Differing presenting features of idiopathic intracranial hypertension in the UK and US.

AIM: Demographic factors potentially influencing the presentation and severity of idiopathic intracranial hypertension (IIH) in the US vs. UK populations include obesity and ethnicity. We aimed to compare the presenting features of IIH between populations in the UK and US tertiary referral centres, to assess what population differences exist and whether these cause different presentations and impact on visual function. METHODS: Clinical data were collected on 243 consecutive UK IIH patients and 469 consecutive US IIH patients seen after 2012 in two tertiary centres. Visual function was defined as severe visual loss when Humphrey visual field mean deviation was <-15 dB, when Goldmann visual fields showed constriction or when visual acuity was <20/200. RESULTS: US patients were more commonly of self-reported black race (58.9% vs. 7.1%) than UK patients, but had a similar mean body mass index (38.3 ± 0.63kg/m2 UK vs. 37.7 ± 0.42kg/m2 US; p = 0.626). The UK cohort had lower presenting Frisén grade (median 1 vs. 2; p < 0.001) and severe visual loss less frequently (15.4% vs. 5%; p = 0.014), but there was no difference in mean cerebrospinal fluid-opening pressure (CSF-OP) (35.8 ± 0.88cmH2O UK vs. 36.3 ± 0.52cmH2O US; p = 0.582). African Americans had poorer visual outcomes compared with US whites (19.4% vs. 10% severe visual loss; p = 0.011). Visual function was weakly associated with CSF-OP (R2 = 0.059; p = 0.001), which was similar between UK and US patients. CONCLUSIONS: The UK and the US cohorts had a similar average presenting BMI. However, the worse presenting visual function in the US IIH cohort was partially attributable to differences in the black populations in the two countries.

Noninvasive Assessment of Intracranial Pressure Status in Idiopathic Intracranial Hypertension Using Displacement Encoding with Stimulated Echoes (DENSE) MRI: A Prospective Patient Study with Contemporaneous CSF Pressure Correlation.

BACKGROUND AND PURPOSE: Intracranial pressure is estimated invasively by using lumbar puncture with CSF opening pressure measurement. This study evaluated displacement encoding with stimulated echoes (DENSE), an MR imaging technique highly sensitive to brain motion, as a noninvasive means of assessing intracranial pressure status. MATERIALS AND METHODS: Nine patients with suspected elevated intracranial pressure and 9 healthy control subjects were included in this prospective study. Controls underwent DENSE MR imaging through the midsagittal brain. Patients underwent DENSE MR imaging followed immediately by lumbar puncture with opening pressure measurement, CSF removal, closing pressure measurement, and immediate repeat DENSE MR imaging. Phase-reconstructed images were processed producing displacement maps, and pontine displacement was calculated. Patient data were analyzed to determine the effects of measured pressure on pontine displacement. Patient and control data were analyzed to assess the effects of clinical status (pre-lumbar puncture, post-lumbar puncture, or control) on pontine displacement. RESULTS: Patients demonstrated imaging findings suggesting chronically elevated intracranial pressure, whereas healthy control volunteers demonstrated no imaging abnormalities. All patients had elevated opening pressure (median, 36.0 cm water), decreased by the removal of CSF to a median closing pressure of 17.0 cm water. Patients pre-lumbar puncture had significantly smaller pontine displacement than they did post-lumbar puncture after CSF pressure reduction (P = .001) and compared with controls (P = .01). Post-lumbar puncture patients had statistically similar pontine displacements to controls. Measured CSF pressure in patients pre- and post-lumbar puncture correlated significantly with pontine displacement (r = 0.49; P = .04). CONCLUSIONS: This study establishes a relationship between pontine displacement from DENSE MR imaging and measured pressure obtained contemporaneously by lumbar puncture, providing a method to noninvasively assess intracranial pressure status in idiopathic intracranial hypertension.

Functional and simulated visual loss.

Nonorganic visual loss (NOVL) is the cause of a large number of referrals to neurologists and ophthalmologists and is a frequent area of overlap between neurologists, ophthalmologists, and psychiatrists. NOVL is the presence of visual impairment without an organic cause for disease despite a thorough and comprehensive investigation. A diagnosis of NOVL requires both the absence of any findings on examination and proof of the integrity and functioning of the visual system. Although sometimes a challenging diagnosis to make, there are a number of techniques and maneuvers which can be utilized fairly easily, either at the bedside or in the clinic, to help determine if a patient has NOVL. In some instances specialized testing, such as formal visual field testing, optical coherence tomography, visual evoked responses, electroretinogram, and various imaging modalities (magnetic resonance imaging) are performed to help determine if the cause of visual loss is organic or nonorganic. Once a diagnosis of NOVL is made, treatment centers around reassurance of the patient, close follow-up, and, if necessary, referral to a psychiatrist, as these patients may have underlying psychiatric disorders and a preceding strong emotional event leading to the current symptoms, and may be more likely to develop depression and anxiety.

