Marie-Lise C. van Veelen

Cognitive Deficits and Predictors 3 Years After Diagnosis of a Pilocytic Astrocytoma in Childhood

PURPOSE To prospectively study cognitive deficits and predictors 3 years after diagnosis in a large series of pediatric patients treated for pilocytic astrocytoma (PA). PATIENTS AND METHODS Sixty-one of 67 children were grouped according to infratentorial, supratentorial midline, and supratentorial hemispheric site. Intelligence, memory, attention, language, visual-spatial, and executive functions were assessed. Included predictors were sex, age, relapse, diagnosis-assessment interval, hydrocephalus, kind of treatment, and tumor variables. Results All children with PA had problems with sustained attention and speed. In the infratentorial group, there also were deficits in verbal intelligence, visual-spatial memory, executive functioning, and naming. Verbal intelligence and verbal memory problems occurred in the brainstem tumor group. The supratentorial hemispheric tumor group had additional problems with selective attention and executive functioning, and the supratentorial midline tumor group displayed no extra impairments. More specifically, the dorsal supratentorial midline tumor group displayed problems with language and verbal memory. Predictors for lower cognitive functioning were hydrocephalus, radiotherapy, residual tumor size, and age; predictors for better functioning were chemotherapy or treatment of hydrocephalus. Almost 60% of children had problems with academic achievement, for which risk factors were relapse and younger age at diagnosis. CONCLUSION Despite normal intelligence at long-term follow-up, children treated for PA display invalidating cognitive impairments. Adequate treatment of hydrocephalus is important for a more favorable long-term cognitive outcome. Even children without initial severe deficits may develop cognitive impairments years after diagnosis, partly because of the phenomenon of growing into deficit, which has devastating implications for academic achievement and quality of life (QOL).

Algorithm for the management of intracranial hypertension in children with syndromic craniosynostosis

Background: The purpose of this study was to examine the relationship of head growth, obstructive sleep apnea, and intracranial hypertension in patients with syndromic or complex craniosynostosis, and to evaluate the authors’ standardized treatment protocol for the management of intracranial hypertension in these patients. Methods: The authors conducted a prospective observational cohort study of patients with syndromic craniosynostosis at a national referral center, treated according to a standardized protocol. Measurements included occipitofrontal head circumference, with growth arrest defined as downward deflection in occipitofrontal head circumference trajectory greater than or equal to a 0.5 SD fall from baseline over 2 years, or lack of change in occipitofrontal head circumference growth curve; sleep studies, with results dichotomized into no/mild versus moderate/severe obstructive sleep apnea; and funduscopy to indicate papilledema, supplemented by optical coherence tomography and/or intracranial pressure monitoring to identify intracranial hypertension. Results: The authors included 62 patients, of whom 21 (33.9 percent) had intracranial hypertension, 39 (62.9 percent) had obstructive sleep apnea, and 20 (32.3 percent) had occipitofrontal head circumference growth arrest during the study. Age at which intracranial hypertension first occurred was 2.0 years (range, 0.4 to 6.0 years). Preoperatively, 13 patients (21.0 percent) had intracranial hypertension, which was associated only with moderate/severe obstructive sleep apnea (p = 0.012). In the first year after surgery, intracranial hypertension was particularly related to occipitofrontal head circumference growth arrest (p = 0.006). Beyond 1 year after surgery, intracranial hypertension was associated with a combination of occipitofrontal head circumference growth arrest (p < 0.001) and moderate/severe obstructive sleep apnea (p = 0.007). Conclusions: Children with syndromic craniosynostosis are at risk of intracranial hypertension. The major determinant of this after vault expansion is impaired head growth, which may occur at varying ages. The presence of moderate/severe obstructive sleep apnea also significantly increases the risk of intracranial hypertension. CLINICIAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Are ultrasonography measurements of optic nerve sheath diameter an alternative to funduscopy in children with syndromic craniosynostosis

OBJECT Children with syndromic or complex craniosynostosis are evaluated for increased intracranial pressure (ICP) using funduscopy to detect papilledema. However, papilledema is a late sign of increased ICP. Because papilledema might be preceded by an increase in optic nerve sheath (ONS) diameter, the authors conducted a prospective study to establish the validity and applicability of measuring the ONS using ultrasonography. METHODS From January 2007 to December 2009, 175 bilateral ultrasonography ONS measurements were performed in 128 patients with syndromic or complex craniosynostosis during the daytime. The measurements were correlated with ONS diameter assessed on CT and simultaneous funduscopy, when available. Furthermore, results were compared by using thresholds for ONS diameters on ultrasonography that are available in the literature. RESULTS The mean ONS diameter on ultrasonography was 3.1 ± 0.5 mm. The CT measurement was significantly correlated with the ultrasonography measurement (r = 0.41, p < 0.001). The mean ONS diameter in 38 eyes with papilledema was 3.3 ± 0.5 mm, compared with 3.1 ± 0.5 mm in the eyes of patients without papilledema (p = 0.039). Relative to the age-related thresholds, the ONS diameter was too large in 11 eyes (3%), particularly in patients with Crouzon syndrome. Compared with funduscopy, ultrasonography sensitivity was 11%, specificity was 97%, and positive and negative predictive values were 40% and 86%, respectively. CONCLUSIONS Ultrasonography is a valid and easy way of quantifying the ONS. Although the ONS diameter is larger in children with papilledema, it cannot be used as a daytime screening tool instead of funduscopy. The ONS diameter is possibly a more real-time indicator of ICP.

