Ventriculoperitoneal shunt block: what are the best predictive clinical indicators?

AIMS: To evaluate the predictive value of symptoms, signs, and radiographic findings accompanying presumed ventriculoperitoneal (VP) shunt malfunction, by comparing presentation with operative findings and subsequent clinical course. METHODS: Prospective study of all 53 patient referrals to a paediatric neurosurgical centre between April and November 1999 with a diagnosis of presumed shunt malfunction. Referral pattern, presenting symptoms and signs, results of computed tomography (CT) scanning, operative findings, and clinical outcome were recorded. Two patient groups were defined, one with proven shunt block, the other with presumed normal shunt function. Symptomatology, CT scan findings, and the subsequent clinical course for each group were then compared. RESULTS: Common presenting features were headache, drowsiness, and vomiting. CT scans were performed in all patients. Thirty seven had operatively proven shunt malfunction, of whom 34 had shunt block and three shunt infection; 84% with shunt block had increased ventricle size when compared with previous imaging. For the two patient groups (with and without shunt block), odds ratios with 95% confidence intervals on their presenting symptoms were headache 1.5 (0.27 to 10.9), vomiting 0.9 (0.25 to 3.65), drowsiness 10 (0.69 to 10.7), and fever 0.19 (0.03 to 6.95). Every patient with ventricular enlargement greater than their known baseline had a proven blocked shunt. CONCLUSIONS: Drowsiness is by far the best clinical predictor of VP shunt block. Headache and vomiting were less predictive of acute shunt block in this study. Wherever possible CT scan findings should be interpreted in the context of previous imaging. We would caution that not all cases of proven shunt blockage present with an increase in ventricle size.

Craniotomy-related complications in a paediatric neurosurgery unit--a prospective study.

A prospective study on four groups of children undergoing a craniotomy over a 6-month period was carried out in order to assess the incidence of complications. All complications were graded according to their severity and the requirement for extra general anaesthetics also recorded. From this information it is possible to calculate the resource implications of craniotomy-related complications in a paediatric neurosurgical unit, as well as point to those areas of clinical practice where improvements in technique are most needed.

The cervical spine in Crouzon syndrome.

STUDY DESIGN: All cervical spine radiographs of 44 patients with Crouzon syndrome treated at Great Ormond Street Hospital during the past 10 years were studied. OBJECTIVES: To assess the incidence and pattern of cervical spine abnormalities of patients with a confirmed diagnosis of Crouzon syndrome, but particularly regarding progressive fusion. SUMMARY OF BACKGROUND DATA: Previous studies into the cervical spine anomalies in those with Crouzon syndrome have shown an increased incidence of congenital abnormalities compared with the normal population. There is some suggestion from previous studies that cervical spine fusions are progressive in nature. METHODS: All radiographs were reviewed by the craniofacial team, along with a single pediatric radiologist with experience in assessment of skeletal dysplasias. RESULTS: Radiologic abnormalities included "butterfly" vertebrae and fusions of the bodies and the posterior elements. Evidence of fusion was present in eight of 44 (18%) of patients. C2-C3 and C5-C6 were almost equally affected. Block fusions involving multiple vertebrae were seen. Analysis of sequential studies in 16 patients showed evidence of progression in five. CONCLUSIONS: These results reveal an incidence of fusions that is lower than reported previously. There is radiologic evidence from serial studies that the fusions are progressive, and because these patients are children, the fusion process may not be complete, which may account for the lower incidence of fusions than in previous studies. The pattern of fusions is different from that in earlier studies, which may be a result of the method of diagnosis because this population is less likely to include atypical forms of other syndromes (which have a higher incidence of cervical fusions, particularly at C2-C3). Regarding other congenital anomalies, it appears that butterfly vertebrae are especially prevalent in association with Crouzon syndrome.

Anomalous venous drainage in a case of non-syndromic craniosynostosis.

The authors describe the clinical and radiological findings in a case of non-syndromic craniosynostosis affecting multiple sutures, in which the intracranial venous drainage was grossly anomalous. Investigation by magnetic resonance imaging and angiography revealed that almost all of the intracranial venous blood was draining from the dural sinuses transosseoussly via enlarged emissary veins to the external jugular veins and the vertebral veins. Although present, both internal jugular veins were small. This discovery represented a contraindication for the vault expansion surgery that had been recommended as treatment for the patient's raised intracranial pressure, and it has important implications for the management of all types of craniosynostosis.

The cervical spine in Saethre-Chotzen syndrome.

Twenty patients with a diagnosis of Saethre-Chotzen syndrome had their cervical spine radiographs reviewed. Radiologic abnormalities including vertebral fusion were present in 9 of the 20 patients. Fusion of both the vertebral bodies and the posterior elements was noted, although the latter site was more common. C2-3 was the level most commonly involved, although other levels were recorded. Analysis of sequential radiographs in nine patients revealed evidence of progression in seven patients. In those studies in children aged under 2 years, only 1 of 18 films showed evidence of fusion, while in those over 2 years of age, 10 of 12 showed evidence of fusion. These results reveal that the incidence of cervical anomalies in Saethre-Chotzen syndrome is greater than that in the general population. There is both direct and indirect evidence that the vertebral fusions are progressive during childhood.

Lessons from a case of kleeblattschädel. Case report.

The authors describe the clinical, radiological, and postmortem findings of a case of cloverleaf skull syndrome. The presence of hindbrain herniation, abnormal cervical segmentation, and atlantoaxial subluxation illustrate the anatomical complexity of the skull base and the craniocervical junction that may coexist in this condition. Unavoidable division of occipital emissary veins during elevation of the skin flap at the time of vault remodeling surgery led to an acute and, ultimately, fatal rise in intracranial pressure. Postmortem examination and review of magnetic resonance imaging revealed an anomalous pattern of venous drainage of the intracranial structures that appeared to have developed in response to venous obstruction, secondary to intraosseous venous sinuses and stenosis of the jugular foramina. The relationship between venous hypertension, hindbrain herniation, and hydrocephalus in this situation is reviewed, and the implications for evaluation and management of this vexing disorder are discussed.

Intracranial pressure in single-suture craniosynostosis.

The indications for surgical correction of craniosynostosis in which there is involvement of only one of the cranial vault sutures have traditionally been based upon the cosmetic merits of the deformity alone. Whilst it is now appreciated that intracranial hypertension is commonly associated with the more complex forms of craniosynostosis, this aspect has not previously been addressed in detail among cases of single-suture craniosynostosis. This retrospective study reports our experience of overnight subdural intracranial pressure monitoring in 74 children with premature closure of a single cranial suture. A single coronal suture was involved in 37 patients, the sagittal suture in 25 and the metopic suture in 12. Intracranial pressure was raised in 13 (17%), borderline in 28 (38%) and normal in 33 (45%). Elevated intracranial pressure was seen more commonly where a midline suture was involved (sagittal or metopic) than when a single coronal suture was fused. We conclude that intracranial hypertension occurs in a significant proportion of children with single-suture craniosynostosis and suggest that this factor should be borne in mind during the initial assessment of these children so as to enable timely intervention where required and appropriate counselling of parents.