Massimo Caldarelli

Shunt complications in the first postoperative year in children with meningomyelocele.

The authors analyze the incidence of early mechanical and infective CSF shunt complications and various factors that might be correlated with the incidence in a series of 170 children affected by hydrocephalus and meningomyelocele (MM), with the aim of finding specific risk factors related to this particular type of hydrocephalus. Factors investigated for correlation with CSF shunt malfunction are the following: level of the spinal malformation, age of the patient at MM repair, age at diagnosis of hydrocephalus, degree of the ventricular dilatation, age at CSF shunt implantation, modality of the surgical procedure, characteristics of CSF at operation. In the first postoperative year following CSF shunting, 45.9% of the patients presented one shunt malfunction, three-quarters of which were due to mechanical causes, and one quarter to infection. Age of the patient at diagnosis of hydrocephalus and at CSF shunt operation did not significantly influence shunt patency, nor did the surgical modality (programmed vs emergency procedure). On the other hand, MM level did influence the outcome of CSF shunting: a higher percentage of malfunctions (and in particular of infective complications) was observed among the patients with “high level” MMs than in the group with more caudal location of the spinal defect. Similarly, the degree of ventricular dilatation correlated with the incidence of complications (more severe ventricular dilatation was associated with the highest incidence of complications). The order in which MM repair and CSF shunting were carried out and the age of the patients at MM repair did not affect the occurrence of mechanical complications, whereas they had a significant effect on the incidence of infective complications. In fact, the rate of overall complications, and of infective complications in particular, was proportional the age at MM repair. Furthermore, the group of children who underwent to MM repair and CSF shunting simultaneously scored the lowest percentage of complications, although these were mainly infections; the highest incidence of complications (and in particular of infective ones) was observed in the children who underwent CSF shunting first. The most striking correlation, however, was found with the characteristics of CSF. While normal CSF values correlated with an overall incidence of complications of 39.2%, abnormal CSF values were correlated with a rate of complications of 90.9%; in particular, the rates of infective complications were 2.7% and 77.3%, respectively. On the grounds of these observations a protocol is proposed of temporary CSF external drainage in children requiring prompt relief of increased intracranial pressure but at risk for the presence of a leaking spinal defect or of a MM left unrepaired for more than 48 h.

Long-term results of the surgical treatment of craniopharyngioma: the experience at the Policlinico Gemelli, Catholic University, Rome

BackgroundCraniopharyngioma (CP) is the most common intracranial non-glial tumour observed in pediatric age. Although histologically benign and amenable to surgical treatment, its location and relation with vital nervous and vascular structures makes the feasibility of a radical resection difficult even in the microneurosurgery era. Beside the difficulties experienced when performing tumour resection, post-operative complications, such as endocrinological imbalance, represent another point that makes CP total excision a challenge. In order to avoid such complications, some authors have suggested to renounce to radical resection and to rely on post-operative radiation therapy to minimise the risk of residual tumour progression.MethodsWe report our experience with 52 children and adolescents operated on for CP at the Department of Pediatrics, Section of Pediatric Neurosurgery, Catholic University Medical School, Rome, between January 1985 and December 2002. The study included 14 children <5 years old (five less than 2 years of age), 25 between 6 and 10 years old, and 13 more than 10 years old. The most common presenting signs were related to endocrinological imbalance (35 cases), increased intracranial pressure (32 cases), and to a lesser extent, visual compromise (17 cases). Concerning location, CP was intrasellar in three cases; sellar/suprasellar with prominent prechiasmatic growth in 24 cases; retrochiasmatic/3rd ventricular in 14 cases, and giant (with an extension into the middle and/or posterior cranial fossae) in 11 cases. The tumour was managed by means of a single surgical approach in 47 cases and with a two-stage operation in the remaining five cases. In 11 cases of intrasellar or intra/suprasellar midline location, the first surgical approach was done through the transsphenoidal route (which represented the first step of a staged operation in five instances); in the remaining 41 patients, craniotomy was the first surgical procedure. Radical tumour resection was achieved in 40 cases, subtotal (only small tumour remnants adherent to the carotid arteries, 3rd ventricle floor or visual pathways) in nine, and only partial in the remaining three casesResultsHistology demonstrated the adamantinous variant in all cases. Two surgical deaths were recorded in this series (both following a transsphenoidal approach): one secondary to uncontrollable intra-operative bleeding from the carotid artery, and the other to fulminating bacterial meningoencephalitis. Morbidity included endocrinological disturbances, namely hypopituitarism and diabetes insipidus, in more than 80% of cases, worsening of pre-operative visual deficit in six cases, and transitory neurological deficits in five cases. One late death was recorded 2 years after surgery, secondary to electrolytic imbalance although favoured by a major head trauma with subacute subdural haematoma. Nine recurrences occurred 1–8 years after surgery (three true recurrences, and six re-growths of incompletely resected tumours) that required re-operation. Twelve patients underwent radiotherapy, six after an initially incomplete tumour resection and six following relapse. One patient presented with a malignant thalamic glioma 8 years after radiotherapy. At long-term follow-up, all survivors showed good clinical condition, even though approximately 60% relied on hormone replacement, and some patients presented obesity. Diabetes insipidus has subsided in about 80% of the cases; visual deficits improved or remained stable, whereas post-operative neurological deficits subsided in all but one patient.ConclusionIn our experience, radical resection of CP represented the first and almost unique treatment modality. Although not insignificant, post-operative mortality and morbidity do not seem to represent a major contraindication in attempting a radical tumour resection whenever possible. On the other hand, extensive hypothalamic involvement should suggest a less aggressive attitude.

