Cranial computerized tomography in clinical psychiatry: 100 Consecutive cases

Cranial Computerized Tomography in Clinical Psychiatry: 100 Consecutive Cases N. J. f?. Evans

INTRODUCTION

C

OMPUTERIZED tomography has in a short time established itself in clinical neurology and neurosurgery. In psychiatry its reported use is mainly as a research tool. In particular, attention has been directed towards the relationship between dementia and the appearances of cerebral atrophy, and the findings of atrophy, perhaps unilateral or local, in schizophrenics or subgroups of schizophrenics. Suggestions for its clinical diagnostic use are given by Oxman,’ who also tabulates estimates of its accuracy in various neurological disorders from published sources. More recently a series’ of patients with organic brain syndrome who had both CT and Radionuclide Scans indicated the superiority of CT as a screening test in this condition, and another series3 of dementia patients illustrated that pneumoencephalography has virtually been replaced by CT. However, series of general psychiatric patients seem lacking, although increasing numbers of psychiatric patients from clinical practice are being referred for a CT scan. This paper reports experience in this regional teaching centre. The service was established on its present footing in January 1978 with an EMI 1010 instrument in New Addenbrooke’s Hospital for National Health Service referrals from the whole of the East Anglian Region, which has an area of 5,000 square miles and a population of about 1.9 million. During the first 24 years up to the end of June 1980, the period of this survey, nearly 7,500 patients were scanned, many of them of course more than once. METHOD The material was restricted to patients referred by psychiatrists working in Cambridge, because it might be expected that the expense and inconvenience of sending patients from further away (up to 80 miles away in this Region) would result in a specially selected group. The subjects were identified from the records of the CT Department by the name of the consultant making the referral. In this way only those referred directly by psychiatrists were collected. Patients who might have initially presented psychiatrically but had been taken over, by for example a neurologist, were excluded. The first 100 consective cases were collected, including both outpatients and inpatients. Details of history, mental state, physical findings and psychiatric diagnosis were obtained from the CT request forms and the case notes. and are those recorded by the clinicians concerned. The patients were then classified in three groups on a hierarchical basis.

From Department of Psychiatr?, University of Cambridge, Cambridge, England N. J. R. Evans M.A. B.M. B.Ch. MRC Psych. Research Associate Address reprint requests to N. J. R. Evans, Department ofPsychiatr?/ University of Cambridge. Cambridge, England 0 1982 by Grune & Stratton. Iyc. OOlO-440X/821230Sl0007$1.0010 Comprehensive

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(i) organic: those with features in the mental state such as clouding of consciousness, impaired memory, intellectual deterioration; (ii) neurological: those with signs in the central nervous system, or neurological symptoms, in addition to their psychological disturbance; (iii) functional: those with psychological disturbance alone. The CT finding are the consultant radiologists’ reports.

RESULTS 1. Referral Rate. Psychiatric patients were not referred in large numbers: one hundred out of the first 7,500 were from this source although there was a trend to increasing frequency of referral. The excluded psychiatric patients from outside the Cambridge area were far fewer in number. 2. Age of Patients (summarized in Table 1). On the whole this is a fairly old group, weighted by the numbers with dementia and other organic psychiatric states. The neurological and functional patients are more scattered through the age range, but few young patients were referred. 3. Psychiatric Diagnosis (see Table 2). Nearly half (47) of the patients fell into the oganic group and 30 of these had a clinical diagnosis of dementia; 12 of the rest had acute confusional states and one patient had been referred because of a clinical frontal lobe syndrome. The most common neurological symptom was fits. The commonest functional diagnosis was schizophrenia, which heading includes psychoses described as atypical, paranoid or non-affective. Hysteria, considered by Slater4 a snare and a delusion on account of latent neurological disorder, was the diagnosis in only two patients. 4. C.T. Findings (see Table 2). Radiological cerebral atrophy was a common finding (66), but especially in the organic patients. The next most common finding was normal appearances (24), and the number of patients in whom specific lesions were detected was only 8, of whom 2 had tumours. Two scans had to be abandoned at an inconclusive stage because the patients were unable to co-operate. DISCUSSION The purpose of performing a cranial CT scan in psychiatry, as in the rest of clinical medicine, is to confirm or exclude an intra-cranial lesion as the cause of the patient’s symptoms and signs. It is well known that such lesions can present psychiatrically, and indeed it is something of a pre-occupation that they may be missed. The problem is that a symptomatic psychosis may Table 1. Mean Ages and Clinical Diagnosis (4 Males Organic Dementia Other Neurological Functional All patients All non-demented

patients

(20) (13) (7) (12) (20) (52) (39)

