Neurological complications of excessive recreational nitrous oxide use: a case series based on a text mining algorithm.

BACKGROUND: The recreational use of nitrous oxide (N2O) has gained popularity over recent years. We present a case series of excessive N2O users with neurological complications. METHODS: In this retrospective three-centre study, we used a text mining algorithm to search for patients who used N2O recreationally and visited a neurologist. RESULTS: We identified 251 patients. The median duration of N2O use was 11 months (interquartile range [IQR], 3-24) and the median amount of N2O used per occasion 1.6 kg (IQR 0.5-4.0). Clinically, polyneuropathy (78%), myelopathy (41%), and encephalopathy (14%) were the most common diagnoses. An absolute vitamin B12 deficiency of < 150 pmol/L was found in 40% of cases. In 90%, at least one indicator of functional vitamin B12 status (vitamin B12, homocysteine, or methylmalonic acid) was abnormal. MRI showed signs of myelopathy in 30/55 (55%) of cases. In 28/44 (64%) of those who underwent electromyography, evidence of axonal polyneuropathy was found. Most (83%) patients were treated with vitamin B12 supplementation, and 23% were admitted to the hospital. Only 41% had follow-up for ≥ 30 days, and 79% of those showed partial or complete recovery. CONCLUSIONS: In this case series of excessive N2O users, we describe a high prevalence of polyneuropathy, myelopathy, and encephalopathy. Stepwise testing for serum levels of vitamin B12, homocysteine, and methylmalonic acid may support the clinical diagnosis. Due to low sensitivity, MRI of the spinal cord and electromyography have limited value. Effective treatment should incorporate supplementation of vitamin B12 and strategies to prevent relapses in N2O use.

Presentation outside office hours does not negatively influence treatment times for reperfusion therapy for acute ischemic stroke.

BACKGROUND: Treatment outside office hours has been associated with increased workflow times for intravenous thrombolysis (IVT) in acute ischemic stroke (AIS). Limited data suggest that this "off-hours effect" also exists for endovascular treatment (EVT). We investigated this phenomenon in a well-organized acute stroke care region in the Netherlands. METHODS: Retrospective, observational cohort study of consecutive patients with AIS who received reperfusion therapy in the Greater Amsterdam Area, consisting of 14 primary stroke centers and 1 comprehensive stroke center (IVT: 2009-2015, EVT: 2014-2017). Office hours were defined as presentation during weekdays between 8 AM and 5 PM, excluding National Festive days. Primary outcome was door-to-treatment time (door-to-needle [DNT] for IVT, door-to-groin [DGT] for EVT). For DGT, we used the door time of the first hospital. Other outcomes were in-hospital mortality, modified Rankin Scale (mRS) score at 90 days and symptomatic intracranial hemorrhage (sICH). We performed multivariable linear and logistic regression analyses and used multiple imputation to account for missing values. RESULTS: In total, 59% (2450/4161) and 61% (239/395) of patients treated with IVT and EVT, respectively, presented outside office hours. Median DNT was minimally longer outside office hours (32 vs. 30 min, p = 0.024, adjusted difference 2.5 min, 95% CI 0.7-4.2). Presentation outside office hours was not associated with a longer DGT (median 130 min for both groups, adjusted difference 7.0 min, 95% CI - 4.2 to 18.1). Clinical outcome and sICH rate also did not differ. CONCLUSION: Presentation outside office hours did not lead to clinically relevant treatment delays for reperfusion therapy in patients with AIS.

Screening and patient-tailored care for emotional and cognitive problems compared to care as usual in patients discharged home after ischemic stroke (ECO-stroke): a protocol for a multicenter, patient-blinded, cluster randomized controlled trial.