Intracranial pressure monitoring in children with single suture and complex craniosynostosis : a review

IntroductionOne third of patients with craniofacial dysostosis syndromes and about 15–20% of children with single suture craniostenosis have a documented increase in intracranial pressure (ICP). The early detection of intracranial hypertension is important in order to reduce the risks for brain development and visual function. However, in children with craniosynostosis, the clinical manifestations of abnormally increased ICP are difficult to detect, as the majority of patients may have neither warning signs nor symptoms for a long period of time.Review Moreover, data from the literature suggest that neither fundoscopic nor radiological findings are necessarily related to intracranial pressure recordings in this type of pathology. In this context prolonged ICP monitoring seems actually to be the most valuable diagnostic tool. Extradural, subdural, and intraparenchymal devices have been used, and different softwares have been employed for PC storage and analysis of the data obtained. Most recent series consider mean ICP combined with plateaux waves as the most sensitive indicators in the final evaluation of the results. ConclusionsThe analysis of the literature demonstrates a significant difference in the prevalence of raised ICP preoperatively between non-syndromic and syndromic patients. Among the non-syndromic children, a direct relation between the number of sutures involved and raised ICP is documented. The analysis of plateaux waves seems to be particularly important in children with borderline mean ICP values. Persistent postoperative raised ICP has been described in 6–15% of patients with craniofacial dysostosis. It must be related to the multifactorial etiology of increased ICP in these patients, which includes cerebral venous congestion, upper airway obstruction, and hydrocephalus.

Communicating hydrocephalus induced by mechanically increased amplitude of the intraventricular cerebrospinal fluid pressure: Experimental studies

Abstract Acute and chronic hydrocephalus was induced in lambs by mechanically increasing the amplitude of the cerebrospinal fluid (CSF) intraventricular pulse pressure without modifying the mean CSF pressure and without interfering with CSF circulation or absorption. The characteristics of the hydrocephalus so obtained, namely, the asymmetry of ventricular dilation, the dilation of the distal portions of the ventricular system, and the absence of obstructions in CSF pathways, indicated a direct role of high-amplitude intraventricular CSF pulsations in the genesis of ventricular enlargement. As no impairment in CSF circulation or absorption was induced nor variations in CSF mean pressure, this experimental model is proposed as a model for communicating hydrocephalus.