67.4 71.8 59.3 49.8 49.1 56.3 51 .I

Females (27) (16) (11) (91 (12) (48) (32)

66.4 69.2 63.2 46.3 42.4 56.8 50.7

TOMOGRAPHY

IN CLINICAL

Table 2. Diagnostic Organic

47

Alcoholic Frontal 21

Groups

Dementia

Confusional

Neurological

447

PSYCHIATRY

State

Brain Damage Lobe Syndrome

Epilepsy

CNS Signs

Functional

32

and C T Findings 30

Atrophy Subdural Haematoma Major Infarction

12

Atrophy Normal (abandoned

8 3

4

Atrophy

4

1

Normal

1

11

Atrophy Arachnoid Cyst Astrocytoma Normal

5 1 1 4

8

Atrophy Pituitary Tumour Major Infarction Normal

1

5 1

Vertigo

1

Atrophy

Losses of Consciousness

1

Major

Schizophrenia

etc.

19

7

Atrophy Normal

Anxiety

2

Atrophy Normal

State

Hysteria

Personality

Disorder

1)

1 1

1

Infarction

Atrophy Normal (abandoned

Depression

27 2 1

11 7 1) 6 1 1 1

2

Atrophy Normal

1 1

2

Atrophy Normal

1 1

be clinically indistinguishable from a primary one,5.h or a symptomatic dementia may have no features which clearly set it apart from the great mass of dementias of Alzheimer type. Resources are limited and it is no more possible to scan every psychiatric patient than every patient who attends the neurology clinic. How does one decide which patients should be intensively investigated? Reasons for referral It proved hard to assess in retrospect why the clinicians had selected many of these patients. Among the dements age was probably a factor; their average age of about 70 is low for dements seen by psychiatrists, and a number were clearly of presenile onset. In view of the seriousness and hopelessness of the diagnosis of Alzheimer’s Disease, these younger patients are conventionally

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N. J. R. EVANS

more fully investigated than the very old, although there is no evidence that the proportion with specific lesions or treatable causes of dementia diminishes with age. The patients who had neurological signs or symptoms were a more heterogeneous group, and many of them had been psychiatrically ill for years before neurological features emerged or were detected. A 48 year old West Indian was admitted as an emergency. He had attracted notice by standing in a supermarket for some hours, muttering nonsense and performing various ritualistic activities. Independent information revealed that he had been known in the neighbourhood for strange behaviour over a number of years, and his life had gradually become completely disorganised. He had acromegalic features and visual field defects and the CT scan showed a pituitary tumour.

Late-onset

epilepsy obviously

arouses suspicion of a tumour.

A woman of 70 was referred to the psychogeriatric clinic because of depression with anorexia and apathy. By the time she attended she was having minor focal fits. On the scan there was a large posterior parietal turnout-, probably an astrocytoma.

Many of the functional patients were in their first illness and this was frequently described as being unusual, atypical, or having “organic features”; often it was implied that it was surprising that a particular patient had become pyschiatrically ill, there being no predisposition such as heredity, and no obvious precipitant: could an extraneous organic event explain the discontinuity in mental life? The table shows that in this small sample the expectation was not fulfilled. The signi$cance

of cerbral atrophy

Cerebral atrophy in this context means the radiological appearance of enlarged C.S.F. spaces. There is a large body of literature describing investigations of the relationship between radiological atrophy and dementia; there is a smaller amount of information on the changes in appearance in normal aging. While it is possible that automated methods of processing CT data may yet add to knowledge of the diseases, at present its clinical diagnostic value in the individual case of dementia is severely limited because of the overlap in atrophic appearances between demented and non-demented groups. Jacoby and Levy7 have recently reviewed the CT studies, and the position is roughly the same as had been arrived at with air encephalography, and is predictable from neuropathology .8*9Reports of atrophy in schizophrenics, again a replication of earlier air studies, have so far been inconclusive,” although the redefinition of subgroups” may progress from this. As part of their carefully controlled studies of elderly patients, Jacoby and Levy” also find certain correlations between atrophy and affective illness. No measurements were available in the present survey which relies on radiological judgment, and is uncontrolled, and does not examine the quantitative problem. However, the finding that several of the younger functional patients were reported to show cerebral atrophy conforms with some of the observations and reflects the old controversy.