BACKGROUND: Ischemic stroke patients with a good outcome in terms of motor functioning and communication are likely to be discharged home without further rehabilitation. A significant number of these patients experience cognitive and emotional problems resulting in lower quality of life and decreased participation in society. This paper presents the protocol of a study examining the clinical effectiveness, cost-effectiveness and implementation of an intervention focused on screening and patient-tailored care for cognitive and emotional problems as compared to usual care in patients discharged home after ischemic stroke. METHODS / DESIGN: A multicenter, patient-blinded, cluster randomized controlled trial will be performed. Centers will be randomized (1:1) to the intervention group or the usual care group. Patients (> 18 years old) with a neurological confirmed diagnosis of ischemic stroke who can be discharged home without follow-up treatment at an outpatient rehabilitation clinic will be included. In the intervention group, patients will receive a short, individualized, semi-structured consultation by specialized nurses in addition to usual care. This consultation includes 1) screening for cognitive and emotional problems, 2) screening for restrictions in participation, 3) promotion of self-management strategies and 4) a decision tool for referral to rehabilitation services. The intervention will be performed approximately 6 weeks after the stroke at the neurology outpatient clinics and will take approximately 60 min. The control group will receive care as usual. Both groups will be followed-up at 6 weeks, 3 months and 12 months after stroke. The primary outcome will be the level of participation measured with the Restriction subscale of the Utrecht Scale for Evaluation of Rehabilitation on the level of Participation (USER-Participation-R) at 12 months. A cost-effectiveness analysis and process evaluation will be performed alongside. DISCUSSION: This trial is the first to evaluate clinical effectiveness, cost-effectiveness and implementation of screening and patient-tailored care for cognitive and emotional problems compared to care as usual in patients discharged home after ischemic stroke. Potentially, this will improve the outcomes for patients with frequently occurring cognitive and emotional problems after stroke. TRIAL REGISTRATION: Netherlands Trial Register: NL7295 , registered 25 September 2018.

['Histrionic personality disorder with regression and conversion': a meningioma]. / 'Theatrale persoonlijkheidsstoornis met regressie en conversie'; een meningeoom.

A 47-year-old woman, who was believed to be suffering from histrionic personality disorder with regression and conversion, was finally diagnosed with a frontal meningioma. Patients with meningiomas can present with a variety of psychiatric symptoms, sometimes even before neurological symptoms occur. The diagnosis is often delayed because the symptoms are misleading and it is difficult to modify a psychiatric diagnosis once this has been made. Discussion focuses on the characteristic signs of a meningioma, the reasons for delays in diagnosis and the indications for brain-imaging on psychiatric patients.

Retinal arterial changes correlate with cerebral small-vessel disease.

OBJECTIVE: To examine the relation between retinal artery disease and cerebral small-vessel disease (SVD). METHODS: In a prospective cohort of patients with symptomatic atherosclerotic disease, the authors performed retinal photographs and brain MRI. Two ophthalmologists, not aware of the MR results, independently assessed retinal arterial narrowing, crossings, sclerosis, and tortuosity according to standard scoring lists. Two observers independently assessed white matter lesions (WML) and lacunar infarcts on the MR images. Lesions were considered abnormal only when both ophthalmologists or MR raters agreed. Cerebral SVD was defined as the presence of WML or lacunar infarcts. RESULTS: In 179 patients, retinal photographs and brain MRI were performed. Of the 108 patients with MR signs of SVD, 92% had at least one retinal vascular abnormality; of the 71 patients without SVD, 77% had retinal pathology (p < 0.01). All types of retinal vascular pathology occurred more frequently in patients with SVD, but only retinal arterial narrowing and sclerosis differed significantly. In the 109 normotensive patients, the presence of any retinal vascular change correlated with signs of SVD (p = 0.01). CONCLUSION: Pathologic changes in the retinal arteries parallel changes in the small cerebral arteries that cause WML and lacunes, both in hypertensive and in normotensive patients.

Determinants of quantitative spectral electroencephalography in early Alzheimer's disease: cognitive function, regional cerebral blood flow, and computed tomography.