Optical coherence tomography (OCT) in optic neuritis and multiple sclerosis.

Optical coherence tomography (OCT) is a non-invasive imaging technique routinely used in ophthalmology to visualize and quantify the layers of the retina. It also provides information on optic nerve head topography, peripapillary retinal nerve fiber layer thickness, and macular volume, which correlate with axonal loss. These measurements are of particular interest in optic neuropathies and in multiple sclerosis, and OCT parameters are now used as endpoints in neurologic clinical trials.

Atypical idiopathic intracranial hypertension: normal BMI and older patients.

BACKGROUND: Idiopathic intracranial hypertension (IIH) typically affects young, obese women. We examined 2 groups of atypical patients with IIH: those with a normal body mass index (BMI) and those at least 50 years of age. METHODS: A retrospective cohort study of 407 consecutive adult patients with IIH with known BMI from 3 centers was undertaken. Demographics, associated factors, visual acuity, and visual fields were collected at presentation and follow-up. RESULTS: We identified 18 IIH patients (4%) with normal BMI and 19 (5%) aged 50 years or older at the time of diagnosis who were compared with the remainder of the cohort. Medication-induced IIH was more frequent in patients with IIH with normal BMI (28 vs 7%, p = 0.008). No patient with IIH with a normal BMI had severe visual loss in either eye (0 vs 17%, p = 0.09). Older patients with IIH had a lower BMI, but were still generally obese (33 vs 38, p = 0.04). Older patients were less likely to report headache as initial symptom (37 vs 76%, p < 0.001) and more likely to complain of visual changes (42 vs 21%, p = 0.03). Treatment of any type was less likely in older patients (significant for medications: 74 vs 91%, p = 0.004), and they were more likely to have persistent disc edema at last follow-up (median Frisén grade: 1 vs 0, p = 0.002), but had similar, if not better, visual outcomes compared with younger patients. A case-control study did not identify any new medication or risk factor associations. CONCLUSIONS: Patients with normal body mass index and those 50 years or older make up a small proportion of patients with idiopathic intracranial hypertension (IIH), but appear to have better visual outcomes than more typical patients with IIH.

Pain in ischaemic ocular motor cranial nerve palsies.

AIM: Pain is a common feature of microvascular ischaemic ocular motor cranial nerve palsies (MP). The natural history of pain in this condition has not been studied. The purpose of this report is to define the spectrum of pain in isolated MP, with special reference to diabetic versus non-diabetic patients. DESIGN AND METHODS: Retrospective and prospective chart review was performed on 87 patients with acute-onset MP of a single cranial nerve (CN III, oculomotor; CN IV, trochlear; CN VI, abducens) that progressively improved or resolved over 6 months. RESULTS: Five of the 87 patients had two events, making the total number events 92. There were 39 (42.4%) CN III palsies, five (5.4%) CN IV palsies and 48 (52.2%) CN VI palsies. Thirty-six (41%) patients had diabetes. Pain was present in 57 (62%) events. The majority of diabetic and non-diabetic patients had pain. Pain preceded diplopia by 5.8 (SD 5.5) days in one-third of events. There was a trend towards greater pain with CN III palsies, but this was not statistically significant. Patients who experienced severe pain tended to have pain for a longer duration (26.4 (SD 21.7) days compared with 10.8 (SD 8.3) and 9.5 (SD 9) days for mild and moderate pain, respectively). There was no correlation between having diabetes and experiencing pain. CONCLUSIONS: The majority of MP are painful, regardless of the presence or absence of diabetes. Pain may occur prior to or concurrent with the onset of diplopia. Non-diabetic and diabetic patients presented with similar pain characteristics, contrary to the belief that diabetic patients have more pain associated with MP.

Idiopathic intracranial hypertension: a comparison between French and North-American white patients.

