Weather conditions and transient global amnesia. A six-year study.

OBJECTIVES: The aetiology of transient global amnesia (TGA) is still unknown. Various events or activities have been shown to trigger TGA. A common feature of these events is an increased sympathetic activity which in turn may be influenced by meteorological factors. This prompted us to evaluate the influence of climatic parameters, and their variation on the incidence of TGA. METHODS: A total of 223 cases of TGA admitted to our hospital over a six-year period were studied. The study consisted of a comparison between the climatic parameters of days with TGA and those without TGA. The meteorological database included daily values of parameters recorded at the meteorological station of the town during this period. RESULTS: The onset of TGA was significantly correlated with lower daily,monthly and seasonal temperature values. Most cases of TGA were found when the temperature was less than 6.9 degrees C,whereas the frequency of TGA was minimum when it was more than 24 degrees C (P < 0.0001). Only temperature had a significant independent effect: an increase of 1 sd = 8.4 degrees C decreases the TGA admission odds of 0.78 (95 % CI: 0.62 to 0.97), i.e -22% (95 % CI: -38% to -3 %). CONCLUSIONS: This study suggests an association between TGA occurrence and low ambient temperature. Multicentre studies taking into account climatic differences between countries are necessary to confirm our findings.

Combined 99mTc-ECD SPECT and neuropsychological studies in MCI for the assessment of conversion to AD.

Identifying pre-clinical Alzheimer's disease (AD) in subjects with mild cognitive impairment (MCI) is a major issue in clinical diagnosis. Establishing a combination of predictive markers from different fields of research might help in increasing the diagnostic accuracy. Aim of this study was to evaluate the potential role of 99mTc-ECD single photon emission computed tomography (SPECT) and memory scores in predicting conversion to AD in MCI subjects. Thirty-one MCI subjects underwent a clinical and neuropsychological examination, and a regional cerebral blood flow (rCBF) SPECT scan at baseline. Subjects had been followed periodically through 2 years in order to monitor the progression of cognitive symptoms. Canonical variate analysis of principal components was able to separate all subjects who converted to AD from those who remained stable, the former being characterized by a specific hypometabolic pattern, involving the parietal and temporal lobes, precuneus, and posterior cingulate cortex. Canonical correlation analysis of combined baseline memory deficits and rCBF SPECT images identified pre-clinical AD with a sensitivity and specificity of 77.8%. The pattern of hypoperfusion 99mTc-ECD SPECT and the severity of memory deficits predict the risk of progression to probable AD dementia in MCI subjects.

Volume reduction in cerebral blood flow in patients with Alzheimer's disease: a sonographic study.

Neuroimaging techniques such as PET and SPECT demonstrated a consistent reduction of cerebral blood flow (CBF) in Alzheimer's disease (AD). The aim of the study was to assess the potential role of ultrasonography for CBF measurement in AD patients and whether the CBF volume correlates positively with disease severity. Fifty patients who met the diagnostic criteria of probable AD (NINDS-ADRDA) were compared to 50 age-matched healthy elderly volunteers. The extracranial internal carotid arteries (ICAs) and the vertebral arteries (VAs) of the patients and controls were examined. Angle-corrected time-averaged flow velocity (TAV) and the diameter of the vessel were measured. Intravascular flow volumes were calculated as the product of TAV and the cross-sectional area of the circular vessel. CBF volume was calculated as the sum of flow volumes in the ICAs and VAs of both sides. All subjects underwent the MMSE. The mean global CBF (474.87 +/- 94.085 vs. 744.26 +/- 94.082 ml/min; p < 0.0001) was lower in AD patients than in healthy volunteers. A significant decline in global flow volumes (r = 0.48; p < 0.0007) with the degree of cognitive impairment was also present. The ability of ultrasonography to characterize flow decreases makes such a technique an attractive tool for the study of AD, for the evaluation of pharmacological therapies and, possibly, for early diagnosis.

Crossed aphasia with left spatial neglect and visual imperception: a case report.

A 64-year-old right-handed woman with no left-handers in the family developed aphasia associated with moderate left hemiparesis and dense left homonymous hemianopia following rupture of a right middle cerebral artery aneurysm and subsequent selective surgery confined to the right hemisphere. Severe left spatial neglect and constructional apraxia were also present. The patient was an achondroplasic dwarf whose previous medical and neurological history was otherwise unremarkable. Computed tomography of the brain showed a large right temporo-insulofrontoparietal lesion. Language and nonverbal cognitive functions were assessed after 2 and 6 months, and then four years later. A reportedly overall language disruption in the acute period evolved into Wernicke's aphasia and then into a mild form of conduction aphasia. The associated left spatial neglect eventually shrank to a minimum. The patient never had clinically detectable visual agnosia, but on specific tests of visual recognition and perception some impairment was found four years after onset. The left hemiparesis disappeared in time while the left hemianopia persisted. This case is a convincing example of an entirely righthanded person in whom both linguistic and visuospatial functions are represented in the right hemisphere.

