A retrospective analysis of emergency referrals and admissions to a regional neurosurgical centre 2016-2018.

BACKGROUND AND OBJECTIVES: Emergencies account for 60% of UK neurosurgical workload. We analysed the emergency referrals made to the on-call neurosurgical registrar in a regional centre over three years, aiming to identify temporal trends in volume of referrals, admission practices and major diagnostic categories contributing to referrals and admissions. METHODS: Individual referrals recorded in on-call databases were processed to extract basic demographics, call timing, diagnosis category and whether the patient was admitted under neurosurgery. Linear regression analysis was used to identify temporal trends across the three years. RESULTS: A total of 18128 calls were made to the on-call registrar between 2016 and 2018, with a significant increase in monthly calls. On average, one call was received every 88 minutes. An increasing proportion of these calls were taken out of office hours. Diagnostic categories accounting for the largest percentage of calls were traumatic brain injury (17.7%) and cauda equina syndrome (13%). Significant increases in referral volume were seen in cauda equina syndrome, traumatic brain injury, spinal trauma and spinal tumours, while no category had a significant decrease. The admission rate was 17.1% - no change was seen in this across the study period, resulting in increasing numbers of admissions, reflecting increasing referrals. Categories most likely to result in admission were hydrocephalus (41.1%), spontaneous subarachnoid haemorrhage (39.4%), intracranial infection (32.6%) and chronic subdural haematoma (CSDH, 32.2%). A change in admission rate was seen only for CSDH, with a significant increase in the percentage of referrals across the study period. CONCLUSION: Emergency neurosurgical referrals continue to rise in the UK at a rate exceeding population growth. This implies a decreasing referral threshold. However, the constant admission rate suggests either an increasing amount of neurosurgical pathology, the threshold for admission/intervention has decreased, or a combination. Neurosurgical services need to adapt in order to meet increasing demands.

The Prevalence of Cerebrovascular Abnormalities Detected in Various Diagnostic Subgroups of Spontaneous Subarachnoid Hemorrhage in the Modern Era.

OBJECTIVE: To determine prevalence of cerebrovascular abnormalities in diagnostic subgroups of spontaneous subarachnoid hemorrhage (SAH) in a regional neurosurgical center in the modern era. METHODS: Data of 609 consecutive patients with spontaneous SAH in a 3-year period (August 2010 to August 2013) were prospectively collected. Patients were divided into 3 diagnostic subgroups: computed tomography (CT) positive for SAH; CT negative but positive cerebrospinal fluid examination by spectrophotometry for SAH; CT negative for SAH and inconclusive cerebrospinal fluid examination. All patients fit for intervention underwent CT angiography with or without digital subtraction angiography to identify vascular abnormalities for subsequent treatment. RESULTS: Of 609 patients, 554 were fit for further investigation and consideration of further intervention; 514 patients had confirmed SAH. Mean patient age was 54.0 years; 61.5% of patients were women. Of patients, 390 (75.9%) showed vascular abnormalities on angiography. There were 438 patients (85.2%) with confirmed SAH diagnosed on CT scan (group 1). Vascular abnormalities were detected in 81.1% of patients; 18.9% of patients with positive CT scan had no identifiable cause of SAH. Of patients with confirmed SAH, 76 (14.8%) had negative CT scan but positive lumbar puncture (group 2); 46.1% of patients in this group had vascular abnormalities. Three patients with inconclusive cerebrospinal fluid examination had lesions requiring treatment. Median length of hospital stay in group 1 patients was longer than median length of hospital stay in group 2 patients. CONCLUSIONS: Frequency of vascular abnormalities in spontaneous SAH is lower than the traditionally quoted figure, which has diagnostic and prognostic implications for patient management.

Post-operative cyclizine misuse.

Cyclizine is commonly prescribed as an anti-emetic post-operatively. We report a case of a 51-year-old woman who developed addiction to intravenous cyclizine following regular administration at recommended doses. This is the first report of cyclizine misuse post-operatively. We compare this case to cyclizine abuse reported amongst other populations. Prescribers should be aware of the potential of cyclizine as a drug of abuse.

Time to diagnosis of paediatric posterior fossa tumours: an 11-year West of Scotland experience 2000-2011.

INTRODUCTION: Brain tumours are the most common solid childhood malignancy accounting for 20% of all paediatric cancers. Of these, posterior fossa tumours comprise approximately 60-70% of all brain tumours in children. Several studies have estimated the median pre-diagnostic interval (PSI) of paediatric brain tumours as approximately 60 days. OBJECTIVES: The objectives of this retrospective analysis were to (a) identify the common presenting symptoms of posterior fossa tumours, (b) determine the time interval from the first attributable symptom to the radiological diagnosis of a posterior fossa tumour, (c) compare the West of Scotland with other international centres and (d) identify which factors correlate with outcome for these children. MATERIALS AND METHODS: A retrospective case note review of 69 children diagnosed with posterior fossa tumours from January 2000 to September 2011. Of the 69 children diagnosed during this period, complete data were available for 66 children (M:F = 31:35, Mean age (SD): 7.50 + 4.53 years). Results. Nausea and vomiting (75.8%), headaches (63.6%) and incoordination (51.5%) were recorded as the most common presenting symptoms followed by lethargy (28.8%), cranial nerve palsy (25.8%) and diplopia (24.2%). Fifty-three of the sixty-six children (i.e., 80.3%) demonstrated radiological evidence of hydrocephalus on their initial scan. The majority of children were assessed by less than three specialists after a median PSI of 43.5 days. The only variable significantly associated with PSI was tumour grade (r = - 0.202, p = 0.036). Neither age at diagnosis, number of specialists seen, nor outcome was significantly correlated with PSI. The only factor associated with outcome was tumour grade (r = 0.337, p = 0.006). CONCLUSION: Despite recent reports indicating poor performance of the UK with respect to time to diagnosis of paediatric brain tumours, the present data indicate that the experience of this cohort is favourably comparable to international standards.