TOMOGRAPHY

IN CLINICAL

PSYCHIATRY

449

The effect on management When a service has to be limited the usual method of “vetting” requests is to ask what are the chances of a positive result and what would be its effect on management. The finding of a treatable lesion in a patient whose prospects otherwise are custodial care for dementia or long-term drug therapy for psychosis would patently change management completely; missing it might increase morbidity and shorten life. The value of excluding a major diagnostic possibility must be reckoned. I3 In this series there were no therapeutic successes: the two elderly patients with subdural haematoma had been demented for several years and were not operated on; treatment of the pituitary tumour mentioned above did not relieve the patient’s psychosis; the patient with an astrocytoma died shortly after consultation. On the other hand an adverse effect on a patient’s management may result from misinterpretation of the significance of atrophy. A widow of 70 presented with rapid cognitive failure. In the past she had several bouts of typical depressive illness which responded well to ECT or antidepressant drugs. When atrophy was demonstrated treatment was delayed. but some spontaneous improvement occurred. and after ECT her cognitive functions returned to normal for her age.

At present, CT is unable to help in differentiating depression from dementia. The yield of useful results in this series may appear disappointing, and ordinary clinical work with CT is still rooted in identifying abnormal structure rather than moving on to Images of Brain Function,‘4 but for the future it may at least be hoped that experience with CT will elucidate some of the ancient problems of symptomatic psychoses, and long-term follow-up of larger numbers of patients than was possible when air encephalography was required to show enlargement of the C.S.F. spaces may contribute to knowledge of the aetiology of a variety of apparently functional disorders. SUMMARY Many psychiatric patients require neurological investigation and some are referred for computerized tomography. The results in a consecutive series from clinical practice in the English National Health Service are reported here, with discussion of some of the problems of selecting cases for this necessarily restricted facility. ACKNOWLEDGMENTS I am grateful to Dr. G.E. Berrios, Dr. T.D. Hawkins and Sir Martin Roth for discussion this work which is supported by an M.R.C. Grant to Professor Roth.

of

REFERENCES I. Oxman TW: The Use of Computerized Axial Tomography in Neuroradiologic Diagnosis in Psychiatry. Comprehensive Psychiatry 20:177-186, 1979 2. Tsai L. Tsuang MT: Relative Efficacy of Computed Tomography and Radionuclide Scan in the Diagnosis of Organic Brain Syndrome. Biol Psychiatry 15:14I-145, 1980

3. Smith JS. Kiloh LG: The Investigation of Dementia: Results in 200 Consecutive Admissions. Lancet i:824-827, 1981 4. Slater E: Diagnosis of “Hysteria”. British Medical Journal 1:139.5-1399. 1965 5. Davison K, Bagley CR: Schizophrenia-like psychoses associated with organic disorders of the central nervous system: a review of the

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literature, in Herrington RN (eds): Current Problems in Nemopsychiatry. British Journal of Psychiatry Special Publications No. 4. Ashford, Headley Brothers, 1969 6. Lishman WA: Organic Psychiatry. Oxford, Blackwell Scientific Publications, 1978, pp 176-178 7. Jacoby R, Levy R: CT scanning and the investigation of dementia: a review. Journal of the Royal Society of Medicine 73:366-369, 1980 8. Tomlinson BE, Blessed G, Roth M: Observations on the brains of non-demented old people. Journal of Neurological Science 7:331-356, 1968 9. Tomlinson BE, Blessed G, Roth M: Observations on the brains of demented old peo-

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ple. Journal of Neurological Science 11:205-242, 1970 10. Lancet Editorial: Scizophrenia and cerebral atrophy. i:858-859, 1980 11.Johnstone EC, Crow TJ, Frith CD, et al: The dementia of dementia praecox. Acta Psychiatrica Scandinavica 57:305-324, 1978 12. Jacob RJ, Levy R: Computed Tomography in the Elderly. 3. Affective Disorder. British Journal of Psychiatry 136:270-275,198O 13. McNeil BJ, Hanley J, Funkenstein HH, et al: Utilization of Computed Tomography of the Head in a Tertiary Care Hospital. Radiology 139:113-118, 1981 14. Lancet Editorial: Images of Brain Function. ii:725-726, 1979