P. Bergonzi

Correlations between individual clinical manifestations and CTG repeat amplification in myotonic dystrophy.

Myotonic dystrophy (DM) is a multisystemic disease caused by the expansion of a CTG repeat, located in the 3′‐untranslated region of the DMPK gene. The number of CTG repeats broadly correlates with the overall severity of the disease. However, correlations between CTG repeat number and presence/absence or severity of individual clinical manifestations in the same patients are yet scarce. In this study the number of CTG repeats detected in blood cells of 24 DM subjects was correlated with the severity of single clinical manifestations. The presence/absence of muscular atrophy, respiratory insufficiency, cardiac abnormalities, diabetes, cataract, sleep disorders, sterility or hypogonadism is not related to the number of CTG repeats. Muscular atrophy and respiratory insufficiency are present with the highest frequency, occurring in 96 and 92% of the cases, respectively. A significant correlation was found with age of onset (r=−0.57, p<0.01), muscular disability (r=0.46, p<0.05), intellective quotient (r=−0.58, p<0.01) and short‐term memory (r=−0.59, p<0.01). Therefore, the CTG repeat number has a predictive value only in the case of some clinical manifestations, this suggesting that pathogenetic mechanisms of DM may differ depending on the tissue.

Sensory gating deficit assessed by P50/Pb middle latency event related potential in Alzheimer's disease.

Summary: Sensory gating is defined as the brain’s ability to inhibit repetitive and irrelevant incoming sensory stimuli and is supposed to be related to cholinergic transmission. Indeed, Alzheimer’s disease (AD) is characterized by a cholinergic deficit that is believed to be involved in cerebral cortex hyperexcitability and short latency afferent inhibition deficit. Therefore, a sensory gating deficit may be supposed present in AD within the frame of cortex hyperexcitability and loss of cortex modulation of sensory inputs. The authors investigated whether a sensory gating deficit may be present in AD and whether this deficit may be related to the presence of neuropsychiatric symptoms (NPS) and reversed by donepezil treatment. Sensory gating was evaluated using a paired-stimulus auditory P50 event-related potential paradigm. Eighteen drug-naïve probable AD patients (mean age 76.1 years; SD 5.6 years; 13 females and 5 males) and 15 healthy elderly controls (mean age 74.2 years; SD 5.4 years; 10 females and 5 males) were recruited. Sensory gating was evaluated in AD patients before starting therapy and after 1 and 3 months of donepezil treatment. Auditory P50 sensory gating was impaired in AD patients but no correlation was found between gating deficit and NPS. Moreover, AD patients displayed increased P50 amplitude when compared with healthy elderly subjects. Donepezil treatment did not improve P50 sensory gating in AD patients but decreased P50 amplitude. Patients with AD displayed an augmented P50 amplitude, in accordance with previous studies, suggesting increased cortex excitability. Donepezil does not affect P50 sensory gating but reduces P50 amplitude. Donepezil may induce P50 amplitude reduction by means of enhanced dopamine release. Indeed, it has been demonstrated that donepezil induces dopamine release “in vitro.” The findings suggest that AD patients have a sensory gating impairment but the link with both NPS and the cholinergic deficit is doubtful.

Relationship between Delta, Sigma, Beta, and Gamma EEG bands at REM sleep onset and REM sleep end.

OBJECTIVE The aim of the present study was to analyze in detail the relationship of two newly introduced measures, related to the Beta and Gamma EEG bands during REM sleep, with Delta and Sigma activity at REM sleep onset and REM sleep end, in order to understand their eventual role in the sleep modulation mechanism. METHODS For this purpose, power spectra of 1 EEG channel (C4, referred to A1) were obtained by means of the fast Fourier transform and the power of the bands ranging 0.75-4.50 Hz (Delta), 4.75-7.75 (Theta), 8.00-12.25 (Alpha), 12.50-15.00 (Sigma), 15.25-24.75 (Beta), 25.00-34.75 (Gamma 1), and 35.00-44.75 (Gamma 2) was calculated for the whole period of analysis (7 h), in 10 healthy subjects. Additionally, two other time series were calculated: the ratio between Beta and Gamma2, and between Gamma1 and Gamma2 (Beta and Gamma ratios). For each subject, we extracted 3 epochs of 30 min corresponding to the 15 min preceding and the 15 min following the onset of the first 3 REM episodes. Data were then averaged in order to obtain group mean values and standard deviation. The same process was applied to the 30-min epochs around REM sleep end. RESULTS The course of the Delta band around REM sleep onset was found to be characterized by a first phase of slow decline lasting from the beginning of our window up to a few seconds before REM onset; this phase was followed by a sudden, short decrease centered around REM onset, lasting for approximately 1.5-2 min. At the end of this phase, the Delta band reached its lowest values and remained stable up to the end of the time window. The Sigma band showed a similar course with stable values before and after REM sleep onset. The Beta and Gamma ratios also showed a 3-phase course; the first phase, in this case, was characterized by stable low values, from the beginning of our window up to approximately 5 min before REM onset. The following second phase was characterized by an increase which reached its maximum shortly after REM sleep onset (approximately 1 min). In the last phase, both Beta and Gamma ratios showed stable high values, up to the end of our time window. At REM sleep end, the Delta band only showed a very small gradual increase, the Sigma band presented a more evident gradual increase; on the contrary, both Beta and Gamma ratios showed a small gradual decrease. CONCLUSIONS The results of the present study show a different time synchronization of the changes in the Delta band and in Beta and Gamma ratios, at around REM sleep onset, and seem to suggest that the oscillations of these parameters might be modulated by mechanisms more complex than a simple reciprocity. All these considerations point to the fact that REM sleep can be considered as a complex phenomenon and the analysis of high-frequency EEG bands and of our Beta and Gamma ratios represent an additional important element to include in the study of this sleep stage.

