Metastases to bone in medulloblastoma. A report of five cases

Medulloblastoma is a relatively common intracranial neoplasm in childhood. Its extraneural spread was, until recently, thought to be a rare occurrence. Metastases are most commonly to bone. Five patients with medulloblastoma metastatic to bone are presented, and findings are compared to those of previous reports. Two of the five cases showed patchy extensive osteosclerosis of the pelvis and/or proximal femora. One case had concurrent lymph node involvement. In patients with past or present medulloblastoma and bone pain, metastases to bone should be excluded. Medulloblastoma metastatic to bone is a rare cause of extensive osteosclerosis.

Direct spread of medulloblastoma in adjacent extrameningeal tissues

A case of a medulloblastoma with extensive intradural dissemination and direct tumour spread from a lumbosacral deposit in the pelvis is presented. A review of the literature revealed six similar cases. In all of them direct invasion of contiguous structures occurred at sites of secondary deposits. Two predilection site were identified: 1. The anterior fossa with tumour invasion of the paranasal air sinuses. 2. The lumbosacral spine with tumour extension into the retroperitoneum and pelvis. Generally, this unusual mode of tumour spread indicates a final stage in the course of the disease. The possible pathogenesis is discussed.

"Primary" leptomeningeal dissemination of medulloblastoma. Report of an unusual case

The Authors report the case of a 5-year-old boy medulloblastoma presenting with "primary" widespread diffusion in the subarachnoid spaces of the posterior fossa without true mass lesion. The diagnosis, suspected first on the basis of the computed tomography (CT) findings, was confirmed by cytological examination of the cerebrospinal fluid (CSF) and by surgery. The Authors analyse the peculiar clinical features (rapid and severe deterioration of general conditions, hyperacute course of the illness and fatal issue) and the morphological aspects of the tumor (CT and surgical findings). To our knowledge no case of "primary" dissemination of medulloblastoma was previously reported.

Adult cerebellar medulloblastomas: the pathological, radiographic, and clinical disease spectrum

The records of 34 patients over 16 years of age with cerebellar medulloblastoma were retrospectively reviewed. All patients were treated by surgery, and all surviving patients were given radiation therapy. The imaging characteristics of this rare entity were evaluated with regard to the tumor location in the cerebellum, and the prognostic effects of histological characteristics such as neuronal or glial differentiation and the presence of desmoplasia were investigated. Neither histological parameters nor tumor location (median, paramedian, or lateral cerebellar) affected patient survival. The desmoplastic variant was encountered in 38% of these adult medulloblastomas and occurred in all three cerebellar locations. The degree of surgical resection did not have a major effect on long-term survival; long-term survival was possible even in patients who had received only a biopsy. The extent of initial radiation therapy was positively correlated with recurrence-free survival; full neuraxis irradiation was associated with a 13% incidence of delayed spinal metastases, whereas 75% of patients treated with irradiation of only the posterior fossa and/or the whole brain developed spinal deposits. A similar local recurrence rate (12.5%) was noted in both irradiation groups. Chemotherapy resulted in palliation in some patients with metastatic disease.

Computed tomography in intracranial, supratentorial metastases in children

This study compares the CT characteristics in a consecutive sample of supratentorial metastases (n = 31) with primary tumors of the same location (n = 49) in childhood. Postcontrast CT was performed in all but one of the metastases cases. In all but one of these children the location and type of primary tumor was known at time of occurrence of cerebral metastasis. Primary CNS tumors (n = 12) had a higher incidense of supratentorial metastatic spread than tumor originating elsewhere. Three children had diffuse subarachnoid seeding, while 28 had solid tumors (21 solitary, 7 multiple). The predilection location for the solid metastases was the gray-white matter junction (n = 12). The following CT findings were significantly less frequent in metastases than in primary tumors (P less than 0.05): Midline location, calcification and cyst formation. On the other hand bleeding, pronounced contrast enhancement and location in the gray-white matter junction were more frequent in the metastatic group (P less than 0.05).

