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Clinical aspects of multifocal or generalized tonic dystonia in reflex sympathetic dystrophy.

The authors describe 10 patients with reflex sympathetic dystrophy that progressed to a multifocal or generalized tonic dystonia. The neuropsychologic profile was similar to that of other patients with chronic pain, irrespective of its cause. The distribution pattern of dystonia, the stretch reflex abnormalities, and the worsening of dystonia after tactile and auditory stimuli suggest impairment of interneuronal circuits at the brainstem or spinal level. Antibody titers for glutamic acid decarboxylase, tetanus, and Sjögren antigens were all normal.

Adolescent↗

Hepatic retinopathia. Changes in retinal function.

In patients suffering from hepatic failure, the brain is subject to defined morphological and functional changes known as hepatic encephalopathia (HE). The morphological changes are dominated by glial cells (Alzheimer-type II astrocytes). It has recently been possible to demonstrate, that the retinal glia (Müller) cells undergo similar morphological changes. The present study was carried out in order to reveal if these Müller cell changes cause any characteristic functional deficits. We examined 11 patients with different stages of HE due to liver cirrhosis. Six patients were at stage 0 or 1 (group I) and five at stage 2 or 3 (group II). They underwent ophthalmological routine examination, colour vision testing and standard ERG recording. None of the patients reported impaired vision, in daylight or at night. There were no fundus abnormalities except very mild changes of the pigment epithelium and abnormal reflexes of the inner limiting membrane, especially in the higher HE stages. The number of confusions in the colour arrangement test increased with the higher stages of HE, preferably in the tritan axis. The scotopic a- and b-waves of the electroretinogram (ERG) were almost unchanged in group I and significantly decreased and delayed in group II. The photopic ERG b-wave amplitudes were changed in a similar fashion. Oscillatory potentials proved to be most sensitive to hepatotoxic changes. Their latencies were significantly delayed even in group I. Amplitudes were decreased significantly only in group II. Patients suffering from hepatic failure and accompanying HE display functional abnormalities of the retina. These are best demonstrated by the ERG, and correlate well with the degree of HE. A hypothesis is presented that relates the observed functional changes to altered neurotransmitter levels and impaired retinal glial-neuronal interaction, due to Müller cell damage caused by elevated ammonia levels.

Adult↗

[Malignant vasovagal syncope].

The diagnosis of epilepsy is complicated by various conditions that can mimic an epileptic seizure. Many patients with abnormal seizure activity during loss of consciousness may have cardiovascular syncope with global cerebral hypoxia (convulsive syncope), which may be difficult to differentiate from epilepsy on clinical grounds. The differentiation is, however, important because they need quite different treatment modalities. In addition, long-term anticonvulsant therapy is expensive and can cause serious morbidity. The authors present a case of a patient thought to have treatment-resistant epilepsy for years with recurrent seizure-attacks, who were subsequently found to have a malignant vasovagal reaction of 24s-asystole as a cause for the so called convulsive syncope. A simple, non-invasive evaluation of circulatory responses to acute orthostasis, the head-up tilt table test, can identify cardiovascular reflex abnormalities in patients with recurrent idiopathic seizure-like episodes. The authors could also reproduce the symptoms of the spontaneous attacks in their patient by this way, to confirm an alternative diagnosis of malignant vasovagal reaction and convulsive syncope in this patient with "refractory epilepsy". This rare cardioinhibition can be safely treated by dual-chamber pacemaker implantation, alleviating for the convulsive attacks, this therapeutic option was advised to this patient as well. Orthostatic stress tests should be considered early in the diagnostic workup of patients with convulsive blackouts. Cardiac causes of loss of consciousness should be considered in patients with presumed epilepsy, atypical premonitory symptoms, non-diagnostic electroencephalograms and failure to respond to anticonvulsant therapy.

Adult↗

[Retrocochlear hearing disorders].