Transient global amnesia: a clinical and sonographic study.

BACKGROUND: The aetiology of transient global amnesia (TGA) is still unknown. The aim of this study was to identify potential risk factors for TGA, vascular risk factors, the role of patent foramen ovale (PFO) and of retrograde jugular venous flow. METHODS: 138 subjects entered the study, including 48 patients with TGA, 42 age-matched patients with transient ischaemic attack (TIA) and 48 controls. PFO was studied by contrast transcranial duplex sonography. Retrograde jugular venous flow was tested with air contrast ultrasound venography (ACUV). RESULTS: TGA patients and controls showed a lower prevalence for vascular risk factors than TIA patients. No statistical difference was found between the 3 groups with regard to PFO. ACUV detected jugular valve incompetence in 72.9% TGA, 35.7% TIA and 39.5% controls (TGA vs. TIA and TGA vs. controls p < 0.01). CONCLUSIONS: TGA patients have fewer vascular risk factors than TIA patients. Paradoxical embolism due to PFO as a cause of TGA is not confirmed in our study. Cerebral venous hypertension due to incompetence of the internal jugular valve may play a role in the pathogenesis of TGA.

Prevalence and pattern of cognitive impairment in systemic lupus erythematosus patients with and without overt neuropsychiatric manifestations.

The prevalence and pattern of cognitive impairment in systemic lupus erythematosus (SLE) patients with (NPSLE) and without (nSLE) overt neuropsychiatric manifestations were investigated. Fifty-two nSLE patients, 23 NPSLE patients and 27 healthy controls were evaluated with a battery of standardized neuropsychological and psychological tests. Disease duration, disease activity index, and current corticosteroid therapy were collected. Cognitive impairment was identified in 14 (26.9%) and in 12 (52.2%) of subjects with nSLE and NPSLE, respectively. Both SLE groups showed a significant impairment compared with controls on tasks assessing verbal and non-verbal long-term memory, and visuoconstructional abilities. In addition, NPSLE patients reported worse performances than both nSLE patients and controls on task evaluating short-term visuospatial memory. NPSLE subjects were significantly more anxious and depressed compared to both nSLE subjects and controls. By multivariate analysis, only depression levels, among clinical variables, significantly predicted cognitive performance. This study shows that cognitive impairment occurs frequently in both nSLE and NPSLE subjects. The higher frequency in NPSLE may be related to coexisting depressive disturbances.

Lemierre's syndrome complicated by carotid thrombosis.

Lemierre's syndrome, also known as postanginal sepsis, is a rare condition that presents as an increasing sore throat due to acute pharyngitis or tonsillitis and progresses to sepsis, due to suppurative thrombophlebitis of the internal jugular vein. We present an atypical case of Lemierre's syndrome complicated by carotid thrombosis. The etiological factors and the diagnostic and therapeutic measures are discussed.

The many faces of crossed aphasia in dextrals: report of nine cases and review of the literature.

A substantial body of the aphasia literature has been devoted to the topic of crossed aphasia in dextrals (CAD) over the past century but still no theory exists that explains the anomalous organization of neurocognitive functions in this population. However, if strict selection criteria are applied only some cases of vascular CAD are reported in which the correlation between neurocognitive disturbances and the locus of the brain lesion is studied. This study describes nine new cases of vascular CAD who underwent in-depth neurolinguistic and neuropsychological investigations. Our analysis shows the semiological variability of CAD phenomena and the many faces of the lesion-behaviour relationships of this exceptional neurobiological condition.

[Approach to the patient in vegetative state. Part II: differential diagnosis]. / Approccio al paziente in stato vegetativo. Parte II: La diagnosi differenziale.

