Revised diagnostic criteria for neuromyelitis optica

BACKGROUND

The authors previously proposed diagnostic criteria for neuromyelitis optica (NMO) that facilitate its distinction from prototypic multiple sclerosis (MS). However, some patients with otherwise typical NMO have additional symptoms not attributable to optic nerve or spinal cord inflammation or have MS-like brain MRI lesions. Furthermore, some patients are misclassified as NMO by the authors' earlier proposed criteria despite having a subsequent course indistinguishable from prototypic MS. A serum autoantibody marker, NMO-IgG, is highly specific for NMO. The authors propose revised NMO diagnostic criteria that incorporate NMO-IgG status.

METHODS

Using final clinical diagnosis (NMO or MS) as the reference standard, the authors calculated sensitivity and specificity for each criterion and various combinations using a sample of 96 patients with NMO and 33 with MS. The authors used likelihood ratios and logistic regression analysis to develop the most practical and informative diagnostic model.

RESULTS

Fourteen patients with NMO (14.6%) had extra-optic-spinal CNS symptoms. NMO-IgG seropositivity was 76% sensitive and 94% specific for NMO. The best diagnostic combination was 99% sensitive and 90% specific for NMO and consisted of at least two of three elements: longitudinally extensive cord lesion, onset brain MRI nondiagnostic for MS, or NMO-IgG seropositivity.

CONCLUSIONS

The authors propose revised diagnostic criteria for definite neuromyelitis optica (NMO) that require optic neuritis, myelitis, and at least two of three supportive criteria: MRI evidence of a contiguous spinal cord lesion 3 or more segments in length, onset brain MRI nondiagnostic for multiple sclerosis, or NMO-IgG seropositivity. CNS involvement beyond the optic nerves and spinal cord is compatible with NMO.

The clinical course of neuromyelitis optica (Devic's syndrome)

OBJECTIVES

To evaluate the spectrum of neuromyelitis optica (NMO), including characteristics of the index events (optic neuritis [ON]) and myelitis), neuroimaging, CSF, and serologic studies, and to evaluate the long-term course.

METHODS

Review of 71 patients with NMO evaluated at the Mayo Clinic between 1950 and 1997.

RESULTS

NMO was either monophasic or relapsing. Patients with a monophasic course (n = 23) usually presented with rapidly sequential index events (median 5 days) with moderate recovery. Most with a relapsing course (n = 48) had an extended interval between index events (median 166 days) followed within 3 years by clusters of severe relapses isolated to the optic nerves and spinal cord. Most relapsing patients developed severe disability in a stepwise manner, and one-third died because of respiratory failure. Features of NMO distinct from "typical" MS included >50 cells/mm3 in CSF (often polymorphonuclear), normal initial brain MRI, and lesions extending over three or more vertebral segments on spinal cord MRI.

CONCLUSIONS

Clinical, laboratory, and imaging features generally distinguish neuromyelitis optica from MS. Patients with relapsing optic neuritis and myelitis may have neuromyelitis optica rather than MS. Patients with a relapsing course of neuromyelitis optica have a poor prognosis and frequently develop respiratory failure during attacks of cervical myelitis.

The natural history of multiple sclerosis: a geographically based study 9: observations on the progressive phase of the disease

The clinical features of relapses and progression largely define multiple sclerosis phenotypes. A relapsing course is followed by chronic progression in some 80% of cases within 2 decades. The relationship between these phases and long-term outcome remains uncertain. We have analysed these clinical features within a well-studied natural history cohort with mean follow-up of 25 years. For the entire cohort, median times to reach Disability Status Scale (DSS) 6, 8 and 10 were 12.7, 20.6 and 43.9 years, respectively. Among 824 attack-onset patients, the great majority entered a progressive phase with a mean time to progression of 10.4 years. The effects of relapses often cloud the clinical onset of progression. However, there are circumstances where onset of progression is early, relatively discrete and identifiable at DSS of 2 or less. Three subgroups allow for clarity of outcome comparison and they are (i) cases of primary progressive (PP) disease, (ii) attack-onset disease where only a single attack has occurred before onset of progression (SAP) and (iii) secondary progressive (SP) disease where recovery from relapses allows recognition of the earliest clinical stages when progression begins. Here we compare survival curves in these three groups. Among cohorts of SAP (n = 140), PP (n = 219) and SP (n = 146) where progression was stratified by DSS at its onset, there was no difference in time to DSS 6, 8 and 10. These findings demonstrate that the progressive course is independent of relapses either preceding the onset of relapse-free progression or subsequent to it. Among SAP patients, the degree of recovery from the single defining exacerbation had no significant effect on outcome. The site of the original attack was not usually where progression began. The relatively stereotyped nature of the progressive phase seen in all progressive phenotypes suggests regional and/or functional differential susceptibility to a process that appears degenerative in nature. The highly prevalent distal corticospinal tract dysfunction in progressive disease and the pathologically demonstrated selective axonal loss seen in this tract raises the possibility of a dying back central axonopathy, at least in part independent of plaque location or burden. Despite considerable individual variation, the progressive course of disability seen in groups of PP, SAP and SP-DSS2 is similarly stereotyped in quality and pace and may entail mechanisms common to all forms of progressive multiple sclerosis. The possibility that this is the primary process in some cases must be considered.

