Neuropathological Problems Arising from Prefrontal Leucotomy

The prefrontal cortex and neurosurgical treatment for intractable OCD

Over the past two decades, circuit-based neurosurgical procedures have gained increasing acceptance as a safe and efficacious approach to the treatment of the intractable obsessive-compulsive disorder (OCD). Lesions and deep brain stimulation (DBS) of the longitudinal corticofugal white matter tracts connecting the prefrontal cortex with the striatum, thalamus, subthalamic nucleus (STN), and brainstem implicate orbitofrontal, medial prefrontal, frontopolar, and ventrolateral cortical networks in the symptoms underlying OCD. The highly parallel distributed nature of these networks may explain the relative lack of adverse effects observed following surgery. Additional pre-post studies of cognitive tasks in more surgical patients are needed to confirm the role of these networks in OCD and to define therapeutic responses to surgical intervention.

Posterior Cuts in Prefrontal Leucotomy: A Clinico-Pathological Study

The usual leucotomy cut in this country, made through burr holes orientated by means of skull measurements, in the majority of cases enters the brain at about the middle of pars triangularis of the inferior frontal gyrus (Brodmann's Area 45), and if performed in a strictly coronal plane remains entirely within the prefrontal region. Intentionally or unintentionally cuts are not infrequently placed either anterior or posterior to this plane. That cuts made posterior to strictly prefrontal levels are often followed by an unfavourable post-operative course distinguished by particularly severe personality change, persisting incontinence, vasomotor, trophic and neurological disturbances has been demonstrated by Knight (1943), Meyer and Beck (1945), Ziegler and Osgood (1945), Reitman (1946) and others.

Anatomical Correlates of Improvement After Leucotomy

Out of 95 leucotomy cases of which the brains and clinical records have been collected at this laboratory, 45 were cases with post-operative survival of over 5 months, and more than 20 of these showed some degree of clinical improvement. Such numbers now make worth while an attempt to ascertain whether or not any attribute common to the lesions is a prerequisite to clinical improvement; whether or not the degree of improvement tends to vary with any qualitative or quantitative feature of the lesions; and whether or not any such relationship between lesions and improvement which is revealed holds good in equal degree for each of the main types of functional-psychosis. Over 20 of the same 45 cases had a recorded post-operative change of personality, so that relationship of post-operative personality change to the leucotomy lesions can conveniently be investigated in the same group of cases. Only some general findings concerning the personality change will, however, be touched on in the present paper.

Some Reflections on the Nature of Affective Disorders, Arising from the Results of Prefrontal Leucotomy

For the use of the term “affective disorder” there is good literary warrant. Shakespeare, writing in the last decade of the sixteenth century, or just before it, uses the word thus:

Clinico-Anatomical Studies of Frontal Lobe Function Based on Leucotomy Material

The present paper is based upon the investigation of 95 brains of patients dying some time after leucotomy, and mainly, though not exclusively, upon the 45 cases in which the survival period was more than 5 months (up to 5 years). In a third of the total material and in about half of the 45 cases with survival longer than 5 months a full microscopical investigation has been carried out or is nearing completion. Eventually all the informative cases will have been so examined, but investigation by serial sections of considerable parts of the brain is a time-consuming undertaking. An unfortunately irremediable defect in our material is the unevenness and incompleteness of the clinical, physiological and psychological investigations of the patients. Obviously only limited correlation studies can be carried out on such material. Again, the number of fully recovered cases in our material is small, in fact only some four (Nos. 66, 71, 10 and 18) of the total could be classed as such. The reason for this is that fully recovered patients are likely to die from intercurrent disease outside mental hospitals, when it is difficult to procure a post-mortem.

Frontal Lobe Function and the African

In a previous article—” A Study of Mental Derangement in Africans “—the writer described primitive African culture, thinking and attitude to life, and the types of mental derangement seen in Kenya over a 5-year period, and endeavoured to explain the peculiarities in the incidence and nature of African mental derangement on the basis of cultural factors.

The Results of Prefrontal Leucotomy in 68 Patients Not Discharged from Hospital

The 68 patients surveyed in this paper form a companion group to the equal number who have been discharged from hospital and of whom a follow-up study has been published by Frankl and Mayer-Gross (1947). The patients' condition was studied during the early months of 1947, when they had remained in hospital from 1 to 4 years after operation or had returned after an unsuccessful attempt at discharge. To what extent they have to be considered as failures will be seen in the paper. They are of special interest not only as a contrast to the more successfully treated patients, but also because a closer observation of the course of their illness was possible than with the discharged group. Being under constant clinical observation since the operation, all significant changes in their condition have been recorded and the important problem of relapse, neglected in the large literature on leucotomy, can be discussed on the basis of these observations. Finally, an answer was sought to the question of why these patients should have reacted less favourably to the operation than their fellows.