A prerequisite to the diagnosis of vegetative state is the exclusion of apparently similar syndromes, in which the patient retains the consciousness partially or even completely. Some syndromes are not separate nosological entities and should be abandoned: the apallic state, the neocortical death, the decerebrate and decorticate state, the alpha-coma, the vigil or prolonged or irreversible coma are among them. Three conditions deserve special consideration. The term locked-in syndrome describes a patient completely paralysed and mute, but fully conscious, and is usually caused by ischemic lesions of the pons. Several variants do exist, either in the causes and site of lesion. Some patients may become paralysed and mute, but conscious because of polyneuropathies, that is in the absence of any lesions of the central nervous system. The akinetic mutism is a rare condition characterised by loss of speech and nearly absent bodily movements. Painful stimulation may cause appropriate withdrawing, and wakefulness and self-awareness may be preserved, but cognitive impairment is usually present. It must be emphasised that this condition can be due to potentially treatable lesions, such as hydrocephalus and craniopharyngioma. The term "minimally responsive" or "minimally conscious" describes severely disabled patients in whom meaningful responses can be demonstrated, although inconstantly. This condition, the true diagnostic challenge, often represents a transition phase of vegetative patients recovering consciousness. Physicians, physiotherapists and patient's relatives should work all together to reach a correct diagnosis, by using current available methods to monitorize the recovery of consciousness.

Confabulation and delusional misidentification: a four year follow-up study.

We describe a patient, AZ, who showed, in addition to an amnesic syndrome which eventually improved, longstanding confabulation and delusional misidentification following bilateral frontal and right temporal post-traumatic lesions. Confabulation appeared in personal recollections and on long-term verbal memory testing. Misidentification concerned mainly his wife and house. During the four year follow-up AZ's confabulation progressively shrinked so as to become restricted to verbal memory tasks. By contrast, misidentification persisted. General semantic memory was unimpaired throughout, while performance on frontal tests was initially poor and partly improved in time. We argue that confabulation and misidentification, though often intermingled and occurring after similar lesion pattern, should be considered as different neuropsychological entities.

Fatal familial insomnia in a new Italian kindred.

The authors report a new kindred with fatal familial insomnia (FFI)--an inherited prion disease. The propositus had behavioral, sleep, cognitive, and motor impairment associated with thalamic and olivary atrophy. Spongiosis was confined to the parahippocampal gyrus. Protease-resistant prion protein (PrP(res)) was present with widespread distribution. The propositus fits the histopathology of FFI with similar clinical duration and confirms the role of disease duration in determining histopathology and PrP(res) distribution in FFI.

Differential level of platelet amyloid beta precursor protein isoforms: an early marker for Alzheimer disease.

OBJECTIVE: To determine whether a differential level of platelet amyloid beta precursor protein (APP) isoforms is specifically related to Alzheimer disease (AD) and whether it shows a correlation with the progression of clinical symptoms. DESIGN: After subjects were grouped according to diagnosis and severity of dementia, APP isoform levels in platelets were compared. SETTING: University medical centers. PATIENTS: Thirty-two patients who fulfilled diagnostic criteria for probable AD, 25 age-matched control subjects, and 16 patients with non-AD dementia. MAIN OUTCOME MEASURE: The levels of APP isoforms were evaluated by means of Western blot analysis and immunostaining of whole platelets. Messenger RNAs for APP transcripts were also evaluated by means of reverse transcriptase polymerase chain reaction. RESULTS: The ratio between the intensity of the 130-kd and 106- to 110-kd APP isoforms was significantly lower in the AD group (0.31 +/- 0.15, mean +/- SD) compared with both controls (0.84 +/- 0.2) and non-AD subjects (0.97 +/- 0.4). The ratio of platelet APP isoforms in patients with AD grouped by Clinical Diagnostic Rating score significantly correlated with the severity of the disease (Pearson correlation coefficient, followed by Bonferroni correction, P = .01). Reverse transcriptase polymerase chain reaction experiments showed that APP transcripts in all experimental groups were equally expressed. CONCLUSIONS: The pattern of platelet APP isoforms is specifically altered in patients with AD. In addition, the alteration of platelet APP isoforms shows a positive correlation with the progression of clinical symptoms, supporting the possibility to consider this peripheral parameter as a marker of progression of the disease. These alterations are not related to abnormalities of APP isoforms messenger RNAs in platelets.

Intramodal somaesthetic recognition disorders following right and left hemisphere damage.

A dissociation between apperceptive and associative processing after right and left hemisphere damage, respectively, has been suggested for visual, auditory and visuo-tactile matching tasks. This study was aimed at testing for this dissociation in a purely somaesthetic task. Forty consecutive patients with recent right and left hemispheric vascular lesions and 10 normal controls were studied. The groups were compared on two intramodal somaesthetic matching tasks, consisting of either meaningless shapes (apperceptive recognition) or meaningful objects (associative recognition). In normal controls, no significant difference was found either between the two tests, indicating a similar degree of difficulty, or between hands. An analysis of variance indicated a differential impairment of the two hemisphere-damaged groups on the two tests in comparison with normal controls. Right hemisphere lesions impaired the apperceptive, but not the associative, task, while the reverse occurred after left hemisphere lesions. This double dissociation between side of hemispheric lesion (right and left) and level of recognition impairment (apperceptive and associative) extends the results reported for other sensory modalities to intramodal tactile recognition matching.

