Unilateral abducens and bilateral facial nerve palsies associated with posterior fossa exploration surgery.

Multiple cranial nerves palsies following a posterior fossa exploration confined to an extradural compartment is a rare clinical presentation. This case report describes a young man who developed a unilateral abducens and bilateral facial nerve palsies following a posterior fossa exploration confined to an extradural compartment. There are different theories to explain this presentation, but the exact mechanism remains unclear. We propose that this patient cranial nerve palsies developed following cerebrospinal fluid (CSF) leak, potentially as a consequence of rapid change in CSF dynamics.

Routine cerebrospinal fluid analysis during 'de novo' ventriculoperitoneal shunt insertion: Single Institution Experience.

Background Cerebrospinal fluid (CSF) sampling is performed during ventriculoperitoneal (VP) shunting procedure surgery for early detection of infection. We have performed a retrospective study to determine whether routine intraoperative CSF sampling at new VP shunt insertion has predicted shunt infection or changed subsequent surveillance or management. Method From January 2011 to December 2013, 99 patients underwent first time VP shunt insertion at our hospital. The data collected from Beaumont Hospital Information System and operating theatre logbook. The reviewed data were patient demographics, the clinical condition requiring VP shunt procedure, shunt type, date of VP shunt insertion, date of VP shunt infection or malfunction and laboratory data. Results A first time VP shunt insertion procedure was performed in 99 patients. During the VP shunt insertion procedure, 64 patients had CSF sampling for microbiological analysis. The CSF culture was negative in all samples. All patients were followed up for 12 months. During the follow-up period, a total of 15 patients underwent VP shunt revision. Three of the shunt revisions were secondary to infection. The three infected shunt cases had sterile CSF cultures at the time of insertion. Conclusion There appears to be no correlation between CSF sampling during first time VP shunt insertion and the later development VP shunt infection. This questions the need for routine CSF sampling at the time of insertion. This would be confirmed as a part of future randomised trials.

Holoprosencephaly: antenatal and postnatal diagnosis and outcome.

OBJECTIVES: The objectives of this study are to ascertain the clinical outcome and overall survival of holoprosencephaly (HPE) patients diagnosed antenatally and postnatally, to determine the accuracy of antenatal diagnosis and to determine the role of neurosurgical intervention in HPE. DESIGN: This is a retrospective review over a 10-year period. PATIENTS: Sixty-three patients were included in the study, 45 were diagnosed by antenatal radiological imaging and 18 were diagnosed by postnatal radiological imaging. Patient data was drawn from Temple Street Children's University Hospital (the national paediatric neurosurgery centre), the National Maternity Hospital in Holle's Street, Dublin, and Our Lady of Sick Children Hospital, Dublin. METHODS: The study was carried out through a review of antenatal and postnatal radiological imaging and reports, clinical charts, GP letters from patient follow-up and telephone conversations with parents of HPE patients. RESULTS: Four patients in the antenatal diagnosis group had follow-up foetal MRI confirming HPE. Twelve in this group had radiological follow-up postnatally, and in five of these, HPE was confirmed. The remaining seven were identified as false positive. Alobar HPE constituted 55 % (21/38) of patients with 95 % mortality. Fifty-one percent had a normal karyotype. The overall survival in the antenatal diagnosis group was 13 %. In the postnatal group, 18 patients were identified, 67 % (12/18) lobar and 33 % (6/18) semilobar. Normal karyotype was found in 72 % (13/18), with an overall survival rate of 56 % (10/18). Neurosurgical intervention in both groups mainly consisted of CSF diversion in the form of ventriculoperitoneal (VP) or cystoperitoneal shunt (CP) (13/67). CONCLUSION: Foetal MRI should be routinely performed in suspected cases of HPE, and reliance on ultrasound alone in the antenatal period may not be sufficient. In our study, there is a high early mortality noted in severe cases of HPE, while milder forms of HPE in children tend to survive beyond infancy albeit with associated complications that required neurosurgical intervention and medical management for other associated systemic anomalies.

Suprasellar pilocytic astrocytoma: one national centre's experience.

INTRODUCTION: Pilocytic astrocytomas in the supratentorial compartment make up 20 % of all brain tumours in children with only 5 % of these arising in the suprasellar region. Optic pathway gliomas or suprasellar gliomas are often seen in neurofibromatosis type 1 (NF1) patients. Given their location, suprasellar pilocytic astrocytomas are challenging to manage surgically with high morbidity rates from surgical resection. We assess our cohort of patients with suprasellar pilocytic astrocytoma and document our experience. METHOD: A retrospective review of patients diagnosed with suprasellar glioma between 2000-October 2012. We included patients diagnosed with optic pathway glioma based on radiological features (with or without biopsy) and those who had a biopsy confirming pilocytic astrocytoma. RESULTS: Fifty-three patients included (sporadic tumours 24 and NF1 related 29). Fifteen sporadic and four NF1 patients were biopsied. Twelve sporadic and 13 NF1 patients were initially treated with chemotherapy while only 1 patient had radiotherapy initially. Progression was noted in 58 % of the sporadic group and 24 % of the NF1 group. The only significant factor for progression was NF1 status (p = 0.026). CONCLUSION: Management should be guided by individual patient circumstance. In our cohort, chemotherapy did not significantly improve progression free survival; however, NF1 status significantly correlated with the decreased progression.

