Binasal congruous hemianopia secondary to functional visual loss: A case report.

INTRODUCTION: To describe an unusual case of binasal congruous hemianopia secondary to functional visual loss (FVL). PATIENT CONCERNS: A 24 year-old male was referred originally by his optician at the Emergency Eye Department of the Leicester Royal Infirmary in October 2018 with visual field changes affecting the nasal field of vision in both eyes on routine eye examination. The patient reported ongoing headaches over the last 6 weeks to 8 weeks associated with simultaneous peripheral visual field changes. He also reported rapid loss of weight over the same period of time. DIAGNOSIS: Binasal congruous hemianopia secondary to FVL. INTERVENTIONS: Full past medical and ocular history was obtained. The patient underwent full ophthalmic examination including dilated fundoscopy. Visual acuity was recorded with Snellen Chart. Color vision was assessed with Ishihara plates. Peripheral vision was assessed with both Humphrey visual fields and Goldmann visual fields. Optical coherence tomography of the macula and discs was also performed. Neuroimaging investigations included Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) of the Brain. Electrophysiology investigations included Electroretinogram and visual evoked potentials. Patient was also tested for syphilis. OUTCOMES: Humphrey visual fields and Goldmann visual fields confirmed the presence of complete binasal field defects. Optical coherence tomography, electroretinogram, visual evoked potentials, CT, MRI were all unremarkable. Ocular examination was normal. Finally, syphilis serology was negative. After 1 year of follow-up, the visual field changes have remained the same. CONCLUSION: To the best of our knowledge, this is the fourth case described in the literature with complete congruous binasal hemianopia due to FVL. We advocate thorough investigations with multimodal imaging of the fundus, neuroimaging and syphilis serology to exclude serious organic causes for binasal field defects prior to labeling such a field defect functional. Such patients may benefit from neuropsychological input to understand the psychological factors that may be contributing to the symptoms.

Anti-NMDA-receptor encephalitis presenting with catatonia and neuroleptic malignant syndrome in patients with intellectual disability and autism.

We report anti-N-methyl-d-aspartate (NMDA) receptor encephalitis in two patients with autism and intellectual disability presenting with neuropsychiatric symptoms of catatonia and neuroleptic malignant syndrome. Case reports such as these help raise awareness of this clinical issue. By paving the way for earlier diagnoses they ultimately maximise the potential for curative treatments and prevention of long-term complications.

Morphology of retinal vessels in patients with optic nerve head drusen and optic disc edema.

PURPOSE: We quantitatively investigated the peripapillary vascular morphology in patients with optic nerve head drusen (ONHD) and optic disc edema (ODE). METHODS: Computer-based fundus analysis was used to investigate peripapillary vascular morphology, including length, branching, and diameter of arteries and veins calibrated by optical coherence tomography. RESULTS: Patients with ONHD showed significantly larger diameters of arteries without branching (P = 0.05), and arteries after primary/before secondary branching (P = 0.04) and secondary venous branching started closer to the optic disc (P = 0.03) compared to healthy controls. The ODE patients had significantly reduced number of small peripapillary veins and larger number of veins without branching compared to ONHD and controls (P = 0.02). Anomalous branching with arterial and venous trifurcation presented in the ODE and ONHD groups, with significant higher prevalence in ODE patients for venous trifurcations compared to ONHD and controls (P = 0.02). CONCLUSIONS: The diameter of vessels in ONHD patients were significantly larger in arteries without branching (P = 0.05), after primary branching (P = 0.04), and venous branching closer to the disc area (P = 0.03) compared to controls. The ODE patients demonstrated widening of the small peripapillary veins measured by a significantly larger number of veins without branching (P = 0.001 and P = 0.02, compared to controls and ONHD, respectively) and less small veins (P = 0.001 and P = 0.04, compared to controls and ONHD, respectively).

Rating papilloedema: an evaluation of the Frisén classification in idiopathic intracranial hypertension.

The appearance of the optic disc is a key measure of disease status in idiopathic intracranial hypertension (IIH). The Frisén classification describes stages of optic disc swelling (grades 0-5). It is the only classification of papilloedema, and is used internationally in clinical and research practice. Despite this, there has been very limited evaluation of the scale. We assessed the inter-rater reproducibility and ability to discriminate optic disc changes over time using the Frisén classification compared with a system of ranking papilloedema severity in patients with IIH. Paired disc photographs (before and after treatment) were obtained from 47 patients with IIH (25 acute and 22 chronic). Six neuro-ophthalmologists blinded to patient identity, clinical information and chronology of the photographs reviewed the discs and allocated a Frisén grade and ranked the paired discs in order of papilloedema severity (disc ranking). A total of 188 optic disc photographs were reviewed. All six reviewers agreed in only three comparisons (1.6%) when using the Frisén classification, compared with 42 comparisons (45.2%) when using disc ranking. The probability of agreement between any two reviewers was 36.1% for Frisén grade and 70.0% for disc ranking. Disc ranking had significantly greater sensitivity for finding differences in degree of disc oedema, identifying a difference in 75.3% of paired photographs compared to 53.2% detected using the Frisén classification (p < 0.001). This study demonstrated the limited reproducibility and discriminative ability of the Frisén classification in identifying changes in serial optic disc photographs in IIH. Simple optic disc ranking appears to be a more sensitive and reliable tool to monitor changes in optic disc appearance. The use of disc ranking in clinical practice and research studies is recommended to monitor alterations in optic disc appearance until alternative schemes, specific to IIH, have been developed.