Internal carotid dissection after Le Fort III distraction in Apert syndrome: A case report

A 10-year-old girl with Apert syndrome underwent a Le Fort III osteotomy with the positioning of internal and external distraction devices. The operation was straightforward with no intraoperative complications. Very soon after completion of surgery an anisocoria (unilateral dilation of a pupil) was noticed. This was followed by intracranial oedema which was fatal. The aetiology was dissection of the right internal carotid artery is reported. The complications of Le Fort osteotomies are discussed regarding patients with complex syndromal craniosynostosis and midface hypoplasia, such as Apert syndrome.

Venous hypertension in syndromic and complex craniosynostosis: The abnormal anatomy of the jugular foramen and collaterals *

UNLABELLED Why craniosynostosis patients develop elevated intracranial pressure (ICP) is still a mystery. Our aim was to investigate jugular foramen size and its relation to venous hypertension and elevated ICP. Secondly, we evaluated whether occipital collateral veins develop as a compensatory mechanism for elevated ICP. We conducted a prospective study in 41 children with craniosynostosis who underwent a 3D-CT-angiography. We evaluated the anatomical course of the jugular vein, the diameter of the jugular foramen and the relation to the presence of papilledema. Additionally, we studied the anatomical variations of the cerebral venous drainage system. The diameter of the jugular foramen was significantly smaller in our patients. Abnormal venous collaterals were most often observed in patients with Apert, Crouzon-Pfeiffer and Saethre-Chotzen syndrome, even in children under two years of age. There was no significant difference in the number of collateral veins in patients with or without papilledema. Collaterals appear to reflect an inborn abnormality of the venous system, rather than a compensating mechanism for elevated ICP. This study confirms the presence of jugular foraminal narrowing in craniosynostosis patients and an abnormal venous system, which may predispose to elevated ICP. LEVEL OF EVIDENCE Diagnostic II.

Assessment of White Matter Microstructural Integrity in Children with Syndromic Craniosynostosis: A Diffusion-Tensor Imaging Study

PURPOSE To assess whether architectural alterations exist in the white matter of patients with syndromic and complex craniosynostosis. MATERIALS AND METHODS The medical ethics committee approved this study. Written informed consent was obtained from parents or guardians before imaging. A prospective study was performed in children with syndromic and complex craniosynostosis aged 6-14 years. Forty-five patients were included: four had Apert syndrome, 14 had Crouzon-Pfeiffer syndrome, eight had Muenke syndrome, 11 had Saethre-Chotzen syndrome, and eight had complex craniosynostosis. In addition, seven control subjects were evaluated. For diffusion-tensor imaging, an echo-planar sequence was used with a diffusion gradient (b = 1000 sec/mm(2)) applied in 25 noncollinear directions. Regions of interest (ROIs) were placed in the following white matter structures: pontine crossing tract, corticospinal tracts, medial cerebral peduncles, uncinate fasciculus (measured bilaterally), anterior commissure, frontal and occipital white matter (measured bilaterally), fornix, corpus callosum (measured in the genu and splenium), and corpus cingulum (measured bilaterally). Eigenvalues were measured in all ROIs and fractional anisotropy (FA) was calculated. RESULTS Across all measured ROIs, FA values were generally lower in all patients combined than in the control subjects (P < .001). There were no significant differences among subgroups of patients. CONCLUSION Diffusion-tensor imaging measurements of white matter tracts reveal significant white matter integrity differences between children with craniosynostosis and healthy control subjects. This could imply that the developmental delays seen in these patients could be caused by the presence of a primary disorder of the white matter microarchitecture.

Foramen magnum size and involvement of its intraoccipital synchondroses in Crouzon syndrome.