NMO-IgG predicts the outcome of recurrent optic neuritis

OBJECTIVE

To determine the prognostic value of neuromyelitis optica (NMO)-immunoglobulin G (IgG) in patients with recurrent optic neuritis (ON). The aquaporin-4-specific serum autoantibody, NMO-IgG, is a biomarker for NMO and relapsing transverse myelitis. Recurrent ON may herald multiple sclerosis (MS) or NMO, or it may occur as an isolated syndrome. The prognosis and response to therapy differs in each of these contexts.

METHODS

We evaluated 34 patients who were tested for NMO-IgG between 2000 and 2007 and who had two or more episodes of ON without satisfying a diagnosis of MS or NMO prior to serologic testing. Clinical data were available for 25 Mayo Clinic patients (5 NMO-IgG positive and 20 NMO-IgG negative) and for an additional 9 seropositive patients whose serum was referred to the Mayo Clinic Neuroimmunology laboratory for testing.

RESULTS

Twenty percent of the patients with recurrent ON seen at Mayo Clinic were seropositive. All NMO-IgG-positive patients (vs 65% NMO-IgG-negative patients) had at least one attack with visual acuity in the affected eye worse than 20/200 (p = 0.05). In seropositive patients for whom long-term follow-up was possible (median 8.9 years after the initial ON), 6 of 12 (50%) experienced an episode of myelitis and fulfilled criteria for NMO. In contrast, 1 of 15 seronegative patients (6.7%) fulfilled McDonald criteria for MS (p = 0.03). Seropositive patients had a final visual score which was worse than that of seronegative patients (p = 0.02).

CONCLUSIONS

Neuromyelitis optica (NMO)-immunoglobulin G seropositivity predicts poor visual outcome and development of NMO. Seropositive recurrent optic neuritis is a limited form of NMO.

A secondary progressive clinical course is uncommon in neuromyelitis optica

We compared the clinical course of 96 patients with neuromyelitis optica (NMO) to multiple sclerosis (MS) natural history data. Based on the distribution of follow-up data (median 6.1 year), we estimated that 21 NMO patients would convert to a secondary progressive course, but we observed only two conversions (p = 0.00002; relative risk = 0.08). The disparate natural histories of MS and NMO suggest dissociation between relapses and clinical progression in CNS demyelinating diseases.

Multiple sclerosis: current pathophysiological concepts

Multiple sclerosis (MS) is an often disabling disease primarily affecting young adults that exhibits extraordinary clinical, radiological, and pathological heterogeneity. We review the following: (a) known environmental and genetic factors that contribute to MS susceptibility; (b) current knowledge regarding fundamental pathophysiological processes in MS, including immune cell recruitment and entry into the central nervous system (CNS), formation of the plaque, and orchestration of the immune response; (c) descriptive and qualitative distinct pathological patterns in MS and their implications; (d) the evidence supporting the causative role of direct toxins, cell-mediated and humorally mediated immune mechanisms, and the concept of a "primary oligodendrogliopathy" in demyelination and axonal injury; (e) the potential benefits of inflammation; (f) the prospects for remyelination; and (g) therapeutic implications and approaches suggested by putative pathophysiological mechanisms.

A pilot study of oral calcitriol (1,25-dihydroxyvitamin D3) for relapsing-remitting multiple sclerosis

BACKGROUND

Epidemiological and ecological studies suggest links between vitamin D deficiency and increased multiple sclerosis (MS) prevalence.