Interhemispheric communication following unilateral cerebrovascular lesions.

39 patients with a single small cerebrovascular lesion (20 in the right, 19 in the left hemisphere) were subjected to a simple reaction time (RT) task with visual stimuli flashed to the visual field either ipsilateral or contralateral to the cerebral lesion. The subject responded always with the ipsilateral hand. The crossed-uncrossed difference (CUD), i.e. the RT when both stimulus and response occur on the same side minus the RT when stimulus and response occur on opposite sides, is assumed to assess the transit time of information through callosal fibers, and in normal people is about 3-5 msec. In our patients the mean CUD, expressed as the difference between contralateral and ipsilateral responses, was 20 msec. Patients with parietal lesions had still longer CUDs, 37 msec on the average. There was no statistical difference in CUDs between right and left brain-damaged patients. The CUD in brain-damaged patients was of the same order of magnitude as that found in acallosal or split-brain patients. Nonetheless, the present findings are interpreted as reflecting the intrahemispheric rather than the interhemispheric delay in information transmission, with the possible additive effect of an asymmetrical orienting of attention.

Immunological and gadolinium-DTPA MRI evaluation of relapsing remitting multiple sclerosis.

The levels of lymphocytes, blood lymphocytes subsets (CD3+, CD4+, CD8+, DR+, CD25+, CD4+, CD45RA+, CD4+, CD29+ cells) and sIL-2r of 10 patients affected by relapsing-remitting multiple sclerosis were serially studied. The identification of the activity of the disease was made by gadolinium-DTPA (Gd-DTPA) MRI. The immunological determinations and the MRI of the brain and spinal cord were performed every 14th day for a period of three months. No significant difference of the immunological values were found between the presence and the absence of Gd-DTPA enhancing areas, except lymphocytes (p < 0.05). These immunological parameters, evaluated in the peripheral blood, are not a marker of disease activity in relapsing-remitting MS patients.

The neuropsychological consequences of HIV infection in drug addicts.

The occurrence of neuropsychological impairment in asymptomatic, HIV-positive individuals is controversial. In the present study we compared the performance of three groups of chronic intravenous drug abusers (HIV negative, asymptomatic HIV positive, AIDS) on a battery of neuropsychological tests. While the AIDS group was significantly impaired, no difference was found between HIV negative and HIV positive asymptomatic subjects on any measure. This finding is in agreement with the results of studies of homosexual and bisexual subjects, indicating that the presence of HIV infection in the asymptomatic stage does not carry an added risk of cognitive impairment in drug addicts.

Simple reaction time to lateralized visual stimuli is not related to the hemispheric side of lesion.

The effect of a single brain lesion on Reaction Times (RTs) to unpatterned visual stimuli was studied in 20 right brain-damaged (RBD) and 19 left brain-damaged (LBD) patients with single small vascular lesions confined to one hemisphere and free of visual field defects and of significant neuropsychological abnormalities (e.g. aphasia or hemineglect). The stimulus was presented in the field either ipsilateral or contralateral to the brain lesion. The stimulus location was either blocked in each hemifield or randomly alternating between fields. RTs in RBD patients were not statistically different from RTs in LBD patients. Intrahemispheric site of the lesion also was irrelevant for the lengthening in RTs. Responses to blocked presentations were faster than to random presentations. Responses to the hemifield contralateral to the brain lesion were slower than to ipsilateral hemifield, and the difference was unrelated to the absolute values of RTs. It is concluded, in contrast to other reports, but in agreement with the more recent literature, that there is no hemispheric dominance for RTs.

Gadolinium-pentetic acid magnetic resonance imaging in patients with relapsing remitting multiple sclerosis.

Ten patients with relapsing-remitting multiple sclerosis have been studied by serial gadolinium-pentetic acid magnetic resonance imaging (MRI) every 14 days for 3 months. At the end of the follow-up, seven relapses occurred in six patients; no therapy was administered during the study. Ninety-three enhancing lesions were collected in eight patients. With regard to the duration of the enhancement, 32 lesions were detected in only one MRI scan and 32 were found in more MRI scans (most of the lesions occurring in two serial examinations). Four old lesions increased their size with delayed enhancement. Correlation was found between the relapses and the gadolinium-pentetic acid-enhancing areas only for one brain-stem and two cervical spinal cord lesions. Gadolinium-pentetic acid MRI provides useful information about activity of the disease that cannot be obtained clinically even if the dynamic of the lesions may be undervalued in old plaques.