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Purpose: To describe 2 adult patients who presented with papilledema after band atrophy (i.e., twin and triple peaks papilledema). Design: Retrospective small case series. Participants: Two outpatients. Methods: Observations made on 2 patients whose cases were reviewed in the neuro-ophthalmology clinic. Results: The first patient had a pituitary tumor presenting with papilledema, causing a triple peaks clinical sign. Color photographs, optical coherence tomograms, and magnetic resonance images are shown. The second patient developed twin peaks papilledema due to a chiasmal glioma causing secondary raised intracranial pressure. Conclusion: Twin peaks papilledema is a rare clinical sign that may develop in adults as well as in children. The first report and optical coherence tomography features of triple peaks papilledema illustrate a new clinical sign. [Copyright &y& Elsevier]

Tuberculosis (TB) may affect the nervous system in many ways. We describe an immunocompetent teenage girl with lymph node TB who had first presented with bilateral optic neuritis. Detailed history identified features inconsistent with immune-mediated optic neuritis. Several unusual features prompted further investigation, including transient visual obscurations without raised intracranial pressure, prominent disc swelling and absence of laboratory findings to support an immune- mediated cause. Whole body PET/ MR imaging identified widespread mediastinal and supraclavicular lymphadenopathy. Despite no known TB contacts, a negative interferon gamma release assay and a normal chest X-ray, a targeted lymph node biopsy confirmed TB. [ABSTRACT FROM AUTHOR]

Following damage to the human post-geniculate visual pathway retrograde trans-synaptic degeneration of the optic nerve fibres occurs. It has been known for some time from investigations carried out in primates that a decline in the number of retinal ganglion cells follows occipital lobectomy. However, this is not detectable in all species studied and whether this occurs in humans was controversial until recent studies that have shown that following lesions of the occipital lobe, the retinal nerve fibre layer thickness measured by optical coherence tomography is reduced and corresponding shrinkage of the optic tract can be demonstrated by magnetic resonance imaging. The time course of the degeneration in humans is, however, unknown. In the present study, we have used optical coherence tomography to demonstrate for the first time progressive thinning of the retinal nerve fibre layer following occipital lobe/optic radiation damage due to stroke. First, in a group of 38 patients the measurement was taken on a single occasion at a known time interval since the stroke, ranging from 6 days to 67 years. Here, a negative straight line relationship (linear regression r = 0.54, P < 0.001) was found between nerve fibre layer thickness and elapsed time since injury in log years, giving a rate of decline of 9.08 µm per log year after adjusting for age. This indicates a decelerating rate of loss that differs from the rate of decline found with chronological age in this same group, which shows a steady rate of thinning by 0.4 µm per year (P = 0.006) after adjusting for duration of the disease. In a second study serial measurements were taken following the acute event in a group of seven patients with homonymous hemianopia; here a negative straight line relationship was found between time and nerve fibre layer thickness in micrometres over a period of data collection beginning at a mean of 36.9 days post-stroke (range 5–112) and ending at a mean of 426.6 days post-stroke (range 170–917). Evidence from clinical observation (funduscopy) suggested that retrograde trans-synaptic degeneration occurred in humans only where the damage to the post-geniculate pathway occurred prenatally. The results reported herein add weight to the previous demonstration that this type of degeneration does indeed occur in the human visual system by showing that it can be monitored over time and hence may provide a model for trans-synaptic degeneration in the human central nervous system. [ABSTRACT FROM PUBLISHER]

The article presents a case study of a 52-year-old man with a history of myocardial infarction presented with difficulty in focusing. Physical examination, magnetic resonance imaging (MRI), and positron emission tomography scan results led to the diagnosis of Parinaud's syndrome, which developed as part of paraneoplastic limbic encephalitis. High-dose methylprednisolone and intravenous immunoglobulin were administered, pharyngeal lesion was removed surgically after which the patient stabilised. INSET: Learning points.