OBJECTIVE

To evaluate the safety and tolerability of oral calcitriol therapy in an open label pilot study.

METHODS

15 ambulatory patients with relapsing-remitting MS and at least one clinical relapse within the previous 12 months received oral calcitriol (target dose: 2.5 microg/d) for 48 weeks. Dietary calcium was restricted to 800 mg/d. Patients were monitored using frequent clinical and laboratory examinations, the expanded disability status scale (EDSS), and brain magnetic resonance imaging (MRI).

RESULTS

Two patients withdrew because of symptomatic hypercalcaemia (serum calcium >3.35 mmol/l in each case) resulting from persistent dietary indiscretion. Two diet compliant patients required temporary dose adjustments for mild asymptomatic hypercalcaemia. Diet compliant patients experienced mild adverse effects. The on-study exacerbation rate (27%) was less than baseline. Four patients experienced five clinical relapses but only one patient worsened by >1 EDSS point. Brain MRI revealed enhancing lesions in five patients at baseline (33%) and in four (29%) at both 24 and 48 weeks.

CONCLUSIONS

Oral calcitriol is safe and well tolerated for up to one year by diet compliant relapsing-remitting MS patients. Further study of vitamin D related mechanisms is warranted in MS.

A randomized trial of intravenous immunoglobulin in inflammatory demyelinating optic neuritis

OBJECTIVE

To determine whether IV immunoglobulin (IVIg) reverses chronic visual impairment in MS patients with optic neuritis (ON).

METHODS

In this double-blind, placebo-controlled Phase II trial, 55 patients with persistent acuity loss after ON were randomized to receive either IVIg 0.4 g/kg daily for 5 days followed by three single infusions monthly for 3 months, or placebo.

RESULTS

The trial was terminated by the National Eye Institute because of negative results when 55 of the planned 60 patients had been enrolled. Fifty-two patients completed the scheduled infusions, and 53 patients completed 12 months of follow-up. Analysis of this data indicated that a difference between treatment groups was not observed for the primary outcome measure, improvement in logMAR visual scores at 6 months (p = 0.766). Exploratory secondary analyses suggested that IVIg treatment was associated with improvement in visual function (including logMAR visual scores at 6 months and visual fields at 6 and 12 months) in patients with clinically stable MS during the trial.

CONCLUSIONS

IVIg administration does not reverse persistent visual loss from ON to a degree that merits general use.

AQP4 autoantibody assay performance in clinical laboratory service

Objective:

To compare performance of contemporary aquaporin-4–immunoglobulin (Ig) G assays in clinical service.

Methods:

Sera from neurologic patients (4 groups) and controls were tested initially by service ELISA (recombinant human aquaporin-4, M1 isoform) and then by cell-based fluorescence assays: fixed (CBA, M1-aquaporin-4, observer-scored) and live (fluorescence-activated cell sorting [FACS], M1 and M23 aquaporin-4 isoforms). Group 1: all Mayo Clinic patients tested from January to May 2012; group 2: consecutive aquaporin-4-IgG–positive patients from September 2011 (Mayo and non-Mayo); group 3: suspected ELISA false-negatives from 2011 to 2013 (physician-reported, high likelihood of neuromyelitis optica spectrum disorders [NMOSDs] clinically); group 4: suspected ELISA false-positives (physician-reported, not NMOSD clinically).

Results:

Group 1 (n = 388): M1-FACS assay performed optimally (areas under the curves: M1 = 0.64; M23 = 0.57 [p = 0.02]). Group 2 (n = 30): NMOSD clinical diagnosis was confirmed by: M23-FACS, 24; M1-FACS, 23; M1-CBA, 20; and M1-ELISA, 18. Six results were suspected false-positive: M23-FACS, 2; M1-ELISA, 2; and M23-FACS, M1-FACS, and M1-CBA, 2. Group 3 (n = 31, suspected M1-ELISA false-negatives): results were positive for 5 sera: M1-FACS, 5; M23-FACS, 3; and M1-CBA, 2. Group 4 (n = 41, suspected M1-ELISA false-positives): all negative except 1 (positive only by M1-CBA). M1/M23-cotransfected cells expressing smaller membrane arrays of aquaporin-4 yielded fewer false- positive FACS results than M23-transfected cells.