Primary spinal medulloblastomas?

Two cases with spinal medulloblastoma are presented in which even modern neuroradiological methods (computed tomography - CT - and nuclear magnetic resonance imaging - NMR -) did not demonstrate intracranial lesions. These cases should be considered to be primary spinal medulloblastomas, even if until now the existence of real primary spinal medulloblastomas has been doubted.

Computerized tomography findings in pediatric patients with posterior fossa lesions

The posterior fossa (PF) is a common site of lesions in the brain during childhood and infancy. Sixty pediatric patients with PF lesions shown on CT scans are presented. The most common lesions (48.4%) were intra-axial tumors, such as astrocytomas, medulloblastomas, and ependymomas. The tumors were relatively large at the time of diagnosis. The largest were medulloblastomas (mean maximal diameter 45.6 +/- 9.7 mm). Other abnormal findings of the PF were congenital anomalies, vascular lesions, hypoplasia and atrophy. A common approach to PF lesions is offered, emphasizing the variability, the incidence, and the different CT features of the lesions.

Medulloblastoma in infancy associated with omphalocele, malrotation of the intestine, and extrophy of the bladder

A successfully treated case of infantile medulloblastoma is presented that was associated with omphalocele, malrotation of the intestine, and extrophy of the bladder. A 5-month-old boy was admitted due to disturbance of consciousness and was diagnosed by computed tomography as having a medulloblastoma. Ventricular drainage, subduralperitoneal shunt, and removal of the tumor were performed, and postoperatively radiation therapy was administrated with 4,000 rad to the whole brain. He was discharged in good condition and no evidence of recurrence was observed at the 14th post-operative month. Medulloblastomas associated with congenital anomaly of the abdomen have been only rarely reported. The authors postulate that between the second and third month of gestation an intrinsic or extrinsic factor may have caused the development of the medulloblastoma, as well as anomalies of the abdomen such as omphalocele, malrotation of the intestine, and extrophy of the bladder.

Medulloblastoma in association with the Coffin-Siris syndrome

An 8-year old patient with Coffin-Siris syndrome is presented, who was found to have a medulloblastoma during the evaluation of apnea and ventilator dependency. Although several cases of Dandy Walker cysts and one case of brain-stem heterotopia have been described in this rare syndrome, this is the first report of medulloblastoma in a patient with Coffin-Siris syndrome. Possible pathogenetic mechanisms are briefly discussed.

The incidence and distribution of spinal metastases in children with posterior fossa medulloblastomas

Myelography was performed postoperatively in 34 children with posterior fossa medulloblastomas. In 15 patients, there was myelographic evidence of intraspinal spread. This was more common in younger patients. The spread varied from a single nodule to extensive disease with spinal block. The lumbosacral canal was affected most often. Three patients with positive myelograms had negative cerebrospinal fluid cytology. Only one patient had symptoms referrable to the spine.

Gastroparesis secondary to a medulloblastoma of the posterior fossa

A patient with a 4-month history of unexplained nausea and vomiting is reported. The only abnormality found initially was severe gastroparesis found by gastric emptying scan. Subsequently, a posterior fossa tumor was found. The pathogenesis of this unusual presentation and the role of the gastric emptying scan is discussed.

Computed tomography in management of medulloblastomas

The neuroradiological studies of 116 patients with histologically verified medulloblastomas, which had been examined with plain and contrast-enhanced computed tomography (CT), were reviewed. The typical CT appearances of a well-defined, hyperdense enhancing mass in the vermis, with surrounding oedema, occurred in 60% of this series. Atypical features include calcification (17%), cystic or necrotic regions (47%) or poorly defined margins and lack of enhancement (7%). Such features in a vermis mass presenting in the first decade, especially in a boy, should not be considered against the diagnosis of medulloblastoma, but may be misleading when the tumour predominantly involves a cerebellar hemisphere.