ETV as a last resort.

INTRODUCTION: The field of neuroendoscopy is rapidly expanding with increasing indications for endoscopic third ventriculostomy (ETV). DISCUSSION: As a treatment for hydrocephalus, ETV has the advantage of providing a more physiological cerebrospinal fluid diversion without shunt hardware which reduces the risk of recurrent infection and malfunction. The success rate of ETV has been increasing with decreasing morbidity and mortality. CONCLUSION: Originally, ETV was indicated for cases of obstructive hydrocephalus, however the indications are expanding. To highlight this, we present a small series of cases were ETV is not traditionally indicated and was a treatment of last choice.

Routine preoperative blood testing in pediatric neurosurgery.

OBJECT: The frequency with which routine preoperative blood test results predict perioperative or postoperative complications is insignificant. The unnecessary ordering of routine tests increases the financial costs and patients' distress. The authors evaluated the effects of routine preoperative testing on patient management and the overall financial costs. METHODS: The authors retrospectively reviewed the medical records and laboratory data for 355 children admitted to the neurosurgical department for elective procedures over a 5-year period (January 2008-December 2012). They excluded all patients admitted for imaging or surgical procedures requiring local anesthesia, and they recorded the results of preoperative and previous (up to 6 months before surgery) blood tests and any abnormalities noted. RESULTS: As a result of the 3489 blood tests ordered preoperatively for 328 (94.6%) of the 355 patients, 29 abnormalities (9%) were detected. Most of these abnormal values were near the reference range, and none significantly affected the progression of scheduled procedures. For only 1 patient (0.28%) was the procedure cancelled because of an abnormality (preoperative partial thromboplastin time), which further testing showed to be a false-positive result. The cost of these tests over 5 years was 5205-10,410 euros ($6766-$13,533 US). CONCLUSIONS: Preoperative tests should be selectively requested on the basis of clinical indication.

Central brain herniation in shunted Dandy Walker cyst.

INTRODUCTION: Dandy-Walker Syndrome (DWS) is a constellation of congenital anomalies of the central nervous system consisting of cerebellar vermis hypoplasia or agenesis, cystic dilatation of the fourth ventricle, enlarged posterior fossa, and a high tentorium. Hydrocephalus is a common occurrence in DWS and its treatment varies between shunting-ventriculoperitoneal or cystoperitoneal or both, endoscopic cyst fenestration, and third ventriculostomy. Chronic cerebral herniation is a known complication of treatment in DWS; however, we present an unusual case of central brain herniation. CASE REPORT: A 2 year old boy with shunted DWS presented with status epilepticus. Initial CT brain scan showed no increase in ventricle or cyst size; however, tapping the shunt reservoir did not yield any CSF prompting a shunt revision. Postoperatively, he was very slow to wake and subsequently experienced an episode of fixed pupils and extensor posturing. MRI brain demonstrated severe herniation of both thalami through the tentorium. CONCLUSION: This child had chronic central brain herniation (CCBH) secondary to the shunting of his cyst. To our knowledge, this is the first case of CCBH following treatment of DW cyst.

The open fontanelle: a window to less radiation.

INTRODUCTION: Over the years, there has been increasing awareness of the radiation doses from medical investigation and treatment modalities and the long-term effect of this radiation. In no other patient population is this more of an issue than in the paediatric population who are more radiosensitive and have a longer life span in which to express any negative effects of radiation. In children under the age of one, the anterior fontanelle is an acoustic window to intracranial structures allowing for the use of cranial ultrasound (CRUSS) instead of CT. AIM: To determine the pattern of CT and Cranial ultrasound used in patients aged one or younger with shunt treated hydrocephalus. METHODS: A retrospective review of patients who had a shunt inserted before the age of one and their imaging. Effective radiation doses were calculated for those who had CT scans. RESULTS: One hundred thirty-five patients were included with 227 CTs and 124 CRUSS conducted. In the follow-up period after shunt insertion, 92 patients had CTs while 14 were followed with CRUSS and 51 patients required a shunt revision before the age of one. The average effective radiation dose per scan was 2.76 mSv. CONCLUSION: Children with an open fontanelle and shunt can be followed reliably with CRUSS in order to reduce their exposure to radiation.