Conclusion:

Aquaporin-4-transfected CBAs, particularly M1-FACS, perform optimally in aiding NMOSD serologic diagnosis. High-order arrays of M23-aquaporin-4 may yield false-positive results by binding IgG nonspecifically.

The natural history of multiple sclerosis: a geographically based study: 8: familial multiple sclerosis

We have examined the demographics and long-term outcome of 1044 patients with sporadic and familial multiple sclerosis in a population-based cohort from London, Ontario. The mean follow-up was 25 years in duration, and by this time most patients had reached the unambiguous endpoint scores of the Kurtzke disability status scale (DSS), DSS 6, 8 or 10. An affected family member was identified in 19.8% of the total population, and this subgroup was further divided arbitrarily into the following three groups by the type and number of relatives affected: (i) first degree only; (ii) first degree plus others; (iii) second or third degree. The outcome in these groups was compared with that for those patients who, at a mean 25 year follow-up, had no relatives known to be affected. Familial cases closely resembled those remaining sporadic in both demographics and outcome, although onset in the most heavily loaded families was earlier and male/female ratio was greater. The times to DSS 6, 8 and 10 did not differ significantly when sporadic, familial and familial subgroups were compared. These results provide no clinical support for viewing familial multiple sclerosis as distinct from the sporadic form. The observed recurrence rate for siblings in a strictly defined epidemiological sample was 3.5%, much as projected. These results validate the recurrence risks which have previously been derived from age-corrected data for these first-degree relatives.

A randomized controlled crossover trial of aspirin for fatigue in multiple sclerosis

Pharmacotherapeutic options for multiple sclerosis (MS)-related fatigue are limited. Thirty patients were randomly assigned to aspirin (ASA) 1,300 mg/day or placebo in a double-blind crossover study. Results favored ASA for the main clinical outcomes: Modified Fatigue Impact Scale scores (p = 0.043) and treatment preference (p = 0.012). There were no significant adverse effects. The results warrant further study and support a role for ASA-influenced mechanisms, perhaps immunologic, in the generation of MS-related chronic fatigue.

Genetic variation in the tumor necrosis factor alpha gene and the outcome of multiple sclerosis

The objective of this study was to determine whether sequence variation in the tumor necrosis factor alpha (TNF alpha) gene is associated with MS course and severity in Olmsted County, MN. The severity and temporal course of MS are heterogeneous. Genetic factors may play a role in determining the course of MS. TNF alpha expression is temporally associated with exacerbations of MS and is increased in individuals with progressive disease. The entire TNF alpha gene was amplified by polymerase chain reaction in 78 MS patients and in 39 patients with schizophrenia. Denaturation finger-printing, a modification of direct sequencing that detects virtually all genetic polymorphisms, was performed for four regions spanning the functionally significant portions of the gene, including the promoter region. Polymorphisms were confirmed by complete sequencing. The severity and temporal course of MS were compared in those with wild-type versus variant alleles. Four sequence changes were detected, three of which occurred in MS patients. None occurred in a protein-encoding sequence. Neither of the two most common sequence variants were associated with disease severity or temporal course. Genetic variation of the TNF alpha gene is not associated with variation in the course or long-term outcome of MS in this population-based sample.

A population-based case-control study of the tumor necrosis factor alpha-308 polymorphism in multiple sclerosis

Tumor necrosis factor alpha (TNF alpha) expression is enhanced in patients with active MS and other inflammatory diseases. A guanine-to-adenine polymorphism at position -308 of the TNF alpha promoter region (the TNF2 allele) is associated with increased TNF alpha expression. We evaluated 110 MS patients derived from an Olmsted County, MN, prevalence study. Three other patient cohorts (autoimmune, serious infectious illness, and other neurologic diseases) and matched controls were derived from a Mayo Clinic DNA bank. We used polymerase chain reaction amplification of specific alleles to screen for the TNF2 allele and to determine zygosity. We found one homozygote and 29 heterozygotes in the MS patients. There was no association between the presence of the TNF2 allele and MS or the other disease categories by matched-pair and group analyses.