Headache attributed to intracranial tumours: A prospective cohort study

Between January 2007 and March 2008, we prospectively studied all patients operated on for intracranial tumours in our Department of Neurosurgery. Preoperatively, all patients were interviewed by a neurologist to collect headache characteristics. Measurements of tumour and oedema volume were made using dedicated software for magnetic resonance imaging studies. Tumour histopathology was established by histological examination postoperatively. If headache improved postoperatively, a diagnosis of ‘headache attributed to intracranial neoplasm’ was made, according to the 2004 International Classification of Headache Disorders (ICHD-II). A multivariate logistic regression model was used to evaluate the association of headache with potential risk factors. We studied 206 subjects. The prevalence of tumour headache was 47.6%. Intracranial tumour headache was non-specific and in most cases could not be classified by current ICHD-II diagnostic criteria for primary headache syndromes. Its prevalence varied depending on volume, location and type of tumour, as well as on the patients previous headache history.

Migraine in Adolescents: Validation of a Screening Questionnaire

Background.— Few studies in adolescents deal with the level of agreement between questionnaire and interview information in relation to headache symptoms.

Sclerosteosis: report of a case in a black African man.

Sclerosteosis is a rare genetic disorder of bone modelling, similar to, but distinct from, van Buchem disease; it has been described almost exclusively in Afrikaners of South Africa, a white population of Dutch ancestry. Isolated cases have been reported in a girl in Japan, a boy in Spain, and in multiracial families in Brazil and USA.

Sleep and sleep deprivation as EEG activating methods

OBJECTIVES We examined retrospectively 19 patients with a history of clinical seizures, but normal activity or unclear epileptiform abnormalities in wake EEG recordings and obtained preliminary data for a controlled cohort study to evaluate the effects of sleep deprivation (SD) on interictal epileptic activity. METHODS Nineteen patients referred to our EEG department for diagnostic or follow-up purposes were divided in two groups on the basis of the different EEG protocols applied. The first group (n=5) underwent two laboratory polysomnographies during afternoon naps, after SD, but the patients failed to fall asleep in one of the two occasions. The second group (n=14) was submitted to two polysomnographies, the first without SD and the second after SD. RESULTS The first group of patients demonstrated focal epileptic discharges in 4 patients in which wake after SD appeared to be less activated that sleep after SD. In the second group the results obtained from the waking part of the recordings suggest a lack of activating effect due to SD. CONCLUSIONS SD does not seem to offer greater activation than sleep alone. However, a mild SD may be a convenient activating method for inducing sleep and drowsiness without using any drug.

The accuracy of discharge diagnosis coding for Amyotrophic Lateral Sclerosis in a large teaching hospital

To evaluate the accuracy of hospital discharge data as a source of Amyotrophic Lateral Sclerosis (ALS) cases for epidemiological studies or disease registries, a validation study was performed. All records of patients discharged in 2005 and 2006 with principal or secondary International Classification of Diseases, 9th rev., Clinical Modification (ICD 9 CM) diagnosis code of ALS (335.20), other anterior horn cell disease (335), spinal cord disease (336), hereditary and idiopathic peripheral neuropathy (356), inflammatory and toxic neuropathy (357), myoneural disorders (358), muscular dystrophies and myopathies (359), were selected from the electronic archive of discharge data of the University Hospital of Udine, Friuli Venezia Giulia Region, North East Italy. Corresponding clinical documentation was reviewed to ascertain the presence of El Escorial criteria, the gold standard. Sensitivity of the ICD 9 CM discharge code 335.20 was 93% (95%CI: 82–99%) and decreased to 91% (95%CI: 77–98%) when suspect ALS was excluded. Specificity was 99% (95%CI: 97–99%). The ICD 9 CM discharge code 335.20 can identify a high percentage of hospitalizations of patients truly affected by ALS and of patients with no ALS, among selected neurological diagnostic codes. To ensure complete ALS case ascertainment, prospective population-based registries or epidemiologic studies require active prospective surveillance and use of multiple sources, among them hospital discharge archives can provide accurate information.

Hypnic headache secondary to a growth hormone-secreting pituitary tumour

Hypnic headache (HH) is a rare, benign, chronic headache disorder, usually affecting aged people and characterized by a close relation to sleep. It was first described by Raskin in 1988 (1). Diagnostic criteria for HH have been established, and HH is included in the recent International Headache Society (IHS) classification as a primary form of headache (IHS classification 4.5) (2). At the time of writing, > 100 cases have been reported in the literature (for review see (3)). Furthermore, several patients with this disorder have been described in Italy (4–12). The pathophysiology of HH remains unclear (13). In most instances, even extensive neurological and neuroradiological examinations will be normal (14). However, symptomatic HH has been reported in relation to obstructive sleep apnoea syndrome (15), arterial hypertension (3), pontine stroke (16) and posterior fossa meningioma (17). We report a case of HH in an acromegalic patient with an intrasellar pituitary adenoma.

Hemifacial spasm due to a tentorial paramedian meningioma: a case report

Hemifacial spasm (HFS) is a movement disorder characterised by involuntary paroxysmal facial movements that usually involve the orbicularis oculi and then spread to the other facial muscles. A microvascular compression and demyelination of the seventh nerve at its exit from the brain stem is considered to be the main aetiology of HFS. In addition to rare idiopathic (cryptogenetic) cases, others causes of HFS exist: tumours or vascular malformations have been described, of both the ipsilateral and contralateral cerebellopontine angle (CPA). However, space-occupying lesions in locations other than CPA are usually not thought to be responsible for HFS. Here we describe the case of a 45-year-old woman suffering from HFS, who dramatically improved after surgical removal of a tentorial paramedian meningioma.