Electroencephalography (EEG) bands may have different clinical or physiological correlates at initial diagnosis of Alzheimer's disease (AD). We studied 163 consecutive patients with probable (n = 105) and possible (n = 58) AD with measurements of cognitive function (CAMCOG), regional cerebral blood flow (rCBF) with single photon emission computed tomography using technetium-99m-labeled hexamethylpropylene amine oxime, and computed tomography (CT). Lower CAMCOG scores were significantly and most strongly associated with lower parieto-occipital and fronto-central alpha power. In a separate analysis of cognitive domains, disturbances in language, praxis, attention, and abstraction were also significantly and most consistently related to decrease in alpha power. Presence of cortical atrophy as measured on CT showed some statistically significant relations with EEG bands, but these associations were not consistent. Lower temporal and parietal rCBF were significantly related to lower parieto-occipital alpha activity. Presence of leukoaraiosis was significantly associated with lower beta values, but also with higher absolute theta and delta activity. The results suggest that alpha on EEG is most closely linked to cognitive function and rCBF, while beta and theta activity more likely reflect lower cortical or subcortical changes. Our study thus provides evidence that the EEG bands reflect differential pathophysiologic changes in AD.

Arteriovenous and lymphatic malformations, linear verrucous epidermal nevus and mild overgrowth: another hamartoneoplastic syndrome?

We report a 22 year old female presenting with slowly progressive paraparesis, who appeared to have many (mainly subcutaneous) hamartomas. The neurological symptoms were caused by intraspinal masses and arteriovenous malformations. In addition, she had mild overgrowth of one leg and lymph vessel malformations. This combination of symptoms resembles Proteus syndrome, but is different in symptomatology and progression and may be yet another hamartoneoplastic syndrome.

Slowing on quantitative spectral EEG is a marker for rate of subsequent cognitive and functional decline in early Alzheimer disease.

The relation between quantitative spectral electroencephalogram (qEEG) parameters and subsequent rate of cognitive, functional, and behavioral decline in 82 consecutive patients with early probable Alzheimer disease (NINCDS-ADRDA criteria) was examined in a prospective study. The qEEG was performed at initial examination and global cognitive function, activities of daily living, and behavior were assessed at initial evaluation and after a period of 6 months. Using multiple linear regression analysis, higher frontocentral and parieto-occipital theta values, lower parieto-occipital beta values, and lower peak frequency were significantly associated with more decline in global cognitive function over the follow-up period. In addition, lower parieto-occipital beta values were significantly related to more decline in activities of daily living. These associations were independent of demographic (age, sex, and education) and disease characteristics [initial Cambridge Examination for Mental Disorders of the Elderly Cognitive test (CAMCOG) or Mini-Mental State Examination scores, estimated duration of symptoms, estimated prior rate of decline, and dementia severity]. In a separate multiple logistic regression analysis, prediction of rapidly progressive decline, defined as 8 or more points decline in CAMCOG scores (n = 21), could be made with parieto-occipital and frontocentral beta values. The results suggest that slowing on qEEG is a marker for subsequent rate of cognitive and functional decline in mildly demented AD patients, independent of demographic or disease characteristics.

Silent intracerebral microhemorrhages in patients with ischemic stroke. Amsterdam Vascular Medicine Group.

We compared the frequencies of signs of old intracerebral hemorrhages on brain magnetic resonance imaging scans in 66 patients with ischemic stroke, 69 with myocardial infarction, and 86 with peripheral arterial disease (a total of 221 patients). Magnetic resonance imaging scans were independently assessed by two investigators without knowledge of clinical or laboratory data. In 31 patients (14%) we found local cerebral hemosiderin deposits. In 24 patients they were clinically silent. Hemosiderin deposits were significantly more frequent in patients with ischemic stroke (26%) than in patients with myocardial infarction (4%) or peripheral arterial disease (13%). Hemosiderin deposits were associated with cerebral white matter lesions (odds ratio, 5.3; 95% confidence interval, 2.5-12.4). The odds ratios were higher in patients with severe cerebral white matter lesions. Our findings support the hypothesis that cerebral vessels of patients with ischemic stroke are more prone to rupture than those of patients with other manifestations of atherosclerotic disease, which may explain the higher incidence of intracerebral hemorrhages when these patients are treated with oral anticoagulants. The microhemorrhages were associated with cerebral white matter lesions, which suggests that they are another manifestation of cerebral small-vessel disease.

Predicting survival in patients with early Alzheimer's disease.