Paediatric head injury admissions over a 10-year period in a regional neurosurgical unit.

Traumatic brain injury is a leading cause of death and disability in childhood. A retrospective study of all paediatric head injuries admitted to the neurosurgical unit for the West of Scotland over a 10-year period was performed to assess the impact of the National Institute for Health and Clinical Excellence head injury guidelines on the admission rate and to determine the associated risk factors, causes, severity and outcomes of these injuries. There were 564 admissions between 1998 and 2007. The median age at presentation was nine years and two months. There was no change in the admission rate, injury mechanism or severity of head injury admitted over the period studied. A relationship was observed between the Scottish Index of Multiple Deprivation Score and the incidence of head injury (P = 0.05). Alcohol was reported as a causative factor in only a small number of cases, and moderate to severe head injuries were more commonly identified as a result of road traffic accidents.

Primary intracranial leiomyosarcoma: a case report and review of the literature.

INTRODUCTION: Malignant tumours of the central nervous system (CNS) represent the second most common cancer type in the paediatric population of developed countries, and mortality caused by CNS tumours is the highest among paediatric cancers. Tumours of mesenchymal origin occurring either as primary or secondary lesions of the central nervous system are very rare in children. This paper describes the case of a 5-year-old non-immunocompromised male who presented with a right frontal primary intracranial leiomyosarcoma associated with large subdural collections. DISCUSSION AND CONCLUSION: Following surgical excision and adjuvant chemoradiotherapy, the patient has remained disease-free for 18 months. The literature is reviewed and the possible association of the chronic subdurals to the later development of the leiomyosarcoma explored.

Infantile clivus chordoma without clivus involvement: case report and review of the literature.

BACKGROUND: We present a giant clival chordoma with disseminated disease but without involvement of the clivus. To our knowledge, this is the youngest child and only the second case, presenting without base of skull involvement, in paediatric literature and the fourth reported case of a chordoma in a patient with tuberous sclerosis. DISCUSSION: We discuss the subtle presentation, difficulties in diagnosis and management and also review the literature.

Stereotactic biopsy of brain tumours in the paediatric population.

OBJECTIVE: Our objective was to establish the role of stereotactic neurosurgical techniques in the management of brain tumours in children. MATERIALS AND METHODS: A retrospective analysis was conducted of all stereotactic procedures performed in a single centre between 1996 and 2001. The success rates of achieving histologic diagnosis and a correlation between radiologic and histologic diagnosis were examined. RESULTS: There were 7 boys and 7 girls with a mean age of 9.1 years (range: 4-15). Under general anaesthetic 15 procedures were performed in 14 patients: 12 diagnostic and 3 therapeutic; 10 with CT and 5 with MRI guidance; 10 lesions were supratentorial and 4 were in the pons. A definitive histologic diagnosis was established in 10 of the 12 cases (diagnostic yield 83%). The pre-operative radiological diagnosis was accurate for tumour type in only 75% of the cases. In 3 patients cyst aspiration was attempted: post-operatively the cyst size was decreased in 2 and unchanged in 1. Seizures and acute confusion following biopsy of a thalamic tumour occurred in 1 patient. Post-operative scans were performed in 7 patients and in 2 we noted small, clinically insignificant, haemorrhages at the biopsy site. There was no mortality and morbidity was 6.6%. CONCLUSIONS: This small series confirms that stereotactic procedures in children are safe, well tolerated, with a high diagnostic yield, which could be improved with the use of intraoperative histopathological examination.

Glioma after cerebral hydatid disease.

BACKGROUND: The authors present the case of a 31-year-old man with a malignant glioma. He had been treated for cerebral hydatid as a child, and 22 years later he developed a glioma at the site of his previous disease. DISCUSSION: Could chronic inflammatory change following intracranial hydatid disease have induced neoplastic transformation of glial cells?

Stereotactic radiosurgery. XVII: Recurrent intrasellar craniopharyngioma.

