Russell Meyers

Determination of topologic human brain representations and modifications of signs and symptoms of some neurologic disorders by the use of high level ultrasound

THOSE ASPECTS of high intensity, focused ultrasound which make it especially useful for elucidating and inducing changes in brain mechanisms subtending certain neurologic disorders and thus for modifying their clinical manifestations have resulted from extensive experimental animal studies carried out during the past decade by several of us (Messrs. Fry and associates). These studies, making use of precisely controlled dosages of ultrasound, have led to several initial discoveries and published reports that may be synopsized as follows: 13 Permanent lesions of arbitrarily predetermined size, shape, and orientation can be produced at any site(s) in the brain. No disruption of intervening tissue is thereby entailed.’-5 21 Changes in function of the tissues can be achieved by suitable modification of the Farameters of irradiation. Such changes can be both short-lived (“reversible”) and enduring (“irreversible”) .6 The reversible changes need not be attended by histologically identifiable lesions.?-10 Here again, intervening tissues regularly escape demonstrable disruption. 31 The vascular system can be left anatomically intact and functioning in cerebral regions in which all neuronal elements (neurocytes and/or their fiber processes) are destroyed.*JJl 41 Fiber tracts of white matter can be interrupted without damage to neighboring or surrounding gray matter that receives an equal dose of ultrasound.’,3.5,”.’” 51 Mortality and morbidity are extremely small if brain structures not directly involved in mediating vital functions and the responsive state (“consciousness”) are not irradiated to produce enduring changes. 61 Evidence thus far obtained indicates that cumulative effects (comparable, for example, to those induced by x-rays and high energy particle radiation) are not produced. 71 Strong presumptive histologic evidence is at hand to indicate that differential susceptibilities to ultrasound exist, in addition to those cited in items 3 and 4. With appropriate choice of the parameters of irradiation, myelin sheaths appear more vulnerable than axis cylinders. In consequence of these disclosures, it appeared feasible to employ ultrasonic procedures for investigating and modifying the mechanisms underlying certain neurologic disorders in man. Accordingly, we performed during the past one and one-half years 46 ultrasonic irradiation procedures on 41 patients. The disorders to which our attention has been directed are: Hyperkinesia, the patterned tremors in park-

The surgical treatment of focal epilepsy: an inquiry into current premises, their implementation and the criteria employed in reporting results.

The purpose of this paper is three-fold: ( 1 ) to record the generally disappointing character of results obtained in the author’s series of cases of “focal” epilepsy subjected during a fifteen year period to extirpation of cortical regions regarded as epileptogenous zones; (2 ) to inquire into the validity of certain current premises upon which the rationale of such operations appears to rest, with a view to pointing up some theoretic and practical reasons responsible for surgical failures; and (3) to examine the circumstances under which the terms “cured”, “arrested“, “controlled”, “improved“, “successful”, etc., as generally employed in the evaluation of clinical results, may properly be applied in future reports.

An Early Description of the Gerstmann Syndrome

IN 1924 Josef Gerstmann described “finger agnosia,” an apparently hitherto unrecognized behavioral deficit appearing as a consequence of cerebral disease.l In this and subsequent papers, he called attention to the frequent association of finger agnosia with right-left disorientation, dyscalculia, and d y ~ g r a p h i a . ~ ~ ~ His observations were soon confirmed by other investigators, and the tetrad of symptoms has come to be known as the Gerstmann syndrome. While right-left disorientation, dyscalculia, and dysgraphia were phenomena that had long been familiar to clinicians, it is generally believed that finger agnosia, that is, the inability to localize fingers subjected to tactual stimulation or to name or otherwise indicate them upon verbal command, was not known before the appearance of Gerstmann’s communication. This impression is not altogether correct. In 1888 the French ophthalmologist, Jules Badal, published a detailed case report4 describing a female patient who, during a considerable period of study following severe eclampsia characterized by edema, convulsions, coma, and anemia, showed a variety of behavioral deficits including finger agnosia and the other elements of the Gerstmann syndrome. Other deficits, sometimes considered to be associated with the syndrome, such as constructional apraxia and spatial and temporal disorientation, were also present. Badal’s case report was evidently not unknown to neurologists 50 years ago. In a monograph published in 1898 Pick quoted rather extensively from it, and in a communication ten years later he referred to it as “the well known case of Badal.”jV6 However, this early contribution appears to have been overlooked in recent years, for it is not mentioned in the reasonably complete historical surveys included in current mon~graphs.~-l~ Hence, it seems worthwhile to recall attention to this once “well known” case report, both as a matter of intrinsic historical interest and because it poses a problem which is still unsettled.

Intracerebral metastatic granular cell myoblastoma.

The purpose of this paper is to communicate the essential clinical and pathological features of a case in which a granular cell myoblastoma was encountered in the brain. The tumor in this instance represents a metastasis, the source of which was probably a histologically similar neoplasm in the right biceps femoris muscle. A review of the literature discloses no case in which this relatively uncommon tumor has occurred intracranially.