Elizabeth Hoppe-Hirsch

Intellectual outcome in children with malignant tumors of the posterior fossa: influence of the field of irradiation and quality of surgery

The purpose of this study was to determine the respective parts played by cerebral hemisphere irradiation, posterior fossa irradiation, and surgery in the poor late functional results often observed in children treated for medulloblastoma. To do this we compared the intellectual outcome in a series of 59 children operated on for medulloblastoma, who had received whole-brain irradiation, to that observed in a series of 37 children operated on for ependymoma of the posterior fossa, who had received radiotherapy only on the posterior fossa. Only patients who had survived for more than 2 years without recurrence were included. At the assessment 1 year after treatment, intellectual outcome was somewhat better in the ependymoma group, but the difference was not statistically significant. At the long-term follow-ups at 5 and 10 years the results remained stable in the children treated for ependymoma, around 60% having an IQ above 90, whereas the intellectual level of the children treated for medulloblastoma was seen to have deteriorated progressively: 20% had an IQ above 90 5 years after treatment and only 10% at the 10-year followup. This progressive degradation is most likely due to the irradiation of the cerebral hemispheres, as this prophylactic irradiation constituted the only difference between the two groups. Moreover, irradiation to the posterior fossa did not seem to affect intellectual functions, since in the group of children with ependymomas the proportion of IQs above 90 was high and remained stable over the years. Surgery was certainly responsible for some poor results. The percentage of IQs above 90 observed 1–2 years after treatment was between 70 and 80 when no postoperative complications occurred, and only between 20–40% in the presence of postoperative complications. Postoperative aggravation was in most cases related to a brain-stem lesion. These results encourage the reduction, when possible, of irradiation to the cerebral hemispheres and underline the importance of the quality of surgery.

Medulloblastoma in childhood: progressive intellectual deterioration.

A series of 120 medulloblastomas in children operated on between 1967 and 1987 at the Hôpital des Enfants-Malades has been reviewed in order to check whether the conclusions of our study published 10 years ago have remained valid and, in particular, to verify whether the quality of life of these patients, which had been found to be poor at the time, had improved or worsened over the years. The postoperative mortality for the whole series was 6.5% there have been no deaths in the 35 patients operated on after 1980. The overall survival rate for the 120 children was 60% at 5 years and 53% at 10 years; for the patients who completed radiotherapy, the survival rates was 73% at 5 years and 64% at 10 years. Survival rates were surprisingly better in patients treated when under 6 years of age than in older children. They were also better in girls than in boys, and in desmoplastic compared with other medulloblastomas; however, the differences were not significant. When comparing the groups after total or subtotal resection of tumors, survival rates were not significantly different, but were lower in the small group of partial resections. Cell differentiation did not influence the prognosis. Psychological sequelae were significant and worsened over the years. Five years after treatment 58% of the children showed an IQ above 80; 5 years later this group included only 15% of the patients. These psychological sequelae were related to age at the time of radiotherapy: the younger the child, the lower the final IQ. Five years after treatment, 40% of the children had a normal academic level; 5 years later this group was reduced to 11%. Ten years after treatment, 36% of the patients were unempolyed and 64% worked in a protected environment. No patient had normal employment. These disastrous results concerning the quality of life of these medulloblastoma patients justify new trials with reduced doses of irradiation over the hemispheres, at least in low-risk groups.

Late outcome of the surgical treatment of hydrocephalus

Abstract The purpose of this report is to analyze the long-term outcome in hydrocephalic children treated by shunt placement and in particular their psycho-intellectual development. In the case of shunt placement postoperative mortality is virtually nil, and the overall mortality rate after 10 years of follow-up has been reduced to less than 5%. Morbidity, in contrast, is far from satisfactory. This study was conducted in 129 consecutive children with nontumorous hydrocephalus who underwent a first shunt insertion before the age of 2 years between 1979 and 1982 and who were followed up for at least 10 years. The final neurological examination revealed a motor deficit in 60%, visual or auditory deficits in 25%, and epilepsy in 30%. The final IQs were above 90 in 32% of the children, between 70 and 90 in 28%, between 50 and 70 in 19%, and lower than 50 in 21%. Integration into the normal school system was possible for 60% of the children, but half of them were 1–2 years behind their age group or having difficulties; 31% were attending special classes or were in institutions; and 9% were considered ineducable. The presence of behavioral disorders was a determinant factor for scholastic and social integration. Such disorders were frequent, and were characterized as severe in 30%. A relationship between final outcome and etiology, initial ventricular size, and epilepsy was observed. These results are used as the basis of a discussion on how morbidity might be improved.