Objectives: Conventional and quantitative MRI was performed in patients with chronic progressive external ophthalmoplegia (CPEO), a common manifestation of mitochondrial disease, to characterise MRI findings in the extra-ocular muscles (EOMs) and investigate whether quantitative MRI provides clinically relevant measures of disease.Methods: Patients with CPEO due to single mitochondrial DNA deletions were compared with controls. Range of eye movement (ROEM) measurements, peri-orbital 3 T MRI T1-weighted (T1w) and short-tau-inversion-recovery (STIR) images, and T2 relaxation time maps were obtained. Blinded observers graded muscle atrophy and T1w/STIR hyperintensity. Cross-sectional areas and EOM mean T2s were recorded and correlated with clinical parameters.Results: Nine patients and nine healthy controls were examined. Patients had reduced ROEM (patients 13.3°, controls 49.3°, p < 0.001), greater mean atrophy score and increased T1w hyperintensities. EOM mean cross-sectional area was 43 % of controls and mean T2s were prolonged (patients 75.6 ± 7.0 ms, controls 55.2 ± 4.1 ms, p < 0.001). ROEM correlated negatively with EOM T2 (rho = -0.89, p < 0.01), whilst cross-sectional area failed to correlate with any clinical measures.Conclusions: MRI demonstrates EOM atrophy, characteristic signal changes and prolonged T2 in CPEO. Correlation between elevated EOM T2 and ROEM impairment represents a potential measure of disease severity that warrants further evaluation.Key Points: Chronic progressive external ophthalmoplegia is a common clinical manifestation of mitochondrial disease. • Existing extra-ocular muscle MRI data in CPEO reports variable radiological findings. MRI confirmed EOM atrophy and characteristic signal changes in CPEO. EOM T2 was significantly elevated in CPEO and correlated negatively with ocular movements. EOM T2 represents a potential quantitative measure of disease severity in CPEO. [ABSTRACT FROM AUTHOR]

Background Non-arteritic anterior ischaemic optic neuropathy (NA-AION) can cause disabling visual loss and traditionally, visual prognosis has been considered poor, although recent studies have demonstrated improvements in visual acuity in about 30% of patients over time. The aim of the study was to determine whether there was significant cortical reorganisation with functional MRI (fMRI) after acute NA-AION by comparing affected individuals with healthy controls. Methods 9 patients with NA-AION were studied acutely and then after 1, 2, 3 and 6 months. 23 healthy volunteers underwent scanning at least twice. At each time point, patients were assessed clinically and with fMRI. For the fMRI experiments, subjects underwent monocular visual stimulation (wearing goggles with flashing LED displays). Results When stimulating the affected eye, occipital activation was reduced in patients compared with controls. Also, within the NA-AION group, activation in the right Brodmann areas (BA) 44 and 45 was seen during the early phase of the condition. The same areas were activated within the NA-AION group several months later for fellow eye stimulation. When the NA-AION and healthy control groups were formally compared however, these areas (BA 44/45) were not significantly different. NA-AION subjects did show greater activation in visual related areas compared with controls when stimulating the fellow eye. Visual acuity was correlated with more occipital cortex activation when stimulating the affected eye. Conclusions There is cortical re-organisation of the fMRI response in extra-visual areas, seen when both affected and fellow eyes are stimulated after NA-AION. [ABSTRACT FROM AUTHOR]

Background: The 2001 and 2005 McDonald criteria allow MRI evidence for dissemination in space (DIS) and dissemination in time (DIT) to be used to diagnose multiple sclerosis in patients who present with clinically isolated syndromes (CIS). In 2006, new criteria were proposed in which DIS requires at least one T2 lesion in at least two of four locations (juxtacortical, periventricular, infratentorial, and spinal-cord) and DIT requires a new T2 lesion on a follow-up scan. We applied all three criteria in a large cohort of CIS patients to assess their performance by use of conversion to clinically definite multiple sclerosis (CDMS) as the outcome.Methods: Patients who had two MRI scans within 12 months of CIS onset were identified in four centres in the Magnims European research network. The specificity and sensitivity of MRI criteria for CDMS after 3 years was assessed in 208 patients. A Cox proportional hazards model was applied in a larger cohort of 282 patients that included all patients irrespective of length of follow-up.Findings: The specificity of all criteria for CDMS was high (2001 McDonald, 91%; 2005 McDonald, 88%; new, 87%). Sensitivity of the new (72%) and 2005 McDonald (60%) criteria were higher than the 2001 McDonald criteria (47%). The Cox proportional hazards model showed a higher conversion risk for all three criteria in those with both DIS and DIT than those with either DIS or DIT alone. When all three criteria were included in the model, only the new criteria had an independent significant effect on conversion risk.Interpretation: The new criteria are simpler than the McDonald criteria without compromising specificity and accuracy. The presence of both DIS and DIT from two MRI scans has a higher specificity and risk for CDMS than either DIS or DIT alone. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic resonance imaging (MRI) measures of brain atrophy are often considered to be a marker of axonal loss in multiple sclerosis (MS) but evidence is limited. Optic neuritis is a common manifestation of MS and results in optic nerve atrophy. Retinal nerve fibre layer (RNFL) imaging is a non-invasive way of detecting axonal loss following optic neuritis. We hypothesise that if the optic nerve atrophy that develops following optic neuritis is contributed to by axonal loss, it will correlate with thinning of the RNFL. Twenty-five patients were studied at least 1 year after a single unilateral attack of optic neuritis without recurrence, with a selection bias towards incomplete recovery. They had MR quantification of optic nerve cross-sectional area and optic nerve lesion length, as well as optical coherence tomography (OCT) measurement of mean RNFL thickness and macular volume, quantitative visual testing, and visual evoked potentials (VEPs). Fifteen controls were also studied. Significant optic nerve atrophy (mean decrease 30% versus controls), RNFL thinning (mean decrease 33% versus controls), and macular volume loss occurred in patients'' affected eyes when compared with patients'' unaffected eyes and healthy controls. The optic nerve atrophy was correlated with the RNFL thinning, macular volume loss, visual acuity, visual field mean deviation, and whole field VEP amplitude but not latency. These findings suggest that axonal loss contributes to optic nerve atrophy following a single attack of optic neuritis. By inference, axonal loss due to other post-inflammatory brain lesions is likely to contribute to the global MRI measure of brain atrophy in multiple sclerosis. [Copyright &y& Elsevier]

