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J R Bartlett

Publications and source records attributed to J R Bartlett.

At least 19 recordsLinked to original sources

Depression: a role for neurosurgery?

After providing an overview of depression this article briefly reviews the development of psychosurgery and outlines the current procedures in use world wide. Stereotactic subcaudate tractotomy (SST) is described in particular detail, and the rationale for its use in the treatment of resistant depression is then discussed by considering the findings of neuropsychological, neurophysiological and neuroimaging studies. The emerging evidence suggests that the prefrontal cortex subserves an essential function in emotion and that disruption of its connections modifies mood.

Depressive Disorder↗

Visual prognostic value of the pattern electroretinogram in chiasmal compression.

BACKGROUND/AIMS: The visual loss associated with compression of the optic chiasm by pituitary tumours may be transient or permanent, possibly related to the extent of irreversible retrograde degeneration to the retinal ganglion cells. The pattern electroretinogram (PERG) N95 component is thought to rise in relation to retinal ganglion cell function and hence may be a potential prognostic indicator for visual function following decompressive surgery. METHODS: The notes and electrodiagnostic records of 72 eyes from 36 patients with chiasmal compression were retrospectively analysed. RESULTS: The postoperative change in visual field was found to be associated with the PERG N95:P50 ratio (p=0.01). Improvement in visual field was shown by a greater proportion of eyes with a normal N95:P50 ratio (65%) than with an abnormal ratio (27%). No change in visual field occurred in 26% of the eyes with a normal N95:P50 ratio compared with 67% of those with an abnormal ratio. Only 8% of eyes showed a worsening of visual field following surgery, in similar proportions for eyes with normal and abnormal N95:P50 ratios. There was no significant relationship with visual acuity. CONCLUSION: The PERG is a useful visual prognostic indicator in the preoperative assessment of chiasmal compression.

Adult↗

Intrapituitary fluid levels following haemorrhage: MRI appearances in 13 cases.

Demonstration of fluid levels on MRI is well recognised in cerebral haematomas, tumours and cysts. The occurrence of fluid levels within haemorrhagic pituitary tumours has not previously been described in detail. Evidence of haemorrhage was identified in 27 of 125 pituitary tumours. Fluid levels occurred in 13 of these haemorrhagic tumours. No association with histological type was identified. Recognised risk factors for haemorrhage were identified in half of the cases.

Adenoma↗

Spinal meningiomas: a 20-year review.

The long-term outcome of 78 patients with spinal meningiomas operated on over 20 years at a single neurosurgical unit was analysed. Age, sex and tumour location were similar to those reported by others. Overall, 95% of our patents were independently mobile postoperatively, despite 25% of the group being unable to walk before operation, including four paraplegic patients. Only two tumours were entirely extradural, and a further two were both intra- and extradural. In all cases, tumour exposure was by posterior laminectomy, without recourse to more complex approaches. Complete tumour resection was achieved in 77 (98%) of cases. The dural attachment was excised in 20 cases and diathermy was applied in 58. There was one recurrence, 14 years after the original surgery. Complex and technically challenging surgical approaches are unnecessary to obtain complete removal even for anteriorly placed tumours. Excision of the dural base would seem unnecessary to attain a low recurrence rate.

Adult↗

Prediction of outcome in severe head injury based on recognition of sleep related activity in the polygraphic electroencephalogram.

This study shows that the continuing presence of activity similar to normal sleep in the EEG in conjunction with the EEG polygraph (EEGP) can be used to determine the severity of brain damage after head injury. Recordings were taken within seven days of head injury from 154 unselected patients after resuscitation and emergency surgery. Sixteen patients with ongoing seizures were excluded. In the remaining 138 patients the presence of activity in the EEG, EEGP, or both, which can also be recognised in normal alertness and sleep, was noted. Particular attention was paid to the presence or absence of arousal related phasic activity involving EEG, motor, and autonomic changes. The traces were allocated to one of five groups: group 1, wakeful traces with normal alpha in at least one hemisphere; group 2, sleep-like traces with K complexes responsive to stimulation; group 3, traces with phasic activity related to abnormal spontaneous arousal including EEG changes; group 4, traces with abnormal spontaneous arousal activity without EEG changes; group 5, traces with no spontaneous arousal activity. The mean follow up was 21.5 months. Groups 2 and 3 were significantly associated with a good outcome and group 5 with death or a vegetative state. Comparison between the EEG/EEGP findings and the Glasgow coma scale at the time of the recording showed the EEG/EEGP to be the better predictor of outcome, particularly for individual patients.

Adolescent↗

Outcome after the psychosurgical operation of stereotactic subcaudate tractotomy, 1979-1991.

