ABSTRACT
Forty nine elderly patients with osteochondrosis of the cervical spine and on whom carotid angiography had been performed were divided into two groups. In one 36 patients had vestibular symptoms whereas the other group of remaining patients was free of such symptoms. Comparison of both groups showed that vertigo (20 patients), other vestibular symptoms or nystagmus were not solely related to vertebral artery stenosis. In fact stenosis of one or both vertebral arteries was found in only nine patients.
Subject(s)
Arterial Occlusive Diseases/complications , Vertebral Artery , Vertigo/etiology , Aged , Cervical Vertebrae , Humans , Middle Aged , Nystagmus, Pathologic/etiology , OsteochondritisABSTRACT
Extraocular motor unit activity was recorded electromyographically from the lateral and medial rectus muscles in eight normal subjects, together with their EOGs. Twelve motor units showed a discharge pattern characterized by regular firing during positions of fixation, a burst of saccadic "on" activity and complete silence during saccades in the "off" direction. Two other units seemed to be phasic or predominantly phasic. Interval analysis in 7 of the above 12 units during positions of fixation showed a linear rate position relationship of the units together with an extreme regularity of consecutive discharge intervals. The peak frequency of saccadic motor unit activity occurred at the onset of the burst and increased with increasing size of the saccade up to 15--20 degrees. The motor units stopped firing a few milliseconds before the onset of a saccade in the "off" direction but resumed their activity before the end of the eye movement, with an instantaneous discharge rate which was greater than the post-saccadic discharge rate. It was shown that the antagonist muscle plays an active part to end the saccade by serving as a brake.
Subject(s)
Eye Movements , Motor Neurons/physiology , Oculomotor Muscles/innervation , Saccades , Adolescent , Adult , Electromyography , Electrooculography , HumansSubject(s)
Disability Evaluation , Multiple Sclerosis , Adolescent , Adult , Age Factors , Child , Female , Humans , Male , Middle Aged , Multiple Sclerosis/diagnosis , Multiple Sclerosis/physiopathology , Muscle Spasticity , PrognosisABSTRACT
Angiographic and/or operative follow up studies on 19 patients with angiographically demonstrated subtotal carotid artery stenosis showed the following results: In 3 out of 16 cases where no immediate operation of the stenosis was performed, complete occlusion followed within a week of the angiographic demonstration of the stenosis. Though intramural artifacts did not occur, this could be a consequence of the angiographic procedure (temporary fall of blood pressure?). In 4 out of 7 cases with subtotal stenosis where the diagnosis was known for at least 6 months, no occlusion occurred. The blood flow through a subtotal carotid artery stenosis might not be as small as is usually assumed, as illustrated by 2 out of 3 cases where a definite increase in the symptoms occurred on complete occlusion of the the vessel. The results indicate that cases of subtotal stenosis should be promptly treated by disobliteration.
Subject(s)
Arterial Occlusive Diseases/physiopathology , Carotid Artery Diseases/physiopathology , Arterial Occlusive Diseases/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Constriction, Pathologic , Follow-Up Studies , Humans , RadiographyABSTRACT
A "spontaneous" dissecting aneurysm of the petrous portion of the right internal cartoid artery in a 60 year old man was demonstrated angiographically. It showed a typical double lumen which is rarely demonstrated by angiography. It was probably of atherosclerotic origin. In addition, a survey of the positions and angiographic characteristics of the 29 traumatic and "spontaneous" dissecting aneurysms of the common and internal carotid arteries found in the literature is presented.
Subject(s)
Carotid Artery, Internal , Intracranial Aneurysm/diagnostic imaging , Carotid Artery, Internal/diagnostic imaging , Cerebral Angiography , Humans , Intracranial Aneurysm/epidemiology , Intracranial Aneurysm/pathology , Male , Middle AgedSubject(s)
Carotid Artery, Internal/diagnostic imaging , Adult , Aneurysm/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Female , Humans , Intracranial Embolism and Thrombosis/diagnostic imaging , Male , Middle Aged , Prognosis , Radiography , Remission, Spontaneous , Time FactorsABSTRACT
Interval analyses of denervation potentials (fibrillation-potentials and positive sharp waves) in human skeletal muscles were performed using a DEC PDP-12 computer. Extremely small differences between consecutive intervals (usually less than 1%) and slow up and down drifts in the spontaneous discharge frequency were found to be characteristic of repetitive denervation potentials. These two findings are safe criteria for the clinical diagnosis of denervation and they may be superior to the more commonly used criteria based upon the shapes, amplitudes, and durations of the potentials. Physiological data from the literature as well as hypotheses relating to spontaneous activity are reviewed. Generator potentials across the muscle fibre membrane, lowered firing threshold, and constant-sized after-potentials are considered the basic factors relevant to spontaneous and rhythmical firing and to the slow drift observed in the firing frequency.
