral nerve stimulation from the hands and feet of 41 and from the genital skin of 28 male, controls. The same methods were also applied in 10 functionally impotent cases, 32 diabetic impotent and 8 diabetic normopotent cases. The SP was easily obtained from all 3 sites in all normal subjects and in 10 functionally impotent cases. The SP recorded from the genital skin was either absent or abnormal in 53% of diabetic impotent cases with or without polyneuropathy, while the incidence of abnormalities encountered in the hand and/or foot recordings was 28%. In 8 diabetic normopotent cases the SP recorded from the genital and extremity skin were completely normal. SP recorded from the genital skin is a useful method of evaluating the autonomic‐sympathetic dysfunction causing impotence, especially in patients who may have autonomic disorders either located in lumbosacral spinal cord and its efferents, or generalized autonomic‐peripheral dysfunction.

Mechanisms of Dysphagia in Suprabulbar Palsy With Lacunar Infarct

BACKGROUND AND PURPOSE The objective of the present study was to investigate the neural mechanisms of dysphagia in suprabulbar palsy (SBP) with multiple lacunar infarct. METHODS We evaluated the swallowing disorders of patients with SBP (n=34) and age-matched healthy control subjects (n=35) by means of an electrophysiological method that recorded the oropharyngeal swallowing patterns. With this method, dysphagia limit, the triggering of voluntarily initiated swallows, duration of laryngeal relocation time, and total duration of oropharyngeal swallowing were recorded and measured. In addition, the EMG behavior of the cricopharyngeal (CP) muscle of the upper esophageal sphincter was also assessed. RESULTS In patients with SBP, the dysphagia limit in all except 1 patient was pathological with limits of <20-mL bolus volume, which is contrary to normal subjects, in whom the dysphagia limit exceeds the 20-mL bolus volume. Either triggering of swallowing reflex was delayed (P<0.04), or the swallow could hardly be triggered in 7 patients on the voluntary attempts for 3 mL water. Whenever the reflex swallowing could be triggered, it was slow and prolonged (P<0.01). The CP muscle of the upper esophageal sphincter appeared to have become hyperreflexic and incoordinated with laryngeal movements during swallowing. CONCLUSIONS It was proposed that the progressive involvement of the excitatory and inhibitory corticobulbar fiber systems linked with the bulbar swallowing center is mainly responsible for the triggering difficulties of the swallowing reflex and for the hyperreflexic/incoordinated nature of the CP sphincter. In addition, the dysfunction of the extrapyramidal system has a specific role in the slowing of oropharyngeal swallowing and the accumulation of saliva in the mouth.