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 H 2 O), chronic (over three months) idiopathic intracranial hypertension. Women who had undergone surgery to treat idiopathic intracranial hypertension were excluded.

SUMMARYWolfram syndrome is the association of diabetes mellitus and optic atrophy, also called DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy and deafness). Incomplete characterisation has caused diagnostic confusion; we therefore undertook a nation wide cross-sectional case finding study. We identified 45 patients with Wolfram syndrome, median age 29 years.All patients fulfilled the ascertainment criteria (juvenile onset diabetes mellitus and optic atrophy). Optic atrophy presented in 38 patients with rednced visual acuity and colour vision defect (median age 11 years), progressing to visual acuity of 6/60 or less in 35 patients (median time 8 years, range 1-25 years). Visual field examinations recorded before acuity deteriorated showed central scotomas with peripheral constriction.Blind patients had absent pupillary reftexes. Horizontal nystagmus was seen in patients with other signs of cerebellar degeneration. There was no pigmentary retinal dystrophy; only 3 patients had background diabetic retinopathy, despite a median duration of diabetes of 24 years. Electroretinography was normal in 3 patients and showed reduced amplitude in 3 patients; visual evoked responses were abnormal (10/10 patients: reduced amplitude to both ftash and pattern stimula tion). Magnetic resonance imaging showed generalised brain atrophy with reduced signal from the optic nerves and chiasm. A postmortem brain specimen from one patient revealed atrophy of the optic nerves, chiasm, cerebellum and brainstem. We found no evidence of mitochondrial genome defects or rearrangements. This primary neurogenerative disorder presents with dia betes mellitus and progressive optic atrophy, probably due to pathology in the optic nerve.

Supplemental O2 reduces cardiac output and raises systemic vascular resistance in congestive heart failure. In this study, 100% O2 was given to normal subjects and peak forearm flow was measured. In experiment 1, 100% O2 reduced blood flow and increased resistance after 10 min of forearm ischemia (flow 56.7 +/- 7.9 vs. 47.8 +/- 6.7 ml.min-1.100 ml-1; P < 0.02; vascular resistance 1.7 +/- 0.2 vs. 2.4 +/- 0.4 mmHg.min.100 ml.ml-1; P < 0.03). In experiment 2, lower body negative pressure (LBNP; -30 mmHg) and venous congestion (VC) simulated the high sympathetic tone and edema of congestive heart failure. Postischemic forearm flow and resistance were measured under four conditions: room air breathing (RA); LBNP+RA; RA+LBNP+VC; and 100% O2+LBNP+VC. LBNP and VC did not lower peak flow. However, O2 raised minimal resistance (2.3 +/- 0.4 RA; 2.8 +/- 0.5 O2+LBNP+VC, P < 0.04). When O2 alone (experiment 1) was compared with O2+LBNP+VC (experiment 2), no effect of LBNP+VC on peak flow or minimum resistance was noted, although the return rate of flow and resistance toward baseline was increased. O2 reduces peak forearm flow even in the presence of LBNP and VC.

This study initiated by a self-help migraine group investigated disability caused by visual environmental stimuli, e.g. glare, flicker, pattern and color. One thousand forty-four women with migraine completed the self-report questionnaire on visual environmental stimuli reported in earlier studies to precipitate or aggravate migraine. One hundred twenty-one female controls were obtained from general practice and hospital out-patients. The responses of the classical, common and non-migraine groups were compared. Women with classical migraine expressed greater disability than those with common migraine or controls both in respect of number of visual sensitivities reported (P < 0.0001) and severity of consequences of such stimuli (P < 0.0001). This study indicated differences between classical and common migraine outside of the attack phase apart from aura. Reported range of sensitivities for the migraineurs peaked between the ages of 46-60 years. A high level of unrealized disability caused by visual environmental stimuli was thus identified in hitherto unexplored self-help groups.

The incidence of the life time history of both maternal migraine and depression were assessed in children with headache, migraine, recurrent abdominal pain and abdominal migraine. An epidemiological survey of 1,104 children registered with a general practice was undertaken. The incidence of maternal migraine and depression agreed with previous estimates. Children with migraine had a greater proportion of mothers with a history of migraine than those who experienced headache alone compared with controls. The survey showed that mothers with depression predisposed their children to headache but not specifically migraine. A history of maternal depression and migraine was significantly more common and proportionately higher in children with abdominal migraine and recurrent abdominal pain.

20 children with clinically diagnosed migraine were asked to wear either a rose coloured tint or density matched blue tint for a period of 4 months. The frequency, duration and intensity of migraine attacks were recorded, together with the amount of visually provoked beta activity in the EEG. After one month's wear all the children in the study revealed an initial improvement in headache frequency. However, only those children wearing rose tints sustained this improvement up to 4 months, when the mean headache frequency had improved from 6.2 per month to 1.6 per month. The headache frequency of those children wearing blue tints revealed no overall improvement after 4 months. The improvements in headache frequency in children wearing rose tints correlated with a reduction in visually provoked beta activity.

This is the only murine model of closed globe injury and the only model of retinal trauma with specific photoreceptor cell death. The clinical appearance mirrors that in severe retinal injury after blunt ocular trauma in humans, and the ultrastructural features are consistent with human and animal studies of commotio retinae. After ocular trauma, photoreceptor apoptosis may be prevented and visual outcomes improved by blocking of the cell death pathways.

Mutations in CNGB3, which have been shown to cause achromatopsia, are now shown to be associated with autosomal recessive progressive cone dystrophy. In this study, a novel Arg403Gln mutation was identified, located in the middle of the pore domain of the cone CNG cation channel beta-subunit, which when associated with the nonsense mutation Thr383fs, resulted in progressive cone dystrophy.