Earlier reports have suggested that low-dose ionizing irradiation might be involved in induction of intracranial meningiomas. One of the problems in evaluating irradiation-induced neoplasms is the belief that these tumors have no distinguishing features to indicate their etiology. In an attempt to identify such features in meningiomas following irradiation, a group of 42 post-irradiation meningiomas (PIM's) has been compared with a group of 84 non-PIM control meningiomas. These 42 PIM's included all the intracranial meningiomas diagnosed at the Hadassah University Hospital during the years 1952 to 1981 in individuals treated in childhood with low-dose x-ray therapy for tinea capitis. Although the individual PIM does not seem to differ from a "spontaneous" meningioma, this study indicates that PIM's as a group have distinct characteristics, namely, their location at the site of maximal irradiation, and features suggesting rapid growth and aggressive biological behavior. There was a significantly higher number of calvarial tumors (p less than 0.001), a high proportion of multiple meningiomas, a higher recurrence rate following apparent complete excision (p less than 0.02), and an increased number of histologically malignant meningiomas (p less than 0.01). The demonstration of features that distinguish PIM's from meningiomas of other etiology supports the suggestion that low-dose ionizing irradiation was involved in the pathogenesis of these tumors.

SUMMARY Eighty-nine cases of brain abscess, diagnosed over a period of 30 years, are reviewed. The incidence of this disease did not decline throughout the period. Abscesses of ear and nose origin constituted the largest group (38%). Postoperative abscesses seem to have increased in incidence, presumably due to routine postoperative antibiotic treatment. Antibiotics were possibly responsible for the suppression of signs of infection in 4500 of the patients, who presented as suffering from a space-occupying lesion. The most accurate diagnostic tool was angiography, which localized the lesion in 9000 and suggested its nature in 61%. Brain scan may prove as satisfactory.Staphylococcus was cultured in about two-thirds of the cases. Mortality seemed to decrease concomitantly with the advent of more potent antibiotics. The treatment of choice in terms of both mortality and morbidity seemed to be enucleation after previous sterilization. The hazards of radical surgery should be taken into consideration.

THE occasions on which foreign bodies, such as chicken or fish bones are accidentally swallowe(l with the food, must be very numerous. Usually unless they lodge in the pharynx or cesophagus, they give rise to no immediate symptoms or alarm, and doubtlessly in the great number of instances, are passed without further incident. In certain cases, however, the relative frequency of which it is obviously impossible to determine, their further progress becomes arrested at some point in the intestinal tract. Then, as a result of their physical characteristics which conduce to penetration and perforation, they may give rise to clinical manifestations which are extremely puzzling.A word of explanation is perhaps in order to account for the limitation of this communication to the consideration of only non-metallic foreign bodies. Metallic foreign bodiies are excluded because they present a different clinical problem. The ingestion of one of these objects, such as a pin, needle, etc., is a more or less dramatic and alarming event, which brings the patient under observation at once, or at least impresses itself vividly upon his memory. The problem then resolves itself into the observation and treatment of a potentially perforating foreign body, known to be present in the gastroenteric tract. Furthermore the ease with which they are demonstrated by the X-ray, gives definite knowledge of their presence, and facilitates the subsequent study of their course. With the non-mletallic type of foreign body, under discussion, however, the patient presents himself as a rule only after perforation has occurredi. And, as will be seen, with marked variations in the clinical picture. By this time, he has forgotten, if he ever noted, the swallowing of a chicken or fish bone, and he certainly never thinks of connecting the present serious plight, with so minor an occurrence. The X-ray of these cases is of practically no assistance.In the twelve cases, which are here reported, fish bones were found six times, fragments of chicken bone five times, and a sliver of wood (toothpick) once. However, any relatively short, sharp-pointed non-metallic foreign body, would fall into this category. In the literature, cases due to bristle, bits of stubble, a piece of cherry stem, etc., have been reported. Fish bones, however, are by far the most frequent.The caecum and flexures of the colon are the most frequent sites of perforation. Arrest of one of these foreign bodies in the normal small intestine, is uncommon. On the other hand, conditions such as prevail in a large hernial sac, tend to favor the lodging of a sharp-pointed! object at that point. 928

A series of 126 patients with meningioma, operated upon 7-17 years ago, is reviewed as to the recurrence of the tumour. The overall rate of recurrence of the histologically benign lesions was 29 per cent. The most important factors influencing the prognosis were the site of the tumour and the degree of radicality of excision. Both factors were illustrated best in the parasagittal meningiomas, which carry the highest rate of recurrence. Infiltration of tumour into adjacent bone does not necessarily carry a higher risk of a clinically relevant recurrence. There seems to be a great variation in the rate of growth of different meningiomas.

The aim of this paper is to prove strengthenings of three theorems appearing in Jensen [1].