Background: Cranial sutures and synchondroses tend to close prematurely in patients with Crouzon syndrome. This influences their skull vault and skull base development and may involve in common disturbances such as increased intracranial pressure and cerebellar tonsillar herniation. The authors’ hypothesis was that Crouzon patients patients have a smaller foramen magnum than controls because of premature fusion of the intraoccipital synchondroses, putting them at risk for cerebellar tonsillar herniation. Therefore, foramen magnum size and time of intraoccipital synchondroses closure were evaluated and were related to the presence and degree of cerebellar tonsillar herniation. Methods: The foramen magnum surface area and anteroposterior diameter were measured on three-dimensional computed tomographic scans of 27 Crouzon patients and 27 age-matched controls. Scans had a slice-thickness between 0.75 and 1.25 mm and were aligned in a three-dimensional reformatting platform. The t test was used to study size differences. Synchondroses were graded as described by Madeline and Elster and studied with ordinal logistic regression analysis. Results: Crouzon patients had a smaller foramen magnum surface area (602 mm2 versus 767 mm2, p < 0.001) and anteroposterior diameter (31 mm versus 35 mm, p < 0.001) compared with controls. Differences stayed constant over time. Intraoccipital synchondroses closed 3 to 9 months earlier in Crouzon patients than in controls (p < 0.05). Conclusions: Since intraoccipital synchondroses close earlier in Crouzon patients, from early life on their foramen magnum is smaller compared with controls. Within Crouzon patients, the presence of cerebellar tonsillar herniation could not be related to foramen magnum size. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Does early resection of presumed low-grade glioma improve survival? A clinical perspective

Early resection is standard of care for presumed low-grade gliomas. This is based on studies including only tumors that were post-surgically confirmed as low-grade glioma. Unfortunately this does not represent the clinicians’ situation wherein he/she has to deal with a lesion on MRI that is suspect for low-grade glioma (i.e. without prior knowledge on the histological diagnosis). We therefore aimed to determine the optimal initial strategy for patients with a lesion suspect for low-grade glioma, but not histologically proven yet. We retrospectively identified 150 patients with a resectable presumed low-grade-glioma and who were otherwise in good clinical condition. In this cohort we compared overall survival between three types of initital treatment strategy: a wait-and-scan approach (n = 38), early resection (n = 83), or biopsy for histopathological verification (n = 29). In multivariate analysis, no difference was observed in overall survival for early resection compared to wait-and-scan: hazard ratio of 0.92 (95% CI 0.43–2.01; p = 0.85). However, biopsy strategy showed a shorter overall survival compared to wait-and-scan: hazard ratio of 2.69 (95% CI 1.19–6.06; p = 0.02). In this cohort we failed to confirm superiority of early resection over a wait-and-scan approach in terms of overall survival, though longer follow-up is required for final conclusion. Biopsy was associated with shorter overall survival.

Frontobiparietal remodeling with or without a widening bridge for sagittal synostosis: comparison of 2 cohorts for aesthetic and functional outcome

OBJECT Various techniques to correct sagittal synostosis have been described. The authors of this study assess the results of 2 techniques for late complete cranial remodeling and test the hypothesis that adding a widening bridge would improve outcome. METHODS In this retrospective study, the authors evaluated patients with nonsyndromic sagittal synostosis-those who underwent frontobiparietal remodeling (FBR) and those who underwent modified FBR (MFBR) involving the introduction of a bony bridge to increase the width of the skull. Outcomes for both groups are described in terms of the aesthetic results assessed on photographs and any changes in the cranial index (CI) and head circumference over time, the presence of papilledema, and complaints of headache. The effect of the surgical technique on CI and head circumference over time was assessed using linear regression analysis, with adjustment for preoperative CI and head circumference. RESULTS Sixty-nine patients with isolated sagittal synostosis were included in this study: 35 underwent MFBR and 34 underwent the original technique of FBR. The mean follow-up period was 7 years. In the 1st year after surgery, mean CI improved by 9% in the FBR group and by 12% in the MFBR group. One year after surgery, CI in the MFBR group was on average 4.7% higher than that in the FBR group (p < 0.001). During follow-up, CI decreased in both groups; however, at all time points CI was significantly higher in the MFBR group than in the FBR group. The impact of surgical technique on CI was less important than the impact of preoperative CI (R(2)= 0.26 vs 0.54), and this applied at all time points during follow-up. Head circumference declined during follow-up in both groups. It was influenced by preoperative head circumference, but not by surgical technique. Aesthetic outcome, prevalence of headache (42%), and papilledema (7%) were comparable in both groups. CONCLUSIONS Adding a widening bridge to late complete remodeling significantly improved CI and helped to prevent CI from decreasing in the long term. This addition did not affect the head circumference growth curve. Despite a mean head circumference remaining at +1 SD, patients continued to develop papilledema postoperatively (7%).

A novel mutation in FGFR2

Craniosynostosis is a congenital anomaly that can occur as an isolated condition or as part of a syndrome. Although several genes are known to cause syndromic craniosynostosis, only 24% can be attributed to known genes. Therefore, it is likely that more mutations and other genes are involved. We present the identification of a novel point mutation in fibroblast growth factor receptor 2 (FGFR2), c.812G>T, p.(Gly271Val) or c.1851G>C, p.(Leu617Phe). Furthermore, we describe a mutation that has been identified just recently, c.812G>T, (p.Gly271Val) or c.1851G>C, (p.Leu617Phe). In addition, we describe findings from a sequence analysis of all coding exons and exon/intron boundaries of FGFR2 performed on 124 patients with syndromic craniosynostosis.