We investigated whether an index based on clinical features, electroencephalogram and computed tomography is useful to predict survival in early Alzheimer's disease. One hundred and sixty-three consecutively referred patients to an outpatient memory clinic and first diagnosed with Alzheimer's disease (105 'probable' and 58 'possible', NINCDS-ADRDA criteria) were studied and outcome measure was death. Cox proportional hazards regression analysis and Kaplan-Meier survival curves were used to investigate relations between baseline parameters and survival. Eighty-four patients (51. 5%) died during the follow-up period that extended to 5.8 years, with a median duration of survival after entry of 4.3 years. Baseline factors that were statistically significant and independently related to increased risk of mortality were high age, male sex, poor cognitive function as measured with the CAMCOG, low alpha and beta power on electroencephalogram, and temporoparietal atrophy on computed tomography scan. These results were independent of the diagnosis probable or possible Alzheimer's disease. Based on the coefficients from the regression equation, we computed a survival index for each patient and we constructed three groups according to tertiles of this index. After 5.2 years of follow-up, survival curves showed a low mortality group with 81.7% patients alive (median survival at least 5.7 years), an intermediate mortality group with 35.9% patients alive (median survival 3.8 years), and a high mortality group with no patients alive (median survival 2.3 years). Log rank tests were statistically significant for comparisons between all three groups. We conclude that an overall index combining demographic, cognitive, electroencephalogram and computed tomography features is a strong predictor of survival in early Alzheimer's disease.

Disequilibrium in patients with atherosclerosis: relevance of pontine ischemic rarefaction. Amsterdam Vascular Medicine Group.

OBJECTIVE: To examine the clinical relevance of isolated pontine hyperintense lesions (PHLs) on MRI in patients with atherosclerosis. METHODS: Seventeen atherosclerotic patients with isolated PHL on MRI were compared with 17 patients without PHL and were matched for age, sex, and initial manifestation of atherosclerosis. Subjects and observer were blinded to the MRI findings. We assessed symptoms, impairment, and disability with a structured interview and neurologic examination as well as disability scales. RESULTS: On all items, patients with PHL scored worse than did their controls. We found the largest differences in frequencies of symptoms of disequilibrium, difficulties with speech or swallowing, the Timed Walking Test, and the body care and movement subscale of the Sickness Impact Profile. Except for disequilibrium (p = 0.04), these differences did not reach statistical significance. Abnormal tandem-walking tests were more frequent in patients than they were in controls. Pyramidal signs were equally distributed. CONCLUSIONS: We propose PHL as a cause of symptoms of disequilibrium in patients with atherosclerosis. Symptoms are probably elicited by dysfunction of the corticopontine fibers, the pontocerebellar fibers, or the pontine nuclei.

T2-weighted hyperintense MRI lesions in the pons in patients with atherosclerosis. Amsterdam Vascular Medicine Group.

BACKGROUND AND PURPOSE: Pontine hyperintense lesions (PHL) on T2-weighted MRI have been recognized recently. Histopathological findings resemble periventricular leukoaraiosis, and a vascular etiology has been suggested. We studied the frequency and the associated factors of PHL in patients with symptomatic atherosclerosis. METHODS: Two independent observers assessed brain MRIs in a prospective cohort of patients with symptomatic atherosclerosis. Only patients in whom both observers scored PHL on T2- and proton density-weighted images, but not on T1-weighted images, were considered to have the lesion. RESULTS: We studied 229 patients 31% presenting with ischemic stroke, 31% with myocardial infarction, and 38% with peripheral artery disease. Both observers scored PHL in 23% of all patients. Patients with PHL were significantly older and had more lacunar infarcts and periventricular leukoaraiosis than patients without PHL. There were more women, more hypercholesterolemic and diabetic patients, and more cortical infarcts on MRI (P = NS). After logistic regression the presence of leukoaraiosis (odds ratio, 2.4; 95% confidence interval, 1.6 to 3.4) and lacunar infarcts (odds ratio, 2.2, 95% confidence interval, 1.5 to 3.1) remained independently associated with PHL. PHL was more common in patients with ischemic strokes (39%) than in patients with myocardial infarctions (11%) or peripheral artery disease (19%) (P < .001). CONCLUSIONS: We found that PHL on T2- and proton density-weighted MR images are often found in patients with symptomatic atherosclerosis. The association with periventricular leukoaraiosis and lacunar infarcts suggests that PHL is a variant of leukoaraiosis, with possibly the same pathophysiology. The clinical symptoms and consequences of PHL, however, are not yet clear.