Correlation of tumor plasminogen activator with peritumoral cerebral edema. A CT and biochemical study

Extracts from 15 human cerebral tumors were tested by a fibrin-plate plasminogen-dependent assay for levels of tumor plasminogen activator (TPA) activity. The TPA activity was correlated with the amount of perineoplastic edema as quantified on computerized tomography (CT) brain scanning. Analysis of the results showed a correlation coefficient of 0.72 when all tumors were included. Analysis of the nine tumors with the highest TPA levels showed a correlation coefficient of 0.96. One metastatic tumor had the highest level of TPA activity, equivalent to a pure 100-micrograms/ml solution of urokinase, and the greatest amount of cerebral edema on CT. Meningiomas generally had the next highest levels of TPA activity and edema, followed by astrocytomas of varying grades, which generally had the lowest level of TPA activity. However, three astrocytomas that had low TPA activity also had significant edema surrounding the tumor, indicating that more than one mechanism may be producing peritumoral edema. There was no correlation between tumor size and the amount of perineoplastic edema. These preliminary results suggest that TPA's may be involved in the production of perineoplastic cerebral edema and that treatment of patients with currently available plasminogen activator inhibitors may be successful in reducing peritumoral edema.

Medulloblastomas: a review of 11 cases

The authors review 11 cases of medulloblastomas, 9 of which were diagnosed and treated in the last 6 years. All were uniformly treated by surgery, radiotherapy and chemotherapy, according to the SIOP protocol. Complications and results are described.

Subarachnoid hemorrhage from brain tumors in childhood

Six children are reported in whom subarachnoid hemorrhage was an initial symptom of brain tumor. In our neurosurgical clinics, this represented 3.6% of pediatric brain tumors and showed a frequency equal to aneurysmal rupture among nontraumatic subarachnoid hemorrhage of children. In pediatric patients, hemorrhages from brain tumors occur predominantly in the posterior fossa. The medulloblastoma, which had been believed to bleed rarely, is now realized to be a common source of tumor hemorrhages in such cases. The introduction of CT scan facilitates early recognition of hemorrhagic stroke from brain tumors and prompt management for acute intracranial hypertension and brainstem dysfunction. Although the patients achieve favorable recovery from their initial catastrophic condition, the ultimate prognosis, in the majority of cases, is still rather poor because such hemorrhages usually develop from a malignant tumor. The present and other recent reports indicate that the incidence of hemorrhagic stroke from brain tumors in pediatric patients is much higher than has been thought and is an important cause of subarachnoid hemorrhage in this age group.

Central neurogenic hyperventilation in a patient with medulloblastoma

Central neurogenic hyperventilation is a rare but important cause of the frequently observed phenomenon of hyperventilation. Its diagnosis demands that primary respiratory or metabolic causes, as well as cerebrospinal fluid abnormalities, be ruled out. We hereby describe a patient whose attacks of hyperventilation were the presenting sign of her disease and might be consistent with the central neurogenic mechanism. This patient suffered from a medulloblastoma which compressed the pons. After removal of the tumor the hyperventilation attacks ceased.

Preferential accumulation of 11C in human brain tumors after intravenous injection of 11C-1-pyruvate

Regional cerebral turnover of 11C following intravenous injection of 11C-1-pyruvate was investigated in 12 patients with brain tumors. The positron emission tomography (PET) image taken at 10-15 min after the injection always demonstrated a high concentration of 11C in tumor, and thus visualized precise tumor contours. This phenomenon was not influenced qualitatively by the variation of blood flow in the tumor. Brain edema associated with the tumor was not visualized. We conclude that the localization of brain tumors would be well determined by the PET scan, using 11C-1-pyruvate.

Spinal intramedullary spread of medulloblastoma. Case report

The case of an 11-year-old boy is reported in whom two intramedullary lesions developed at the thoracic-cervical and thoracic-lumbar junctions 2 1/2 years after resection and irradiation of a medulloblastoma in the posterior fossa. There was no evidence of subarachnoid spread of the tumor. Magnetic resonance imaging was used to localize these lesions, and provided much better diagnostic information than either computerized tomography scans or myelograms.

