DIAGNOSTIC VALUE OF BRAIN SCANNING IN CHILDREN

Ninety five brain scans were carried out on 70 infants and children. Technetium 99m pertechnetate was used exclusively, because of its energy level and short physical half-life. Brain scanning provides valuable information regarding the presence of many kinds of neoplastic as well as non-neoplastic lesions. Positive scan results related to the nature of the lesions are; infections 67%, vascular lesions 66%, tumors 753, trauma 67%, subdural hematoma 88%, congenital diseases 59%, degenerative diseases 0% and convulsive disorders 33%. Scan findings were compared with the findings of plain X-rays of skull, cerebral angiography, pneumoencephalography and electroencephalography. The accuracy of scanning does not necessarily exceed that of other methods of investigation, but it provides a valuable information and increases the accuracy of diagnosis in most cases in children. The possible mechanism of positive scanning in subdural hematoma was studied. The interval between the injection and the timing of scanning was found to be an important factor in diagnosis. Brain scanning should have a place of primary importance for the work-up of children in neurosurgical practice

BRAIN SCANNING OF SUBDURAL HEMATOMA IN INFANTS AND CHILDREN

We performed 99mTc pertechnetate brain scanning 27 Limes on 15 infantile subdural hematoma cases. These scannings gave positive results in 74%, doubtfully positive in 18%, and negative in 8%. In selected cases, scans were obtained after appropriate delay periods as well as at conventional times. In some cases, scans which were initially interpreted as borderline or negative were read as definitely abnormal on delayed studies. The radioactivity in the serial blood and subdural samples was measured in a well-type scintillation counter. This study clarified a part of the biodynamic mechanism underlying the successful detection of infantile subdural hematomas by external scintillation scanning. Our result shows that both the subdural fluid and subdural neomembrane influence the production of a positive scan, but whether the isotope is localized predominantly in the membrane or in the subdural fluid depends upon the kind of radioisotope used, hematoma age, the nature of the subdural fluid and the time interval between the injection of radioisotope and scanning. The total volume of the subdural space is assessable more exactly by the isotope dilution method than by the simple 2 dimensional gamma ray image of the subdural hematoma. This tells more of the clinical value because of its importance in planning the therapy

DYNAMIC STUDY ON CEREBROSPINAL FLUID CIRCULATION AFTER SUBARACHNOID HEMORRHAGE

Alterations in the cerebrospinal fluid (CSF) circulation after subarachnoid hemorrhage (SAH) were examined in 19 patients. Sources of hemorrhage were aneurysm in 17 cases, arteriovenous aneurysm in one and unknown in one. Cistenography was performed using 1 mCi of 169Yb diethyltriaminepentaacetic acid which was given intrathecally by lumbar injection. Persistent ventricular filling was seen in 48% of the cases and transient ventricular filling in 33%. The radioactivity in serial blood samples was measured by a well-type scintillation counter. The relationship of cisternogram to classification of patient s condition by Hunt was found to be closely related to the degree of abnormality of CSF circulation. The patient s history of rebleeding was also found to influence the degree of abnormality in CSF circulation. In regard to the site of aneurysms, those in the circle of Willis appeared to cause norm al pressure hydrocephalus more frequently. Shunt operation was performed on 6 cases, 4 of whom showed improvement. Indications for shun t were determined according to clinical syndrome and diagnostic tests such as angiography, pneumoencephalography and cisternography. In addition to these, test for radioactivity in the peripheral blood was found useful for evaluation of the condition in CSF circulation

RADIOISOTOPE SCANNING FOR THE SPINAL CORD TUMOR

Radioisotope scanning with 99mTc-pertechnetate or 67Ga-citrate for the spinal cord tumors was reported. Six patients with spinal cord tumors including 2 ependymomas, 1 neurinoma, 1 metastatic medulloblastoma, 1 metastatic astrocytoma, and 1 metastatic pinealoma as well as 6 patients with non-neoplastic lesions were examined with this method. Two out of 6 cases with tumors showed positive scans and two equivocal scans. This new method is different from myeloscintigraphy and radioisotope angiography as already reported. It directly demonstrates tumor itself like brain scanning and is very useful as nontraumatic method for screening spinal cord lesions, especially in poor risk patient. The usefulness and limitation of this method are discussed