Pericerebral Collections after Shunting

Nineteen pericerebral collections (18 subdural and 1 epidural) occurred in a series of 682 consecutive initial shunt insertions for hydrocephalus in children, performed between 1976 and 1984. No collections were observed in 358 reoperations performed in the same patients during the same period. The incidence rate of this complication is nearly four times higher after 2 years of age than in younger children (6.5% versus 1.7%). The rate is also higher, regardless of age, in noncommunicating than in communicating hydrocephalus. Pericerebral collections are observed with high- as well as low-closing pressure valves. Pericerebral collections after shunting were diagnosed in 80% of the cases less than 2 months after surgery. They were asymptomatic in nearly 60% of the cases but could become symptomatic later when they were not treated. At the onset at least, these pericerebral collections are compensated by the outflow of an equal quantity of intraventricular CSF so that ICP is only moderately elevated. Postshunt pericerebral collections may be the consequence of CSF loss at the time of surgery. In most cases, however, they are due to a CSF overdrainage by the valve. This overdrainage, together with the reversal of CSF flow in the highly resistant CSF pathways of hydrocephalus, establishes a pressure lower in the ventricles than in the subarachnoid space and tends to open up the subdural space. The treatment of postshunt subdural collections is the insertion of a simple tubing without valve between the subdural space and the peritoneum, the ventriculoperitoneal shunt being left in place. With this treatment, more than 80% of the collections disappeared or were improved. No complications or secondary aggravation were observed in any of these patients.

Shunts and Shunt Problems in Childhood

Extra cranial shunting procedures (Cone et al. 1949, Matson 1951) were used to treat hydrocephalus before the work of Nulsen and Spitz (1952) and before the introduction of the Holter valve in 1956. However in most cases they were inefficient or even dangerous; they overdrained because they could not close and rapidly blocked due to tissue reaction to the constituent material.

Neurosurgery with craniotomy and CT stereotactic guidance in the treatment of intracerebral space-occupying lesions.

When intracerebral space-occupying lesions are small or located deeply within the brain parenchyma, it is sometimes difficult to localize them at surgery or to design the most direct and least hazardous surgical approach. Therefore, we have developed a method that combines conventional neurosurgical techniques with craniotomy using stereotactic guidance. We have used the Brown-Roberts-Wells (BRW) stereotactic system, which allows for computed tomography (CT) or magnetic resonance imaging (MRI) guidance and does not interfere with the absolute sterility mandatory each time a flap is created. Eleven patients were operated on using this method. The deep tumors were approached through a linear incision of the cerebral cortex. Then a needle, fixed in the right position on the arc system of the BRW, was inserted toward the surface of the lesion; the exposure was finally widened by inflation of a rubber balloon set on the stereotactic needle. This technique allows the two lips of the cortical incision to be glued at the end of the operation. Gluing with a fibrin glue avoids the postoperative subdural collections that often develop when the ventricle has been opened. Except for one case, the post-operative course was uncomplicated in these patients. No permanent postoperative neurological worsening was observed even after the removal of an intrathalamic tumor.

Malignant hemispheric tumors in childhood

Sixty-four malignant hemispheric tumors in children less than 15 years old were treated in the pediatric neurosurgical department of the H ôpital des Enfants Malades between 1970 and 1989. (1) These tumors evolved rapidly in most cases. However the pre-operative evolution in 20% of the patients had a duration of more than 6 months, which favors the hypothesis that at least one-fifth of these tumors result from malignant transformation of a benign lesion. This observation should prompt neurosurgeons to operate on all benign hemispheric tumors as soon as they are diagnosed. (2) Five of the 64 patients had two successive malignant diseases. In four cases the other malignant disease was an acute lymphoblastic leukemia. (3) Among the malignant hemispheric tumors, the grade III and IV astrocytomas had a dismal prognosis. As it is known from previous studies that grade I and II astrocytomas have a good prognosis in children, it can be concluded that grading these tumors is essential. By contrast, almost one out of two patients with malignant ependymoma was alive 5 years after treatment. This implies that the grading of ependymomas is of modest prognostic values. (4) The harmful effect of radiotherapy was evaluated by comparing the functional outcome of children operated for a benign hemispheric tumor to that of children operated and irradiated for a malignant hemispheric tumor.