Telencephalon: Neocortex

The neocortex is an ultracomplex, six-layered structure that develops from the dorsal palliai sector of the telencephalic hemispheres (Figs. 2.24, 2.25, 11.1). All mammals, including monotremes and marsupials, possess a neocortex, but in reptiles, i.e. the ancestors of mammals, only a three-layered neocortical primordium is present [509, 511]. The term neocortex refers to its late phylogenetic appearance, in comparison to the “palaeocortical” olfactory cortex and the “archicortical” hippocampal cortex, both of which are present in all amniotes [509].

Tract identification by novel MRI signal changes following stereotactic anterior capsulotomy

BACKGROUND

Five patients underwent magnetic resonance imaging (MRI) following MRI-guided stereotactic bilateral anterior capsulotomy to detect lesion-related anatomic changes.

METHODS

Five disabled and treatment-resistant patients with major depression (n = 4) and obsessive-compulsive disorder (n = 1) underwent stereotactic bilateral anterior capsulotomy. All patients had postoperative MRI at 2 months and at 1-4 years after surgery. An additional patient who had a pure motor deficit following a spontaneous basal ganglia hemorrhagic stroke was imaged as a comparator.

RESULTS

The 2-month postcapsulotomy MRI showed a previously undescribed increase in T1-weighted signal within similar neural pathways for each patient. These pathways showed no changes in T2-weighted or fluid-attenuated inversion recovery sequences. The signal changes are different from the expected changes associated with anterograde Wallerian degeneration and identify retrograde changes in the proximal segment of the interrupted axon.

CONCLUSION

Previously undescribed T1-weighted signal alterations following stereotactic surgery identify retrograde non-Wallerian changes in interrupted axons and provide a new method in identifying and tracing lesioned pathways.

Failed leucotomy with misplaced cuts: a clinico-anatomical study of two cases

Failure of treatment does not necessarily mean inappropriate treatment; it must first be ascertained that the treatment has been carried out. Increasing attention is being paid to this question in regard to drug therapy with estimations of blood and urine levels. Patients who fail to get better after leucotomy may have been unsuitably chosen; they may also fail to get better because the aim of the operation, namely to sever the thalamo-frontal radiations, has not been achieved. Neuro-anatomical studies have long suggested that not only do many patients remain with these tracts intact following a blind operative approach but that there is also great variability in the size and position of the lesions produced, a consequence of unreliable surface markings, brain fibre elasticity, complicating haemorrhages and progressive gliosis. The blind approach is no ideal surgical method, since it results in a largely fortuitous lesion (Meyer and McLardy, 1948, 1949; Beck, McLardy, and Meyer, 1950; Eie, 1954; Meyer and Beck, 1954). There is even a gross discrepancy between the actual and desired point of insertion of the leucotome (Dax, 1943). Whilst the effects of misplaced cuts have been studied by these workers, one can only guess what proportion of clinical failures can be attributed to misplaced cuts and what proportion of successes follow misplaced cuts (Meyer and Beck, 1954). Appeals for further studies with post-mortem correlates have been made by these authors.

Bi-frontal stereotactic tractotomy: an atraumatic operation of value in the treatment of intractable psychoneurosis

Stereotactic surgery has provided a means of producing accurate lesions at selected points in the nervous system where concentrations of nerve cells or fibre pathways possessing specific functions permit some small area of anatomical destruction to produce widespread physiological effects. The value of this method in relation to motor and sensory activity is illustrated by the results of thalamotomy in the treatment of Parkinsonian tremor and by stereotactic division of the spinothalamic tract in the cervical cord for the relief of incurable pain. The accuracy of approach and minimal disturbance of tissue ensures that the beneficial effects of these operations are produced in isolation without associated disfunction in the nervous system. That a similar principle can be applied in relation to the control of emotion has been shown in cases of intractable psychoneurosis treated by the operation of bifrontal stereotactic tractotomy in the substantia innominata (Knight, 1964). Owing to the influence of emotion in psychoneurotic states it is possible to influence many syndromes satisfactorily by operation at a site where connections of the limbic system concerned with instinctive and emotional activity rather than cognitive processes converge to a point beneath the head of the caudate nucleus, thereby producing a reduction in the intensity of emotional reaction without undesirable personality change or post-operative epilepsy. It is felt that it would be useful to summarize the anatomical features in order that the differences between this operation and the old leucotomy procedure can be generally appreciated. It is particularly among cases of chronic and recurrent depression that this form of surgery can be most usefully employed.

STEREOTACTIC TRACTOTOMY IN THE SURGICAL TREATMENT OF MENTAL ILLNESS

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