Stereotactic radiosurgery for craniopharyngioma is usually a high risk procedure due to the intimate relationship of the tumour to the optic chiasm and conservative dosing has been advocated to reduce complication rates. In 2002, in a publication from Karolinska Hospital, Sweden, 13 out of 21 patients received only a marginal dose of 6 Gy (not considered a radical dose) and 11 out of 13 tumours progressed. This recent report must argue against single dose stereotactic radiosurgery as the primary radiation therapy modality in most cases. However, where the disease is 'away' from the optic apparatus, such constraints do not apply. We here report the successful treatment of three consecutive patients whose craniopharyngioma was confined to the pituitary fossa, and a finite distance from the optic pathways and in whom optimal dosing was employed.

Stereotactic radiosurgery XIV: The role of the haemosiderin 'ring' in the development of adverse reactions following radiosurgery for intracranial cavernous malformations: a sustainable hypothesis.

There are strong data supporting the clinical efficacy of ionizing radiation therapy in the treatment of extracranial cavernous angiomas; no unusual complications occur. There is no a priori reason to anticipate a high rate of complications following radiosurgery for brain cavernous angiomas and yet equivalent dose prescriptions (site, size and target volume) to those used for AVM are associated with a considerably higher complication rate. The observed sub-acute reactions sometimes recover with steroid therapy. Previous authors have not sought to define the aetiological basis of this observation. Haemosiderin staining of the fringe of normal brain tissue surrounding the cavernoma is a unique feature of these brain lesions and the potential radiosensitizing properties of this iron based substance, for which there is a considerable experimental and clinical observational basis for radiosensitization, are reviewed. These provide good support for the concept that this characteristic feature of brain cavernomas accounts for the higher post radiation reaction/complication rate. Treatment considerations, stemming from these observations, are suggested.

Can magnetic resonance imaging alone accurately define the arteriovenous nidus for gamma knife radiosurgery?

OBJECT: Current radiosurgical treatment of arteriovenous malformations (AVMs) relies on planning protocols that integrate data from both magnetic resonance (MR) imaging and stereotactic angiography studies. Angiography, however, is invasive and associated with a small but well-defined risk of neurological and systemic complications. Magnetic resonance imaging, on the other hand, is noninvasive with multiplanar capability, demonstrates good anatomical detail, and has been shown to be superior to angiography in the delineation of selected AVMs. METHODS: In this study, MR imaging-related accuracy of defining the AVM nidus in gamma knife radiosurgery is investigated using only T1- and T2-weighted sequences. CONCLUSIONS: Little interobserver variability was observed and AVM nidi, as demonstrated on T1- and T2-weighted MR images, were well correlated in terms of size. The displacement of the new target, however, from the original nidus, was not predictable and occasionally was significant, thus precluding safe radiosurgical planning.

Acute symptoms after gamma knife radiosurgery.

OBJECT: The purpose of this study was to examine the widely held assumption that early-onset symptoms after gamma knife radiosurgery (GKS) are uncommon. The study was designed to include all types of morbidity and not just those that lead to neurological dysfunction. It was hoped that the results of the study could lead to a more rational follow-up protocol. METHODS: Data regarding adverse events were collected prospectively (within 2-3 weeks post-GKS) by telephone interview from 47 of the first 65 patients who could be reached. Immediate adverse events were defined as any new or unexpected symptom developing within 2 weeks of treatment and were graded as mild, moderate, or severe. Two thirds of all patients complained of new adverse symptoms; three patients required prolonged hospitalization, although in one case this was not related to the radiosurgery. The majority of symptomatic patients (91%) experienced mild or moderate complications. More than 50% of patients had headache. One third described pin site-related complications and one fifth suffered from nausea/vomiting or marked tiredness. Patients with moderate symptoms had a larger mean tumor volume and higher radiation dose than other patient groups. Prior radiation therapy, lesion type, or the posttreatment administration of steroid agents did not significantly influence the development of acute symptoms. CONCLUSIONS: Acute adverse events following GKS are not uncommon if all types of morbidity are considered. An increased appreciation of these other complications may improve posttreatment care.

Is distortion correction necessary for digital subtraction angiography in the Gamma Knife treatment of intra-cranial arteriovenous malformations?

OBJECTIVE: The published literature maintains that distortion correction of digital subtraction angiography is essential for accurate definition of the arteriovenous malformation (AVM) nidus when performing Gamma Knife radiosurgery. However, as Gamma Knife treatments usually involve small volume targets, which are purposely positioned as close to the centre of the frame as possible, we postulated that the angiographic target images should be minimally distorted. Thus, the use of uncorrected images would not significantly compromise the accuracy of the treatment. We investigated this postulate. DESIGN: Patient and phantom images with and without distortion correction were assessed. The errors measured in the angiograms were compared to those of MR and CT images of the same subjects. Any errors less than 0.5 mm in any modality were accepted as intrinsic. RESULTS: All errors measured in the study were sub-millimetre. In the patient group, errors with distortion correction averaged 0.13 mm (range 0-0.3 mm). Without distortion correction, errors averaged 0.34 mm (range 0.1-0.6 mm). By comparison, the average error for intracranial MR imaging was 0.3 mm, with a maximum of 0.6 mm. CONCLUSION: For small, intracranial AVMs distortion correction did not significantly reduce the errors associated with the definition of the stereotactic co-ordinates. We suggest that prior to the purchase of this software, similar in-house testing should be performed.