The role of cognitive impairment in the quality of life after ischaemic stroke.

Many patient- and disease-related factors influence the quality of life (QL) after stroke. Few studies address the direct relation between cognition and quality of life. The objective of this study was to investigate the role of cognitive impairment in the QL of patients after stroke. We evaluated several variables including age, degree of paralysis, cognitive deficits and volume of infarcts, in 129 patients (64 men, 65 women; mean age 63.2, SD 14.6 years), who had been hospitalized a mean of 2.3 (range 0.25-4) years previously with ischaemic stroke. Cognitive function was assessed with the CAMCOG and QL with a visual analogue scale (VAS). Ninety-seven patients (75%) of our sample completed all the tests. Univariate analysis showed that substantial infarct volume, aphasia, impaired motor function, disability relating to activities of daily life, disturbed global functional health and impaired cognitive function were significantly associated with poorer QL. Age, sex and education of the patient, co-morbidity and location of the infarcts were not related to QL. Linear regression analysis revealed that disturbed global functional health, larger volume of infarcts and severity of aphasia were significant independent explanatory factors for poorer QL (adjusted R2 = 22%). In conclusion, we did not find a significant impact of cognitive impairment on the patients' QL. However, this conclusion is restricted to a relatively well group of stroke survivors.

Feasibility of cognitive screening of patients with ischaemic stroke using the CAMCOG. A hospital-based study.

Brief screening tests would be convenient for the measurement of cognitive impairment in stroke patients. In these patients aphasia can interfere with test procedures. To evaluate the feasibility of examining cognitive functions in stroke patients we examined 129 patients with an ischaemic stroke using the CAMCOG, a standardised neuropsychological screening test, after an interval of at least 3 months. Most patients (88%) were able to complete the CAMCOG. Patients with severe aphasia were significantly more likely to have an abnormal CAMCOG score than patients without aphasia [relative risk (RR) 4.0, 95% confidence interval (CI) 2.8-5.8]. The group of patients with moderate aphasia was not at higher risk of having an abnormal CAMCOG score than patients without aphasia (RR 1.4, 95% CI 0.6-2.8). Looking for other factors that might correlate with the scores, logistic regression analysis revealed age as the only significant factor for the prediction of the CAMCOG score (odds ratio 4.0, 95% CI 1.2-13.2). We concluded that the CAMCOG can conveniently be used for screening cognitive functions in patients with cerebral infarcts, even if there is moderate aphasia.

Epidermal nevus syndrome with isolated enlargement of one temporal lobe: a case report.

A 5-month-old girl presented with infantile spasms and psychomotor retardation. She was born with epidermal nevi on the right side of the head, the right arm and the back. MRI of the head showed a right hemimegalencephaly limited to the temporal lobe. There were no MRI signs of neocortical dysplasia. Ultrasonography revealed multiple cysts in both ovaria and a small solid lesion in the left adrenal gland. Hemimegalencephaly represents an overgrowth phenomenon; the isolated temporal lobe hypertrophy can be explained as a mild expression of hemimegalencephaly. To our knowledge this has not been described before.

Spectral analysis of the EEG and 99m-Tc-HMPAO SPECT-scan in Alzheimer's disease.

99m-technetium-hexamethylpropylene-amineoxine (99m-Tc-HMPAO) single-photon-emission-computer-tomography (SPECT)-scans and spectral analyzed electroencephalogram (EEGs) of 20 patients with Alzheimer's disease (AD) were studied. A significant correlation was found between the temporoparietal-cerebellar-ratio (TP/C-ratio) of the SPECT-scan and the peak frequencies of leads T3-T5, C3-P3, and C4-P4 of the EEG. In addition a significant negative correlation between the TP/C-ratio and the theta/alpha-ratio (t/a-ratio) of leads T3-T5, T4-T6, C3-P3, and C4-P4 was demonstrated. Our study demonstrates that slowing of the EEG parallels a decrease in blood flow in the temporoparietal regions in AD-patients. Both findings could be parallel phenomena of regional hypometabolism.