John Gilroy

Auscultation of the Neck in Occlusive Cerebrovascular Disease

D URING the last decade the importance of atherosclerosis of the carotid and vertebral arteries in the neck as a eause of cerebral ischemia or infaretion has become recognized. This has led to revision of older views that cerebral infaretion almost invariably resulted from oeclusion of the middle cerebral or the intracranial arteries. Recent arteriographic and pathologic studies have demonstrated frequent stenosis of one or both carotid or vertebral arteries in the neck in patients with cerebrovascular symptoms.1- It is evident from routine examination of the cervical and cranial vessels in unselected cases at necropsy,j in subjects dying of stroke and by arteriography in the living, that atherosclerotic plaques occur most frequentlyin well-defined sites of the internal. carotid vessels. The commonest site for plaque formation is in the internal carotid artery witlh atherosclerotic stenosis or occlusion in the region of the carotid sinus, usually at the origin of the internal from the comnmion carotid artery or a few eentimeters distal to this point.7 Surgical removal of atheroselerotic. plaques at this site is quite feasible anid an impressive number of successful. cases have been reported.3 -16 Atherosclerotic plaques of the vertebral-basilar arterial svstem are usually more diffuse. The commonest site is the basilar artery itself. Meyer, Sheehan, and Bauer17 in an arteriographic study of subjects admitted to a general hospital with

Syringomyelia affecting the entire spinal cord secondary to primary spinal intramedullary central nervous system lymphoma.

A case of syringomyelia involving the entire spinal cord secondary to a spinal intramedullary tumour is described. Cerebrospinal fluid cytology and microscopic evaluation of gross necropsy specimens revealed a primary large cell lymphoma of the central nervous system. In addition there was massive leptomenigeal lymphomatosis involving the cortex, brainstem, and cerebellum. No solitary intracranial mass lesion was found.

Clinical, biochemical and neurophysiological studies of chronic interstitial hypertrophic polyneuropathy

Abstract Clinical, biochemical and neurophysiologic studies in a series of patients with chronic interstitial hypertrophic neuropathy indicate that no similar disorder of lipid metabolism exists as reported in some cases of Refsums syndrome with hypertrophic neuropathy. The two conditions are therefore different, although the pathologic changes in the peripheral nerves are said to be similar. In this series, chronic interstitial hypertrophic neuropathy was characterized by remissions and exacerbations which may be provoked in some instances by thiamine deficiency, and at least some cases appear to have disordered thiamine utilization.

Studies of cerebral circulation time in man: 1 Normal values and alterations with cerebral vascular disease and tumour in arm-to-retina circulation times

During an extensive arteriographic investigation of subjects with arteriosclerotic, atherosclerotic, and thrombotic cerebral vascular disease, considerable delay has often been observed in opacification of the small cerebral arteries (Meyer, Sheehan, and Bauer, 1960; Sheehan, Bauer, and Meyer, 1960; Bauer, Sheehan, and Meyer, 1961; Bauer, Sheehan, Wechsler, and Meyer, 1962). The delay in filling is probably due to slowing of the cerebral circulation and in some cases it has been necessary to delay exposure of radiographs for one to five seconds in order to obtain satisfactory visualization of the intracranial vessels. Such prolongation of the circulation time, demonstrated arteriographically, has now been confirmed in some of our cases of cerebral vascular disease by the use of the SanchezPerez serial casette changer and a timing device. Slowing of the cerebral circulation time has also been shown following experimental cerebral embolism or occlusion of the middle cerebral artery (Meyer, 1958; Meyer, Gotoh, and Tazaki, 1962). Such observations led us to the hypothesis that simple bedside measurement of the arm-to-retina circulation times might be a valuable, although indirect, method of evaluating slowed cerebral circulation in embolic, thrombotic, arteriosclerotic, and atherosclerotic cerebral vascular disease. The arm-to-retina circulation time has been evaluated previously in the diagnosis of carotid artery occlusion by comparison of the circulation times of the two sides (David, Saito, and Heyman, 1961; Hollenhorst and Kearns, 1961; Heyman, 1961) but not in other forms of cerebral vascular disease. Theoretically, arm-to-retina circulation times should vary with cardiac output, systemic vascular resistance, cerebral vascular resistance, vascular resistance of the external carotid circulation, retinal

PITUITARY INSUFFICIENCY WITH CEREBROVASCULAR SYMPTOMS. A NEW CLINICAL SYNDROME.

THE common association of hypertension and atherosclerosis of vertebral and basilar arteries supplying the brain-stem and cerebellum has been established by clinical and pathological studies.1 , 2 It has been our observation, however, that the development of symptoms in patients with vertebralbasilar insufficiency is often precipitated by a fall in blood pressure from previously higher levels. During the period of hypertension an adequate or marginal cerebral circulation is maintained, but if the blood pressure falls or fluctuates, the perfusion pressure may be periodically insufficient to meet the metabolic requirements of the hindbrain. There are other causes of circulatory failure such as thrombosis .xa0.xa0.

Serum enzyme levels in patients with myasthenia gravis after aerobic and ischaemic exercise

This study was designed to test the hypothesis that there is a myopathic component in myasthenia gravis. Serum enzyme analyses and lactate and pyruvate assays were undertaken before and after exercise in order to detect possible leakage from defective muscle membrane. A patient and a control group were exercised under (1) aerobic conditions, (2) ischaemic conditions, and (3) aerobic conditions under the influence of edrophonium chloride. The patient group showed a higher resting level of lactate in the aerobic state than did the controls. In addition, the average change in SGOT values in the patient group after one minute of aerobic exercise under the influence of edrophonium chloride exceeded that of the control group. Both these findings suggest possible leakage of enzyme and metabolite from the myasthenic muscle due to a membrane defect and support the hypothesis that there may be a myopathic component in myasthenia gravis. However, the two groups showed no significant differences in CPK values, which are often elevated in primary muscle diseases.