OBJECTIVE: To compare French and American white patients with idiopathic intracranial hypertension (IIH), and to determine prognostic factors associated with visual loss. METHODS: Medical records of all consecutive white patients with definite IIH seen between 2001 and 2006 in three French tertiary care medical centers and one American tertiary medical center were reviewed. Demographics, associated clinical features, and visual function at presentation and follow-up were collected. French white patients were compared to American white patients. RESULTS: One hundred and thirty-four patients (66 French, 68 American) were included. American patients were 8.7 times more likely than French patients to have visual acuity 20/60 or worse or visual field constriction (95% CI: 2.1-36.1, p=0.0001). American patients were treated more aggressively than French patients. French patients were older (31 vs. 28 years, p=0.02) and more likely to have anemia (20 vs. 2%, p<0.001). American patients had a longer duration of symptoms prior to diagnosis (12 vs. 4 weeks, p=0.01) and longer follow-up than French patients (26 vs. 11 months, p=0.001). Multivariable analysis found that nationality was an independent risk factor for visual loss. French and American patients did not differ regarding gender proportion, frequency of obesity, sleep apnea, endocrine diseases, or systemic hypertension. Cerebrospinal fluid (CSF) opening pressures were similar in both groups. CONCLUSION: American patients with IIH had worse visual outcomes than French patients despite more aggressive treatment. These differences are not explained by differences in previously known risk factors.

Idiopathic intracranial hypertension in men.

OBJECTIVE: To compare the characteristics of idiopathic intracranial hypertension (IIH) in men vs women in a multicenter study. METHODS: Medical records of all consecutive patients with definite IIH seen at three university hospitals were reviewed. Demographics, associated factors, and visual function at presentation and follow-up were collected. Patients were divided into two groups based on sex for statistical comparisons. RESULTS: We included 721 consecutive patients, including 66 men (9%) and 655 women (91%). Men were more likely to have sleep apnea (24% vs 4%, p < 0.001) and were older (37 vs 28 years, p = 0.02). As their first symptom of IIH, men were less likely to report headache (55% vs 75%, p < 0.001) but more likely to report visual disturbances (35% vs 20%, p = 0.005). Men continued to have less headache (79% vs 89%, p = 0.01) at initial neuro-ophthalmologic assessment. Visual acuity and visual fields at presentation and last follow-up were significantly worse among men. The relative risk of severe visual loss for men compared with women was 2.1 (95% CI 1.4-3.3, p = 0.002) for at least one eye and 2.1 (95% CI 1.1-3.7, p = 0.03) for both eyes. Logistic regression supported sex as an independent risk factor for severe visual loss. CONCLUSION: Men with idiopathic intracranial hypertension (IIH) are twice as likely as women to develop severe visual loss. Men and women have different symptom profiles, which could represent differences in symptom expression or symptom thresholds between the sexes. Men with IIH likely need to be followed more closely regarding visual function because they may not reliably experience or report other symptoms of increased intracranial pressure.

[Management of isolated optic neuritis in France: survey of neurologists and ophthalmologists]. / Prise en charge des névrites optiques isolées en France: enquête auprès des neurologues et des ophtalmologistes.

BACKGROUND: Acute isolated optic neuritis is often the first manifestation of multiple sclerosis (MS). Despite the results of several clinical trials its management remains controversial. With the advent of new disease-modifying agents for the treatment of MS, management of isolated optic neuritis has become more complicated. The goal of this study was to evaluate the current clinical practice of French ophthalmologists and neurologists in the management of acute isolated optic neuritis, and to evaluate the impact of recently published randomized clinical trials on their practice. METHODS: A survey, including 24 questions on the diagnosis and treatment of acute isolated optic neuritis was sent to all neurologists and to a sample of ophthalmologists in France. RESULTS: The responses of 655 neurologists and 141 ophthalmologists were analyzed. This study shows mostly that patients initially present more frequently to ophthalmologists, and are subsequently referred to neurologists. Most optic neuritis patients undergo a brain MRI and a lumbar puncture. Although most patients receive high dose intravenous steroids, up to 15% of neurologists and 21% of ophthalmologists still recommend oral prednisone (1 mg/kg per day). Steroids are often prescribed for the wrong reason, including to improve final visual acuity or decrease the risk of MS. Disease modifying agents are sometimes prescribed outside of the official French recommendations. CONCLUSION: The evidence-based guidelines are only partially followed by practitioners managing patients with acute optic neuritis.

Racial differences in idiopathic intracranial hypertension.