Melanoma associated retinopathy and how to understand the electroretinogram.

Melanoma associated retinopathy is a rare paraneoplastic complication of metastatic cutaneous malignant melanoma. It may present years after the original diagnosis of melanoma. Here we describe a patient with this condition who presented with persistent photopsias and visual loss. We will discuss the electroretinographic findings and their utility.

A randomised controlled trial of treatment for idiopathic intracranial hypertension.

The cause of idiopathic intracranial hypertension (IIH) remains unknown, and no consensus exists on how patients should be monitored and treated. Acetazolamide is a common treatment but has never been examined in a randomised controlled trial. The objectives of this pilot trial are to prospectively evaluate the use of acetazolamide, to explore various outcome measures and to inform the design of a definitive trial in IIH. Fifty patients were recruited from six centres over 23 months and randomised to receive acetazolamide (n = 25) or no acetazolamide (n = 25). Symptoms, body weight, visual function and health-related quality-of-life measures were recorded over a 12-month period. Recruited patients had typical features of mild IIH and most showed improvement, with 44% judged to have IIH in remission at the end of the trial. Difficulties with recruitment were highlighted as well as poor compliance with acetazolamide therapy (12 patients). A composite measure of IIH status was tested, and the strongest concordance with final disease status was seen with perimetry (Somers' D = 0.66) and optic disc appearance (D = 0.59). Based on the study data, a sample size of 320 would be required to demonstrate a 20% treatment effect in a substantive trial. Clinical trials in IIH require pragmatic design to involve sufficiently large numbers of patients. Future studies should incorporate weighted composite scores to reflect the relative importance of common outcome measures in IIH.

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 H(2)O), 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 H(2)O, 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) micro, 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.

Altered mental state and the Whipple triad.

A 47-year-old man presented with episodes of altered mental state initially felt to be complex partial seizures, but which were in fact hypoglycaemic episodes. An insulinoma was confirmed and eventually localised. He underwent an abdominal computed tomography scan and intraoperative laparoscopy, but required selective venous sampling to localise the tumour. Fifteen months after his surgery there is no evidence of recurrence of his insulinoma.

Paroxysmal extreme pain disorder M1627K mutation in human Nav1.7 renders DRG neurons hyperexcitable.

BACKGROUND: Paroxysmal extreme pain disorder (PEPD) is an autosomal dominant painful neuropathy with many, but not all, cases linked to gain-of-function mutations in SCN9A which encodes voltage-gated sodium channel Nav1.7. Severe pain episodes and skin flushing start in infancy and are induced by perianal probing or bowl movement, and pain progresses to ocular and mandibular areas with age. Carbamazepine has been effective in relieving symptoms, while other drugs including other anti-epileptics are less effective. RESULTS: Sequencing of SCN9A coding exons from an English patient, diagnosed with PEPD, has identified a methionine 1627 to lysine (M1627K) substitution in the linker joining segments S4 and S5 in domain IV. We confirm that M1627K depolarizes the voltage-dependence of fast-inactivation without substantially altering activation or slow-inactivation, and inactivates from the open state with slower kinetics. We show here that M1627K does not alter development of closed-state inactivation, and that M1627K channels recover from fast-inactivation faster than wild type channels, and produce larger currents in response to a slow ramp stimulus. Using current-clamp recordings, we also show that the M1627K mutant channel reduces the threshold for single action potentials in DRG neurons and increases the number of action potentials in response to graded stimuli. CONCLUSION: M1627K mutation was previously identified in a sporadic case of PEPD from France, and we now report it in an English family. We confirm the initial characterization of mutant M1627K effect on fast-inactivation of Nav1.7 and extend the analysis to other gating properties of the channel. We also show that M1627K mutant channels render DRG neurons hyperexcitable. Our new data provide a link between altered channel biophysics and pain in PEPD patients.

Optic nerve sheath fenestration for intracranial hypertension associated with chronic inflammatory demyelinating polyneuropathy.

The authors report a case of papilledema in a 61-year-old woman with chronic demyelinating polyneuropathy. The cerebrospinal fluid protein level was elevated (2.68 to 4.51 g/L), as was the cerebro-spinal fluid opening pressure (27 to 40 cm H2O). A unilateral optic nerve sheath fenestration proved to be effective in preserving vision, and the papilledema resolved completely.