[Clinico-pathological studies of CSF dissemination of glioblastoma and medulloblastoma]

Clinico-pathological findings of CSF dissemination which was diagnosed on CT scan, were studied on 13 cases of glioblastoma and 9 cases of medulloblastoma. The type of CSF dissemination and the prognosis of patients were both different between glioblastoma and medulloblastoma. In the former, the dissemination was predominantly in ventricular walls and in the latter, in basal cisterns. The mean survival time after the diagnosis of dissemination is 6 months of glioblastoma as compared with 13 months of medulloblastoma. The Pathological studies show that subependymal and/or subpial infiltration of tumor cells, and thickness of arachnoid membrane by marked mesodermal reaction were demonstrated in cases of glioblastoma. On the contrary, tumor cells of medulloblastoma grow markedly in the subarachnoid space and/or on the ependymal layers. From these pathological findings of CSF dissemination, it will be resulted that the prognosis of glioblastoma is much more poor that of medulloblastoma.

Intracranial neoplasms during the first year of life

During a 7-year period, from January 1976 to December 1982, 470 brain tumors were treated at the Hospital de Niños Ricardo Gutierrez in Buenos Aires, 40 of which occurred in infants under 1 years of age. Diagnosis was at best tentative because most cases were referred on account of symptoms and nonspecific signs, e.g., macrocephaly, vomiting, and altered behavior. The supratentorial location was predominant over the infratentorial, with a ratio of 4:1. Craniotomies with resection of tumor were performed on all but four infants. Optic chiasm pilocytic astrocytoma, superficial brain astrocytoma, and choroid plexus papilloma were the most common histologic types. Thirty-three infants (80%) were found to have hydrocephalus complicating the brain tumor, but only 15 of them were shunted, because 4 infants died, and in 14, hydrocephalus remitted after the operation. After 2-9 years of postoperative observation, 16 infants (40%) live tumor-free and have normal neurological examinations, 5 (12%) suffer moderate deficits, and 19 (48%) have died.

Cystic adult medulloblastomas

The computed tomography scans of four patients who had a medulloblastoma are reviewed. In all the cases, atypical findings were present--specifically, cystic or lucent areas within the tumor. The importance of this uncommon finding associated with adult medulloblastoma is discussed.

Medulloblastoma in childhood: results of radical resection and low-dose neuraxis radiation therapy

This review concerns 22 children who were treated from 1980 through 1983 for medulloblastoma in the posterior fossa. Treatment included attempts at radical resection of the tumor and postoperative craniospinal radiation therapy, with 5000 to 5500 rads directed to the posterior fossa and 2500 rads to the remaining craniospinal axis. This lower radiation dose to the neuraxis was used to avoid late adverse effects upon the growing central nervous system of the children. Gross confirmation of total resection was obtained in 13 patients (the "total resection group"); however, nine patients had a subtotal resection leaving a small portion of the tumor extending into the cerebellar peduncles or the cerebellopontine angle, or else encasing the posterior inferior cerebellar artery (the "subtotal resection group"). Six patients in the total resection group demonstrated tumor extension into the cerebellar peduncles, which was removed by means of a surgical carbon dioxide laser without neurological sequelae. Biopsy of the arachnoid membrane from the cisterna magna and cytological examination of the cerebrospinal fluid (CSF) prior to manipulation of the tumor were carried out in 12 patients. All but one showed dissemination of medulloblastoma cells. Myelography and CSF cytological study were undertaken 2 months after radiation therapy in 12 patients and were positive in two. There were no case mortalities in the total resection group during the 24- to 67-month follow-up period, whereas the 1-year survival rate in the "subtotal resection group" was only 44.4%. This study suggests that medulloblastoma can be controlled with a low radiation dose to the neuraxis, should a grossly confirmed total resection be achieved at craniotomy.