Management of Recurrent Craniopharyngioma

SummaryAlthough histologically benign, craniopharyngioma can regrow either from macroscopic remnants of the tumour left behind at operation, or even after an apparently gross total removal. Recurrence rates vary significantly in the literature, depending on the efficacy of surgical treatment and also on the growth potential of the tumour itself. The main factor influencing tumour regrowth is obviously the extent of surgical resection, as total removal carries a much lesser risk of recurrence compared to subtotal or partial resections (although in such cases radiation therapy can lower this risk significantly). Other factors involved are the duration of follow-up and patients age at operation, as children tend to relapse more frequently than adults. Even in the “microsurgery” era, characterized by high percentages of total resections, recurrences remain high and continue to represent a major problem of craniopharyngioma treatment.Twenty-seven children and adolescents were operated on for craniopharyngioma at the Department of Neurosurgery, Section of Pediatric Neurosurgery, Catholic University Medical School, Rome, between June 1985 and June 1997. Total tumour resection was achieved in 18 cases, subtotal in 7 and partial 2 instances. One patient died post-operatively. Post-operative neuroradiological investigations confirmed the operative findings, although 3 children with an apparently gross total removal showed a residual non-enhancing calcium fleck adherent to the hypothalamus (which remained stable at the following examinations). Three of the 9 patients with less than total removal underwent post-operative radiation therapy. Out of the 26 surviving patients 6 presented a recurrence of their craniopharyngioma, 2 after an apparently gross total removal and 4 after a subtotal or partial resection (one of them had received radiation therapy). The diagnosis was merely neuroradiological in 5 cases, as only one child presented a clinical picture suggestive of tumour regrowth.Surgery was the first therapeutic option in all cases. Total tumour resection was accomplished in 3 cases, subtotal in 2 and partial in the last one. One child died post-operatively. Four of the 5 survivors received radiation therapy. All the patients are presently alive and stable (mean follow-up: 5.6 yrs). The authors conclude that surgery should be the first therapeutic option in case of recurrent craniopharyngioma and that radiation therapy should also be considered but only as adjuvant therapy.

Antibiotic impregnated external ventricular drainage and third ventriculostomy in the management of hydrocephalus associated with posterior cranial fossa tumours

BackgroundThe effectiveness of antibiotic pre-treated ventricular catheters in reducing the risk of CSF infections (determined on CSF cultures) resulting from the use of per-operative external ventricular drainages (EVD) and the success rate of post-operative endoscopic third ventriculostomy (ETV) in the management of persistent hydrocephalus after posterior cranial fossa tumour removal are assessed.MethodForty-seven children (group I) were prospectively managed by means of per-operative antibiotic impregnated EVD, post-operative ICP monitoring, and ETV. The results of this group were compared with those of a control group composed by 44 children treated with the same protocol as above except for the use of not-impregnated catheters (group II).FindingsThe rate of positive CSF cultures due to EVD resulted significantly lower in group I (2.1% vs 31.8%); there was no clinical evidence of CSF infections. The success rate of ETV was the same in both groups (75%). Failures of ETV occurred in the patients with subarachnoid tumour seeding and/or tumour extension to the basal cisterns. All the children of group II with failed ETV also showed a bacterial growth in the CSF.ConclusionsAntibiotic pre-treated catheters in our experience considerably limited EVD-related bacterial growth in the CSF. Preoperative hydrocephalus resolved in 60% of the cases after tumour removal, thus confirming recent data from the literature against the routine use of preoperative ETV. In our experience postoperative ETV had a high success rate; poor results were obtained in children with tumour seeding and/or the evidence of positive CSF cultures.

On the Pathology of Experimental Hydrocephalus Induced by Artificial Increase in Endoventricular CSF Pulse Pressure

In lambs, acute and chronic communicating hydrocephalus has been created by merely increasing the amplitude of the intraventricular cerebrospinal fluid (CSF) pulsations, leaving the mean CSF pressure unchanged. The pathologic changes occurring in this type of hydrocephalus do not differ qualitatively from those observed in obstructive hydrocephalus. Beside demonstrating a direct role of ventricular pulsations in the ventricular dilation, the observed findings indicate that an increase in mean CSF pressure is not a necessary condition for the occurrence of the hydrocephalus. Consequently, the hypothesis of abnormal high intraventricular CSF pressure oscillations at the basis of the ventricular dilation of normal pressure hydrocephalic patients, receives a significant support. Further support is provided is provided by considering the recorded experimental pathological lesions are quite similar to those observed in normal pressure hydrocephalic patients with patent subarachnoid CSF pathways.