The outcome of all psychosurgical operations (stereotactic subcaudate tractotomies) performed at the Geoffrey Knight National Unit for Affective Disorders in London since 1979 is reviewed. Of patients who had suffered severe mood or obsessive-compulsive disorders before surgery, 84 of 249 (34%) were well 1 year after. The effects of gender, psychiatric diagnosis, and age on outcome are assessed. The findings are compared with a 1975 outcome study, and explanations for apparent differences are proposed.

Adult↗

Psychosurgery: stereotactic subcaudate tractomy. An indispensable treatment.

BACKGROUND: Stereotactic subcaudate tractotomy (SST) is the only type of psychosurgery performed at the Geoffrey Knight Unit, London, where nearly 1300 operations have been done since 1961. Statistically reliable data are not available to prove the effectiveness of SST. A detailed statement about contemporary psychosurgery is given. METHOD: Relevant publications from the Unit and via Medline are discussed. The outcome figures are reviewed. The outcome is assessed at the Unit in global and clinical terms, associated with results of self-completed questionnaires. RESULTS: SST allows 40-60% of patients to live normal or near-normal lives, perhaps with continuation of medication. A reduction in suicide rate to 1% post-operatively, from 15% in cases of uncontrolled affective disorders is seen. CONCLUSION: As a treatment of last resort, no controlled trial against a comparable treatment is possible. It appears reasonable to offer SST to patients with suicidal and deluded depression or with frequently swinging moods, not responding to other treatments.

Adult↗

Antemortem measurements of neurotransmission: possible implications for pharmacotherapy of Alzheimer's disease and depression.

Aspartic acid, 5-hydroxyindoleacetic acid, glutamic acid, homovanillic acid and 3-methoxy-4-hydroxyphenylethylene glycol was determined in samples of ventricular fluid from 82 subjects. Laminar distribution of the total number (Bmax value) of serotonin 1A receptors was determined on seven neurosurgical samples of neocortex. Apart from an association in a small subgroup of subjects between homovanillate concentration and corticosteroid medication, no complicating influences of treatment preceding operation were found. The content of the serotonin metabolite alone was significantly reduced in intractable depressive illness (bipolar and major depressive disorders) compared with neurological conditions subdivided into Alzheimer's disease, other dementias and other conditions. There was no other significant difference between these groups for the compounds measured. The total number of serotonin 1A receptors was highest in the superficial layers, being considerably higher than in the rat, irrespective of cortical layer. This part of the study indicated that these receptors are important for regulating activity of human corticocortical glutamatergic neurons. The results are discussed in relation to treating depression with serotonergic agents and targeting corticocortical glutamatergic neurons as well as acetylcholine in Alzheimer's disease.

Adult↗

Effect of psychotropic drugs on excitatory amino acids in patients undergoing psychosurgery for depression.

Samples of ventricular CSF were taken from 52 consecutive patients admitted for psychosurgery for intractable depression. Concentrations of asparagine, aspartate, glutamine, glutamic acid, and serine were determined. Glutamate and aspartate concentrations, implicated in excitotoxic brain damage, were not affected by various types of psychotropic drug treatment. Serine, a modulator of glutamate responses, was significantly elevated in samples from subjects receiving antidepressants. These subjects responded poorly to the operation. Psychotropic drugs are unlikely to be neurotoxic. Nevertheless, antidepressants may influence excitatory neurotransmission.

Adult↗

Neuropsychological correlates of stereotactic subcaudate tractotomy. A prospective study.

Stereotactic subcaudate tractotomy is a surgical procedure performed for the alleviation of intractable affective disorders. It involves the destruction of bifrontal pathways located beneath and in front of the head of the caudate nucleus. We report the first prospective study of the neuropsychological correlates of this operation in 23 patients. Tests of general intelligence, speed and attention, as well as a wide range of focal cognitive tests, including tasks which have been reported in the literature to be sensitive to frontal lobe dysfunction, were administered 1 wk before the operation, 2 wks after the operation and approximately 6 mths after the operation. The results indicated that this operation does not cause any significant, long-term adverse, cognitive deficits. In the post-operative assessment, however, patients show a significant deterioration in their performance on recognition memory tests and a large proportion of them present with a marked tendency to confabulate on recall tasks. In addition, their performance on some of the tasks which are considered to be sensitive to frontal lobe dysfunction is found to be significantly impaired. These deficits are interpreted to reflect frontal lobe dysfunction due to widespread post-operative oedema rather than damage to the subcaudate pathways. The potential for research on these transient effects of the operation for the advancement of our understanding of frontal lobe functions is discussed.

Adult↗

Brain amino acid concentrations and Ca2+-dependent release in intractable depression assessed antemortem.