CT-compatible system for stereotactic biopsy and brachytherapy of infratentorial tumors

Teletherapy of nonresectable radiosensitive brain tumors is the mainstay of adjunctive treatment. In the past two decades brachytherapy has begun to play an ever-increasing role, particularly on the European continent. Yet this attention has been addressed almost exclusively to lesions of the supratentorial space. This article describes modifications of the Riechert-Mundinger stereotactic system which were made by one of us (P.D.) to allow an unencumbered yet precisely computerized stereotactic approach to posterior fossa lesions for biopsy and interstitial radiation with iridium 192. A case report is described to illustrate the technical details involved in such an undertaking.

Pediatric brain computed tomography

Computed tomography today provides good anatomic depiction of the brain and its gross disease processes that have as a manifestation alteration of brain density, disturbance in blood-brain barrier, or mass effect. As such, computed tomography often provides valuable diagnostic information in the appropriate clinical setting. This article reviews many of the more common pediatric central nervous system disease states that have been demonstrated more easily as a result of computed tomography.

Medulloblastomas: a review of modern management with a report on 75 cases

The authors summarize the 8-year experience of a tertiary medical center with 75 cases of medulloblastoma in Saudi Arabia. A discussion of the evolution of modern management of this difficult problem ensues. As 5-year survival statistics approach 80% in some institutions, attention is being focused on the long-term effects of modern therapy and the quality of life led by these children.

Primary CNS tumors presenting as cerebellopontine angle tumors

Adult patients with posterior fossa tumors arising from the cerebellum and brainstem are reported. In each case the tumor presented as a cerebellopontine angle tumor and not as an intra-axial tumor. Tumors of CNS origin are uncommon in the posterior fossa in adults, but they may be seen by the otologist if the presenting symptoms are audiologic or vestibular. Computed tomography scanning will not always distinguish these lesions from the much more common extraaxial neurinoma, meningioma, or cholesteatoma. The progression of symptoms is more rapid in these patients, and other associated neurologic deficits are more common. The auditory brainstem response may demonstrate characteristic abnormalities in these patients. The differential diagnosis of these tumors in adults is discussed and the recent literature reviewed.

Rational approaches to the chemotherapy of medulloblastoma

Medulloblastoma is the most common primary tumor of the CNS in childhood. Surgical intervention alone will not cure this tumor, and the addition of whole neuraxis irradiation has led to a 50 to 60 per cent, 5-year survival. The role of adjuvant chemotherapy is unclear, although certain subgroups of high-risk patients may benefit from this modality. Agents that have demonstrated activity against recurrent disease include vincristine, cyclophosphamide, cisplatin, methotrexate, dibromodulcitol, and the combination of procarbazine-vincristine-CCNU. However, responses are generally transient and virtually no cures are reported. New, rationally selected agents are clearly needed. In vitro and in vivo models of human medulloblastoma using the medulloblastoma-derived cell lines TE-671 and D283 Med may allow such an approach. Phase II trials using the drugs effective in these models may identify active agents that will ultimately increase survival when used in an adjuvant setting.

Computed tomography in the diagnosis of intracranial neoplasms in children

The authors discuss their original observations using computed tomography (CT) in the diagnosis of posterior fossa neoplasms in children. The subject of CT diagnosis of childhood supratentorial tumors is also reviewed. However, despite the documented value of CT, the authors believe that magnetic resonance imaging (MRI) will eventually offer certain advantages that will make MRI the primary imaging modality for intracranial neoplasms in children.

Myelography for staging medulloblastoma

Thirty-eight patients with newly diagnosed medulloblastoma were studied with myelography and cerebrospinal fluid (CSF) cytology studies before radiotherapy. Seventeen (45%) patients had evidence of dissemination beyond the posterior fossa. Spinal cord lesions were demonstrated in ten patients (26%). Negative results of CSF cytology studies did not preclude demonstration of cord involvement. Children younger than 5 years were more likely than older patients to have spinal cord involvement at diagnosis. Patients who were truly M-0 did better in terms of absolute survival but not relapse-free survival when compared with patients with dissemination. Myelography and cytology studies are necessary in the evaluation of all newly diagnosed patients with medulloblastoma and may also be indicated for patients with other brain tumors with a known propensity for dissemination.