OBJECTIVE: To evaluate racial differences in idiopathic intracranial hypertension (IIH). METHODS: Medical records of all consecutive patients with definite IIH seen between 1989 and 2006 were reviewed. Demographics, associated factors, and visual function at presentation and follow-up were collected. Black patients were compared to non-black patients. RESULTS: We included 450 patients (197 black, 253 non-black). Obesity, systemic hypertension, anemia, and sleep apnea were more common in black patients than in non-black patients (p

The "sunglasses sign" predicts nonorganic visual loss in neuro-ophthalmologic practice.

OBJECTIVE: The aim of our study was to evaluate whether wearing sunglasses (the "sunglasses sign") can be used by neuro-ophthalmologists to predict nonorganic visual loss (NOVL) in their patients. METHODS: We prospectively collected information on all new patients seen by us over 13 months. We included all patients who ultimately received a diagnosis of NOVL, and all patients wearing sunglasses in our clinic. We recorded demographics, iris color, number of positive review of systems, ocular examination, precipitating event or trauma, workers' compensation claims, disability and lawsuit related to the visual loss, and the reason for wearing sunglasses. RESULTS: Among the 1,377 consecutive new patients seen in our clinic during the study, 34 patients wore sunglasses, among whom 7 (20.6%) had organic visual loss. During the study period, 59 patients were diagnosed with NOVL, among whom 27 (45.8%) wore sunglasses. The sensitivity of wearing sunglasses for NOVL was 0.46 (95% CI 0.33 to 0.59). The probability that a patient walking into our clinic had NOVL was 0.043 (95% CI 0.033 to 0.055); it increased to 0.79 (95% CI 0.62 to 0.91) in sunglasses patients. The specificity of sunglasses for the diagnosis of NOVL was 0.995 (95% CI 0.989 to 0.998). At least one of the following characteristics (highly positive review of systems, workers' compensation claim, disability, and lawsuit) was found in 26 of 27 (96.3%) of NOVL patients wearing sunglasses and in none of the sunglasses patients with organic neuro-ophthalmic disorders. All 7 sunglasses patients with organic neuro-ophthalmic disorders had reasonable ophthalmic explanations for wearing sunglasses. CONCLUSION: The "sunglasses sign" in a patient without an obvious ophthalmic reason to wear sunglasses is highly suggestive of nonorganic visual loss.

Traumatic homonymous hemianopia.

OBJECTIVE: To describe the characteristics of patients with homonymous hemianopia from traumatic brain injury (TBI) seen in our unit between 1989 and 2004. METHODS: Only patients with a history of TBI, who had detailed clinical information and results of neuroimaging, were included in our study. Demographic characteristics, clinical features, types of visual field defects, location of lesion and evolution of visual field defects were recorded. RESULTS: Of the 880 patients with homonymous hemianopia seen in our unit, 103 patients (112 with homonymous hemianopia) had TBI (74 men and 29 women, mean age 30.7 (SD 15.3) years). Median time from injury to initial visual field testing was 5 (range 0.5-360) months. In all, 64 (57.1%) patients sustained injuries that were motor vehicle-related; 19 (17%) violence-related; 17 (15.2%) due to falls; and 12 (10.7%) because of other blunt head trauma. Visual field defects included complete homonymous hemianopia in 44 (39.3%) patients and incomplete homonymous hemianopia in 68 (60.7%) patients. The lesion was occipital in 14 (12.5%) patients, associated with optic radiation in 26 (23.2%) and the optic tract in 12 (10.7%), and multiple in 60 (53.6%). CONCLUSION: Most cases of homonymous hemianopia from TBI were motor vehicle-related. Patients were younger, more often male, and had multiple brain lesions more often than patients with homonymous hemianopia from causes other than TBI. A median delay of 5 months was observed before the documentation of the homonymous hemianopia, which may have a major effect on the success of rehabilitation and driving training in these young patients.

Natural history of homonymous hemianopia.

OBJECTIVE: To describe the characteristics of spontaneous recovery of homonymous hemianopia (HH). METHODS: The authors reviewed medical records of all patients with HH confirmed by formal visual field testing and seen in follow-up in their service between 1989 and 2004. Clinical characteristics, causes, neuroradiologic definition of lesion location, final outcome, and evolution of the visual field defects were recorded. The associations among final visual field defect outcome, time from injury, and clinical features were analyzed. RESULTS: A total of 254 patients with 263 HH were included in this study. Spontaneous visual field defect recovery was observed in 101 HH (38.4%). The likelihood of spontaneous recovery decreased with increasing time from injury to initial visual field testing (p = 0.0003). The probability of improvement was related to the time since injury (p = 0.0003) with a 50 to 60% chance of improvement for cases tested within 1 month after injury that decreased to about 20% for cases tested at 6 months after surgery. No other factor was found to correlate with the final outcome of the visual field defects. Improvement after 6 months from injury was mild and usually related to improvement of the underlying disease. CONCLUSION: Spontaneous improvement of homonymous hemianopia is seen in at least 50% of patients first seen within 1 month of injury. In most cases, the improvement occurs within the first 3 months from injury. Spontaneous improvement after 6 months postinjury should be interpreted with caution as it is most likely related to improvement of the underlying disease or to improvement in the patient's ability to perform visual field testing reliably.