Endoscopic third ventriculostomy: the best option in the treatment of persistent hydrocephalus after posterior cranial fossa tumour removal?

BackgroundTen to 40% of children operated on for a posterior fossa tumour require a further surgical procedure for the management of a persisting active ventricular dilation. The management of this kind of hydrocephalus is still controversial.ObjectiveTo prospectively evaluate the effectiveness of post-operative endoscopic third ventriculostomy (ETV) in the management of persistent active hydrocephalus in a series of children operated on for a posterior cranial fossa tumour.MethodsThe management protocol consisted of: (1) placement of a peri-operative antibiotic impregnated external ventricular catheter (Bactiseal®) and tumour removal, (2) post-operative intracranial pressure (ICP) monitoring through the external ventricular drainage, (3) ETV in case of persistent ventricular dilation and persistently abnormal high ICP values and (4) ventriculoperitoneal shunt implantation in case of ETV failure.ResultsThirty on a total of 104 children (28.8%) operated on between January 2001 and February 2007 at our institution needed a further surgical treatment for the persistence of the hydrocephalus after the removal of their posterior cranial fossa tumour. They were sub-divided in two groups according to the early (group 1—21 patients) or later (group 2—nine patients) definition of the persistence of an active ventricular dilation based on clinical, radiological and ICP monitoring data. ETV was successful in 90.0% of the patients in the present series (27/30 patients), without statistically significant differences among the two groups considered.ConclusionsPost-operative ETV should be considered the best option to treat persistent hydrocephalus after the removal of posterior fossa tumours.

Communicating hydrocephalus induced by mechanically increased amplitude of the intraventricular cerebrospinal fluid pulse pressure: Rationale and method

Abstract The effect of increasing the amplitude of the intraventricular cerebrospinal fluid (CSF) pulse pressure in lambs was studied in acute experiments. The intraventricular CSF pulse pressure was mechanically increased by a device which rhythmically inflated and deflated an intraventricular balloon synchronously with the cardiac rate. No variation in mean intraventricular CSF pressure was recorded following the increase in CSF pulse pressure. The neuropathological findings indicated a direct pathogenic effect on periventricular structures exerted by the intraventricular CSF pulsations, which were increased to three to six times the normal values.

Surgical Treatment of Chronic Subdural Hygromas in Infants and Children

Summary.Background: Extra-axial chronic fluid collections are pathological conditions occurring more frequently in the paediatric age, particularly in children less than two-year-old. Although recognised for many years and repeatedly reported in the literature, some aspects of their treatment are still under debate. This review of the management of chronic subdural collections is based on our experience of 72 cases treated between January 1984 and December 2000.Method: Patients were divided into four groups according to aetiology. Thirty-four cases (47%) occurred following various surgical procedures; 14 cases (20%) occurred as complications of leptomeningeal infections; 13 cases (18%) were post-traumatic, whereas no obvious aetiology could be detected in the last 11 cases (15%). The collections were unilateral in 34 patients (47%) and bilateral in the other 38 (53%).Findings: Thirty-five patients (48%) were treated by means of a temporary subdural external drainage (SED) (for a total of 38 SED procedures), which was maintained for a mean of 5.8 (±3.4) days; it was effective in 26 cases, whereas in the other 9 it was necessary to perform a subdural-peritoneostomy (SPS). Three of these 38 SEDs were complicated by infection. In one more child the external drainage was complicated by a chronic subdural haematoma. A SPS was performed in 44 cases (61%), 9 being failed external drainages. Only in 16 (38%) of these 44 patients the SPS was removed after an average of 27.0 (±16.6) months. Three patients (4%) were treated by craniotomy and resection of the neomembranes lining the subdural fluid collection. Obstruction of the SPS occurred in 6 children, infection in 4. Good results were obtained with either external or internal drainage. In fact post-operative neuroradiological investigation disclosed in all the cases complete or almost complete cerebral re-expansion; also the clinical outcome was generally very good, although largely dependent upon the basic clinical condition. Unilateral subdural-peritoneal and/or external drainage was effective also in case of bilateral collections. Only 2 patients required temporary bilateral external drainage.