Medulloblastoma in infants and children: computed tomographic follow-up after treatment

Thirty-six proven cases of medulloblastoma were reviewed by serial CT follow-up examinations from 4 months to 10 years, 2 months after the initial diagnosis, with a mean follow-up time of 3 years, 9 months. The children ranged in age from 10 months to 16 years, 7 months at the time of follow-up. The tumor recurred at the primary site in 20 cases (56%). Leptomeningeal metastasis was demonstrated on CT in 14 cases (39%); seven of these patients also presented with solid subarachnoid metastases. Thirteen patients (36%) showed evidence of severe brain atrophy, which was confined to the posterior fossa in seven of the 13. Calcification resulting from mineralizing microangiopathy developed in five cases (14%), including three patients who had extensive dystrophic calcification in the corticomedullary junction and the deep-seated nuclei of the cerebrum and cerebellum. Only one case of leukoencephalopathy was observed. The patterns of tumor recurrence in the posterior fossa that is severely deformed by surgery and other treatment modalities and leptomeningeal spread of tumor are discussed.

Surgery of cerebellar astrocytomas, ependymomas and medulloblastomas in children

A report is given on 118 children operated on for cerebellar astrocytoma, ependymoma or medulloblastoma in 1968-1982. During the first period (1968-1975) when the diagnosis was based on ventriculography and the operation performed later on the same day, the surgical mortality was 5%, 22%, and 16% respectively in these tumours. In the period since 1976, during which the diagnosis was based on CT and preoperative shunting was routine with the posterior fossa operation performed a week later and an operation microscope was available, no surgical mortality occurred. In patients with ependymoma or medulloblastoma the shunt was left in permanently; in patients with astrocytoma the shunt was removed if the patient tolerated its closure. The prognosis for astrocytoma was excellent. The 10-year survival rate was 97%. The five-year survival rate for medulloblastoma was 27% and the 10-year survival rate 13% which are less than the rates generally reported. For ependymoma patients the prognosis was poor whatever the therapy.

Treatment of medulloblastoma using a computer-controlled tracking cobalt unit

Radiation therapy of the length of the spinal column presents various clinical and physical problems. The completed plan may be complicated to set up, be time-consuming and require daily variation to achieve reasonable dose homogeneity. A case of medulloblastoma is used to illustrate the steps in producing a plan for dynamic treatment using a computer-controlled tracking cobalt unit. After definition by computed tomography, the target is considered in segments in order to develop a plan which keeps the spinal cord constantly positioned at the beam isocentre. The main computer is used to develop the patient treatment file and information is transferred to a second computer which controls and monitors the safe functioning of the cobalt unit. The cranial fields are treated separately in a conventional way. Good and consistent control of the dose distribution is achieved along the entire target volume. This technique is a marked improvement over all existing methods of treating the spinal axis.

Early CT detection of intracranial seeding from medulloblastoma

Since 1975, intracranial subarachnoid metastases of medulloblastoma have been detected in seven of 23 initial contrast-enhanced computed tomographic (CT) scans in children with proven medulloblastoma. Furthermore, four of the seven cases with subarachnoid seeding were diagnosed after the introduction of high-resolution contrast-enhanced CT. Only three cases of seeding had been detected in the previous 17 low-resolution cases studied with CT. Thus, it is quite likely that the incidence of subarachnoid metastases may be substantially more than the overall figure of 30% indicated by this series. This may have an impact on the treatment of these patients, since the frequent appearance of metastases may indicate the need for more vigorous chemotherapeutic regimens. One should be aware of the possibility of early intracranial subarachnoid seeding and that it can be demonstrated by contrast-enhanced CT. This is particularly true when using high-resolution scanners in conjunction with 5 mm sections through the posterior fossa.