Abstract: Diffusion tensor magnetic resonance imaging (DT-MRI) provides in vivo information about the pathology of multiple sclerosis lesions. Increases in mean diffusivity (MD) and reductions in fractional anisotropy (FA) have been found and may represent axonal disruption. The optic nerve is an ideal structure for study by DT-MRI but previous clinical studies did not obtain the full diffusion tensor necessary to calculate MD and FA. In this study, a technique that was specifically developed to achieve full diffusion tensor measurements from the optic nerve (zonal oblique multislice (ZOOM) echoplanar imaging) was applied to 25 patients with a single unilateral episode of optic neuritis at least one year previously, and 15 controls. The intraorbital nerves were segmented on non-diffusion-weighted images and the regions of interest transferred to MD, FA, and eigenvalue maps to obtain quantitative data. Quantitative visual testing and electrophysiology were also performed. In affected nerves, mean MD and mean orthogonal eigenvalue λ ⊥ were elevated, and mean FA reduced compared with clinically unaffected contralateral nerves (P < 0.001) and control nerves (P < 0.001). The mean principal eigenvalue λ \\ was significantly increased in affected nerves compared to contralateral unaffected nerves (P = 0.04) but not compared to control nerves (P = 0.13). There was no association of clinical measures of visual function in affected eyes with the DT-MRI parameters but there was a significant correlation of the whole field visual evoked potential (VEP) amplitude with MD (r = −0.57, P = 0.006) and λ ⊥ (r = −0.56, P = 0.007). These findings suggest that optic nerve DT-MRI measures provide an indication of the structural integrity of axons. [Copyright &y& Elsevier]

This study reports the prospective follow–up of a cohort of patients with acute optic neuritis examined with serial visual tests, visual evoked potentials (VEPs), conventional and triple–dose gadolinium (Gd)–enhanced magnetic resonance imaging (MRI) to examine which factors are important in visual recovery. Thirty–three patients were recruited with acute unilateral optic neuritis. A clinical and VEP assessment was performed on each. Optic nerve MRI was performed using fast spin echo (FSE) (on all) and triple-dose Gdenhanced T1–weighted sequences (n = 28). Optic nerve lesion lengths were measured. Serial assessments were performed on 22 of the patients up to one–year. Serial Gd–enhanced optic nerve imaging was performed on 15 of the patients until enhancement ceased. The final 30–2 Humphrey visual field mean deviation (MD) was 2.55 dB higher in patients in the lowest quartile of initial Gd–enhanced lesion length compared with the other quartiles (p < 0.01) but recovery was not related to the duration of enhancement. The initial recovery of Humphrey MD was 4.60 dB units per day in patients with good eventual recoveries (MD > –6.0 dB) and 0.99 dB per day in poor-recovery patients (p = 0.02).Good–recovery patients had mean central field VEP amplitudes 2.29 µV higher during recovery than poor-recovery patients (p = 0.047). The results suggest that factors which are associated with a better prognosis are: having a short acute lesion on triple–dose gadolinium enhanced imaging, higher VEP amplitudes during recovery and a steep gradient of the initial improvement in vision. [ABSTRACT FROM AUTHOR]

As there is little information regarding the recovery from Uhthoff phenomenon (UP) in the multiple sclerosis (MS) literature, the objective of this study was to assess the phenotypes of UP. A one-page questionnaire was sent to 80 consecutive optic neuritis (ON) patients seen in a tertiary neuro-ophthalmology clinic. Of the 48 responders to the questionnaire, 52% reported experiencing UP, with a range of follow-up from 1 to 20 years. Only 16% had resolution of UP, all this occurred within 8 weeks of the onset of ON. Of the MS patients with UP, 88% experienced non-visual heat-related phenomenon compared with 30% without UP. The presence of UP may have a more general phenotypic significance. If full recovery from UP has not occurred within the first 2 months from the onset of ON, then recovery appears to be uncommon and may therefore be a surrogate marker of remyelination in future drug trials. [ABSTRACT FROM PUBLISHER]