The clinical diagnosis of Alzheimer's disease.

Clinical and pathologic diagnoses are compared in 65 patients who had dementia and who had been studied longitudinally during life. The sensitivity of diagnosis for dementia of the Alzheimer type (DAT) without any other diagnosis was 87%, and the specificity was 78%. The ischemic scale score did not discriminate well between patients with pure multi-infarct dementia and those with both DAT and multi-infarct dementia. However, 35 of 38 cases of pure DAT had a score of 4 or less on the ischemic scale.

Crossed anomic aphasia: mild naming deficits following right brain damage in a dextral patient.

A detailed case study is reported of crossed aphasia (CA) in a dextral patient, bearing upon such controversial issues as intrahemispheric localisation of language function and hemispheric reversal of nonverbal function. DA, a man aged 37, developed a mild naming problem due to right temporal lobe haematoma. Apart from a mild acquired stutter, his continuous speech was fluent and had a normal proportion of open to closed class lexical items. His naming deficit appears to originate in the 'blocking' or 'disconnection' of the phonological lexicon: he could usually give a functional definition of un-named items and retrieve them with the help of a phonemic cue. Lexical retrieval appears his only language deficit, as he had no comprehension or phonological discrimination deficits. DA showed no visuo-spatial or auditory-nonverbal deficits, suggesting the complete reversal of hemispheric specialisation.

Clinical application of an electronic imaging device for assisting patient set-up in radiotherapy.

As radiotherapy treatment set-ups are becoming more complicated and a greater emphasis is placed on accuracy, there is an increasing need to verify and record the actual treatments being given. A direct electronic imaging device is currently marketed by Varian (the DYNARAY ID), which uses the latest technology in detection and image processing to obtain digital images of the patient's anatomy using the actual treatment beam. At Norwich we have been using a prototype machine in a busy district radiotherapy centre and have examined over 50 patients. We have found the images easy to obtain and the technique superior to the standard practice of using verification radiographs. The role of this device lies in aiding quality assurance of treatments whilst generating a permanent record of the actual treatment given.

CT standard protocols are of limited value in assessing actual patient dose.

In the last 10 years the use of computed tomography in radiodiagnosis has increased markedly and CT scanners are now present in most district general hospitals. Modern CT scanners are versatile in their operation and offer the operator a wide choice in exposure parameters which affect the doses received by the patients. As CT is a major contributor to medical radiation doses, the National Radiological Protection Board (NRPB) recommends that an estimate of typical patient dose should be made for commonly used local scanning protocols. A survey has been undertaken in the Anglia and Oxford region covering 12 CT scanners. Common procedures were chosen, concentrating on those most frequently carried out and giving higher effective doses. These included routine heads, routine chests, high resolution chests and abdomen/pelvis examinations. Questionnaires were sent out to each CT centre to collect data on standard protocols and to record the procedure used for five actual patients for each examination type thus enabling a comparison of the two methodologies. This study has shown that many examinations are tailored to the individual patient size and clinical indications, particularly in the chest/abdomen/pelvis. Thus, assessing doses based on collecting standard protocols may not give a true indication of the effective doses being received by particular patients.

Wrist pain.

Acute and chronic wrist pain are problems frequently seen by primary care physicians. The impact of wrist pain on function is substantial and requires prompt attention and treatment by physicians. In this article we summarize the causes of wrist problems, provide an approach to wrist pain, and discuss some of the common disorders seen by primary physicians.

High resolution SPECT, small deep infarcts and diaschisis.

Eighteen cases of lacunar infarction are presented. Six of these cases had a purely motor clinical deficit. All the cases were studied by serial high resolution SPECT (single photon emission computerized tomography) using 99Tcm HMPAO. The degree and extent of the changes in cerebral perfusion consistent with diaschisis were noted and these compared with the severity of the clinical deficit at presentation and over time. No significant correlation between diaschisis and the clinical state was found at any stage. The nature, aetiology and importance of diaschisis are discussed and it is suggested that caution should be exercised in attributing clinical features to diaschisis simply because it may be present.

Stability of whole vs part perceptions of visual stimuli.

In two experiments, college undergraduates (ns = 29, 30) were asked to describe in writing two different abstract line drawings. Responses were classified by over-all orientation to the whole or the individual parts of each drawing. Although findings of the two experiments were very similar, analysis indicated that no strong reliability of orientation existed across the two drawings.

Multi-infarct dementia: prevention and treatment.

Multi-infarct dementia (MID) characteristically presents with an acute event followed by a stepwise and fluctuating downhill course. Progression is generally considered the consequence of recurrent stroke (Hachinski, 1983): the mainstay of treatment, therefore, is the prevention of further ischemic events.

Transport of oxygen to the brain in patients with elevated haematocrit values before and after venesection.

