Alexandra K. Ball

Low energy diet and intracranial pressure in women with idiopathic intracranial hypertension: prospective cohort study

Objective To observe intracranial pressure in women with idiopathic intracranial hypertension who follow a low energy diet. Design Prospective cohort study. Setting Outpatient department and the clinical research facility based at two separate hospitals within the United Kingdom. Participants 25 women with body mass index (BMI) >25, with active (papilloedema and intracranial pressure >25 cm H2O), chronic (over three months) idiopathic intracranial hypertension. Women who had undergone surgery to treat idiopathic intracranial hypertension were excluded. Intervention Stage 1: no new intervention; stage 2: nutritionally complete low energy (calorie) diet (1777 kJ/day (425 kcal/day)); stage 3: follow-up period after the diet. Each stage lasted three months. Main outcome measure The primary outcome was reduction in intracranial pressure after the diet. Secondary measures included score on headache impact test-6, papilloedema (as measured by ultrasonography of the elevation of the optic disc and diameter of the nerve sheath, together with thickness of the peripapillary retina measured by optical coherence tomography), mean deviation of Humphrey visual field, LogMAR visual acuity, and symptoms. Outcome measures were assessed at baseline and three, six, and nine months. Lumbar puncture, to quantify intracranial pressure, was measured at baseline and three and six months. Results All variables remained stable over stage 1. During stage 2, there were significant reductions in weight (mean 15.7 (SD 8.0) kg, P<0.001), intracranial pressure (mean 8.0 (SD 4.2) cm H2O, P<0.001), score on headache impact test (7.6 (SD 10.1), P=0.004), and papilloedema (optic disc elevation (mean 0.15 (SD 0.23) mm, P=0.002), diameter of the nerve sheath (mean 0.7 (SD 0.8) mm, P=0.004), and thickness of the peripapillary retina (mean 25.7 (SD 36.1) µ, P=0.001)). Mean deviation of the Humphrey visual field remained stable, and in only five patients, the LogMAR visual acuity improved by one line. Fewer women reported symptoms including tinnitus, diplopia, and obscurations (10 v 4, P=0.004; 7 v 0, P=0.008; and 4 v 0, P=0.025, respectively). Re-evaluation at three months after the diet showed no significant change in weight (0.21 (SD 6.8) kg), and all outcome measures were maintained. Conclusion Women with idiopathic intracranial hypertension who followed a low energy diet for three months had significantly reduced intracranial pressure compared with pressure measured in the three months before the diet, as well as improved symptoms and reduced papilloedema. These reductions persisted for three months after they stopped the diet.

NMR‐based metabolomic analysis of cerebrospinal fluid and serum in neurological diseases – a diagnostic tool?

We sought to evaluate the diagnostic accuracy of metabolomic biomarker profiles in neurological conditions (idiopathic intracranial hypertension (IIH), multiple sclerosis (MS) and cerebrovascular disease (CVD) compared to controls with either no neurological disease or mixed neurological diseases).

The prevalence of vitamin D abnormalities in South Asians with type 2 diabetes mellitus in the UK

Background:  The high prevalence of both hypovitaminosis D and type 2 diabetes (T2DM) in the Asian community is well recognised, but the impact of diabetes on vitamin D status and vice versa, has not been well reported.

Exploring the pathogenesis of IIH: An inflammatory perspective

Idiopathic intracranial hypertension (IIH) is a common blinding condition amongst the young obese female population (20 per 100,000) characterised by elevated intracranial pressure (ICP). The aetiology of IIH is not known. In this review we explore the literature investigating the pathogenesis of IIH and suggest additional hypotheses. Chronic inflammation is emerging as an aetiological factor in the pathogenesis of obesity and we propose that this may be a feature of IIH. Obesity is also related to dysregulation of cortisol production by the pre-receptor enzyme, 11beta-hydroxysteroid dehydrogenase, and we speculate that this may have a role in the pathogenesis of obesity and raised ICP seen in IIH.

Elevated cerebrospinal fluid (CSF) leptin in idiopathic intracranial hypertension (IIH): evidence for hypothalamic leptin resistance?

Objective  The aetiology of idiopathic intracranial hypertension (IIH) is not known, but its association with obesity is well‐recognized. Recent studies have linked obesity with abnormalities in circulating inflammatory and adiposity related cytokines. The aim of this study was to characterize adipokine and inflammatory cytokine profiles in IIH.

Idiopathic Intracranial Hypertension Associated with Iron Deficiency Anaemia: A Lesson for Management

Aim: To document the causal association of iron deficiency anaemia (IDA) and intracranial hypertension (IH). Methods: A consecutive case note review of patients with a clinical diagnosis of idiopathic intracranial hypertension (IIH) and anaemia presenting to a tertiary referral unit over a 2.5-year period. Demographics, aetiology and clinical details were recorded and analysed. Results: Eight cases were identified from 77 new cases presenting with IIH. All 8 had documented microcytic anaemia with clinical evidence of raised intracranial pressure. There was no evidence of venous sinus thrombosis on MRI and MR venography in 7 subjects and on repeated CT venography in 1. On correction of anaemia alone, 7 cases resolved. One patient with severe progressive visual loss underwent ventriculoperitoneal shunt in addition to treatment of anaemia, with good outcome. The incidence of this association is 10.3%. Conclusion: These cases present an association between IDA and IH, in the absence of cerebral sinus thrombosis. As a clinically significant proportion of cases presenting with signs of IIH have IDA, we recommend all patients presenting with IIH have full blood counts and if they are found to be anaemic, they should be treated appropriately.

074 Rating papilloedema: an evaluation of the Frisen classification in idiopathic intracranial hypertension

Optic disc appearance is a key measure of disease status in Idiopathic Intracranial Hypertension (IIH). Frisen classification describes stages of papilloedema (grades 0–5) and is used internationally, in clinical and research practice. No studies have evaluated Frisen classification since its original description. We assess the inter-rater reproducibility and sensitivity of Frisen classification, compared with our system of ranking papilloedema severity, in IIH. Six masked neuro-ophthalmologists reviewed paired disc photographs (before and after treatment) from 47 patients with IIH (25 acute and 22 chronic) and assigned a Frisen grade. Additionally paired discs were ranked in order of papilloedema severity, (disc ranking). 188 discs were reviewed. Agreement among all reviewers was noted in only three instances (1.6%) when using Frisen classification, compared with 40 instances of exact agreement (44.6%) for disc ranking. The probability of agreement between any two reviewers was 36.1% for Frisen grade and 70.0% for disc ranking. Disc ranking had significantly greater sensitivity, identifying a difference in 75.3% of paired photographs compared to 53.2% for Frisen grade (p<0.001). We demonstrate the limited sensitivity and reproducibility of Frisen classification in IIH. Simple optic disc ranking was more sensitive and reproducible. The use of disc ranking in clinical practice and research studies is recommended until alternative schemes, specific to IIH, have been developed.