A recent surge of nitrous oxide misuse around London which merits a public health warning.

Background: Use of nitrous oxide (N2O) gas for recreational purposes by young people is increasingly recognized as a public health hazard in the UK.

Methods: We looked at the hospital records of patients admitted over the last 4 years to a single neurological centre in Essex to determine the demographics, presentation, and management of patients presenting with symptoms of N2O toxicity from its recreational use.

Results: Of the 17 patients (mean age = 22.

Potential Surgical Implications of Internal Jugular Stenosis in a Craniocervical Junction Meningioma.

We report a case of a 61-year-old lady presenting with several weeks of progressive left-sided weakness, and found to have a foramen magnum meningioma. She was counselled on surgical resection of the tumour, and a preoperative computed tomography angiogram (CTA) was obtained for operative planning purposes. CTA demonstrated incidental bilateral internal jugular vein (IJV) stenosis, with enlarged extracranial collateral vessels and elongated styloid processes.

Validation of an artificial intelligence solution for acute triage and rule-out normal of non-contrast CT head scans.

Purpose: Non-contrast CT head scans provide rapid and accurate diagnosis of acute head injury; however, increased utilisation of CT head scans makes it difficult to prioritise acutely unwell patients and places pressure on busy emergency departments (EDs). This study validates an AI algorithm to triage patients presenting with Intracranial Haemorrhage (ICH) or Acute Infarct whilst also identifying a subset of patients as Normal, with the potential to function as a rule-out test.

Methods: In total, 390 CT head scans were collected from 3 institutions in the UK, US and India.

Respiratory difficulty with palatal, laryngeal and respiratory muscle tremor in adult-onset Alexander's disease.

Sleep apnoea and respiratory difficulties are reported in adult-onset Alexander's disease (AOAD), an autosomal-dominant leukodystrophy that presents mainly with progressive ataxia. We demonstrate for the first time that the respiratory symptoms can result from association of palatal tremor with a similar tremor of laryngeal and respiratory muscles that interrupts normal inspiration and expiration.A 60-year-old woman presented with progressive ataxia, palatal tremor and breathlessness.

Anti-collapsin response mediator protein 5 encephalitis masquerading as a low-grade brain tumour.

A 71-year-old woman presented acutely with seizures; her MRI suggested a low-grade glioma of the right temporal lobe. Over the preceding 18 months, she had developed progressive limb chorea and orofacial dyskinesia. Examination showed a predominantly amnestic cognitive profile.

A rare stapes abnormality.

The aim of this study is to increase awareness of rare presentations, diagnostic difficulties alongside management of conductive hearing loss and ossicular abnormalities. We report the case of a 13-year-old female reporting progressive left-sided hearing loss and high resolution computed tomography was initially reported as normal. Exploratory tympanotomy revealed an absent stapedius tendon and lack of connection between the stapes superstructure and footplate.

Reversible cerebral vasoconstriction syndrome as a cause of thunderclap headache: a retrospective case series study.

Thunderclap headache is a common emergency department presentation. Although subarachnoid hemorrhage (SAH) should be the first diagnosis to exclude, reversible cerebral vasoconstriction syndrome (RCVS) is an important alternative cause, which may be commoner than appreciated. Reversible cerebral vasoconstriction syndrome is characterized by multifocal narrowing of cerebral arteries, typically manifested by acute, severe headache with or without neurologic deficits.

Wholly endoscopic permeatal removal of a petrous apex cholesteatoma.

We report a case of a petrous apex cholesteatoma which was managed with a wholly endoscopic permeatal approach. A 63-year-old Caucasian male presented with a 10-year history of right-sided facial palsy and profound deafness. On examination in our clinic, the patient had a grade VI House-Brackmann paresis, otoscopic evidence of attic cholesteatoma behind an intact drum, and extensive scarring of the face from previous facial reanimation surgery.

Do immediate cytology and specialist radiologists improve the adequacy of ultrasound-guided fine-needle aspiration cytology?

Objective: To assess whether a dedicated "1-stop" neck lump clinic has improved the percentage of adequate fine-needle aspiration cytology (FNAC) samples and reduced the need for repeat FNAC.

Study Design: Retrospective review.

Setting: District General Hospital in the United Kingdom.

Peripartum isolated cortical vein thrombosis in a mother with postdural puncture headache treated with an epidural blood patch.

A 32-year-old woman presented with low pressure headache 3 days after delivery of her baby. An assessment of postdural puncture headache was made. This was initially treated with analgesia, caffeine, and fluids for the presumed cerebrospinal fluid (CSF) leak.