The diagnosis of retrocochlear hearing impairment is mainly based on threshold tone decay, absence of the stapedius reflex, abnormal dichotic speech discrimination and ERA findings. A relatively poor discrimination for monosyllables with regressive understanding at high intensities can also indicate a neural or central lesion provided that the unaffected side has been correctly masked. ERA results mainly show a synchronisation disorder within the brain-stem, i.e. the J V-response is prolonged or cannot be recorded at all. The cortical response N1, however, corresponds to the subjective threshold except that in impairments of the cortex, the N1-response is worse than expected from the pure tone threshold. Representative examples are given.

Adolescent↗

Calf blood flow during prolonged tilt in idiopathic dilated cardiomyopathy and after cardiac transplantation.

In severe congestive heart failure (CHF), abnormal reflex control of calf blood flow during brief head-up tilt that appears to normalize after transplantation (HTX) may be present during prolonged observation also. Therefore, we studied the effect of prolonged (30 min) 50 degrees head-up tilt on calf skeletal muscle blood flow measured by the local (133)Xe washout method in CHF and after HTX and in patients with the presence vs. absence of native right atrium (+PNA and -PNA, respectively). During brief head-up tilt, skeletal muscle blood flow increased 13 +/- 42% in 9 severe CHF patients in contrast to a -28 +/- 22% decrease (P < 0.01) in 11 control subjects, -24 +/- 30% decrease in 15 moderate CHF patients (P < 0.05), -25 +/- 14% decrease in 12 patients with recent HTX (P < 0.01), and -21 +/- 24% decrease in 8 patients with distant HTX (P = 0.06). However, during sustained tilt, blood flow declined to similar levels of that in the other groups in severe CHF. HTX -PNA vs. +PNA showed blunted skeletal muscle vasomotor control (P < 0.05) and a higher systolic blood pressure (139 +/- 14 vs. 125 +/- 15 mmHg, P < 0.05) and heart rate (92 +/- 10 vs. 83 +/- 8 beats/min, P < 0.05). Thus paradox vasodilatation of calf skeletal muscle in severe CHF is present only during brief but not prolonged tilt. This may be one explanation of the rare presence of orthostatic intolerance in CHF and implies only a minor possible role for the abnormality in edema pathogenesis. Removal of all right atrium in HTX has an important hemodynamic impact that may possibly affect later clinical outcome.

Adult↗

Hyperekplexia exacerbated by occlusion of posterior thalamic arteries.

A 65-year-old man with the onset of hyperekplexia at 37 years of age experienced resolution of the illness at the age of 45 years. Twenty years later after a posterior thalamoperforate artery occlusion that produced a "rubral tremor," severe hyperekplexia redeveloped. The patient's symptoms were controlled with clonazepam, except for brief periods. Interruption of the rubrothalamic pathways or neuronal aggregates at the level of the red nucleus seemed to disinhibit the startle reflex.

Acute Disease↗

Hyperekplexia.

Hyperekplexia is a hereditary neurologic disorder manifested by an exaggerated startle response, generalized muscular rigidity, and prominent nocturnal myoclonus. The distinctive features of this syndrome constitute an unusual clinical entity that is easily mistaken for other disorders. The study of a family provided additional data on various aspects of this condition. The proband was 3 months old when he was referred for persistent generalized stiffness since birth; this stiffness was associated with an exaggerated startle response and intermittent apnea. Similar symptoms in infancy and prominent nocturnal myoclonus with an excessive startle response in adulthood were described in other family members for five generations. Various features of the disorder indicate a relationship to the syndrome of the "jumping Frenchmen of Maine," latah, miryachit, and other unusual startle reactions.

Humans↗

Oculosympathetic spasm with cervical spinal cord injury.