Intraspinal seeding from intracranial tumors in children

Cerebrospinal fluid-borne metastases were demonstrated by metrizamide myelography in 20 children with primary intracranial tumors, posterior fossa medulloblastomas being the most common. The lumbosacral region was affected most often, with nerve root thickening, nodularity, and irregularity of the thecal sac. Cord cloaking, nodularity, and meningeal disease were common in the cervical and thoracic areas. Intraspinal spread from primary intracranial tumors signals a poor prognosis. However, the early detection of intraspinal spread afforded by metrizamide myelography can alter therapy and thereby improve prognosis.

Intracranial neoplasms

CT has made possible the diagnosis of intracranial neoplasms with greater precision than other currently available neurodiagnostic studies. Because it is not always possible to determine the precise pathologic features of these neoplasms without angiography and surgical biopsy, over-reliance on CT should be avoided.

Intraventricular mass lesions

Determining the precise etiology of an intraventricular mass can be a difficult diagnostic problem. CT and angiographic findings were reviewed in a series of 73 patients who had intraventricular masses. The histologic diagnosis can be suggested preoperatively by an analysis of the frequency of lesions occurring at a given ventricular location, lesion density before and after administration of contrast material, age and sex of the patient, morphologic appearance of the mass, and presence or absence of hydrocephalus. Angiography is useful when meningioma, choroid plexus papilloma and carcinoma, or arteriovenous malformation are considered. The differential features of each diagnostic entity are discussed.

Cerebrospinal fluid entrapment cysts with subarachnoid dissemination of medulloblastoma: CT findings

We report an unusual case of meningeal dissemination of medulloblastoma in which multiple cerebrospinal fluid entrapment cysts developed within the cerebral fissures and cisterns. The condition was first diagnosed by CT. Cysts reduced in size following radiotherapy.

Parameters of infiltration in posterior fossa tumours of childhood using a high resolution CT scanner

The computed tomographic changes in 23 posterior fossa tumours of childhood scanned on a GE 8800 scanner have been compared with the detailed operative reports in order to evaluate morphological features indicative of infiltration. The study indicated that the cyst wall of a cystic astrocytoma was always easily enucleated and was free from infiltration and that a sharp enhancing edge of a medulloblastoma or centrally necrotic astrocytoma was usually also not the site of infiltration. Other features however were found to be unreliable.

The impact of myelography on the treatment results for medulloblastoma

Two series of newly diagnosed patients with medulloblastoma are compared in terms of survival, relapse-free survival, and sites of relapse. Patients in series I were all diagnosed and treated prior to 1974 and did not have the benefit of myelography and CSF cytology for staging. All patients treated after 1974 had myelography and most had CSF cytology studies prior to radiotherapy. In addition, patients in the latter series were all followed with CT scanning. Improved survival and relapse-free survival rates were seen in the series II patients. Approximately 30% of the staged patients have had abnormal myelograms. It is suggested that involved portions of the cord be treated with higher doses than the usual prophylactic doses. The better results seen in the series II patients are probably due in part to a combination of adequate staging with radiation doses to the neuraxis based on the staging, close followup with CT scanning, and aggressive re-treatment of relapses.

[Brain tumors in children. Neuroradiologic studies]

194 patients bearing intracranial tumors were reported. Incidence in relation to the age and diagnostic techniques was evaluated and criticized. A serie of a picture concerning CT, Angiography, Pneumoencephalography and Ventriculography with contrast medium are presented.

[Neuroradiology in cerebral gliomas]

CT Scan has greatly helped preoperative diagnosis in brain tumors. CT Scan alterations are found in about 95% of brain tumors and the most modern instruments can pick-up even small alterations, locate them precisely and, in 80% to 90% of the cases can give their exact extension. But precise CT-scan diagnosis in brain tumors can be done in only 80% of the cases when in a supratentorial site; about 90% in infratentorial localizations. Differential diagnosis difficulties occur with metastasis, abscesses, infarction, meningiomas, and vessel malformations. Angiography does not always solve these diagnostic problems left uncovered by CT Scan and not infrequently surgical proof is necessary.