The pseudotumor cerebri syndrome (PTCS) may be primary (idiopathic intracranial hypertension) or arise from an identifiable secondary cause. Characterization of typical neuroimaging abnormalities, clarification of normal opening pressure in children, and features distinguishing the syndrome of intracranial hypertension without papilledema from intracranial hypertension with papilledema have furthered our understanding of this disorder. We propose updated diagnostic criteria for PTCS to incorporate advances and insights into the disorder realized over the past 10 years.

The aim was to capture interdisciplinary expertise from a large group of clinicians, reflecting practice from across the UK and further, to inform subsequent development of a national consensus guidance for optimal management of idiopathic intracranial hypertension (IIH).MethodsBetween September 2015 and October 2017, a specialist interest group including neurology, neurosurgery, neuroradiology, ophthalmology, nursing, primary care doctors and patient representatives met. An initial UK survey of attitudes and practice in IIH was sent to a wide group of physicians and surgeons who investigate and manage IIH regularly. A comprehensive systematic literature review was performed to assemble the foundations of the statements. An international panel along with four national professional bodies, namely the Association of British Neurologists, British Association for the Study of Headache, the Society of British Neurological Surgeons and the Royal College of Ophthalmologists critically reviewed the statements.ResultsOver 20 questions were constructed: one based on the diagnostic principles for optimal investigation of papilloedema and 21 for the management of IIH. Three main principles were identified: (1) to treat the underlying disease; (2) to protect the vision; and (3) to minimise the headache morbidity. Statements presented provide insight to uncertainties in IIH where research opportunities exist.ConclusionsIn collaboration with many different specialists, professions and patient representatives, we have developed guidance statements for the investigation and management of adult IIH.

The perception of migraine headache, which is mediated by nociceptive signals transmitted from the cranial dura mater to the brain, is uniquely exacerbated by exposure to light. Here we show that exacerbation of migraine headache by light is prevalent among blind persons who maintain non-image-forming photoregulation in the face of massive rod/cone degeneration. Using single-unit recording and neural tract-tracing in the rat, we identified dura-sensitive neurons in the posterior thalamus, whose activity was distinctly modulated by light, and whose axons projected extensively across layers I through V of somatosensory, visual and associative cortices. The cell bodies and dendrites of such dura/light-sensitive neurons were apposed by axons originating from retinal ganglion cells, predominantly from intrinsically-photosensitive retinal ganglion cells – the principle conduit of non-image-forming photoregulation. We propose that photoregulation of migraine headache is exerted by a non-image-forming retinal pathway that modulates the activity of dura-sensitive thalamocortical neurons.

Patients with 'visual snow' report continuous tiny dots in the entire visual field similar to the noise of an analogue television. As they frequently have migraine as a comorbidity with ophthalmological, neurological and radiological studies being normal, they are offered various diagnoses, including persistent migraine aura, post-hallucinogen flashback, or psychogenic disorder. Our aim was to study patients with 'visual snow' to characterize the phenotype. A three-step approach was followed: (i) a chart review of patients referred to us identified 22 patients with 'visual snow'. Fifteen had additional visual symptoms, and 20 patients had comorbid migraine, five with aura; (ii) to identify systematically additional visual symptoms, an internet survey (n = 275) of self-assessed 'visual snow' subjects done by Eye On Vision Foundation was analysed. In two random samples from 235 complete data sets, the same eight additional visual symptoms were present in >33% of patients: palinopsia (trailing and afterimages), entoptic phenomena (floaters, blue field entoptic phenomenon, spontaneous photopsia, self-light of the eye), photophobia, and nyctalopia (impaired night vision); and (iii) a prospective semi-structured telephone interview in a further 142 patients identified 78 (41 female) with confirmed 'visual snow' and normal ophthalmological exams. Of these, 72 had at least three of the additional visual symptoms from step (ii). One-quarter of patients had 'visual snow' as long as they could remember, whereas for the others the mean age of onset was 21 ± 9 years. Thirty-two patients had constant visual symptoms, whereas the remainder experienced either progressive or stepwise worsening. Headache was the most frequent symptom associated with the beginning or a worsening of the visual disturbance (36%), whereas migraine aura (seven patients) and consumption of illicit drugs (five, no hallucinogens) were rare. Migraine (59%), migraine with aura (27%), anxiety and depression were common comorbidities over time. Eight patients had first degree relatives with visual snow. Clinical investigations were not contributory. Only a few treatment trials have been successful in individual patients. Our data suggest that 'visual snow' is a unique visual disturbance clinically distinct from migraine aura that can be disabling for patients. Migraine is a common concomitant although standard migraine treatments are often unhelpful. 'Visual snow' should be considered a distinct disorder and systematic studies of its clinical features, biology and treatment responses need to be commenced to begin to understand what has been an almost completely ignored problem.

Photophobia is a common yet debilitating symptom seen in many ophthalmic and neurologic disorders. Despite its prevalence, it is poorly understood and difficult to treat. However, the past few years have seen significant advances in our understanding of this symptom. We review the clinical characteristics and disorders associated with photophobia, discuss the anatomy and physiology of this phenomenon, and conclude with a practical approach to diagnosis and treatment.

The ODDS Consortium recommendations are important in the process of establishing a reliable and consistent diagnosis of ODD using OCT for both clinicians and researchers.

Objective To compare clinical features, visual characteristics, and treatment of idiopathic intracranial hypertension patients with and without papilledema. Background Idiopathic intracranial hypertension does not often occur without papilledema. This study estimates the prevalence and compares the clinical characteristics of idiopathic intracranial hypertension patients with and without papilledema. Methods We performed a cross-sectional analysis of all idiopathic intracranial hypertension patients diagnosed at the University of Utah Neuro-Ophthalmology Unit between 1990 and 2003. Patient records were reviewed for presence of papilledema and other signs, symptoms, and treatment characteristics. Each patient without papilledema was matched to the patient with papilledema who was closest to his/her age and sex. McNemar’s and Wilcoxon-signed rank sum tests were used to compare characteristics between matched pairs. Results Among all patients (n = 353), the prevalence of those without papilledema was 5.7% (n = 20). Patients without papilledema reported photopsias (20%), and were found to have spontaneous venous pulsations (75%) and non-physiologic visual field constriction (20%) more often than did those with papilledema. Mean opening pressure, although above normal, was lower in patients without papilledema (mean = 309 mm cerebrospinal fluid) compared with those with papilledema (mean = 373 mm cerebrospinal fluid, P = .031). Idiopathic intracranial hypertension patients without papilledema had more frequent diagnostic lumbar punctures than did patients with papilledema. Visual acuities and treatment were similar between groups. Conclusions The clinical presentation of idiopathic intracranial hypertension without papilledema is only somewhat different from that of idiopathic intracranial hypertension with papilledema. The lower opening pressure in patients without papilledema may explain variations in symptoms and signs between the 2 groups. When there are visual field changes in idiopathic intracranial hypertension without papilledema, non-physiologic visual loss should be considered.

Pseudotumor cerebri (PTC) is most commonly seen in obese women of reproductive age. We studied 109 women with PTC between ages 16 and 44 years. In 11, PTC started during pregnancy. Thirteen women with previous diagnosis of PTC, including two of the aforementioned 11, had an additional 17 documented pregnancies. Patients were matched by age and parity with controls. Obstetric complications occurred more frequently in the controls. Visual loss occurred with the same frequency in pregnant and nonpregnant patients. Treatment of PTC patients in pregnancy should be the same as for nonpregnant PTC patients, except that calorie restriction and diuretic use are contraindicated. Obstetric management is no different from that of normal pregnancy.