A 23-year-old man, involved in a motor-vehicle accident, became quadraparetic due to cervical spinal cord injury at the C-4 to C-6 level. Five months later he was noted to have bilateral, asymmetric pupillary mydriasis precipitated by elevation and stretch of an arm or leg. Pharmacologic pupillary testing and ciliospinal reflex responses suggested that the oculosympathetic pathways were intact. Computed tomographic myelography using metrizamide disclosed a posttraumatic syringomyelic cyst at C-4. This pupillary phenomenon has been termed oculosympathetic spasm, and we reviewed four previous reports. While the cause of oculosympathetic spasm remains speculative, it may represent a localized form of autonomic hyperreflexia.

Accidents, Traffic↗

Babinski's sign in medieval, Renaissance, and baroque art.

In 1896, Joseph François Babinski first described his well-known sign of dorsiflexion of the big toe on stimulating the sole of the foot. However, unknown to Babinski, several painters had previously demonstrated this phenomenon in their paintings. Sandro Botticelli (1445-1510), a Florentine Renaissance painter, demonstrated this reflex in his Madonna and Child with Angels 400 years before the publication of Babinski's discovery. Botticelli used live infants as models for his paintings. Gentile da Fabriano (d 1427) in his Adoration of the Kings, demonstrates a similar response of toe extension in the infant Jesus when one of the Magi kisses the baby's foot. Similarly, Jacob Schick von Kempter, a 16th century German painter, in his Coronation of the Virgin demonstrates the extensor plantar response in the infant. Correggio (1492-1534), in northern Italy captured the extension and flare of the baby's toes in his Madonna and Child with Mary Magdalen. Raphael (1483-1520) presented the extensor plantar responses in the child when sole pressure is applied in Small Cowper Madonna. Leonardo da Vinci, with his nude model drawings (1503-1507) seemed to have been aware of this response. There is no indication that any of these artists fully understood the physiology behind the response; therefore, the value of this sign in neurologic disease must still rely on Babinski's demonstration several hundred years after its initial demonstration in artistic literature.

Child↗

Startle responses in hereditary hyperekplexia.

BACKGROUND: Patients with hereditary hyperekplexia have excessive startle responses that are accompanied by transient stiffness and also continuous stiffness in infancy. A point of mutation has been identified for the major form of hereditary hyperekplexia in the gene encoding the alpha 1 subunit of the glycine receptor. OBJECTIVE: To measure startle reflexes and autonomic responses in the major form of hereditary hyperekplexia in the original Dutch pedigree. DESIGN: Startle reflexes and autonomic responses were examined by administering 3 series of 20 auditory stimuli at intervals of 10 seconds (90 and 113 dB) and 60 seconds (113 dB). SETTING: The Department of Neurology and Clinical Neurophysiology at the Leiden University Hospital, Leiden, the Netherlands. SUBJECTS: Nine patients with the major form of hyperekplexia and 20 healthy controls. Of the 9 patients, 5 took medication. The patients are part of the Dutch hyperekplexia pedigree. MAIN OUTCOME MEASURES: Startle responses were quantified with latency periods and areas of electromyographic bursts of the orbicular muscle of the eye, sternocleidomastoid and biceps muscles, and the thenar muscles. Autonomic reactions were measured with psychogalvanic responses and beat to beat changes of blood pressure and heart rate. RESULTS: The electromyographic bursts of the 4 muscles occurred in similar order in both patients and controls. The onset of the latency periods in the patient group was significantly (P < .001) prolonged in patients who took medication. Without medication, patients had shorter latency periods of the sternocleidomastoid muscle (P = .003) than controls. The electromyographic burst occurred significantly more often in patients than in controls (P < .001). The areas of the bursts were significantly larger in patients than in controls (P < .001); the degree of habituation was significantly stronger in patients than in controls (P < .001). The amplitude of the psychogalvanic response was increased in hyperekplexia, and the degree of habituation was significantly weaker in patients than in controls. Blood pressure and heart rate did not clearly react in either group. CONCLUSIONS: Motor startle responses are stronger and show more habituation in patients with hereditary hyperekplexia than in controls. The excessive responses include the psychogalvanic response. Increased responses do not necessarily indicate decreased habituation in hyperekplexia.

Acoustic Stimulation↗