Clinical outcome measures and rating scales in multiple sclerosis trials

In this review, we analyzed clinical outcome measures used in multiple sclerosis (MS) clinical trials in which the primary goal is to slow or arrest progression of disease. In addition, we examined rating scales that quantify symptomatic complications of MS (for example, spasticity) and the current role of magnetic resonance imaging in MS treatment trials. Each proposed scale has advantages and deficiencies, and none meets all the criteria for an ideal outcome measure. The validity of trial design may be improved by using combinations of selected components of current scales as well as new instruments targeted to specific variables (such as motor strength). Symptom-specific rating scales are most appropriately used in trials of symptomatic therapeutic strategies for MS. Until serial magnetic resonance imaging changes are definitely known to predict long-term impairment and disability in patients with MS, clinical outcome measures will remain the primary means of assessing therapeutic efficacy in phase III clinical trials.

Is there a neurologist on this flight?

OBJECTIVE

To analyze the frequency of neurologic events during commercial airline flights and to assess whether onboard emergency medical kits are adequate for in-flight neurologic emergencies.

METHODS

Collaboration of the Mayo Clinic's Departments of Emergency Medicine and Medical Transportation Service and the Division of Aerospace Medicine to provide real-time in-flight consultation to a major US airline that flies approximately 10% of all US passengers. We analyzed all medical events reported from 1995 to 2000 in a database that catalogs the air-to-ground medical consultations. All cases with potential neurologic symptoms were reviewed and classified into various neurologic symptom categories. The cost of diversion for each neurologic symptom was calculated and then extrapolated to assess the cost of neurologic symptoms to the US airline industry.

RESULTS

A total of 2,042 medical incidents led to 312 diversions. Neurologic symptoms were the single largest category of medical incidents, prompting 626 air-to-ground medical calls (31%). They caused 34% of all diversions. Dizziness/vertigo was the most common neurologic symptom followed by seizures, headaches, pain, and cerebrovascular symptoms. Whereas seizures and dizziness/vertigo were the most common reasons for diversion, loss of consciousness/syncope was the complaint most likely to lead to a diversion. The estimated annual cost of diversions due to neurologic events is almost 9,000,000 dollars.

CONCLUSION

Neurologic symptoms are the most common medical complaint requiring air-to-ground medical support and are second only to cardiovascular problems for emergency diversions and their resultant costs to the US airline industry. Adding antiepileptic drugs to the onboard medical kit and greater emergency medical training for in-flight personnel could potentially reduce the number of diversions for in-flight neurologic incidents.

Early versus late antiepileptic drug withdrawal for people with epilepsy in remission

BACKGROUND

Antiepileptic drugs ( AEDs) are used to prevent seizures but are associated with both short and long term adverse effects. When epilepsy is in remission, it may be in the patient's best interest to discontinue medication. However, the optimal timing of AED discontinuation is not known.

OBJECTIVES

To quantify seizure relapse risk after early (less than two seizure free years) versus late (more than two seizure free years) AED withdrawal in adult and pediatric epilepsy patients. To assess which variables modify the risk of seizure recurrence.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trials register, the Cochrane Controlled trials register (Cochrane Library Issue 4, 2000), MEDLINE (January 1996 to January 2001), EMBASE, Index Medicus, CINAHL, as well as hand-searching of journals.

SELECTION CRITERIA

Randomized controlled trials that evaluate withdrawal of AEDs after varying periods of seizure remission in adult and pediatric epilepsy patients with or without blinding were included. Included studies compared an early versus late AED discontinuation.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality. Relative risks with 95% confidence intervals were calculated for each trial. Summary relative risks and 95% confidence intervals for dichotomous data were calculated using a random effects model. A test of statistical heterogeneity was conducted for each pooled relative risk calculation.

MAIN RESULTS

Seven eligible controlled trials were included in the analysis representing 924 randomized pediatric patients. There were no eligible trials evaluating adult seizure free patients. The pooled relative risk for seizure relapse in early versus late AED withdrawal was 1.32 (95% confidence interval 1.02 to 1.70). On the basis of this estimate, the number needed to harm, that is expose an individual to a higher risk of seizure relapse because of early withdrawal of AED, is 10. Early discontinuation was associated with greater relapse rates in patients with partial seizures[pooled RR = 1.52; 95% confidence interval 0.95 to 2.41] or an abnormal EEG [pooled RR=1.67; 95% confidence interval 0.93 to 3.00].

REVIEWER'S CONCLUSIONS

There is evidence to support waiting for at least two or more seizure free years before discontinuing AEDs in children, particularly if individuals have an abnormal EEG and partial seizures. There is insufficient evidence to establish when to withdraw AEDs in pediatric patients with generalized seizures. There is no evidence to guide the timing of withdrawal of AEDs in adult seizure free patients. Further blinded randomized controlled trials are needed to identify the optimal timing of AED withdrawal and risk factors predictive of relapse.