Paravertebral cervical chordoma--a case report.

Chordomas constitute <5% of vertebral column tumours and a third of these arise in the upper cervical spine and tend to be clival - usually midline, with occasional eccentric extension. We report a case of cervical chordoma presenting as a lateral neck mass and discuss its origin, diagnosis and management.

Delayed fibrotic obliteration of the spinal subarachnoid space after cerebral aneurysmal subarachnoid hemorrhage: case report.

Objective: Widespread fibrotic obliteration of the spinal subarachnoid space after cerebral aneurysmal subarachnoid hemorrhage (SAH) is rare.

Clinical Presentation: A 57-year-old woman presented with the gradual development of a spastic paraparesis. Two years earlier, she experienced a cerebral aneurysmal SAH that was successfully managed with endovascular coiling.

The implications of ISAT and ISUIA for the management of cerebral aneurysms during pregnancy.

Both the International Subarachnoid Aneurysm Trial (ISAT) and the International Study on Unruptured Intracranial Aneurysms (ISUIA) have been widely extrapolated to influence the management of actual or anticipated aneurysmal subarachnoid hemorrhage (SAH). However, it remains possible that sub-groups exist for which such extrapolation might subsequently prove premature. In this review, we discuss the implications that such extrapolation may potentially have for one such SAH sub-group: the clinically rare scenario of SAH in pregnancy.

Lumbar extradural arteriovenous malformation: case report and literature review.

Background Context: Most spinal arteriovenous malformations (AVMs) are dural arteriovenous fistulas in which a singularly intradural venous drainage emanates from an extradural nidus. A pure extradural spinal arteriovenous malformation (E-AVM), in the absence of a vertebral body (cavernous) hemangioma, is extremely rare, and full clinical, radiological, and operative descriptions are scant.

Purpose: To fully document the rare occurrence of a symptomatic E-AVM producing spinal claudication.

"Disc cysts" and "posterior longitudinal ligament ganglion cysts": synonymous entities? Report of three cases and literature review.

Objective And Importance: Extradural cysts intimately associated with relatively normal lumbar discs have rarely been reported. Histologically nonspecific, most have been designated posterior longitudinal ligament (PLL) or annulus fibrosus (AF) "ganglion cysts." Recently, "disc cysts" have been distinguished as a separate entity, mostly on the grounds of cyst-disc communication.

Intracranial aneurysms treated with endovascular coils: detection of recurrences using unenhanced and contrast-enhanced transcranial color-coded duplex sonography.

Background And Purpose: Because neck recurrence after endovascular treatment of intracranial aneurysms (IAs) is not uncommon, surveillance to assess long-term stability of occlusion is clearly important. This study evaluated unenhanced and contrast-enhanced transcranial color-coded duplex sonography (TCCS) in detecting refilling of IAs treated with detachable coils.

Methods: Patients with coiled IAs were imaged before and after contrast enhancement.

Acute obstructive hydrocephalus associated with infratentorial subdural hygromas complicating Chiari malformation Type I decompression. Report of two cases and literature review.

Obstructive hydrocephalus complicating foramen magnum decompression (FMD) for a Chiari malformation (CM) Type I is rare. Two female patients (17 and 55 years old) presented with strain-related headaches. In both cases magnetic resonance (MR) imaging studies confirmed a CM Type I, which was accompanied by syringomyelia in one case.

Primary extradural epithelioid leiomyosarcoma of the cervical spine: case report and literature review.

Objective And Importance: No case of primary epithelioid leiomyosarcoma involving the spine has been reported previously.

Clinical Presentation: A 61-year-old Nigerian woman presented with progressive spastic quadriparesis and acute urinary retention. Her only medical history included a total abdominal hysterectomy for fibroids 10 years earlier in Nigeria.

Change in CT radiodensity of a colloid cyst of the third ventricle: case report and literature review.

A unique case is presented of a decrease in density on CT scans of a colloid cyst of the third ventricle with time. This occurred in the absence of any operative intervention in a 35-year-old woman.

Aneurysmal subarachnoid haemorrhage in pregnancy.

Although uncommon, aneurysmal subarachnoid haemorrhage (SAH) in pregnancy can be devastating for both mother and baby. It is the leading cause of other indirect maternal death in England and Wales accounting for 60 deaths in the decade 1988-1999. No single obstetric or neurosurgical unit has sufficiently large database or experience in managing this condition in pregnancy.