Homonymous hemianopias: clinical-anatomic correlations in 904 cases.

OBJECTIVE: To describe the clinical characteristics and clinical-anatomic correlations of homonymous hemianopia (HH). BACKGROUND: Homonymous hemianopia impairs visual function and frequently precludes driving. Most knowledge of HH is based on relatively few cases with clinical-anatomic correlations. METHODS: The authors reviewed medical records of all patients with HH seen in their service between 1989 and 2004. Demographic characteristics, characteristics of visual field defects, causes of visual field defects, neuroradiologic definition of lesion location, and associated neurologic deficits were recorded. RESULTS: A total of 904 HH were found in 852 patients. A total of 340 HH (37.6%) were complete and 564 HH (62.4%) were incomplete. Homonymous quadrantanopia (264 HH, 29%) was the most common type of incomplete HH, followed by homonymous scotomatous defects (116 HH, 13.5%), partial HH (114 HH, 13%), and HH with macular sparing (66 HH, 7%). A total of 407 HH (45.0%) were isolated. Causes of HH included stroke (629 HH, 69.6%), trauma (123, 13.6%), tumor (102, 11.3%), brain surgery (22, 2.4%), demyelination (13, 1.4%), other rare causes (13, 1.4%), and unknown etiology (2, 0.2%). The lesions were most commonly located in the occipital lobes (45%) and the optic radiations (32.2%). Every type of HH, except for unilateral loss of temporal crescent and homonymous sectoranopia, was found in all lesion locations along the retrochiasmal visual pathways. CONCLUSION: Homonymous hemianopia is usually secondary to stroke, head trauma, and tumors. Although the characteristics of visual field defects can be helpful in lesion location, specific visual field defects do not always indicate specific brain locations.

Progressive outer retinal necrosis presenting with isolated optic neuropathy.

Progressive outer retinal necrosis is a necrotizing herpetic retinopathy usually seen in immunocompromised patients. The authors describe two patients with this disease who initially had findings suggestive of an optic neuropathy. Vision declined after treatment with methylprednisolone, after which fundus examination became consistent with progressive outer retinal necrosis. These cases underscore the importance of careful examination of the retinal periphery before management of any presumed optic neuropathy with steroids.

Hereditary optic neuropathies.

AIMS: To provide a clinical update on the hereditary optic neuropathies. METHODS: Review of the literature. RESULTS: The hereditary optic neuropathies comprise a group of disorders in which the cause of optic nerve dysfunction appears to be hereditable, based on familial expression or genetic analysis. In some hereditary optic neuropathies, optic nerve dysfunction is typically the only manifestation of the disease. In others, various neurologic and systemic abnormalities are regularly observed. CONCLUSION: The most common hereditary optic neuropathies are autosomal dominant optic atrophy (Kjer's disease) and maternally inherited Leber's hereditary optic neuropathy. We review the clinical phenotypes of these and other inherited disorders with optic nerve involvement.

The use of contact lenses to treat visually symptomatic congenital nystagmus.

It has been suggested that contact lens wear improves the visual function of patients with visual loss from congenital nystagmus. In this study, four patients with congenital nystagmus had two evaluations separated by at least one week (one with spectacles, one with contact lenses) including visual acuity, contrast sensitivity, oscillopsia scale, quality of life questionnaire (NEI VFQ-25), and eye movement recording with an infrared tracking system. All patients subjectively preferred contact lenses to spectacles. Their contrast sensitivity and VFQ-25 scores were improved with contact lenses compared with spectacles alone. Several parameters of nystagmus showed no change in two patients, worsening in one patient and improvement in one patient. This suggests that much of the clinical improvement observed in our patients may result from a better optical correction of their refractive error with contact lenses than with spectacles, rather than from a true damping effect of the nystagmus by contact lenses.