Cerebral blood flow and oxygen transport to the brain have been studied in 20 patients with primary polycythaemia, before and after venesection. Cerebral blood flow rose by an average of 30 per cent (P less than 0.001) when the mean haematocrit was reduced from 0.537 to 0.444. Whole blood viscosity fell predictably and the correlation coefficient between haematocrit and blood viscosity at a shear rate of 91 s-1 was 0.926 (P less than 0.001). Mean arterial blood pressure, arterial PCO2 and pH were not influenced by venesection. A small but significant overall rise in arterial PO2 was observed but the arterial oxygen content fell with the reduction in haemoglobin concentration. The product of cerebral blood flow and arterial oxygen content rose by an average of 8 per cent (P less than 0.001) and this was considered physiologically significant because the position of the oxygen dissociation curve did not change. The increase in oxygen transport to the brain may serve to protect against ischaemic insult and other mechanisms whereby elevated haemotocrit might predispose to cerebral infarction are briefly discussed.

Reactivity of the cerebrovascular bed to carbon dioxide in patients with primary high haematocrit before and after venesection.

Paired cerebral blood flow measurements at 2 levels of arterial carbon dioxide tension (PaCO2) were made in 10 subjects with an elevated haematocrit and blood viscosity. A value of 32 was obtained for the percentage change in flow per kPa change in PaCO2 (CO2 reactivity). The haematocrit was then lowered by venesection from 0.536 to 0.458 and the measurements were repeated. The post-venesection CO2 reactivity was 29, which was not significantly different from the pre-venesection value. Thus CO2 reactivity is not comprised in patients with low cerebral blood flow secondary to an elevated haematocrit.

Post-menopausal Osteoporosis: Can it Be Prevented?

The prevention of post-menopausal osteoporosis is a challenge for primary care physicians. Recently available technology to determine bone density can help determine whether intervention other than dietary calcium recommendations and an exercise program is appropriate. Estrogen replacement therapy can be used for post-menopausal women who have no contra-indications. The use of concomitant progestational agents in a cyclic fashion or with a low-dose continuous regimen reduces the risk of endometrial malignancy. In the future new investigational agents that modulate bone turnover could be recommended.

Anticentromere antibodies--clinical correlates.

We tested 11,594 consecutive sera for antinuclear antibodies and 1,502 were found to be positive; 68 patients (72 sera) had anticentromere antibodies. A retrospective analysis of the clinical characteristics and diagnoses of patients found to have anticentromere antibodies were correlated and showed a diverse array of findings. The association of anticentromere antibodies and the CREST variant of scleroderma may be less specific than originally thought when used as a screening test in an unselected population with rheumatic disease. Anticentromere antibody was present in patients with drug induced lupus, a finding not previously reported.

Cognition in stroke.

INTRODUCTION: Despite the current interest in criteria for vascular dementia, global, as opposed to focal, cognitive change after cerebral infarction has rarely been studied. MATERIAL AND METHODS: We documented the neuropsychological changes one to three weeks and three months post infarct in 25 unselected patients with acute, first cerebral infarcts. RESULTS: Improvements were seen in processes through to have a large subcortical component and in those mediated in the right hemisphere. Memory was relatively lightly affected. CONCLUSION: The minimal deficits seen in memory and the predominance of subcortical changes are at variance with the currently suggested criteria for vascular dementia. Further data of this kind are needed before firm criteria can be proposed for the global pattern of cognitive changes expected in vascular dementia.

Development of an administrative externship in an institution for developmentally disabled.

The development of an administrative externship at an institution for the developmentally disabled is presented. The program utilizes extern rotations through the various departments and units of the institution to provide the students with valuable "hands on" experience in mental health administration. It is suggested that the externship program will serve to increase the number of clinical psychologists with administrative experience and training.

Fundamental importance of arterial oxygen content in the regulation of cerebral blood flow in man.

The relationships between cerebral blood flow (CBF), arterial oxygen content, whole blood viscosity and the transport of oxygen to the brain have been studied in 54 subjects with variations in arterial oxygen content resulting from alterations in haemoglobin concentration ranging from 5.7 to 19.1 g/dl. A highly significant relationship was found between CBF and arterial oxygen content, CBF altering to maintain the rate of transport of oxygen to the brain within certain limits. No significant effect of changes in blood viscosity was evident. In a multiple regression analysis arterial oxygen content emerged as the major determinant of CBF and after this effect had been taken into account there was no significant influence of blood viscosity, arterial pCO2, age or mean arterial blood pressure. The results imply that the alterations in CBF found in subjects with anaemia and polycythaemia are primarily physiological and not caused by the accompanying alterations in blood viscosity. It is proposed that the response of the cerebral circulation to arterial oxygen content is mediated by a local mechanism sensitive to alterations in local tissue oxygen tension.