The effects of monoamine oxidase B inhibition on dopamine metabolism in rats with nigro-striatal lesions

The purpose of this study was to examine whether monoamine oxidase type B (MAO-B) has a role in striatal dopamine metabolism in animals with a unilateral lesion of the medial forebrain bundle, and whether 2-phenylethylamine (PE) could have a role in amplification of dopamine (DA) responses in DA depleted striatum. Inhibition of MAO-B did not alter DA metabolism in lesioned striata. PE accumulation decreased with loss of DA as long as there was no DA dysfunction. In lesioned striata with dysfunction of DA transmission at the synaptic level, PE accumulation increased, suggesting a compensatory increase in PE synthesis. This increase in PE levels does not appear to be mediated by an increase in the total striatal aromatic L-amino acid decarboxylase (AADC) activity. We conclude that inhibition of MAO-B has no effect on DA metabolism in the hemi-parkinsonian rat striatum and that PE could be involved in the antiparkinsonian action of MAO-B inhibitors.

Cerebral venous thrombosis complicated by hemorrhagic infarction: factors affecting the initiation and safety of anticoagulation

BACKGROUND AND PURPOSE

Anticoagulation (AC) may improve outcome in cerebral venous thrombosis (CVT), even when complicated by pretreatment hemorrhagic infarction (HI). The HI characteristics which affect the decision to initiate AC therapy and its outcome are unknown. We reviewed our experience with AC treatment for patients with CVT and HI.

METHODS

Retrospective study.

RESULTS

Two groups of patients were compared: those who received AC (n = 6) and those who did not (n = 6). Hemorrhage volumes ranged from petechial to large (93 cm3) hematoma with mass effect. Anticoagulated patients received treatment a mean of 11.3 days after symptom onset. Each had exclusively extratemporal HI without midline shift and had stable hemorrhage volumes and clinical status for at least 24 h prior to AC. AC did not increase HI volume or worsen clinical outcome. All 6 non-AC patients had enlarging hematomas. Four of these 6 patients had temporal HI; and two required hematoma resection.

CONCLUSIONS

AC therapy was avoided in CVT patients with HI that were located in the temporal lobe, caused midline shift or were enlarging. AC was safely initiated within several days in clinically stable patients with non-temporal-lobe HI of unchanging volume. We suggest that the location and unchanged volume on serial CT may be important factors influencing the safety of AC therapy in patients with CVT and HI.

Genetic variants in the tumor necrosis factor receptor 1 gene in patients with MS

We scanned for all genetic variants in functionally important regions of the tumor necrosis factor receptor 1 gene (TNF-R1) in 100 to 111 MS patients from Olmsted County, MN, and analyzed selected variants for an association with disease course and severity. Ten genetic variants were uncovered. Only one variant, a silent substitution, was found in coding sequence. One intronic variant may generate a novel splice-junction sequence. We did not find an association between either this intronic variant or another common promoter variant and the course or severity of MS.

The natural history of multiple sclerosis: implications for trial design

The understanding of the natural history of multiple sclerosis has many implications for the design and interpretation of randomized controlled trials. Selection criteria, patient stratification, outcome measurements, and definitions of treatment failure can influence randomized controlled trial results and limit comparisons among trials. The focus of future studies should shift from short-term determinations of efficacy to definitive evaluations of long-term effectiveness. This will require novel investigative strategies such as the use of historic controls derived from natural history studies.

Paraneoplastic encephalomyelitis and seminoma: importance of testicular ultrasonography

We report two patients with paraneoplastic limbic and brainstem encephalitis associated with occult nonmetastatic testicular seminoma. In each patient, the neoplasm was detectable only by testicular ultrasonography. Male patients with this syndrome in whom lung cancer is not found should undergo testicular ultrasonography as part of the search for an extrapulmonary neoplasm. A normal clinical testicular examination is insufficient to exclude an occult seminoma.

Multifocal brain MRI artifacts secondary to embolic metal fragments

We report a patient with unusual MRI abnormalities that had the physical characteristics of ferromagnetic artifact. We believe that the MRI artifacts were due to microscopic embolic metal fragments, most likely from a mechanical heart valve prosthesis. Potential sources of metal emboli should be considered in patients with MRI abnormalities compatible with ferromagnetic artifact.