The concentrations of 3 putative neurotransmitters (glutamate, aspartate and gamma-aminobutyrate), 4 related amino acids and 5 non-transmitter-related amino acids have been measured in neurosurgical samples (frontal cortex) from patients with intractable depression and controls. In addition, the glutamate receptor agonist 2-amino-4-sulpho-butanoic acid (homocysteic acid) has been identified in human brain and measured in these samples. There were no changes in the concentrations of amino acids in depressed patients compared to control with the exception of aspartic and homocysteic acids which were elevated in a sub-group of patients with depression compared to control. The Ca2+-dependent release (K+-stimulated) of putative neurotransmitters has been demonstrated for the first time from brain tissue of depressed patients. Glutamate release was unaltered from the control value. Aspartate values showed unexplained variability but it's release and that of gamma-aminobutyrate were elevated in some depressed subjects. These results do not support the hypothesis of reduced amino acid function in depressive illness.

Aged↗

Amino acid levels in depression: a preliminary investigation.

Plasma, cerebrospinal fluid and brain tissue amino acid levels were measured in 14 patients with affective illness and generally confirm previous findings. There was no correlation between these values and age, sex, family history and levels of anxiety. GABA levels measured in cortex tissue were negatively correlated with depressive mood (P less than 0.05), supporting a possible involvement of GABA in depressive illness.

Adult↗

Resistant bipolar affective disorder treated by stereotactic subcaudate tractotomy.

The results of stereotactic subcaudate tractotomy in nine patients with resistant bipolar affective disorder are presented in the form of a single case study with a summary of the other eight cases. Follow-up studies at 2-4 years showed substantial improvement in five patients and amelioration of symptoms in a further four patients, with a tendency for a greater improvement in the manic than in the depressive episodes. These preliminary results suggest that there is a place for this operation in the management of severe bipolar affective disorders which are not responding to any other treatment, although decisive recovery occurs less often than with unipolar depression.

Bipolar Disorder↗

Psychosurgery in Britain now.

Between 1979 and 1986 the number of psychosurgical operations carried out in Britain fell from 70 to 15 procedures annually. There are a number of possible reasons for this change of which increased experience with new regimes of psychotropic medication is perhaps the most important. The new Mental Health Act (1983) which brought psychosurgery under the direct jurisdiction of the law was followed by a sudden reduction in the number of patients treated but referals are now increasing. In current psychiatric practice, classification relies largely on description of syndromes, each characterised by a set of core symptoms. Schizophrenia and affective psychoses (endogenous depression, mania and obsessional illness of late onset) are characterised by disturbances of mood, thinking and perception often so profound as to impair the patient's contact with reality. In contrast, neuroses produce symptoms which are quantitatively, rather than qualitatively different from normal experience and psychosurgery has no place in their treatment. Following the introduction of phenothiazines in the early 1950's schizophrenia ceased to be an indication for psychosurgery. For a small group of severely disabled and distressed people suffering from endogenous depressive and obsessional illnesses, when other treatments have failed or ceased to be effective, psychosurgery remains an appropriate treatment. Just over half the patients treated at the Geoffrey Knight Unit are relieved to the extent that they are either free of symptoms or such symptoms that remain do not significantly impair social function. Following operation recovery is slow and progressive and a programme of rehabilitation is usually necessary. Personality which is often severely damaged by the effects of long illness returns towards normal. Neuropsychiatric evaluation has consistently failed to demonstrate adverse cognitive effects. Evaluation and selection of patients for operation should be done by a psychiatrist and neurosurgeon working in partnership. Stereotactic techniques have made it possible to produce precisely located lesions of consistent size, virtually eliminating side effects and reducing the epileptic risk to between two and three percent. The Mental Health Act, contrary to early expectations, has allowed that psychosurgery retains a place in the treatment of a small highly selected group of patients.

Humans↗

The stalemate position.

The psychosurgical operation of stereotactic subcaudate tractotomy can be a highly effective treatment for chronic and intractable affective disorders. We have lately given increasing attention to cases where the depressed mood appears to lift although there is little improvement in social function. In these cases there has been a failure of rehabilitation and the complexities of this process post-operatively are discussed. In addition, relatives report in some 10% of cases "personality changes" after the operation which are not perceived in this way by an independent medical assessor and these observations seem to depend upon relatives mis-interpreting the resumption of pre-morbid personality function after long illnesses as undesirable side-effects. Case histories illustrating the problems are described. Treatment and rehabilitation strategies are outlined.

Depressive Disorder↗

Ventricular size and CSF transmitter metabolite concentrations in severe endogenous depression.

The relationship between neurotransmitter metabolite concentrations and measurements of ventricular size on CAT scans and pneumoencephalographs was investigated in 15 patients with severe affective disorder. An association was identified between reduced levels of plasma free tryptophan and ventricular enlargement, and also between raised ventricular CSF levels of 5 HIAA and ventricular enlargement.

Adult↗